3. The Tools – STM and AFM

uk: Математика, природничі науки

description: Nanocar Race Part 3: STM and AFM The Swiss Nanodragster has a size of about 1.5 nm (this is 100 000 times smaller than the diameter of a hair, diameter of a hair 0.15 mm compared to 1.5 nm). To see such a small molecule we need very precise tools. We use a special microscope to see the Nanocar. We use a Scanning Tunneling Microscope (STM) and Atomic Force Microscope (AFM) to image our Nanocar. STM and AFM are scanning probe techniques which means that we scan the sample with a sharp tip, because the resolution of optical microscopes is not good enough to see a single molecule. It is limited by the wavelength of the light. Our tip has the size of an atom. We scan the tip over the sample. If the tip is very close to the surface and a voltage is applied between tip and sample, there will be a small current because of the tunneling effect. In quantum mechanics it is possible for a small amount of electrons to walk through a wall! And we measure exactly these few electrons that pass the wall between the sample and the tip. In that way we don’t need to touch the sample which could for example destroy the molecule. Imagine a mini RC car would be our molecule. The minicar is approximately 10 cm long. Then we could say that we scan with a tip that is as huge as the Matterhorn over the minicar and try to get out an image. The tunneling current is strongly depending on the distance between tip and sample. You can only see it if the tip is very close. We use a a lot of electronics to create a feedback system that keeps the tunneling current constant. In this way we can control the distance between the tip and sample. Then we scan the tip line by line over the molecule. Since the molecule is higher than the surrounding substrate the distance between tip and molecule is lower and the current increases. The feedback system immediately reacts and retract the tip farer away from the molecule to keep the current constant. This movement is recorded by a computer. From this data we get a 3D image of the molecule. The Atomic Force Microscope (AFM) works in a different way. The atomic force is the force that acts between two atoms that come very close. In a simple picture you can think of the force between the first atom of the tip and the closest atom of the molecule. We use this force instead of the tunneling current to control the feedback system of the microscope. With the AFM you can see the chemical structure of the molecule and you can probe different properties of the molecule for example the charge distribution. Here in Basel you can find the first AFM ever built! This year it is the 30. anniversary of the AFM. Christoph Gerber, Professor in Basel, recently won the Kavli Price for the invention of the AFM and Ernst Meyer, our group leader, was the first PhD student who ever worked with an AFM.

uk: вхід без авторизації


Guido Westhoff

type: Person

de: Chemie

fi: kemia

uk: Хімія

en: Chemistry

fr: Chimie

da: Kemi

es: Química

nl: Scheikunde

de: Mathematik, Naturwissenschaften

uk: Математика, природничі науки

en: Mathematics, Natural Sciences

description: The body surface of snakes is one of the most interesting biological surfaces with fascinating functions. Being limbless snakes use their entire body not only for locomotion, but also for catching prey, reproduction, camouflage. This means that the body surface of snakes has to endure constant exposure to frictional forces which usually lead to abrasion. Snakes are masters of adaptation and, in order to survive over 150 Million years in a vast spectrum of ecosystems, have developed a great deal of optimizations for sliding locomotion. In order to grasp how snakes cope with the problem of abrasion and to see if there is a habitat specialization, a comparative analysis of four different snake species specialized to different habitats (Lampropeltis getula californiae (terrestrial), Epicrates cenchria cenchria (all-rounder), Morelia viridis (arboreal), and Gongylophis colubrinus (sand burrowing)) was conducted. Since little was known about abrasion properties of the snake skin, scanning electron microscopy, scratch tests and nanoindentation measurements were conducted to understand abrasion resistance of this biologal material.

TIB AV-Portal

type: Service

type: WebContent

type: MediaObject

@language: en

cs: přihlášení není vyžadováno

de: keine Anmeldung erforderlich

uk: вхід без авторизації

en: no login required

nl: geen login vereist

name: Snake skin as functional biological material – Abrasion properties

name: Beilstein-Institut zur Förderung der Chemischen Wissenschaften

addressCountry: DE

addressLocality: Frankfurt am Main

addressRegion: Hesse

type: Organization

cs: Video

de: Video

fi: Video

uk: Відео

en: Video

fr: Vidéo

da: Video

nl: Video

es: Video


keywords: reactions catalysis

uk: Математика, природничі науки

description: In this video the detailed synthesis of a boron based bidentate Lewis acid is shown step by step. The Lewis acid is used to great success as a catalyst for inverse-electron-demand Diels–Alder (IEDDA) reactions of 1,2-diazines with various dienophiles to access substituted aromatic compounds.

uk: вхід без авторизації

name: Recipe for the preparation of a bidentate Lewis acid catalyst


uk: Математика, природничі науки

description: New concepts in catalysis are without doubt the key for the success of efficient and sustainable synthesis and will be the basis to address today’s challenges of our society, such as energy and shortage of resources. In this video the basic idea of using bidentate Lewis acids in organic synthesis is explained, which has been developed in the group of H. Wegner at the Justus Liebig University in Giessen (Germany). Finally, the methodology is showcased by demonstrating an inverse electron-demand Diels-Alder reaction in the laboratory.

uk: вхід без авторизації

name: Bidentate lewis acid catalysis for organic synthesis


5. Eine Piste aus Gold

keywords:
microscopy
molecular dynamics

uk: Математика, природничі науки

description: Wie “baut” man die Rennstrecke? Und vor allem: Wie setzt man die Moleküle für das Rennen auf den Chip? Tobias spricht von einer grossen technischen Herausforderung (3:29 min) beim Auftragen aller Nanocars auf die Rennstrecke. Bei normalen Messungen werden immer nur Moleküle einer Art auf die Probe aufgedampft. Beim Nanocar Race jedoch sollen 4 verschiedene Moleküle mit 4 unterschiedlichen Verdampfungstemperaturen auf ein und dieselbe Probe gebracht werden. Dabei kann eine zu hohe Verdampfungstemperatur von Molekül 1 bewirken, dass das Molekül 2 im Verdampfer ebenfalls verdampft und auf die Rennstrecke fliegt. Außerdem müssen manche Nanocars nach dem Auftragen erst noch aktiviert werden, in dem die Probe erhitzt wird. Andere Nanocars auf der Probe würde das beschädigen oder eventuell zerstören. Deshalb müssen die Nanocars einzeln nacheinander aufgetragen werden. Dazu muss eine optimale Reihenfolge unter den gegebenen Rahmenbedingungen gefunden werden. Eine weitere Herausforderung dabei ist, die 4 Nanocars räumlich voneinander auf der Probe zu trennen. Jedes Team bekommt ein Viertel der Probe und jeweils eine der 4 Spitzen. Um jeweils nur ein Nanocar auf dem jeweiligen Viertel zu haben, müssen die anderen Dreiviertel der Probe beim Auftragen abgedeckt werden. Das geschieht mit speziell für das Rennen angefertigten Masken, die nacheinander über der Probe aufgesteckt werden.”

@language: de

uk: вхід без авторизації


4. Wie steuert man ein Nanocar?

uk: Математика, природничі науки

description: Im Frühjahr 2017 findet in Toulouse (Frankreich) das kleinste Autorennen der Welt statt. Molekülgroße Fahrzeuge gehen dort an den Start. Auf einer Rennstrecke, die gerade mal einen Zehntausendstelmillimeter lang ist, konkurrieren sechs Forscherteams aus den USA, Japan, Deutschland, Frankreich Österreich und der Schweiz um den Sieg. Wie aber kann man ein einzelnes Molekül bewegen und dabei auch noch steuern? Das ist gar nicht so einfach, wie Niklas von Tobias erfährt.

uk: вхід без авторизації


3. Wie man ein Nanocar sehen kann

uk: Математика, природничі науки

description: Nanocar Race Teil 3: Moleküle kann man nicht mit einem einfachen Mikroskop betrachten. Tobias benutzt dazu ein Scanning Tunneling Microscope (STM, englisch für Rastertunnelmikroskop). Wie funktioniert das? Das STM wurde 1981 im Schweizer Rüschlikon entwickelt. Die beiden Physiker Gerd Binnig (Deutschland) und Heinrich Rohrer (Schweiz), erhielten hierfür 1986 den Nobelpreis für Physik. Auch der Baseler Forscher Christoph Gerber war an der Entwicklung des STM beteiligt. Gemeinsam mit Calvin Quate und Gerd Binnig wurde ihm 2016 einer der drei Kavli-Preise zugesprochen.

uk: вхід без авторизації


2. Der Swiss Nano Dragster

uk: Математика, природничі науки

description: Nanocar Race Teil 2: Im Frühjahr 2017 findet in Toulouse (Frankreich) ein Rennen der kleinsten Autos der Welt statt. Molekülgroße Fahrzeuge gehen dort an den Start. Auf einer Rennstrecke, die gerade mal einen Zehntausendstelmillimeter lang ist, konkurrieren sechs Forscherteams aus den USA, Japan, Deutschland, Frankreich, Österreich und der Schweiz um den Sieg. Tobias zeigt, wie der Baseler “Nano Dragster” aufgebaut ist und erklärt den “Motor” und den Spoiler des Renn-Moleküls. Das Rennen fand inzwischen am 28.4.2017 statt und Tobias und sein Team gewannen tatsächlich das Rennen auf einer Goldoberfläche. Mehr dazu auf dem Youtube-Kanal des Nanocar Race. (In englisch) Übrigens: Der Nobelpreis für Chemie 2016 geht an die Molekülforscher Jean-Pierre Sauvage, Sir James Fraser Stoddart und Bernard L. Feringa. Sie werden für die Entwicklung molekularer Maschinen geehrt, die für neue Materialien, Sensoren und Energiespeicher verwendet werden könnten. Das zeigt, wie wichtig die Forschung an “molekularen Maschinen” inzwischen geworden ist.

uk: вхід без авторизації


1. Die kleinsten Autos der Welt

uk: Математика, природничі науки

description: Nanocar Race Teil 1: Im Frühjahr 2017 findet in Toulouse (Frankreich) ein Rennen der kleinsten Autos der Welt statt. Molekülgroße Fahrzeuge gehen dort an den Start. Auf einer Rennstrecke, die gerade mal einen Zehntausendstelmillimeter lang ist, konkurrieren sechs Forscherteams aus den USA, Japan, Deutschland, Frankreich, Österreich und der Schweiz um den Sieg. Niklas hat für Beilstein TV eines der Teams besucht und ist dafür nach Basel gefahren. Tobias Meier ist Doktorand an der Universität Basel und steuert als Co-Pilot das Schweizer Molekular-Auto. Es geht darum, einzelne Moleküle möglichst schnell über eine Rennstrecke von etwa 100 Nanometern zu bewegen. Wie dese Moleküle aussehen, wie man sie überhaupt sieht und steuert, wie die Rennstrecke beschaffen sein muss und welche Umweltbedingungen herrschen müssen, das zeigen wir Euch in unseren Videos. Übrigens: Für die beteiligten Forscherteams ist das NanoCar Race nicht nur Spaß, sondern ernsthafte Grundlagenforschung: Vielleicht kann man mit den dabei gewonnenen Erkenntnissen eines Tages in der Nanoelektronik Computerchips oder Solarzellen bauen, vielleicht auch funktionale Oberflächen, die sich selbstständig organisieren. Doch das ist Zukunftsmusik. Immerhin: Der Nobelpreis für Chemie 2016 ging an an drei Nanowissenschaftler, die gezeigt haben, wie man Propeller, Getriebe und sogar Nanoautos aus organischen Molekülen herstellen kann.

uk: вхід без авторизації


Können Metall-Ionen heilen helfen?

uk: Математика, природничі науки

description: Dass Eisen in den roten Blutkörperchen für den Sauerstofftransport unerlässlich ist, zeigt, dass Metalle eine wichtige Rolle für den menschlichen Körper spielen. Doch kann man mit Metallverbindungen vielleicht auch Krebs heilen? Der Bochumer Wissenschaftler Nils Metzler-Nolte versucht mit seinem Team, genau das herauszufinden.

uk: вхід без авторизації


Vom Tensid zur Biomembran

uk: Математика, природничі науки

description: Kann man im Labor Biomembranen künstlich herstellen? Das Video zeigt, wie ein Göttinger Forscherteam daran arbeitet. Im Sonderforschungsbereich (SFB 803) werden fakultätsübergreifend die Grundlagen der Organisation und Funktion von Proteinen und Peptiden in Lipidmembranen sowie die molekularen Strukturen der Membran-Membran-Interaktion an artifiziellen Membransystemen erforscht. Damit wird eine Basis für das Verständnis von medizinischen Fragestellungen beispielsweise zum Transport von Substanzen in Zellen (Zelllogistik) geschaffen. Ziel im Rahmen dieses Projektes ist es, Schülerinnen und Schüler an dieser hochaktuellen, interdisziplinären Forschung teilhaben zu lassen und damit eine Brücke zwischen Schule und Universität zu schaffen. Aktuell wird beispielsweise ein Unterrichtsbeispiel “Vom Tensid zur Membran” entwickelt, welches an das im Chemie- und Biologieunterricht vermittelte Basiswissen anknüpft und diese durch Bezüge zu aktuellen Forschungsfragen für Naturwissenschaften begeistern soll. Hierbei sollen Schülerinnen und Schüler basierend auf Kenntnissen zum Molekülbau und Polaritäten sowie der Selbstorganisation von Tensiden zu einem Verständnis vom Aufbau und der Organisation von Biomembranen gelangen. Die Bedeutung von Biomembranen als Barriere zur Abgrenzung von Reaktionsräumen wird durch Experimente vertieft. Zudem werden einzelne Forschungsthemen anhand anschaulicher Modelle und Videos dargestellt und soweit reduziert, dass die Lernenden die zuvor vermittelten Grundlagen darin wiederfinden.

uk: вхід без авторизації


Der kleinste Schalter der Welt

uk: Математика, природничі науки

description: Wie funktionieren sogenannte molekulare Lichtschalter? Ein molekularer Lichtschalter ist ein Molekül, das sich durch die gezielte Bestrahlung mit Licht in einen von zwei Zuständen versetzen lässt. Aber wie geht das bei einem winzigen Molekül? Das hat sich Niklas von Stefan Hecht von der Humbold Universität Berlin erklären lassen. Wie funktioniert ein molekularer Lichtschalter? Ein solcher Lichtschalter ist nichts anderes als ein Molekül, das sich durch die gezielte Bestrahlung mit Licht in einen von zwei Zuständen versetzen lässt, so wie normale Lichtschalter bei uns zuhause – entweder der Schalter ist an oder aus. Dementsprechend braucht man für einen molekularen Lichtschalter ein Molekül, das in zwei Formen existieren kann, Chemiker sagen dazu Isomere. Aber um das Ganze nicht komplizierter zu machen, als es ist, nehmen wir hier zur Erklärung diese beiden kleinen Männchen. Eines der beiden Männchen, das rechte, hat etwas mehr Energie als das andere und kann deshalb nicht nur einen sondern beide Arme hochhalten. Denn es geht hier um verschiedene Energiezustände – das wird später noch wichtig werden. Der Berg in der Mitte trennt beide Energiezustände von einander. Bei Normaltemperatur hat der kleine Kerl auf der linken Seite nicht genug Energie, um den Berg hinaufzuklettern. Und da kommt das Licht ins Spiel. Wir können ihn mit Licht bestrahlen, zum Beispiel blauem Licht, und er wird wie mit einem Aufzug auf eine höhere Ebene transportiert. Das ist der sogenannte angeregte Zustand und Moleküle können ihn nur erreichen, wenn sie ein Photon absorbieren, die kleinste Einheit an Lichtenergie. Da Moleküle ebenso wie Menschen üblicherweise gerne ausruhen, möchte der Kerl gerne seine überschüssige Energie loswerden. Also verlässt er seinen angeregten Zustand und fällt zunächst in ein Tal, das direkt auf den Berg führt, der die zwei Täler im Grundzustand teilt. An diesem Punkt, dem Durchlass des sogenannten photochemischen Trichters, fällt er hindurch auf die rechte Seite. Die Lichtenergie hat ihn aber verändert – jetzt kann er auch den anderen Arm heben. Nun kann das Kerlchen auf der rechten Seite aber ebenfalls nicht den Berg hinaufklettern, vor allem nicht bei normalen Temperaturen. Da er jedoch weniger stabil ist, immerhin hat er jetzt mehr Energie als zuvor, reicht jetzt Licht mit weniger Energie, zum Beispiel grünes Licht, um ihn wieder in den angeregten Zustand zu versetzen und ihn dann durch den Trichter auf die linke Seite fallen zu lassen. Wir haben also zwei verschiedene Kerlchen – oder sagen wir jetzt besser wieder Moleküle – die ineinander umgewandelt werden können, indem man sie mit Licht unterschiedlicher Farbe bzw. Energie bestrahlt. So können wir jedes der beiden verschiedenen Isomere gezielt ansprechen und in das andere umwandeln. Wir haben also einen molekularen Schalter. Das Geniale dabei ist: beide Schaltstufen haben unterschiedliche Eigenschaften, die wir nutzen können. Noch einmal zurück zur Analogie. Während der Kerl auf der Linken seine Hände weit von einander entfernt hält, hat der auf der Rechten sie beisammen und kann damit etwas tun. In anderen Worten: Der linke Kerl ruht sich gerade aus und tut nichts. Der rechte Kerl ist aktiv und kann verschiedene Dinge tun – zum Beispiel Klavierspielen. Wenn wir das richtige Licht benutzen, können wir zwischen den beiden Männchen hin- und herschalten und so die Musik an oder aus machen. Das ist – in aller Kürze – das Konzept eines ferngesteuerten molekularen Schalters mit Hilfe von Licht.

uk: вхід без авторизації


Krebstherapie mit Schwerionen

de: Physik, Astronomie

fi: fysiikka, tähtitiede

uk: Фізика, Астрономія

en: Physics, Astronomy

fr: Physique, Astronomie

da: Fysik, Astronomi

es: Física, Astronomía

nl: Natuurkunde, Astronomie

uk: Математика, природничі науки

description: Schwerionenforschung Teil 6: Der Physiker Robert Kaderka zeigt uns, wie man mit Schwerionen aus einem Beschleuniger Hirntumore zerstören kann. Das können bisher nur wenige Zentren weltweit. Kaderka arbeitet nun daran, das Verfahren auf mehr Krebsarten auszudehnen.

uk: вхід без авторизації


Warum sind wir so schwer wie wir sind?

uk: Фізика, Астрономія

uk: Математика, природничі науки

description: Schwerionenforschung Teil 5: Objekte in der Natur sind schwerer als sie eigentlich sein sollten. Wie bekommt zum Beispiel ein Proton seine Masse? Die Professorin Concettina Sfienti versucht das herauszufinden. Mit Hilfe von Antimaterie und eines Schwerionen-Beschleunigers an der GSI in Darmstadt

uk: вхід без авторизації


uk: Фізика, Астрономія

uk: Математика, природничі науки

description: Schwerionenforschung Teil 4: In den sogenannten Neutronensternen vermutet die Wissenschaft eine exotische Suppe aus Atombausteinen: Ein Quark-Gluon-Plasma. Um dieses Phänomen zu verstehen, schafft die Physikerin Tetyana Galatyuk, bei GSI im Labor Bedingungen wie in einem Neutronenstern.

uk: вхід без авторизації

name: Von der Supernova bis zum Neutronenstern


Der Sternenstaub aus der Supernova

uk: Фізика, Астрономія

uk: Математика, природничі науки

description: Schwerionenforschung Teil 3: Das Leben auf unserer Erde basiert auf rund 90 Elementen. Fast alle Elemente sind einmal im Inneren von Sternen und bei Sternexplosionen, sogenannten Supernovae entstanden. Was dabei in Sternen auf atomarer Ebene geschieht, will der Physiker Karlheinz Langanke in Damstadt herausfinden.

uk: вхід без авторизації


Wie entdeckt man neue Elemente?

uk: Фізика, Астрономія

uk: Математика, природничі науки

description: Schwerionenforschung Teil 2: Wie entdeckt man neue Elemente? Der Physiker Sigurd Hofmann zeigt, wie man mit einem Beschleuniger neue chemische Elemente finden kann, die es so vielleicht nur im Labor geben kann. Inzwischen wurden weltweit Elemente bis zur Ordnungszahl 118 entdeckt.

uk: вхід без авторизації


uk: Фізика, Астрономія

uk: Математика, природничі науки

description: Schwerionenforschung Teil 1: Der Physiker Jens Stadlmann entwickelt Beschleuniger bei GSI, dem Helmholtzzentrum für Schwerionenforschung in Darmstadt. Hier steht ein Teilchenbeschleuniger mit ganz besonderen Fähigkeiten.

uk: вхід без авторизації

name: Wie funktioniert ein Teilchenbeschleuniger?


keywords: catalysis polymers

uk: Математика, природничі науки

description: At the beginning of this video we will show you two different batch methods for the formation of vesicles and their limitations which were adapted from the liposome preparation techniques. Compared to this, the next presentation of a continuous process for the production and in-situ loading of polymersomes illustrates the outstanding advantages of micro technology for nano engineering. Polymersomes are the synthetic analogues to liposomes and a relatively new kind of soft nanoparticles, which have already shown great promise as drug carriers. They are composed of amphiphilic block copolymers instead of phospholipids like their natural counterparts. Due to the good synthetic control of polymer chemistry, polymersomes provide much more variability, stability and functionality than liposomes. The formation of polymersomes by controlled self-assembly can be induced by transferring the block copolymer in a selective solvent, for example water. In this case hydrophobic parts will associate in order to prevent the unfavorable contact with water, while the hydrophilic blocks will face the inner and outer solution. Due to this association, polymersomes have the capability to load hydrophilic molecules as well as hydrophobic ones, which offers advantages over spherical polymer micelles. Nevertheless, the preparation and loading of polymer nanostructures is a challenging task since it must be a highly controllable and continuous process.

uk: вхід без авторизації

name: Continuously manufactured polymersomes by self-assembly using micro-technology


Detecting magnetism on the atomic scale

uk: Математика, природничі науки

description: This video illustrates an experimental study of the electrical transport behaviour of atomic-size contacts and mono-atomic chains of the nonmagnetic metal platinum. The development of atomic-scale structures revealing novel transport phenomena is a major goal of nanotechnology. Examples include chains of atoms that form while stretching a transition metal contact and the formation of magnetic order in these chains, the existence of which is still under debate. Here we illustrate an experimental study of the electrical transport behaviour of atomic-size contacts and mono-atomic chains of the nonmagnetic metal platinum. We find a pronounced and diverse magneto-conductance behaviour that sensitively reacts to tiny changes of the atomic configuration. Technically this is done by stretching a free standing nanobridge of platinum with subatomic precision. These findings can be interpreted as a signature of local magnetic order in the chain, which may be of particular importance for the application of atomic-sized contacts in spintronic devices of the smallest possible size.

uk: вхід без авторизації


keywords: reactions cyclodextrins

uk: Математика, природничі науки

description: Polyrotaxanes are molecular entities in which many rings are threaded onto a polymer chain with attached stopper groups hindering the rings from dissociation. Polyrotaxanes were synthesized from isoprene, styrene and cyclodextrins through a one pot reaction in water similar to an emulsion polymerization. The product can be isolated simply by heat filtration. Slide-ring gels are obtained by cross-linking of the threaded cyclodextrins using diisocyanates.

uk: вхід без авторизації

name: One pot synthesis of a cyclodextrin polyrotaxane and formation of a slide-ring gel


Direct laser interference patterning

uk: Математика, природничі науки

description: This video shows how a pulsed nanosecond laser beam can be used for the modification of a surface with structures on the micron scale in a single shot on an area of mm2. As a start interference is explained with examples of water waves and light. For the light a laser beam is split into two beams which are recombined on the surface to be patterned. The structures are detected by diffraction from the formed surface pattern. Atomic force microscopy is used to image the surface. This technique can be used for the structuring of single molecule layers, catalysts, surfaces of metals, semiconductors and polymers.

uk: вхід без авторизації


Superconducting spin-electronics

uk: Математика, природничі науки

description: Superconductivity and Ferromagnetism were long thought to be opposing states of matter, which are mutually incompatible. Latest research suggests, however, that superconductivity and ferromagnetism can coexist under certain conditions. This creates the foundations of fundamentally new classes of superconducting spin-electronic devices, which are based on the generation and manipulation of spin-carrying supercurrents. In this video we will introduce the concept of superconducting spin-electronics and illustrate two different strategies to create non-dissipative supercurrents in superconductor-ferromagnet hybrid nanostructures.

uk: вхід без авторизації


uk: Математика, природничі науки

description: Many nanooptical applications require suitable nanofabrication technology. Hole-mask colloidal nanolithography has proven to be a low-cost and large-area alternative for the fabrication of complex plasmonic nanostructures as well as metamaterials.

uk: вхід без авторизації

name: Fabrication of low-cost and large-area complex nanostructures: An overview to the concept


Photoswitchable monolayers on silicon

uk: Математика, природничі науки

description: Silicon is one of the most relevant materials for nanotechnology and semiconductor devices. We are presenting the design of naphthopyrans and fulgimides for surface applications and ATR-FTIR studies on silicon(111). The video includes the formation of photoswitchable alkyl monolayers with fulgimide headgroups on silicon(111).

uk: вхід без авторизації


Functional Polymers

keywords: supramolecules polymers

uk: Математика, природничі науки

description: This video deals with the synthesis of functional or “smart”polymers. These interesting polymers respond to an external stimulus by changing their properties reversibly. Such stimuli can be for example light or mechanical force. Such polymers can be used for interesting applications, which are investigated within the Collaborative Research Center 677, which is called “Function by switching”, at Kiel University

uk: вхід без авторизації


keywords: materials polymers

uk: Математика, природничі науки

description: To prevent accidents and damage, detection of materials failure ahead of of the breakdown of a construction is necessary. Especially the material failure in composites like particle or fiber reinforced polymers is a complex process. One solution is to fill the polymer matrix with a material which indicates the mechanical states of the polymer. E.g., a molecular switch which changes its color by different external stimuli like mechanical stress or softening due to temperature. For demonstration a polymer matrix that has shape memory abilities is filled with a very low filling factor of spiropyrane molecules. The colour change of the molecules indicate a the mechanical transformation of the polymer at elevated temperatures. In addition, ZnO microparticles can also be used for failure reporting due to its photoluminescence of surface defects that occur either at higher temperatures or under mechanical damage. In this video scientists from the functional nanomaterials group at the materials science institute of Kiel University will give a demonstration of the unique properties of all the three components mentioned.

uk: вхід без авторизації

name: Nanoscale switches for memorizing polymers


keywords:
photo
molecular dynamics

uk: Математика, природничі науки

description: Photochemically driven molecular switches may serve as motor units in future nanoscale machines. To design such motor units, we need to understand and improve the photochemical dynamics of molecular switches. In CRC 677, scientists from physical, organic and theoretical chemistry are working together towards this aim. In one of these research lines, the well-known molecular switch azobenzene could be improved significantly, by joining the two phenyl rings with an additional ethylenic bridge. With advanced methods of physical and theoretical chemistry, working hand in hand, it was possible to analyze the molecular movements on the femtosecond time scale and to fully understand the reasons for the improved photophysical properties of bridged azobenzene. In ongoing work, further improvements have already been achieved and embeddings of these new photochemical switches into complex molecular environments are studied.

uk: вхід без авторизації

name: Ultrafast molecular switches caught in the act


uk: Математика, природничі науки

description: Computational methods in chemistry speed up the discovery of bioactive compounds and make lab work cheaper and more effective. This starts with the automated mining and analyses of public data and boils down to molecular interaction modelling. Here we concentrate on the latter part exemplified by the development plant PARP-enzyme inhibitors as potential agrochemicals that enhance the survival and yield of crops under drought stress (cf. climate change). The same works for human drugs (e.g. human PARP is an anticancer target). Following the initial generation of a three-dimensional model of a protein target, millions of structures in different conformations are docked and filtered for interaction quality, availability and other properties in a virtual screening procedure. A resulting set of actual compounds is then evaluated in a new bioassay that does not require spraying of plants. It is the first test for drought stress tolerance that uses sterile plant clones in microtiter plates, is fully quantifiable, and concentration dependent. Sources: Tennstedt, S., Fischer, J. Brandt, W., Wessjohann, L. in: Virtual screening – tools for a faster selection of new drug leads”. Medicinal Chemistry in Drug Discovery – Review Book, 2013: 219-236 (Ed. Dubravko Jelić), Transworld Research Network (37/661 (2), Fort P.O., Trivandrum-695 023, Kerala, India), ISBN: 978-81-7895-560-5

uk: вхід без авторизації

name: Computational chemistry aids the discovery of phytoeffectors: (here: plant protectant against drought stress)


Switchable antifreeze proteins

keywords:
photo
natural products

uk: Математика, природничі науки

description: Within project C11 of the SFB 677 researchers at the Otto-Diels- Institute of Organic Chemistry at the Christian-Albrechts-University, Kiel, aim to modify a naturally occurring antifreeze protein from the fish winter flounder to be able to switch its activity off and on by light. The video describes the background of this proteins, its mechanism of action, and the steps needed to modify it and make its activity light sensitive.

uk: вхід без авторизації


uk: Математика, природничі науки

description: Functionalization of surfaces with spin crossover complexes is an intensively studied topic. Starting from dinuclear iron(III)-salten complexes [Fe(salten)-(pyS)]2(BPh4)2 and [Fe(thiotolylsalten)(NCS)]2 with disulfide-containing bridging ligands, the corresponding mononuclear complexes [Fe(salten)(pyS)]+ and [Fe(thiotolylsalten)-(NCS)] were covalently attached to Au(111) surfaces and analyzed with Infrared reflection absorption spectroscopy (IRRAS). In comparison with the bulk material data of the [Fe(salten)pyS]+ complexes , the surface vibrational spectra show an anomaly regarding the geometry of adsorbed complexes. The salten-ligand is partially decoordinated from the Fe(III)center and one of its phenolate arms binds to the Au(111) surface. To find a system, which retains the geometry on the surface, [Fe(thiotolylsalten)NCS] monolayers were prepared and also investigated on the surface. Here no anomaly was observed, which indicates that the coordination sphere of the complex in the bulk is retained on the surface. The implications of these results with respect to the preparation of surface-adsorbed monolayers of functional transition-metal complexes are discussed.

uk: вхід без авторизації

name: Fixation of spin crossover complexes on surfaces


keywords: photo biochemistry

uk: Математика, природничі науки

description: The goal of this project is the development and biological characterization of photoswitchable kinase inhibitors which will be useful for innovative therapeutic approaches with focus on anti-cancer applications.

uk: вхід без авторизації

name: Photoswitchable protein kinase Inhibitors for novel anti-cancer applications


2. Meet the Swiss Nano Dragster

uk: Математика, природничі науки

description: The Swiss Nanodragster is an organic molecule. In our group in Basel, one of our research focuses is the investigation of organic molecules on different surfaces. Organic molecules consist mainly of Carbon atoms and build the basis of all living beings on earth. Molecules that we use are central building blocks in the most important processes in nature like photosynthesis and oxygen transport in blood. An important property of these molecules is to form coordination complexes with metal atoms. It is also possible to build organic solar cells out of this kind of molecules. For our nanocar we use this molecule because it has many advantages. Because of the before mentioned metal coordination there is one defined point where the molecule couples to the surface. This can be used as an engine of the nanocar. Furthermore the molecule is small and prefers to stay isolated on the surface. This is essential for using it as a nanocar. Many molecules build self assemblies which prevents using them as a nanocar. Furthermore the Nanodragster has a CH3 group at the top of the molecule which acts as a spoiler and reduces friction with the surface. In total these properties make the Swiss Nanodragster a very fast nanocar!

uk: вхід без авторизації


1. The Smallest Car in the World

uk: Математика, природничі науки

description: The “Nanocar Race” is an event in which molecular machines compete on a nano-sized racetrack. These “Nanocars” or molecule-cars can have real wheels, an actual chassis…and are propelled by the energy of electric pulses! Nothing is visible to the naked eye, however a unique microscope located in Toulouse will make it possible to follow the race. A genuine scientific prowess and international human adventure, the race is a one-off event, and will be broadcast live on the web in spring 2017.

uk: вхід без авторизації


6. Eine extreme Umwelt

uk: Математика, природничі науки

description: Im Frühjahr 2017 findet in Toulouse (Frankreich) das kleinste Autorennen der Welt statt. Molekülgroße Fahrzeuge gehen dort an den Start. Auf einer Rennstrecke, die gerade mal einen Zehntausendstelmillimeter lang ist, konkurrieren sechs Forscherteams aus den USA, Japan, Deutschland, Frankreich Österreich und der Schweiz um den Sieg. Niklas hat für Beilstein TV eines der Teams besucht und ist dafür nach Basel gefahren. Hier läßt er sich von Tobias Meier erklären, welche äußeren Bedingungen für ein solches Molekülrennen herrschen müssen. Das Rennen fand am 28.4.2017 statt und Tobias und sein Team gewannen tatsächlich das Rennen auf einer Goldoberfläche.

uk: вхід без авторизації


keywords: biochemistry methods

uk: Математика, природничі науки

description: Electrochemistry (EC) coupled to mass spectrometry (MS) in the last years has been proven to serve as a promising tool in the field of metabolism research. In conventional animal based metabolism studies, the identification of especially short living, reactive intermediates is difficult due to their binding to cell components such as proteins. With EC/MS as a purely instrumental approach, most oxidative metabolism reactions can be simulated. This way, it is possible to study the phase I metabolism of xenobiotics including the identification of reactive intermediates. By extending the setup and adding a solution of a biomolecule like a peptide, protein or DNA immediately after EC oxidation, the phase II metabolism can be studied and toxicity assessment can be performed as well.

uk: вхід без авторизації

name: Investigating drug metabolism with electrochemistry / mass spectrometry


Chemical imaging of biological tissues

uk: Математика, природничі науки

description: Chemical imaging has emerged as an important field of research in recent years, and the respective methods are used for the spatially resolved analysis of the elemental and molecular composition of biological or pharmaceutical samples. Here, three different techniques for elemental and molecular imaging including µXRF, LA-ICP-MS and LA-APCI-MS are presented with their major principles and applications.

uk: вхід без авторизації


uk: Математика, природничі науки

description: An elemental species is defined as a particular binding form or oxidation state of the element. The toxicity of a chemical element like Hg, Se or As is not dependent on the total elemental concentration, but rather on the concentration of its respective toxic species. In order to access species information with high sensitivity and selectivity, hyphenated techniques with chromatographic separation and mass spectrometric detection are applied. The concept of speciation analysis is presented for the example of gadolinium-based contrast agents for magnetic resonance imaging, which are discharged in the aquatic environment via the wastewater. In this case, hydrophilic interaction liquid chromatography (HILIC) is combined with electrospray mass spectrometry (ESI-MS) for species identification and inductively

uk: вхід без авторизації

name: Investigation of the anthropogenic Gadolinium (Gd) anomaly: Specification Analysis of Gd-based MRI contrast agents


keywords: catalysis reactions

uk: Математика, природничі науки

description: The video shows the setup and analysis of a chemoenzymatic reaction with the AmbDH3 domain on the semipreparative scale. The synthesis of the enzyme precursor as well as a typical procedure for the production of the catalyst are described. The last two decades have seen a tremendous progress in the understanding of secondary metabolite biosynthesis on the genetic, the enzymatic as well as on the structural level. Such biosynthetic pathways contain a plethora of enzymes that have the potential to become useful biocatalysts. In accordance with their natural role, they would be particularly attractive for an application in natural product synthesis. The ambruticins are a group of polyketide natural products with attractive antifungal activity profile and a low toxicity in mammal. Their biosynthesis contains a couple of enzymes that act via unprecedented mechanisms and which are attractive for an application in the chemoenzymatic synthesis of natural products. The unusual cyclase domain AmbDH3 performs an oxa-Michael addition leading to the formation of one of the tetrahydropyran rings of the ambruticins. As this structural motif is present in many natural products, we are evaluating the potential of this domain to be used as a flexible biocatalytic tool for preparative scale application. The video shows the setup and analysis of a chemoenzymatic reaction with the AmbDH3 domain on the semipreparative scale. The synthesis of the enzyme precursor as well as a typical procedure for the production of the catalyst are described.

uk: вхід без авторизації

name: Chemoenzymatic synthesis of oxygen heterocycles


keywords: materials biomimetics

uk: Математика, природничі науки

description: The ubiquitous human pathogenic Acanthamoeba castellanii can cause severe brain or eye infections like Acanthamoeba keratitis (A. keratitis), which occurs mainly due to wrong contact lens use and can lead to complete vision loss. For immune suppressive individuals it can even cause a granulomatous amoebic encephalitis (GAE). Therefore, research on soft polymers comparable to contact lenses are carried out to investigate the pathogenicity of these amoebae and to develop strategies for avoiding infections with these parasites.

uk: вхід без авторизації

name: Adhesion experiments and analysis of the human pathogen Acanthamoeba castellanii


keywords: materials photo

uk: Математика, природничі науки

description: In this video the interaction of femtosecond laser pulses with metallic nanostructures is demonstrated.These light pulses can excite collective electron oscillations within the nanostructure, so called plasmons. By precisely tailoring the nanostructures, light can, e.g., be coupled into plasmonic waveguides and then squeezed into nanometer-sized volumes, much smaller than the diffraction limit of propagating light. Herewith both the spectroscopic investigation and the ultrafast manipulation of single, nanometer-sized objects are possible. This manipulation is demonstrated in the second part, in which ultrashort light pulses are used to control the propagation of a second light pulse. This plasmonic switch can in principle be orders of magnitude faster than electronic switches.

uk: вхід без авторизації

name: Light-metal interaction on the nanoscale

name: Beilstein-Institut zur Förderung der Chemischen Wissenschaften


uk: Математика, природничі науки

description: In this video we show applications of ultrashort laser pulses. One is to probe the initial steps of charge transfer in a reference organic solar cell material that happen on a femtosecond timescale. We monitor the coherent motion of the polymer and fullerene molecules, which act in our sample as an electron donor and acceptor, by the use of high time-resolution pump-probe spectroscopy. Another application is photoemission of electrons from metallic nanotips illuminated by femtosecond laser pulses. Electron emission is localized to the nanometer-sized apex and may be remotely triggered via adiabatic nanofocussing. Therefore, metallic nanotips provide an ultrafast, nano-localized electron source for application in time-resolved electron microscopy.

uk: вхід без авторизації

name: Femtosecond dynamics of electronic motion in nanostructures


uk: Математика, природничі науки

description: Skin surface on the ventral surface of snakes is optimized for legless locomotion in the course of evolution. This frictional system was investigated using microtribological technique to gain a deepened insight in the specialized surface modifications of the snake skin. In our studies, we have shown that the frictional properties of snake skin are highly optimized to generate frictional anisotropy and to reduce the occurrence of stick-slip motion during sliding. Despite this a strong influence of the effective elastic modulus of underlying layers on the frictional properties in general and the anisotropic frictional properties in particular was shown. We assumed, that snakes are able to alter frictional properties of their ventral body surface by the variation of body stiffness and thereby their effective elastic modulus. These results show that the snake skin is a very attractive biological model for optimizing technical surfaces under tribological stress.

uk: вхід без авторизації

name: Anisotropic frictional properties of snake skin


uk: Математика, природничі науки

description: The principle of contact splitting is mainly used to explain the impressive capabilities of geckos, spiders and some insects to adhere to and to run on walls and ceilings. Those animals have instead of a large continuous contact hundreds to billions of tiny hairs called setae under their feet. Those micro- and nano-structured setae can form intimate contact with the substrate. Based on these findings, many attempts to mimic such adhesive systems were made and a new class of adhesives has emerged: bio-inspired microstructured adhesives. Although some convincing examples have shown their usefulness in some real life applications, a reliable alternative to conventional bonding strategies is still lacking. However, our recent works on the hairy adhesive systems in insects have revealed two important features within individual setae which allow for robust and reliable reversible adhesion: (1) the presence of a material gradient along the setae leads to an enhanced adaptability to rough surfaces and prevents clusterization of setae and (2) the presence of joint-like elements within setae further enhances the adaptability and allows for robust adhesion.

uk: вхід без авторизації

name: Functional gradients in fibrillar adhesives


uk: Математика, природничі науки

description: Homoeriodictyol (HED) is a flavan type natural product active as bitter blocker. It was used as a lead compound to identify further natural products with a similar activity in silico and by sensory evaluation. In addition to conventional chemical synthesis, there is a demand for biotechnological production means of food additives. Therefore, enzyme cascades able to convert available natural precursors to high value products have been identified. Enzymes are rationally re-designed in silico for better performance, and then combined in vitro and in vivo for the one pot production of the target compound. Research in the Wessjohann group combines several disciplines like natural product discovery, analysis and chemical synthesis, computational chemistry, molecular biology and protein biochemistry to succeed.

uk: вхід без авторизації

name: Taste modifiers – Virtual Screening and Biocatalytic Production with Rationally Opzimized Enzymes


keywords: flow photo

uk: Математика, природничі науки

description: Photolysis of aryl azides generates nitrenes, and their subsequent rearrangement in the presence of water gives 3H-azepinones. The reaction is performed in continuous flow in a photoreactor. Fine tuning of the reaction conditions allows minimization of secondary photochemical reactions. Professor Peter H. Seeberger and his co-workers explain this research result.

uk: вхід без авторизації

name: Continuous flow photolysis of aryl azides: Preparation of 3H-azepinones


Moving molecules by hand

uk: Математика, природничі науки

description: In 1990 the first single atom manipulation experiments were carried out with a scanning probe microscope. The video describes how today, 25 years later, a motion tracking system is used to couple the microscope tip directly to the operator’s hand. Literally moving the tip with their hand, the operator creates a nanoscale structure by removing molecules from a monolayer, although the molecules are bonded strongly to their neighbours. The experiment illustrates the power of intuitive control and demonstrates the possibility of intentional manipulation even when the interactions between the manipulated objects are largely unknown. Music by Alexander Lubeckij (Musiklizenzvereinbarung)

uk: вхід без авторизації


uk: Математика, природничі науки

description: We show you a novel coating method to easily manufacture similar biomimetic large arrays of antireflective moth-eye nanostructures. Optical elements are an important part of many modern-day technical appliances. A major problem of all these optical elements is the reflection of light. These reflections can cause a loss in image brightness, create double images, and might even inflict damage to the equipment. Moths have solved the problem of unwanted light reflectivity millions of years ago using a dense pattern of nano-sized pillars on their eyes. Researchers at the Max Planck Institute for Intelligent Systems in Stuttgart have developed nano.AR, a novel coating method to easily manufacture similar biomimetic large arrays of antireflective moth-eye nanostructures. The project is funded by the BMBF VIP program.

uk: вхід без авторизації

name: nano.AR – technical applications of biomimetic nanostructures


uk: Математика, природничі науки

description: We describe an enantioselective synthetic route to the leucosceptroid family of natural products that allowed to synthesize several members of this natural product familiy. The cotton bollworm (Helicoverpa armigera) and the beet armyworm (Spodoptera exigua) are among the most destructive agricultural pests in nature and they affect vegetables and other crops worldwide. Protection against them has been achieved by the use of sex-pheromone traps, insecticides, and transgenic crops. However, resistance to insecticides has developed over the last decade and new chemical agents are necessary to prevent further crop damage from these pests. Leucosceptrum canum Smith (“Bird’s Coca Cola tree”) and Colquhounia coccinea var. mollisa, plants found in China and Nepal, are remarkably resistant to herbivores and pathogens. Extraction and isolation of the trichomes, flowers, and whole leaves recently led to the discovery of novel antifeedant „leucosceptroid“ natural products. So far, no general and practical strategy which allows for the collective synthesis of the leucosceptroid family of natural products was available to the scientific community. Herein, we describe an enantioselective synthetic route to the leucosceptorids that allowed to synthesize several members of this natural product familiy. Additionally, we were able to partially mimic the biosynthetic pathway and the current findings support the hypothesis that two biosynthetic pathways are operative in the plant. The presented results should also serve as an example that, today, total synthesis is capable of providing practical access to a whole natural product family and deliver ample quantities of important intermediates as wells as the target compounds for further biological investigations.

uk: вхід без авторизації

name: Chemical synthesis of antifeedant – natural products from the coca cola tree


uk: Математика, природничі науки

description: This video should give an insight into the basics of synthesizing nanostructured hybrid materials composed of two different classes of materials, in this case carbon and functional inorganic nanoparticles. These materials are of high interest for current research as they combine the benefits of both material classes. It is usually quite challenging to achieve intimate contact of different materials on the nanometer scale. Non-wovens containing carbon fibers and inorganic nanoparticles can be promising materials for applications in battery systems, sensors and photocatalysis.

uk: вхід без авторизації

name: Conductive textiles of hard matter by electrospinning: Hybrid nanostructures of inorganic nanoparticles and carbon fibers


uk: Математика, природничі науки

description: How can one identify the antibiotic compounds in a complex extract without prior separation? The modern workflow for the functional identification and characterization of bioactive compounds for medicinal or agrochemical purposes is shown featuring a new “reverse metabolomics” method. We start with fungal fruiting bodies, a neglected source of natural products. The process chain with the collection of mushrooms, followed by their extraction, antibiotic and metabolic profiling by mass spectrometry and thereupon based property guided isolation, and eventually structure elucidation spectroscopic methods. The identification of the relevant peaks of the crude extracts thereby is aided by a “reverse metabolomics” process newly developed in our group. It uses algorithms and modern computational methods for an activity-correlation-analysis (AcorA) linking spectroscopic data from metabolic profiles of the fungal extracts to biological activity profiles of the same samples. This approach leads to a more efficient and faster recognition of novel compounds ready for further development toward their environmentally friendly application as drugs or agrochemicals.

uk: вхід без авторизації

name: Natural antibiotics from mushrooms based on metabolic profiling


keywords: biomimetics materials

uk: Математика, природничі науки

description: Plant movements are very suitable as concept generators for biomimetic developments in the fields of deployable and movable structure as used e.g. in architecture or engineering. Plant movements show a multitude of actuation principles causing countless types of form changes in a time range from milliseconds (e.g. suction trap of Utricularia) to hours and days (e.g. different growth processes). Therefore plant movements are very suitable as concept generators for biomimetic developments in the fields of deployable and movable structure as used e.g. in architecture or engineering. Two main topics of research in the Plant Biomechanics Group Freiburg are the analysis of movements driven by changes in turgor pressure, such as the closing of the trap of Dionaea muscipula and the analysis of hygroscopic movements in conifer cones. The principles of the movements, the underlying anatomical features and their biological significance are illustrated. It is also shown how the movements can be analysed quantitatively by recording high speed or time lapse movies under controlled conditions in the lab and under field conditions in combination with macro- und micromechanical testing.

uk: вхід без авторизації

name: Plant movements as concept generators for biomimetic materials and structures


uk: Математика, природничі науки

description: The main research topic related to biomimetics of the Plant Biomechanics Group and the Botanic Garden of the University of Freiburg are presented. These topics comprise (1) branched and unbranched fiber-reinforced structures, (2) highly damping and energy-dissipating materials and structures, (3) attachment and anti-attachment structures and surfaces, (4) smart materials – especially self-repairing materials, (5) deployable and movable structures, and (6) application of biomimetic materials, structures and other bio-inspired technical solutions in architecture. In the greenhouse of the Botanic Garden some of the research projects studied in the Plant Biomechanics Group Freiburg are shortly presented.

uk: вхід без авторизації

name: Biomimetic research in the botanic garden of the University of Freiburg


uk: Математика, природничі науки

description: Branched concept generators such as columnar cacti or arborescent monocotyledons hold a high potential for a biomimetic transfer into technical applications in automotive and constructional engineering. A deepened understanding of the form-structure-function-relationship of these role models is gained by using different methods such as the preparation of thin sections with a microtome for optical analyses and various types of micro- and macro-mechanics testing. Other approaches include the use of a 3D-scanner and 3D-printer for measuring and reconstructing the morphology (form) of the branching. This allows quantifying the influence of the outer and inner structure on the mechanical behavior of the branchings and also understanding which parameters are of importance for the abstraction and implementation into different technical applications, as e.g. nodes in axle carriers or bicycle frames and stringers in airplanes as well as roof-bearing structures

uk: вхід без авторизації

name: From natural to technical branchings: functional analysis as basis for biomimetic transfer


keywords: catalysis rubidium

uk: Математика, природничі науки

description: A Ru-catalyst drives a mobile device for the reversible H2-storage and release. Carbon dioxide and diazabicycloundecene (DBU) are the stoichiometric storage media. The formic acid which is formed within the charging process is a non-toxic and stable liquid that can be stored in bottles or tanks without special precautions.

uk: вхід без авторизації

name: A Ru-catalysis based rechargeable H2-battery


keywords: catalysis iron

uk: Математика, природничі науки

description: The application of a defined iron-hydrogen complex in the dehydrogenative silylation of methanol is reported. The complex (dppp)(CO)(NO)FeH showed a remarkable activity with TOF of more than 600000 h-1 of pure hydrogen gas within seconds. This technology could also be used to run a model hydrogen fuel cell car.

uk: вхід без авторизації

name: Ultrafast “Hydrogen on Demand”-technology by means of iron-catalysis


uk: Математика, природничі науки

description: Some species possess specialized roots or tendrils with adhesive pads allowing them to climb up flat surfaces. This video Presents methods used for analyzing the functional morphology and biomechanics of these attachment systems. Instead of developing a solid trunk, climbing plants use external objects as mechanical support while ascending towards the light. The climbing habit is widespread in the plant kingdom and various attachment systems evolved in different evolutionary lineages. Some species possess specialized roots or tendrils with adhesive pads allowing them to climb up flat surfaces. Methods used for analyzing the functional morphology and biomechanics of these attachment systems are presented. From the results of these investigations the functional principles of the attachment systems and the underlying hierarchical structuring can be identified. This knowledge might help to improve technical anchoring systems by applying biomimetic approaches.

uk: вхід без авторизації

name: Attachment systems of climbing plants: an inspiration for bio-inspired solutions


cs: Matematika

de: Mathematik

fi: matematiikka

uk: Математика

en: Mathematics

fr: Mathématiques

da: Matematik

es: Matemáticas

nl: Wiskunde

uk: Математика, природничі науки

uk: вхід без авторизації

name: The Congruence Subgroup Problem for Automorphism Groups

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

description: In this video clip, Stefan Hecht motivates his group’s research in smart light-responsive materials and explains in simple terms the underlaying principle of photoswitchable molecules. Specifically, he illustrates the main concept of using light to change one form of the photoswitch into another one and vice versa – without the need for sophisticated chemical formulae or physical equations. Finally, he puts this fundamental concept into perspective to his own work carried out in collaboration with other research groups.

uk: вхід без авторизації

name: How do photoswitches work?: The concept behind molecules that can reversibly switched between two different states by light.

name: Beilstein-Institut zur Förderung der Chemischen Wissenschaften


keywords: photo materials

uk: Математика, природничі науки

description: Improving and implementing photoswitches into organic transistors to compute at the speed of light. In this video clip, Stefan Hecht uses the historical setting of Berlin’s Museum of Technology to motivate his research on photoswitchable molecules that act as optically addressable gates in transistor and other devices. He then takes you to the lab, where graduate student Martin Herder explains to you how he prepares and characterizes new molecules with enhanced photoswitching performance. With these molecules in hand and in collaboration with the group of Prof. Paolo Samori in Strasbourg they were able to demonstrate the first prototype photoaddressable transistors. This research open up ample opportunities in optoelectronics as well as sensing applications.

uk: вхід без авторизації

name: Photoswitchable molecules for the next generation devices: Improving and implementing photoswitches into organic transistors to compute at the speed of light.


uk: Математика, природничі науки

description: Springtails (Collembola) are one of the most abundant animal groups on earth, living in virtually all habitats. Due to the fact that they do not breath like other arthropods via trachea but instead by diffusion of oxygen through the skin, a dry and clean surface is one of the requirements for survival. Especially in soil dwelling species or those that live in or on water, highly non-wettable and anti-adhesive surfaces are of great importance. As a consequence, springtails are equipped with the most effective surfaces with respect to wettability repelling not only water, but also oil and several organic solvents, such as chloroform, ethanol, or hexadecane. The specific hierarchical structure based on a hexagonal pattern of nanostructures can be replicated and may serve as a new type of functional surfaces in the future.

uk: вхід без авторизації

name: Springtails – promising templates for robust omniphobic and anti-fouling surfaces


uk: Математика, природничі науки

description: One of the most promising future generation candidates for safe, low-cost and long-lasting high energy density rechargeable energy storage systems is the Lithium-Sulfur (Li-S) battery utilizing sulfur as active material. Sulfur offers the highest theoretical capacity of all known solid-state cathode materials (1672 Ah kg-1) and is, furthermore, widely abundant in nature, inexpensive as well as environmentally friendly. The wide-range application of Li-S batteries as mobile power supply is highly attractive. This video discusses new materials development, production technologies, the potential but also the challenges of the development of stable, high energy Lithium-Sulfur Batteries. Furthermore, the important process steps for the production of these batteries are demonstrated.

uk: вхід без авторизації

name: Lithium-Sulfur Battery: From Materials Development to Production at Fraunhofer IWS


Structure Elucidation without NMR

keywords:
natural products
biology

uk: Математика, природничі науки

description: This video will show how microderivatization of natural extracts containing the target compounds in the ng to μg range can be performed and how the reaction products give additional mass spectral data, helpful for structure elucidation. Structure elucidation of organic compounds present in trace amounts is often needed, e. g. in pheromone research. The target compounds occur in small amounts in difficult to separate mixtures, making isolation of pure samples for NMR experiments unsuccessful. Structure elucidation can then only be performed by GC/MS analysis, derivatization of extracts, and synthesis of proposed structures for structural proof.

uk: вхід без авторизації


keywords: photo polymers

uk: Математика, природничі науки

description: This video demonstrates an easy and fast method for rapid prototyping of medical treatment devices. Burn wounds are very painful and take a very long time to heal. Conventional treatment of burns implies exchange of wound coverages several times per day. By pulsed laser ablation of a metal plate in a water-based monomer solution and simultaneous polymerization, nanoparticles are permanently embedded in a polymer matrix, called microgel. Using electrospinning, these microgels can be easily processed to microfibers for the application as ion-release systems. The release of different bioactive metal ions initiated by the nanoparticles, supports all healing stages and therefore improving the healing process. The presented project is interdisciplinary lead by Prof. Stephan Barcikowski (Chair of Technical Chemistry I at the University of Duisburg-Essen, Vice-Director of the Center for Nanointegration Duisburg-Essen (CENIDE) and Co-founder of the Particular GmbH), Prof. Andrij Pich (Chair of Functional and Interactive Polymers in the DWI-Leibnitz-Institute for Interactive Materials at the RWTH Aachen), Prof. Peter M. Vogt and Prof. Kerstin Reimers (Chair of Plastic, Hand and Reconstructive Surgery at the Hannover Medical School). The principal investigators acknowledge the Deutsche Forschungsgemeinschaft (DFG) for generous founding of the Schwerpunktprogramm 1327.

uk: вхід без авторизації

name: Laser rapid prototyping of bioactive materials for medical treatment


Medicinal inorganic chemistry

uk: Математика, природничі науки

description: This video shows the synthesis and applications of new metal compounds for biomedical applications. We use elements all across the periodic table according to the required properties, for example iron, ruthenium, rhenium or gold. Metal ions play a vital role in biology. They are cofactors in many enzymes, and they even form part of the active center in as much as one third of all enzymes in the human body. Furthermore, metal compounds have an important role for the human well-being. A few metal complexes even serve as drugs, for example against cancer and bacterial infections. However, this field of metal-based drugs is notably less developed compared to purely organic drugs. Our group explores the synthesis and applications of new metal compounds for biomedical applications. We use elements all across the periodic table according to the required properties, for example iron, ruthenium, rhenium or gold. A particular focus of our work is to exploit the unique properties provided by the metal atoms, such as redox activity or optical properties; and to develop highly cell and tissue-specific, targeted metal bioconjugates. The group runs a full research program including not only synthesis but also physical characterization and investigation of their biological properties. This video gives an overview of the various aspects of our work and an outlook to international cooperations in the field of medicinal inorganic chemistry.

uk: вхід без авторизації


Metal-Enhanced Antimicrobial Peptides

uk: Математика, природничі науки

description: There is world-wide a growing resistance of bacteria against common antibiotics. To combat such multi-resistant bacteria, new antibiotics are urgently needed. Antimicrobial peptides (AMPs) are one promising class of novel compounds with the potential to overcome bacterial resistance against established antibiotics. In continuation of our work in medicinal inorganic chemistry, we have successfully modified the activity of short AMPs by substitution with metal complexes. Derivatization of short AMPs with metallocenes yielded not only more active derivatives. Also, depending on the nature of the metallocene and its place within the peptide sequence, we could extend the activity of the conjugate to otherwise resistant strains. In collaboration with microbiologists, the mechanism of action of our new metal-containing AMPs was elucidated. Interestingly, additional activity resides with the redox properties of the metal complex, and their drastically reduced hemolytic activity opens the potential for systemic applications.

uk: вхід без авторизації


Visible light mediated deoxygenations

keywords:
photo
nucleic acids

uk: Математика, природничі науки

description: We introduce here a protocol for deoxygenation of alcohols by photoredoxcatalysis with visible light, which allows the recycling of the activating agent under redoxneutral conditions. About 60 % of all biomass on earth are carbohydrates, i.e. polyhydroxylated compounds. Removing these hydroxyl groups would be desirable to arrive at compounds that might be used as biofuels or that might be further functionalized by chemistry that has been established in the last century based on fossil starting materials (oil and gas). Chemical deoxygenations however are difficult due to the high stability of the carbon-oxygen bond, which requires activation that in turn produce waste in (over)stoichiometric amounts that cannot be easily recycled. We introduce here a protocol for deoxygenation of alcohols by photoredoxcatalysis with visible light, which allows the recycling of the activating agent under redoxneutral conditions. Moreover, in situ activation and deoxygenation is possible in a flow setup, being attractive for large-scale applications.

uk: вхід без авторизації


uk: Математика, природничі науки

description: In this video, we will show you how we produce functional lipid bilayers that mimic biological membranes and allow for the investigation of membrane-confined processes such as they occur in neurotransmission, endo- and exocytosis. To mimic the structure and function of a biological membrane, we make use of highly ordered pore arrays in silicon chips and generate so-called pore-spanning membranes. Such membranes enable us to control and adjust parameters like lipid composition and the membrane’s mechanical properties. Proteins participating in the membrane-confined processes can be isolated and reconstituted into these pore-spanning membranes. This reconstitution allows us to address fundamental biological questions on a molecular level.

uk: вхід без авторизації

name: How lipid membranes meet chip technology


keywords: materials patterning

uk: Математика, природничі науки

description: Synthesis and alignment of three dimensional architectures of carbon nanotubes (CNTs) is demonstrated. Their formation starts from nanoscaled catalysts and interaction with reactive carbon species generated from a hydrocarbon source. The process leads to large spatially oriented CNTs with a high aspect ratio and offers the possibility to transfer these structures to variable substrates. Such CNT nanostructures represent hierarchical materials which allow to bridge the gap from nano to micro to macro dimensions. Engineering the surface of these 3D aligned CNT structures allows tailoring their surface wetting behavior from superhydrophilic to superhydrophobic.

uk: вхід без авторизації

name: Mimicking Natural Surface Wettability with 3D Carbon Nanoarchitectures


uk: Математика, природничі науки

description: We investigate copper based catalysts for the methanol synthesis from CO2 and H2. For a detailed understanding of the structure-performance relation we investigate the interplay between synthesis, microstructure of the catalyst and the resulting Cu-ZnO synergy. Observations at the atomic level and the study of catalytic reaction induced modifications of the catalyst provide feedback towards an optimized synthesis protocol.

uk: вхід без авторизації

name: Nanostructured catalysts for chemical energy storage


keywords: medicinal epibatidine

uk: Математика, природничі науки

description: The video describes the process of the development of a radiopharmaceutical for imaging of Alzheimer´s disease with positron emission tomography. The toxin epibatidine, which was originally derived from a poison arrow frog, is known to bind to various subtypes of nicotinic acetylcholine receptors. Those with an alpha1 subunit are mainly responsible for the toxic action, those with alpha4 and alpha7 subunits are important for Alzheimer´s disease. Structural modification allowed avoidance of the toxic action. The new molecule, called flubatine, contains fluorine in 6-position of a pyridine which was exchanged by the cyclotron-produced positron emitter fluorine-18. Successful in vitro and preclinical in vivo characterization of the radiolabelled flubatine allowed radiopharmaceutical production and use of the compound for PET imaging of patients with Alzheimer´s disease.

uk: вхід без авторизації

name: Toxic epibatidine was structurally modified to image Alzheimer´s disease


uk: Математика, природничі науки

description: We demonstrate that combining the unique properties of superhydrophilicity and superhydrophobicity on the same surface in micropatterns generates unexpected and interesting applications. We use the micropatterns for digital liquid patterning – a simple, maskless method to generate complex water droplets – to create patterns of particles, cells, hydrogels, and complex liquid gradients. We also use the micropatterns to create arrays of thousands of isolated droplets in one simple step. We can confine cells in each individual microdroplet or hydrogel to screening, for example, single cells, non-adherent cells, and cells in 3D microenvironments. We can print different chemicals or bioactive molecules in each superhydrophilic spot and use it as a miniaturized cell screening chip. Other details and examples of applications can be found on www.levkingroup.com

uk: вхід без авторизації

name: Novel applications of superhydrophilic-superhydrophobic patterned surfaces


uk: Математика, природничі науки

description: Our groups deals with different methods for chemical surface patterning with a strong emphasis on biological applications. In this video we show you two methods, micro arraying by microchannel cantilever and Dip-Pen Nanolithography with lipids (L-DPN) as an example of techniques used in our group. One of the applications of these surface patterns is the study of immune cell activation by model allergens. Employing surface patterns in this research gives biologists valuable advantages in regard to experimental control and response read-out.

uk: вхід без авторизації

name: Surface patterning for biological applications


keywords: supramolecules polymers

uk: Математика, природничі науки

description: At presence of molecular oxygen, the energy stored at the triplet ensembles of variety of organic molecules, capable of energy transfer via an emissive process (phosphorescence) or a non-emissive process (triplet-triplet transfer) is actively dissipated. The reason for this is the process of singlet oxygen generation. Importantly, singlet oxygen is a highly reactive species, leading to oxidation of the photoactive molecules, followed by further los of efficiency. In this work we demonstrate organic solvents, specially designed and optimized to deliver long-term protection (over 1000 h) against the molecular oxygen quenching, thus comparable efficiencies of the specific process in oxygen-free environment and under ambient conditions are achieved. Sources: “Long-term stable photoactive composition, such as phosphorescent composition or TTA-photon upconversion composition European patent application: Nr. 13 185 751.8 / 2013

uk: вхід без авторизації

name: Annihilation upconversion in ambient atmosphere


uk: Математика, природничі науки

description: Many nanooptical applications require suitable nanofabrication technology. Hole-mask colloidal nanolithography has proven to be a low-cost and large-area alternative for the fabrication of complex plasmonic nanostructures as well as metamaterials. In this video, we show you the fabrication process step by step in the lab.

uk: вхід без авторизації

name: Fabrication of low-cost and large-area complex nanostructures: The fabrication process step by step


keywords: biochemistry carbohydrate

uk: Математика, природничі науки

description: 5-[18F]Fluoro-5-deoxyribose ([18F]FDR) is a novel monosaccharide radiotracer produced by a two-enzyme biotransformation, at the John Mallard Scottish PET Centre in Aberdeen, UK. The two-step process uses fluorinase, a C-F bond forming enzyme, and a nucleoside hydrolase. In the first step, S-adenosyl-L-methionine (SAM) and [18F]-fluoride are incubated with the fluorinase enzyme. The product of this reaction, [18F]-5′-fluoro-5′-deoxadenosine ([18F]FDA) is incubated with an adenosine hydrolase to generate [18F]FDR. The enzymes were produced and freeze-dried by the O’Hagan group at St Andrews University, and were used on demand by dissolution in water.

uk: вхід без авторизації

name: Enzymatic radiosynthesis of an isotope-labelled halogenated sugar


keywords: biochemistry reaction

uk: Математика, природничі науки

description: The video describes the background to the origin of the fluorinase enzyme from Streptomyces cattleya, which has the ability to form a C-F bond with inorganic fluoride. The presentation describes the isolation and purification of the enzyme and illustrates how it can be used, in a two-enzyme reaction, to prepare [5-18F]-5-fluoro-5-deoxyribose ([18F]-FDR). The sugar [18F]-FDR emerges as an excellent ligand for bioconjugation to clinically significant peptides. Moreover, it holds promise as a new methodology for labelling peptides with the fluorine-18 isotope, for application in clinical imaging by positron emission tomography (PET).

uk: вхід без авторизації

name: Enzymatic fluorination: The fluorinase enzyme from Streptomyces cattleya


keywords: reactions olefin

uk: Математика, природничі науки

description: Olefin Metathesis is one of the most important reactions in synthetic chemistry. This powerful synthetic tool renders accessible complex molecules that are very tedious to synthesize using traditional organic synthetic methods. As a testimony to its importance, metathesis reactions are now employed to access fine chemicals, biologically active compounds, new functionalized materials, and various polymers. In this video we showcase the synthesis of a Ruthenium Indenylidene complex and its use in ring-closing metathesis (RCM).

uk: вхід без авторизації

name: Olefin metathesis – ring-closing reaction


uk: Математика, природничі науки

description: Chemo-enzymatic approaches provide powerful tools for labeling distinct biomolecules specifically, even within living cells. Apart from proteins and DNA also tRNA and pre-mRNAs have been modified successfully. In our group we established a chemo-enzymatic strategy for specific modification of eukaryotic mRNAs. For this purpose, we made use of a Tgs variant, capable of transferring alkenyl- or alkynyl- residues specifically to the mRNA cap. The enzymatically labeled structure was then amenable to modification by different click reactions, such as thiol-ene or CuAAC. This strategy could provide a novel basis for modifying eukaryotic mRNAs in living cells, making this species accessible for isolation or visualization. Methods (from Supplement) Enzymatic modification of cap-analogue m7GpppA For enzymatic modification the cap analogue m7GpppA (1 mM) was incubated with AdoPropen (0.5-1 mM) respectively AdoEnYn (360-740 µM) in presence of GlaTgs2 or variant (5-120 µM) as well as 4 µM MTAN and 3 µM LuxS in PBS (pH 7.4) or PUS buffer (without DTT) at 37 °C for 3 hours. Reactions for subsequent use in TEC were stopped by adding 1/10 volume 1 M HClO4, those for CuAAC were stopped by heating samples for 15 min at 68 °C, followed by dialysis against PUS buffer (with 5 mM DTT) for 15 min. Enzymatic conversions were analyzed by HPLC after protein precipitation with 1 M HClO4 on an analytical NUCLEODUR® C18 Pyramid (5 μm, 125×4 mm). Thiol-Ene Click reaction In situ generated N2-allyl-m7GpppA was used for TEC after protein precipitation without any further purification. Samples were degassed with argon before biotin-thiol 6 (40 mM) and VA-044 (800 µM) were added. Reactions were performed for up to 8 h at 44 °C under exclusion of oxygen. Afterwards samples were analyzed by reversed-phase HPLC. CuAAC with RNA RNA is generated by in vitro transcription using T7 polymerase, purified by phenol:chloroform extraction and precipitated using 2-propanol. RNA is resuspended in PBS and concentration is determined by in-gel quantification. For our experiments RNA solutions with about 19 µg/µL worked best. Capping of transcribed RNA is achieved with the vaccinia capping system (NEB) In detail, 0.9 nmol RNA were allowed to react with GTP (10 nmol) and vaccinia capping enzyme (20 U) with or without AdoMet (2 nmol) in a final volume of 20 µL for 1 h at 37 °C. Make sure to use the correct concentration of RNA in this step. Afterwards samples were heated for 15 min at 65 °C and incubated 15 min at 4 °C with cation exchanger P11 cellulose phosphate (Whatman). Supernatant was precipitated and pellet was resuspended in GlaTgs2-Var1 (37-49 µM), MTAN (1.2 µM), LuxS (0.6 µM, all purified using an ÄKTA purifier™ system and HisTrap™ FF 1 columns (GE Healthcare)), AdoEnYn (2, 1.5-1.7 mM) in the presence of 0.25 µL RiboLock RNase Inhibitor (Thermo Scientific) and adjusted to a final volume of 5 µL with PUS buffer. If labeling is not successful it can help to increase AdoEnYn concentration in this step and to make sure that labeling efficiency with GlaTgs variant is sufficient using a cap-analogue as substrate. Samples are then incubated for 90 min at 37 °C, RNA is precipitated and used for CuAAC. For this, RNA is resuspended in PUS-buffer containing 5 mM DTT (4 µL), 3.2 µL Click solution (DMSO:tBuOH 3:1; Jenaobioscience) is added as well as 0.8 µL of a 2.5 mM Eterneon-azide solution CuBr (stored in a glovebox) is solved in Click solution to give a concentration of 300 mM and immediately diluted in a 111 mM TBTA to give a final CuBr concentration of 30 mM. The Cu/TBTA solution (1.2 µL) is added to the RNA, which is then incubated at 37 °C for 1 hour. Samples are analyzed on 10 % denaturing gels

uk: вхід без авторизації

name: A chemo-enzymatic approach for site- specific modification of the RNA cap


uk: Математика, природничі науки

description: Asymmetric localization of mRNA is a mechanism to regulate gene expression spatially as well as temporally. To study localization mechanisms various probes for RNA imaging have been established. Protein-based probes fused to split fluorescent reporters are suitable, since they can be expressed by the cellular machinery. Sequence-specific binding of proteins to their target RNA and subsequent reconstitution of the fluorescent reporter allow RNA detection. However, the traditional fluorescent reporters based on split-GFP are large and self-assemble spontaneously, causing significant background. To circumvent these limitations we used the three-body split-GFP by Geoffry Waldo at Los Alamos Labs and developed the Tetramolecular Fluorescence Complementation (TetFC) reporter system for detection of specific RNAs in vitro. In this video we show the concept of this system and how it is performed in the laboratory. The detection of a specific RNA is monitored via fluorescence intensity measurements and in-gel fluorescence. We thank the “Sea Life Deutschland GmbH” for the opportunity to film at the SEA LIFE Timmendorfer Strand. The jellyfish shown in this video is Aurelia aurita (and not Aequorea victoria from which GFP was first isolated).

uk: вхід без авторизації

name: Beilstein-Institut zur Förderung der Chemischen Wissenschaften


uk: Математика, природничі науки

description: In biological systems, adhesive organs used for attachment to substrates as well as those involved in catching prey, demonstrate a huge diversity of their structural properties. Remarkably, these highly-specialized structures are not restricted to one particular area of the body and operate due to various combinations of physical principles. The research at the Functional Morphology and Biomechanics group at the Zoological Institute at the Kiel University combines approaches of several disciplines: zoology, botany, structural biology, biomechanics, physics, and materials science. Using a wide variety of methods, we study mechanical systems and materials, which emerged during biological evolution. Some of these adhesive systems employ secretory substances, modulating forces in the contact area, or bear the capability of operating underwater. In order to explore different functional principles, we experimentally test many different systems and try to outline general rules of the interrelationship between structure and function. Since comparative studies on the microsculpture, ultrastructure, material properties, and attachment-detachment performances of several functional systems include a wide variety of organisms, some questions about the evolution of these systems can be resolved. Our studies aid in finding interesting structure-function relationships, which can be used for technical applications. Recently, together with the company Binder (Holzgerlingen, Germany) we developed an adhesive tape, which is capable of adhesion enhancement on flat surfaces by the use of bioinspired surface microstructures.

uk: вхід без авторизації

name: Biological and biologically inspired adhesives


uk: Математика, природничі науки

description: In this video the authors present asymmetric organocatalyses performed in a ball mill. Three reaction types are being discussed: enantioselective aldol reactions, asymmetric Michael additions to nitro alkenes and dipeptide formations. In the laboratory the ball milling device is shown, and reaction details are revealed. Finally, future applications of mechanochemical biomass degradations are highlighted.

uk: вхід без авторизації

name: Asymmetric organocatalysis in a ball mill


uk: Математика, природничі науки

description: The video describes the discovery of mbandakamine A, a dimeric naphthylisoquinoline alkaloid isolated from a ‘new’, botanically yet undescribed Ancistrocladus species. This liana grows in the tropical rain forest of the Congo Basin – and has now been cultivated for the first time in the greenhouse of the Botanical Garden of Würzburg: a worldwide unique cultivation success. The absolute stereostructure of mbandakamine A was elucidated by modern spectroscopic methods like MS, NMR, and CD (circular dichroism), in part hyphenated with HPLC, and was confirmed by quantum-chemical CD calculations. Besides its novel structure and the unprecedented biosynthetic origin, mbandakamine A also shows good activity against the malaria parasite, which was determined in the SFB 630 network, involving scientists from chemical, pharmaceutical, biological, and medicinal research groups.

uk: вхід без авторизації

name: Mbandakamine A, a unique alkaloid from an african liana


keywords: electronics medicinal

uk: Математика, природничі науки

description: Stroke is the third leading cause of death in the Western world. More than 140 000 people die each year from stroke in the US. Patients are treated by catheter based surgery. We developed a light-switchable MRI contrast agent to visualize blood-vessels. Switching is performed with an optical fiber that guides the light from the light source to the site of intervention. Stroke is the third leading cause of death in the Western world. More than 140 000 people die each year from stroke in the US. Patients are treated by catheter based surgery. The catheter is introduced through a large artery (usually upper leg) and pushed into the brain to remove blood clots, or to stop bleeding. All manipulations are performed under imaging control using X-ray. We developed a light-switchable MRI contrast agent to visualize blood-vessels. Switching is performed with an optical fiber that guides the light from the light source to the site of intervention. Potential advantages are i.a. no radiation exposure, lower concentrations and 3D-imaging. The contrast agent is based on a nickel-porphyrin to which a switchable ligand is attached. It is the first molecule whose spin state can be reversibly switched at room temperature. Further developments are aimed at MRI contrast agents that are responsive to pH, temperature, and other parameters for the early detection of inflammation and cancer.

uk: вхід без авторизації

name: The world’s smallest switchable magnet and its application in medical diagnostics


uk: Математика, природничі науки

description: In this video, the DNA building block chemistry is described with respect to the modification of DNA by chromophores. Photoswitches as chromophores allow photoinduced color changes in DNA. Combination of two different chromophores enable DNA (i) to display strand displacement by fluorescence color changes, e.g. from green to red and vice versa, and (ii) to act as light harvesting systems.

uk: вхід без авторизації

name: Synthesis of DNA with optical functionalities


Sugar hydrogels as biosensors

uk: Математика, природничі науки

description: The video presents a collaboration project between the MPI of Colloids and Interfaces (MPIKGF) and Universität Leipzig on the synthesis of a new class of sugar presenting scaffolds and a novel label free screening method to determine biomolecular interactions. Carbohydrates are not merely a source of our nutrition. Many sugars are bioactive in that their structure contains molecular information that is recognized by cell receptors to control various important biological functions, such as cell signaling and immune response. Therefore, the synthesis of complex sugars containing the “right” information and understanding their biomolecular interactions is crucial to the advances in biomedicine and related areas.

uk: вхід без авторизації


uk: Математика, природничі науки

description: Gluons are the smallest adhesive particles; they hold the quarks together inside atomic nuclei. To-date no-one has been able to view an object made only of gluons – a glueball. Concettina Sfienti and many other scientists want to achieve this for the first time using the PANDA detector in the FAIR accelerator system, which is currently being built. A very special ingredient shall lead them to the goal: antimatter.

uk: вхід без авторизації

name: Antimatter: On the trail of the glueballs


uk: Математика, природничі науки

description: Neutron stars are extraordinary objects in the universe. Their density is so high that atoms melt within them and new states of matter arise. Tetyana Galatyuk and her colleagues try to simulate these conditions at the smallest scale using the FAIR particle accelerator and observe the results with the CBM detector. Thus, they not only learn more about neutron stars, but also about the innermost structure of matter.

uk: вхід без авторизації

name: Neutron stars – a melting pot for atomic nuclei


uk: Математика, природничі науки

description: The gold found on Earth is to a large extent the product of supernovae. Other elements are also created during these violent astrophysical explosions. Karlheinz Langanke and his colleagues at GSI carry out research into the nucleosynthesis process. Here, an important role is played by the super fragment separator; a construction made of huge magnets which acts like a sieve, filtering out the nuclei of interest from a large mixture.

uk: вхід без авторизації

name: Creation of elements – supernova in the lab


uk: Математика, природничі науки

description: Tumors can be treated using ion-beam radio-therapy. Ions are accelerated to precisely controlled speeds in a particle accelerator. They penetrate into the body, almost without harming healthy tissue until their energy is released in the tumor destroying the malignant cells. Robert Kaderka explains how this therapy works and how he and his colleagues at the GSI biophysics department are further developing the method.

uk: вхід без авторизації

name: Tumor therapy – Fast ions in the fight against cancer


uk: Математика, природничі науки

description: All experiments at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany need fast particles. Jens Stadlmann operates and develops accelerators. He explains how ions are produced, how they reach high speeds in linear and circular accelerators, and what the new FAIR accelerator facility that is being built will be able to achieve.

uk: вхід без авторизації

name: How does an accelerator for heavy ions work?


keywords: reactions methods

uk: Математика, природничі науки

description: Six new chemical elements were produced at GSI. Sigurd Hofmann is one of the discoverers and shows how sophisticated you have to be to create a new element. His ingredients: fast ions from a particle accelerator, a target and a very accurate measuring instrument.

uk: вхід без авторизації

name: New elements – Alchemy with the accelerator


uk: Математика, природничі науки

description: Marguerite Clyne talks about research activities that she and collaborators are working on to try and elucidate which carbohydrate molecules present on mucin glycoproteins and on milk sugars act to prevent the bacteria Campylobacter jejuni, an important cause of food poisoning in humans, from causing disease. They are looking at sugars present on mucin purified from chicken mucus, as C. jejuni can live in chickens but the chickens do not get sick. Chicken mucins can prevent C. jejuni from interacting with epithelial cells. Interestingly, sugars present in the colostrum of cows can also prevent C. jejuni from entering the human cell. Current work aims to discover which sugars present in mucin and milk prevent C. jejuni from entering the cells. These sugars have the potential to be added as ingredients to certain foods in order to prevent infection against C. jejuni and possibly other bacteria that also cause disease.

uk: вхід без авторизації

name: Carbohydrate molecules as a potential means to prevent food poisoning


keywords: glycomics biochemistry

uk: Математика, природничі науки

description: Stephen Carrington talks about work that he and collaborators are undertaking to try and interrogate the complex array of carbohydrate structures present on mucin glycoproteins. These glycoproteins form part of the mucus gels that protect moist mucosal surfaces from microbial assault. Mucin glycoproteins can potentially act in two ways. Firstly, they can block the adhesins that are required for binding by harmful microbial pathogens to mucosal surfaces. Secondly, they can act as a food source for beneficial microbial colonisers that can compete with potential pathogens. We believe that these sugars represent a natural resource that can be mined for specific structures to be used to prevent harmful infections. This is because these structures represent the product of evolutionary drivers that lead to the construction of an effective barrier containing biologically engineered arrays of sugar structures that function in defense.

uk: вхід без авторизації

name: Mucin glycoproteins – a complex array of carbohydrate structures


An introduction to immunoglobulin G

uk: Математика, природничі науки

description: This video describes the immunoglobulin G antibody and its role in the immune response. The structure of the antibody and the importance of its associated carbohydrates are described in detail. Binding of immunoglobulin G to membrane-bound receptors on the surface of immune cells such as B cells, macrophages and natural killer cells leads to initiation or inhibition of an immune response. This process is critical to protect us against infection and cancer through biological processes such as antibody-dependent cellular cytoxicity. Also discussed is how the biopharmaceutical industry is now exploiting antibodies and their properties to provide new treatment options for various diseases. These therapeutic monoclonal antibodies exploit the body’s own immune system in so-called immunotherapy.

uk: вхід без авторизації


uk: Математика, природничі науки

description: All cells in the body are heavily coated with sugars, a process known as glycosylation. Changes in cellular glycosylation are a recognized feature of many cancers, such changes often being associated with more aggressive behavior and a tendency to spread or metastasize to distant sites. Until recently little was known of the role of glycosylation in the progression of the blood cancer multiple myeloma. Our work reveals that glycosylation-related genes are abnormally expressed in multiple myeloma. In particular, we have found that overexpression of an important glycosylation gene called ST3GAL6 is associated with more aggressive disease and poor prognosis in patients with multiple myeloma. We believe that ST3GAL6 may be a new biomarker of progression as well as a potential therapeutic target.

uk: вхід без авторизації

name: Investigating the role of glycosylation in multiple myeloma


Examining glycosylation changes

uk: Математика, природничі науки

description: Professor Lokesh Joshi talks about the association of glycosylation changes with diseases and new diagnostic and prognostic targets that are developed. In particular, he speaks about the examination of which glycosylation genes are turned up and down in a disease and measurements thereof by means of a microarray analysis.

uk: вхід без авторизації


uk: Математика, природничі науки

description: This presentation illustrates the use of (NP)-HPLC analysis to determine galactose incorporation into serum IgG, used as a biomarker for the improved monitoring and treatment of patients with Galactosaemia. Classical or severe Galactosaemia is a genetic condition caused by a lack of the enzyme Galactose-1-phosphate uridyltransferase (GALT), which normally breaks down galactose (the sugar found in milk and dairy products). This occurs in approximately 1:60,000 births annually in Europe but has a higher incidence in Ireland of 1:16,000 births where it is detected by newborn screening. Despite early treatment, the majority of affected patients worldwide go on to develop devastating long-term complications such as intellectual impairment, neurological complications, speech difficulties and infertility in females. These complications may be associated with abnormal synthesis of N-glycoproteins.

uk: вхід без авторизації

name: Identification of glycosylation abnormalities in galactosaemia


Carbohydrate modeling: a twisted tale

uk: Математика, природничі науки

description: This video outlines the role of computational simulations in the design of carbohydrate-based therapeutic agents, such as antibacterial vaccines and antiviral drugs

uk: вхід без авторизації


uk: Математика, природничі науки

description: The video shows the NIBRT Training Team in the pilot plant, as they detail the step-by-step manufacturing processes for the production of biotherapeutics. The National Institute for Bioprocessing Research and Training (NIBRT) replicates a modern bioprocessing plant with state-of-the-art equipment for the production and analysis of biopharmaceuticals, such as therapeutic monoclonal antibodies (mABs). The video shows the NIBRT Training Team in the pilot plant, as they detail the step-by-step manufacturing processes for the production of biotherapeutics. This is followed by a summary of the analytical technologies used by the NIBRT Glycobiology Research Group to analyse the sugars or “glycans” present on the biopharmaceuticals.

uk: вхід без авторизації

name: Bioprocessing and protein glycosylation analysis


uk: Математика, природничі науки

description: Many enzymatic transformations are utilized in the biosynthesis of the monoterpene indole alkaloids, a group of structurally diverse natural products. Here we describe the discovery, functional characterization and mechanistic study of several enzymes involved in the biosynthesis of the monoterpene indole alkaloids in Catharanthus roseus. Also discussed are the implications of this work in the metabolic engineering of natural products.

uk: вхід без авторизації

name: Chemistry and biology: alkaloid biosynthesis in plants: Elucidating and Engineering Natural Product Pathways in Plants

name: Beilstein-Institut zur Förderung der Chemischen Wissenschaften


keywords: reactions biochemistry

uk: Математика, природничі науки

description: This video highlights the importance of cytochrome P450s in academia and industry and explains how our research group broadens the substrate range of these biocatalysts through enzyme engineering. We showcase a typical high-throughput assay and describe our procedure for carrying out whole-cell biotransformations.

uk: вхід без авторизації

name: Expanding the toolbox of cytochrome P450s through enzyme engineering


uk: Математика, природничі науки

description: This video shows how we can achieve chemical and biochemical reactions on conducting surfaces and monitor these reactions in situ using MALDI-TOF mass spectrometry.

uk: вхід без авторизації

name: Chemical reactions on conducting surfaces


keywords:
systems biology
biotechnology

uk: Математика, природничі науки

description: Prof. Douglas Kell talks about systems biology, computational aspects of biochemistry, and drug discovery, as well as open-access publishing and the communication of research results. The questions were prepared and asked by Prof. Roy Goodacre.

uk: вхід без авторизації

name: Perspective on e-science, systems biology and drug discovery