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Dennis Kunkel Microscopy - Electron Microscopy Science Stock Photography

Dennis Kunkel Microscopy - Electron Microscopy Science Stock Photography

Biology Animations Carnegie Mellon's Office of Technology for Education and Department of Biological Sciences create multimedia materials for teaching and learning Biology. After an analysis of a number of Biology courses was performed to identify when and how shared concepts where taught, a team of biologists, media programmers, and learning experts came together to create animations designed to improve understanding of some of the main concepts taught in Modern Biology and Biochemistry. Phosopholipid Membranes Tutorial page describing the construction and properties of Biological Membranes. Biological Membranes Biological membranes are dynamic structures composed of a diverse set of phospholipid molecules and proteins. Phase Transition This tutorial explains how phospholipids bilayers undergo to a cooperative phase transition or melting that is similar to protein denaturation. back to index Signal Transdaction Serine Protease Uniport - Glucose Transport Symport - Lactose Permease Transporter ATP Synthesis

Expériences Scientifiques sur l’Environnement et la Biologie Giorgio Carboni, Décembre 2000 Traduit par Caroline Varin en Janvier 2009 Plusieurs lecteurs nous ont écrit pour avoir plus d’expériences et pour savoir comment construire des jouets. Comme nous avons besoin de quelques mois pour compléter un article, nous avons pensé à collecter des sujets intéressants, à les pourvoir d’une brève description et à les relier à des sites qui existent déjà. De cette manière, nos lecteurs peuvent rapidement trouver plus d’activités intéressantes et amusantes. Les expériences que nous avons rassemblé dans cet article concernent essentiellement la biologie et l’environnement. Au fur et à mesure que le temps passe, nombres des liens que nous avons proposés vont disparaître, et d’autres sites vont naître. AVERTISSEMENTS: certaines de ces expériences peuvent être dangereuses. Amusez vous bien ! En utilisant un tamis avec des trous de 2 mm de diamètre, vous pouvez séparer les graviers du sable et déterminer leur proportion.

Home of CELLS alive! Spinning-disk microscope offers window into the center of cell A new method of imaging cells is allowing scientists to see tiny structures inside the 'control centre' of the cell for the first time. The microscopic technique, developed by researchers at Queen Mary University of London, represents a major advance for cell biologists as it will allow them to investigate structures deep inside the cell, such as viruses, bacteria and parts of the nucleus in depth. Recent advances in optical physics have made it possible to use fluorescent microscopy to study complex structures smaller than 200 nanometres (nm) -- around 500 times smaller than the width of a human hair. These methodologies are called super-resolution microscopy. The drawback of such techniques is that they can only produce very clear images of structures that are at the bottom of the cell. This study shows how these issues have been overcome with a newly developed imaging system, making it possible to image structures as small as 80nm or less anywhere in the cell.

Make your own cartoons and animations easily. Our tools are free and you don't need to learn Flash. Bats Use Rolled-Up Leaves as “Trumpets” By Ker Than- A species of tiny bat seems to be using rolled-up leaves like trumpets to amplify calls, a new study says. A few years ago, biologists Gloriana Chaverri and Erin Gillam were in Costa Rica studying Spix’s disk-winged bat, a species that is known to escape predators and harsh weather by roosting inside the folded leaves of plants such as the lobster-claws plant and calatheas. Disk-winged bats inside leaves on Barro Colorado Island, Panama. The creatures are so small—each one weighs only about four grams—that multiple bats can fit inside a single leaf. While studying the bats, the scientists noticed that individuals roosting inside leaves often could not recognize calls made by members of their own group flying outside. “Then, given the shape of the leaf, we began to wonder if the leaves could increase sound intensity while affecting fidelity, much like acoustic horns do.” Hear, Hear Say What? However, roosting bats also make their own unique call, called a “response” call.

welcome - library.nu Report suggests slowdown in CO2 emissions rise 31 October 2013Last updated at 05:19 ET By Matt McGrath Environment correspondent, BBC News Carbon emissions from coal fired plants like this one continue to increase but at a lower rate than previous years Global emissions of carbon dioxide may be showing the first signs of a "permanent slowdown" in the rate of increase. According to a new report, emissions in 2012 increased at less than half the average over the past decade. Key factors included the shift to shale gas for energy in the US while China increased its use of hydropower by 23%. However the use of cheap coal continues to be an issue, with UK consumption up by almost a quarter. The report on trends in global emissions has been produced annually by the Netherlands Environment Assessment Agency and the European Commission's Joint Research Centre. It finds that emissions of carbon dioxide reached a new record in 2012 of 34.5bn tonnes. But the rate of increase in CO2 was 1.4%, despite the global economy growing by 3.5%. Breaking the link

Καλώς ήρθατε στην ιστοσελίδα wiki του ΠΕΙΡΑΜΑΤΙΚΟΥ ΛΥΚΕΙΟΥ ΑΓ.ΑΝΑΡΓΥΡΩΝ - ΠΕΙΡΑΜΑΤΙΚΟ ΛΥΚΕΙΟ Un scorpion de 350 millions d'années découvert dans l'hémisphère sud | Découvertes La nouvelle espèce, baptisée Gondwanascorpio emzantsiensis, est la plus ancienne forme de vie jamais trouvée sur la terre ferme de l'hémisphère sud, affirme Wits dans un communiqué. Il vécut à la fin du dévonien (-400 millions d'années.) Le Gondwana était un supercontinent (-600 millions d'années) essentiellement situé dans l'hémisphère sud et regroupant les actuelles Amérique latine, Afrique, Antarctique, Australie, péninsule arabique et sous-continent indien. «Nous n'avions jusqu'à présent aucune preuve que le Gondwana était habité par des animaux invertébrés à cette époque», a assuré le professeur Robert Guess, de l'institut des études de l'évolution à Wits. Le fossile, dont on distingue clairement une pince et le dard, a été découvert près de Grahamstown, dans la province du Cap oriental dans le sud de l'Afrique du Sud. Les premiers vertébrés, dont sont issus les mammifères et donc les humains, sont apparus sur terre il y a environ 350 millions d'années.

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