Early Step toward Treatment for Diseases that Affect Blood Flow
University of Utah bioengineers showed that tiny blood vessels grow better in the laboratory if the tissue surrounding them is less dense. Then the researchers created a computer simulation to predict such growth accurately – an early step toward treatments to provide blood supply to tissues damaged by diabetes and heart attacks and to skin grafts and implanted ligaments and tendons.
“Better understanding of the processes that regulate the growth of blood vessels puts us in a position ultimately to develop new treatments for diseases related to blood vessel growth,” and to better understand cancer metastasis, says bioengineering professor Jeff Weiss of the university’s Scientific Computing and Imaging Institute. (more…)
Heute steht fest, dass alle Wirbeltiere, die über einen Kiefer verfügen, auch vier Flossen oder Gliedmaßen haben – ein Paar vorne und eines hinten. Das war nicht immer so: Im Laufe der Evolution hat sich die Anordnung von Flossen, Flügeln, Armen und Beinen verändert. Trotzdem gaben sich bereits unsere frühesten Vorfahren mit der gleichbleibenden Anordnung von zwei Paar Gliedmaßen zufrieden: Warum? Weil wir einen Bauch haben! Ein Forschungsteam der Universität Wien und des Konrad-Lorenz-Instituts stellt zu dieser Fragestellung eine neue Studie in der internationalen Zeitschrift “Evolution & Development” vor.
Wie bei vielen ungeklärten Fragen in der Evolutionsbiologie entstanden im Laufe der Zeit mehrere hypothetische Modelle, um den Ursprung der paarigen Gliedmaßen bei den Kiefermäulern – im Fachjargon Gnathostomata – zu erklären. Unter Kiefermäuler versteht man alle Tiere mit Rückgrat und Kiefer, sowohl die lebenden als auch die ausgestorbenen. “Ausgenommen davon sind jedoch Neunaugen und Schleimaale. Obwohl diese beiden Fischarten weder über Kiefer noch paarige Flossen verfügen, sind bei ihnen vom Rücken bis zum Schwanz entlang der Mittellinie Rückenflossen vorhanden”, sagt Brian Metscher vom Department für Theoretische Biologie der Universität Wien. Jeder Erklärungsansatz, warum das so ist, muss nicht nur die fossilen Belege berücksichtigen, sondern auch die Feinheiten der frühen Entwicklung von Flossen und Gliedmaßen.(more…)
AUSTIN, Texas — As the male túngara frog serenades female frogs from a pond, he creates watery ripples that make him easier to target by rivals and predators such as bats, according to researchers from The University of Texas at Austin, the Smithsonian Tropical Research Institute (STRI), Leiden University and Salisbury University.
A túngara frog will stop calling if it sees a bat overhead, but ripples continue moving for several seconds after the call ceases. In the study, published this week in the journal Science, researchers found evidence that bats use echolocation — a natural form of sonar — to detect these ripples and home in on a frog. The discovery sheds light on an ongoing evolutionary arms race between frogs and bats. (more…)
98 Prozent der festen Materie unseres Planeten bestehen aus Kristallen, doch ist die häufigste Erscheinungsform von Festkörpern in der öffentlichen Wahrnehmung kaum präsent. Ein von der UNO initiiertes Jahr der Kristallographie soll dieser „Vernachlässigung“ ein Ende bereiten. Der Innsbrucker Mineraloge Volker Kahlenberg ist einer der Koordinatoren der Aktivitäten in Österreich. (more…)
Heralding a new age of terrific timekeeping, a research group at JILA—a joint institute of the University of Colorado Boulder and the National Institute of Standards and Technology—has unveiled an experimental strontium atomic clock that has set new world records for both precision and stability.
The clock is in a laboratory at JILA, located on the CU-Boulder campus. (more…)
Researchers at Berkeley Lab’s Advanced Light Source Find New Form of Quantum Matter
The discovery of what is essentially a 3D version of graphene – the 2D sheets of carbon through which electrons race at many times the speed at which they move through silicon – promises exciting new things to come for the high-tech industry, including much faster transistors and far more compact hard drives. A collaboration of researchers at the U.S Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered that sodium bismuthide can exist as a form of quantum matter called a three-dimensional topological Dirac semi-metal (3DTDS). This is the first experimental confirmation of 3D Dirac fermions in the interior or bulk of a material, a novel state that was only recently proposed by theorists. (more…)
Why did life forms first begin to get larger and what advantage did this increase in size provide? UCLA biologists working with an international team of scientists examined the earliest communities of large multicellular organisms in the fossil record to help answer this question. (more…)
North Carolina State University researchers have used silver nanowires to develop wearable, multifunctional sensors that could be used in biomedical, military or athletic applications, including new prosthetics, robotic systems and flexible touch panels. The sensors can measure strain, pressure, human touch and bioelectronic signals such as electrocardiograms.
“The technology is based on either physical deformation or “fringing” electric field changes. The latter is very similar to the mechanism used in smartphone touch screens, but the sensors we’ve developed are stretchable and can be mounted on a variety of curvilinear surfaces such as human skin,” says Shanshan Yao, a Ph.D. student at NC State and lead author of a paper on the work. (more…)
