Erosion theory explains uniform patterning of landscapes.
The fledgling European Research Council is struggling against the constraints imposed by the European Commission. It needs to be completely independent.
Earth's disturbed ecosystems have much more to offer than many would give them credit for.
Scientists need better Earth-monitoring tools to see whether climate policies are working.
European Research Council finds itself mired in bureaucracy.
US psychiatrists divided by claims of secrecy and scientific overreach.
Rich countries' pandemic strategies may cause vaccine shortages elsewhere.
Breaking the barriers proves to be a slow process.
A small group of ecologists is looking beyond the pristine to study the scrubby, feral and untended. Emma Marris learns to appreciate 'novel ecosystems'.
Maurice Strong has shaped how nations respond to planetary crises. Ehsan Masood meets the man whose successes — and failures — laid the groundwork for the current climate talks.
Venture funding is declining quickly and is unlikely to bounce back. But less money means lower expectations — good news for smaller science start-ups, says John Browning.
A book setting out the ten greatest transformations delivered by evolution contains surprises but neglects crucial innovations such as proteins and embryos, Lewis Wolpert finds.
An investigation of lakes in Sweden has delivered results that run counter to the idea that primary production is generally limited by the availability of nutrients. There are lessons for limnologists in this.
The idea that physical phenomena might be described by a more downto-earth theory than quantum physics has met with resistance from many physicists. Indeed, it seems that nature is not as simple as we would like.
It's hard to fit in when you're different — especially if you're a large particle trying to squeeze into an array of smaller ones. But some soft, polymeric particles simply shrink to fit the space available.
The core domain of the p53 protein has been found to affect microRNA processing — its third known antitumour activity. Most cancerous p53 mutations affect this domain and may abolish all tumour-suppressor functions.
Why, in many landscapes, does ridge–valley spacing show such regularity? The combination of high-resolution data and an elegant model offers a solution to this long-standing puzzle, for some cases at least.
If complex tissues are to be engineered, synthetic materials will be needed that provide cells with precisely located molecular cues. A method that attaches such cues to specific areas of a gel could be the answer.
Simian immunodeficiency virus is associated with increased mortality in a subspecies of chimpanzee living under natural conditions in East Africa. This is worrying news for the chimpanzee populations involved.
During spermiogenesis, canonical histones are largely exchanged for protamines, and whether the rarely retained nucleosomes have any function has been unclear. Here, high-resolution genomic approaches are used to localize the nucleosomes retained in mature human sperm; they are found to be significantly enriched at developmentally important genes and to have distinctive patterns of histone modifications.
MicroRNAs (miRNAs) are short RNAs that are ubiquitous, potent regulators of gene expression; however, as miRNA activity requires base pairing with only 6–8 nucleotides of messenger RNA, predicting target mRNAs is a major challenge. By using a method known as HITS-CLIP, combined with bioinformatic analysis, it has now been possible to demonstrate how the in vivo interactions between miRNAs and the mRNA targets can be validated.
Jets of water ice from surface fractures near the south pole of Saturn's icy moon Enceladus produce a plume of gas and particles. The source of the jets may be a liquid water region under the ice shell. Here, ammonia is reported to be present in the plume, providing strong evidence for the existence of at least some liquid water.
It is commonly assumed that the aurora borealis (Northern Hemisphere) and the aurora australis (Southern Hemisphere) are mirror images of each other. Here, observations are reported that clearly contradict this common assumption: intense spots are seen at dawn in the Northern summer Hemisphere, and at dusk in the Southern winter Hemisphere.
The question of whether quantum phenomena can be explained by classical models with hidden variables is the subject of a long-lasting debate. One feature of classical models that is thought to be in conflict with quantum mechanics is non-contextuality, with experiments undertaken with photons and neutrons seeming to support this. However, these tests required the generation of special quantum states and left various loopholes open. Here an experiment is performed with trapped ions that overcomes these problems and cannot be explained in non-contextual terms.
Cup-shaped molecules of calixhydroquinone self-assemble on a surface into a lens shape; these lenses are shown to generate near-field magnification beyond the diffraction limit, enabling the resolution of features of the order of 200 nanometres. Such spherical nanolenses provide new pathways for lens-based near-field focusing and high-resolution optical imaging at very low intensities, which are useful for, among other things, bio-imaging and near-field lithography.
Ridges and valleys in many landscapes are uniformly spaced, but no theory has predicted this fundamental topographic wavelength. A characteristic length scale is now derived from equations of mass conservation and sediment transport; it is found to be directly proportional to the valley spacing in models of landform evolution, and to the measured valley spacing at five study sites in the USA.
Lake ecosystem productivity, defined by the rate of biomass synthesis, is believed to be limited by nutrient availability. However, the comparison of several small unproductive lakes along a water colour gradient now shows that coloured terrestrial organic matter controls the key process for new biomass synthesis through its effects on light attenuation, suggesting that light is the more important limiting factor.
Individuals with exactly the same genetic make-up can differ from one another in their development and resulting phenotype when the genome contains a mutation — a phenomenon called 'partial penetrance'. Exploration of the genetic and stochastic factors controlling the proportion of abnormal 'twin' spores in mutant populations of the bacterium Bacillus subtilus now reveals how mutations affecting DNA replication and cell division may act in synergy to significantly increase the penetrance of twin sporulation.
There are over 40 different simian immunodeficiency viruses (SIVs) with which African primates are naturally infected; two of these have crossed the species barrier to generate human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2). Although SIVs do not generally cause AIDS in primates, AIDS-like disease is now shown to occur in chimpanzee populations in the wild who are naturally infected with SIVcpz, a close relative of HIV-1.
Innate immunity is stimulated by non-microbial danger signals, as well as by viral or bacterial components. The threonine-phosphatase activity of the protein Eyes absent 4 (EYA4), originally identified as a co-transcription factor, is now shown to stimulate the innate immune response to the undigested DNA from apoptotic cells.
In neurotransmission, synaptic vesicles fuse with the membrane of nerve cells to release neurotransmitter content into the synaptic cleft. This process requires the assembly of several members of the SNARE protein family. Here, the X-ray structure of a neuronal SNARE complex is solved, providing insight into how these proteins assemble.
Disruption of the tumour suppressor p53, a transcriptional activator with numerous growth-suppressive targets, is a fundamental event in the development of most cancers. Here, p53 is found to have another function, independent of its role in transcription, enhancing the earliest processing step of precursors for microRNAs that regulate genes affecting cell growth.
In fasted mammals, circulating pancreatic glucagon stimulates gluconeogenesis in the liver in part through the CREB coactivator CRTC2. The production of glucose by the liver is increased in obesity, reflecting chronic increases in endoplasmic reticulum (ER) stress that promote insulin resistance. Here, CRTC2 is shown to function as a dual sensor for fasting signals and ER stress, thereby contributing to glucose homeostasis.
Nanomedicine has started to gather momentum in recent years, and cutting-edge jobs abound for those with the right training. Virginia Gewin takes a closer look.