| | A deep look at synaptic dynamics
The processes behind neuronal communication have not yet been resolved in detail, but dyes, microscopy and protein analysis are beginning to fill in the gaps.
Vivien Marx | | | Outlook: Sickle-cell disease | | | | | Nature Index 2014 Global
Nick Campbell, Michelle Grayson | Introducing the index
The Nature Index allows us to track contributions by countries and by research institutions — academic, government and commercial — to selective scientific journals, independently chosen by active scientists. Analysis of this database provides insight into global hotspots for high-quality research. | Global overview
High-level results from the Nature Index show three strong regions, but also reveal a more nuanced picture. | North America
For many decades, North America has led the world with the breadth and depth of its science, and its continued dominance is apparent in the Nature Index results. | North & Western Europe
A mature scientific system helps this region to produce a strong scientific output, and support for science is high — even during an economic slump. But a heavy administrative and bureaucratic burden makes collaborations difficult. | East & Southeast Asia
China, Japan, Singapore and South Korea vividly demonstrate how significant investment in science can help to fuel national economic growth. | Central, East & South Europe
Countries in the region are pushing to adopt a broader research base, along with updated institutional organizations. But for the most part it is the physical sciences that remain strongest. | Australasia & Pacific Islands
The research landscape could not be more disparate between Australia and New Zealand. Strong Australian results are undermined by recent budget cuts, while New Zealand's output has fallen despite science spending boosts. | West Asia
Almost all countries in the region endured upheaval in 2013. Despite unsettled times the biggest research players continued to prioritize science and discovery and push for breakthroughs across the disciplines. | Central & South Asia
Asia's traditional strengths in chemistry and physical sciences continue to power scientific pursuits and collaborations in Central and South Asian countries. | Middle & South America
Scientists in Middle and South America are striving for excellence and reaching out for international collaborations, while contending with comparatively low spending levels. | Africa
Efforts to boost domestic science spending have yet to reach their goal, but are having an effect in Africa. Researchers, however, still rely heavily on funds and collaborators from richer nations. | A guide to the Nature Index
A description of the terminology and methodology used in this supplement, and a guide to the functionality available online at natureindex.com. | Nature Index tables
The world's leading countries and institutions for high–quality science, ordered by weighted fractional count (WFC) for 2013. | | | | |
| | Cell metabolism: Autophagy transcribed
Two studies find that an intracellular quality-control mechanism called autophagy is regulated by nuclear receptor proteins that govern the expression of autophagy genes. | Neurobiology: A molecular knife to dice depression
Chronic stress can cause depression in some individuals, but leaves others untouched. Engagement of a molecular pathway controlling the production of tiny RNA snippets might help to explain the difference. | Diet: Food choices for health and planet
Are you wondering what to prepare for dinner tonight? Data analyses reveal that certain food choices greatly benefit both your health and the environment. But what to do with this evidence remains a challenge to society. | Structural biology: Calcium-activated proteins visualized
The first crystal structures of bestrophin and lipid scramblase proteins cast light on how these protein families transport very different substrates across membranes, yet are both activated by calcium ions. | Global diets link environmental sustainability and human health
As incomes grow, diets change, with varying impacts on human health and the environment; here the links are examined and suggestions made for diets that both improve health and minimize environmental impacts. | β-catenin mediates stress resilience through Dicer1/microRNA regulation
Here β-catenin, which has been implicated in neurological and psychiatric diseases, including depression, is shown to mediate resilience to chronic stress in mice through induction of Dicer and microRNAs in nucleus accumbens, a key brain reward region. | X-ray structure of a calcium-activated TMEM16 lipid scramblase
The authors describe the structure of a Ca2+-activated lipid scramblase which catalyses the passive movement of lipids between the two leaflets of a lipid bilayer; the structure reveals the location of a regulatory calcium-binding site embedded within the membrane and the presence of a hydrophilic membrane-traversing cavity that is exposed to the lipid bilayer, where catalysis is likely to occur. | Metallization of vanadium dioxide driven by large phonon entropy
X-ray and neutron scattering measurements and ab initio molecular dynamics calculations show that the transition from an insulating phase to a metallic phase in vanadium dioxide is driven primarily by the entropic effects of soft anharmonic lattice vibrations, or phonons, which stabilize the metallic phase. | Overcoming the limitations of directed C–H functionalizations of heterocycles
A robust and synthetically useful method is reported that overcomes the complications associated with performing C–H functionalization reactions on heterocycles; a reactive PdX2 (X=ArCONOMe) species is generated in situ, and is directed to the appropriate C–H bond by an N-methoxy amide group. | Structural insight into autoinhibition and histone H3-induced activation of DNMT3A
A working model for histone H3-induced dynamic regulation of the de novo DNA methyltransferase. | p63+Krt5+ distal airway stem cells are essential for lung regeneration
Many patients experiencing sudden loss of lung tissue somehow undergo full recovery; here this recovery is traced to a discrete population of lung stem cells that are not only essential for lung regeneration but can be cloned and then transplanted to other mice to contribute new lung tissue. | Resolving the complexity of the human genome using single-molecule sequencing
Single-molecule, real-time DNA sequencing is used to analyse a haploid human genome (CHM1), thus closing or extending more than half of the remaining 164 euchromatic gaps in the human genome; the complete sequences of euchromatic structural variants (including inversions, complex insertions and tandem repeats) are resolved at the base-pair level, suggesting that a greater complexity of the human genome can now be accessed. | The mitotic checkpoint complex binds a second CDC20 to inhibit active APC/C
By binding and inhibiting a second CDC20 molecule, the mitotic checkpoint complex can convert a local ‘wait’ signal from unattached kinetochores to inhibit the anaphase promoting complex/cyclosome throughout the cell and avoid premature cell division. | Structure and function of a single-chain, multi-domain long-chain acyl-CoA carboxylase
A novel biotin-dependent carboxylase with a preference for long-chain acyl-CoA substrates and a unique holoenzyme architecture is described. | Transcriptional regulation of autophagy by an FXR–CREB axis
The FXR–CREB axis is identified as a key physiological switch that regulates autophagy during feeding/fasting cycles; in the fed state, the nuclear receptor FXR is shown to suppress autophagy in the liver by inhibiting autophagy-associated lipid breakdown triggered under fasting conditions by the transcriptional activator CREB. | Nutrient-sensing nuclear receptors coordinate autophagy
The nuclear receptors FXR and PPARα are shown to regulate autophagy by competing for binding to shared sites in the promoters of autophagic genes; in the fed state FXR suppresses hepatic autophagy, whereas in the fasted state PPARα is activated and reverses the normal suppression of autophagy. | | Synaptic, transcriptional and chromatin genes disrupted in autism
Whole-exome sequencing in a large autism study identifies over 100 autosomal genes that are likely to affect risk for the disorder; these genes, which show unusual evolutionary constraint against mutations, carry de novo loss-of-function mutations in over 5% of autistic subjects and many function in synaptic, transcriptional and chromatin-remodelling pathways.
Silvia De Rubeis, Xin He, Arthur P. Goldberg et al. | The contribution of de novo coding mutations to autism spectrum disorder
Family-based exome sequencing in a large autism study has identified 27 high-confidence gene targets and accurately estimates the contribution of both de novo gene-disrupting and missense mutations to the incidence of simplex autism, with target genes in affected females overlapping those in males of lower but not higher IQ; targets also overlap known targets for intellectual disability and schizophrenia, and are enriched for chromatin modifiers, FMRP-associated genes and embryonically expressed genes.
Ivan Iossifov, Brian J. O’Roak, Stephan J. Sanders et al. | Evolution of mosquito preference for humans linked to an odorant receptor
The mosquito Aedes aegypti includes two subspecies, one of which shows a preference for biting humans, whereas the other prefers to bite non-human animals; genetic analysis reveals that changes in the mosquito odorant receptor Or4 contribute to the behavioural difference—in human-preferring mosquitoes, Or4 is more highly expressed and more sensitive to sulcatone, a compound present at high levels in human odour.
Carolyn S. McBride, Felix Baier, Aman B. Omondi et al. | Clathrin regenerates synaptic vesicles from endosomes
Ultrastructural analysis of synaptic vesicle recycling reveals that clathrin is not required for the initial rapid step of vesicle recycling by ultrafast endocytosis at the plasma membrane and instead clathrin acts later at an endosome to regenerate synaptic vesicles; however, when ultrafast endocytosis does not occur (for example, in experiments at room temperature rather than physiological temperature), clathrin-mediated endocytosis does happen at the plasma membrane.
Shigeki Watanabe, Thorsten Trimbuch, Marcial Camacho-Pérez et al. | | Formic-acid-induced depolymerization of oxidized lignin to aromatics
A method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid is described that results in more than 60 wt% yield of low-molecular-mass aromatics.
Alireza Rahimi, Arne Ulbrich, Joshua J. Coon et al. | The expanding fireball of Nova Delphini 2013
High spatial resolution is needed to study the early development of a nova; here measurements of the angular size and radial velocity of Nova Delphini 2013 reveal early structures in the ejected material and a geometric distance to the nova of about 4.5 kiloparsecs from the Sun.
G. H. Schaefer, T. ten Brummelaar, D. R. Gies et al. | Experimental realization of the topological Haldane model with ultracold fermions
The Haldane model, which predicts complex topological states of matter, has been implemented by placing ultracold atoms in a tunable optical lattice that was deformed and shaken.
Gregor Jotzu, Michael Messer, Rémi Desbuquois et al. | Observation of topological transitions in interacting quantum circuits
Superconducting quantum circuits are used to directly observe and characterize topological phase transitions; this approach promises to be a powerful and general platform for characterizing topological phenomena in quantum systems.
P. Roushan, C. Neill, Yu Chen et al. | Interfacial mode coupling as the origin of the enhancement of Tc in FeSe films on SrTiO3
High-resolution angle-resolved photoemission spectroscopy reveals bosonic modes in a SrTiO3 substrate coupling to electrons in an FeSe overlayer to facilitate high-temperature superconductivity.
J. J. Lee, F. T. Schmitt, R. G. Moore et al. | Subduction-driven recycling of continental margin lithosphere
Seismic images of the subducted Atlantic slab under northeastern South America and the Alboran slab beneath the Gibraltar arc region show that subducting oceanic plates viscously entrain and remove the bottom of the continental thermal boundary layer from adjacent continental margins, driving surface tectonics and pre-conditioning the margins for further deformation.
A. Levander, M. J. Bezada, F. Niu et al. | Resolving the long-standing enigmas of a giant ornithomimosaur Deinocheirus mirificus
Two almost complete skeletons are presented for the theropod dinosaur Deinocheirus mirificus, revealing a humpbacked form with a duckbill-like skull.
Yuong-Nam Lee, Rinchen Barsbold, Philip J. Currie et al. | Comparative population genomics in animals uncovers the determinants of genetic diversity
Genome-wide DNA polymorphism analysis across 76 animal species reveals a strong effect of ecological strategies, and particularly parental investment, on species levels of genetic diversity.
J. Romiguier, P. Gayral, M. Ballenghien et al. | Radial glia require PDGFD–PDGFRβ signalling in human but not mouse neocortex
The transcriptional profiles of radial glia are compared between humans and mice during neurogenesis, implicating the growth factor PDGFD and its receptor, PDGFRβ, in human but not mouse neocortical development.
Jan H. Lui, Tomasz J. Nowakowski, Alex A. Pollen et al. | The participation of cortical amygdala in innate, odour-driven behaviour
The cortical amygdala is necessary and sufficient for processing odours that evoke aversive and attractive responses without learning.
Cory M. Root, Christine A. Denny, René Hen et al. | A three-dimensional human neural cell culture model of Alzheimer’s disease
Early-onset familial Alzheimer’s disease mutations induce both amyloid-β and tau pathologies in differentiated human neural stem cells in 3D cultures.
Se Hoon Choi, Young Hye Kim, Matthias Hebisch et al. | Piezo1 integration of vascular architecture with physiological force
The Piezo1 calcium-permeable channel is revealed to have a role in the vascular cellular response to shear stress; a mouse knockout reveals that this channel is also important for normal vascular development.
Jing Li, Bing Hou, Sarka Tumova et al. | The complete structure of the large subunit of the mammalian mitochondrial ribosome
The structure of the 39S large mitoribosome subunit is solved by cryo-electron microscopy at an impressive 3.4 Å resolution, revealing the location of 50 ribosomal proteins, the peptidyl transferase centre, the tRNAs within this active site, and the nascent peptide chain within the exit tunnel.
Basil J. Greber, Daniel Boehringer, Marc Leibundgut et al. | Structural basis for the assembly of the Sxl–Unr translation regulatory complex
The crystal structure of the RNA binding domains of Sxl and Unr with msl2 RNA shows that interwoven interactions establish cooperative assembly of the ternary complex, highlighting how binding of relatively general RNA binding domains to RNA can result in a unique and specific protein–RNA architecture.
Janosch Hennig, Cristina Militti, Grzegorz M. Popowicz et al. | | | | |
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