Πέμπτη 14 Νοεμβρίου 2019

Generation of solar spicules and subsequent atmospheric heating
Spicules are rapidly evolving fine-scale jets of magnetized plasma in the solar chromosphere. It remains unclear how these prevalent jets originate from the solar surface and what role they play in heating the solar atmosphere. Using the Goode Solar Telescope at the Big Bear Solar Observatory, we observed spicules emerging within minutes of the appearance of opposite-polarity magnetic flux around dominant-polarity magnetic field concentrations. Data from the Solar Dynamics Observatory showed subsequent...
Science: Current Issue
Thu Nov 14, 2019 20:40
News at a glance
Science: Current Issue
Thu Nov 14, 2019 20:40
Nectar--but not for parasites
Science: Current Issue
Thu Nov 14, 2019 20:40
A new form of pure carbon dazzles and attracts
Science: Current Issue
Thu Nov 14, 2019 20:40
Switching light on-chip
Science: Current Issue
Thu Nov 14, 2019 20:40
'Secret science plan is back, and critics say it's worse
Science: Current Issue
Thu Nov 14, 2019 20:40
Widely tunable compact terahertz gas lasers
The terahertz region of the electromagnetic spectrum has been the least utilized owing to inadequacies of available sources. We introduce a compact, widely frequency-tunable, extremely bright source of terahertz radiation: a gas-phase molecular laser based on rotational population inversions optically pumped by a quantum cascade laser. By identifying the essential parameters that determine the suitability of a molecule for a terahertz laser, almost any rotational transition of almost any molecular...
Science: Current Issue
Thu Nov 14, 2019 20:40
Bacterial toxin linked to severe alcoholic liver disease
Science: Current Issue
Thu Nov 14, 2019 20:40
CRISPR's unwanted anniversary
Science: Current Issue
Thu Nov 14, 2019 20:40
Drones reveal earthquake hazards hidden in the abyss
Science: Current Issue
Thu Nov 14, 2019 20:40
Neutrophils keep the peace
Science: Current Issue
Thu Nov 14, 2019 20:40
A mysterious disease is striking American beech trees
Science: Current Issue
Thu Nov 14, 2019 20:40
Predicting future terror attacks
Science: Current Issue
Thu Nov 14, 2019 20:40
Top Democrat wants big AI push
Science: Current Issue
Thu Nov 14, 2019 20:40
A broadly applicable cross-linker for aliphatic polymers containing C-H bonds
Addition of molecular cross-links to polymers increases mechanical strength and improves corrosion resistance. However, it remains challenging to install cross-links in low-functionality macromolecules in a well-controlled manner. Typically, high-energy processes are required to generate highly reactive radicals in situ, allowing only limited control over the degree and type of cross-link. We rationally designed a bis-diazirine molecule whose decomposition into carbenes under mild and controllable...
Science: Current Issue
Thu Nov 14, 2019 20:40
Life partners
Science: Current Issue
Thu Nov 14, 2019 20:40
Comment on "Eocene Fagaceae from Patagonia and Gondwanan legacy in Asian rainforests"
Wilf et al. (Research Articles, 7 June 2019, eaaw5139) claim that Castanopsis evolved in the Southern Hemisphere from where it spread to its modern distribution in Southeast Asia. However, extensive paleobotanical records of Antarctica and Australia lack evidence of any Fagaceae, and molecular patterns indicate shared biogeographic histories of Castanopsis, Castanea, Lithocarpus, and Quercus subgenus Cerris, making the southern route unlikely.
Science: Current Issue
Thu Nov 14, 2019 20:40
Arctic intruder
Science: Current Issue
Thu Nov 14, 2019 20:40
Filling the terahertz gap
Science: Current Issue
Thu Nov 14, 2019 20:40
China's key role in scaling low-carbon energy technologies
Science: Current Issue
Thu Nov 14, 2019 20:40
Change in plants as bicarbonate rises
Science: Current Issue
Thu Nov 14, 2019 20:40
Translating translation in Down syndrome
Science: Current Issue
Thu Nov 14, 2019 20:40
Corridors for biodiversity among oil palms
Science: Current Issue
Thu Nov 14, 2019 20:40
Modeling the early development of a primate embryo
Science: Current Issue
Thu Nov 14, 2019 20:40
Organelle fusion in fertility
Science: Current Issue
Thu Nov 14, 2019 20:40
Cross-linking polyethylene through carbenes
Science: Current Issue
Thu Nov 14, 2019 20:40
Activation of the ISR mediates the behavioral and neurophysiological abnormalities in Down syndrome
Down syndrome (DS) is the most common genetic cause of intellectual disability. Protein homeostasis is essential for normal brain function, but little is known about its role in DS pathophysiology. In this study, we found that the integrated stress response (ISR)—a signaling network that maintains proteostasis—was activated in the brains of DS mice and individuals with DS, reprogramming translation. Genetic and pharmacological suppression of the ISR, by inhibiting the ISR-inducing double-stranded...
Science: Current Issue
Thu Nov 14, 2019 20:40
Piling on the pressures to ecosystems
Science: Current Issue
Thu Nov 14, 2019 20:40
Highly ductile amorphous oxide at room temperature and high strain rate
Oxide glasses are an integral part of the modern world, but their usefulness can be limited by their characteristic brittleness at room temperature. We show that amorphous aluminum oxide can permanently deform without fracture at room temperature and high strain rate by a viscous creep mechanism. These thin-films can reach flow stress at room temperature and can flow plastically up to a total elongation of 100%, provided that the material is dense and free of geometrical flaws. Our study demonstrates...
Science: Current Issue
Thu Nov 14, 2019 20:40
Cellular survival over genomic perfection
Science: Current Issue
Thu Nov 14, 2019 20:40
Microbiota-derived peptide mimics drive lethal inflammatory cardiomyopathy
Myocarditis can develop into inflammatory cardiomyopathy through chronic stimulation of myosin heavy chain 6–specific T helper (TH)1 and TH17 cells. However, mechanisms governing the cardiotoxicity programming of heart-specific T cells have remained elusive. Using a mouse model of spontaneous autoimmune myocarditis, we show that progression of myocarditis to lethal heart disease depends on cardiac myosin–specific TH17 cells imprinted in the intestine by a commensal Bacteroides species peptide mimic....
Science: Current Issue
Thu Nov 14, 2019 20:40
Overcoming glass brittleness
Science: Current Issue
Thu Nov 14, 2019 20:40
New Products
Science: Current Issue
Thu Nov 14, 2019 20:40
Reuniting biogeochemistry with ecology and evolution
Science: Current Issue
Thu Nov 14, 2019 20:40
Dissecting primate early post-implantation development using long-term in vitro embryo culture
The transition from peri-implantation to gastrulation in mammals entails the specification and organization of the lineage progenitors into a body plan. Technical and ethical challenges have limited understanding of the cellular and molecular mechanisms that underlie this transition. We established a culture system that enabled the development of cynomolgus monkey embryos in vitro for up to 20 days. Cultured embryos underwent key primate developmental stages, including lineage segregation, bilaminar...
Science: Current Issue
Thu Nov 14, 2019 20:40
Microbes and genes in heart failure
Science: Current Issue
Thu Nov 14, 2019 20:40
In vitro development of monkey embryos
Science: Current Issue
Thu Nov 14, 2019 20:40
Returning the fallen
Science: Current Issue
Thu Nov 14, 2019 20:40
A glass that won't break
Science: Current Issue
Thu Nov 14, 2019 20:40
The deadly diffusion of lethal technologies
Science: Current Issue
Thu Nov 14, 2019 20:40
Cross-linking a range of alkyl polymers
Science: Current Issue
Thu Nov 14, 2019 20:40
Seabirds: Sentinels beyond the oceans
Science: Current Issue
Thu Nov 14, 2019 20:40
Many factors influence global change
Science: Current Issue
Thu Nov 14, 2019 20:40
Save horseshoe crabs and coastal ecosystems
Science: Current Issue
Thu Nov 14, 2019 20:40
Taking electrical control
Science: Current Issue
Thu Nov 14, 2019 20:40
Consider Humboldt's map as intended
Science: Current Issue
Thu Nov 14, 2019 20:40
Anti-Markovnikov hydroamination
Science: Current Issue
Thu Nov 14, 2019 20:40
Quality control in cell biology
Science: Current Issue
Thu Nov 14, 2019 20:40
Watching metal nanoparticle exsolution
Science: Current Issue
Thu Nov 14, 2019 20:40
Cellular quality control by the ubiquitin-proteasome system and autophagy
To achieve homeostasis, cells evolved dynamic and self-regulating quality control processes to adapt to new environmental conditions and to prevent prolonged damage. We discuss the importance of two major quality control systems responsible for degradation of proteins and organelles in eukaryotic cells: the ubiquitin-proteasome system (UPS) and autophagy. The UPS and autophagy form an interconnected quality control network where decision-making is self-organized on the basis of biophysical parameters...
Science: Current Issue
Thu Nov 14, 2019 20:40
VISTA is a pH-selective checkpoint
Science: Current Issue
Thu Nov 14, 2019 20:40
Cellular RNA surveillance in health and disease
The numerous quality control pathways that target defective ribonucleic acids (RNAs) for degradation play key roles in shaping mammalian transcriptomes and preventing disease. These pathways monitor most steps in the biogenesis of both noncoding RNAs (ncRNAs) and protein-coding messenger RNAs (mRNAs), degrading ncRNAs that fail to form functional complexes with one or more proteins and eliminating mRNAs that encode abnormal, potentially toxic proteins. Mutations in components of diverse RNA surveillance...
Science: Current Issue
Thu Nov 14, 2019 20:40
Structure of the RSC complex bound to the nucleosome
The RSC complex remodels chromatin structure and regulates gene transcription. We used cryo–electron microscopy to determine the structure of yeast RSC bound to the nucleosome. RSC is delineated into the adenosine triphosphatase motor, the actin-related protein module, and the substrate recruitment module (SRM). RSC binds the nucleosome mainly through the motor, with the auxiliary subunit Sfh1 engaging the H2A-H2B acidic patch to enable nucleosome ejection. SRM is organized into three substrate-binding...
Science: Current Issue
Thu Nov 14, 2019 20:40
Mitocellular communication: Shaping health and disease
Throughout the animal kingdom, mitochondria are the only organelles that retain their own genome and the transcription and translation machineries that are all essential for energy harvesting. Mitochondria have developed a complex communication network, allowing them to stay in tune with cellular needs and nuclear transcriptional programs and to alleviate mitochondrial dysfunction. Here, we review recent findings on the wide array of mechanisms that contribute to these mitocellular communication...
Science: Current Issue
Thu Nov 14, 2019 20:40
Engineering bunched Pt-Ni alloy nanocages for efficient oxygen reduction in practical fuel cells
Development of efficient and robust electrocatalysts is critical for practical fuel cells. We report one-dimensional bunched platinum-nickel (Pt-Ni) alloy nanocages with a Pt-skin structure for the oxygen reduction reaction that display high mass activity (3.52 amperes per milligram platinum) and specific activity (5.16 milliamperes per square centimeter platinum), or nearly 17 and 14 times higher as compared with a commercial platinum on carbon (Pt/C) catalyst. The catalyst exhibits high stability...
Science: Current Issue
Thu Nov 14, 2019 20:40
Magnetic fields can generate spicules
Science: Current Issue
Thu Nov 14, 2019 20:40
Nano-opto-electro-mechanical switches operated at CMOS-level voltages
Combining reprogrammable optical networks with complementary metal-oxide semiconductor (CMOS) electronics is expected to provide a platform for technological developments in on-chip integrated optoelectronics. We demonstrate how opto-electro-mechanical effects in micrometer-scale hybrid photonic-plasmonic structures enable light switching under CMOS voltages and low optical losses (0.1 decibel). Rapid (for example, tens of nanoseconds) switching is achieved by an electrostatic, nanometer-scale perturbation...
Science: Current Issue
Thu Nov 14, 2019 20:40
Tuning stress protects cognition
Science: Current Issue
Thu Nov 14, 2019 20:40
Electrical control of interlayer exciton dynamics in atomically thin heterostructures
A van der Waals heterostructure built from atomically thin semiconducting transition metal dichalcogenides (TMDs) enables the formation of excitons from electrons and holes in distinct layers, producing interlayer excitons with large binding energy and a long lifetime. By employing heterostructures of monolayer TMDs, we realize optical and electrical generation of long-lived neutral and charged interlayer excitons. We demonstrate that neutral interlayer excitons can propagate across the entire sample...
Science: Current Issue
Thu Nov 14, 2019 20:40
The architecture of the RSC complex
Science: Current Issue
Thu Nov 14, 2019 20:40
Catchment properties and the photosynthetic trait composition of freshwater plant communities
Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait...
Science: Current Issue
Thu Nov 14, 2019 20:40
Irreversible splitting of light
Science: Current Issue
Thu Nov 14, 2019 20:40
The role of multiple global change factors in driving soil functions and microbial biodiversity
Soils underpin terrestrial ecosystem functions, but they face numerous anthropogenic pressures. Despite their crucial ecological role, we know little about how soils react to more than two environmental factors at a time. Here, we show experimentally that increasing the number of simultaneous global change factors (up to 10) caused increasing directional changes in soil properties, soil processes, and microbial communities, though there was greater uncertainty in predicting the magnitude of change....
Science: Current Issue
Thu Nov 14, 2019 20:40
Peptide mimicry breaks the heart
Science: Current Issue
Thu Nov 14, 2019 20:40
Thermally condensing photons into a coherently split state of light
The quantum state of light plays a crucial role in a wide range of fields, from quantum information science to precision measurements. Whereas complex quantum states can be created for electrons in solid-state materials through mere cooling, optical manipulation and control builds on nonthermodynamic methods. Using an optical dye microcavity, we show that photon wave packets can be split through thermalization within a potential with two minima subject to tunnel coupling. At room temperature, photons...
Science: Current Issue
Thu Nov 14, 2019 20:40
Mitigating micronutrient deficiency
Science: Current Issue
Thu Nov 14, 2019 20:40
An escape into fiction
Science: Current Issue
Thu Nov 14, 2019 20:40
Change in climate withered an empire
Science: Current Issue
Thu Nov 14, 2019 20:40
Response to Comment on "Eocene Fagaceae from Patagonia and Gondwanan legacy in Asian rainforests"
Denk et al. agree that we reported the first fossil Fagaceae from the Southern Hemisphere. We appreciate their general enthusiasm for our findings, but we reject their critiques, which we find misleading and biased. The new fossils unequivocally belong to Castanopsis, and substantial evidence supports our Southern Route to Asia hypothesis.
Science: Current Issue
Thu Nov 14, 2019 20:40
Nanocage-chain fuel cell catalysts
Science: Current Issue
Thu Nov 14, 2019 20:40
In vitro culture of cynomolgus monkey embryos beyond early gastrulation
Gastrulation is a key event in embryonic development when the germ layers are specified and the basic animal body plan is established. The complexities of primate gastrulation remain a mystery because of the difficulties in accessing primate embryos at this stage. Here, we report the establishment of an in vitro culture (IVC) system that supports the continuous development of cynomolgus monkey blastocysts beyond early gastrulation up to 20 days after fertilization. The IVC embryos highly recapitulated...
Science: Current Issue
Thu Nov 14, 2019 20:40

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