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Πέμπτη 6 Αυγούστου 2020

 Emergent helical texture of electric dipoles

Long-range ordering of magnetic dipoles in bulk materials gives rise to a broad range of magnetic structures, from simple collinear ferromagnets and antiferromagnets, to complex magnetic helicoidal textures stabilized by competing exchange interactions. In contrast, dipolar order in dielectric crystals is typically limited to parallel (ferroelectric) and antiparallel (antiferroelectric) collinear alignments of electric dipoles. Here, we report an observation of incommensurate helical ordering of...
Science: Current Issue
Thu Aug 06, 2020 20:40
Short path to a complex ring
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Thu Aug 06, 2020 20:40
Productivity in a pandemic
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Thu Aug 06, 2020 20:40
Sites of vulnerability in SARS-CoV-2
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Thu Aug 06, 2020 20:40
News at a glance
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Thu Aug 06, 2020 20:40
Depression as a lab mate
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Thu Aug 06, 2020 20:40
Why infection poses a special risk to pregnant women
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Thu Aug 06, 2020 20:40
Impaired type I interferon activity and inflammatory responses in severe COVID-19 patients
Coronavirus disease 2019 (COVID-19) is characterized by distinct patterns of disease progression that suggest diverse host immune responses. We performed an integrated immune analysis on a cohort of 50 COVID-19 patients with various disease severity. A distinct phenotype was observed in severe and critical patients, consisting of a highly impaired interferon (IFN) type I response (characterized by no IFN-β and low IFN-α production and activity), which was associated with a persistent blood viral...
Science: Current Issue
Thu Aug 06, 2020 20:40
COVID-19 unlikely to cause birth defects, but doctors await fall births
Science: Current Issue
Thu Aug 06, 2020 20:40
Stabilizing monolayer nitrides with silicon
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Thu Aug 06, 2020 20:40
Fast, cheap tests could enable safer reopening
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Thu Aug 06, 2020 20:40
Modeling coronavirus infection
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Thu Aug 06, 2020 20:40
Pandemic hits scientist parents hard
Science: Current Issue
Thu Aug 06, 2020 20:40
Structural insight into precursor ribosomal RNA processing by ribonuclease MRP
Ribonuclease (RNase) MRP is a conserved eukaryotic ribonucleoprotein complex that plays essential roles in precursor ribosomal RNA (pre-rRNA) processing and cell cycle regulation. In contrast to RNase P, which selectively cleaves transfer RNA–like substrates, it has remained a mystery how RNase MRP recognizes its diverse substrates. To address this question, we determined cryo–electron microscopy structures of Saccharomyces cerevisiae RNase MRP alone and in complex with a fragment of pre-rRNA. These...
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Thu Aug 06, 2020 20:40
Abortion opponents dominate Trump's fetal tissue review board
Science: Current Issue
Thu Aug 06, 2020 20:40
Cell-cell adhesion in plant grafting is facilitated by {beta}-1,4-glucanases
Plant grafting is conducted for fruit and vegetable propagation, whereby a piece of living tissue is attached to another through cell-cell adhesion. However, graft compatibility limits combinations to closely related species, and the mechanism is poorly understood. We found that Nicotiana is capable of graft adhesion with a diverse range of angiosperms. Comparative transcriptomic analyses on graft combinations indicated that a subclade of β-1,4-glucanases secreted into the extracellular region facilitates...
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Thu Aug 06, 2020 20:40
Trump directive on state counts said to threaten rigor of census
Science: Current Issue
Thu Aug 06, 2020 20:40
The proteasome controls ESCRT-III-mediated cell division in an archaeon
Sulfolobus acidocaldarius is the closest experimentally tractable archaeal relative of eukaryotes and, despite lacking obvious cyclin-dependent kinase and cyclin homologs, has an ordered eukaryote-like cell cycle with distinct phases of DNA replication and division. Here, in exploring the mechanism of cell division in S. acidocaldarius, we identify a role for the archaeal proteasome in regulating the transition from the end of one cell cycle to the beginning of the next. Further, we identify the...
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Thu Aug 06, 2020 20:40
Siberia's 'gateway to the underworld hit by heat wave
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Thu Aug 06, 2020 20:40
Seeking broad protection
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Thu Aug 06, 2020 20:40
Deforestation in the Brazilian Amazon is still rising sharply
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Thu Aug 06, 2020 20:40
The magnetic field in the Sun's corona
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Thu Aug 06, 2020 20:40
The long haul
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Thu Aug 06, 2020 20:40
Drug targets found in translation
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Thu Aug 06, 2020 20:40
Chimeric plants--the best of both worlds
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Thu Aug 06, 2020 20:40
Down the line
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Thu Aug 06, 2020 20:40
Specificity in legume nodule symbiosis
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Thu Aug 06, 2020 20:40
Potent neutralizing antibodies from COVID-19 patients define multiple targets of vulnerability
The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a large impact on global health, travel, and economy. Therefore, preventative and therapeutic measures are urgently needed. Here, we isolated monoclonal antibodies from three convalescent coronavirus disease 2019 (COVID-19) patients using a SARS-CoV-2 stabilized prefusion spike protein. These antibodies had low levels of somatic hypermutation and showed a strong enrichment in VH1-69, VH3-30-3, and VH1-24 gene...
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Thu Aug 06, 2020 20:40
Opening the floodgates at Fukushima
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Thu Aug 06, 2020 20:40
Chemical vapor deposition of layered two-dimensional MoSi2N4 materials
Identifying two-dimensional layered materials in the monolayer limit has led to discoveries of numerous new phenomena and unusual properties. We introduced elemental silicon during chemical vapor deposition growth of nonlayered molybdenum nitride to passivate its surface, which enabled the growth of centimeter-scale monolayer films of MoSi2N4. This monolayer was built up by septuple atomic layers of N-Si-N-Mo-N-Si-N, which can be viewed as a MoN2 layer sandwiched between two Si-N bilayers. This material...
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Thu Aug 06, 2020 20:40
Unifying the synthesis of nucleoside analogs
Science: Current Issue
Thu Aug 06, 2020 20:40
How hair deforms steel
Steels for sharp edges or tools typically have martensitic microstructures, high carbide contents, and various coatings to exhibit high hardness and wear resistance. Yet they become practically unusable upon cutting much softer materials such as human hair, cheese, or potatoes. Despite this being an everyday observation, the underlying physical micromechanisms are poorly understood because of the structural complexity of the interacting materials and the complex boundary conditions of their co-deformation....
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Thu Aug 06, 2020 20:40
COVID-19 in Africa: Dampening the storm?
Science: Current Issue
Thu Aug 06, 2020 20:40
Type III interferons disrupt the lung epithelial barrier upon viral recognition
Viral infections of the lower respiratory tract are a leading cause of mortality. Mounting evidence indicates that most severe cases are characterized by aberrant immune responses and do not depend on viral burden. In this study, we assessed how type III interferons (IFN-) contribute to the pathogenesis induced by RNA viruses. We report that IFN- is present in the lower, but not upper, airways of patients with coronavirus disease 2019 (COVID-19). In mice, we demonstrate that IFN- produced by lung...
Science: Current Issue
Thu Aug 06, 2020 20:40
Interferon responses in viral pneumonias
Science: Current Issue
Thu Aug 06, 2020 20:40
Broad neutralization of SARS-related viruses by human monoclonal antibodies
Broadly protective vaccines against known and preemergent human coronaviruses (HCoVs) are urgently needed. To gain a deeper understanding of cross-neutralizing antibody responses, we mined the memory B cell repertoire of a convalescent severe acute respiratory syndrome (SARS) donor and identified 200 SARS coronavirus 2 (SARS-CoV-2) binding antibodies that target multiple conserved sites on the spike (S) protein. A large proportion of the non-neutralizing antibodies display high levels of somatic...
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Thu Aug 06, 2020 20:40
John D. Gearhart (1943-2020)
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Thu Aug 06, 2020 20:40
Erratum for the Report "Activation of methane: A selective industrial route to methanesulfonic acid" (previously titled "Activation of methane to CH3+: A selective industrial route to methanesulfonic acid") by C. Diaz-Urrutia and T. Ott
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Thu Aug 06, 2020 20:40
Engage with animal welfare in conservation
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Thu Aug 06, 2020 20:40
Hitting SARS-CoV-2 in a new spot
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Thu Aug 06, 2020 20:40
The unlikely role of dinosaurs in the diversity discourse
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Thu Aug 06, 2020 20:40
Grafting success by cell wall remodeling
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Thu Aug 06, 2020 20:40
Saving species, one roll at a time
Science: Current Issue
Thu Aug 06, 2020 20:40
Mapping metal sequences in MOFs
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Thu Aug 06, 2020 20:40
The Amazon's road to deforestation
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Thu Aug 06, 2020 20:40
Interferons interfere with lung repair
Science: Current Issue
Thu Aug 06, 2020 20:40
Smoke pollution's impacts in Amazonia
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Thu Aug 06, 2020 20:40
The second way to anticommensal IgA
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Thu Aug 06, 2020 20:40
Funding quandary
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Thu Aug 06, 2020 20:40
Breaking and exiting
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Thu Aug 06, 2020 20:40
Investors can help rein in Amazon deforestation
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Thu Aug 06, 2020 20:40
Folding for self-protection
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Thu Aug 06, 2020 20:40
Expanding the brain researcher's toolkit
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Thu Aug 06, 2020 20:40
Union membership reduces racism
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Thu Aug 06, 2020 20:40
Seeing the sound
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Thu Aug 06, 2020 20:40
Polarized perovskite luminescence
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Thu Aug 06, 2020 20:40
A hair-splitting way to get dull
Science: Current Issue
Thu Aug 06, 2020 20:40
A neutralizing human antibody binds to the N-terminal domain of the Spike protein of SARS-CoV-2
Developing therapeutics against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be guided by the distribution of epitopes, not only on the receptor binding domain (RBD) of the Spike (S) protein but also across the full Spike (S) protein. We isolated and characterized monoclonal antibodies (mAbs) from 10 convalescent COVID-19 patients. Three mAbs showed neutralizing activities against authentic SARS-CoV-2. One mAb, named 4A8, exhibits high neutralization potency against both authentic...
Science: Current Issue
Thu Aug 06, 2020 20:40
Adapted to the task at hand
Science: Current Issue
Thu Aug 06, 2020 20:40
Ligand-recognizing motifs in plant LysM receptors are major determinants of specificity
Plants evolved lysine motif (LysM) receptors to recognize and parse microbial elicitors and drive intracellular signaling to limit or facilitate microbial colonization. We investigated how chitin and nodulation (Nod) factor receptors of Lotus japonicus initiate differential signaling of immunity or root nodule symbiosis. Two motifs in the LysM1 domains of these receptors determine specific recognition of ligands and discriminate between their in planta functions. These motifs define the ligand-binding...
Science: Current Issue
Thu Aug 06, 2020 20:40
A helix of dipoles
Science: Current Issue
Thu Aug 06, 2020 20:40
Sequencing of metals in multivariate metal-organic frameworks
We mapped the metal sequences within crystals of metal-oxide rods in multivariate metal-organic framework–74 containing mixed combinations of cobalt (Co), cadmium (Cd), lead (Pb), and manganese (Mn). Atom probe tomography of these crystals revealed the presence of heterogeneous spatial sequences of metal ions that we describe, depending on the metal and synthesis temperature used, as random (Co, Cd, 120°C), short duplicates (Co, Cd, 85°C), long duplicates (Co, Pb, 85°C), and insertions (Co, Mn, 85°C)....
Science: Current Issue
Thu Aug 06, 2020 20:40
Air pollution epidemic
Science: Current Issue
Thu Aug 06, 2020 20:40
A new wrinkle on liquid sheets: Turning the mechanism of viscous bubble collapse upside down
Viscous bubbles are prevalent in both natural and industrial settings. Their rupture and collapse may be accompanied by features typically associated with elastic sheets, including the development of radial wrinkles. Previous investigators concluded that the film weight is responsible for both the film collapse and wrinkling instability. Conversely, we show here experimentally that gravity plays a negligible role: The same collapse and wrinkling arise independently of the bubble’s orientation. We...
Science: Current Issue
Thu Aug 06, 2020 20:40
Switching perception of friend and foe
Science: Current Issue
Thu Aug 06, 2020 20:40
Global maps of the magnetic field in the solar corona
Understanding many physical processes in the solar atmosphere requires determination of the magnetic field in each atmospheric layer. However, direct measurements of the magnetic field in the Sun’s corona are difficult to obtain. Using observations with the Coronal Multi-channel Polarimeter, we have determined the spatial distribution of the plasma density in the corona and the phase speed of the prevailing transverse magnetohydrodynamic waves within the plasma. We combined these measurements to...
Science: Current Issue
Thu Aug 06, 2020 20:40
Slower-motion bubble collapse
Science: Current Issue
Thu Aug 06, 2020 20:40
Unexpected air pollution with marked emission reductions during the COVID-19 outbreak in China
The absence of motor vehicle traffic and suspended manufacturing during the coronavirus disease 2019 (COVID-19) pandemic in China enabled assessment of the efficiency of air pollution mitigation. Up to 90% reduction of certain emissions during the city-lockdown period can be identified from satellite and ground-based observations. Unexpectedly, extreme particulate matter levels simultaneously occurred in northern China. Our synergistic observation analyses and model simulations show that anomalously...
Science: Current Issue
Thu Aug 06, 2020 20:40
Panning for diagnostic gold
Science: Current Issue
Thu Aug 06, 2020 20:40
Type I and III interferons disrupt lung epithelial repair during recovery from viral infection
Excessive cytokine signaling frequently exacerbates lung tissue damage during respiratory viral infection. Type I (IFN-α and IFN-β) and III (IFN-) interferons are host-produced antiviral cytokines. Prolonged IFN-α and IFN-β responses can lead to harmful proinflammatory effects, whereas IFN- mainly signals in epithelia, thereby inducing localized antiviral immunity. In this work, we show that IFN signaling interferes with lung repair during influenza recovery in mice, with IFN- driving these effects...
Science: Current Issue
Thu Aug 06, 2020 20:40
Lower power limit to subseafloor life
Science: Current Issue
Thu Aug 06, 2020 20:40
A short de novo synthesis of nucleoside analogs
Nucleoside analogs are commonly used in the treatment of cancer and viral infections. Their syntheses benefit from decades of research but are often protracted, unamenable to diversification, and reliant on a limited pool of chiral carbohydrate starting materials. We present a process for rapidly constructing nucleoside analogs from simple achiral materials. Using only proline catalysis, heteroaryl-substituted acetaldehydes are fluorinated and then directly engaged in enantioselective aldol reactions...
Science: Current Issue
Thu Aug 06, 2020 20:40
A different picture in Africa
Science: Current Issue
Thu Aug 06, 2020 20:40
Building bridges
Science: Current Issue
Thu Aug 06, 2020 20:40
Proteasomal control of division in Archaea
Science: Current Issue
Thu Aug 06, 2020 20:40
Response to Comment on "Activation of methane to CH3+: A selective industrial route to methanesulfonic acid"
Roytman and Singleton argue that our proposed electrophilic mechanism for the sulfonation of methane in superacid conditions is "not plausible." We clarify certain terms that might have caused misinterpretation of our proposed mechanism and supplement the discussion. We reaffirm that an electrophilic mechanism may be operative under our reaction conditions.
Science: Current Issue
Thu Aug 06, 2020 20:40

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