Allotetraploid cotton is an economically important natural-fiber-producing crop worldwide. After polyploidization, Gossypium hirsutum L. evolved to produce a higher fiber yield and to better survive harsh environments than Gossypium barbadense, which produces superior-quality fibers. The global genetic and molecular bases for these interspecies divergences were unknown. Here we report high-quality de novo-assembled genomes for these two cultivated allotetraploid species with pronounced improvement in repetitive-DNA-enriched centromeric regions. Whole-genome comparative analyses revealed that speciesspecific alterations in gene expression, structural variations and expanded gene families were responsible for speciation and the evolutionary history of these species. These findings help to elucidate the evolution of cotton genomes and their domestication history. The information generated not only should enable breeders to improve fiber quality and resilience to ever-changing environmental conditions but also can be translated to other crops for better understanding of their domestication history and use in improvement.

Many genetic liver diseases present in newborns with repeated, often lethal, metabolic crises. Gene therapy using non-integrating viruses such as AAV is not optimal in this setting because the non-integrating genome is lost as developing hepatocytes proliferate1,2. We reasoned that newborn liver may be an ideal setting for AAV-mediated gene correction using CRISPR/Cas9. Here we intravenously infuse two AAVs, one expressing Cas9 and the other expressing a guide RNA and the donor DNA, into newborn mice with a partial deficiency in the urea cycle disorder enzyme, ornithine transcarbamylase (OTC). This resulted in reversion of the mutation in 10% (6.7% – 20.1%) of hepatocytes and increased survival in mice challenged with a high-protein diet, which exacerbates disease. Gene correction in adult OTC-deficient mice was lower and accompanied by larger deletions that ablated residual expression from the endogenous OTC gene, leading to diminished protein tolerance and lethal hyperammonemia on a chow diet.

The development of new promising metal-free catalysts is of great significance for the electrocatalytic hydrogen evolution reaction (HER). Herein, a rationally assembled three-dimensional (3D) architecture of 1D graphitic carbon nitride (g-C3N4) nanoribbons with 2D graphene sheets has been developed by a one-step hydrothermal method. Because of the multipathway of charge and mass transport, the hierarchically structured g-C3N4 nanoribbon-graphene hybrids lead to a high electrocatalytic ability for HER with a Tafel slope of 54 mV decade(-1), a low onset overpotential of 80 mV and overpotential of 207 mV to approach a current of 10 mA cm(-2), superior to those non-metal materials and well-developed metallic catalysts reported previously. This work presents a great advance for designing and developing highly efficient metal-free catalyst for hydrogen evolution.

A rationally designed strategy has been developed for spontaneous reduction and assembly of graphene quantum dots rich in carbonyl and carboxylic groups (ox-GQDs) onto sulfur doped graphitic carbon nitride (s-g-C 3 N 4 ) nanosheets to form unique s-g-C 3 N 4 @GQD nanohybrids by a one-step hydrothermal treatment. The fabricated architectures exhibit remarkably enhanced catalytic activity in the oxygen reduction reaction far better than the original s-g-C 3 N 4 and GQDs, which is even comparable to those of well-developed graphene and GQD-based catalysts, demonstrating the potential towards energy conversion applications.

Background Hepatitis E virus (HEV) infection has become relevant to blood transfusion practice because isolated cases of blood transmission have been reported and because HEV has been found to cause chronic infection and severe liver disease in immuno-compromised patients. Study design and Methods We tested for IgG and IgM antibodies to the hepatitis E virus (HEV) and for HEV RNA in 1939 unselected volunteer US blood donors. Subsequently, we tested the same parameters in pre- and serial post-transfusion samples from 362 prospectively followed blood recipients to assess transfusion risk. Results IgG anti-HEV seroprevalence in the total 1939 donations was 18.8%: 916 of these donations were made in 2006 at which time the seroprevalence was 21.8% and the remaining 1023 donations were in 2012 when the seroprevalence had decreased to 16.0% (p<0.01). A significant (P<0.001) stepwise increase in anti-HEV seroprevalence was seen with increasing age. Eight of 1939 donations (0.4%) tested anti-HEV IgM positive; no donation was HEV RNA positive. Two recipients had an apparent anti-HEV seroconversion, but temporal relationships and linked donor testing showed that these were not transfusion transmitted HEV infections. Conclusion No transfusion-transmitted HEV infections were observed in 362 prospectively followed blood recipients despite an anti-HEV seroprevalence among donations exceeding 16%.

Electro‐oxidative organic upgrading, as an ideal alternative to sluggish oxygen evolution reaction (OER) performance, can effectively decrease energy consumption to boost hydrogen evolution reaction (HER) performance. However, developing highly active electrocatalysts for long‐term durable organic upgrading with high selectivity at large and steady current density remains challenging. Herein, hollow NiSe nanocrystals heterogenized with carbon nanotubes (h‐NiSe/CNTs) are fabricated via a facile one‐pot approach. The highly dispersed h‐NiSe/CNTs 3D network can efficiently facilitate rapid mass/electron diffusion, thus achieving highly active and long‐term stable electrocatalysis for catalyzing methanol to value‐added formate at high and steady current density (≈345 mA cm−2) with high Faradaic efficiency (>95%). This reaction replaces sluggish OER performance to reduce the energy consumption for boosting H2 generation by six times. The critical active species and methanol activation mechanism are systematically studied using X‐ray photoelectron spectroscopy, X‐ray absorption fine structure analysis, in situ Raman, and density functional theory calculations, indicating that the non‐ignorable SeOx collaborated with in situ formed NiOOH species can synergistically modulate the d band center to achieve an optimal adsorption for methanol selective oxidation and suppress the further oxidation to CO2, thus leading to active and stable electrolysis for producing value‐added formate with high selectivity and co‐generating H2 with less energy consumption.

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Solar fuels have attracted great interest as an alternative use for solar energy. However, the challenges are high temperatures and low solar utilization for thermochemical and photochemical conversion methods, respectively. To lower the temperature in thermochemistry and increase solar energy utilization, a photothermochemical cycle (PTC) has been reported for carbon dioxide (CO2) reduction and improved by palladium-nanoparticle-loaded TiO2 (PNT). A maximum and stable carbon monoxide (CO) production of 11.05 μmol/(h g) is demonstrated using 1.0PNT, which is 8.27× the CO produced by P25 in the PTC. The PNT can enhance light utilization by a red-shifted photoresponse range and visible light absorbance of localized surface plasmon resonances (LSPRs). Photoinduced electron and hole pairs (EHPs) could be more readily separated. More available charge carriers would induce more photoinduced vacancies in the photoreaction, which serve a key role in the PTC. Additionally, Pd can promote CO2 absorbance to form Pd-CO2 – and Pd-CO2 –-VO on the defective surface in the thermal reaction. Finally, CO production can be enhanced by a photothermal coupling factor, and a reaction mechanism is proposed for the complete cycle on the basis of both theoretical calculations and experiments.