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Current understanding holds that Klinefelter syndrome (KS) is not inherited, but arises randomly during meiosis. Whether there is any genetic basis for the origin of KS is unknown. Here, guided by our identification of some USP26 variations apparently associated with KS, we found that knockout of Usp26 in male mice resulted in the production of 41, XXY offspring. USP26 protein is localized at the XY body, and the disruption of Usp26 causes incomplete sex chromosome pairing by destabilizing TEX11. The unpaired sex chromosomes then result in XY aneuploid spermatozoa. Consistent with our mouse results, a clinical study shows that some USP26 variations increase the proportion of XY aneuploid spermatozoa in fertile men, and we identified two families with KS offspring wherein the father of the KS patient harbored a USP26-mutated haplotype, further supporting that paternal USP26 mutation can cause KS offspring production. Thus, some KS should originate from XY spermatozoa, and paternal USP26 mutations increase the risk of producing KS offspring.

In order to explore the differences of microstructure，composition and performances of different fatty acid salt superhydrophobic coatings，three kinds of fatty acid salt superhydrophobic coatings were prepared by electrodeposition on rough surface of TC4 alloy.The microstructure，chemical composition，phase and wettability of such superhydrophobic coatings were characterized and analyzed by scanning electron microscopy，X-ray diffraction，X-ray photoelectron spectroscopy，Fourier transform infrared spectroscopy and contact angle tester.The wear resistance，heat resistance and corrosion resistance of the superhydrophobic coatings were investigated by linear friction test，long time heating experiment and electrochemical experiment respectively.Results showed that fatty acid salt coatings obtained by anodic and cathodic deposition both had non-adhesion superhydrophobicity.The surface color and state of the three fatty acid salt coatings were different，but the micromorphology was all ＂cauliflower＂ cluster，and there was an obvious micro nano hierarchical structure.The wear resistance and heat resistance of the three superhydrophobic coatings were different due to different fatty acid salts.Corrosion resistance of three superhydrophobic coatings was better than that of the substrate.CSHS-Cu had the best corrosion resistance.The Jcorr of CSHS-Cu was 1/5 of that of the bare substrate，and its Rct was 25 times that of the bare substrate.

We demonstrate the synthesis of layered anisotropic semiconductor GeSe and GeSe2 nanomaterials through low temperature (∼400 °C) and atmospheric pressure chemical vapor deposition using halide based precursors. Results show that GeI2 and H2Se precursors successfully react in the gas-phase and nucleate on a variety of target substrates including sapphire, Ge, GaAs, or HOPG. Layer-by-layer growth takes place after nucleation to form layered anisotropic materials. Detailed SEM, EDS, XRD, and Raman spectroscopy measurements together with systematic CVD studies reveal that the substrate temperature, selenium partial pressure, and the substrate type ultimately dictate the resulting stoichiometry and phase of these materials. Results from this work introduce the phase control of Ge and Se based nanomaterials (GeSe and GeSe2) using halide based CVD precursors at ATM pressures and low temperatures. Overall findings also extend our fundamental understanding of their growth by making the first attempt to correlate growth parameters to resulting competing phases of Ge-Se based materials.

The public key infrastructure (PKI), as an significant component of the current Internet security infrastructure, guarantees the information transmission with the necessary authenticity, integrity, confidentiality and non-repudiation.However, the existing PKI also has shortcomings of excessive power of certification authority and difficulties in revoking and querying.Blockchain can be used to solve those problems by leveraging its advantages, such as decentralization, high transparency and flat structure.Furthermore, the ability and efficiency of the entire Internet to establish trust relationships may be improved.The transparent public key infrastructure (PKI) certification protocol based on the blockchain was proposed.The TS-PBFT algorithm was designed in the proposed protocol by adopting the threshold signature technology to the Practical Byzantine fault tolerance (PBFT) algorithm.The TS-PBFT algorithm reduced the communication overhead via reducing the communication complexity, strengthened the supervision via introducing external monitoring mechanism in the master node election of the view change protocol, and also improved the performance of the consensus mechanism via adding a batch processing mechanism.Moreover, a transparent blockchain-based PKI certification protocol was designed.The proposed protocol increased the security of certificate revocation and query, it also improved the efficiency of the certificate query by the introduction of counting bloom filters.Besides, the proposed protocol added audit function into the certificate lifecycle management.Accordingly, it can supervise the behavior of the certificate authority (CA), prompt it to improve security standards, and then achieve the purpose of limiting its authority.According to the security analysis and efficiency experiments, the proposed protocol was equipped with security properties, such as the resistance to spoofing certificate application attacks, and it achieved the best performance on TLS/SSL handshake time compared with existing PKI protocols.

Moiré superlattices enable the generation of new quantum phenomena in two-dimensional heterostructures, in which the interactions between the atomically thin layers qualitatively change the electronic band structure of the superlattice. For example, mini-Dirac points, tunable Mott insulator states and the Hofstadter butterfly pattern can emerge in different types of graphene/boron nitride moiré superlattices, whereas correlated insulating states and superconductivity have been reported in twisted bilayer graphene moiré superlattices1-12. In addition to their pronounced effects on single-particle states, moiré superlattices have recently been predicted to host excited states such as moiré exciton bands13-15. Here we report the observation of moiré superlattice exciton states in tungsten diselenide/tungsten disulfide (WSe2/WS2) heterostructures in which the layers are closely aligned. These moiré exciton states manifest as multiple emergent peaks around the original WSe2 A exciton resonance in the absorption spectra, and they exhibit gate dependences that are distinct from that of the A exciton in WSe2 monolayers and in WSe2/WS2 heterostructures with large twist angles. These phenomena can be described by a theoretical model in which the periodic moiré potential is much stronger than the exciton kinetic energy and generates multiple flat exciton minibands. The moiré exciton bands provide an attractive platform from which to explore and control excited states of matter, such as topological excitons and a correlated exciton Hubbard model, in transition-metal dichalcogenides.

The bHLH (basic helix–loop–helix) transcription factor AtCFLAP2 regulates epidermal wax accumulation, but the underlying molecular mechanism remains unknown. We obtained BnUC1mut (BnaA05g18250D homologous to AtCFLAP2) from a Brassica napus mutant with up-curling leaves (Bnuc1) and epidermal wax deficiency via map-based cloning. BnUC1mut contains a point mutation (N200S) in the conserved dimerization domain. Overexpressing BnUC1mut in ZS11 (Zhongshuang11) significantly decreased the leaf epidermal wax content, resulting in up-curled and glossy leaves. In contrast, knocking out BnUC1mut in ZS11-NIL (Zhongshuang11-near-isogenic line) restored the normal leaf phenotype (i.e., flat) and significantly increased the leaf epidermal wax content. The point mutation weakens the ability of BnUC1mut to bind to the promoters of VLCFA (very-long-chain fatty acids) synthesis-related genes, including KCS (β-ketoacyl coenzyme synthase) and LACS (long-chain acyl CoA synthetase), as well as lipid transport-related genes, including LTP (non-specific lipid transfer protein). The resulting sharp decrease in the transcription of genes affecting VLCFA biosynthesis and lipid transport disrupts the normal accumulation of leaf epidermal wax. Thus, BnUC1 influences epidermal wax formation by regulating the expression of LTP and genes associated with VLCFA biosynthesis. Our findings provide a foundation for future investigations on the mechanism mediating plant epidermal wax accumulation. [ABSTRACT FROM AUTHOR]

Selective pressures have given rise to a number of SARS-CoV-2 variants during the prolonged course of the COVID-19 pandemic. Recently evolved variants differ from ancestors in additional glycosylation within the spike protein receptor-binding domain (RBD). Details of how the acquisition of glycosylation impacts viral fitness and human adaptation are not clearly understood. Here, we dissected the role of N354-linked glycosylation, acquired by BA.2.86 sub-lineages, as a RBD conformational control element in attenuating viral infectivity. The reduced infectivity is recovered in the presence of heparin sulfate, which targets the 'N354 pocket' to ease restrictions of conformational transition resulting in a 'RBD-up' state, thereby conferring an adjustable infectivity. Furthermore, N354 glycosylation improved spike cleavage and cell–cell fusion, and in particular escaped one subset of ADCC antibodies. Together with reduced immunogenicity in hybrid immunity background, these indicate a single spike amino acid glycosylation event provides selective advantage in humans through multiple mechanisms. [ABSTRACT FROM AUTHOR]