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This paper studies the matching problem of cross-modality video data from a discrete distribution alignment view. Central to this discussion is the visible-infrared person re-identification (VI-reID), a crucial feature that bolsters surveillance systems' efficacy in monitoring individuals across diverse lighting conditions. Going beyond traditional image-to-image matching paradigms, a recent study shows that temporal information can bring richer cues to encode the pedestrian representation, improving the representation power of deep neural networks. However, this integration further complicates cross-modality data matching due to the joint processing of spatial and temporal information. This paper formulates the video data as a discrete distribution and aligns the cross-modality video representation by reducing the matching cost between the two distributions. To this end, a natural idea for aligning the videos is to reduce the divergence of distributions. Moreover, the powerful optimal transport (OT) scheme, which generates the optimal matching flows and establishes the relevance of two distributions, is also employed as a way to measure the distance of distributions. Nevertheless, we observe that endowing the OT in the advanced VI-reID feature extractor leads to a non-symmetric measurement. To mitigate this, the paper introduces a new metric, namely symmetric optimal transport (SOT), reformulating OT into a symmetric form. Thorough analyses and empirical studies affirm the superiority of the proposed SOT, which significantly outperforms the current state-of-the-art methods according to standard benchmarking evaluations. [Display omitted] • This paper formally formulates the video sequences into a discrete distribution. • This paper further provides a symmetric optimal transport (SOT) scheme. • Thorough experiments are conducted to evaluate the proposed SOT. [ABSTRACT FROM AUTHOR]

Aminoacyl-tRNA synthetases (aaRSs) are enzymes that function at the first step of translation, catalyzing the conjugation of amino acids to their cognate tRNAs for protein synthesis. While preserving this essential role, higher eukaryotic aaRSs, such as human cytoplasmic aaRSs, have developed other functions during evolution, including angiogenesis, inflammation, development, tumorigenesis, etc. These translational and nontranslational functions of aaRSs are attractive targets for developing antibacterial, antifungal, anticancer agents and for treating other human diseases. Structural characterization of aaRS functions in both categories has deepened our understanding and provided insightful platform for further structure-based drug design. The convergence of the mechanism of action, together with their divergent functions, offers a possible protocol for studying these features of aaRSs in general. To guide this objective in future, we provide here a review on the methods used in structural analysis, which may be applied to study this special group of housekeeping proteins. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu2+-chelated SPEEK membrane with high IEC is prepared. • High mechanical and dimensional stability are observed for SPEEK-Cu membrane. • Proton conductivity of SPEEK-based membranes reaches 0.074 S/cm at −25 °C. • Water states of samples at subzero temperatures are quantified via DSC analysis. • SPEEK-Cu membrane possesses a stronger anti-freezing property. Improving the proton conductivity (σ) of proton exchange membranes at low temperatures is very important for expanding their application areas. Here, sulfonated poly ether ether ketone (SPEEK) membranes were prepared with different sulfonation degrees, and its maximum ion exchange capacity is 3.15 mmol/g for 10 h at 60 °C. Highly sulfonated SPEEK membrane exhibits ultra-high water uptake and excellent proton conductivity of 0.074 S/cm at −25 °C due to its abundant −SO 3 H. Nevertheless, its high swelling ratio and low mechanical strength are not conducive to the practical application of the membrane. Luckily, by employing the chelation of Cu2+ with −SO 3 − on the SPEEK chain, Cu2+-coordinated SPEEK membranes were prepared, and they not only retain high −SO 3 H content but also possess robust mechanical properties and good dimensional stability compared to pristine SPEEK membrane. Meanwhile, the σ of the SPEEK-Cu membrane reaches 0.054 S/cm at −25 °C, and its fuel cell maximum power (W max) reaches 0.42 W/cm2 at −10 °C, demonstrating superior low-temperature performance in comparison to other reported materials. Particularly, water states in the prepared membranes are quantified by low-temperature differential scanning calorimetry. Because much more water bound to the plentiful −SO 3 H and Cu2+ inside the membrane endows it with anti-freezing performance, the decay of the σ and the W max for the SPEEK-Cu membrane is retarded at sub-zero temperatures. It is envisioned that composite membranes comprising metal ions such as Cu2+-SPEEK have a high potential for sub-zero fuel cell applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The exploration of highly efficient sunlight-assisted photocatalyst for photodegradation of organic contaminants or energy conversion is strongly encouraged. In this work, we designed a novel three-dimensional spindle-like Sv-ZIS@NMFe heterojunction made of amino functionalized NH 2 -MIL-88B(Fe) (NMFe) and ZnIn 2 S 4 nanosheets with abundant sulfur vacancies (Sv-ZIS). The structural properties of NMFe materials, such as a clearly defined system of pores and cavities, were retained by the Sv-ZIS@NMFe composites. Additionally, the incorporation of sulfur vacancies, –NH 2 functional groups, and well-matched energy level positions led to various synergistic effects that considerably enhanced internal electron transformation and migration, as well as improved adsorption performance. Consequently, under visible light irradiation, the optimized sample exhibited superior hydrogen production activity and tetracycline hydrochloride photodegradation performance. At last, density functional theory calculations was used to further elucidated the possible photoreactivity mechanism. This study demonstrates that the Sv-ZIS@NMFe heterojunction materials formed by ZnIn 2 S 4 with suitable sulfur vacancies and amino functionalized Fe-MOFs have promising applications in photocatalysis. [ABSTRACT FROM AUTHOR]

Se decorated CdS nanowires with few-layer MoSe 2 nanosheets are fabricated for efficient H 2 production. The piezoelectric field of MoSe 2 nanosheets promotes the separation of free charges. Compared with the photocatalysis, the piezo-photocatalysis yields a superior H 2 evolution rate of 59.1 mmol/h g−1 (124.9% that of photocatalysis). [Display omitted] The build-in electric field by the construction of heterojunction is one of the most promising strategies to suppress the recombination of photogenerated carriers. Here, we reported a piezo-photocatalytic system composed of Se-decorated CdS nanowires and few-layered edge-on MoSe 2 nanosheets for efficient H 2 generation by two-pot hydrothermal synthesis. The few-layered MoSe 2 exposed abundant edge sites for hydrogen evolution reaction (HER). The activity of 20-MoSe 2 /CdS 0.95 Se 0.05 (20-MS/CSS, with 20 mol% of MoSe 2 loading) nanocomposite casted a remarkable photocatalytic HER performance, with a rate of 47.3 mmol h−1 g−1. Moreover, MoSe 2 nanosheets deformed to generate the piezoelectric polarization field under magnetic stirring, which rendered efficient separation of photogenerated carriers, resulting in a piezo-photocatalytic synergistic effect. As a result, the HER of 20-MS/CSS at 900 rpm for piezo-photocatalysis was 59.1 mmol h−1 g−1, which was 1.25 times that of 20-MS/CSS for photocatalysis. Meanwhile, the photoelectrochemical measurements further visualized the piezo-photoelectric synergy. This study exposes a new way for utilizing mechanical energy to improve photocatalytic performance, and achieving high piezo-photocatalysis. [ABSTRACT FROM AUTHOR]

Few-layered MoSe 2 nanosheets were grown vertically on TiO 2 nanorods (TNr) to synthesis a direct Z-scheme heterojunction, exhibiting efficient piezocatalytic and piezo-photocatalytic performance. Moreover, a piezo-photoelectric synergistic effect of nanocomposites was also observed by current outputs. Our results highlight significance in the design of heterojunction for capturing fluid mechanical energy and improving piezo-photocatalytic synergistic effect. [Display omitted] Nano-semiconductor materials coupled with piezoelectric effect have received extensive attention due to their wide application in catalysis. In this work, few-layered MoSe 2 nanosheets were grown vertically on TiO 2 nanorods (TNr) to synthesize a direct Z-scheme heterojunction, exhibiting efficient piezocatalytic and piezo-photocatalytic performance. The MoSe 2 /TNr heterostructure exhibited superior piezoelectric degradation efficiency, successfully removing over 98% of RhB within 360 s under continuous magnetic stirring in dark. Compared with piezocatalysis, the piezo-photocatalytic system possessed higher degradation efficiency and cycle stability. Furthermore, a piezo-photoelectric synergistic effect of nanocomposites was observed by current outputs. Under stirring conditions, the current density of depleted MoSe 2 /TNr and MoSe 2 nanosheets were respectively 6.3 μA/cm2 and 5.5 μA/cm2. When light and stirring were applied, the MoSe 2 /TNr current density increased twice to 13.2 μA/cm2, while the MoSe 2 nanosheets didn't exhibit improvement. Through the direct Z-scheme heterojunction of MoSe 2 /TNr, photoexcitation and piezoelectric polarization work together to effectively replenish carriers under light irradiation, and then rapidly separate free charges through piezopotential. This work broadens the application prospects of piezocatalysis and piezo-photocatalysis in renewable energy harvesting and water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] Piezocatalysis, driven by mechanical energy and piezoelectric effect, is of great potential in addressing the environmental issues. In this work, a piezoelectric catalyst was fabricated by growing few-layer MoS 2 nanosheets onto CuS, for the piezocatalytic degradation of Rhodamine B (RhB), methylene blue (MB) and hexavalent chromium (Cr (VI)). The excellent removal efficiency of Cr (VI) and RhB can be reached 100% within 180 s, through the piezocatalysis of CuS/MoS 2 -0.6 driven by mechanical stirring in the dark. Impressively, the piezoelectric current of CuS/MoS 2 -0.6 is 48 and 35.7 times higher than that of pure CuS and MoS 2 , respectively. The significantly enhanced piezocatalytic performance can be ascribed to the formation of CuS/MoS 2 heterojunction and the piezoelectric field generated by MoS 2 nanosheets, which promotes the efficient separation of electrons and holes. This study provides insights into strategies to improve catalytic performance through utilizing mechanical energy and opens a new horizon for environmental remediation. [ABSTRACT FROM AUTHOR]

The transcription factor for immunoglobulin heavy-chain enhancer 3 (TFE3) is a member of the microphthalmia (MiT/TFE) transcription factor family. Dysregulation of TFE3 due to chromosomal abnormalities is associated with a subset of human renal cell carcinoma. Little structural information of this key transcription factor has been reported. In this study, we determined the crystal structure of the helix-loop-helix leucine zipper (HLH-Lz) domain of human TFE3 to a resolution of 2.6 Å. The HLH-Lz domain is critical for the dimerization and function of TFE3. Our structure showed that the conserved HLH region formed a four-helix bundle structure with a predominantly hydrophobic core, and the leucine zipper region contributed to the function of TFE3 by promoting dimer interaction and providing partner selectivity. Together, our results elucidated the dimerization mechanism of this important transcription factor, providing the structural basis for the development of inhibiting strategies for treating TFE3 dysregulated diseases. • TFE3 is a key transcription factor associated with a subset of human kidney cancer. • The crystal structure of the HLH-Lz domain of human TFE3 is determined. • The dimerization mechanism within HLH-Lz domain is analyzed. • We propose a possible strategy for inhibiting TFE3 activity. [ABSTRACT FROM AUTHOR]

Aminoacyl-tRNA synthetases (AARSs) catalyze the ligation of amino acids to their cognate tRNAs and therefore play an essential role in protein biosynthesis in all living cells. The KARS gene in human encodes both cytosolic and mitochondrial lysyl-tRNA synthetase (LysRS). A recent study identified a missense mutation in KARS gene (c.517T > C) that caused autosomal recessive nonsyndromic hearing loss. This mutation led to a tyrosine to histidine (YH) substitution in both cytosolic and mitochondrial LysRS proteins, and decreased their aminoacylation activity to different levels. Here, we report the crystal structure of LysRS YH mutant at a resolution of 2.5 Å. We found that the mutation did not interfere with the active center, nor did it cause any significant conformational changes in the protein. The loops involved in tetramer interface and tRNA anticodon binding site showed relatively bigger variations between the mutant and wild type proteins. Considering the differences between the cytosolic and mitochondrial tRNAlyss, we suggest that the mutation triggered subtle changes in the tRNA anticodon binding region, and the interferences were further amplified by the different D and T loops in mitochondrial tRNAlys, and led to a complete loss of the aminoacylation of mitochondrial tRNAlys. • The structure of a LysRS mutant associated with hearing loss disease was determined. • The YH mutant structure exhibited subtle differences with that of WT LysRS. • The tRNA differences may amplify the effect of YH mutation in charging mitochondrial tRNA. [ABSTRACT FROM AUTHOR]

General control nonderepressible 2 (GCN2) is a serine/threonine protein kinase, detecting a variety of stresses including amino acid starvation, reactive oxygen species, etc. in eukaryotic cells. Activation of GCN2 requires the interaction of the N-terminal RWD domain with the upstream GCN1 protein and the dimerization by the kinase domain. In this study, we determined two crystal structures of the RWD domain of human GCN2 in two different crystal packing modes. These two different crystal structures reveal a same dimer of the RWD domain, which has not been reported in previous studies. We further confirmed this novel dimer interaction in solution using gel filtration experiments, and in human embryonic kidney (HEK) 293 cells using bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation (co-IP) assays. Together, this study discovers a potential protein-protein interface on the RWD domain of human GCN2, and suggests a possible regulation between the interaction of GCN1 and the formation of GCN2 dimer. • The structure of human GCN2 RWD domain is determined with two crystal packing modes. • Crystal structures indicate that human GCN2 RWD domain formed a novel dimer. • The novel dimer of human GCN2 RWD domain is experimentally confirmed in human cells. • The novel dimer interface implies protein interaction surface during cell signaling. [ABSTRACT FROM AUTHOR]