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Field observations have confirmed that halide ions are widely distributed among aerosols from the marine boundary layer and on the surfaces of ice and snow in polar regions. Consequently, the coexistence of halide ions may play a more significant role in nitrate photolysis than previously thought. In this study, we simultaneously measured HONO, NO2, and NO2−in situ to gain a deeper understanding of the coexisting system, including the photogenerated nitrogen products and the effects on nitrate photolysis rates due to enhanced aqueous nitrite and HONO transfer rates by halides. The presence of halides significantly increased the photogenerated nitrogen products across various molar ratios ([X–]/[NO3−]) at pH 3.5. By eliminating oxygen flux, the transformation of the primary photogenerated products was affected, resulting in higher concentrations of N(III) as both HONO and NO2−. Experiments involving OH scavengers indicated that the attack from·OH initiated by halides leads to side reactions that enhance nitrate photolysis. Both theoretical calculations and nitrate actinometry were used to determine the photolysis rate of nitrate solutions, which together indicated that the presence of halides enhances nitrate photolysis. A newly developed model was used to determine the HONO transfer rate, finding that the presence of halides ([X–]/[NO3−] = 0.2) enhanced the evaporation of N(III) in solution by factors of 0.68, 0.95, and 1.27 for Cl−, Br−, and I−, respectively. To our knowledge, this is the first determination of halide effects on the mass transfer of HONO. The enhanced nitrate photolysis rate can be attributed to the differential surface effects of halides and parallel reactions initiated via ·OH stemming from nitrate photolysis, with varying rates leading to different quantities of nitrogenous products. Additionally, simultaneous measurements of photoproducts in both gas and condensed phases are recommended to better constrain the rate constants of NO3− photolysis.

AC-DC hybrid spot networks contain strong redundancy. It further enhances the power supply reliability of spot network systems and is helpful for the integration of distributed energy resources (DERs). However, there are few stability analysis studies of AC-DC hybrid spot networks. Focusing on the AC-DC hybrid spot network, which adopts a unified control strategy, its stability problem is studied in this article. A mathematical model of each unit is constructed for this system. Via linearization of spatial state equations, a small-signal model of the AC-DC hybrid spot network is established under different operation modes. Moreover, corresponding eigenvalue criteria are obtained, and the stability problem is analyzed by using the eigenvalue analysis method when the AC-DC hybrid spot network is subjected to a slight interference under the unified control strategy. The dominant factors of each eigenvalue are studied. Based on this approach, the influence of different control parameters on the system stability is demonstrated. Then, the control parameters are selected for control optimization. A simulation model is constructed in MATLAB/Simulink software. The eigenvalue criteria and simulation results validate the applicability of the small-signal model constructed in this article and the effectiveness of the optimization conclusions.

The photogenerated charge carrier separation and transportation of inside photocathodes can greatly influence the performance of photoelectrochemical (PEC) H2 production devices. Coupling TiO2 with p-type semiconductors to construct heterojunction structures is one of the most widely used strategies to facilitate charge separation and transportation. However, the band position of TiO2 could not perfectly match with all p-type semiconductors. Here, taking antimony selenide (Sb2Se3) as an example, a rational strategy was developed by introducing a viologen electron transfer mediator (ETM) containing polymeric film (poly-1,1′-dially-[4,4′-bipyridine]-1,1′-diium, denoted as PV2+) at the interface between Sb2Se3 and TiO2 to regulate the energy band alignment, which could inhibit the recombination of photogenerated charge carriers of interfaces. With Pt as a catalyst, the constructed Sb2Se3/PV2+/TiO2/Pt photocathode showed a superior PEC hydrogen generation activity with a photocurrent density of −18.6 mA cm−2 vs. a reversible hydrogen electrode (RHE) and a half-cell solar-to-hydrogen efficiency (HC-STH) of 1.54% at 0.17 V vs. RHE, which was much better than that of the related Sb2Se3/TiO2/Pt photocathode without PV2+ (−9.8 mA cm−2, 0.51% at 0.10 V vs. RHE).

Abstract Electrocatalytic urea synthesis is an emerging alternative technology to the traditional energy-intensive industrial urea synthesis protocol. Novel strategies are urgently needed to promote the electrocatalytic C–N coupling process and inhibit the side reactions. Here, we report a CuWO4 catalyst with native bimetallic sites that achieves a high urea production rate (98.5 ± 3.2 μg h−1 mg−1 cat) for the co-reduction of CO2 and NO3 − with a high Faradaic efficiency (70.1 ± 2.4%) at −0.2 V versus the reversible hydrogen electrode. Mechanistic studies demonstrated that the combination of stable intermediates of *NO2 and *CO increases the probability of C–N coupling and reduces the potential barrier, resulting in high Faradaic efficiency and low overpotential. This study provides a new perspective on achieving efficient urea electrosynthesis by stabilizing the key reaction intermediates, which may guide the design of other electrochemical systems for high-value C–N bond-containing chemicals.

Abstract Identification, sorting, and sequencing of individual cells directly from in situ samples have great potential for in‐depth analysis of the structure and function of microbiomes. In this work, based on an artificial intelligence (AI)‐assisted object detection model for cell phenotype screening and a cross‐interface contact method for single‐cell exporting, we developed an automatic and index‐based system called EasySort AUTO, where individual microbial cells are sorted and then packaged in a microdroplet and automatically exported in a precisely indexed, “One‐Cell‐One‐Tube” manner. The target cell is automatically identified based on an AI‐assisted object detection model and then mobilized via an optical tweezer for sorting. Then, a cross‐interface contact microfluidic printing method that we developed enables the automated transfer of cells from the chip to the tube, which leads to coupling with subsequent single‐cell culture or sequencing. The efficiency of the system for single‐cell printing is >93%. The throughput of the system for single‐cell printing is ~120 cells/h. Moreover, >80% of single cells of both yeast and Escherichia coli are culturable, suggesting the superior preservation of cell viability during sorting. Finally, AI‐assisted object detection supports automated sorting of target cells with high accuracy from mixed yeast samples, which was validated by downstream single‐cell proliferation assays. The automation, index maintenance, and vitality preservation of EasySort AUTO suggest its excellent application potential for single‐cell sorting.

For single-terminal voltage source converter (VSC)-based DC distribution networks, the characteristics of bipolar short-circuit faults are a key factor for the design of protection schemes and the selection of power electronic devices. However, the contribution of AC systems is usually ignored at the diode natural commutation and conduction stage. There is no precise mathematical analysis model for this stage, and no influence mechanism of AC system has been demonstrated from theoretical perspective. This article presents a fault analysis model of the diode natural commutation and conduction stage, focusing on the transient feeding process of VSC converter during the bipolar short-circuit fault for single-terminal VSC-based DC distribution networks. According to equivalent circuits of different transient substages, accurate mathematical state equations are established. Expressions of each electrical fault variation during different substages are provided. A precise mathematical model is constructed, which considers the contribution mechanism of AC system at this stage. Then, based on this mathematical model, the influence of the AC system on electrical fault variations is analyzed from a theoretical perspective. The analysis results show that the influence is always small under different conditions and that ignoring the contribution of AC system can still meet actual engineering needs. A simulation model is constructed using MATLAB/Simulink software. The simulation results validate the effectiveness and superiority of the analysis model.

The three-dimensional (3D) interactions between crossing shock waves and a turbulent boundary layer (CSWBLI) inside a symmetric double fin are experimentally studied using nanoparticle-based planar laser scattering, supersonic particle image velocimetry, and surface oil visualization. The possibility of controlling the separated flow generated by CSWBLI is considered by employing micro-ramp vortex generators. First, the fractal dimension, velocity profile, and logarithmic law of the incoming turbulent boundary layer at Mach number 2.8 are examined. Then, the flow structure and velocity distribution, which have seldom been presented in previous experiments, are measured in high resolution. The 3D behavior of the boundary layer after CSWBLI shows that the boundary layer becomes thicker behind the shock wave and converges toward the symmetry plane of the double fin. The converged effect contributes to the largest thickness of the boundary layer in the symmetry plane accompanied with a separation region near the wall. Introduction of seven equidistant micro-ramps upstream of the double fin is proved to suppress the separation region, where the arc-like vortices generated by the middle micro-ramps are found to be more sustainable along the streamwise direction. The micro-ramps can increase the momentum exchange between the boundary layer and the surrounding mainstream. At the same time, the momentum exchange induced by the micro-ramps decreases the flow velocity outside the converged region in comparison with the configuration without micro-ramps. The results obtained in this paper can provide an experimental insight into the 3D physical phenomena existing in the CSWBLI and its flow control.

pH was one of the important meat quality traits, which was an important factor affecting the storage/shelf life and quality of meat in meat production. In order to find a way to extend the storage/shelf life, the pH values (pH45min, pH24h, pH48h and pH72h) of the longissimus dorsi muscles in F2 individuals of 462 Texel sheep × Altay sheep were determined, genotyping was performed using Illumina Ovine SNP 600 K BeadChip and whole genome resequencing technology, a genome-wide association analysis (GWAS) was used to screen the candidate genes and molecular markers for pH values related to the quality traits of mutton, and the effects of population stratification were detected by Q–Q plots. The results showed that the pH population stratification analysis did not find significant systemic bias, and there was no obvious population stratification effect. The results of the association analysis showed that 28 SNPs significantly associated with pH reached the level of genomic significance. The candidate gene associated with pH45min was identified as the CCDC92 gene by gene annotation and a search of the literature. Candidate genes related to pH24h were KDM4C, TGFB2 and GOT2 genes. The candidate genes related to pH48h were MMP12 and MMP13 genes. The candidate genes related to pH72h were HILPDA and FAT1 genes. Further bioinformatics analyses showed 24 gene ontology terms and five signaling pathways that were significantly enriched (p ≤ 0.05). Many terms and pathways were related to cellular components, processes of protein modification, the activity of protein dimerization and hydrolase activity. These identified SNPs and genes could provide useful information about meat and the storage/shelf life of meat, thereby extending the storage/shelf life and quality of meat.

Background: The CAV family, especially CAV1 and CAV2, is significantly associated with tumor development. In this study, we aimed to explore the pathogenic and prognostic roles of CAV1 and CAV2 in head and neck squamous cell carcinoma (HNSCC) through bioinformatic analysis and verified in human tissue. Methods: We analyzed expression profiles of CAV1 and CAV2 in HNSCC and in normal tissues via data from The Cancer Genome Altas. Prognostic significance was examined by Kaplan–Meier survival curve obtained from the Xena browser together with Cox regression analysis. Co-expressed genes were uploaded to GeneMANIA and applied to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, showing interaction networks. Signaling pathways of CAV1 and CAV2 in HNSCC were analyzed by Gene Set Enrichment Analysis to elucidate potential regulatory mechanisms. Gene–drug interaction network was explored via Comparative Toxicogenomics Database. Immunohistochemistry was performed to verify theoretical results. Results: Compared with normal tissues, expression levels of CAV1 and CAV2 were remarkably higher in HNSCC (p < 0.0001), which independently implies poor OS (CAV1: HR: 1.146, p = 0.027; CAV2: HR: 1.408, p = 0.002). Co-expressed genes (PXN, ITGA3, TES, and MET) were identified and analyzed by FunRich with CAV1 and CAV2, revealing a significant correlation with focal adhesion (p < 0.001), which has a vital influence on cancer progression. GSEA also showed cellular protein catabolic process (ES = 0.42) and proteasome complex (ES = 0.72), which is a key degradation system for proteins involved in oxidatively damaging and cell cycle and transcription, closely correlated with high expression of CAV2 in HNSCC. More importantly, we found the relationship between different immune cell infiltration degrees in the immune micro-environment in HNSCC and expression levels of CAV1/CAV2 (p < 0.0001). Gene–drug interaction network was checked via CTD. Moreover, tissue microarrays verified higher expression levels of CAV1/CAV2 in HNSCC (p < 0.0001), and the high expression subgroup indicated significantly poorer clinical outcomes (p < 0.05). Conclusions: The results revealed that CAV1 and CAV2 are typically upregulated in HNSCC and might predict poor prognosis.

Background: High plasma levels of trimethylamine N-oxide (TMAO) and its precursor choline have been linked to stroke; however, their association with cerebral small vessel disease remains unclear. Here we evaluated the association of plasma levels of TMAO and choline with imaging markers of cerebral small vessel disease, including white matter hyperintensities, lacunes, and cerebral microbleeds.Methods: We performed a baseline cross-sectional analysis of a multicenter hospital-based cohort study from 2015 to 2018. The data were collected from 30 hospitals in China and included 1,098 patients with ischemic stroke/transient ischemic attack aged ≥18 years. White matter hyperintensities, lacunes, and cerebral microbleeds were evaluated with the patients' demographic, clinical, and laboratory information removed. White matter hyperintensities were rated using the Fazekas visual grading scale, while the degree of severity of the lacunes and cerebral microbleeds was defined by the number of lesions.Results: Increased TMAO levels were associated with severe white matter hyperintensities [adjusted odds ratio (aOR) for the highest vs. lowest quartile, 1.5; 95% confidence interval (CI), 1.0–2.1, p = 0.04]. High TMAO levels were more strongly associated with severe periventricular white matter hyperintensities (aOR for the highest vs. lowest quartile, 1.6; 95% CI, 1.1–2.3, p = 0.009) than deep white matter hyperintensities (aOR for the highest vs. lowest quartile, 1.3; 95% CI, 0.9–1.9, p = 0.16). No significant association was observed between TMAO and lacunes or cerebral microbleeds. Choline showed trends similar to that of TMAO in the association with cerebral small vessel disease.Conclusions: In patients with ischemic stroke or transient ischemic attack, TMAO and choline appear to be associated with white matter hyperintensities, but not with lacunes or cerebral microbleeds; TMAO and choline were associated with increased risk of a greater periventricular, rather than deep, white matter hyperintensities burden.

Water oxidation is a vital anodic reaction for renewable fuel generation via electrochemical- and photoelectrochemical-driven water splitting or CO2 reduction. Ruthenium complexes, such as Ru-bda family, have been shown as highly efficient water-oxidation catalysts (WOCs), particularly when they undergo a bimolecular O-O bond formation pathway. In this study, a novel Ru(pda)-type (pda2– =1,10-phenanthroline-2,9-dicarboxylate) molecular WOC with 4-vinylpyridine axial ligands was immobilized on the glassy carbon electrode surface by electrochemical polymerization. Electrochemical kinetic studies revealed that this homocoupling polymer catalyzes water oxidation through a bimolecular radical coupling pathway, where interaction between two Ru(pda)–oxyl moieties (I2M) forms the O-O bond. The calculated barrier of the I2M pathway by density-functional theory (DFT) is significantly lower than the barrier of a water nucleophilic attack (WNA) pathway. By using this polymerization strategy, the Ru centers are brought closer in the distance, and the O-O bond formation pathway by the Ru (pda) catalyst is switched from WNA in a homogeneous molecular catalytic system to I2M in the polymerized film, providing some deep insights into the importance of third coordination sphere engineering of the water oxidation catalyst.

Objective: This study aimed to investigate whether there exist the limits of finger tapping frequency in the peripheral nerve injury detection in upper limb, and the effects of rehabilitation treatment on upper limb with peripheral nerve injury through finger tapping.Methods: Here, 54 patients with peripheral nerve injury in upper limb were selected. We conducted finger tapping frequency test and Lind-mark hand function assessment score on the 54 subjects, and recorded the data 2-week before and after rehabilitation treatment.Results: Finger tapping frequency and Lind-mark hand function assessment score have a high positive correlation regardless of the side of upper limb with peripheral nerve injury before and after the rehabilitation treatment. Finger tapping frequency of the right affected hand after treatment is significantly higher than that of before treatment (male: P < 0.05; female: P < 0.01), while finger tapping frequency of the left affected hand after treatment shows no significant difference compared to before treatment. Meanwhile, finger tapping frequency of the female subjects' unaffected hand after treatment is significantly higher than before treatment (left: P < 0.01; right: P < 0.05), however, this was not observed in male subjects. Based on data analysis, there is a high-correlation between finger tapping frequency and Lind-mark score of the patients' affected hand with brachial plexus nerve injury. A trend of the patients' affected hand with radial nerve injury is similar with brachial plexus nerve injury.Conclusion: Compared with Lind-mark score, finger tapping frequency outperformed in the aspect of speed of neural impulse conduction in patients with peripheral nerve damage.

Background: Mild cognitive impairment (MCI) is a brain disease with both anatomical and functional alterations. There is clear evidence that individuals that are diagnosed with MCI have a high risk to develop dementia in the next 2–5 years compared to an age-matched population with a non-MCI diagnosis. The present study aimed to investigate whether the finger tapping frequency of patients with MCI was different from that of healthy individuals without MCI, and whether Tai Chi, a traditional Chinese movement discipline, could improve the finger tapping frequency of MCI patients.Methods: The study population consisted of subjects of ≥50 years of age. Group one included 40 subjects without exercise habits from communities of Yangpu District in Shanghai, and group two included 60 subjects from a Tai Chi class in Shanghai Elderly University of Huangpu District. The Montreal Cognitive Assessment (MoCA) and a finger tapping test were conducted to assess the finger tapping frequency of all subjects.Results: The MoCA score of MCI subjects was significantly lower compared to subjects without MCI (P < 0.01), and was not influenced by age, weight, or height. The finger tapping frequency of MCI subjects’ left hands was significantly lower compared to that of healthy subjects without MCI (P < 0.01), and a similar trend was observed for the subjects’ right hand. The MoCA score of MCI subjects in the Tai Chi class was significantly lower than that of healthy subjects without MCI (P < 0.01), which was not influenced by age, weight or height. The finger tapping frequency of MCI subjects’ right hands was lower compared to that of healthy subjects in the Tai Chi class without MCI (P < 0.05), but no significant difference regarding the finger tapping frequency of the left hand was observed.Conclusion: These findings suggested that finger tapping frequency of MCI subjects was significantly lower compared to normal subjects without MCI, and long-term Tai Chi exercise could reduce this significant difference. Moreover, there was no significant difference between groups for the subjects’ non-dominant (left) hand.

The photogenerated charge carrier separation and transportation of inside photocathodes can greatly influence the performance of photoelectrochemical (PEC) H2 production devices. Coupling TiO2 with p-type semiconductors to construct heterojunction structures is one of the most widely used strategies to facilitate charge separation and transportation. However, the band position of TiO2 could not perfectly match with all p-type semiconductors. Here, taking antimony selenide (Sb2 Se3) as an example, a rational strategy was developed by introducing a viologen electron transfer mediator (ETM) containing polymeric film (poly-1,1 ′ -dially-[4,4 ′ -bipyridine]-1,1 ′ -diium, denoted as PV2 +) at the interface between Sb2 Se3 and TiO2 to regulate the energy band alignment, which could inhibit the recombination of photogenerated charge carriers of interfaces. With Pt as a catalyst, the constructed Sb2 Se3/PV2 +/TiO2/Pt photocathode showed a superior PEC hydrogen generation activity with a photocurrent density of - 18.6 mA cm-2 vs. a reversible hydrogen electrode (RHE) and a half-cell solar-to-hydrogen efficiency (HC-STH) of 1.54% at 0.17 V vs. RHE, which was much better than that of the related Sb2 Se3/TiO2/Pt photocathode without PV2 + (-9.8 mA cm-2, 0.51% at 0.10 V vs. RHE). [ABSTRACT FROM AUTHOR]

Bone is a tissue that is active throughout the lifespan, and its physiological activities, such as growth, development, absorption, and formation, are always ongoing. All types of stimulation that occur in sports play an important role in regulating the physiological activities of bone. Here, we track the latest research progress locally and abroad, summarize the recent, relevant research results, and systematically summarize the effects of different types of exercise on bone mass, bone strength and bone metabolism. We found that different types of exercise have different effects on bone health due to their unique technical characteristics. Oxidative stress is an important mechanism mediating the exercise regulation of bone homeostasis. Excessive high-intensity exercise does not benefit bone health but induces a high level of oxidative stress in the body, which has a negative impact on bone tissue. Regular moderate exercise can improve the body's antioxidant defense ability, inhibit an excessive oxidative stress response, promote the positive balance of bone metabolism, delay age-related bone loss and deterioration of bone microstructures and have a prevention and treatment effect on osteoporosis caused by many factors. Based on the above findings, we provide evidence for the role of exercise in the prevention and treatment of bone diseases. This study provides a systematic basis for clinicians and professionals to reasonably formulate exercise prescriptions and provides exercise guidance for patients and the general public. This study also provides a reference for follow-up research. [ABSTRACT FROM AUTHOR]