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Developing durable electrocatalysts with high performance for hydrogen evolution reaction (HER) in acid conditions is of prime challenge for hydrogen production. Durability is of important prerequisite for catalyst application. Herein, this work constructs the Co‐doped WO3 loaded with Pt nanoparticles under ammonia treatment (Pt/N‐CoWO3) with the Pt‐N/O‐W interaction, which shows excellent activity and stability for acidic hydrogen production at industrial current density. The electronic structure of Pt species is modulated with enhanced Pt‐N/O bonding by Co doping, hence reinforcing the metal‐support interaction, and greatly enhancing the stability of the catalyst under high current density in acidic media. The resultant Pt/N‐CoWO3 catalyst exhibits the overpotentials of only 94 and 108 mV at high current densities of 1 and 2 A cm−2, respectively. More impressively, Pt/N‐CoWO3 delivers a record operation for acid electrocatalytic hydrogen evolution over 2000 h at 1 A cm−2, denoting its potential for catalyst applications at the industrial current density. This work opens a new avenue for developing Pt‐loading acidic HER catalysts for long‐term operation at ampere‐level current densities in acid conditions. [ABSTRACT FROM AUTHOR]

Desvenlafaxine succinate is a selective serotonin–norepinephrine reuptake inhibitor for the treatment of major depressive disorder. The pharmacokinetic profile of desvenlafaxine succinate at the clinically recommended dose of 50 mg in Chinese healthy subjects has been reported rarely. The objective of this study was to evaluate the pharmacokinetics and bioequivalence of desvenlafaxine succinate in Chinese healthy subjects. A single‐dose, open‐label, randomized, two‐way crossover study with a 7‐day washout period was conducted. A total of 88 individuals were incorporated to show bioequivalence of a generic and a reference drug, with 48 individuals in the fasting state and 40 receiving a high‐fat diet. Finally, 46 and 38 individuals completed the fasting and the fed study, respectively. The 90% confidence intervals of the adjusted geometric mean ratios for maximum plasma concentration, area under the concentration–time curve from time zero to the last measurable concentration, and area under the concentration–time curve from time zero to infinity all fell in the bioequivalent interval of 80%–125% in both the fasting and fed states. A total of 33 adverse events were reported, and all were mild or moderate in severity. In summary, the generic and reference formulations were bioequivalent, with no observable safety differences in the fasting/fed state. [ABSTRACT FROM AUTHOR]

Land degradation has become an urgent environmental issue globally. The complexity of land degradation hinders its quantification and monitoring, which is needed to realize the sustainable development of land resources. This study constructed a comprehensive index—land degradation status index (LDSI), which integrates in fractional vegetation cover (FVC), net primary productivity (NPP), albedo, and modified temperature vegetation drought index (MTVDI) based on spatial principal component analysis (SPCA). Land degradation was then identified by the dynamics of land degradation status during 2001–2018. This study investigated the spatio‐temporal process and driving mechanism of land degradation in Northern China. The result indicates that: (1) LDSI had a better monitoring performance compared with normalized difference vegetation index (NDVI), (2) although some degraded land had been effectively rehabilitated (17.11%), a highly clustered spatial distribution of land degradation status remained, challenging to break, (3) localized land degradation had expanded (1.063%), mainly in semiarid (0.481%), dry sub‐humid (0.289%), and humid (0.187%) regions, and (4) differences in climate, environmental backgrounds, and human activities were driven land degradation status and process. This study also assessed the effectiveness of ecological projects implemented by the Chinese government. The in‐depth understanding of the change regularity and influencing mechanism in land degradation status and process can provide a scientific basis for formulating ecological policies based on local conditions. [ABSTRACT FROM AUTHOR]

The problem of grassland degradation induced by livestock production at the expense of local grasses has become a serious ecological problem worldwide. To maintain livestock production and sustainable grassland development, the extent and intensity of grassland utilization needs to be better understood. In this study, a model was developed to monitor the intensity of grazing in a typical grazing area (Tibet Selinco basin) of the Qinghai‐Tibet Plateau. Combining the number of livestock at the township scale with their matching livestock habitat area and location, the biomass consumed by livestock was assigned to a productivity supply map (NPP) using a mathematical iterative algorithm from the perspective of different foraging habits of different livestock. The objective was to accurately measure the overall grazing pressure on the pasture as well as to estimate livestock pasture utilization. The model confirmed distinct spatial differences in the intensity of grassland utilization in the Tibet Selinco basin, in which the overall intensity was significantly low except in the southwestern region. The overall grazing area was found to be 150,000 km2, of which moderate grazing area occupied 130,000 km2 and overgrazing area occupied 20,000 km2, accounting for 87% and 13% of the total grazing area, respectively. The proposed model can quantify human activities spatially and provide a reliable and accurate scientific basis for livestock production development and ecological environment management. [ABSTRACT FROM AUTHOR]

The bioequivalence of the reference and test linagliptin formulations was assessed in healthy Chinese subjects under fasting and fed conditions. The study was designed as a single‐dose, randomized, open‐label, 2‐period crossover study with a 35‐day washout period between 2 administrations. Forty‐eight healthy subjects received 5 mg of test and reference linagliptin formulation orally under fasting condition. The geometric mean of the maximum observed linagliptin concentration (Cmax) for the test formulation was 4.9 ng/mL (reference, 5.0 ng/mL), the area under the plasma concentration–time curve from 0 to 72 hours (AUC0‐72) was 154.7 ng · h/mL (reference, 157.4 ng · h/mL). Thirty‐six subjects received 5 mg of test and reference linagliptin formulation orally under fed conditions. The geometric mean of Cmax for the test linagliptin formulation was 2.8 ng/mL (reference, 2.8 ng/mL), AUC0‐72 was 133.5 ng · h/mL (reference, 136.6 ng · h/mL). The 90%CIs for the test/reference ratio for Cmax and AUC0‐72 met the bioequivalence criteria (80%‐125%). The test and reference formulations of linagliptin were well tolerated and bioequivalent under fasting and fed conditions. [ABSTRACT FROM AUTHOR]

Photostability is one of the most essential properties for evaluating photoelectrochemical (PEC) water splitting performance on semiconductors. Herein, the oxygen‐deficiency conditions are applied to tune and activate BiVO4 photoanodes with a class of oxygen vacancies across the whole bulk material, and regulate the electronic occupancy of these states upon the charge carrier processes that determine PEC water oxidation activity. Through the experimental results and nonadiabatic molecular dynamics with time‐domain density functional theory calculations, the charge carrier lifetime can be influenced by the oxygen vacancies concentration on BiVO4, and the semiconductor can be flexibly photoactivated under oxygen‐sufficient and deficient atmospheres for enhancing the charge carrier density and photovoltage. The PEC performance of BiVO4 is further boosted by Pt doping, which exhibits a record photocurrent density of 5.45 mA cm–2 at 1.23 VRHE with solar conversion efficiency of 2.1% at 0.65 VRHE. The Pt can prevent the unnecessory charge recombination on the defected BiVO4, which also enhances the majority charge carrier density, resulting in one of the best charge separation efficiencies, close to 100%, among the steady‐state PEC performance for BiVO4. More importantly, the resulting Pt:BiVO4 presents long‐term stability over 50 h at 0.8 VRHE. [ABSTRACT FROM AUTHOR]

A photocharge/discharge strategy is proposed to initiate the WO3 photoelectrode and suppress the main charge recombination, which remarkably improves the photoelectrochemical (PEC) performance. The photocharged WO3 surrounded by a 8–10 nm overlayer and oxygen vacancies could be operated more than 25 cycles with 50 h durability without significant decay on PEC activity. A photocharged WO3/CuO photoanode exhibits an outstanding photocurrent of 3.2 mA cm−2 at 1.23 VRHE with a low onset potential of 0.6 VRHE, which is one of the best performances of p‐n heterojunction structure. Using nonadiabatic molecular dynamics combined with time‐domain DFT, we clarify the prolonged charge carrier lifetime of photocharged WO3, as well as how electronic systems of photocharged WO3/CuO semiconductors enable the effective photoinduced electrons transfer from WO3 into CuO. This work provides a feasible route to address excessive defects existed in photoelectrodes without causing extra recombination. [ABSTRACT FROM AUTHOR]

Aim: To explore how auditory and speech function developed post-cochlear implantation (pCI) in prelingually deaf children with white matter lesions (WML).Method: Patients (41 males, 29 females; mean age at implantation 2y 11mo [SD 7.5mo], range 1y 8mo-5y) were divided into the following groups according to preoperative brain magnetic resonance imaging evaluation: mild WML, moderate WML, severe WML, and control. We assessed auditory and speech performance at baseline, 6 months, 12 months, and 24 months pCI. As well as auditory event-related potentials, topographic maps and electroencephalography source imaging were recorded and analysed at 24 months pCI.Results: For children with WML (any level), postoperative auditory or speech performance at 6 months was significantly below that of control participants. After stratification, auditory and speech performance was highly related to WML grading. Auditory or speech performance in mild WML or control groups was comparatively better than the moderate WML and severe WML groups. The recovery rate of speech performance fell behind that of the auditory perception. With the increasing severity of WML, N1 amplitude was significantly smaller with a consistent presentation in the topographic map, which was similar in the mild WML and control group. The dominant auditory centre was activated in the control or mild WML groups, but not in the moderate WML and severe WML groups.Interpretation: WML gradually affect auditory and speech development, and electrophysiological performance pCI in prelingually deaf children.What This Paper Adds: Auditory and speech performance in prelingually deaf children with white matter lesions (WML) was significantly worse than those without WML. Postoperative auditory and speech performance in children with WML was highly related to WML grading. Grand N1 amplitude in auditory event-related potentials was negatively related to the severity of WML. Non-dominant areas close to the auditory cortex were potentially activated in severe WML. [ABSTRACT FROM AUTHOR]

Currently, virtual synchronous generator (VSG) technology is proposed to be a solution to stability controlling of micro-source inverter. However, the deviation from phase locked loop (PLL) influences the reference frequency calculating which is important to the VSG control system. This paper focuses on the virtual inertia controller in the VSG control system, an enhanced controller is achieved for avoiding the effect of PLL on the VSG dynamics. For analysing dynamic characteristics of the enhanced VSG control system, the linearised small-signal model of VSG in isolated operation is well established, including electrical system, enhanced virtual inertia controller, voltage and current controller, virtual impedance, and droop controller. By small-signal stability analysis, the influence rules of the main parameters (load, line, virtual inertia and proportional-Integral gain) on VSG system impacts are provided, which helps identifying possible feedback signals for controller design to improve the system stability. Results obtained from time-domain small-signal model are compared with those from the electrical simulation to verify its accuracy. [ABSTRACT FROM AUTHOR]

This single‐center, randomized, open, two‐preparation, single‐dose, two‐period, self‐crossover trial aimed to assess the bioequivalence and safety of the test (T) preparation compared to the reference (R) preparation following intravenous injection in healthy subjects under fasting conditions. Twenty‐four healthy subjects were enrolled in the study and subjects were randomly divided into two groups at a 1:1 ratio and were administered once per period, with an 8‐day washout period. During each period, serum drug concentrations were detected for pharmacokinetic analysis and adverse events were recorded for safety analysis. The 90% confidence intervals for the geometric mean ratios (T:R) of maximum serum concentration, area under the serum concentration‐time curve from time zero to the last measurable concentration, and area under the serum concentration‐time curve from time zero to infinite time fell within the predefined bioequivalence range of 80%–125%, indicating bioequivalence between the T and R preparation under fasting conditions. Additionally, four subjects (16.7%) experienced five instances of adverse events in the T group, while five subjects (21.7%) experienced five instances of adverse events in the R group. This trial indicated the potential bioequivalence between the T and R products under fasting conditions, based on pharmacokinetic and safety profile. [ABSTRACT FROM AUTHOR]