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The optimization of planar transformers with integrated magnetic components is an important research focus when it comes to high efficiency and high power density step-down DC–DC converters. In this paper, to overcome the shortcomings of LLC topologies in variable frequency operation, a DC–DC converter of two-stage regulation with GaN (gallium nitride)–MOSFET is designed to achieve wide voltage range conversion. The planar transformer of the full-bridge LLC circuit is optimized at 12 V DC bus and high-power scenarios. An equivalent resonant inductance model based on the stray inductance and JMAG leakage inductance simulation is proposed, which results in only one magnetic component being used in the LLC. A method to control the resonant inductance and improve the efficiency by changing the PCB trace on the secondary side of the high-step-down-ratio (14:1:1) planar transformer is proposed. To verify the optimization model, two sets of converters with optimized planar transformers, using PQ-type ferrite magnetic cores, have been built. Experimental results show that the voltage conversion range is from 250–500 to 9–16 V, and the converter efficiency is increased to 94.39%@3 kW.

The prevalence of physical inactivity and increasing rates of obesity are one of the most important public health issues in the United States. While obesity in general is a contributing [...]

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Cytochrome P450 3A4 (CYP3A4) is one of the major drug metabolizing enzymes in the human body and metabolizes ∼30–50% of clinically used drugs. Inhibition of CYP3A4 must always be considered in the development of new drugs. Time-dependent inhibition (TDI) is an important P450 inhibition type that could cause undesired drug–drug interactions. Therefore, identification of CYP3A4 TDI by a rapid convenient way is of great importance to any new drug discovery effort. Here, we report the development of in silico classification models for prediction of potential CYP3A4 time-dependent inhibitors. On the basis of the CYP3A4 TDI data set that we manually collected from literature and databases, both conventional machine learning and deep learning models were constructed. The comparisons of different sampling strategies, molecular representations, and machine-learning algorithms showed the benefits of a balanced data set and the deep-learning model featured by GraphConv. The generalization ability of the best model was tested by screening an external data set, and the prediction results were validated by biological experiments. In addition, several structural alerts that are relevant to CYP3A4 time-dependent inhibitors were identified via information gain and frequency analysis. We anticipate that our effort would be useful for identification of potential CYP3A4 time-dependent inhibitors in drug discovery and design.

Aim: We aimed to identify how the COVID-19 lockdown affected changes, including the potential for longer term sustained changes, in physical activity, as compared to immediately prior to the pandemic.Background: Physical activity’s significant role in overall health is known to be influenced by the surrounding environment, such as one’s neighborhood, prompting this study of physical activity and its relationship with individual-level and neighborhood-level factors within the pandemic timeline.Methods: A statewide online survey assessed adults’ self-reported weekly minutes of moderate-to-vigorous physical activity (MVPA) comparing a typical week immediately prior to the pandemic and during the pandemic (prewidespread vaccination) using negative binomial models.Results: Overall, MVPA decreased during the pandemic, though the decrease was driven largely by the reduction in MVPA outside one’s neighborhood. In contrast, MVPA done within one’s neighborhood increased over time. This change in MVPA done within one’s neighborhood was not uniform across several characteristics including income level favoring those with the highest income (p< .05) and race/ethnicity favoring those self-reporting as non-Hispanic White (p< .05). While several factors, including higher Walk Scores, were associated with higher levels of MVPA without evidence of change over time, evidence of a differential effect over time was seen for other key indicators of social and structural determinants of health including income and race/ethnicity.Conclusions: This study can add to the existing literature surrounding not only COVID-19 but also neighborhood built environmental research seeking to identify factors associated with changes in MVPA, a known indicator of overall health and health-related outcomes.

We reported a χ-Fe5C2/MgO catalyst for olefin synthesis directly from syngas (STO), showing high selectivity to C2–C4olefins and catalytic stability. With characterization of the morphology, electronic structures, and adsorption/desorption properties using in/ex situtechniques (XPS, TEM, XRD, MES, PHTA and TPD), we revealed that MgO could act not only as a structural promoter to disperse the active iron phase and prevent particle agglomeration during the reaction, but also as an electronic modifier to transfer electrons to iron. In particular, by combination of spectroscopy and theory calculations, we have proved that the close intimacy between χ-Fe5C2and MgO (∼0.3 electrons transfer from MgO to χ-Fe5C2) enhanced CO dissociative adsorption whilst weakening the secondary hydrogenation of olefins, leading to the enhancement of selectivity. The dual roles of MgO in χ-Fe5C2/MgO may shed light upon rational design of practical STO catalysts by taking advantage of the exceptional strong metal–support interactions (SMSIs).

Anthropogenic disturbances may decrease as we take measures to control them. However, the patterns and mechanisms of post-disturbance ecosystem succession have rarely been studied. Here we reported that disturbance level determined the importance of stochastic relative to deterministic changes in ecosystem components (plant community composition, soil microbial community composition, and soil physicochemical indices), and thus predefined the pattern of post-disturbance ecosystem succession. We proposed a theoretical framework with five disturbance levels corresponding to distinct succession patterns. We conducted a nitrogen addition experiment in a temperate steppe, monitored these ecosystem components during “disturbance” treatment (2010–2014) and post-treatment “succession” (2014–2018). The disturbance level experienced by each component in each treatment was inferred by fitting the observed succession patterns into the theoretical framework. The mean disturbance level of these components was found to increase quadratically with nitrogen addition rate. This was because increasing nitrogen addition reduced the importance of stochastic relative to deterministic changes in these components, and these changes had a quadratic relationship with disturbance level. Overall, our results suggested that by monitoring the importance of stochastic relative to deterministic changes in an ecosystem, we can estimate disturbance levels and predict succession patterns, as well as propose disturbance-level-dependent strategies for post-disturbance restoration.

Increasing evidence suggested that bacterial infection diseases posed a great threat to human health and became the leading cause of mortality. However, the abuse of antibiotics and their residues in the environment result in the emergence and prevalence of drug-resistant bacteria. Photothermal therapy (PTT) has received considerable attention owing to its noninvasiveness, and proved to be promising in preventing bacterial infection diseases. In this review, we first surveyed the recent progress of PTT-based responsive targeting strategies for bacterial killing. We then highlighted the PTT-based smart designs of bio-films, hydrogels and synergistic methods for treating bacterial infections. Existing challenges and perspectives are also discussed to inspire the future development of a PTT-based platform for the efficient therapy of bacterial infections.

Background Acute ischemic stroke poses a significant health threat, and thrombectomy has become a routine treatment. Tirofiban has emerged as a promising adjunct therapy to minimize reocclusion after thrombectomy. We aimed to investigate whether renal function influences the safety and efficacy of tirofiban in patients undergoing endovascular therapy.Methods Patients' clinical data collected from the stroke unit were analyzed. The modified Rankin scale score and symptomatic intracranial hemorrhage (sICH) were used as outcome measures.Results A total of 409 patients (mean age: 66.5 years, 292 males [71.4%]) were included. Tirofiban significantly improved 3-month functional outcomes (adjusted odds ratio [aOR] = 2.408, 95% confidence interval [CI] 1.120–5.175), reduced 3-month mortality (aOR = 0.364, 95% CI 0.155–0.856), and decreased the incidence of sICH (aOR = 0.339, 95% CI 0.149–0.767) in patients with estimated glomerular filtration rate (eGFR) ≥ 90 mL/min/1.73 m². However, no significant improvement in prognosis was observed with tirofiban in patients with eGFR < 90 mL/min/1.73 m². Interaction analysis suggested a potential influence of renal function on tirofiban efficacy.Conclusion Renal function may impact the efficacy of tirofiban. Administration of tirofiban in direct thrombectomy patients with normal renal function is safe and improves prognosis. However, the prognostic benefits of tirofiban are limited in patients with impaired renal function.

Abstract Present study reports a controllable phase transformation of nickel (Ni) from amorphous to cubic crystal structures on tungsten (W) substrate by electrodeposition. X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive spectroscopy were used to characterize the microstructure, micro-constituents and surface morphology of as-prepared Ni. The microstructure of Ni was strongly affected by the applied overpotential and deposition time. It is demonstrated that by controlling these two parameters either amorphous or cubic crystal structure of Ni on the W substrate could be obtained. The crystallization mechanism is discussed based on Gibbs crystal growth theory and Ostwald's rule. It is concluded that W substrate, acting as a heat sink, can effectively promote the thermal stability of amorphous Ni, based on the data from differential scanning calorimetry and Kissinger's model. This work contributes to the elucidation of the crystallization mechanism of Ni on W powder substrates, and proves that, better than alloying with other elements, incorporating powder substrates will significantly improve the crystallization temperature, hence the thermostability of amorphous Ni. [ABSTRACT FROM AUTHOR]

GNE myopathy is a rare autosomal recessive distal myopathy caused by mutations in UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE), the bi-functional enzyme critical for sialic acid biosynthesis. In this study, we summarized the clinical features, pathological characteristics, and genetic profiles of 46 GNE patients. The clinical and mutational profile of 54 previously reported Chinese patients were also reviewed. A total of 21 novel mutations, including a gross deletion spanning exon 1–2 and a retrotransposon insertion were found in our cohort, enlarging the spectrum of GNEmutations. The most frequent mutation in Chinese population was D207V, which accounts for 25.5% of total alleles (51/200). The age of onset was much later in the patients carrying D207V compared to other patients, indicated the less deleterious effect of D207V on enzyme activity. GNE myopathy may be overlooked in China with a relatively milder phenotype due to the common mutation D207V.

Objectives: This study investigated the resilience of single-family housing values in walkable versus unwalkable neighborhoods during the economic downturn from 2008 to 2012 in Dallas, Texas.Methods: Using propensity score matching and difference in differences methods, this study established a natural experimental design to compare before-and-after value changes of single-family (SF) homes in walkable neighborhoods with unwalkable neighborhoods during the Great Recession. Two thousand seven hundred ninety-nine SF homes within 18 Tax Increment Financing (TIF) districts were categorized into walkable (Walk Score ≥50) and unwalkable (<50) groups. Six hundred twenty-four dwellings in walkable neighborhoods were matched with the most identical ones in the unwalkable neighborhoods by controlling for the selected structural and residential location variables. Relative average treatment effects were examined for SF values in walkable and unwalkable neighborhoods.Results: On average, the SF homes in walkable neighborhoods held $4566 (2.08%) more value than their how walkable counterparts.Conclusions: This study aims to help planners and decision-makers by documenting the unmet demand for walkable communities and their sustained economic benefit. Increased awareness of the sustained value of walkable communities can be used by lenders who finance and by policy makers who regulate placemaking. Results from this study can be integrated with research that demonstrates health-care cost savings of walkable environments to create an even more comprehensive set of evidence-based interventions to increase their supply.

Complete Streets are designed to allow for safe access and use for all (e.g., pedestrians, bicyclists, transit commuters, motorists) to improve mobility and accessibility. Retrofitting Complete Street designs acts as an intervention by increasing active transportation activity and providing safety benefits (e.g., reducing motor vehicle involved crashes and injuries); however there is insufficient evidence related to economic benefits of this redesign.

Despite the mounting attention being paid to vegetation growth and their driving forces for water-limited ecosystems, the relative contributions of atmospheric and soil moisture dryness stress on vegetation growth are an ongoing debate. Here we comprehensively compare the impacts of high vapor pressure deficit (VPD) and low soil water content (SWC) on vegetation growth in Eurasian drylands during 1982–2014. The analysis indicates a gradual decoupling between atmospheric dryness and soil dryness over this period, as the former has expanded faster than the latter. Moreover, the VPD–SWC relation and VPD–greenness relation are both non-linear, while the SWC–greenness relation is near-linear. The loosened coupling between VPD and SWC, the non-linear correlations among VPD–SWC-greenness and the expanded area extent in which SWC acts as the dominant stress factor all provide compelling evidence that SWC is a more influential stressor than VPD on vegetation growth in Eurasian drylands. In addition, a set of 11 Earth system models projected a continuously growing constraint of SWC stress on vegetation growth towards 2100. Our results are vital to dryland ecosystems management and drought mitigation in Eurasia.This study reveals a gradually decoupled relationship between atmospheric and soil moisture dryness in Eurasian drylands. As time goes by, the relative influential magnitude of soil moisture dryness stress on dryland ecosystems strengthens, while that of atmospheric dryness weakens and this relative dominance will persist into the future warming.

A competitive indirect enzyme-linked immunosorbent assay (ELISA) was developed and successfully applied in a dissolved mercury assay. For mercury quantification, factors including the concentration of chelator EDTA, pH, ionic strength, and blocking solution were optimized in this study. Generally the detection limit of the ELISA was standardized as 0.459 μg L−1, with an IC50value of 13.09 μg L−1and linear range of 1 to 500 μg L−1; whereas a cross-reactivity study showed that the immunoassay was quite specific for mercury, compared with nine other metal ions. The recovery of the method was evaluated by spiking ultrapure water, tap water and surface water of Taihu Lake with mercury at 1, 10, 50, 100 μg L−1. The precision of the method was evaluated by spiking ultrapure water with mercury at 1, 10, 50, and 100, 500 and 1000 μg L−1. The coefficients of variation of intra- and inter-assay were below 10% in most cases, and recoveries were 94.3–123.5%, 91.9–117.9%, and 92.3–115.6% for ultrapure water, tap water and surface water of Taihu Lake, respectively. Therefore, the developed method is able to determine mercury at levels below the maximum residue limits of water quality standards for drinking water sources of China.

This article analyzes the relationship between urban development and housing prices in China. When comparing data from three recent consecutive years, with some exceptions, the result shows that in general, housing price is determined by urban development in most urban regions. The article summarizes strategies for affordable housing development and housing policy in China, and analyzes the implications of this study for social work and education. It advocates comprehensive new thinking on a broader topic: how to maintain healthy housing prices and stable development in China.

The promotional effects of sodium on Fe5C2catalysts for CO2hydrogenation were systematically investigated by a synergistic combination of density functional theory (DFT) calculations and experimental methods. Na was found to markedly alter the electronic structure of Fe5C2surface, leading to a reduction of the CO2dissociation barrier from 0.45 to 0.08 eV and a decrease of the hydrogen binding energy. Moreover, Na lowers methane’s selectivity by hindering further hydrogenation of CH2and enhances C–C coupling probability by promoting the chain growth of CH2. Additionally, Na strengthens alkenes’ selectivity by facilitating dehydrogenation of alkyls and boosting the desorption of alkenes. The theoretical findings were confirmed by experimental results. Adding Na to Fe5C2catalyst was found to facilitate CO2conversion and alkenes’ selectivity. Especially, the O/P (olefin/paraffin) ratio of C2–C4hydrocarbons increases from 2.0 to 9.7 and the C5+hydrocarbons’ selectivity increases from 12.6% to 51.8%. This study further deepens the understanding of the promotional effect of sodium on Fe-based catalysts for CO2hydrogenation and enlightens the rational design of highly selective catalysts.

The traditional process similarity calculation method has a large amount of calculation and the calculation process is cumbersome. For the case of long process routes and long codes, the calculation difficulty and running time increase rapidly, and the operation effect is not good. In this paper, a process similarity analysis algorithm based on the longest sub-similar sequence set is proposed. Compared with the traditional calculation method, this algorithm has the advantages of high operating efficiency and strong adaptability. Further considering the influence of continuous similar process sequences, the penalty factor is introduced to improve the algorithm, so that the algorithm is more perfect and reasonable. This algorithm has significant application value in modern manufacturing systems.

Since the publication of the above article, the authors of the above paper have noticed errors in Author’s affiliation.

In this paper, a new type of grinding wheel and its manufacturing production process are introduced. The new BCB (Bamboo Charcoal Bond) grinding wheel was made of bamboo charcoal, phenolic resin and abrasive powder with higher press and temperature. To investigate its mechanical features, such as Rockwell hardness, resistance to abrasion, and resistance to pressure, some experiments on three BCB samples with different Resin weight ratios 20%, 25%, 30%, were carried out. The results showed that the BCB sample with proper moulding process and Resin weight ratio had better performance.