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AbstractIn order to improve the hardness of the copper surface, reduce its friction coefficient, and adjust the overall performance of the coating, a TiB2/Cu composite coating with multilayer structure was prepared by electrodeposition. The microstructure of the composite coating was analyzed by SEM and XRD. The microhardness and friction characteristics of the coating were tested, and the differences in the microstructures and properties of different coating structures were analyzed. Microstructure coatings with two layers (Cu + TiB2/Cu) and three layers (Cu + TiB2/Cu + Cu) were prepared on the copper substrate by electrodeposition. The TiB2 particles reduced the deposition rate of the TiB2/Cu composite coating by electrodeposition, by up to 29%. The TiB2 particles in the electrolyte increased the discharge voltage of the electrodeposition process. The content of TiB2 affected the microhardness, friction, and wear properties of the TiB2/Cu composite coating. The TiB2 particles increased the microhardness of the TiB2/Cu composite coating by 61%. The multilayer-structured coating prepared by electrodeposition could control the overall properties of the coating. The microhardness and friction coefficient of the TiB2/Cu + Cu coating were between those of the Cu and TiB2/Cu composite coatings. [ABSTRACT FROM AUTHOR]

Despite remarkable advances in the diagnosis of invasive fungal infections (IFIs), rapid, specific, sensitive, and cost-effective detection methods remain elusive. Due to their stability, ease of production, and specificity to signature molecules of fungal pathogens, short single-stranded sequences of DNA, RNA, and XNA, collectively called aptamers, have emerged as promising diagnostic markers. In this perspective, we summarize recent progress in aptamer-based diagnostic tools for IFIs and discuss how these tools could potentially meet the needs and provide economical and simple solutions for point-of-care for better management of IFIs. [ABSTRACT FROM AUTHOR]

[Display omitted] In this work, we report the design and fabrication of self-powered binary response PDs based on II-type heterostructures consisting of SnS x nanoflakes (NFs) and rutile TiO 2 nanorod arrays (NRs). The TiO 2 NRs effectively block light with wavelengths below 400 nm from reaching SnS x. Under 385 nm light, the photoelectrons in TiO 2 recombine with holes in SnS x at the interface due to the energy band bending, resulting in a positive photocurrent. Under 410 nm light, the photoelectrons in SnS x and the photogenerated holes in TiO 2 accumulate at the interface, overcoming the interfacial potential barriers induced by the higher Fermi levels of SnS x and inducing a negative photocurrent. Based on the bipolar response, the dual-band imaging capability without external filters and the light-encrypted OR, AND, and NOT logic gates using a single device are demonstrated. This work provides a blueprint for the development of multifunctional self-powered PDs that can simplify system architecture, reduce the energy consumption, and improve accuracy for applications, such as visual systems, light-controlled logic circuits, and encrypted optical communications. [ABSTRACT FROM AUTHOR]

Background: As an essential part of Early Essential Newborn Care, 90 minutes of mother-infant skin-to-skin contact is significant in improving maternal and infant outcomes. However, due to human resource constraints and the consideration of maternal and infant safety, it is difficult to achieve continuous uninterrupted skin-to-skin contact for at least 90 minutes during and after cesarean delivery. The aim of this study was to investigate the efficacy and safety of the continuous uninterrupted skin-to-skin contact for at least 90 minutes during and after cesarean section for exclusive breastfeeding rate during hospitalization and maternal and infant health indicators during and after cesarean delivery. Methods: This is a single-center, prospective randomized controlled trial conducted in one tertiary care hospital in China. We selected 280 cases of elective cesarean delivery in a tertiary maternal and child specialty hospital in Zhejiang Province from September 2018 to August 2022, which were randomly divided into two groups: in the conventional group, doulas performed at least 30 minutes for early continuous SSC within 10–30 minutes during and after cesarean delivery. In the EENC group, with immediate continuous SSC within 5–10 minutes of neonatal delivery until surgery is completed and continued SSC after returning to the ward. Exclusive breastfeeding rate during hospitalization and maternal and infant health indicators were compared between the groups. Results: A total of 258 cases were analyzed. Compared with the control group, the EENC group had earlier first breastfeeding initiation (13.7 ± 3.6 vs 62.8 ± 6.5 minutes, P < 0.001), longer duration of first breastfeeding (42.6 ± 9.0 vs 17.9 ± 7.5 minutes, P < 0.001), earlier onset of lactogenesis II (73.7 ± 3.6 vs 82.5 ± 7.4 hours, P < 0.001), higher breastfeeding self-efficacy score (128.6 ± 8.9 vs 104.4 ± 8.5, P < 0.001), higher Exclusive breastfeeding rate during hospitalization (88% vs 81%, P = 0.018), higher maternal satisfaction scores (18.9 ± 1.1 vs 14.0 ± 2.7, P < 0.001). Meanwhile the EENC group showed lower incidence of neonatal hypothermia (0% vs 4.6%, P = 0.014), lower neonatal hypoglycemia (0% vs 5.4%, P = 0.007) and less cumulative blood loss within 24 hours postpartum (254.2 ± 43.6 vs 282.8 ± 63.8 ml, P < 0.001). Conclusion: The implementation of EENC up to 90 minutes by caesarean doula company nurses is feasible and beneficial to maternal and infant health. Trial Registration: ChiCTR1800018195(2018-09-04). [ABSTRACT FROM AUTHOR]

High‐performance broadband photodetectors (PDs) are essential components in spectroscopy, remote sensing, imaging, and light communication applications. In this paper, Sb2Se3 nanoparticles (NPs) are uniformly deposited on TiO2 nanorod arrays (NRs) to construct a type II heterojunction with good interfacial contact by a simple two‐step potentiostatic electrochemical deposition method combined with N2 atmosphere annealing at 280, 290 and 300 °C to control the amount of Se in Sb2Se3. A good interfacial contact between Sb2Se3 and TiO2 is conducive to the separation and transport of photogenerated carriers. Sb2Se3/TiO2 PDs exhibit excellent self‐powered photoresponse in a broad spectral range from ultraviolet‐visible‐near infrared (UV‐VIS‐NIR) due to the combined effects of high light absorption, low defect density, and more suitable band alignment. The optimal parameters with a responsivity of 13.48 A W−1, detectivity of 7.9 × 1011 Jones, and response time of 18/20 µs are demonstrated for the PDs annealed at 290 °C. The excellent performance broadband Sb2Se3/TiO2 PDs are used to construct the application models in the light communication for light encryption and flaw detection. This work opens up a new strategy for Sb2Se3/TiO2 PDs in multifunctional applications. [ABSTRACT FROM AUTHOR]

Candida auris is a recently emerged human fungal pathogen that has posed a significant threat to public health. Since its first identification in 2009, this fungus has caused nosocomial infections in over 47 countries across all inhabited continents. As of May 2023, the whole-genome sequences of over 4000 strains have been reported and a diversity of mutations, including in genes known to be associated with drug resistance in other human fungal pathogens, have been described. Among them, 387 strains contained antifungal-susceptibility information for which different methods might be used depending on the drugs and/or investigators. In most reports on C. auris so far, the number of strains analyzed was very small, from one to a few dozen, and the statistical significance of the relationships between these genetic variants and their antifungal susceptibilities could not be assessed. In this study, we conducted genome-wide association studies on individual clades based on previously published C. auris isolates to investigate the statistical association between genomic variants and susceptibility differences to nine antifungal drugs belonging to four major drug categories: 5-fluorocytosine, amphotericin B, fluconazole, voriconazole, itraconazole, posaconazole, anidulafungin, caspofungin, and micafungin. Due to the small sample sizes for Clades II, V, and VI, this study only assessed Clades I, III, and IV. Our analyses revealed 15 single nucleotide polymorphisms (SNPs) in Clade I (10 in coding and 5 in noncoding regions), 24 SNPs in Clade III (11 in coding and 13 in noncoding regions), and 13 SNPs in clade IV (10 in coding and 3 in noncoding regions) as statistically significantly associated with susceptibility differences to one or more of the nine antifungal drugs. While four SNPs in genes encoding lanosterol 14-α-demethylase (ERG11) and the catalytic subunit of 1,3-beta-D-glucan synthase (FKS1) were shared between clades, including the experimentally confirmed Ser639Phe/Pro missense substitutions in FKS1 for echinocandin resistance, most of the identified SNPs were clade specific, consistent with their recent independent origins. Interestingly, the majority of the antifungal resistance-associated SNPs were novel, and in genes and intergenic regions that have never been reported before as associated with antifungal resistance. While targeted study is needed to confirm the role of each novel SNP, the diverse mechanisms of drug resistance in C. auris revealed here indicate both challenges for infection control and opportunities for the development of novel antifungal drugs against this and other human fungal pathogens. [ABSTRACT FROM AUTHOR]

Aspergillus fumigatus is a ubiquitous, critical priority human fungal pathogen. Despite its clinical importance, there is limited knowledge regarding the variations of the genome within mitochondria, the powerhouse organelle within eukaryotic cells. In this study, we leveraged publicly available, raw, whole genome sequence data isolates from 1939 to investigate the variations in the mitochondrial genomes of A. fumigatus. These isolates were isolated from 22 countries on six continents, as well as from outer space and from within the International Space Station. In total, our analysis revealed 39 mitochondrial single nucleotide polymorphisms (mtSNPs) within this global sample, and, together, these 39 mtSNPs grouped the 1939 isolates into 79 mitochondrial multilocus genotypes (MLGs). Among the 79 MLGs, 39 were each distributed in at least two countries and 30 were each shared by at least two continents. The two most frequent MLGs were also broadly distributed: MLG11 represented 420 isolates from 11 countries and four continents and while MLG79 represented 418 isolates from 18 countries and five continents, consistent with long-distance dispersals of mitogenomes. Our population genetic analyses of the mtSNPs revealed limited differentiation among continental populations, but highly variable genetic differences among national populations, largely due to localized clonal expansions of different MLGs. Phylogenetic analysis and Discriminant Analysis of Principal Components of mtSNPs suggested the presence of at least three mitogenome clusters. Linkage disequilibrium, Index of Association, and phylogenetic incompatibility analyses collectively suggested evidence for mitogenome recombination in natural populations of A. fumigatus. In addition, sequence read depth analyses revealed an average ratio of ~20 mitogenomes per nuclear genome in this global population, but the ratios varied among strains within and between certain geographic populations. Together, our results suggest evidence for organelle dynamics, genetic differentiation, recombination, and both widespread and localized clonal expansion of the mitogenomes in the global A. fumigatus population. [ABSTRACT FROM AUTHOR]

I Lodderomyces elongisporus i , a diploid ascomycete yeast, is attracting broad attention due to its increasing infection of humans. I elongisporus i infections while receiving treatments for other comorbidities during their stay in hospitals [[6], [23]], suggesting these infections were likely hospital-acquired. I elongisporus i infections also suffered from other comorbidities, the relative contribution of invasive I L i . I elongisporus i infection to the death of individual patients is often not clear. [Extracted from the article]

In an effort to reduce macroparticle defects in arc ion plating, a hollow cathode vacuum arc was added to an arc ion plating deposition chamber, so that the discharge from the hollow cathode vacuum arc was between the target and the substrate. AlTiN coatings were deposited using this technique (hollow cathode vacuum arc enhanced arc ion plating or HCVA-AIP) on high-speed steel substrates, and analyzed using scanning electron microscopy and X-ray diffraction. The hollow cathode vacuum arc was found to reduce the number and size of macroparticles in the deposited coatings and to increase the deposition rate. The hollow cathode vacuum arc also reduces the arc ion plating target voltage, by up to 29% (to 12 V) under the conditions studied here. Using this technique, the rate of Al ionization in the target is enhanced, resulting in the formation of AlN in the coating. This effect is strengthened at a higher hollow cathode vacuum arc discharge current. [ABSTRACT FROM AUTHOR]

Cryptococcus gattii species complex (CGSC) is a basidiomycete haploid yeast and globally distributed mammalian pathogen. CGSC is comprised of six distinct lineages (VGI, VGII, VGIII, VGIV, VGV, and VGVI); however, the geographical distribution and population structure of these lineages is incompletely described. In this study, we analyze published multi-locus sequence data at seven loci for 566 previously recorded sequence types (STs) encompassing four distinct lineages (VGI, VGII, VGIII, and VGIV) within the CGSC. We investigate indicators of both clonal dispersal and recombination. Population genetic analyses of the 375 STs representing 1202 isolates with geographic information and 188 STs representing 788 isolates with ecological source data suggested historically differentiated geographic populations with infrequent long-distance gene flow. Phylogenetic analyses of sequences at the individual locus and of the concatenated sequences at all seven loci among all 566 STs revealed distinct clusters largely congruent with four major distinct lineages. However, 23 of the 566 STs (4%) each contained alleles at the seven loci belonging to two or more lineages, consistent with their hybrid origins among lineages. Within each of the four major lineages, phylogenetic incompatibility analyses revealed evidence for recombination. However, linkage disequilibrium analyses rejected the hypothesis of random recombination across all samples. Together, our results suggest evidence for historical geographical differentiation, sexual recombination, hybridization, and both long-distance and localized clonal expansion in the global CGSC population. [ABSTRACT FROM AUTHOR]

Due to the negative environmental and health effects of synthetic colorants, pigments of natural origins of plants and microbes constitute an abundant source for the food, cosmetic, textile, and pharmaceutical industries. The demands for natural alternatives, which involve natural colorants and natural biological processes for their production, have been growing rapidly in recent decades. Fungi contain some of the most prolific pigment producers, and they excel in bioavailability, yield, cost-effectiveness, and ease of large-scale cell culture as well as downstream processing. In contrast, pigments from plants are often limited by seasonal and geographic factors. Here, we delineate the taxonomy of pigmented fungi and fungal pigments, with a focus on the biosynthesis of four major categories of pigments: carotenoids, melanins, polyketides, and azaphilones. The molecular mechanisms and metabolic bases governing fungal pigment biosynthesis are discussed. Furthermore, we summarize the environmental factors that are known to impact the synthesis of different fungal pigments. Most of the environmental factors that enhance fungal pigment production are related to stresses. Finally, we highlight the challenges facing fungal pigment utilization and future trends of fungal pigment development. This integrated review will facilitate further exploitations of pigmented fungi and fungal pigments for broad applications. [ABSTRACT FROM AUTHOR]

• Concomitant oncogene mutations and V3 variant indicate shorter PFS. • Baseline brain metastasis is an independent factor for overall survival. • TP53 mutations are the most common concomitant mutations. • The presence of TP53 mutations was associated with shorter PFS among patients who received ALK-TKI. Gene complexity affects the clinical outcomes of anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). Here, we reviewed the medical records of patients with NSCLC between September 2015 and December 2020 in a single institution. We examined the clinical and genomic predictors of these outcomes using multivariate Cox proportional hazards analysis. Overall, 105 patients with ALK -rearranged NSCLC were included. Echinoderm microtubule-associated protein-like 4 (EML4) was the predominant fusion partner (96.2%). Five patients (4.8%) had non- EML4 fusion partners; three had novel partners. EML4::ALK variant 3 (36.5%) was predominant. One patient had the following three subtypes: E13::A20, E6ins33::A20, and E20::A20. Median progression-free survival (PFS), but not overall survival (OS), was significantly different between patients with variants 3 and 1. TP53 was the most common concomitant mutation (21.4%). The presence of TP53 mutations was associated with shorter PFS among patients who received ALK-TKI. Patients with concomitant oncogene mutations presented significantly shorter OS and PFS than those with only ALK rearrangement. In a multivariate Cox regression model, concomitant oncogene mutations and variant 3 carrier status were prognostic factors for PFS, whereas baseline brain metastasis was a prognostic factor for OS. [ABSTRACT FROM AUTHOR]

Space vector pulsewidth modulation (SVPWM) is usually utilized in a three-phase buck rectifier to obtain low total harmonic distortion (THD) and low switching losses. When the conventional SVPWM scheme is applied, the input currents of the three-phase buck rectifier are distorted during the transition from even sector to odd sector, which will deteriorate the harmonics of input currents. In this letter, an asymmetric modulation scheme is proposed to eliminate the distortion of input currents of the three-phase buck rectifier during the transition from even sector to odd sector. The proposed modulation scheme combines two kinds of traditional asymmetric modulations in different sectors. A 1.5 kW experimental prototype of the three-phase buck rectifier with an ac input voltage of 115 V/400 Hz is built for more electric aircraft applications. The experimental results show that the THD of 1.3% can be achieved for the three-phase buck rectifier. [ABSTRACT FROM AUTHOR]

Pulsewidth modulation (PWM) strategies, including continuous PWM (CPWM) and discontinuous PWM (DPWM), have been efficiently applied in the three-phase voltage source converters (VSCs). In the three-phase VSCs, dead-time distortion is inevitable. The characteristics of the dead-time distortion of three-phase VSCs with CPWM strategies have been studied extensively, whereas those of DPWM strategies have not been studied in detail. In this article, a comparative analysis of the dead-time distortion of CPWM strategies and DPWM strategies is conducted. Furthermore, the improvement of the PWM strategies to mitigate dead-time distortion is presented. The improved PWM strategies inject the compensation signals to the modulation signals to reconstruct the dead-time voltage error, which can significantly reduce the dead-time distortion of various PWM strategies. Experimental tests are conducted and the experimental results are provided to verify the analysis results of the dead-time distortion of DPWM strategies and the improved PWM strategies. [ABSTRACT FROM AUTHOR]

We propose a simple microfluidic approach: Dissolution-After-Precipitation (DAP), to investigate regimes of carbonate rock dissolution and multiphase reactive transport. In this method, a carbonate porous medium is created in a glass microchannel via calcium carbonate precipitation, after which an acid is injected into the channel to dissolve the precipitated porous medium. Utilizing the DAP method, for the first time we realized all five classical single-phase carbonate rock dissolution regimes (uniform, compact, conical, wormhole, ramified wormholes) in a microfluidic chip. The results are validated against the established theoretical dissolution diagram, which shows good agreement. Detailed analysis of these single-phase dissolutions suggests that the heterogeneity of the porous medium may significantly impact how the dissolution patterns evolve over time. Furthermore, DAP is utilized to investigate multiphase dissolution. As examples we tested the cases of an oleic phase (tetradecane) and a gaseous phase (CO2). Results show that the presence of a nonaqueous phase in pore spaces induces the formation of wormholes despite weak advection, and these wormholes ultimately become pathways for nonaqueous phase transport. However, the transport of tetradecane in the wormhole is very slow, causing acid breakthrough into neighboring regions. This mechanism enhances lateral connectivity between wormholes and may lead to a wormhole network. In contrast, CO2 moves rapidly and continuously seeks to enter a widening wormhole from a narrower wormhole or the porous regions, generating phenomena such as ganglia redistribution and counterflow (flow of gas opposite to acid flow). Extensive independent experiments are conducted to verify the reproducibility of the observed phenomena/mechanisms and further analyze them. Real-time monitoring of fluid pressure drop during dissolution is implemented to complement microscopy image analysis. Our method can be implemented repeatedly on the same chip, which offers a convenient and inexpensive option to study pore-scale reactive transport mechanisms. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the efficacy and safety of DBPR108 (prusogliptin), a novel dipeptidyl peptidase‐4 (DPP‐4) inhibitor, as an add‐on therapy in patients with type 2 diabetes (T2D) that is inadequately controlled with metformin. Materials and Methods: In this 24‐week, multi‐centre, randomized, double‐blind, placebo‐controlled, superiority, phase III study, adult T2D patients with HbA1c levels ranging from 7.0% to 9.5% on stable metformin were enrolled and randomized (2:1) into the DBPR108 + metformin and placebo + metformin groups. The primary endpoint was the change from baseline in HbA1c at week 24 of DBPR108 versus placebo as an add‐on therapy to metformin. Results: At week 24, the least‐square mean (standard error) change from baseline in HbA1c was significantly greater in the DBPR108 group (−0.70% [0.09%]) than in the placebo group (−0.07% [0.11%]) (P <.001), with a treatment difference of −0.63% (95% confidence interval: −0.87%, −0.39%) on the full analysis set. A higher proportion of patients achieved an HbA1c of 6.5% or less (19.7% vs. 8.5%) and an HbA1c of 7.0% or less (50.0% vs. 21.1%) at week 24 in the DBPR108 + metformin group. Furthermore, add‐on DBPR108 produced greater reductions from baseline in fasting plasma glucose and 2‐hour postprandial plasma glucose without causing weight gain. The overall frequency of adverse events was similar between the two groups. Conclusions: DBPR108 as add‐on therapy to metformin offered a significant improvement in glycaemic control, was superior to metformin monotherapy (placebo) and was safe and well‐tolerated in patients with T2D that is inadequately controlled with metformin. [ABSTRACT FROM AUTHOR]

Due to the input current dead zones, the buck power factor correction converter has to set a fixed output voltage for a tradeoff between the total harmonic distortion (THD ${_\mathit{i}}$) and efficiency. Thus, many converter-cell integrated buck-type converters have been proposed to eliminate the dead zones, which unfortunately deteriorate efficiency due to the extra components.This article proposes a group of bridgeless buck-type integrated topologies. Then, a dead-zone-free bridgeless buck-type topology with a wide output voltage range is targeted for further study. The studied converter operates in the buck+flyback mode and can automatically change to flyback mode when the dead zones occur, which only requires a simple control. Moreover, an integrated transformer based on an E-E core is investigated to reduce cost and volume. The bridgeless operation modes are introduced, followed by the PF and THD ${_\mathit{i}}$ analysis to optimize its performance. Prototypes are built and tested, which confirm the effectiveness of the converter and the integrated magnetic. [ABSTRACT FROM AUTHOR]

Background: Anti-angiogenesis drugs are applicable in treating advanced non-small cell lung cancer (NSCLC); however, the related data regarding apatinib, a Chinese domestic anti-vascular endothelial growth factor receptor-2 (VEGFR-2) production, are limited. Therefore, this study explored the efficacy and safety of apatinib plus platinum doublet chemotherapy in treating patients with advanced NSCLC.Methods: Twenty-four patients with advanced NSCLC were retrospectively enrolled. All patients received platinum doublet chemotherapy combined with apatinib 250 mg daily. The objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events were analyzed.Results: Zero (0.0%), seven (29.2%), 11 (45.8%), and six (25.0%) patients had partial response (PR), stable disease (SD), and progressed disease (PD), respectively, resulting in an ORR of 29.2% and a DCR of 75.0%. The median PFS was 12.6 months (95% CI: 3.9-21.3 months) with a 1-year PFS of 56.1%, and the median OS was 18.3 months (95% CI: 13.0-23.5 months) with a 1-year OS of 73.9%. Age ≤60 years (P = 0.034), ECOG performance score 1 (vs. 2; P = 0.005), and first-line treatment (vs. second or higher line treatment; P = 0.043) correlated with longer PFS. The most common treatment-related adverse events included fatigue (83.3%), nausea (79.2%), myelosuppression (70.8), and vomiting (66.7%), while most of them were mild and manageable. Only four (16.6%) patients witnessed grade 3-4 myelosuppression.Conclusion: Apatinib plus platinum doublet chemotherapy is effective and well-tolerated in treating patients with advanced NSCLC; moreover, reduced ECOG PS and lower lines of treatment relate to its better efficacy. [ABSTRACT FROM AUTHOR]

The dead-time between the switches in the upper and the lower bridge of voltage source PWM converters produces input current distortion, called as dead-time distortion. The dead-time distortion can be compensated by trapezoidal voltage. The conventional trapezoidal voltage compensation method (TVCM) only controls the angle of the trapezoidal voltage. By the control of the angle and amplitude of the trapezoidal voltage simultaneously, an improved TVCM is proposed to further reduce the dead-time distortion. The experimental results are provided to verify the analysis results. [ABSTRACT FROM AUTHOR]

Given the telecom base transceiver station (BTS) load mission profiles, a mixed conduction mode (MCM) control for a bridgeless boost PFC converter (IPOS boost) is proposed to mainly improve its power factor and reduce the input current total harmonic distortion (THD ${_{\mathit{i}}}$) in the light-load conditions. The principle of the MCM control and the efficiency analysis are introduced. Then, the experimental verification is performed to show the control effectiveness and performance improvements. Furthermore, a mission profile-based reliability assessment for the PFC converter is presented to analyze the IPOS boost under the classical average current (AVC) control and the proposed MCM control, along with its conventional boost counterpart under the AVC control. Considering the measured efficiency data and BTS typical mission profiles in a rural area, the analysis results indicate that given 20 years of operation, the accumulated failure of the IPOS boost under the AVC controls is 0.27%, and is further decreased to 0.24% by just the software update with the proposed MCM control. By contrast, the accumulated failure of the conventional boost counterpart under the AVC control is 2.06%, much higher than the IPOS boost. [ABSTRACT FROM AUTHOR]

This study aimed to improve the performance of the continuous flow electrocoagulation (EC)-microscreen drum filter (MDF) system in treating mariculture wastewater by investigating the passivation behavior of electrodes under different factors. Using response surface methodology, the effects of salinity (10–30‰), current density (15–75 A/m2), inlet flow (100–300 L/h), and electrode's continuous working time (without polarity change) (8–40 min) on current efficiency, total suspended solids (TSS) removal, cathode, and energy consumption of the EC-MDF system were investigated. Results showed that higher salinity improved current efficiency, alleviated anode passivation, enhanced TSS removal, reduced energy consumption, but aggravated cathode passivation. The current and TSS removal efficiencies increased with the current density, whereas the energy consumption and cathode passivation were intensified. By increasing the inlet flow, the current efficiency was improved, the anode passivation and energy consumption were alleviated, but the removal of TSS depreciated. Initially, the cathode gained significant weight before decreasing slightly as the inlet flow was upped, and the inflection point was about 250 L/h. By increasing the continuous working time of the electrode without polarity change, the passivation of the anode and cathode was aggravated, resulting in lower current and TSS removal efficiencies but higher energy consumption. [ABSTRACT FROM AUTHOR]

The mitochondrial genomes are generally considered non-recombining and homoplasmic in nature. However, our previous study provided the first evidence of extensive and stable mitochondrial heteroplasmy in natural populations of the basidiomycete fungus Thelephora ganbajun from Yunnan province, China. The heteroplasmy was characterized by the presence of two types of introns residing at adjacent but different sites in the cytochrome oxidase subunits I (cox1) gene within an individual strain. However, the frequencies of these two introns among isolates from different geographical populations and the implications for the genetic structure in natural populations have not been investigated. In this study, we analyzed DNA sequence variation at the internal transcribed spacer (ITS) regions of the nuclear ribosomal RNA gene cluster among 489 specimens from 30 geographic locations from Yunnan and compared that variation with distribution patterns of the two signature introns in the cox1 gene that are indicative of heteroplasmy in this species. In our samples, evidence for gene flow, abundant genetic diversity, and genotypic uniqueness among geographic samples in Yunnan were revealed by ITS sequence variation. While there was insignificant positive correlation between geographic distance and genetic differentiation among the geographic samples based on ITS sequences, a moderate significant correlation was found between ITS sequence variation, geographical distance of sampling sites, and distribution patterns of the two heteroplasmic introns in the cox1 gene. Interestingly, there was a significantly negative correlation between the copy numbers of the two co-existing introns. We discussed the implications of our results for a better understanding of the spread of stable mitochondrial heteroplasmy, mito-nuclear interactions, and conservation of this important gourmet mushroom. [ABSTRACT FROM AUTHOR]

• Simulation of diffusion, adsorption and aggregation of multiphase molecules. • The critical aggregation concentration of NPAM molecules with kaolinite affects their interaction energy. • NPAM molecular chains are bent into clusters, which are tiled and adsorbed on the surface of kaolinite. • In the polymer solution, the NPAM molecular chains have a phenomenon of local aggregation and agglomeration. Polymers are widely used in the tertiary oil recovery process due to their high stability, light weight and low cost. However, the macroscopic experimental research of polymers is limited by its own hypothetical conditions and cannot obtain good simulation results, which is not enough to reveal the mechanism of polymer flooding. In this paper, combing chemical, computer science and molecular dynamics methods, using non-ionic polyacrylamide, a polymer flooding model is established to simulate the movement of multiphase molecules in the process of polymer flooding from the microscopic level.Studying the diffusion, adsorption and aggregation of multiphase molecules, it was found that the diffusion rate of water molecules and NPAM molecules decreases with the growth of NPAM molecular chains. When NPAM molecules reach the critical concentration of aggregation, the interaction force between NPAM and kaolinite reaches saturation. Shearing can disrupt the length of NPAM molecular chains and accelerate the diffusion of NPAM molecules. The phenomenon of local aggregation of NPAM molecular chains in polymer solution systems occurs. revealing the interaction process of multiphase molecules in the process of polymer flooding, quantifying the diffusion laws of three molecules (polymer, oil and water), and enriching the theoretical system of polymer flooding flow. [ABSTRACT FROM AUTHOR]

It is well-known that the ripple control technique benefits from fast load transient response and small cross regulation for single-inductor dual-output (SIDO) dc–dc converter. However, existing capacitor current ripple (CCR) controlled SIDO buck converter suffers from incomplete operation state and single switching path. Thus, it has a limited stable load range. In order to extend the stable load range and suppress cross regulation of SIDO buck converter in continuous conduction mode (CCM), a novel ripple control technique, called as capacitor current and capacitor voltage ripple (CCVR) control, is proposed in this article. The operation principle of the proposed CCVR controlled SIDO CCM buck converter is presented, and its discrete iterative map model is established. Furthermore, the stability and stable load range have been discussed by using bifurcation diagrams. Based on the established small signal model, Bode plots are given to show the performance in suppressing cross regulation. Finally, simulation and experiment results are provided to verify the theoretical analysis. It shows that the proposed CCVR control technique can be applied to SIDO CCM buck converter to extend its stable load range and suppress its cross regulation. [ABSTRACT FROM AUTHOR]

Inductive power transfer (IPT) systems with multiple output voltages are potential to supply a variety of loads simultaneously. This article proposes an IPT system with multiple semiactive rectifier cells (SARCs) connected in series at the receiver (Rx) side. These SARCs are independent of each other and their output voltages can be regulated individually with single receiver coil, which reduces the cost and volume. The proposed IPT configuration has the advantages of high flexibility, simple control, and no cross regulation. Considering that the SARC may cause additional reactance and lead to detuning of the Rx side, variable inductor is introduced to ensure the full tuning condition. Thus, the proposed IPT system can maintain zero phase angle operation with unity power factor in the whole load range, minimizing the reactive power losses. In addition, both primary inverter and the SARCs can achieve zero voltage switching. To verify the feasibility and validity of the proposed IPT system, an experimental prototype with two outputs of 640 W/150 V and 400 W/120 V is built. [ABSTRACT FROM AUTHOR]

Based on the current-mode switching cell (CMSC), an inductive power transfer (IPT) system with dual-output is proposed in this letter. In the proposed IPT system, two CMSCs are inversely connected in series at the Rx side. Two CMSCs operate in the positive half-cycle and in the negative half-cycle of the Rx coil current, respectively. The dual output voltages can be regulated independently. The circuit structure of the CMSC is quite simple and helps to make the Rx side more compact. The control scheme is based on Rx-side real-time regulation and thereby wireless communication links are not required. Additionally, zero voltage switching is ensured for all switches. In order to verify the theoretical analysis, an experimental prototype with 20 V/3.3 A and 5 V/3 A outputs is fabricated, and the maximum efficiency can reach 92.8%. [ABSTRACT FROM AUTHOR]

This study presents a workflow to optimize the location of CO2 injectors in order to maximize stored volume and prevent fault reactivation due to increases of pore pressure. We combine coupled reservoir flow and geomechanics simulations with neural network surrogate models and find the best injector location based on net present environmental value (NPEV). The surrogate models can complement the numerical reservoir simulations and efficiently optimize the well location and injection rate via the steepest ascent algorithm. We apply the workflow to the Brugge field, a closed synthetic reservoir that incorporates multiple faults, as an example. The surrogate model predicts a NPEV of approximately 0.19 billion carbon credits for the Brugge field, which is consistent with the corresponding reservoir simulation. NPEV will change under different safety factors that serve as an additional injection control to enhance the safety of injection. This proposed workflow could be readily applied to other similar reservoir models. [ABSTRACT FROM AUTHOR]

Inductor–capacitor–capacitor-series (LCC-S) compensation topology has been widely used in inductive power transfer (IPT) systems due to its constant coil current regardless of the load and the coupling coefficient. Usually, the inductance of transmitter coil is sensitive to misalignments of the magnetic coupler when the asymmetrical coil structure with a smaller size receiver coil is adopted. The fluctuation of the inductance of transmitter coil will increase the power losses in the primary inverter. To compensate the fluctuation of the transmitter coil inductance, a digital switch-controlled capacitor (D-SCC) for maximum efficiency point tracking (MEPT) of LCC-S compensated IPT system is proposed. Consequently, the proposed LCC-S compensated IPT system can achieve high efficiency against the fluctuation of transmitter coil inductance. In traditional switch-controlled capacitor, high- frequency current sensor is required for the synchronization between the transmitter coil current and the driver signals of the switch-controlled capacitor. Nevertheless, the drive signals of D-SCC can be generated directly by the DSP controller in the primary side without detecting zero-cross points of the transmitter coil current, which can improve the system reliability and reduce the cost. Furthermore, the MEPT based on D-SCC is easy to be implemented because only the input dc current measurement is required. A 3.3-kW prototype is presented to verify the validity of the proposed D-SCC-based MEPT. [ABSTRACT FROM AUTHOR]

To regulate the output voltage of inductor–capacitor–capacitor-series (LCC-S) compensated wireless power transfer (WPT) system, a hybrid control strategy of phase shift modulation (PSM) and a switch-controlled capacitor is presented in this article. In the proposed hybrid control strategy, LCC-S compensated WPT system can realize wide output voltage regulation with zero voltage switching (ZVS), and the reactive current in a resonant tank can be minimized in the whole voltage range. Besides, the current in the primary coil of LCC-S compensated WPT system can be regulated with PSM, which helps to reduce the power loss of the primary coil at light load. Compared with conventional dual-loop hybrid control, the proposed hybrid control can regulate two control variables with one feedback loop simultaneously. To verify the theoretical analysis, a 500-W prototype with 400-V input voltage, 100−250-V output voltage is built. The experimental results show that the inverter can realize ZVS within the whole voltage range and a peak efficiency of 94.7% can be obtained. [ABSTRACT FROM AUTHOR]

In this article, a zero-voltage switching (ZVS) series–series compensated wireless power transfer (WPT) converter with phase shift modulation is proposed, which can realize output current regulation over wide range. In the proposed WPT converter, an auxiliary LCL resonant network is connected between two midpoints of the H-bridge legs of inverter to provide the peak current for ZVS operation during the dead time, with low rms current to decrease the conduction losses. To reduce the volume of the auxiliary network, an integrated coil structure is applied and the magnetic saturation is avoided due to the orthogonal coil currents. Time-domain analysis and ZVS operation of the proposed WPT converter are performed. Design and optimization of the LCL network are performed. Experimental results of a prototype with 8−20 A adjustable output current confirm the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Campylobacter infections are a leading cause of bacterial diarrheal illness worldwide, with increasing reports of outbreaks in both developing and developed countries. Most studies investigating strain genotypes and epidemiology of Campylobacter jejuni examined on a local scale. Using the archived multilocus sequence typing data at seven loci, and associated strain metadata from the PubMLST database, here we investigated the spatial and temporal genetic structure of the global population of C. jejuni. Our analyses revealed evidence for clonal dispersals of multiple sequence types (STs) among countries and continents. However, despite the observed clonal dispersal and that most genetic variations were found within individual geographic subpopulations, both the non-clone-corrected and clone-corrected samples showed evidence of significant genetic differentiation among national and continental subpopulations, with non-clone-corrected samples showing greater differentiation than clone-corrected samples. Phylogenetic incompatibility analyses provided evidence for recombination within each continental subpopulation. However, linkage disequilibrium analyses rejected the hypothesis of random recombination across the samples. Temporally, multiple STs were found to persist across four decades and the five globally most common STs showed relatively stable frequencies over the last two decades. We discussed the implications of our results to food security, disease transmission, and public health management. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae is the major cause of invasive pneumococcal disease. However, the global population structure remains largely unexplored. In this study, we investigated the spatial and temporal patterns of genetic variation of S. pneumoniae based on archived multilocus sequence typing data from PubMLST.org. Our analyses demonstrated both shared and unique distributions of sequence types (STs) and allele types among regional populations. Among the 17 915 global STs, 36 representing 15 263 isolates were broadly shared among all six continents, consistent with recent clonal dispersal and expansion of this pathogen. The analysis of molecular variance revealed that >96% genetic variations were found within individual regional populations. However, though low (<4%), statistically significant genetic differentiation among regional populations was observed. Comparisons between non-clone-corrected and clone-corrected datasets showed that localized clonal expansion contributed significantly to the observed genetic differentiations among regions. Temporal analyses of the isolates showed that implementation of pneumococcal conjugate vaccine impacted the distributions of STs, but the effect on population structure was relatively limited. Linkage disequilibrium analyses identified evidence for recombination in all continental populations; however, the inferred recombination was not random. We discussed the limitations and implications of our analyses to the global epidemiology and future vaccine developments for S. pneumoniae. [ABSTRACT FROM AUTHOR]

A C–H arylation of thiopyran derivatives with aryl halides has been developed. Under the catalysis of Pd(OAc)2/Ag2CO3, the C–H arylation takes place at the α-position of the thiopyran ring. When dibromo-substituted compounds are used as reactants, double C–H arylations may occur on the same thiopyran ring at its α- and β-positions. [ABSTRACT FROM AUTHOR]

In this letter, a digital control strategy with a simple transfer matrix between three-phase ac input voltages and dc-link voltage is proposed for a three-phase buck rectifier (3ph-BR) under unbalanced ac input conditions. The proposed digital control strategy can eliminate both the odd harmonics of the ac input currents and the even harmonics of the output voltage ripple under unbalanced ac input conditions. Compared with the state-of-the-art control strategies, the proposed control strategy does not require the extraction of the positive sequence voltage and the negative sequence voltage, thus a three-phase lock loop and complex calculation are not required. The proposed control strategy is essentially an input voltage feedforward control, which is independent of the loop bandwidth of the feedback system. Therefore, the processing speed of the digital processor is no longer the critical factor for the 3ph-BR under the unbalanced ac input conditions. The proposed control strategy makes it possible to utilize low-cost and small-sized digital processors. An experimental prototype of a 1.5-kW 3ph-BR with the proposed control strategy is built to verify the analysis results. [ABSTRACT FROM AUTHOR]

Non-toxic, stable Cs 3 Bi 2 Br 9 halide perovskite films prepared using a one-step solution method have become the active layer of resistive switching memory. Here, we control the nucleation and growth of Cs 3 Bi 2 Br 9 perovskite by introducing an appropriate amount of HBr to adjust the supersaturation of the perovskite precursor solution, thus improving the film formation quality and optimizing the device performance. The memory prepared for this film has a significant bipolar resistive behavior with a high switching ratio of 105, a cycle time of 300 and a retention time of 104 s. In addition, the current transient response of the device under pulsed voltage is investigated. By different the pulse voltage parameters (pulse amplitude, duration and time interval) to study the variation of the device current value, the term "TJUT" is finally encoded and decoded using different the number of pulses and repetitions. [Display omitted] • Stable and non-toxic Cs 3 Bi 2 Br 9 perovskite thin films are prepared using a low-temperature solution method. • HBr is used as an additive to improve the perovskite film quality by increasing the supersaturation of the precursor. • The prepared memristor has higher switching ratio, better cycle stability and retention characteristics. • The encoding and decoding process is achieved by changing the number of electrical pulses and the number of repetitions. [ABSTRACT FROM AUTHOR]

In this article, the sector update delay (SUD) of the digital control three-phase six-switch (3 ph–6 s) buck power factor correction (PFC) converter is analyzed. SUD of 3 ph–6 s buck PFC converter results in the increase of switching loss and input current distortion at the transition from even sector to odd sector. For applications when ac input frequency is 47–63 Hz, the effect of SUD is relatively small, and SUD is usually ignored. However, for applications of high ac input frequency, e.g., 360–800 Hz, the SUD of 3 ph–6 s buck PFC converter seriously affects its efficiency and input current total harmonics distortion (THD). In order to suppress the effect of SUD and to improve the input current THD and efficiency of 3 ph–6 s buck PFC converter over a wide ac input frequency, a time delay compensation method has been proposed in this article. The effect of SUD is verified by a 1.5-kW prototype with a low-cost microcontroller. Experimental results show that lower input current THD and higher efficiency over a wide ac input frequency have been achieved by the proposed compensation method. [ABSTRACT FROM AUTHOR]

Pulse train (PT) control strategy for the boost power factor correction (PFC) converter operating in the continuous conduction mode (CCM) is proposed and studied in this article. Average current mode (ACM) control is usually utilized for the CCM boost PFC converter. The ACM-controlled PFC converter suffers from poor dynamic response, because its voltage control loop has to be designed with low bandwidth to minimize the effect of low-frequency output voltage ripple on the current control loop. Different from ACM control, the voltage control loop and current control loop of the PT-controlled PFC converter are decoupled, and thus the effect of low-frequency output voltage ripple on the current control loop is eliminated. Besides, PT modulation is utilized in the proposed controller to regulate the inductor current to follow the current reference. Thus, both high power factor and fast dynamic response can be achieved. The operation principle of the PT-controlled CCM boost PFC converter is analyzed, and a 300-W prototype is built to verify the analysis results. The experimental results show that power factor of the PT-controlled PFC converter is higher than 0.998 and the dynamic response is significantly improved. [ABSTRACT FROM AUTHOR]

In inductive power transfer (IPT) applications, load-independent output has become more popular. This letter proposes a reconstructed S-LCC topology with dual-type outputs, which can realize constant current (CC) output and constant voltage (CV) output simultaneously. The proposed reconstructed S-LCC topology uses the same number of passive components, inductor or capacitor, as conventional S-LCC topology while provides dual-type outputs, which results in reduced cost and size. Such dual-type outputs could be treated as two independent output ports without using any decoupling methods, which can simplify the parameter design significantly. The circuit model of the proposed reconstructed S-LCC topology is analyzed in detail. Comparison between the proposed reconstructed S-LCC topology and multicoil structure is performed. Experimental prototypes with 300V/1.5 kW CV output and 10A/1 kW CC output are fabricated to verify the feasibility of the proposed topology. [ABSTRACT FROM AUTHOR]

The pore structure reconstruction of the porous media is of great importance to the research of mechanisms of fluid flow in porous media. To capture the large-scale patterns in the pore space, the multiple-point statistical technique is generally adopted for porous media reconstruction. Commonly, two different schemes, i.e., the single-grid scheme and the multiple-grid scheme, can be applied for simulation realization. The selection between this two schemes and a proper data template size have thus become a new research issue, and the performance of the characteristic reproduction of the training image using this two schemes must be quantified. In this paper, a series of multiple-point statistics simulation basing on a 2D micro-CT sandstone image are proceeded using both single- and multiple-grid schemes, and different data templates are adapted for porous media reconstruction. Further, to quantify the impact of the computational schemes and setting of the data template to the simulation realizations, a number of measurements considering the pore diameter, porosity, connectivity, and permeability are implemented to fully analyze the results obtained. Results show that by using the single-point statistical method, a large template is necessary to reproduce large-scale structures. The multiple-grid template method may bring great benefits to simulation efficiency over the simple data template method, as well as the recovery of the pore long-range geometric features and seepage characteristics. With the extension of the template for the multiple-grid scheme, the simulation results show lack of variations to some extent. [ABSTRACT FROM AUTHOR]

Self-powered ultraviolet (UV) photodetectors (PDs) based on ZnO heterojunctions have attracted more attention due to the simple preparation and excellent photoresponse performance without any power supply. The self-powered UV PDs based on NiO nanoflakes/ZnO nanorod arrays (NRs) heterojunctions were fabricated by a low-cost, simple chemical bath deposition (CBD) method. The crystal quality, optical and electronic properties of ZnO NRs is modified by Al3+ ions additions in the precursor solution. The heterojunction devices with ZnO NRs grown in 0.5% Al3+ ions additions precursor solution exhibit a narrow UV spectral selectivity, high photoresponsivity R (85.12 mA/W) and detectivity D* (1.74 × 1012 cm·Hz1/2/W) and a fast response speed (~2 ms) under 378 nm UV light for low intensity irradiance (0.2 mW/cm2) at zero bias. The large built-in electric field of the NiO/ZnO heterojunction with the increased Fermi level of ZnO NRs provide a strong driving force to separate and transfer the photo-generated carriers, decrease the recombination of the carriers and then improve the photoresponse performance of heterojunction devices without external bias. [ABSTRACT FROM AUTHOR]

The 140 000 or so fungal species reported so far are heterogeneously defined based on varying criteria such as morphological, physiological, mating, and (or) molecular features. Incongruences are common among traits used to separating closely related species and it is often difficult to compare fungal taxonomic groups defined based on different species recognition criteria. Though DNA sequence-based classification and identification have been made, a consensus has not been reached, primarily due to intrinsic limitations in the proposed one or a few genes. Here, I argue that the fundamental reason for the observed inconsistencies is that speciation is a stochastic process with the emergence and fixation of different traits influenced differently by many non-deterministic factors such as population size, random mutation, mode(s) of reproduction, selection imposed by interacting biotic and abiotic factors, and chance events. Each species concept attempts to capture one or a few traits emerged in the continuous process of speciation. I propose that a genome sequence-based classification and identification system could unify and stabilize fungal taxonomy and help integrate taxonomy with other fields of fungal biology. The genomic species concept could be similarly argued for other groups of eukaryotic microbes as well as for plants and animals. [ABSTRACT FROM AUTHOR]

In this paper a model is established for unstable seepage flow with polymer concentration and pressure diffusion coupling, considering the effects of polymer molecular diffusion, adsorption, and viscoelasticity of polymer solution in the formation. The factors are close to the actual seepage parameters of the injected reservoir. For the nonlinear adsorption, the combined variable and the analytical iterative method are used to obtain the approximate analytical solution of the model. According to the concentration model, the relationship between concentration and pressure distribution is obtained. Using the model theory curve to fit the well test data, the seepage parameters of the formation are obtained, and the reflection characteristics of the unstable wellbore pressure derivative curve are analyzed. [ABSTRACT FROM AUTHOR]

Epigallocatechin-3-gallate (EGCG), a main active catechin in green tea, was reported to attenuate renal injury and hypertension. However, its effects on salt-induced hypertension and renal injury remain unclear. In the present study, we explored its effects on hypertension and renal damage in Dahl rats with salt-sensitive hypertension. We found that EGCG could lower blood pressure after 6 weeks of oral administration, reduce 24 h urine protein levels and decrease creatinine clearance, and attenuate renal fibrosis, indicating that it could attenuate hypertension by protecting against renal damage. Furthermore, we studied the renal protective mechanisms of EGCG, revealing that it could lower malondialdehyde levels, reduce the numbers of infiltrated macrophages and T cells, and induce the apoptosis of NRK-49F cells. Considering that the 67 kD laminin receptor (67LR) binds to EGCG, its role in EGCG-induced fibroblast apoptosis was also investigated. The results showed that an anti-67LR antibody partially abrogated the apoptosis-inducing effects of EGCG on NRK-49F cells. In summary, EGCG may attenuate renal damage and salt-sensitive hypertension via exerting anti-oxidant, anti-inflammatory, and apoptosis-inducing effects on fibroblasts; the last effect is partially mediated by 67LR, suggesting that EGCG represents a potential strategy for treating salt-sensitive hypertension. [ABSTRACT FROM AUTHOR]

A phase-shift pulse-frequency modulation (PS-PFM) for a full-bridge LCC resonant converter is proposed in this paper to reduce both switching frequency variation range and reactive power of a traditional PFM LCC resonant converter. Like the PFM LCC resonant converter, a PS-PFM LCC resonant converter has a wider zero voltage switching operation range than a phase-shift modulated LCC resonant converter. By integrating a voltage-controlled carrier generator, the proposed PS-PFM modulator can adjust phase-shift angle and switching frequency simultaneously, resulting in one more degree of control freedom to optimize the steady-state performance of an LCC resonant converter. A detailed analysis of the proposed PS-PFM LCC resonant converter is performed and a step-by-step parameter design procedure is given. A 500-W/48-V prototype with 100–200 V input voltage is built to verify the theoretical analysis. The maximum efficiency of the prototype reaches 95.3%. [ABSTRACT FROM AUTHOR]

In this paper the fractal theory is used to derive formulas for calculating seepage velocity, permeability, and porosity for the flow of/kids in porous media with dual fractal dimensions (capillary diameter and capillary distortion fractal dimension). The dual fractal model is applicable for most limestone reservoirs. It is shown that the percolation equation of micro-compressible fluids, or the double fractal pressure diffusion equation, is a partial differential equation. The equation is solved for the pressure drop and pressure recovery conditions. The solutions for the actual wellbore consider wellbore storage and skin Wen parameters, and a model curve of an infinite reservior is drawn. Analysis of the double fractal media shows that the traditional well test analysis methods, like the pressure drop semi-log linear curve method, pressure recovery Horner method, and Gringarten-Bourdet diagram method will bring great errors, especially when the distortion fractal dimension is large. Using the established well test model, the parameters of the limestone oil reservoir and the unstable pressure data are measured, and the accurate oil reservoir effective permeability, fractal length, and fractal dimensions are calculated. [ABSTRACT FROM AUTHOR]

Power factor correction (PFC) converter suffers from serious double-line-frequency output voltage ripple due to the difference between instantaneous ac input power and dc output power. To suppress such double-line-frequency output voltage ripple, a ripple cancellation circuit (RCC) is utilized to generate the same magnitude but 180° phase shifted double-line- frequency voltage ripple. This paper provides an insight into the relationship between control scheme and double-line-frequency ripple suppression from the perspective of audio susceptibility model. For the purpose of reducing the double line frequency ripple, the closed-loop audio susceptibility of series RCC should be designed relatively low at double line frequency. According to such requirement, a ripple controller with improved voltage feed-forward (FF) scheme and quasi-proportional-resonant (QPR) compensator is designed. As QPR compensator can increase the denominator of the closed-loop audio susceptibility, while voltage FF scheme can reduce its numerator, its magnitude at double line frequency is thus greatly reduced and double-line-frequency ripple is also significantly suppressed. Moreover, due to the flexibility of QPR compensator, the proposed ripple controller presents good ripple suppression in a different line frequency application. Finally, experimental results of a flyback PFC with buck-type RCC quasi-single-stage ac–dc converter are provided to verify the validity of the proposed ripple controller. [ABSTRACT FROM AUTHOR]

口腔种植技术和骨科植体的手术替代治疗应用已较为广泛,对于全身情况良好的患者往往可获得长期稳定的治疗效果.然而,对于骨质疏松症患者,全身进行性骨量减少及骨质结构改变,对骨内种植体的长期稳定具有一定影响.近年来,接受口腔种植及骨科手术的骨质疏松患者逐年增多,而诸多患者面临长期应用抗骨质疏松药物的问题,因此抗骨质疏松药物对种植体骨结合的影响成为医师临床综合考量的重要因素之一. [ABSTRACT FROM AUTHOR]

Vertically well-aligned ZnO nanorod arrays were synthesized on glass substrates by a two-step chemical bath deposition method. The structural and luminescent properties of as-grown and air annealed samples were investigated. Scanning electron microscopy, x-ray diffraction and Raman spectra demonstrate that ZnO nanorods are well oriented with c-axis perpendicular to the substrates. Photoluminescence spectra show a weak ultraviolet emission and an intense broad visible emission band for as-grown and air annealed samples. These visible emission bands exhibit dependences of post annealing temperatures and excitation energies: (1) as the annealing temperature increases, the visible emission band gradually red-shifts from yellow to orange-red; (2) the optimal excitation energy for yellow and orange-red emission band is near the band-gap energy; (3) green emission band can be excited only by the energies lower than the band-gap energy and this emission becomes weak after high temperature annealing. A depletion region model is presented to explain the origins and red-shift of the visible emission bands. The recombination of a delocalized electron in the interstitial zinc close to the conduction band with a deeply trapped hole in the single negatively charged interstitial oxygen center in the deletion region (in the bulk) is responsible for the yellow (orange-red) emission. [ABSTRACT FROM AUTHOR]

Polycrystalline anatase Ti1-xCoxO2 (x=0–0.06) films have been fabricated by sol-gel spin coating. The effects of Co doping on the structural, optical, and magnetic properties are investigated. It is shown that oxygen vacancies and/or defects in the films are generated during thermal treatment in vacuum. Co doping reduces crystal quality and inhibits crystalline grain growth. Due to the introduction of Co, photoluminescence (PL) spectra become weak and the band gap emission has a blueshift. PL spectra reveal that the solubility of Co is lower than 0.02. At 300 K, the saturated magnetization is around 1.8 μB/Co, which is independent of the concentration of Co. This value is approximately equivalent to the average magnetic moment of bulk metallic cobalt (1.75 μB/Co). Zero-field-cooling/field-cooling measurements indicate that room temperature ferromagnetism in Co-doped TiO2 films is not an intrinsic property of the material. The presence of Co metal is identified by x-ray photoelectron spectroscopy and scanning electron microscopy. [ABSTRACT FROM AUTHOR]