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Quantum dot sensitized solar cells (QDSCs) represent a promising third‐generation photovoltaic technology, boasting a high theoretical efficiency of 44% and cost efficiency. However, their practical efficiency is constrained by reduced photovoltage (Voc) and fill factor (FF). One primary reason is the inefficient charge transfer and elevated recombination rates at the counter electrode (CE). In this work, a novel CE composed of a titanium mesh loaded with Co,N─C@MoS2 is introduced for the assembly of QDSCs. The incorporation of nanosized MoS2 enhances the density of catalytic sites, while the Co,N─C component ensures high conductivity and provides a substantial active surface area. Additionally, the titanium mesh's 3D structure serves as an effective electrical conduit, facilitating rapid electron transfer from the external circuit to the composite. These improvements in catalytic activity, charge transfer rate, and stability of the CE significantly enhance the photovoltaic performance of QDSCs. The optimized cells achieve a groundbreaking power conversion efficiency (PCE) of 16.39%, accompanied by a short‐circuit current density (Jsc) of 27.26 mA cm−2, Voc of 0.818 V, and FF of 0.735. These results not only offer a new strategy for designing electrodes with high catalytic activity but also underscore the promising application of the Co,N─C@MoS2 composite in enhancing QDSC technology. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations are employed to assess the effects of diverse carbon nanomaterials on the thermo‐oxidative aging properties and tribological behavior of perfluoroelastomer (FFKM) in high‐temperature environments. In this study, carbon nanofillers such as graphene nanosheets (GNS), carbon nanotubes (CNTs), hydroxyl‐functionalized graphene (OH‐GNS), and hydroxyl‐functionalized carbon nanotubes (OH‐CNTs) are examined. The aging properties of composite systems are characterized by parameters like cohesive energy density and mean square displacement. The constant strain method is utilized to estimate the shear modulus and bulk modulus. Three‐layer friction structures are established to analyze the mechanism of fillers on the tribological behavior of composites by applying shear loads. According to the MD simulation results, the addition of carbon nanofillers enhances FFKM's thermo‐oxidative aging performance at 533 K, increases its bulk and shear moduli, and reduces the coefficient of friction and abrasion rate of each composite at high temperatures. Among the four nanofillers, OH‐CNTs is the most effective in terms of improving FFKM performance. Stronger dipoledipole interactions and hydrogen bonding are introduced into the system by OH‐CNTs, which improves the stability of the filler‐matrix interface and produces stronger interfacial interactions. This work offers theoretical predictions for the design and optimization of carbon nanomaterial and FFKM polymer composites. [ABSTRACT FROM AUTHOR]

Litter decomposition is critical for maintaining productivity and nutrient cycling in forest ecosystems. Large herbivores play an essential role in determining the processes of nutrient cycling. Asian temperate forests are becoming degraded and fragmented by the widespread intensification of anthropogenic activities, including excessive livestock grazing. However, the effects of livestock grazing and wild ungulates on forest litter decomposition remain less explored. In this study, we used a litterbag experiment to investigate the effects of the addition of cattle (Bos taurus) and sika deer (Cervus nippon) feces on litter decomposition. The study was conducted in Northeast China from July 2022 to October 2023. We found that the addition of deer feces significantly reduced litter decomposition, but the addition of cattle feces greatly increased litter decomposition. The presence of cattle and deer excrement significantly accelerated the release of C after 1 year of litter decomposition. Compared with the results of the control group (no addition of feces), the addition of cattle and sika deer feces increased C release by 37.45% and 22.69%, respectively. Fecal addition increased the release of N; however, for the three treatment groups, the maximum accumulation of N occurred in the middle of litter decomposition, which may have been due to the initial chemical quality of the leaves and snow melt as well as nutrient limitations at the sites. Compared with the results of the control group, P release in the feces of cattle increased by 4.35%, but P release in the feces of deer decreased by 27.55%. This work highlights that feces deposition by large herbivores (e.g., wild or domestic) in the forest has nonequivalent effects on litter decomposition. Such effects may further alter the nutrient cycling in temperate forest ecosystems, with far‐reaching effects on the ecosystem that deserve closer attention. We suggest that conservation managers should seek evidence‐based interventions to optimize livestock use of forest habitats shared with wildlife. [ABSTRACT FROM AUTHOR]

Gardenia jasminoides Ellis. polysaccharide (GPS) can protect against cholestatic liver injury (CLI) by regulating nuclear farnesoid X receptor (FXR).However, the mechanism via which GPS mediates the FXR pathway remains unclear. The aim of this study was to investigate the mechanism. Firstly, an alpha‐naphthylisothiocyanate‐induced cholestatic mouse model was administered with GPS to evaluate its hepatoprotective effects. The metabolic pathways influenced by GPS in cholestatic mice were detected by serum metabolomics. The effect of GPS on bile acid (BA) homeostasis, FXR expression, and liver inflammation were investigated. Second, the intestinal bacteria metabolites affected by GPS in vivo and in vitro were determined. The activation of FXR by sodium butyrate (NaB) was measured. Finally, the effects of NaB on cholestatic mice were demonstrated. The main pathways influenced by GPS involved BA biosynthesis. GPS upregulated hepatic FXR expression, improved BA homeostasis, reduced F4/80+ and Ly6G+ positive areas in the liver, and inhibited liver inflammation in cholestatic mice. Butyric acid was the most notable intestinal bacterial metabolite following GPS intervention. NaB activated the transcriptional activity of FXR in vitro, upregulated hepatic FXR and its downstream efflux transporter expression, and ameliorated disordered BA homeostasis in CLI mice. NaB inhibited the toll‐like receptor 4/nuclear factor (TLR4/NF‐κB) pathway and reduced inflammation and CLI in mice. An FXR antagonist suppressed the effects. In conclusion, GPS increased butyric acid production, which can activate hepatic FXR, reverse BA homeostasis disorder, and inhibit the TLR4/NF‐κB inflammatory pathway, exerting protective effects against CLI. [ABSTRACT FROM AUTHOR]

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore declines. Although studies exploring the dynamics and competition between tigers (Panthera tigris) and leopards (P. pardus) span decades, there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale, as well as the drivers determining their exploitative and interference competition. We gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models; we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and leopards. Elevation and ungulate density were the most important predictors in regulating the coexistence mechanisms. Tigers and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial niche. In addition, they showed a higher dietary overlap in the prey‐rich regions. We determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation structures. Meanwhile, studies with multiple metrics would promote the detection of interference competition. Our study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad scale. Policy‐makers and managers should pay more attention to the factors of elevation, prey abundance, and habitat structures for the conservation of tigers and leopards. [ABSTRACT FROM AUTHOR]

Previous studies have shown that various active components of licorice have anticancer effects. However, few studies have investigated the mechanism of action of licorice in gastric cancer. The effect of active compounds in licorice on the biological activity of gastric cancer cells was investigated in vitro (MKN-45 cells). Network pharmacology and molecular docking were used to predict the potential targets of licorice against gastric cancer and verify the binding stability of target proteins to compounds. In addition, the anticancer effect of licorice was assessed using a mouse model of gastric cancer. The licorice-active component (quercetin) effectively inhibited proliferation, caused cell cycle arrest, and promoted apoptosis in MKN-45 cells, accompanied by increased Cyt-C, decreased BCL-2, and decreased mitochondrial membrane potential and mitochondrial damage. Further research showed that quercetin targeted EGFR, blocked the ERK signaling pathway, and downregulated PTGS2. In the in vivo experiment, quercetin treatment resulted in reduced tumor volume, decreased Ki67 and BCL-2 expression in tumor tissue, increased caspase 3 and BAX levels, and induced mitochondrial damage. [ABSTRACT FROM AUTHOR]

Mineral licks are indispensable habitats to the life history of large mammal herbivores (LMH). Geophagy at licks may provide the necessary minerals for LMH, while LMH may be ecosystem engineers of licks by altering vegetation cover and soil physicochemical properties (SPCP). However, the precise relationship between the LMH and licks remains unclear. To clarify the geophagy function of licks for LMH and their influence on soil at licks, we recorded visitation patterns of sika deer around licks and compared SPCP and microbial communities with the surrounding matrix in a firebreak adjacent to the Sino‐Russian border. Our study indirectly supports the "sodium supplementation" hypothesis. Proofs included (1) a significantly higher sodium, iron, and aluminum contents than the matrix, while lower carbon, nitrogen, and moisture contents; (2) significantly higher deer visitation during sodium‐demand season (growing season), along with an avoidance of licks with high iron contents, which is toxic when overdose. The microbes at the licks differed from those at the matrix, mainly driven by low soil carbon and nitrogen and altered biogeochemical cycles. The microbial communities of licks are vulnerable because of their unstable state and susceptibility to SPCP changes. Structural equation modeling (SEM) clearly showed a much stronger indirect effect of deer on microbes at licks than at the matrix, especially for bacteria. Multiple deer behaviors at licks, such as grazing, trampling, and excretion, can indirectly shape and stabilize microbes by altering carbon and nitrogen input. Our study is the first to characterize soil microbial communities at mineral licks and demonstrate the processes by which LMH shapes those communities. More studies are required to establish a general relationship between the LMH and licks to promote the conservation of natural licks for wildlife. [ABSTRACT FROM AUTHOR]

The epitaxial growth of high‐quality and large‐area monolayer (ML) MoS2 has attracted widespread attention in recent years. Here, MoS2 on Al2O3 substrate was prepared by using atmospheric‐pressure chemical vapor deposition. The process parameters such as temperature difference and distance between MoO3 and Al2O3, nucleation temperature, and heating rate were optimized. The high MoO3 evaporation temperature facilitates Mo vapor transport to grow ML‐MoS2. The introduction of nucleation temperature facilitates the deposition of MoS2, and the morphology of the nucleation point is related to the amount of MoO3‐x deposited on Al2O3. This process optimization method is also applicable to growth MoS2 on SiO2. The ML‐MoS2 with a size greater than 1 cm2 was successfully fabricated on Al2O3 and SiO2, which laid a foundation for the practical application of ML‐MoS2. [ABSTRACT FROM AUTHOR]

The continuation of the isolated Amur tiger (Panthera tigris altaica) population living along the China–Russia border is facing serious challenges due to factors such as its small size (including 38 individuals) and canine distemper virus (CDV). We use a population viability analysis metamodel, which consists of a traditional individual‐based demographic model linked to an epidemiological model, to assess options for controlling the impact of negative factors through domestic dog management in protected areas, increasing connectivity to the neighboring large population (including more than 400 individuals), and habitat expansion. Without intervention, under inbreeding depression of 3.14, 6.29, and 12.26 lethal equivalents, our metamodel predicted the extinction within 100 years is 64.4%, 90.6%, and 99.8%, respectively. In addition, the simulation results showed that dog management or habitat expansion independently will not ensure tiger population viability for the next 100 years, and connectivity to the neighboring population would only keep the population size from rapidly declining. However, when the above three conservation scenarios are combined, even at the highest level of 12.26 lethal equivalents inbreeding depression, population size will not decline and the probability of extinction will be <5.8%. Our findings highlight that protecting the Amur tiger necessitates a multifaceted synergistic effort. Our key management recommendations for this population underline the importance of reducing CDV threats and expanding tiger occupancy to its former range in China, but re‐establishing habitat connectivity to the neighboring population is an important long‐term objective. [ABSTRACT FROM AUTHOR]

Environmental filtering is deemed to play a predominant role in regulating the abundance and distribution of animals during the urbanization process. However, the current knowledge about the effects of urbanization on the population densities of terrestrial mammals is limited. In this study, we compared two invasive mammals (dogs Canis lupus familiaris and cats Felis silvestris) and three indigenous mammals (Siberian weasels Mustela sibirica, Amur hedgehogs Erinaceus amurensis, and Tolai hares Lepus tolai) in response to urbanization using camera trap distance sampling (CTDS) in the rural–urban landscape of Tianjin, China. We used generalized additive mixed models (GAMMs) to test the specific responses of their densities to levels of urbanization. Invasive dogs (2.63 individuals/km2, 95% CI: 0.91–7.62) exhibited similar density estimations to cats (2.15 individuals/km2, 95% CI: 1.31–3.50). Amur hedgehogs were the most abundant species (6.73 individuals/km2, 95% CI: 3.15–14.38), followed by Tolai hares (2.22 individuals/km2, 95% CI: 0.87–5.68) and Siberian weasels (2.15 individuals/km2, 95% CI: 1.06–4.36). The densities of cats, Siberian weasels, and Amur hedgehogs increased with the level of urbanization. The population densities of dogs and cats were only influenced by urban‐related variables, while the densities of Siberian weasels and Amur hedgehogs were influenced by both urban‐related variables and nature‐related variables. Our findings highlight that the CTDS is a suitable and promising method for wildlife surveys in rural–urban landscapes, and urban wildlife management needs to consider the integrated repercussions of urban‐ and nature‐related factors, especially the critical impacts of green space habitats at finer scales. [ABSTRACT FROM AUTHOR]

Tough hydrogel has attracted considerable interest in various fields, however, due to poor biocompatibility, nondegradation, and pronounced compositional differences from natural tissues, it is difficult to be used for tissue regeneration. Here, a gelatin‐based tough hydrogel (GBTH) is proposed to fill this gap. Inspired by human exercise to improve muscle strength, the synergistic effect is utilized to generate highly functional crystalline domains for resisting crack propagation. The GBTH exhibits excellent tensile strength of 6.67 MPa (145‐fold that after untreated gelation). Furthermore, it is directly sutured to a ruptured tendon of adult rabbits due to its pronounced toughness and biocompatibility, self‐degradability in vivo, and similarity to natural tissue components. Ruptured tendons can compensate for mechanotransduction by GBTH and stimulate tendon differentiation to quickly return to the initial state, that is, within eight weeks. This strategy provides a new avenue for preparation of highly biocompatible tough hydrogel for tissue regeneration. [ABSTRACT FROM AUTHOR]

High‐throughput sequencing and metabarcoding techniques provide a unique opportunity to study predator–prey relationships. However, in animal dietary preference studies, how to properly correct tissue bias within the sequence read count and the role of interactions between co‐occurring species in metabarcoding mixtures remain largely unknown. In this study, we propose two categories of tissue bias correction indices: sequence read count number per unit tissue (SCN) and its ratio form (SCN ratio). By constructing plant mock communities with different numbers of co‐occurring species in metabarcoding mixtures and conducting feeding trails on captive sika deer (Cervus nippon), we demonstrate the features of the SCN and SCN ratio, evaluate their correction effects and assess the role of species interactions during tissue bias correction. Tissue differences between species are defined as the differential ability to generate sequence counts. Our study suggests that pure tissue differences among species without a species interaction is not an optimal correction index for many biomes with limited tissue differences among species. Species interactions in mixtures may amplify tissue differences, which is beneficial for tissue bias correction. However, caution must be taken because varied species interactions among communities may increase the risk of worse correction. Correction effects based on the SCN and SCN ratio are comparable, but the SCN is less influenced by control species than the SCN ratio. Based on our study, several suggestions are provided for future animal diet studies or other high‐throughput sequencing studies containing tissue bias. [ABSTRACT FROM AUTHOR]

The rain removal method based on CNN develops rapidly. However, convolution operation has the disadvantages of limited receptive field and inadaptability to the input content. Recently, another neural network structure Transformer has shown excellent performance in natural language processing and advanced visual tasks by modeling global relationships, but Transformer has limitations in capturing local dependencies. To address the above limitations, we propose the combination network of CNN and Transformer, which fully combines the advantages of CNN and Transformer structure to complete the task of image restoration. We use CNN to provide preliminary output and adopt Transformer architecture to further optimize the output of CNN. In addition, by using some key designs in module connection, our model strengthens feature propagation and encourages feature reuse, allowing better information and gradient flow. The experimental results show that compared with the existing methods, our method can remove the rain lines more comprehensively and achieve the state-of-the-art results. Besides, the experimental results also demonstrate that the CNN structure can be effectively combined with Transformer to fully utilize the superiority of different structures. [ABSTRACT FROM AUTHOR]

Da‐Huang‐Xiao‐Shi decoction (DHXSD) is a traditional Chinese medicine formula and is used to treat cholestasis. In this study, we developed a reliable and comprehensive HPLC coupled with a linear ion trap–Orbitrap mass spectrometry method for the separation and determination of 21 components including six alkaloids, five anthraquinones, three tannins, three terpenes, two iridoid glycosides, one organic acid and one flavonoid in DHXSD. A C18 column was eluted using a gradient mobile phase at a flow rate of 1 ml/min. Detection was operated with an electrospray ionization source in positive and negative ion modes using selective ion monitoring. The calibration curves for all analytes showed good linearity (r > 0.9901), and the inter‐ and intra‐day precision did not exceed 4.98%. The recovery, repeatability and stability were also within the acceptable limits. The method was successfully applied to determine multiple active constituents in DHXSD and its constituent herbs. Compared with Da Huang, the total contents of the five anthraquinones were significantly higher in DHXSD. However, the changes in the components from Zhi Zi/Huang Bo were complicated in DHXSD. The study could serve as a fundamental reference for establishing comprehensive DHXSD quality control measures and be helpful to understand some compatibility laws of DHXSD. [ABSTRACT FROM AUTHOR]

Aim: Asian forests are becoming increasingly degraded and fragmented by the extensive intensification of anthropogenic activities; these activities threaten wildlife and ecosystem sustainability. Facing a defaunation crisis, managers need more information on species assemblages to guide conservation efforts. We tested the relative influence of natural and anthropogenic factors on mammalian species richness and occupancy in temperate forests in Northeast Asia. Location: Northeast China. Methods: Camera‐trapping data and multispecies occupancy models were used to estimate the species richness of a terrestrial mammal community in a working landscape and assess community‐, group‐, and species‐specific responses to natural and anthropogenic features while accounting for imperfect detection. Species were grouped based on body size, diet and activity pattern. Results: We deployed 138 cameras and photographed 21 mammalian species over 22,976 trap days across the China–Russia border. Both natural and anthropogenic correlates varied in their importance in predicting the presence of different animals. Vegetation cover and cattle were found to have significantly positive and negative influences on community‐level mammalian occupancy, respectively. The positive relationship with vegetation cover was most evident for large or diurnal species; the negative relationship with cattle was most evident for diurnal and wild ungulate species. Large species occupancy was also negatively associated with human settlements. The predicted richness across each station varied from 5 to 14 unique species, and species had a mean occupancy probability of 0.45 (95% credible interval = 0.09–0.86). Species richness was generally the lowest in livestock grazing areas and close to human settlements. Human influence is more important than the influences of vegetation and environmental variables. Main conclusions: Our results highlight that livestock grazing was the primary human disturbance that had a negative impact on species occupancy and richness. Multispecies occupancy models helped to identify drivers of biodiversity declines and will inform conservation strategies in human‐dominated landscapes in Northeast Asian forests. We suggest that landscape conservation planning seeks to maximize forest protection and ecosystem services such as biodiversity and carbon storage. [ABSTRACT FROM AUTHOR]

Bear bile is a valuable medicinal material used in traditional Chinese medicine for over 2000 years. However, developing a substitute has become necessary because of protection measures for this endangered species. The ingredients of in vitro cultured bear bile powder (CBBP) include tauroursodeoxycholic acid (TUDCA), taurochenodeoxycholic acid (TCDCA), ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA, and it has pharmacological properties that are similar to those of natural bear bile powder (NBBP). In this study, the pharmacokinetic parameters of both CBBP and NBBP were measured in rats with a new surrogate analyte LC–MS method using stable isotopes as surrogate analytes (D4‐TUDCA, D4‐TCDCA, D4‐UDCA and D4‐CDCA) with response factors validated in authentic matrix (plasma) for simultaneously monitoring the authentic analytes (TUDCA, TCDCA, UDCA and CDCA). The method validation was satisfactory for the linear regression (r, 0.9975–0.9994), precision (RSD intra‐day, 0.72–9.35%; inter‐day, 3.82–9.02%), accuracy (RE, −12.42–5.67%) and matrix effect (95.53–99.80%), along with analyte recovery (95.90–98.82%) and stability (89.48–101.81%) of surrogate analytes, and precision (RSD intra‐day, 1.06– 11.51%; inter‐day, 2.23– 11.38%), accuracy (RE, −7.40–10.76%) and stability (87.37–111.70%) of authentic analytes. We successfully applied this method to evaluate the pharmacokinetics of CBBP and NBBP in rats, which revealed the critical in vivo properties of both bear bile preparations. [ABSTRACT FROM AUTHOR]

Large carnivore populations are globally threatened by human impacts. Better protection could benefit carnivores, co‐occurring species, and the ecosystems they inhabit. The relationship between carnivores and humans, however, is not always consistent in areas of high human activities and is often mediated through the effects of humans on their ungulate prey. To test assumptions regarding how prey abundance and humans affect carnivore occurrence, density, and daily activity patterns, we assessed tiger–prey–human spatiotemporal patterns based on camera‐trapping data in Hunchun Nature Reserve, a promising core area for tiger restoration in China. Our study area contained seasonally varying levels of human disturbance in summer and winter. We used N‐mixture models to predict the relative abundance of ungulate prey considering human and environmental covariates. We estimated tiger spatial distribution using occupancy models and models of prey relative abundance from N‐mixture models. Finally, we estimated temporal activity patterns of tigers and prey using kernel density estimates to test for temporal avoidance between tigers, prey, and humans. Our results show that human‐related activities depressed the relative abundance of prey at different scales and in different ways, but across species, the relative abundance of prey directly increased tiger occupancy. Tiger occupancy was strongly positively associated with the relative abundance of sika deer in summer and winter. The crepuscular and nocturnal tigers also apparently synchronized their activity with that of wild boar and roe deer. However, tigers temporally avoided human activity without direct spatial avoidance. Our study supports the effects of humans on tigers through human impacts on prey populations. Conservation efforts may not only target human disturbance on predators, but also on prey to alleviate human–carnivore conflict. We use data from the recovering Amur tiger population in China from an extensive remote camera‐trapping study to understand the effects of humans on tigers and their prey in both space and time. Our study showed human affected tigers both by direct temporal avoidance and indirectly via the negative influence of humans on the relative abundance of the primary wild prey of tigers. [ABSTRACT FROM AUTHOR]

Berberine, a well-known plant alkaloid derived from Rhizoma coptidis, has potential applications as a therapeutic drug for diabetic nephropathy. However, the transporter-mediated renal transport of berberine remains largely unclear. This study aimed to investigate the renal transport mechanism of berberine using transfected cells, kidney slices and animal experiments. In Madin-Darby canine kidney (MDCK) cells stably expressing rat OCT2 (MDCK-rOCT2) and kidney slices, saturable and non-saturable uptake of berberine was observed, and corticosterone could inhibit the uptake of berberine, with IC50 values of 0.1 μ m and 147.9 μ m, respectively. In double-transfected cells, the cellular accumulation of berberine into MDCK-rOCT2 and MDCK-rOCT2-rMATE1 (MDCK cells stably expressing rOCT2 and rMATE1) cells was significantly higher than the uptake into MDCK cells. Meanwhile, berberine transcellular transport was considerably higher in double-transfected MDCK-rOCT2-rMATE1 cells than in MDCK and MDCK-rOCT2 cells. Corticosterone for MDCK-rMATE1 and MDCK-MDR1 and pyrimethamine for MDCK-rMATE1 at high concentrations could inhibit the efflux of berberine. In animal experiments, compared with the berberine alone group, the cumulative urinary excretion of berberine significantly decreased in the corticosterone or pyrimethamine pretreatment groups. In the rat kidney, pyrimethamine increased, and a low dose of corticosterone (5 mg/kg) decreased, the berberine concentration. However, there was no apparent change in the renal concentration of berberine in rats pretreated with corticosterone (10 or 20 mg/kg). Thus, berberine is not only a substrate of OCT2 and P-glycoprotein, but is also a substrate of MATE1. Both OCT2 and MATE1 mediate the renal vectorial transport of berberine. [ABSTRACT FROM AUTHOR]

The db/db mouse is one of the most popular animal models for type 2 diabetes mellitus, but changes in the activities of important P450s and UGTs are still not completely clear. This study was designed to investigate the alterations of major hepatic cytochrome P450s and UDP-glucuronyltransferase enzymes in db/db mice. Mouse liver microsomes (MLMs) were obtained from male db/db mice and their wild type littermates. After incubation of the substrates separately with MLMs, the samples were pooled and analysed by high-throughput liquid chromatography-tandem mass spectrometry system for the simultaneous study of nine phase I metabolic reactions and three glucuronidation conjugation reactions to determine the activity of the metabolic enzymes. Compared with normal controls, the Clint estimate for testosterone-6β-hydroxylation was lower (46%) ( p < 0.05), while the Vmax and Clint estimates for propofol O-glucuronidation were 5-fold higher ( p < 0.01) in the liver microsomes from db/db mice. There was no significant difference in phase I metabolic reactions of phenacetin- O-deethylation, coumarin-7-hydroxylation, bupropion-hydroxylation, omeprazole-5-hydroxylation, dextromethorphan- O-demethylation, tolbutamide-4-hydroxylation, chlorzoxazone-6-hydroxylation and midazolam-1-hydroxylation and in glucuronidation reactions of estradiol 3- O-glucuronidation, and 3-azido-3-deoxythymidine glucuronidation. The data suggest that, in db/db mice, the activity of Cyp3a11, catalysing testosterone-6β-hydroxylation, decreased, while the activity of UGT1a9, catalysing propofol O-glucuronidation, increased. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A sensitive, specific, accurate HPLC-MS/MS method was developed and validated for the simultaneous quantification of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid from Longhu Rendan pills in rat plasma. Chromatographic separation was performed with a Hypersil Gold C18 column using a gradient of methanol and 0.01% acetic acid containing 0.2 m m ammonium acetate as mobile phase. The analytes were quantified on a triple quadrupole mass spectrometer, operating in selected reaction monitoring mode and switching the electrospray ion source polarity between positive and negative modes in a single run. The calibration curves of catechin, epicatechin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, piperine and glycyrrhetinic acid were linear over the concentration ranges of 5-2000, 5-2000, 0.5-200, 0.5-200, 0.25-100, 0.25-100, 0.025-10 and 0.50-200 ng mL−1, respectively. The intra- and inter-assay precisions and accuracies were <11.6 and 91.9-108.2%, respectively, for all analytes. Matrix effects for all analytes were between 88.2 and 114.2%. Stability testing showed that all analytes were stable in plasma at 24 °C for 3 h, at 4 °C for 24 h, after three freeze-thaw cycles, and at −80 °C for 15 days. The method was successfully applied to an in vivo study evaluating the pharmacokinetics of multiple nonvolatile compounds following intragastric administration of Longhu Rendan pills to rats. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

As an apex predator the Amur tiger ( Panthera tigris altaica) could play a pivotal role in maintaining the integrity of forest ecosystems in Northeast Asia. Due to habitat loss and harvest over the past century, tigers rapidly declined in China and are now restricted to the Russian Far East and bordering habitat in nearby China. To facilitate restoration of the tiger in its historical range, reliable estimates of population size are essential to assess effectiveness of conservation interventions. Here we used camera trap data collected in Hunchun National Nature Reserve from April to June 2013 and 2014 to estimate tiger density and abundance using both maximum likelihood and Bayesian spatially explicit capture-recapture (SECR) methods. A minimum of 8 individuals were detected in both sample periods and the documentation of marking behavior and reproduction suggests the presence of a resident population. Using Bayesian SECR modeling within the 11 400 km2 state space, density estimates were 0.33 and 0.40 individuals/100 km2 in 2013 and 2014, respectively, corresponding to an estimated abundance of 38 and 45 animals for this transboundary Sino-Russian population. In a maximum likelihood framework, we estimated densities of 0.30 and 0.24 individuals/100 km2 corresponding to abundances of 34 and 27, in 2013 and 2014, respectively. These density estimates are comparable to other published estimates for resident Amur tiger populations in the Russian Far East. This study reveals promising signs of tiger recovery in Northeast China, and demonstrates the importance of connectivity between the Russian and Chinese populations for recovering tigers in Northeast China. [ABSTRACT FROM AUTHOR]

The hepatic cytochrome P450 enzymes play a central role in the biotransformation of endogenous and exogenous substances. A sensitive high-throughput liquid chromatography with tandem mass spectrometry assay was developed and validated for the simultaneous quantification of the products of ten metabolic reactions catalyzed by hepatic cytochrome P450 enzymes. After the substrates were incubated separately, the samples were pooled and analyzed by liquid chromatography with tandem mass spectrometry using an electrospray ionization source in the positive and negative ion modes. The method exhibited linearity over a broad concentration range, insensitivity to matrix effects, and high accuracy, precision, and stability. The novel method was successfully applied to study the kinetics of phenacetin-O deethylation, coumarin-7 hydroxylation, bupropion hydroxylation, taxol-6 hydroxylation, omeprazole-5 hydroxylation, dextromethorphan-O demethylation, tolbutamide-4 hydroxylation, chlorzoxazone-6 hydroxylation, testosterone-6β hydroxylation, and midazolam-1 hydroxylation in rat liver microsomes. [ABSTRACT FROM AUTHOR]

Graphical representation of a DNA sequence is a powerful tool for basic biological research. Based on the ordered dinucleotides, we propose a novel three dimensional (3D) graphical representation without circuit or degeneracy. Simultaneously, we derive the projection curve of the 3D graph. These two curves have good visualization for longer DNA sequences. The utility of the proposed curves is illustrated by mutation analysis, similarity analysis, and evolutionary relationships of different species. The results indicate that our method is efficient and powerful. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 [ABSTRACT FROM AUTHOR]

We have prepared a 10 vol% zirconium oxide ( ZrO2) powder aqueous ink for ink-jet printing. This ink shows severe segregation or coffee staining during drying on solid substrates. Coffee staining is suppressed by the addition of 10 wt% poly(ethylene glycol) ( PEG) to the ink formulation. However, coffee staining occurs with the PEG solution ink when drops are printed onto a substrate made from a preprinted ZrO2 powder layer. The mechanism for this phenomenon remains unknown but may be related to the draining of solvent into the powder. The stability of printed features is controlled by the overlap of printed drops and the range of line stability is shown to be consistent with models in the literature. [ABSTRACT FROM AUTHOR]

A sensitive and specific liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS/MS) method was developed and validated to simultaneously quantify 11 active compounds (coptisine, jatrorrhizine, berberine, palmatine, baicalin, baicalein, wogonoside, wogonin, rhein, emodin and aloeemodin) from Xiexin decoction (XXD) in rat plasma. Plasma samples extracted by a single-step protein precipitation procedure were separated using the gradient mode on a Dikma ODS-C column. Selected reaction monitoring scanning was employed for quantification with switching electrospray ion source polarity between positive and negative modes in a single run. Calibration curves offered satisfactory linearity ( r > 0.995) at linear range of 0.47-60 ng/mL for coptisine, jatrorrhizine, berberine and palmatine, 15-1930 ng/mL for baicalin, 20-2560 ng/mL for baicalein, 14-1790 ng/mL for wogonoside, 0.57-72.8 ng/mL for wogonin, 10-1280 ng/mL for rhein, 0.6-76.8 ng/mL for emodin and 3.0-384 ng/mL for aloeemodin. The intra- and interday precisions were less than 10.2% in terms of relative standard deviation (RSD), and the accuracies were within ±10.84% in terms of relative error (RE). It was successfully applied to the evaluation of pharmacokinetics after single oral doses of XXD were administered to rats. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we consider a characterization of the folding of 3D model proteins. In this characterization, we describe the different kinds of 3-step path conformation, then construct an augmented Hasse matrix which reflects some properties of the protein folding. This method can characterize the folding degree of 3D model proteins and evaluate the similarity/diversity of these five model proteins. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [ABSTRACT FROM AUTHOR]

A sensitive solid-phase extraction/high-performance liquid chromatographic method with ultraviolet detection was established for the analysis of salvianolic acid B in rabbit plasma. The analyte was separated on a reversed-phase column with trifluoroacetic acid-methanol-acetonitrile (70:10:20, v/v/v) as mobile phase at a flow rate of 1 mL/min, and ultraviolet detection at 315 nm. The calibration curve for salvianolic acid B was linear over the range 35-1400 µg/L with coefficients of correlation >0.999. The inter-day and intra-day precisions of analysis were <15%, and assay accuracy ranged from 95.3 to 109.1%. This method is suitable for determining salvianolic acid B in plasma and thus investigating the pharmacokinetics of salvianolic acid B. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: So far, various approaches for phylogenetic analysis have been developed. Almost all of them put stress on analyzing nucleic acid sequences or protein primary structures. In this paper, we take the physicochemical properties of amino acids into account and introduce the hydropathy profile of amino acids into phylogenetic analysis. We find that this introduction is effectual and our method may be used to complement phylogenetic analysis. [Copyright &y& Elsevier]

A 3D graphical representation of DNA sequences, which has no circuit or degeneracy, is derived for mathematical denotation of DNA sequence. Based on this graphical representation, we propose a new sequence distance measure. We make use of the corresponding similarity matrix to construct a phylogenic tree by virtue of the fuzzy theory. The examination of phylogenic tree belong to eight species illustrates the utility of our approach. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]

Tanreqing capsule (TRQC) is a formulation frequently used in traditional Chinese medicine to treat pyrexia, cough, expectoration and pharyngalgia. Since the pharmacological action of traditional Chinese medicines is closely related to their complex and diverse constituents, understanding the exact composition of TRQC is important to elucidate its clinical effectiveness and mechanism of action as well as to establish quality control methods and resolve safety issues. Herein, we employed high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry for the simultaneous quantitation of 23 bioactive compounds in five batches of TRQC; the analytes could be categorized into five types: organic acids (seven compounds), flavonoids (10 compounds), iridoids (two compounds), phenylethanoid glycosides (two compounds) and bile acids (two compounds). The calibration curves for all analytes showed good linearity (r > 0.9953), and the inter‐ and intra‐day precisions did not exceed 4.94 and 4.97%, respectively. The recoveries varied from 90.47% to 109.80%; the corresponding relative standard deviations (RSDs) did not exceed 4.94%; and the repeatability (RSD < 4.72%) and stability (RSD < 4.88%) were also within acceptable limits. Thus, this study can be viewed as a fundamental reference for setting comprehensive TRQC quality standards. [ABSTRACT FROM AUTHOR]

Political borders and natural boundaries of wildlife populations seldom coincide, often to the detriment of conservation objectives. Transnational monitoring of endangered carnivores is rare, but is necessary for accurate population monitoring and coordinated conservation policies. We investigate the benefits of collaboratively monitoring the abundance and survival of the critically endangered Amur leopard, which occurs as a single transboundary population across China and Russia. Country‐specific results overestimated abundance and were generally less precise compared to integrated monitoring estimates; the global population was similar in both years: 84 (70–108, 95% confidence interval). Uncertainty in country‐specific annual survival estimates were approximately twice the integrated estimates of 0.82 (0.69–0.91, 95% confidence limits). This collaborative effort provided a better understanding of Amur leopard population dynamics, represented a first step in building trust, and lead to cooperative agreements to coordinate conservation policies. [ABSTRACT FROM AUTHOR]