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This research paper introduces an innovative technique for measuring displacement using auxetic tubular structure (ATS). The proposed displacement measurement method is based on tubular structures with a negative Poisson's ratio. It capitalizes on the underlying principle that the elastic deformation-induced change in transmittance of the ATS can be translated into a corresponding modification in the output current of the solar cell. This method allows for the conversion of the variation in light transmission into a corresponding variation in output voltage. The construction of the ATS can be achieved through 3D-printing technology, enhancing the accessibility of displacement measurement and design flexibility. The experimental results demonstrate that the proposed measurement method exhibits a linear error of less than 8% without any subsequent signal processing and achieves a sensitivity of 0.011 V/mm without signal amplification. Furthermore, experimental results also show that the proposed method has good repeatability and can maintain a high level of reliability and sensitivity when using different measurement devices. This confirms the effectiveness and feasibility of the proposed method, showing a favorable linear relationship between the input and output of the measurement system with an acceptable sensitivity, repeatability, and reliability.
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The FGF5 gene has been associated with the regulation of fibre length in mammals, including cashmere goats. A deletion variant at ~14 kb downstream of the FGF5 gene showed significant divergence between cashmere and non-cashmere goats in previous studies. In this study, we designed specific primers to genotype the deletion variant. The results of gel electrophoresis and Sanger sequencing revealed that a 507-bp deletion mutation is located at 95 454 685-95 455 191 of chromosome 6 in goats. Genotyping data from a large panel of 288 goats showed that the deletion at the FGF5 gene locus appeared to be associated with cashmere length. The deletion variant was close to fixation (frequency 0.97) in cashmere goats. Furthermore, electrophoretic mobility shift assays for evaluating DNA-protein interaction and mRNA expression levels of FGF5 suggested that the deletion variant may serve as a cis-acting element by specifically binding transcription factors to mediate quantitative changes in FGF5 mRNA expression. Our study illustrates how a structural mutation of the FGF5 gene has contributed to the cashmere growth phenotype in domestic goats. The deletion mutation within the FGF5 gene could potentially serve as a molecular marker of cashmere growth in cashmere goat breeding.
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Cabras , Animais , Expressão Gênica , Genótipo , Cabras/genética , Cabras/metabolismo , Fenótipo , RNA Mensageiro/metabolismoRESUMO
Doping in a lattice refers to the introduction of very small quantities of foreign atoms and has a generally small effect on decreasing the lattice thermal conductivity, unlike alloying which involves large fractions of other elements and strongly enhances point defect phonon scattering. Here, we report that, by alloying only 3% of In on the Cu sites of the diamond-like lattice of CuFeS2 chalcopyrite compound (Cu1-xInxFeS2, x = 0.03) has a disproportionally large effect in reducing the lattice thermal conductivity of the compound from 2.32 to 1.36 Wm-1K-1 at 630 K. We find that In is not fully ionized to +3 when on the Cu sublattice and exists mainly in the +1 oxidation state. The 5s2 lone pair of electrons of In+ makes this atom incompatible (referred to as discordant) with the tetrahedral geometry of the crystallographic site. This causes strong local bond distortions thereby softening the In-S and Cu-S chemical bonds and introducing localized low frequency vibrations. The latter couple with the base phonon frequencies of the CuFeS2 matrix enhancing the anharmonicity and decreasing the phonon velocity, and consequently the lattice thermal conductivity. The control material in which the In doping is on the Fe3+ site of the structure at the same doping level (and found in the site-compatible In3+ state), has a far smaller effect on the phonon scattering.
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With their enormous muscle mass and athletic ability, horses are well-positioned as model organisms for understanding muscle metabolism. There are two different types of horse breeds-Guanzhong (GZ) horses, an athletic breed with a larger body height (~148.7 cm), and the Ningqiang pony (NQ) horses, a lower height breed generally used for ornamental purposes-both inhabited in the same region of China with obvious differences in muscle content. The main objective of this study was to evaluate the breed-specific mechanisms controlling muscle metabolism. In this study, we observed muscle glycogen, enzyme activities, and LC-MS/MS untargeted metabolomics in the gluteus medius muscle of six, each of GZ and NQ horses, to explore differentiated metabolites that are related to the development of two muscles. As expected, the glycogen content, citrate synthase, and hexokinase activity of muscle were significantly higher in GZ horses. To alleviate the false positive rate, we used both MS1 and MS2 ions for metabolite classification and differential analysis. As a result, a total of 51,535 MS1 and 541 MS2 metabolites were identified, and these metabolites can separate these two groups from each other. Notably, 40% of these metabolites were clustered into lipids and lipid-like molecules. Furthermore, 13 significant metabolites were differentially detected between GZ and NQ horses (fold change [FC] value ≥ 2, variable important in projection value ≥1, and Q value ≤ 0.05). They are primarily clustered into glutathione metabolism (GSH, p = 0.01), taurine, and hypotaurine metabolism (p < 0.05) pathways. Seven of the 13 metabolites were also found in thoroughbred racing horses, suggesting that metabolites related to antioxidants, amino acids, and lipids played a key role in the development of skeleton muscle in horses. Those metabolites related to muscle development shed a light on racing horses' routine maintenance and improvement of athletic performance.
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Introduction: The gut microbiomes of equine are plentiful and intricate, which plays an important part in the growth. However, there is a relative lack of information on the microbial diversity in the pony's gut. Methods: In this article, 118 fecal samples from DeBa pony, NiQi pony and GuZh horse were studied by 16S rRNA amplicon sequencing. Results: Diversity analysis was used to determine the difference of gut microbiota composition among different breeds. Alpha diversity analysis showed that the gut microbiota of NiQi ponies were abundant and various. Beta diversity analysis showed that the microorganisms constitution of DeBa ponies was more similar to that of NiQi ponies. LDA Effect Size (LEfSe) analysis result that the microorganism biomarkers for NiQi pony at the genus level were Phascolarctobacterium, Paludibacter, and Fibrobacter; the bacterial biomarker for DeBa pony was Streptococcus and Prevotella; and the bacterial biomarkers for GuZh horses was Treponema, Treponema Mogibacterium, Adlercreutzia, and Blautia. The correlation analysis between genera with >1% abundance and horse height found that Streptococcus (P < 0.01), Treponema (P < 0.01), Coprococcus (P < 0.01), Prevotella (P < 0.01), Phascolarctobacterium (P < 0.01), and Mogibacterium (P < 0.01) were significantly associated with horses' height. The functional prediction results indicated that DeBa pony have a microbiota functional more similar to NiQi pony. Discussion: For the first time, our results announce the species composition and structure of the gut microbiota in Chinese ponies. At the same time, our results can provide theoretical reference for further understanding the healthy breeding, feeding management and disease prevention of horses.
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The outbreak of COVID-19 dramatically changed individuals' lifestyles, which in turn triggered psychological stress and anxiety. Many previous studies have discussed the relationships between lifestyle changes and anxiety and risk perception and anxiety independently. However, few papers have discussed these factors in a comprehensive and systematic manner. We established a six-dimensional system to assess changes in individuals' lifestyles, which include dietary habits, physical activity (PA), sleep, screen time, smoking and alcohol consumption, and interaction with neighbors. Then, we collected information relating to socio-demographics, lifestyle changes, risk perception, and anxiety, and discussed their associations using multilinear and stepwise logistic regressions. The results show that not all lifestyle changes had an influence on anxiety. Changes in PA and interaction with neighbors were not significantly associated with anxiety. Risk perception was found to be inversely related to anxiety. Changes in dietary habits, family harmony, and net income were negatively related to anxiety among the group with higher risk perception. As individuals perceived a higher severity of COVID-19, the impact of their financial status on anxiety increased. These findings provide a valuable resource for local governments seeking to refine their pandemic strategies by including approaches such as advocating healthy lifestyles and stabilizing the job market to improve individuals' mental health during lockdowns.
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COVID-19 , Humanos , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Ansiedade/epidemiologia , Estilo de Vida , PercepçãoRESUMO
Global production fragmentation generates indirect socioeconomic and environmental impacts throughout its expanded supply chains. The multi-regional input-output model (MRIO) is a tool commonly used to trace the supply chain and understand spillover effects across regions, but often cannot be applied due to data unavailability, especially at the sub-national level. Here, we present MRIO tables for 2012, 2015, and 2017 for 31 provinces of mainland China in 42 economic sectors. We employ hybrid methods to construct the MRIO tables according to the available data for each year. The dataset is the consistent China MRIO table collection to reveal the evolution of regional supply chains in China's recent economic transition. The dataset illustrates the consistent evolution of China's regional supply chain and its economic structure before the 2018 US-Sino trade war. The dataset can be further applied as a benchmark in a wide range of in-depth studies of production and consumption structures across industries and regions.
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Bismuth telluride-based alloys are the best performing thermoelectric materials near room temperature. Grain size refinement and nanostructuring are the core stratagems for improving thermoelectric and mechanical properties. However, the donor-like effect induced by grain size refinement strongly restricts the thermoelectric properties especially in the vicinity of room temperature. In this study, the formation mechanism for the donor-like effect in Bi2Te3-based compounds was revealed by synthesizing five batches of polycrystalline samples. We demonstrate that the donor-like effect in Bi2Te3-based compounds is strongly related to the vacancy defects (VBiâ´ and VTe···) induced by the fracturing process and oxygen in air for the first time. The oxygen-induced donor-like effect dramatically increases the carrier concentration from 2.5 × 1019 cm-3 for the zone melting ingot and bulks sintered with powders ground under an inert atmosphere to 7.5 × 1019 cm-3, which is largely beyond the optimum carrier concentration and seriously deteriorates the thermoelectric performance. Moreover, it is found that both avoiding exposure to air and eliminating the thermal vacancy defects (VBiâ´ and VTe···) via heat treatment before exposure to air can effectively remove the donor-like effect, producing almost the same carrier concentration and Seebeck coefficient as those of the zone melting ingot for these samples. Therefore, a defect equation of oxygen-induced donor-like effect was proposed and was further explicitly corroborated by positron annihilation measurement. With the removal of donor-like effect and improved texturing via multiple hot deformation (HD) processes, a maximum power factor of 3.5 mW m-1 K-2 and a reproducible maximum ZT value of 1.01 near room temperature are achieved. This newly proposed defect equation of the oxygen-induced donor-like effect will provide a guideline for developing higher-performance V2VI3 polycrystalline materials for near-room-temperature applications.
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Although defect engineering is the core strategy to improve thermoelectric properties, there are limited methods to effectively modulate the designed defects. Herein, we demonstrate that a high ZT value of 1.36 at 775 K and a high average ZT value of 0.99 in the temperature range from 300 to 825 K are realized in Zn-containing PbTe by designing complex defects. By combining first-principles calculations and experiments, we show that Zn atoms occupy both Pb sites and interstitial sites in PbTe and couple with each other. The contraction stress induced via substitutional Zn on Pb sites alleviates the swelling stress by Zn atoms occupying the interstitial sites and promotes the solubility of interstitial Zn atoms in the structure of PbTe. The stabilization of Zn impurity as a complex defect extends the region of PbTe phase stability toward Pb0.995Zn0.02Te, while the solid solution region in the other direction of the ternary phase diagram is much smaller. The evolution of defects in PbTe was further explicitly corroborated by aberration-corrected scanning transmission electron microscopy (Cs-corrected STEM) and positron annihilation measurement. The Zn atoms compensate the Pb vacancies (VPb) and Zn interstitials (Zni) significantly improve the electron concentration, producing a high carrier mobility of 1467.7 cm2 V-1 s-1 for the Pb0.995Zn0.02Te sample. A high power factor of 4.11 mW m-1 K-2 is achieved for the Pb0.995Zn0.02Te sample at 306 K. This work provides new insights into understanding the nature and evolution of the defects in n-type PbTe as well as improving the electronic and thermal transport properties toward higher thermoelectric performance.
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Urban greenspace, which serves as a place for residents to connect with nature and relax, provides important ecosystem services. Access to greenspace is often related to the socio-economic characteristics of residents, which received a lot attention from researchers and practitioners. Previous studies have mostly focused on single city to analyze the spatial relationship between greenspace distribution and residents' characteristics. We conducted a meta-analysis with global studies. The objectives were to classify findings from different cases and investigate the impacts from the location of research area, indicator and analytical method, and summarized major factors influen-cing the relationship between greenspace distribution and residents' characteristics. The results showed that more than half of the cases (58.2%) found that the socially advantaged population benefited more from greenspace. About a quarter cases (25.4%) revealed the opposite, that was, the disadvantaged population benefited more from greenspace. The remaining case studies (16.4%) did not find significant correlation between them. The studies reviewed here were diverse in terms of scale, indicator selection, and analytical method. Overall, we found no connection between finding and the choice of scale/indicator/analytical method. The reviewed case studies were mostly conducted in cities of western countries, which differed in their development trajectories and urban characteristics from cities in China. To understand association between urban greenspace and residents' characteristics in China, we urged to carry out more local studies, which would potentially provide scientific evidence for building sustainable cities during rapid urbanization.
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Ecossistema , Urbanização , China , Cidades , Fatores Socioeconômicos , População UrbanaRESUMO
Despite the achievable high thermoelectric properties in SnSe single crystals, the poor mechanical properties and the relatively high cost of synthesis restrict the large scale commercial application of SnSe. Herein, we reported that co-doping with Na and Ag effectively improves the thermoelectric properties of polycrystalline SnSe. Temperature-dependent carrier mobility indicates that the grain boundary scattering is the dominant scattering mechanism near room temperature, giving rise to low electrical conductivity for the polycrystalline SnSe in comparison with that of the single crystal. Co-doping with Na and Ag improves the electrical conductivity of polycrystalline SnSe with a maximum value of 90.1 S cm-1 at 323 K in Na0.005Ag0.015Sn0.98Se, and the electrical conductivity of the (Na, Ag) co-doped samples is higher than that of the single doped samples over the whole temperature range (300-773 K). Considering the relatively high Seebeck coefficient of 335 µV K-1 at 673 K and the minimum thermal conductivity of 0.48 W m-1 K-1 at 773 K, Na0.005Ag0.015Sn0.98Se is observed to have the highest PF and ZT among the series of samples, with values of 0.50 mW cm-1 K-2 and 0.81 at 773 K, respectively. Its average PF and ZT are 0.43 mW cm-1 K-2 and 0.37, which is 92% and 68% higher than that of Na0.02Sn0.98Se, 40% and 43% higher than that of Ag0.02Sn0.98Se, and 304% and 277% higher than that of the previously reported SnSe, respectively.
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Pristine Cr2Se3 is a narrow-band gap semiconductor but with an inferior ZT value of 0.22 obtained at 623 K. In this paper, we improve the thermoelectric performance of the Cr2Se3 material by optimizing carrier concentration, suppressing the bipolar thermal conductivity, and reducing the lattice thermal conductivity simultaneously. First, the effect of different dopants (Nb, Ni, and Mn) on the phase composition and thermoelectric transport properties of M2 xCr2-2 xSe3 (M = Nb, Ni, and Mn; x = 0-0.02) compounds are systematically investigated. The roles of those dopants are distinct. Mn-doped samples show superior thermoelectric properties in comparison with those of other-element-doped samples. Doping with Mn significantly increases the carrier concentration, accompanied with a suppression of the intrinsic excitation and a reduction of both the bipolar thermal conductivity and the lattice thermal conductivity of Cr2Se3. To further reduce the thermal conductivity, we have synthesized Mn and S codoped Mn0.04Cr1.96Se3-3 xS3 x ( x = 0-0.1) samples. Alloying with S significantly decreases the lattice thermal conductivity and enlarges the band gap, boosting the Seebeck coefficient. The maximum ZT value of Mn0.04Cr1.96Se2.7S0.3 reaches 0.33 at 823 K. Compared with the pristine Cr2Se3 sample, the maximum ZT value is increased by 50% and the temperature corresponding to the peak value shifts toward higher temperatures by 200 K.