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Background: The soybean seed’s physiological maturity (R7) period is an extraordinary period for the formation of seed vigor. However, how proteins and their related metabolic pathways in seed and leaf change during seed physiological maturity is still not fully understood. Methods: In the present study, using a pair of pre-harvest seed deterioration-sensitive and -resistant soybean cultivars Ningzhen No. 1 and Xiangdou No. 3, the changes were investigated through analyzing leaf, cotyledon and embryo at the levels of protein, ultrastructure, and physiology and biochemistry. Results: Soybean cultivars with stronger photosynthetic capacity in leaf, higher nutrients accumulation and protein biosynthesis in cotyledon, as well as stronger resistant-pathogen ability and cell stability in embryo during seed physiological maturity, would produce higher vitality seeds. Conclusion: Such a study allows us to further understand the changes at protein, ultrastructure, and physiology and biochemistry levels in developing seeds during the physiological maturity and provide a theoretical basis for cultivating soybean cultivars with higher seed vigor.

The objective of the study was to determine the physiological mechanisms of plants in response to brassinolide (BR) alleviating cold water stress on rice. In this study, physiological responses of rice to exogenous BR and cold water submergence were investigated using the chilling-tolerant cultivar Kongyu 131 (KY131) and the chilling-sensitive cultivar Kenjiandao 6 (KJD6). A total of 2 mg L−1 BR increased activities of superoxide dismutase (SOD) and peroxidase (POD) and the contents of soluble sugar, soluble protein, and chlorophyll, but decreased the malondialdehyde (MDA) content in KY131 and KJD6 under cold water stress. The observed decreases in SOD and POD activities and MDA content recovered quickly after plants were returned to irrigation with water at temperatures of about 23.0°C in 2014. Additionally, the contents of nitrogen (N), phosphorous (P), and potassium (K) were increased by BR treatment under cold water stress. Exposure to BR also raised the percentage of high effective leaf area and leaf area index at the heading stage. Furthermore, it promoted soluble sugar synthesis, increased the rate of dry matter accumulation, and enhanced the export and translocation rates of the stem-sheath. The yield in KJD6 was significantly (P≤0.01 and P≤0.05) higher than that of the control in 2013 and 2014, respectively. The effect of BR treatment on rice leaf SOD and POD activities, MDA, chlorophyll, P, and stem-sheath K contents were more significant in KJD6 than in KY131. In conclusion, exogenous BR effectively reduced the physiological and metabolic damage in rice due to cold stress at the booting stage, promoted functional recovery in plants that received irrigation with water at a normal temperature following cold stress, and mitigated the effects of cold water stress on yield. The two varieties exhibited differential responses to BR; the weaker cold-resistant variety was more sensitive to BR and displayed stronger responses to exogenous BR.

Background: Frogeye leaf spot (FLS) is a destructive fungal disease in soybean production. The most economical and effective strategy to control FLS is to use resistant cultivars. However, the use of a limited number of resistant loci in FLS management will be countered by the emergence of new, and more virulent, Cercospora sojina races. Thus, we identified quantitative trait loci (QTL) that control resistance to FLS and identified novel resistant genes using a genome-wide association study (GWAS) on 234 Chinese soybean cultivars.Results: A total of 30,890 single nucleotide polymorphism (SNP) markers were used to estimate linkage disequilibrium (LD) and population structure. The GWAS results identified six loci (pGlyma20g31630 encoding pyruvate dehydrogenase (PDH), Glyma05g28980 encoding mitogen-activated protein kinase 7 (MPK7), and Glyma20g31510, Glyma20g31520 encoding the calcium-dependent protein kinase 4(CDPK4) in the haplotype blocks were found to be associated with FLS resistance.Conclusions: The proteins encoded by these four genes directly, or indirectly participate in the biological pathway of salicylic acid (SA) and jasmonic acid (JA). These two plant hormones can induce the expression of disease resistance related genes and are essential for plant systemic acquired resistance (SAR). Therefore, the novel loci and candidate genes provide genomic location information for further advances in FLS resistance gene cloning and molecular breeding.

Based on the average Reynolds’ equation of hydrodynamic lubrication, the axis locus and the minimum oil film thickness of the journal bearings under the dynamic load were numerically solved in this paper, and the movement and bearing characteristics of the compressor bearings at different rotation speeds were analyzed to evaluate the influence of the friction loss of the journal bearings on the performance of the rotary compressor. The simulation results indicated that the minimum oil film thickness of the sub bearing is smaller than the critical oil film thickness at low rotation speed (n ≤ 1800 rpm), therefore, the friction power increases significantly with the decrease of rotation speed. The effects of width-diameter ratio, clearance and viscosity of lubricating oil on the improvement of minimum oil film thickness were further analyzed. By optimizing the width-diameter ratio of the bearing, the load carrying capacity of the oil film is improved, and the friction power of sub bearing reduces by more than 80%. The experimental results showed that the performance of rotary compressor can be improved by more than 1% at low rotation speed.

Background Cercospora sojina is a fungal pathogen that causes frogeye leaf spot in soybean-producing regions, leading to severe yield losses worldwide. It exhibits variations in virulence due to race differentiation between strains. However, the candidate virulence-related genes are unknown because the infection process is slow, making it difficult to collect transcriptome samples. Results In this study, virulence-related differentially expressed genes (DEGs) were obtained from the highly virulent Race 15 strain and mildly virulent Race1 strain under nitrogen starvation stress, which mimics the physiology of the pathogen during infection. Weighted gene co-expression network analysis (WGCNA) was then used to find co-expressed gene modules and assess the relationship between gene networks and phenotypes. Upon comparison of the transcriptomic differences in virulence between the strains, a total of 378 and 124 DEGs were upregulated, while 294 and 220 were downregulated in Race 1 and Race 15, respectively. Annotation of these DEGs revealed that many were associated with virulence differences, including scytalone dehydratase, 1,3,8-trihydroxynaphthalene reductase, and β-1,3-glucanase. In addition, two modules highly correlated with the highly virulent strain Race 15 and 36 virulence-related DEGs were found to contain mostly β-1,4-glucanase, β-1,4-xylanas, and cellobiose dehydrogenase. Conclusions These important nitrogen starvation-responsive DEGs are frequently involved in the synthesis of melanin, polyphosphate storage in the vacuole, lignocellulose degradation, and cellulose degradation during fungal development and differentiation. Transcriptome analysis indicated unique gene expression patterns, providing further insight into pathogenesis.

Background: Since December 2019, there had been an outbreak of COVID-19 in Wuhan, China. At present, diagnosis COVID-19 were based on real-time RT-PCR, which have to be performed in biosafe laboratory and is unsatisfactory for suspect case screening. Therefore, there is an urgent need for rapid diagnostic test for COVID-19. Objective: To evaluate the diagnostic performance and clinical utility of the colloidal gold immunochromatography assay for SARS-Cov-2 specific IgM/IgG anti-body detection in suspected COVID-19 cases. Methods: In the prospective cohort, 150 patients with fever or respiratory symptoms were enrolled in Taizhou Public Health Medical Center, Taizhou Hospital, Zhejiang province, China, between January 20 to February 2, 2020. All patients were tested by the colloidal gold immunochromatography assay for COVID-19. At least two samples of each patient were collected for RT-PCR assay analysis, and the PCR results were performed as the reference standard of diagnosis. Meanwhile 26 heathy blood donor were recruited. The sensitivity and specificity of the immunochromatography assay test were evaluated. Subgroup analysis were performed with respect to age, sex, period from symptom onset and clinical severity. Results: The immunochromatography assay test had 69 positive result in the 97 PCR-positive cases, achieving sensitivity 71.1% [95% CI 0.609-0.797], and had 2 positive result in the 53 PCR-negative cases, achieving specificity 96.2% [95% CI 0.859-0.993]. In 26 healthy donor blood samples, the immunochromatography assay had 0 positive result. In subgroup analysis, the sensitivity was significantly higher in patients with symptoms more than 14 days 95.2% [95% CI 0.741-0.998] and patients with severe clinical condition 86.0% [95% CI 0.640-0.970]. Conclusions: The colloidal gold immunochromatography assay for SARS-Cov-2 specific IgM/IgG anti-body had 71.1% sensitivity and 96.2% specificity in this population, showing the potential for a useful rapid diagnosis test for COVID-19. Further investigations should be done to evaluate this assay in variety of clinical settings and populations.

In this paper, we propose a clothes classification method, an application of the gcForest. The gcForest, a novel decision tree ensemble method proposed by Zhou and Feng, performs excellently in many experiments. Moreover, we come up with some adjustment approaches for gcForest. Using these adjustment approaches, we get a satisfactory result when gcForest is used for clothes classification task. Furthermore, we create a data set for clothes classification which contains 8 categories of clothes including a total of 52000 images. And we preprocess the images in the data set by GrabCut-based clothes extraction algorithm.

Capture of uncooperative targets using tether-net systems has obvious advantages comparing with traditional rigid capture modes, while the control of such a high flexible plant is tricky. This paper mainly focuses on libraton and vibration attenuation control of the deployment process of a long distance tether-net system. A lumped mass model is built to study the elastic dynamics of the tether system. The deployment control problem is formed as a multi-constrained nonlinear optimal control problem. Piecewise control parameterization and enhancing transformation are performed, which convert the problem into a nonlinear programming problem that can be efficiently solved by the optimal control software package, MISER 3.2. The resulted control law can be easily performed by deployment speed control which requires simple mechanism and no fuel consumption. A compound control frame using tether tension and jet thrusts is proposed to realize exact positioning of the net-capture system in the terminal phase. A robust parametric approach based on eigenstructure assignment is used to design the stabilizing controller. Simulation results based on the lumped mass model show that the proposed control method can effectively attenuate the libration and vibration of the tether system during deployment and realize exact positioning of the terminal net-capture system.

The coexistence curves of (N,N-dimethylacetamide + hexane) have been determined within 10 K from the critical temperature by measurements of refractive index. The critical exponent β deduced from (T, n), (T, x), and (T, φ) curves are consistent with theoretical predictions. The results also have been analysed to obtain critical amplitudes and Wegner-correction terms when β is fixed at the theoretical value and to compare the goodnesses of fit of the diameters of coexistence curves with τ1-α and τ2β; {τ = (Tc-T)/Tc}. It has been shown that the first Wegner-correction term is just significant and volume fraction possibly is a better order parameter than is mole fraction.