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For the traditional low voltage ride through control under asymmetrical faults, due to the limited control degrees of freedom, the grid-connected inverter control suffers from the problem of not being able to simultaneously realize the output current negative-sequence component suppression and the DC side voltage double-frequency fluctuation suppression. In this regard, a multiple-objective decoupling control strategy is proposed for low voltage ride through of two-stage grid-connected photovoltaic system under asymmetrical faults. The strategy sets the control objective of the inverter as the negative-sequence component suppression of the output current and gives a reference value calculation method for the inner current loop considering the inverter output current limit and reactive power output demand. The super-capacitor is connected to both ends of the DC bus capacitor through the bidirectional Buck-Boost converter to maintain its voltage stability, and the DC side voltage double-frequency fluctuation is transferred to the super-capacitor side. The simulation results show that under the proposed control strategy, the unbalance between three phases of the inverter is reduced and the output current distortion is improved. The double frequency fluctuation of the DC side voltage is reduced significantly compared with the traditional control method.

Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV), a new tickborne bandavirus identified in China in 2009 (1), and subsequently in South Korea in 2013 (2), [...]

Objective Develop a novel technique to identify an optimal number of regression units corresponding to a single risk point, while creating risk scoring systems from logistic regression-based disease predictive models. The optimal value of this hyperparameter balances simplicity and accuracy, yielding risk scores of small scale and high accuracy for patient risk stratification. Materials and Methods The proposed technique applies an adapted line search across all potential hyperparameter values. Additionally, DeLong test is integrated to ensure the selected value produces an accuracy insignificantly different from the best achievable risk score accuracy. We assessed the approach through two case studies predicting diabetic retinopathy (DR) within six months and hip fracture readmissions (HFR) within 30 days, involving cohorts of 90 400 diabetic patients and 18 065 hip fracture patients. Results Our scores achieve accuracies insignificantly different from those obtained by existing approaches, reaching AUROCs of 0.803 and 0.645 for DR and HFR predictions, respectively. Regarding the scale, our scores ranged 0-53 for DR and 0-15 for HFR, while scores produced by existing methods frequently spanned hundreds or thousands. Discussion According to the assessment, our risk scores offer simple and accurate predictions for diseases. Furthermore, our new DR score provides a competitive alternative to state-of-the-art risk scores for DR, while our HFR case study presents the first risk score for this condition. Conclusion Our technique offers a generalizable framework for crafting precise risk scores of compact scales, addressing the demand for user-friendly and effective risk stratification tool in healthcare. [ABSTRACT FROM AUTHOR]

As a functional material, polyurethane elastomers have found different applications in a variety of fields such as flexible electronics and smart coatings, but due to the damage during use, they are often endowed with self‐healing properties. However, conventional intrinsically self‐healing polyurethanes often don't balance excellent mechanical and self‐healing properties, so it has become crucial to prepare polyurethane elastomers with excellent self‐healing properties and high mechanical properties. In this study, a self‐healing waterborne polyurethane elastomers (IP‐DTDAx‐BAy‐WPU‐n) was synthesized based on 4, 4‐diaminodiphenyl sulfide (DTDA) boronic acid (BA). The disulfide bond has high motility at low temperatures and induces molecular‐level healing at the damaged interface, contributing to good repair under mild conditions. The borate ester bond limits intermolecular chain slippage and improves the mechanical properties as a dynamic cross‐linking point, while its dynamic reversible effect can synergistically improve the self‐healing ability. The results show that the synthesized elastomer films have good mechanical properties (strength 23.21 MPa, elongation at break 1259.08%, toughness 83.28 MJ m−3), good elastic recovery and self‐healing properties (93%). Furthermore, a composite conductors (IP‐DTDAx‐BAy‐WPU/AgNWs) with self‐healing properties was prepared by compositing AgNWs nanowires with polyurethane elastomers, which laid the foundation for its application in flexible electronic devices and wearable sensing devices. [ABSTRACT FROM AUTHOR]

Fault structures can cause a bad mining environment and increase the stress of surrounding coal pillar faults. The study investigates the stress evolution characteristics within fault structure groups and their surrounding coal pillars and explores the extent to which these fault structure groups influence the stress distribution in coal pillars. Based on three-dimensional modeling technology, a transparent geological model of the geological environment of fault structure groups was constructed and finite difference software was used to generate a numerical simulation model. Two survey lines and four survey points were arranged to analyze the stress distribution of a coal pillar fault. The results show that the fault structure groups have obvious stress barrier effects. There is a 35 m stress reduction zone in the hanging wall of the fault and a 30 m stress increase zone in the footwall of the fault. Both FL-1 and FL-3 faults have a stress barrier effect in the hanging wall. The obvious stress increases in the footwall of the fault are 37.7 MPa and 33.5 MPa, respectively. The stress of the FL-2 fault as a whole appears to be a more obvious superposition at the end of mining, and the peak stress reaches 41.5 MPa. [ABSTRACT FROM AUTHOR]

This article discusses the potential role of the brown dog tick, Rhipicephalus sanguineus, in the transmission of severe fever with thrombocytopenia syndrome virus (SFTSV) in Hainan Island, China. The study found that SFTSV RNA levels increased in female ticks after injection with the virus, and the virus was detected in the eggs and larvae that originated from the infected female ticks. These findings suggest that R. sanguineus may serve as a vector for SFTSV and transmit the virus through transovarial transmission. Further research is needed to fully understand the vector role of R. sanguineus in SFTSV transmission. [Extracted from the article]

Ticks are hematophagous arthropods and obligate ectoparasites of humans and other animals. This study focused on the molecular discrimination of ticks in the tropical environment of Hainan according to multi-gene DNA barcode markers with the expectation of accurately distinguishing species. A total of 420 ticks, including 49 adult ticks, 203 nymphal ticks, and 168 larval ticks, were collected in the field, and the 49 adult ticks were identified as Rhipicephalus turanicus, Dermacentor marginatus, and Haemaphysalis longicornis. The mitochondrial 16S rRNA, ribosomal 28S rRNA D2, and ribosomal internal transcribed spacer 2 (ITS2) regions were used as DNA barcode markers to discriminate species. According to basic local alignment search tool analysis against the GenBank database, 16S rRNA positively identified ticks in the Rhipicephalus, Dermacentor, and Haemaphysalis genera; the 28S rRNA D2 region identified ticks in the Rhipicephalus and Dermacentor genera; and ITS2 identified ticks as D. marginatus. Pairwise sequence comparisons based on these three regions were visualized with a Sequence Demarcation Tool matrix. Substitution saturation tests using data analysis and molecular biology and evolution revealed little substitution saturation (Iss < Iss.c, p < 0.05) in the 16S rRNA region for the Haemaphysalis genus; 28S rRNA D2 region for the Rhipicephalus, Dermacentor, and Haemaphysalis genera; and ITS2 region for the Rhipicephalus and Dermacentor genera. Distinctive sequences for which it is difficult to obtain good matches with the sequences available in GenBank exist in the ticks of Hainan. Future studies should obtain complementary sequences to refine and update the database for the molecular characterization of ticks. [ABSTRACT FROM AUTHOR]

Cliques and their generalizations are frequently used to model "tightly knit" clusters in graphs and identifying such clusters is a popular technique used in graph-based data mining. One such model is the s-club, which is a vertex subset that induces a subgraph of diameter at most s. This model has found use in a variety of fields because low-diameter clusters have practical significance in many applications. As this property is not hereditary on vertex-induced subgraphs, the diameter of a subgraph could increase upon the removal of some vertices and the subgraph could even become disconnected. For example, star graphs have diameter two but can be disconnected by removing the central vertex. The pursuit of a fault-tolerant extension of the s-club model has spawned two variants that we study in this article: robust s-clubs and hereditary s-clubs. We analyze the complexity of the verification and optimization problems associated with these variants. Then, we propose cut-like integer programming formulations for both variants whenever possible and investigate the separation complexity of the cut-like constraints. We demonstrate through our extensive computational experiments that the algorithmic ideas we introduce enable us to solve the problems to optimality on benchmark instances with several thousand vertices. This work lays the foundations for effective mathematical programming approaches for finding fault-tolerant s-clubs in large-scale networks. History: Accepted by David Alderson, Area Editor for Network Optimization: Algorithms & Applications. Funding: The computing for this project was performed at the High Performance Computing Center at Oklahoma State University supported in part through the National Science Foundation [Grant OAC-1531128]. This material is based upon work supported by the National Science Foundation under [Grants 1662757 and 1942065]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/ijoc.2022.1231. [ABSTRACT FROM AUTHOR]

Least absolute deviation is proposed as a robust estimator to solve the problem when the error has an asymmetric heavy-tailed distribution or outliers. In order to be insensitive to the above situation and select the truly important variables from a large number of predictors in the linear regression, this paper introduces a two-stage variable selection method named relaxed lad lasso, which enables the model to obtain robust sparse solutions in the presence of outliers or heavy-tailed errors by combining least absolute deviation with relaxed lasso. Compared with lasso, this method is not only immune to the rapid growth of noise variables but also maintains a better convergence rate, which is O p n − 1 / 2 . In addition, we prove that the relaxed lad lasso estimator has the property of consistency at large samples; that is, the model selects the number of important variables with a high probability of convergence to one. Through the simulation and empirical results, we further verify the outstanding performance of relaxed lad lasso in terms of prediction accuracy and the correct selection of informative variables under the heavy-tailed distribution. [ABSTRACT FROM AUTHOR]

Surfactin from Bacillus amyloliquefaciens fmb50 was utilized to treat mice with type 2 diabetes (T2DM) induced by a high-fat diet/streptozotocin (HFD/STZ). Our group's earlier research indicated that surfactin could lower blood glucose and mitigate liver dysfunction to further improve HFD/STZ-induced T2DM through modulating intestinal microbiota. Thus, we further investigated the effects of surfactin on the pancreas and colon in mice with T2DM to elucidate the detailed mechanism. In the present study, mice with HFD/STZ-induced T2DM had their pancreatic and colon inflammation, oxidative stress, and endoplasmic reticulum stress (ERS) reduced when given oral surfactin at a dose of 80 mg/kg body weight. According to further research, surfactin also improved glucose metabolism by activating the phosphatidylinositol kinase (PI3K)/protein kinase B (Akt) signaling pathway, further protecting islets β-cell, promoting insulin secretion, inhibiting glucagon release and mitigating pancreas dysfunction. Additionally, after surfactin treatment, the colon levels of the tight junction proteins Occludin and Claudin-1 of T2DM mice were considerably increased by 130.64% and by 36.40%, respectively. These findings revealed that surfactin not only ameliorated HFD/STZ-induced pancreas inflammation and dysfunction and preserved intestinal barrier dysfunction and gut microbiota homeostasis but also enhanced insulin sensitivity and glucose homeostasis in T2DM mice. Finally, in the further experiment, we were able to demonstrate that early surfactin intervention might delay the development of T2DM caused by HFD/STZ, according to critical biochemical parameters in serum. [ABSTRACT FROM AUTHOR]

Surfactin, an antibacterial lipopeptide produced by different strains of Bacillus subtilis, is a powerful biosurfactant. It also has multiple biological activities including antiviral, anti-mycoplasma and antiprotozoal activities, in addition to the broad-spectrum antimicrobial activities against Gram-positive bacteria, Gram-negative bacteria and fungi. Surfactin may be one of the promising alternatives to antibiotics. Surfactin's chemical structure and physicochemical properties are briefly discussed in this mini-review. Surfactin's antibacterial mechanism is mainly outlined as follows: (1) attacking pathogenic bacteria's cell membrane, causing cell membrane disintegration or osmotic pressure imbalance; (2) inhibiting pathogenic bacteria's protein synthesis, preventing cell reproduction; (3) inhibiting pathogenic bacteria's enzyme activity, affecting normal cell metabolism. This provides basis for the further research and application of surfactin. Finally, the application of surfactin in food and its prospect are summarized in brief. [ABSTRACT FROM AUTHOR]

This article introduces a novel two-stage variable selection method to solve the common asymmetry problem between the response variable and its influencing factors. In practical applications, we cannot correctly extract important factors from a large amount of complex and redundant data. However, the proposed method based on the relaxed lasso and the adaptive lasso, namely, the relaxed adaptive lasso, can achieve information symmetry because the variables it selects contain all the important information about the response variables. The goal of this paper is to preserve the relaxed lasso's superior variable selection speed while imposing varying penalties on different coefficients. Additionally, the proposed method enjoys favorable asymptotic properties, that is, consistency with a fast rate of convergence with O p n − 1 . The simulation demonstrates that the proper variable recovery, i.e., the number of significant variables selected, and prediction accuracy of the relaxed adaptive lasso in a limited sample is superior to the regular lasso, relaxed lasso and adaptive lasso estimators. [ABSTRACT FROM AUTHOR]

Objective To assess the effect of the change from the 5-year system of coursework to a 4-year system on the achievements of medical laboratory undergraduates. Methods We analyzed and then compared the topics of training and the test scores among all subject individuals in the 5-year vs the 4-year undergraduate program. Results Five-year-program undergraduates and 4-year-program undergraduates were required to complete 50 courses. The average weekly education time in the 4-year program (27.05 lesson-hours/week) was greater than that in the 5-year program (22.99 lesson-hours/week). The proportion of clinical practice in the hospital setting in the 4-year program (26.8%) was higher than that in the 5-year program (24.5%). The average, excellent, and good scores among 4-year-program undergraduates in general education courses, professional basic courses, professional courses, all courses, and common courses were lower than those scores among the 5-year-program undergraduates. Conclusions The 5-year undergraduate program should be adapted to help boost the achievements and practical skills among its students, in helping them adapt quickly to the new, 4-year training plan (which presented a serious challenge in our cohort). [ABSTRACT FROM AUTHOR]

The midgut microbial community composition, structure, and function of field-collected mosquitoes may provide a way to exploit microbial function for mosquito-borne disease control. However, it is unclear how adult mosquitoes acquire their microbiome, how the microbiome affects life history traits and how the microbiome influences community structure. We analyzed the composition of 501 midgut bacterial communities from field-collected adult female mosquitoes, including Aedes albopictus , Aedes galloisi , Culex pallidothorax , Culex pipiens, Culex gelidus , and Armigeres subalbatus , across eight habitats using the HiSeq 4000 system and the V3−V4 hyper-variable region of 16S rRNA gene. After quality filtering and rarefaction, a total of 1421 operational taxonomic units, belonging to 29 phyla, 44 families, and 43 genera were identified. Proteobacteria (75.67%) were the most common phylum, followed by Firmicutes (10.38%), Bacteroidetes (6.87%), Thermi (4.60%), and Actinobacteria (1.58%). The genera Rickettsiaceae (33.00%), Enterobacteriaceae (20.27%), Enterococcaceae (7.49%), Aeromonadaceae (7.00%), Thermaceae (4.52%), and Moraxellaceae (4.31%) were dominant in the samples analyzed and accounted for 76.59% of the total genera. We characterized the midgut bacterial communities of six mosquito species in Hainan province, China. The gut bacterial communities were different in composition and abundance, among locations, for all mosquito species. There were significant differences in the gut microbial composition between some species and substantial variation in the gut microbiota between individuals of the same mosquito species. There was a marked variation in different mosquito gut microbiota within the same location. These results might be useful in the identification of microbial communities that could be exploited for disease control. [ABSTRACT FROM AUTHOR]

This article provides an erratum to “Finding a maximum k-club using the k-clique formulation and canonical hypercube cuts,” published online in Optim Lett, 2015 [ABSTRACT FROM AUTHOR]

Qipanzhou Yangtse River Bridge is of long span, light and soft structure. Its design and construction are extremely sensitive to strong wind. Therefore, an automatic observation station, Qipanzhou automatic weather station, is established near the bridge to observe the characteristics of the wind at the bridge. On the basis of the wind data observed at Qipanzhou weather station and data collected from Huangshi whether station from Feb. 2011 to Jan. 2012, the mean wind speed, extreme wind speed, extreme wind speed are analyzed in details in this paper. The results indicate: 1) most of the time, the monthly average wind speed, maximum wind speed and extreme wind speed at Qipanzhou weather station are larger than Huangshi weather station; 2) As the wind speed increases, the correlation between the daily maximum wind speed at bridge and Huangshi weather station decline gradually until irrelevant; 3) the predominate wind directions at Qipanzhou weather station are converging SSE and NW, in some degree different from those at Huangshi weather station, which are E and NW and non-converging. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To explore antischitosome effects of artemether, hemin and Fe3+ on Sj LDH. Methods: Enzyme activity of rSj LDH was assayed in the standard reaction system by adding different concentration of reagents (0.00-0.10 mM artemether, 0.00-0.02 mM hemin, 0.00-0.50 mM Fe3+). Same solvents of the each reagent were used as control. Results: There was no enzyme activity inhibition observed at 0.10 mM artemther; obivious inhibition for lactate oxidation reaction and pyruvate reduction reaction were detected at 0.002 mM and 0.004 mM of hemin, respectively; comparing with that of the control (P<0.05). The relative enzymatic activity inhibitions for pyruvate reduction reaction and lactate oxidation reaction at 0.02 mM hemin were 93.48% and 100.00%, respectively, comparing with that of the control (P<0.01); both pyruvate reduction and lactate oxidation reaction were inhibited completely at 0.50 mM Fe3+, comparing with that of the control (P<0.01). Conclusions: The results implied that Sj LDH was not the direct molecular target of artemether. Hemin and Fe3+ are inhibitors of Sj LDH. [Copyright &y& Elsevier]

Grain drying is a typical heat and mass transfer process with characteristics of multivariables, long time delay and nonlinearity. Thermodynamic modeling and control have been a subject of extensive research. Fuzzy logic provides a means for converting a linguistic control strategy, based on expert knowledge, into an automatic control strategy and is suitable for such process. In this article, the thermal characteristics of the grain drying process and the key factors influencing the final moisture content of the dryer are analyzed. On the basis of the analysis, an on-line measurement and fuzzy control scheme of the grain dryer are proposed. Finally, an on-line measurement and intelligent control software is developed and put into industrial application in a grain dryer. The practical control results show that the on-line measurement and intelligent control system of the dryer product satisfying control performance. [ABSTRACT FROM AUTHOR]

Examines the unsteady velocity between rotors of a counter-rotating axial fan using calibration technique. Use of nonlinear optimization of Levenberg-Marguardt method; Calculation of velocity field; Influence of temperature change in the process of calibration.

Highlights • We assessed temporal variation of soil infiltration and Manning's roughness. • High yearly variability existed for irrigation water movement and irrigation performance. • Inflow rate and cut-off ratio were optimized considering yearly variation of infiltration and roughness. Abstract Soil infiltration and Manning's roughness values are key parameters to determine the performance of surface irrigation. However, temporal variability in these parameters due to tillage practices, irrigation, and crop growth greatly hinders efforts to improve irrigation quality. The objective of this experiment was to evaluate effects of infiltration and surface roughness variation on irrigation water movement and irrigation performance indicators for border irrigation with three border lengths. Field experiments were conducted from 2013 to 2015 in a wheat (Triticum aestivum)-maize (Zea mays L.) rotation planting system at the Jinghui Canal Irrigation Area in Guanzhong Plain of northwest China. In this work, Manning's equation and a surface irrigation simulation model (WinSRFR) were used to estimate Manning's roughness values and Kostiakov soil infiltration parameters. We determined that both parameters reached moderate levels of variation for both deep and shallow tillage treatments. The impacts of temporal variation in soil infiltration and surface roughness on irrigation water movement and irrigation quality were then evaluated. Results showed that water advance times varied significantly while recession times varied much more, affecting irrigation water amounts at various distances along the length of the border. Irrigation performance indicators were significantly different over various irrigation seasons, especially for borders that were 235 m in length. Finally, considering these temporal variations during the two rotation cycles, combinations of inflow rate and cut-off ratio during different irrigation seasons were optimized, and high irrigation quality could be achieved for 80 m and 120 m borders, but not for 235 m borders. Water percolation amounts during the 2013–2014 and 2014–2015 growing periods were reduced by 55 mm and 107 mm for 235 m borders, 26 mm and 23 mm for 120 m borders, and 36 mm and 39 mm for 80 m borders, respectively. Therefore, utilizing optimal combinations of inflow rate and cut-off ratio and considering temporal variation in soil infiltration and Manning's roughness could maintain high water application efficiency and sustainable utilization of limited water resources. [ABSTRACT FROM AUTHOR]

Melioidosis is an infectious disease caused by Burkholderia pseudomallei , mainly found in Southeast Asia and northern Australia. In Hainan, sporadic cases were first described in 1990; since then, more cases have been identified. No systematic study has yet been done to detect the environmental source of the organism and its true extent in Hainan. This study is aimed to confirm the prevalence of B. pseudomallei in soil samples in Hainan. 1080 soil samples from 18 different counties were collected from 3 sampling points of 360 sites. They were screened for the presence of B. pseudomallei by Ashdown selective media. Suspected colonies of B. pseudomallei were confirmed by biochemical test and a specific PCR assay. 48 of 360 sites (13.3%) were positive for B. pseudomallei , including all coastal counties in Hainan Island. This study revealed the prevalence and distribution of B. pseudomallei in the soil environment in Hainan Island of southern China and may be helpful to understand the distribution of B. pseudomallei and to access its epidemiological importance. [ABSTRACT FROM AUTHOR]

• Optimal irrigation could be adjusted in variable precipitation years in Guanzhong Plain. • Maize seedling and wheat jointing stages were the sensitive phases to water deficit. • Irrigation at different crop growth stage significantly influenced N leaching and NUE. • Increasing N input led to higher WUE and lower deep percolation water. • Appropriate N rates were 140 and 240 kg N ha-1 for maize and wheat, respectively. Irrigation and nitrogen (N) fertilization play important roles in grain yield. However, amounts supplied in excess of crop demand are responsible for water and N leaching during intensive agricultural production. A three-year winter wheat (Triticum aestivum L.)-summer maize (Zea mays L.) rotation experiment involving varied irrigation and N fertilization treatments was conducted in the Jinghui Canal irrigation area of Guanzhong Plain in China. To develop a more sustainable agroecosystem taking into account crop yields, deep percolation and N leaching, the RZWQM2 model was used to simulate crop production. Various irrigation and N fertilization strategies were simulated to obtain high crop yields and to reduce water and N leaching in different precipitation years, using long-term historical weather data spanning 57 years (1961–2017). The simulated soil water and NO 3 -N content, grain yield, water and nitrogen use efficiencies (with nRMSE values ranging from 5.3–25.1 %), and the simulated crop biomass and N uptake (with RE values ranging from -16.4–18.3 %) were in good agreement with observed data. Simulated LAI values were acceptable (with RMSE ranging from 0.31 to 1.68 and index of agreement, d , ranging from 0.28 to 0.94), with the poorer simulations occurring with water and N stress. Maize seedling stage and wheat jointing stage were the phases most sensitive to water deficit, and optimal irrigation schedules could be adjusted according to variable precipitation and other climate changes. The best irrigation strategies for maize in the Guanzhong Plain were irrigation applied at the seedling stage in wet and normal years, and two irrigations applied at the seedling and jointing stages in dry years. The best irrigation strategies for wheat were two, three, and four irrigations applied in wet, normal, and dry years, respectively. Irrigation at different crop growth stages significantly influenced N leaching and nitrogen use efficiency. Increasing N input led to greater water use efficiency and less deep percolation water. Considering the interactive effects of water and N input on yield, deep percolation, and N leaching, the most appropriate N application rates in all precipitation years were 140 kg N ha-1 for maize and 240 kg N ha-1 for wheat, coupled with the recommended irrigation strategies. Improving water and N management can significantly reduce deep percolation of water and N leaching while maintaining agricultural productivity and environmental sustainability. [ABSTRACT FROM AUTHOR]