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• The electron density in the D region obtained by Kunming (25.6N,103.8E) MF radar is used in this study. • The strong positive correlation of electron density in the D region with solar activity. • A empirical model of D region is established based on the correlation between D ionosphere and F107. The electron density (N e) in the D region, although its value is much smaller than that in the F region, has a highly important effect on electromagnetic wave propagation by energy absorption due to high-frequency collisions between electron-molecular, electron-ionic, molecular-ionic and so on. Solar activity is the main source of ionization in the D region of the ionosphere. The observed N e during 2008–2015 by the Kunming station (25.6°N, 103.8°E) medium radar (MF radar) is utilized to analyze its strong relationship with solar activity. Then, the relationship between them is employed to establish an empirical model in this study. The N e in the D region is enhanced with increasing height and time towards noon, and the solar zenith angle is increasingly smaller towards noon. The averages of N e at several heights below and above 76 km show that the D region ionosphere up to 76 km is more strongly controlled by solar radiation and less strongly controlled below 76 km. According to the above, an empirical model is established based on the relationship between the D-region ionosphere and solar activity index F 107. [ABSTRACT FROM AUTHOR]

Introduction: Studies have reported sex and race/ethnicity disparities in sedentary time (ST), but none have evaluated ST by well-defined periods of the weekday (before school, during school, afterschool, and evening) and weekend day (morning, afternoon, and evening). Comparing sex and race/ethnicity disparities in ST at different periods of a weekday and weekend day can deepen our understanding of disparities and inform intervention efforts. This study tests sex and race/ethnicity disparities in ST by period of day in a representative sample of US youth. Methods: Youth (N = 2,972) from the 2003–2006 NHANES waves reported demographic variables and wore an accelerometer for 7 consecutive days to assess ST. Linear regressions were conducted to test relationships between sex and race/ethnicity and ST (min/hour) during each period of a weekday and weekend day. ST differences by sex and race/ethnicity were calculated to identify the periods of the day presenting the largest opportunity to reduce disparities. Results: Females were more sedentary than males during school (p < 0∙0001), afterschool (p < 0∙0001), and weekday evenings (p < 0∙0001) after controlling for covariates. After controlling for covariates, race/ethnicity only was a significant predictor of ST during weekend mornings (p < 0∙0001). During school and afterschool emerged as the periods with the largest opportunities to reduce sex disparities in ST. Weekend mornings were identified as the largest opportunity to reduce race/ethnic disparities in ST. Conclusions: Sex disparities in ST appear to be driven mostly by the during school period of the day, while race/ethnic disparities in ST seem to be driven by the weekend morning period. Future intervention work should consider these periods when aiming to reduce ST disparities in youth. [ABSTRACT FROM AUTHOR]

Background—Despite global efforts to control tobacco use, smoking remains a leading cause of preventable diseases, mortality, and disparities, especially among individuals with mental health conditions. Smartphone apps have emerged as cost-effective tools to aid smokers in quitting; however, their evidence-based foundation remains understudied. This research conducted two searches to identify relevant apps: one through the scientific literature and the other from app stores. Methods—The study sought apps designed to assist smokers with mental health conditions in quitting. Searches were conducted in the scientific literature and major app stores. The apps found were evaluated for their basis in theory, features, and claimed effectiveness. Usage and rating scores were compared. Results—Among 23 apps found from app store search, only 10 (43%) were evidence-based and none had explicit reference to theory, while all apps identified in the literature were developed by applying theory. However, app store apps had significantly higher user numbers and ratings than those identified in the literature (mean rating 4.7 out of 5.0). Conclusion—Smokers with mental health conditions have limited support from currently available smoking cessation apps. Apps identified in the scientific literature lack sufficient use and longevity. Sustained support beyond research projects is crucial for enabling theoretically informed evidence-based apps to be available for people with mental health conditions, as is greater collaboration between developers and researchers to create apps that engage with end-user design. [ABSTRACT FROM AUTHOR]

Gravity wave (GW) activities play a prominent role in the complex coupling process of wave–wave and wave–background circulation around mid-low-latitude and equatorial areas. The wavelengths are wide, from about 10 m to 100 km, with a period from minutes to hours. However, the oscillations of GW activities are apparently different between the period bands of 0.1 to 1 h (HF) and 1 to 5 h (LF). To further understand the characteristics of GW activities, the neutral winds during 2008–2009 with a resolution of 3 min obtained from a medium-frequency (MF) radar in Kunming (25.6° N, 103.8° E) were analyzed. Using two numerical filters, the HF and LF GWs were estimated. Interestingly, the power spectral density grows larger as the frequency increases. It linearly falls with decreasing frequency when the period is less than 2 h. The seasonal variations in both HF and LF GWs are strongly demonstrated in August–September, November, and February–March with maximum meridional variances of 1100 m2 s−2 and 500 m2 s−2 and maximum zonal variances of 800 m2 s−2 and 350 m2 s−2 in, respectively. The turbulent velocity was also calculated and shows similar oscillations with GW activities. Furthermore, the GW propagation direction exhibits strong seasonal variations, which may be dependent on the location of the motivating source and background wind. [ABSTRACT FROM AUTHOR]

Photocatalytic reactions for fuel generation are crucial for the world's energy needs. Covalent‐Organic‐Frameworks (COFs) have been extensively studied as promising designable photocatalysts for these reactions due to their efficient visible‐light absorption, suitable energy‐band structure, facilitated intramolecular charge separation, and fast mass transfer. However, the activities of pristine COFs remain unsatisfactory, due to intermolecular charge recombination. Recently, COF‐based heterostructures, which combine COFs with metal‐sulfides, metal‐oxides, carbon materials, or MOFs, have attracted increasing attention for enhancing solar‐to‐fuel conversion efficiency by facilitating interfacial photo‐generated carrier separation, sensitizing wide‐gap semiconductors, and promoting surface redox reactions. Thus, a review of the state‐of‐the‐art progress of COF‐based heterostructure photocatalysts in reactions such as H2 evolution, CO2 reduction, O2 evolution, H2O splitting and CO2 splitting is crucial for the design of new photocatalysts to promote solar‐to‐fuel conversion. In this review, the COF‐based heterostructures photocatalysts are highlighted based on their synthesis, properties, and reasons for enhanced activities. Moreover, design principles are raised for such photocatalysts for each fuel generation reaction, based on insights into related research. Finally, this review is concluded by proposing future trends for COF‐based heterostructures photocatalysts, with attention to the design of COFs and supports, analyzing the photocatalytic reaction dynamics, together with considering practical applications. [ABSTRACT FROM AUTHOR]

The basic (region) leucine zippers (bZIPs) are evolutionarily conserved transcription factors widely distributed in eukaryotic organisms. In plants, they are not only involved in growth and development, defense and stress responses and regulation of physiological processes but also play a pivotal role in regulating secondary metabolism. To explore the function related to the bZIP gene family in Stevia rebaudiana Bertoni, we identified 105 SrbZIP genes at the genome-wide level and classified them into 12 subfamilies using bioinformation methods. Three main classes of cis-acting elements were found in the SrbZIP promoter regions, including development-related elements, defense and stress-responsive elements and phytohormone-responsive elements. Through protein–protein interaction network of 105 SrbZIP proteins, SrbZIP proteins were mainly classified into four major categories: ABF2/ABF4/ABI5 (SrbZIP51/SrbZIP38/SrbZIP7), involved in phytohormone signaling, GBF1/GBF3/GBF4 (SrbZIP29/SrbZIP63/SrbZIP60) involved in environmental signaling, AREB3 (SrbZIP88), PAN (SrbZIP12), TGA1 (SrbZIP69), TGA4 (SrbZIP82), TGA7 (SrbZIP31), TGA9 (SrbZIP95), TGA10 (SrbZIP79) and HY5 (SrbZIP96) involved in cryptochrome signaling, and FD (SrbZIP72) promoted flowering. The transcriptomic data showed that SrbZIP genes were differentially expressed in six S. rebaudiana cultivars ('023', '110', 'B1188', '11-14', 'GP' and 'GX'). Moreover, the expression levels of selected 15 SrbZIP genes in response to light, abiotic stress (low temperature, salt and drought), phytohormones (methyl jasmonate, gibberellic acid and salicylic acid) treatment and in different tissues were analyzed utilizing qRT-PCR. Some SrbZIP genes were further identified to be highly induced by factors affecting glycoside synthesis. Among them, three SrbZIP genes (SrbZIP54, SrbZIP63 and SrbZIP32) were predicted to be related to stress-responsive terpenoid synthesis in S. rebaudiana. The protein–protein interaction network expanded the potential functions of SrbZIP genes. This study firstly provided the comprehensive genome-wide report of the SrbZIP gene family, laying a foundation for further research on the evolution, function and regulatory role of the bZIP gene family in terpenoid synthesis in S. rebaudiana. [ABSTRACT FROM AUTHOR]

This research introduces the fully and partially exploratory factor analysis (EFA) with bi-level Bayesian regularization. The proposed models enable factor selection with a sparse model by conceptualizing the factor and loading as the group and individual levels, respectively. They offer a series of benefits such as factor extraction and parameter estimation in one step, simultaneous estimation of the model and tuning parameters, and the availability of interval estimates. Moreover, partial knowledge can be incorporated together with unknown number of factors in the partially EFA. Simulation studies and real-data analyses demonstrated that both models performed satisfactorily under reasonable conditions and were robust to interference of local dependence, while the partially EFA with appropriate information can outperform the fully version and work well under more extreme conditions. The proposed models have been implemented in the R package LAWBL. [ABSTRACT FROM AUTHOR]

In the present study, a magnetic flower-like Fe3O4@C-dot@MnO2 nanocomposite was synthesized by hydrothermal method and applied for As(III) removal by oxidation and adsorption process. Individual property of the entire material (i.e. magnetic property of Fe3O4, mesoporous surface property of C-dot and oxidation property of MnO2) make the composite efficient with good adsorption capacity for As(III) adsorption. The Fe3O4@C-dot@MnO2 nanocomposite had a saturation magnetization of 26.37 emu/g and it magnetically separated within 40 s. The Fe3O4@C-dot@MnO2 nanocomposite was able to reduce the 0.5 mg/L concentration of As(III) to 0.001 mg/L in just 150 min at pH 3. Pseudo-second-order kinetic and Langmuir isotherm model agreed with experimental data. The uptake capacity of Fe3O4@C-dot@MnO2 nanocomposite was 42.68 mg/g. The anions like chloride, sulphate and nitrate did not show any effect on removal but carbonate and phosphate influenced the As(III) removal rate. Regeneration was studied with NaOH and NaClO solution and the adsorbent was used for repeated five cycles above 80% removal capacity. The XPS studies proposed that As(III) first oxidized to As(V) then adsorb on the composite surface. This study shows the potential applicability of Fe3O4@C-dot@MnO2 nanocomposite to high extent and gives a suitable path for the proficient removal of As(III) from wastewater. [ABSTRACT FROM AUTHOR]

Tropospheric correction is a crucial step for interferometric synthetic aperture radar (InSAR) monitoring of small deformation magnitude. However, most of the corrections are implemented without a rigorous evaluation of their influences on InSAR measurements. In this paper, we present three statistical metrics to evaluate the correction performance. Firstly, we propose a time series decomposition method to estimate the tropospheric noise and mitigate the bias caused by ground displacement. On this basis, we calculate the root-mean-square values of tropospheric noise to assess the general performance of tropospheric corrections. Then, we propose the use of semi-variograms with model-fitted range and sill to investigate the reduction of distance-dependent signals, and Spearman's rank correlation between phase and elevation to evaluate the mitigation of topography-correlated signals in hilly areas. The applicability and limitations were assessed on the weather model-derived corrections, a representative spatiotemporal filtering method, and the integration of the two mainstream methods. Furthermore, we notice that the persistent scatter InSAR processing resulted in two components, the primary and secondary images' contribution to the tropospheric and orbit errors. To the best of our knowledge, this paper for the first time analyzes the respective roles of the two components in the InSAR tropospheric corrections. [ABSTRACT FROM AUTHOR]

Generalized linear models often have high-dimensional nuisance parameters, as seen in applications such as testing gene-environment interactions or gene-gene interactions. In these scenarios, it is essential to test the significance of a high-dimensional subvector of the model's coefficients. Although some existing methods can tackle this problem, they often rely on the bootstrap to approximate the asymptotic distribution of the test statistic, and are thus computationally expensive. Here, we propose a computationally efficient test with a closed-form limiting distribution, which allows the parameter being tested to be either sparse or dense. We show that, under certain regularity conditions, the Type-I error of the proposed method is asymptotically correct, and we establish its power under high-dimensional alternatives. Extensive simulations demonstrate the good performance of the proposed test and its robustness when certain sparsity assumptions are violated. We also apply the proposed method to Chinese famine sample data in order to show its performance when testing the significance of gene-environment interactions. [ABSTRACT FROM AUTHOR]

Atherosclerosis (AS) is the most common inducer of cardiovascular diseases, and resveratrol (RSV) has played a protective function in the endothelial injury of AS. This study was to explore the molecular mechanism of RSV in oxidized low-density lipoprotein (ox-LDL)-mediated endothelial dysfunction. Circ_0091822, microRNA-106b-5p (miR-106b-5p) or toll-like receptor (TLR4) levels were examined using reverse transcription-quantitative polymerase chain reaction assay. Cell viability was detected via Cell Counting Kit-8 assay and angiogenesis was assessed by tube formation assay. Cell apoptosis was determined through flow cytometry. The protein analysis was conducted via western blot. Inflammatory cytokines were measured by enzyme-linked immunosorbent assay. The oxidative injury was evaluated using the commercial kits. The binding detection was performed via dual-luciferase reporter assay and RNA pull-down assay. Circ_0091822 was downregulated by RSV in ox-LDL-treated endothelial cells. RSV promoted cell viability and angiogenesis while inhibiting apoptosis, inflammation, and oxidative stress after exposure to ox-LDL. The circ_0091822 knockdown relieved the ox-LDL-induced cell damages. RSV suppressed the ox-LDL-caused endothelial dysfunction via inducing the downregulation of circ_0091822. Circ_0091822 could target miR-106b-5p, and the reversal of circ_0091822 for RSV function was achieved by sponging miR-106b-5p. Circ_0091822 absorbed miR-106b-5p to elevate the level of TLR4. RSV impeded ox-LDL-induced damages by regulating miR-106b-5p/TLR4 axis. All these findings suggested that RSV acted as an inhibitory factor in ox-LDL-induced endothelial injury via downregulating circ_0091822 to upregulate miR-106b-5p-related TLR4. [ABSTRACT FROM AUTHOR]

This research extends the partially confirmatory approach to accommodate mixed types of data and missingness in a unified framework that can address a wide range of the confirmatory-exploratory continuum in factor analysis. A mix of Bayesian adaptive and covariance Lasso procedures was developed to estimate model parameters and regularize the loading structure and local dependence simultaneously. Several model variants were offered with different constraints for identification. The less-constrained variant can achieve sufficient condition for the more-powerful variant, although loading estimates associated with local dependence can be inflated. Parameter recovery was satisfactory, but the information on local dependence was partially lost with categorical data or missingness. A real-life example illustrated how the models can be used to obtain a more discernible loading pattern and to identify items that do not measure what they are supposed to measure. The proposed methodology has been implemented in the R package LAWBL. [ABSTRACT FROM AUTHOR]

Different from traditional practice that considers factor analysis as either exploratory or confirmatory, different amounts of substantive information can be available in between the confirmatory and exploratory extremes under the partially confirmatory approach. Based on Bayesian Lasso methods, three models were recently proposed for various types of data under the new approach: the partially confirmatory factor analysis (PCFA), generalized PCFA, and partially confirmatory item response model. All models with related variants can be implemented in the R package LAWBL, which is available free of charge. This article introduces the theoretical and statistical foundation of the three models in a unified framework, including model formulation, identification, variants, and Bayesian inference and estimation with regularizations. Didactic examples covering different scenarios are employed to illustrate the implementation of the models and their variants in LAWBL step by step. Guidelines and suggestions are given to researchers and practitioners in a discussion. [ABSTRACT FROM AUTHOR]

Graph convolutional networks (GCNs) have emerged as powerful tools for learning representations of graph structured data. A recent advancement is a decoupled GCN, which separates neighborhood aggregation from feature transformation within each graph convolutional layer and yields promising results. However, our investigation on node-level operations reveals its limitations in terms of modeling capacity and scalability, which hinder effective learning of rich node representations of diverse graphs. To address these challenges, we introduce a new paradigm of decoupled GCNs, called a neighborhood convolutional graph neural network (NCGNN). The NCGNN uses a novel neighborhood aggregator to generate a feature matrix of multi-hop neighborhoods of each node before model training. This avoids training the model via the adjacency matrix, effectively controls the training cost, and enhances scalability. Additionally, the NCGNN integrates advanced feature learning components, including a dedicated convolutional neural network for rich neighborhood information extraction and a feature fusion module to seamlessly integrate the raw attributes with the extracted features. Extensive experiments validate the superiority of the NCGNN over representative graph neural networks in node classification tasks, demonstrating its effectiveness and scalability for diverse graph structures. • Reveal limitations of insufficient modeling capacity and limited scalability of decoupled graph convolutional networks. • Introduce a new paradigm of decoupled GCNs that controls the training cost. • The developed model can adaptively learn node representations of diverse graphs. • Its effectiveness is demonstrated for both homophilic and heterophilic graphs. [ABSTRACT FROM AUTHOR]

Background: Hispanic persons living in the United States (U.S.) are at higher risk of infection and death from coronavirus disease 2019 (COVID-19) compared with non-Hispanic persons. Whether this disparity exists among critically ill patients with COVID-19 is unknown. Objective: To evaluate ethnic disparities in mortality among critically ill adults with COVID-19 enrolled in the Study of the Treatment and Outcomes in Critically Ill Patients with COVID-19 (STOP-COVID). Methods: Multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units (ICU) at 67 U.S. hospitals from March 4 to May 9, 2020. Multilevel logistic regression was used to evaluate 28-day mortality across racial/ethnic groups. Results: A total of 2153 patients were included (994 [46.2%] Hispanic and 1159 [53.8%] non-Hispanic White). The median (IQR) age was 62 (51–71) years (non-Hispanic White, 66 [57–74] years; Hispanic, 56 [46–67] years), and 1462 (67.9%) were men. Compared with non-Hispanic White patients, Hispanic patients were younger; were less likely to have hypertension, chronic obstructive pulmonary disease, coronary artery disease, or heart failure; and had longer duration of symptoms prior to ICU admission. During median (IQR) follow-up of 14 (7–24) days, 785 patients (36.5%) died. In analyses adjusted for age, sex, clinical characteristics, and hospital size, Hispanic patients had higher odds of death compared with non-Hispanic White patients (OR, 1.44; 95% CI, 1.12–1.84). Conclusions: Among critically ill adults with COVID-19, Hispanic patients were more likely to die than non-Hispanic White patients, even though they were younger and had lower comorbidity burden. This finding highlights the need to provide earlier access to care to Hispanic individuals with COVID-19, especially given our finding of longer duration of symptoms prior to ICU admission among Hispanic patients. In addition, there is a critical need to address ongoing disparities in post hospital discharge care for patients with COVID-19. [ABSTRACT FROM AUTHOR]

The myeloblastosis (MYB) gene family is one of the largest families of regulators of gene expression, and its members control a variety of plant functions. Stevia glycosides (SGs) are the most important sugar substitutes and are isolated from Stevia rebaudiana. Recently, SrMYB1 was suggested to promote SG accumulation. However, few comprehensive studies are available on MYB family members associated with SG biosynthesis and stress responses in S. rebaudiana. In this study, 374 SrMYB genes from S. rebaudiana were discovered and sorted into three categories. The genomic localization and paralogs of the SrMYB genes revealed collinearity among these 374 genes on 11 chromosomes. Moreover, the protein motifs and gene structures of the SrMYB genes were determined. The cis- elements of the SrMYB promoter were involved in many aspects of plant growth and development. Moreover, RNA-seq data revealed that 35 SrMYB genes were potentially associated with SG biosynthesis in six Stevia lines ('023', '110', '11–14', 'GP', 'GX', and 'B1188') with different SG contents. qRT-PCR suggested that 20 SrMYB genes were widely expressed in various tissues; several of these genes were more highly expressed in leaves, which are the primary site of SG biosynthesis. In addition, these 20 SrMYB genes were differentially expressed in Stevia 'B1188' in response to polyethylene glycol (PEG), salinity, methyl jasmonate (MeJA), gibberellic acid (GA), salicylic acid (SA), and low-temperature stress, which are commonly used to promote SG production. Notably, the SrMYB genes Streb.3G004940.1 , Streb.6G021840.1 , Streb.11G030580.1 , and Streb.1G039250.1 were obviously upregulated by various treatments. These findings provide further insight into the roles of SrMYB genes in controlling SG production and stress responses in S. rebaudiana. [Display omitted] • Comprehensive genomic characterization of 374 SrMYB genes in Stevia rebaudiana. • Transcriptome analysis Screened 35 SrMYBs highly associated with stevia glycosides biosynthesis. • Expression analysis revealed tissue-specific and stress-responsive SrMYBs in Stevia rebaudiana. • Selected 20 SrMYBs showed diverse expression profiles in response to abiotic factors and hormones. • Four SrMYB genes strongly implicated in regulating stevia glycosides accumulation. [ABSTRACT FROM AUTHOR]

Calcium peroxide nanoparticles (nCP) as a versatile and safe solid source of hydrogen peroxide (H 2 O 2) receive substantial attention from researchers as a potential groundwater remediation reagent. In this study, we synthesized polyvinylpyrrolidone-coated calcium peroxide nanoparticles (PVP@nCP-PVP) to control the release rate of H 2 O 2 and modulate pH fluctuation simultaneously. The PVP@nCP-PVP is fully characterized and the H 2 O 2 releasing kinetics and mechanisms are investigated. The H 2 O 2 release longevity of nCP increased with the concentration of controlled release material (CRM) encapsulated shell, while the production of H 2 O 2 decreased inversely. The acidic condition is favorable for increasing H 2 O 2 production by promoting the complex decomposition of nCP. The low temperature prolonged the longevity of nCP and suppressed the competitive side reaction for producing O 2. The release of H 2 O 2 is consistent with zero-order reaction kinetics and the release of O 2 is consistent with first-order reaction kinetics. At last, different nCP composites were employed to construct a Fenton-like system for the degradation of nitrobenzene (NB). The degradation rate was raised from 57.6% by Fe (II)/nCP to 70.0% and 93.7% by Fe (II)/nCP-PVP and Fe (II)/PVP@nCP-PVP systems, respectively. These findings demonstrate that PVP@nCP-PVP has significant advantages in repairing organically contaminated groundwater. Groundwater contamination poses a great threat to human health and ecosystems. In-situ chemical oxidation (ISCO) is a widely used groundwater remediation technology. Calcium peroxide (CP) as solid hydrogen peroxide showed merits of low cost and high stability, but the further application was limited due to its violent chemical reaction and short longivity in groundwater. In this work, we prepared polyvinylpyrrolidone-coated controlled release nCP (PVP@nCP-PVP) for modulating the release of H 2 O 2. The investigation of H 2 O 2 release kinetics under various environmental conditions enhances the understanding of the inherent relationship between the H 2 O 2 release performance of controlled-release materials and contamination remediation. The feasibility using macromolecules preparing controlled-release oxidizing agents was confirmed, providing a novel solution for groundwater contamination remediation. [Display omitted] • The nCP was coated with Polyvinylpyrrolidone to achieve controlled release of H 2 O 2. • The longevity of nCP increased 55 times with Polyvinylpyrrolidone modification. • Polyvinylpyrrolidone core shell prevented pH increase of the solution. • Degradation of NB increased 1.6 times for Fe (Ⅱ)/PVP@nCP-PVP compared to Fe (Ⅱ)/nCP. • PVP@nCP-PVP acts as a stable H 2 O 2 source for contamination remediation. [ABSTRACT FROM AUTHOR]

This research proposes a one-step Bayesian regularized approach to exploratory factor analysis (EFA) with an unknown number of factors. The proposed Bayesian regularized exploratory factor analysis (BREFA) model builds on the idea of bi-level Bayesian sparse group selection and can produce exact zero estimates at both the factor and loading levels. It can distinguish true factors from spurious factors and provide estimations of model and tuning parameters simultaneously. In addition to achieving model simplicity at both the factor and item levels, the approach provides interval estimates that can be used for significance testing, making it capable of addressing both uncorrelated and correlated factors. The Bayesian hierarchical formulation is implemented using Markov chain Monte Carlo estimation with the multivariate spike and slab priors and posterior median estimator. Based on simulated and real data analysis, BREFA demonstrates clear advantages or flexibility compared with traditional and Bayesian EFA, in terms of factor extraction, parameter estimation, and model interpretation. [ABSTRACT FROM AUTHOR]

This study analyzed the Trends in International Mathematics and Science Study 2011 data on fourth-grade U.S. students' mathematics performance to answer four research questions: (a) How did U.S. students' geometry performance compare with their performance on the other mathematics subscales? (b) What were the patterns of student achievement among the mathematics subscales? (c) Was there a group of students who demonstrated specific difficulties in geometry only? and (d) Which demographic variables contributed to students' classification in the group with geometry difficulties? We found that (a) U.S. students' performance was poorer on the Geometry subscale than on other mathematics subscales; (b) using latent profile modeling, we identified a group of students with the lowest scores across all three mathematics subscales who showed a significant discrepancy between Geometry and the other subscales that did not exist within the high-achieving and average-achieving groups; and (c) gender, age, home language, race, and preference for mathematics and science significantly influenced the probability of being classified in the group with the lowest performance and the largest gap between Geometry and other mathematics subscales. Implications for educational theory and practice are discussed. [ABSTRACT FROM AUTHOR]

Minimum-cost flow problems widely exist in graph theory, computer science, information science, and transportation science. The network simplex algorithm is a fast and frequently used method for solving minimum-cost flow problems. However, the conventional sequential algorithms cannot satisfy the requirement of high-computational efficiency for large-scale networks. Parallel computing has resulted in numerous significant advances in science and technology over the past decades and is potential to develop an effective means to solve the computational bottleneck problem of large-scale networks. This paper first analyzes the parallelizability of network simplex algorithm and then presents a multi-granularity parallel network simplex algorithm (MPNSA) with fine- and coarse-granularity parallel strategies, which are suitable for shared- and distributed-memory parallel applications, respectively. MPNSA is achieved by message-passing interface, open multiprocessing, and compute unified device architecture, so that it can be compatible with different high-performance computing platforms. Experimental results demonstrated that MPNSA has very great accelerating effects and the maximum speedup reaches 18.7. [ABSTRACT FROM AUTHOR]

The effect of temperature on the diffusivity and mechanical property of the TiAl/Ti3Al interface at nanoscale was investigated using molecular dynamics (MD). The diffusion mechanism is atomic self-diffusion in the TiAl or Ti3Al blocks at the temperatures of 673 ~ 1273 K. However, self-diffusion and asymmetric counter-diffusion determine the diffusion process. The self-diffusion of atoms in the Ti3Al block is much better than that in the TiAl block under the same temperature. The average atomic diffusive distance in the TiAl block is significantly farther than that in the Ti3Al block owing to its lower melting point and greater numbers of slipping system. The yield strength of the joint after diffusion welding at the temperatures of 673 ~ 1373 K is about 1.2 GPa higher than that at 1473 K. The temperature has little effect on the mechanical properties of elastic modulus, yield strength, yield strain and flow stress of the diffusion joint at the temperatures of 673 ~ 1273 K. However, the elastic modulus, yield strength and flow stress decrease gradually with the increase in temperature at 1273 ~ 1473 K. [ABSTRACT FROM AUTHOR]

BACKGROUND: Although desired cartilage repair has been realized via tissue engineering technology, these achievements mainly focus on small-size defect under a normal physical condition. However, cartilage defects are always accompanied by the underlying diseases in clinical practice, such as osteoarthritis and rheumatoid arthritis. Meanwhile, the location, scope, and depth of cartilage defects are uncertain, which brings a great challenge in cartilage tissue repair. OBJECTlVE: To summarize the methods of repairing articular cartilage defects at different locations and under inflammatory condition. METHODS: We searched PubMed and CNKI with the search terms "cartilage defect regeneration, osteochondral, growth plate, weight-bearing area, inflammatory" in Chiense and English to retrieve related papers published before March 2019. A total of 209 papers were retrieved and 86 were included in the final analysis according to inclusion and exclusion criteria. RESULTS AND CONCLUSION: For articular cartilage defects under different special conditions, the repair goals and strategies are different. For repair of full-layer cartilage defects and osteochondral structure defects, multi-layered scaffolds are often used to repair the unique stratified cartilage structure and subchondral bone structure, while avoiding the problem of heterotopic ossification in neonatal cartilage. To avoid deformity after long bone maturation, growth factors such as insulin-like growth factor and bone morphogenetic protein 7 should be added to continuously stimulate the repair of the growth plate and promote bone growth. For cartilage repair in the weight-bearing area, the scaffolds should have good mechanical property, which ensure not to undergo severe deformation and structural damage when loaded. In addition, the new cartilage tissue has sufficient mechanical strength to support sustained longitudinal pressure and wear. For cartilage defects in the inflammatory state, both inflammation management and cartilage defect repair should be considered, and introduction of mesenchymal stem cells can regulate immune function and promote tissue regeneration, such that articular cartilage defect can be completely repaired. [ABSTRACT FROM AUTHOR]

MO/TiO 2 (M = Mg, Ca, Sr and Ba) composites were prepared for photocataytic aniline oxidation under visible light irradiation. The surface basicity of the photocatalysts was enhanced with the increasing atomic number of the alkaline earth metals. The aniline conversion and the product selectivity are closely related to the surface basicity of catalysts. The formation of surface complexes is a key step for the photocatalytic reaction under visible light irradiation. • Photocatalytic oxidation of aniline are achieved over MO/TiO 2 (M = Mg, Ca, Sr, Ba) under visible light irradiation. • The surface basicity and aniline conversion efficiency for the photocatalysts become higher and higher with the increasing atomic number of the alkaline earth metals. • BaO/TiO 2 with highest surface basicity facilitates the formation of azobenzene and nitrobenzene. • Surface complexes formed by aniline chemisorption play crucial roles for photocatalytic aniline oxidation under visible light irradiation. MO/TiO 2 (M = Mg, Ca, Sr & Ba; TiO 2 : Evonik Aroxide P25) composites were prepared for photocatalytic aniline oxidation under visible light irradiation. The conversion efficiencies of aniline over the samples are revealed as follow order: BaO/TiO 2 >SrO/TiO 2 >CaO/TiO 2 >MgO/TiO 2. The combined results of XPS and CO 2 TPD indicate that the electron density of lattice oxygen and the surface basicity for the photocatalysts became higher and higher with the atomic number increase of the alkaline metal elements, in accordance with the order of the conversion efficiency. The sample SrO/TiO 2 shows the highest nitrosobenzene selectivity. BaO/TiO 2 with highest surface basicity may facilitate the further aniline transformation to nitrobenzene and azobenzene, resulting in lower selectivity for nitrosobenzene. Surface complexes formed on the basic sites of the catalysts via aniline chemsorption would be acted as active sites and be excited for the photocatalytic oxidation of aniline under visible light irradiation. [ABSTRACT FROM AUTHOR]

Estimating the spatial distribution of precipitation is important for understanding ecohydrological processes at catchment scales. However, this estimation is difficult in mountainous areas because ground-based observation stations are often sparsely located and do not represent the spatial variability of precipitation. In this study, we develop a Bayesian assimilation method based on data collected on the Tibetan Plateau from 1980 to 2014 to estimate monthly and daily precipitation. To accomplish this, point-scale ground meteorological observations are combined with large-scale precipitation data such as satellite observations or reanalysis data. First, we remove the terrain effects from ground observations by fitting the precipitation data as functions of elevation, and then we spatially interpolate the residuals to 5-km-resolution grids to obtain monthly and daily precipitation. Additionally, we use Tropical Rainfall Measuring Mission (TRMM) satellite observations and ERA-Interim reanalysis data. Cross-validation methods are used to evaluate our method; the results show that our method not only captures the change in precipitation with terrain but also significantly reduces the associated uncertainty. The improvements are more evident in the main river source areas on the edge of the Tibetan Plateau, where elevation changes dramatically, and in high-altitude areas, where the ground gauges are sparse compared with those in low-altitude areas. Our assimilation method is applicable to other regions and is particularly useful for mountainous watersheds where ground meteorological stations are sparse and precipitation is considerably influenced by terrain. [ABSTRACT FROM AUTHOR]

Quantifying the gap between actual and exploitable yields (Ya and Ye, respectively) at the regional scale is critical for understanding the scope and hotspots for future yield improvements. Remote sensing can provide geospatially continuous observations of crop growth, which is perceived as an effective means to overcome the scaling issue commonly suffered by regional yield gap (YG) studies. However, the consistency and uncertainties of different modeling paradigms (i.e., model-driven or data-driven paradigm) remain to be investigated when integrating remote sensing data into YG analysis. This study provides a comprehensive assessment of process-based and machine learning approaches for estimating rice YG over Northeast China. Three machine learning models are examined for predicting Ya, the results of which reveal a prevalent deviation in the estimation of extreme yields. A rotation scheme is thereby proposed to correct this error, and the outperforming random forest model is selected to be compared with a biophysical process-based model (BEPS). County-scale validation reveals good accuracy of both the process-based and machine learning models in estimating Ya, with RMSEs of 1355.3 kg ha−1 (17.3%) and 1205.0 kg−1 (15.4%), respectively. The process-based model reproduces well the probability distribution of Ya in peaks and tails, which guarantees the reasonable estimation of Ye, given that Ye is derived from the high percentile of Ya. In contrast, the machine learning model trained over county-scale yield statistics underestimates the heterogeneity of Ya, leading to significant shrinkage of Ye and thus YG. Degraded model consistency is found from the estimation of Ya, Ye to YG, yet the discrepancy presents limited impacts on identifying the regional priorities for closing YG. The remote sensing-based estimations under the "top-down" framework are further evaluated against the results of the Global Yield Gap Atlas (GYGA), which follows a "bottom-up" protocol. Multiscale comparisons (i.e., local, subregional and regional) with the GYGA and other reference results suggest that the pixelwise modeling of crop-growing processes constitutes a more reliable approach for estimating rice YG over Northeast China, although uncertainty exists in both remote sensing approaches in the local YG estimation. The need to train machine learning models using representative datasets at the field scale is strongly emphasized. This study contributes to the first comprehensive understanding of different modeling paradigms for YG analysis and has important implications for promoting model development and ensuring food security. [Display omitted] • Use model- and data-driven approaches to assess regional yield gap (YG) with remote sensing (RS). • Degraded model consistency is found when estimating actual yield, exploitable yield, and YG. • Provide multiscale comparisons between the RS-based (top-down) and GYGA (bottom-up) protocols. • Pixelwise crop growth modelling produces more reliable YG estimates than the ML model. • Training with county-scale yield statistics diminishes the ability of ML models to estimate YG. [ABSTRACT FROM AUTHOR]

• The degradation of NB was accelerated by the reduction of S-nZVI. • The degradation of NB was influenced by both reduction and oxidation. • Oxidation contributes to the further mineralization of TOC in system. • The reduction of Fe3+ is accelerated by elemental sulfur. • Degradation pathways and Intermediates of NB were proposed. In recent years, nitrobenzene (NB) leakage has emerged as one of the most pressing environmental issues related to groundwater contamination that requires immediate attention. This study aimed to combine S-nZVI reduction with persulfate (PDS) oxidation for NB degradation in aquatic environment. The strong synergistic effect of reduction and oxidative degradation of NB in the S-nZVI/PDS system was demonstrated for the first time. To throughly investigate the mechanism of PDS activation by S-nZVI, chemical quenching tests, detection of electron spin resonance (ESR), and monitoring of oxidant consumption were conducted. According to the results, the reactive oxygen species in the reaction system originated predominantly from the presence of ≡Fe2+ on the surface of S-nZVI and from the free state of Fe2+ in the co-activation of PDS in solution. The main role of S(-II) on the surface of S-nZVI is to enhance the electron transfer ability and act as an electron donor to facilitate the conversion between Fe2+ and Fe3+. In addition, density functional theory calculations was used to reveal the reactive sites of NB and clarify the possible degradation pathways of NB. The results of this study will deepen the understanding of the mechanism of S-nZVI driven persulfate activation and provide fundimental support for the future practical application of the S-nZVI/PDS system for the remediation of nitrobenzene contaminated groundwater. [ABSTRACT FROM AUTHOR]

Abstract The complement system has important roles in both innate and adaptive host defense against invading microorganisms in vertebrates. The complement factor B (Bf), complements 2 (C2) and 4 (C4) can initiate and activate the complement system. In the present study, three complement genes, named as OnBf , OnC2 and OnC4 , were identified from Oreochromis niloticus , their distributions in host tissues and dynamic expressions after Gyrodactylus cichlidarum infection were investigated. The full-length cDNA of OnBf comprises an open reading frame (ORF) of 2055 bp, encoding a polypeptide of 684 amino acids which consists of two CCP modules at the N-domain, one VWA domain, and one Tryp_SPc domain at the C-terminal. The open reading frame (ORF) of OnC2 cDNA of 2385 bp encodes a protein of 794 amino acids with three (CCP) modules at the N-terminal, a less complex region, a VWA region, and a Tryp_SPc domain at the C-terminal. The full-length cDNA of OnC4 is comprised of an open reading frame (ORF) of 5082 bp encoding a polypeptide of 1693 amino acids which orderly includes A2M_N_2, ANATO, A2M, A2M_recep, C345C and three less complex regions. Quantitative real-time PCR (qPCR) analysis revealed that OnBf , OnC2 and OnC4 had higher levels of expression in the liver, stomach and spleen than in the tissues examined. After G. cichlidarum infection, the expression levels of OnBf , OnC2 , and OnC4 in the skin, liver, spleen and kidney were up-regulated at 2, 4, 6, 8, 10, 12 and 14 days, in general accordance with dynamics of prevalence and mean intensity, each showing an initial increase and subsequent decrease. These results might suggest that G. cichlidarum infection had induced a host immune response via OnBf , OnC2 , and OnC4. Highlights • The Bf/C2 and C4 genes were cloned and characterized from Oreochromis niloticus. • The expressions of Bf , C2 and C4 in different tissues of normal O. niloticus and those after Gyrodactylus cichlidarum infection. • After infection, the upgraded expression of immune related genes were consistent with trends of prevalence and mean intensity. • Gyrodactylus cichlidarum are preferentially located on the fins rather than on the body of Oreochromis niloticus. [ABSTRACT FROM AUTHOR]

Background/Aims: We aimed to explore the associations between clinical parameters and long-term allograft outcomes in transplant glomerulopathy (TG) in a large retrospective cohort with long follow-up. Methods: Clinical and laboratory data at biopsy from 180 cases of TG with an estimated glomerular filtration rate (eGFR)> 15ml/min/1.73m2 from January 2004 to December 2016 at our center were retrospectively analyzed. The main outcome of this study was initiation of replacement therapy or an eGFR declined to < 15 ml/min/1.73m2. Results: During a median follow-up of 5 years (interquartile range 2.6-8.2 years), 117 cases (65.0%) achieved the combined event. Kaplan-Meier method yielded the 1-year and 5-year cumulative renal allograft survival rates after a histopathologic diagnosis of TG were 84% (95% confidence interval [CI] 81-87%) and 33% (95% CI 27–39%) respectively. In univariate analysis, allograft outcome differed significantly by eGFR, proteinuria, blood hemoglobin level, urinary retinol-binding protein (urRBP) and urinary N-acetyl-β-D-glucosaminidase (urNAG) level at the time of biopsy. Multivariate Cox analysis revealed that a higher level of eGFR was the most powerful predictor of allograft survival. Compared with those with eGFR≥60, the hazard ratio (HR) increased from 4.50 (95% CI: 1.03-19.71, p=0.0462) for patients with eGFR between 30 and 59 ml/min/1.73m2 to 9.14 (95% CI 1.97-42.45, P=0.0047) when eGFR decreased to 15 to 29 ml/min/1.73m2. Additionally, proteinuria and higher urRBP values (≥2.85mg/dl) were found to confer much worse survival rates for TG patients in multivariate Cox analysis. Male sex (HR 0.48, P=0.02) and HCV infection (HR 1.78, P=0.0499) were also found to be independent risk factors for worse allograft survival. Conclusion: Five clinical features—impaired renal function, higher proteinuria, higher urRBP level, male sex and HCV infection—are independent predictors of an unfavorable renal allograft outcome. urRBP is a simple and useful parameter that can add invaluable information for the clinical follow-up of patients with TG. [ABSTRACT FROM AUTHOR]

Emerging evidence indicates that microRNAs (miRNAs) are crucial regulators of osteoblast differentiation. A previous study has reported that miR-193a-3p expression is altered during the induction of osteoblast differentiation. However, the precise biological function and regulatory mechanism of miR-193a-3p during osteoblast differentiation remains unclear. In this study, we aimed to investigate the precise role and underlying mechanism of miR-193a-3p in regulating osteoblast differentiation. The results showed that miR-193a-3p expression was significantly down-regulated during the induction of osteoblast differentiation. Functional experiments demonstrated that the overexpression of miR-193a-3p impeded osteoblast differentiation while miR-193a-3p inhibition promoted osteoblast differentiation. Bioinformatics analysis and a luciferase assay revealed that leucine-rich repeat-containing G-protein coupled receptor 4 (LGR4), a critical regulator of osteoblast differentiation, was a target gene of miR-193a-3p. We showed that miR-193a-3p negatively regulated the expression of LGR4 and activating transcription factor 4 (ATF4). Moreover, the knockdown of LGR4 or ATF4 significantly reversed the promotion effect of miR-193a-3p inhibition on osteoblast differentiation. Overall, these findings demonstrate that miR-193a-3p regulates osteoblast differentiation by modulating LGR4/ATF4 signaling and suggests that the miR-193a-3p/LGR4/ATF4 regulation axis may play an important role in regulating bone remodeling. [ABSTRACT FROM AUTHOR]

MgO/TiO 2 (Degussa P25 TiO 2 ) composites were prepared and were used as visible-light-driven photocatalysts for the oxidation of aniline to nitrosobenzene under oxygen atmosphere. The typical sample with 5 wt% MgO loaded P25 (MP5) shows comparable photocatalytic activity with 2 wt% Pt/P25. The analyzed results of XPS indicate that the lattice oxygen in the MP5 possess higher electron density than those in P25. The electron-rich lattice oxygen, formed as a result of MgO loaded, would facilitate the deprontonation of aniline. A new peak at 3310 cm −1 was observed in in-situ FTIR spectrum for aniline adsorbed on the sample MP5, suggesting that anilino species were formed. These species may be produced via the deprontonation of aniline and result in the formation of the surface complexes. Further XPS studies for aniline adsorbed on the catalysts also indicate the existence of the surface complexes. Under visible light irradiation, the electrons may excite from the surface complexes and initiate the oxidation processes. Finally, speculated photocatalytic processes for the oxidation of aniline to nitrosobenzene were proposed at molecular level. [ABSTRACT FROM AUTHOR]

Rubber expansion has been widely explored at various scales due to its increasing environmental and socio-economic impact and the global demand for natural rubber products. However, accurate and up-to-date maps and large-scale monitoring of rubber plantation spatial distribution are not yet available. In this article, we developed a simple algorithm for rapidly and accurately mapping rubber plantations on Hainan Island, China, by combining survey samples and Landsat 8 Operational Land Imager data from 2014 in order to understand their spatial distribution. The results showed that rubber plantations are distinguishable from other land-cover types by band value changes, vegetation index changes, and phenological phase changes (defoliation and foliation) and can be accurately extracted from multi-temporal Landsat images using a decision tree method and Google Earth Engine. This method results in a high overall classification accuracy of 92.17% with a correspondingκof 84.33%. Rubber plantations are concentrated in the northwest of Hainan Island and gradually decrease to the south and east. Most plantations are found in the 50–500-m elevation range, with few found outside this range. We believe that the proposed approach will have significant implications for mapping and monitoring rubber spatial distribution at regional scales. [ABSTRACT FROM PUBLISHER]

The role of resveratrol (trans‑3,5,4'‑trihydroxystilbene; RES) in lysophosphatidylcholine (LPC)‑induced injury and inflammation in endothelial cells (regarded as an early event in arteriosclerosis) is unclear. The present study investigated whether RES reduces lactate dehydrogenase (LDH) activity and secretion of inflammatory cytokines such asinterleukin‑6 and tumor necrosis factor‑α, via the Toll‑like receptor (TLR)‑4/myeloid differentiation primary response gene 88 (MyD88)/nuclear factor (NF)‑κB signal transduction pathway in LPC‑induced damage and inflammation in human umbilical vein endothelial‑12 (HUVE‑12) cells. Using an ELISA and western blotting, the present study investigated the effects of RES on LDH activity and cytokine secretion. The effects of TLR‑4 short hairpin (sh)RNA and TLR‑4 cDNA transfection on NF‑κB activation during LPC‑induced damage and inflammation was also investigated in HUVE‑12 cells. The results demonstrated that RES significantly inhibited the effect of LPC on enzyme activity, pro‑inflammatory cytokine secretion, and expression of TLR‑4, MyD88 and NF‑κBp65 expression. In addition, RES and TLR‑4 shRNA transfection suppressed LPC‑induced injury and inflammation by blocking the TLR‑4/MyD88/NF‑κB signaling pathway Conversely, transfection with TLR‑4 cDNA enhanced LPC‑induced injury and inflammation, which abrogated the protective effects of RES. These data suggested that RES significantly suppressed LPC‑induced damage and inflammation, via suppression of the TLR‑4/MyD88/NF‑κB signaling pathway, which may provide a new mechanistic evidence for the treatment of arteriosclerosis by RES. [ABSTRACT FROM AUTHOR]

Aims: As a glucagon-like peptide-1 receptor agonist, liraglutide could effectively increase insulin secretion from pancreatic β-cells and suppress glucagon secretion from pancreatic α-cells in the treatment of hyperglycemia in type 2 diabetes patients. However, the mechanisms for the different regulation of pancreatic α-cells and β-cells are still unclear. In this study, we mainly explored the different effects of liraglutide on mouse pancreatic α-cell line and β-cell line in vitro. Main methods: Herein, mouse pancreatic α-cell line, α-TC1-6, and mouse pancreatic β-cell line, β-TC-tet, were used to analyze the biological effects of liraglutide in different concentrations. Cell proliferation, cell apoptosis and cell secretion ability were detected in different groups. Besides, the level of miR-375 and cAMP-PKA signal pathway were further evaluated using qPCR and western blot. Key findings: The results indicated that liraglutide could increase the level of miR-375 and cell apoptosis in pancreatic α-cells through inhibiting the cAMP-PKA signal pathway, but activate cAMP-PKA signal pathway in pancreatic β-cells, and further lead to the down-regulation of miR-375 and improve cell viability. Therefore, the treatment with liraglutide could down-regulate the glucagon secretion ability of α-TC1-6 cells, and the insulin secretion ability of β-TC-tet cells was enhanced with the liraglutide treatment in a dose-dependent manner. Significance: In conclusion, we mainly found that liraglutide could regulate the viability of pancreatic α-cells and pancreatic β-cells through inhibiting and activating cAMP-PKA signal pathway respectively. The better understanding of the mechanism could help us to develop more novel therapy methods for diabetes in the future. [ABSTRACT FROM AUTHOR]

Although validity is acknowledged as the most fundamental consideration in psychological and educational testing, there is disagreement stemming from two different approaches: the ontological vs. the epistemological. This article introduces a flexible approach to test validity based on context-specific constructs, which can accommodate the two existing approaches conceptually. Based on the test foundation and rationale, a unique construct domain can be defined and measured by one test score given that the score meaning is valid. With the separation of the meaning and use validities and different types of score use (i.e., basic, extended, and joint), the proposed approach offers great flexibility for test validation. However, this paper only provides a skeleton for the flexible approach, and much more work is needed. [ABSTRACT FROM AUTHOR]

Gyrodactylids mainly parasitizing on the skin and fins of fishes, represent an ongoing challenge of farmed fishes. Evidences from previous studies suggested that complement system play important role in fish against gyrodactylids. Through a series of parasite killing experiments with fish sera and mucus, the present study revealed the role of Oreochromis niloticus complement in killing Gyrodactylus cichlidarum. The killing effect on G. cichlidarum was observed in serum and mucus of O. niloticus , which was markedly weakened after the complement inhibition by heat treatment and C3 antibody neutralization. Scanning electron microscopy (SEM) revealed various injuries on the tegument of G. cichlidarum exposed to O. niloticus serum. After inhibiting the alternative complement pathway (ACP) by zymosan, the killing activity of O. niloticus serum to G. cichlidarum was significantly attenuated (P < 0.01). The inhibition (by adding EGTA or l -lysine) to the classical complement activation pathway (CCP) also resulted a weak suppression on the killing effect. The results demonstrated the indispensable role of O. niloticus complement in killing G. cichlidarum , mainly via the ACP and with the involvement of CCP as well. In addition, complement in serum of an unnatural host (Ctenopharyngodon idella) of G. cichlidarum showed highly significantly weaker killing effect to G. cichlidarum than that of O. niloticus (P < 0.01), which needs further study for its mechanism. These findings provided new evidences about the immune mechanism of fish against gyrodactylids, and are reference for the study on the control of gyrodactyliasis. • The complement in serum and mucus of Oreochromis niloticus displayed strong killing effect on Gyrodactylus cichlidarum. • The killing effect was mainly mediated by ACP, and CCPwas also involved. • The complement in serum of Ctenopharyngodon idella (non-host) showed weak killing effect to Gyrodactylus cichlidarum. [ABSTRACT FROM AUTHOR]

Abstract Postmortem meat tenderization is a process mediated by a series of biochemical reactions related to muscle cell death. Cell death is considered a sign that muscle has started to transform into meat. Mitochondria play a significant role in regulating and executing cell death, as they are an aggregation point for many cell death signals and are also the primary target organelle damaged by tissue anoxia. Mitochondrial damage is likely to have an expanded role in postmortem meat tenderization. This review presents current findings on mitochondrial damage induced by the accumulation of reactive oxygen species during postmortem anaerobic metabolism and on the impact of mitochondrial damage on proteolysis and discusses how this leads to improved tenderness during aging. The underlying mechanisms of mitochondrial regulation of postmortem muscle tenderization likely focus on the mitochondria’s role in postmortem cell death and energy metabolism. The death process of postmortem skeletal muscle cells may exhibit multiple types, possibly involving transformation from autophagy to apoptosis and, ultimately, necroptosis or necrosis. Mitochondrial characteristics, especially membrane integrity and ATP-related compound levels, are closely related to the transformation of multiple types of dead postmortem muscle cells. Finally, a possible biochemical regulatory network in postmortem muscle tenderization is proposed. [ABSTRACT FROM AUTHOR]

Most psychological questionnaires face issues of response bias in respondent-reported scales, inadequacy for criterion-reference testing, or difficulty in estimating a large number of latent traits. Situational tests together with the general nominal diagnosis model framework provide a viable alternative to alleviate these concerns. Under this framework, there are different ways to design situationally nominal items, which can offer more flexibility for test development. Any response bias remaining with respondent-reported questionnaires may be addressed with appropriate test designs. The saturated model subsumes different reduced forms that can help inform whether the test is designed as expected. Two simulation studies are presented to demonstrate the effectiveness of the models and designs. [ABSTRACT FROM AUTHOR]

Q-matrix validation is of increasing concern due to the significance and subjective tendency of Q-matrix construction in the modeling process. This research proposes a residual-based approach to empirically validate Q-matrix specification based on a combination of fit measures. The approach separates Q-matrix validation into four logical steps, including the test-level evaluation, possible distinction between attribute-level and item-level misspecifications, identification of the hit item, and fit information to aid in item adjustment. Through simulation studies and real-life examples, it is shown that the misspecified items can be detected as the hit item and adjusted sequentially when the misspecification occurs at the item level or at random. Adjustment can be based on the maximum reduction of the test-level measures. When adjustment of individual items tends to be useless, attribute-level misspecification is of concern. The approach can accommodate a variety of cognitive diagnosis models (CDMs) and be extended to cover other response formats. [ABSTRACT FROM AUTHOR]

It is common to encounter polytomous and nominal responses with latent variables in social or behavior research, and a variety of polytomous and nominal item response theory (IRT) models are available for applied researchers across diverse settings. With its flexibility and scalability, the Bayesian approach using the Markov chain Monte Carlo (MCMC) method demonstrates its great advantages for polytomous and nominal IRT models. However, the potential of the Bayesian approach would not be fully realized without model formulations that can cover various models and effective fit measures for model assessment or criticism. This research first provided formulations for typical models that are representative of different modeling groups. Then, a series of discrepancy measures that can offer diagnostic information for model-data misfit were introduced. Simulation studies showed that the formulation worked as expected, and some of the fit measures were more useful than the others or across different situations. [ABSTRACT FROM AUTHOR]

Background: Definitive evidence shows sedentary time (ST) is an independent risk factor for chronic disease, irrespective of physical activity. Despite calls to limit youth ST, studies demonstrate a spike in ST at the transition from childhood to adolescence. Identifying periods of the day (e.g., before school, during school, afterschool, and evenings) during which ST is higher in adolescents vs. children-that is, specifying when within daily routines ST disparities emerge-may be important to inform intervention strategies, as periods of the day correspond with variations in setting and supervision. The purpose of this study was to examine device-assessed ST engagement by period of day and developmental stage in a nationally representative sample of United States youth.Methods: Youth (N = 2,972 between 6-18 years) from the 2003-2004 and 2005-2006 waves of NHANES reported demographic variables and wore an accelerometer for seven consecutive days to determine ST. Linear regression analyses were applied to study associations between ST and developmental stage (childhood or adolescence) by period of the week and weekend days, while controlling for sex, race/ethnicity, annual family income, and body mass index.Results: Adjusted linear regressions (p-values < 0.0001) showed that adolescents were more sedentary than children during school, afterschool, and weekday evening periods as well as all the weekend periods. However, during school (36.3 ± 7.3 vs. 28.2 ± 7.2 min/hour; b = -7.4 [-8.1, -6.6]) and afterschool periods (31.1 ± 7.7 vs. 22.7 ± 7.0 min/hour; b = -7.8 [-8.6, -7.0]) showed the largest weekly ST disparities by developmental stage. Overall, the during school and after school hours constitute most (during school = 35% and afterschool = 16%) of the weekly ST disparity between children and adolescents.Conclusions: Our data provide interventionists with estimates of the potential for ST reduction in each setting and period of the day among US adolescents. Future research should gather information about the barriers and facilitators of ST in adolescents by period of the day to help understand factors driving disparities. [ABSTRACT FROM AUTHOR]

In this work, a K-band traveling wave tube (TWT) based on carbon nanotube (CNT) cold-cathode is developed, which achieves a large output power as well as a high power gain. Compared to traditional thermionic cathode TWT, the CNT-based cold-cathode TWT shows significant advantages in fast response speed, miniaturization, integration, and high efficiency. The CNT-cathode of the TWT can emit a current of 9.26 mA, and a high current of 7.80 mA is delivered to the TWT's electron beam tunnel. The maximum current of the collector is 5.90 mA, indicating that the current density of the electron beam in the helix circuit tunnel reaches 750 mA/cm2 and higher, and the maximum transmittance rate in the experiment can reach 92%. The demonstrated CNT-based TWT can output a maximum power of 10.90 W with a power gain of 15.60 dB, and the maximum power gain achieved is 18.97 dB. The above experiment results imply that the CNT-cathode has great potential for application in TWT devices. • A K-band traveling wave tube based on carbon nanotube cold cathode is demonstrated. • Electron beam current density in TWT tunnel reaches 750 mA/cm2 and higher. • The maximum output power of the traveling wave tube reaches 10.9 W with a power gain of 15.6 dB. • A maximum power gain of 18.97 dB is achieved with the input power of 19.97 dBm. [ABSTRACT FROM AUTHOR]

By analysing the test data of 1029 British secondary school students’ performance on 20 Programme for International Student Assessment English reading items through the generalised deterministic input, noisy ‘and’ gate (G-DINA) model, the study conducted two investigations on exploring the relationships among the five reading comprehension skills defined by six English language experts. Skill groups, skill types and conflicting relationship were discovered in the investigation about the relationship among reading comprehension skills as part of the cognitive structure of the examinees, which provided insights into the sequence of reading skill training. The investigation about the relationship among reading comprehension skills in the problem-solving process, conducted at the item level, conceptualised skill relationship patterns as strategies for solving items. The study also demonstrated that saturated G-DINA model catered to the characteristics of reading comprehension skills and could be applied to tests involving highly interactive and hierarchical skills. [ABSTRACT FROM AUTHOR]

We propose a flexible model for correlated medical cost data with several appealing features. First, the mean function is partially linear. Second, the distributional form for the response is not specified. Third, the covariance structure of correlated medical costs has a semiparametric form. We use extended generalized estimating equations to simultaneously estimate all parameters of interest. B-splines are used to estimate unknown functions, and a modification to Akaike information criterion is proposed for selecting knots in spline bases. We apply the model to correlated medical costs in the Medical Expenditure Panel Survey dataset. Simulation studies are conducted to assess the performance of our method. [ABSTRACT FROM AUTHOR]

It is common to encounter latent variables with ordinal data in social or behavioral research. Although a mediated effect of latent variables (latent mediated effect, or LME) with ordinal data may appear to be a straightforward combination of LME with continuous data and latent variables with ordinal data, the methodological challenges to combine the two are not trivial. This research covers model structures as complex as LME and formulates both point and interval estimates of LME for ordinal data using the Bayesian full-information approach. We also combine weighted least squares (WLS) estimation with the bias-corrected bootstrapping (BCB; Efron Journal of the American Statistical Association, 82, 171-185, ) method or the traditional delta method as the limited-information approach. We evaluated the viability of these different approaches across various conditions through simulation studies, and provide an empirical example to illustrate the approaches. We found that the Bayesian approach with reasonably informative priors is preferred when both point and interval estimates are of interest and the sample size is 200 or above. [ABSTRACT FROM AUTHOR]

We have investigated the variation of mean wind almost continuously monitored by the Kunming (25.6°N, 103.8°E) MF radar over the period from August 2008 to August 2010. The mean circulation in zonal winds presents a obvious annual variation above 90 km and semiannual variation below 85 km, but has different direction up 90 km and down 85 km. An eastward flow is prevailing in spring and autumn below 85 km and in spring and summer up 90 km with amplitudes as large as 24 m/s and 21 m/s, respectively. But a westward flow dominates in summer and winter below 85 km and in autumn and winter up 90 km with amplitudes as large as −12 m/s and −10 m/s, respectively. Meanwhile the eastward wind dominates for all months at 85–90 km. The annual variation also appears in meridional wind below 90 km, which means a poleward flow occurs from September to April with amplitude maximum of 11 m/s, while the equatorward wind dominates almost for two years with maximum of −26 m/s above 90 km. Comparison of the wind vertical profile along with standard errors with the HWM07 model winds shows that the zonal wind agrees well with model in winter, autumn and summer, but the meridional wind in spring, winter and summer. [ABSTRACT FROM AUTHOR]

Vegetation is an important element and has such a complexity and uncertainty in remote sensing image that the extraction of vegetation by using remote sensing is a very difficult work. Vegetation is extracted using rich ETM+data in mineralized alteration zone of west Tianshan, Xinjiang to subsequently extract the minerals alteration. In order to ensure better minerals alteration, the feature-oriented principal component analysis + optimal density segmentation was proposed based on the analysis of spectral feature of vegetation and minerals alteration. The results showed that using ETM+ band 3 and band 4 combinations can better extract vegetation and this method is of great value in use. [ABSTRACT FROM AUTHOR]