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1,3‐Bis(boronic) esters can be readily synthesized from alkylBpin precursors. Selective transformations of these compounds hold the potential for late‐stage functionalization of the remaining C−B bond, leading to a diverse array of molecules. Currently, there are no strategies available to address the reactivity and, more importantly, the controllable regiodivergent functionalization of 1,3‐bis(boronic) esters. In this study, we have achieved controllable regiodivergent alkynylation of these molecules. The regioselectivity has been clarified based on the unique chelation patterns observed with different organometallic reagents. Remarkably, this methodology effectively addresses the low reactivity of 1,3‐bis(boronic) esters and bridges the gap in radical chemistry, which typically yields only the classical products formed via stable radical intermediates. Furthermore, the compounds synthesized through this approach serve as potent building blocks for creating molecular diversity. [ABSTRACT FROM AUTHOR]

1,3‐Bis(boronic) esters can be readily synthesized from alkylBpin precursors. Selective transformations of these compounds hold the potential for late‐stage functionalization of the remaining C−B bond, leading to a diverse array of molecules. Currently, there are no strategies available to address the reactivity and, more importantly, the controllable regiodivergent functionalization of 1,3‐bis(boronic) esters. In this study, we have achieved controllable regiodivergent alkynylation of these molecules. The regioselectivity has been clarified based on the unique chelation patterns observed with different organometallic reagents. Remarkably, this methodology effectively addresses the low reactivity of 1,3‐bis(boronic) esters and bridges the gap in radical chemistry, which typically yields only the classical products formed via stable radical intermediates. Furthermore, the compounds synthesized through this approach serve as potent building blocks for creating molecular diversity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fish sludge solubilization and phototrophic bioconversion is tested in aquaponics. • Anaerobic solubilization is superior to aerobic one in providing volatile fatty acids. • Phototrophic bioconversion is conducted using purple phototrophic bacteria. • Light-anaerobic condition achieves the desired biomass and mineral nutrients. • A novel multiloop aquaponics is proposed for the reuse of phototrophic nutrients. Nutrient recovery from fish sludge in aquaponics is crucial to improve the economic output of a system sustainably and hygienically. Currently, fish sludge is treated using conventional anaerobic and aerobic mineralization, which does not allow the recovery of valuable nutrients in fish wastes. In this study, a two-stage approach (named as solubilization process and phototrophic bioconversion) is proposed to convert fish sludge into mineral nutrients and biomass nutrients using purple phototrophic bacteria (PPB), thereby promoting the growth of plants and fish simultaneously in aquaponics. Anaerobic and aerobic solubilization methods are tested to pretreat the fish sludge, generating substrates for PPB. Anaerobic solubilization yields 2.1 times more soluble chemical oxygen demand (SCOD) and 3.7 times more total volatile fatty acid (t-VFA) from fish sludge compared with aerobic solubilization. The anaerobic solubilization effluent indicates a COD t-VFA /SCOD of 60% and a VFA comprising 13.3% acetate and 49.0% propionate for PPB. The phototrophic bioconversion using anaerobic solubilization effluent under the light-anaerobic condition results in the highest biomass yield (0.94 g COD biomass /g COD removed) and the highest PPB dominance (Ectothiorhodospira , 58.7%). The anaerobic solubilization and light-anaerobic phototrophic bioconversion achieves 54.1% of carbon recovery efficiency (CRE) (in terms of COD), as well as 44.8% and 91.3% of nutrient recovery efficiency (NRE) for N and P. A novel multiloop aquaponic system combined with PPB-based nutrient recovery is proposed for the reuse of mineral nutrients and PPB biomass generated from fish sludge. [ABSTRACT FROM AUTHOR]

Grassland aboveground biomass (AGB) is an important indicator for studying the change in grassland ecological quality and carbon cycle. The rapid development of high-resolution remote sensing and unmanned aerial vehicles (UAV) provides a new opportunity for accurate estimation of grassland AGB on the plot scale. In this study, the mountain grassland was taken as the research object. Using UAV Light Detection and Ranging (LiDAR) data and multispectral satellite images, the influence of topographic correction methods on AGB estimation was compared and a series of LiDAR metrics and vegetation indices were extracted. On this basis, a comprehensive indicator, the vegetation index-height-intensity model (VHI), was proposed to estimate AGB quickly. The results show that: (1) Among the four topographic correction methods, the Teillet regression has the best effect, and can effectively improve the accuracy of AGB estimation in mountain grassland. The correlation between corrected ratio vegetation index and AGB was the highest (correlation coefficient: 0.682). (2) Among the height and intensity metrics, median height and max intensity yielded the higher accuracy in estimating AGB, with Root Mean Square Error (RMSE) of 322 g/m2 and 333 g/m2, respectively. (3) The VHI integrated spectrum and LiDAR information, and its accuracy for AGB estimation for mountain grassland, was obviously better than other indicators, with an RMSE of 272 g/m2. We also found that the accuracy of VHI in univariate models was comparable to that of complex multivariate models such as stepwise regression, support vector machine, and random forest. This study provides a new approach for estimating grassland AGB with multi-source data. As a simple and effective indicator, VHI has shown strong application potential for grassland AGB estimating in mountainous areas, and can be further applied to grassland carbon cycle research and fine management. [ABSTRACT FROM AUTHOR]

This paper concerns the dynamic performance analysis of the vehicle ISD (inerter-spring-damper) suspension employing an eccentric inerter. Firstly, the quarter car model of the two basic vehicle suspension layouts involving an eccentric inerter, namely, the series-connected layout and the parallel-connected layout, is established. Then, by considering the overall performance such as the vehicle body acceleration, the suspension working space, and the dynamic tire load, the key parameters of the two suspensions are optimized by using the genetic algorithm. Simulation analysis results indicate that the series-connected vehicle ISD suspension is superior to the parallel-connected one, and all of the RMS values of the body acceleration, the suspension working space, and the dynamic tire load are decreased significantly by comparing to the conventional suspension, while the improvement of the parallel-connected vehicle ISD suspension is relatively poor. At last, the impact of the flywheel eccentricity and the screw pitch on the dynamic performance indices of the two suspensions is discussed, and the trade-offs among the three performances are analyzed, which will provide a guide method for the suspension design when considering the eccentric factor. [ABSTRACT FROM AUTHOR]

Accurate predictions from deep neural networks are crucial for distinguishing clean data and correcting noisy labels in current label noise learning methods. However, the conventional Softmax classifier used in most relevant works is highly sensitive to label noise due to its inherent competition-prompting mechanism, i.e., similar categories are encouraged to compete for limited confidence scores during class activation, especially between the noisy classes and the ground-truth, which can inevitably lead to suboptimal predictions and eventually hamper model performance. To address this inter-class competition problem, we propose a novel Sigmoid-based Sample Selection and Correction method named SigCo for learning with noisy labels. Different from previous works, we develop a Sigmoid-based network in which each Sigmoid classifier independently predicts its respective class, improving the reliability of the selection and correction process through more accurate predictions. Besides, in order to mitigate the negative impact of noisy labels, we design a noise-adaptive learning strategy by imposing stringent class masking constraints on clean samples to enhance the learning of discriminative features, while adopting a loose masking strategy for noisy data to improve the robustness to label noise. Additionally, we introduce a co-training strategy between our Sigmoid-based network and the conventional Softmax-based network to implicitly boost the generalization capability of the model. Extensive experiments on synthetic and real-world benchmarks show that SigCo consistently outperforms state-of-the-art methods. Especially on CIFAR-100N with 80% and 90% symmetric noise ratios, it improves test accuracy by 5.10% and 18.44%, respectively. [ABSTRACT FROM AUTHOR]

Shrub encroachment, characterized by the proliferation of shrubs into grasslands, is a challenge faced by grasslands worldwide that significantly impacts livestock production and ecosystem functions. Rapid and accurate estimation of shrub dominance is important for understanding changes in plant community structures and formulating grassland management policies. However, the limited spatial resolution of commonly used satellite imagery poses a challenge when estimating shrub dominance at the landscape scale. The rapid development of Unoccupied Aerial Vehicles (UAVs) has opened up new opportunities for cross-scale observations of shrub encroachment in grasslands by effectively bridging the scale gap between ground sampling and satellite image pixels while reducing the required groundwork. This study utilized ground reference data, UAV data (RGB, hyperspectral, and LiDAR), and satellite data (Sentinel-1 and Sentinel-2) to estimate shrub and total above-ground biomass (AGB) in temperate grasslands to map the shrub dominance. First, UAV data were applied at the plot scale for the classification of shrub and herbaceous vegetation using the maximum entropy model (MaxEnt), estimation of shrub AGB by employing the vegetation index weighted canopy volume model (CVM VI), and estimation of herbaceous AGB based on the partial least squares regression (PLSR). Second, UAV AGB mapping results were upscaled as samples at the landscape scale and integrated with satellite imagery to establish the shrub and total AGB models using the extreme gradient boosting (XGBoost). Finally, shrub dominance, represented as shrub AGB/total AGB, was mapped across the study area. We found that at the plot scale, the MaxEnt model achieved an overall accuracy of 0.990 for object-based classification. The CVM VI combined with canopy height model and narrow-band vegetation index achieved the highest accuracy for estimating shrub AGB (R2 = 0.821, RMSE = 30.1 g). The PLSR combined with features derived from all UAV data achieved the highest accuracy for estimating herbaceous AGB (R2 = 0.856, RMSE = 9.1 g/m2). At the landscape scale, the XGBoost achieved high accuracy for estimating both the shrub AGB (R2 = 0.719, RMSE = 4.2 g/m2) and total AGB (R2 = 0.961, RMSE = 5.0 g/m2). The high-precision mapping results further facilitate the generation of shrub dominance maps at a landscape scale. This study presents a more accurate and efficient framework for mapping shrub AGB, total AGB, and shrub dominance using multi-scale remote sensing data, which offers new approaches for large-scale grassland AGB mapping and monitoring of shrub encroachment in grasslands. • Multisensory UAV data were evaluated for shrub and herbaceous AGB estimation at the plot scale. • SAR and multispectral satellite data were used to map AGB and shrub dominance at the landscape scale. • Our multi-scale framework outperformed the traditional AGB estimation method. • Assessing shrub dominance is important for understanding shrub encroachment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tolfenpyrad and dinotefuran are two representative pesticides used for pest control in tea gardens. Their application may bring about a potential risk to the health of consumers. Therefore, it is essential to investigate the residue behavior, transfer and risk assessment of tolfenpyrad, dinotefuran and metabolites from tea garden to teacup. RESULTS: An effective analytical method was established and validated to simultaneously determine tolfenpyrad, dinotefuran and its metabolites (DN and UF) in tea. The average recoveries of tolfenpyrad, dinotefuran, DN and UF were in the range 72.1–106.3%, with relative standard deviations lower than 11.8%. On the basis of the proposed method, the dissipation of tolfenpyrad and dinotefuran in fresh tea leaves followed first‐order kinetics models with half‐lives of 4.30–7.33 days and 4.65–5.50 days, respectively. With application amounts of 112.5–168.75 g a.i. ha–1 once or twice, the terminal residues of tolfenpyrad and total dinotefuran in green tea were lower than 19.6 and 7.13 mg kg−1, respectively, and below their corresponding maximum residue limits. The leaching rates of tolfenpyrad and total dinotefuran during the tea brewing were in the ranges 1.4–2.3% and 93.7–98.1%, respectively. CONCLUSION: Tolfenpyrad and dinotefuran in tea were easily degraded. The RQc and RQa values for tolfenpyrad were 37.6% and 5.4%, which were much higher than for dinotefuran at 24.7% and 0.84%, respectively. The data indicated that there was no significant health risk in tea for consumers at the recommended dosages. The results provide scientific data regarding the reasonable use of tolfenpyrad and dinotefuran aiming to ensure safe tea consuption. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Propiconazole is widely used to control fungal diseases in field crops, including celery and onion. The potential risk to the environment and human health has aroused much public concern. Therefore, it is significant to investigate the degradation behaviour, residue distribution, and dietary risk assessment of propiconazole in celery and onion. RESULTS: A sensitive analytical method for determination of propiconazole residue in celery and onion was established and validated through high‐performance liquid chromatography tandem mass spectrometry. The average recovery rate of propiconazole ranged from 85.7% to 101.8%, with a relative standard deviation of 2.1–6.3%. For the dissipation kinetics, the data showed that propiconazole in celery and onion was degraded, with half‐lives of 6.1–6.2 days and 8.7–8.8 days respectively. In the terminal residue experiments, the residues of propiconazole were below 4.66 mg kg−1 in celery after application two or three times and were below 0.029 mg kg−1 in onion after application of three or four times with an interval of 14 days under the designed dosages. The chronic and acute dietary exposure assessments for propiconazole were valued by risk quotient, with all values being lower than 100%. CONCLUSION: Propiconazole in celery and onion was rapidly degraded following first‐order kinetics models. The dietary risk of propiconazole through celery or onion was negligible to consumers. The study not only offers a valuable reference for reasonable usage of propiconazole on celery and onion, but also facilitates the establishment of maximum residue limits in China. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

One water exopolysaccharide, designated G-EPS, was secreted by Rhodopseudomonas palustris GJ-22 culture media. The structure of G-EPS was characterized with HPGPC, GC–MS, methylation, 1D and 2D NMR, along with UV and FT-IR spectrum. The G-EPS molecular weight was 10.026 kilodalton, and is composed of D-mannose (92.8%) and d -glucose (7.2%). The purified G-EPS promoted plant growth and induced systemic resistance against TMV in Nicotiana benthamiana. These results suggested that G-EPS is an important active component of the bio-control capacity of GJ-22. • R. palustris GJ-22 secretes G-EPS, an exopolysaccharide, into culture media. • G-EPS is structurally composed of mannose and glucose. • G-EPS exhibits pro-growth and antiviral activities. • G-EPS induced systemic resistance that involved both the SA and JA/ET two signaling pathways. [ABSTRACT FROM AUTHOR]

One primary goal of physical education (PE) is to promote students' lifelong physical activity (PA). This goal implies that PE should not only improve students' PA in PE classes but also promote their PA outside of the school known as the "PE effect." Purpose: In this study, we proposed a two-pathway model of the "PE effect" and hypothesized that learning in PE and positive motivational experience in PE are two possible pathways through which the "PE effect" emerges. We tested the tenability of this two-pathway model from the perspective of knowledge learning and autonomous motivation in PE. Methods: A total of 394 eighth-grade students from five schools provided data on PA knowledge, out-of-school PA, and autonomous motivation toward PE and PA. Structural equation modeling was used to test the two-pathway model. Results: Results showed that the students' knowledge had a direct effect (β = .18, p < .05) on their autonomous motivation for PA and an indirect effect (β = .02, p < .05) on out-of-school PA through influencing autonomous motivation toward PA. Students' autonomous motivation for PE had a direct effect (β = .41, p < .05) on their autonomous motivation toward PA and an indirect effect (β = .04, p < .05) on out-of-school PA through autonomous motivation toward PA. Conclusion: These results indicate that the two-pathway model is tenable in terms of knowledge learning and autonomous motivation in PE and imply that teaching knowledge in an autonomy-supportive PE environment may be an effective way to promote students' out-of-school PA. [ABSTRACT FROM AUTHOR]

Acquiring scientific knowledge about physical activity is necessary for students to become physically literate for life, and cognitive engagement and cognitive levels of tasks are two components that often determine the effectiveness of knowledge acquisition. This study sought to determine the extent to which students' cognitive engagement in descriptive, relational and reasoning learning tasks contributed to their acquisition of knowledge and the extent to which cognitive engagement on lower-level tasks contributed to higher-level tasks (e.g. descriptive to relational to reasoning). The performance of students in descriptive, relational and reasoning tasks and knowledge acquisition was measured in 992 middle school students in active physical education lessons. The results revealed that students' performance in relational (regression coefficient = 0.09, p < 0.01) and reasoning (regression coefficient = 0.06, p < 0.01) tasks directly contributed to their acquisition of knowledge (R2 = 0.14). The performance of students in descriptive tasks indirectly contributed to knowledge acquisition through influencing their performance in relational and reasoning tasks (indirect effect = 0.09, p < 0.01). [ABSTRACT FROM AUTHOR]

There are substantial differences between the Chinese and US education systems. One difference is in the design and use of assessment due to differences in educational policies. This study described the differences in student learning outcomes, instructional approaches, and learner motivation in physical education as consequences of the policies in the two countries. Objectively measured data on skill and knowledge achievement and instructional procedures, and self-report data on student motivation were collected from a random sample of 870 students in 24 whole classes from eight Chinese middle schools and 1213 students in 39 classes from 15 US middle schools. Multivariate analyses of variance on class means revealed that Chinese students outperformed their US peers in skills, perhaps because skills were part of the high-stake tests for advancement in schooling. They were outperformed by the US students in a fitness knowledge test, perhaps because knowledge was not part of the high-stake tests. The differences in learning outcomes, instructional approaches, and motivation seem to suggest strong differentiated influences from the two countries' respective educational environments and assessment policies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore and reveal naïve conceptions and misconceptions about energy embedded in elementary school students’ prior knowledge. Students’ performance on standardized knowledge test was used to classify students into low, median and high levels of knowledge about the cardiovascular system. Semi-structured in-depth interviews were conducted with students in each group to extract their understanding of energy in relation to food choices, physical activities, and exercises. Analysis of the interview data generated six categories of naïve conceptions and two categories of misconceptions. Different conceptual change theories, including Chi’s ontological change theory, Ohlsson’s resubsumption theory, and enculturation theory were used to analyze and understand these naïve conceptions and misconceptions and why they could be robust to change. The analyses confirm the need to adopt a multi-theoretical approach to the understanding of students’ naïve conceptions and misconceptions (Chinn & Samarapungavan, 2009. Conceptual change-multiple routes, multiple mechanisms: A commentary on Ohlsson. Educational Psychologist, 44(1), 1-10). The findings encourage physical and health educators adopt different strategies to address the potential learning obstacles brought by students’ naïve conceptions and misconceptions. [ABSTRACT FROM AUTHOR]

Along with the prevalence of drug combination therapies, an increasing number of cases about drug-drug interactions (DDI) have been reported, which has drawn a lot of attention due to the potential toxicity and/or therapeutic failure. Pharmacokinetic interactions based on drug metabolic enzymes should be responsible for a great many of DDI. UDP-glucuronosyltransferases (UGT) as the main phase II metabolic enzymes are involved in the metabolism of many endogenous and exogenous substrates. Herein, we designed and optimized a validated cocktail method for the simultaneous evaluation of drug-mediated inhibition of the main five UGT isoforms using respective specific probe substrates (estradiol for UGT1A1, chenodeoxycholic acid for UGT1A3, serotonin for UGT1A6, propofol for UGT1A9/PROG and zidovudine for UGT2B7/AZTG) in human and rat liver microsomes by liquid chromatography–tandem mass spectrometry (LC MS/MS). Moreover, we investigated the risk of interactions among UGT probe substrates, and validated the cocktail method by known positive inhibitors of UGT isoforms. To minimize the substrates interaction, we developed two cocktail subgroups which were further optimized via exploring the experimental conditions. In particular, the cocktail inhibition assay for rapid assessment of in vitro rat UGTs was firstly reported and the values of K m in the liver microsomes from humans and rats were close to each other in the specific UGT subtype. In conclusion, this study has successfully established the cocktail approach to explore UGT activity, especially for UGT inhibition in a fast and efficient way. [ABSTRACT FROM AUTHOR]

This research investigates the effect of nanoparticle-diesel fuel blends on combustion characteristics, performances and exhaust emissions of a four-stroke single-cylinder diesel engine. Three types of nanoparticles employed in this experiment were aluminium oxide, carbon nanotubes and silicon oxide. The nanoparticles were dispersed in a dosage of 25 ppm, 50 ppm and 100 ppm with pure diesel and were labelled as DA25, DA50, DA100 (aluminium oxide blends), DC25, DC50, DC100 (carbon nanotubes blends) and DS25, DS50, DS100 (silicon oxide blends). The ultraviolet-visible spectrophotometer analysis was done for 200 h to quantify the stability of the nanoparticle-diesel fuel blends. The blended fuels were experimentally tested with YANMAR TF120M diesel engine at engine loads of 0%, 25%, 50%, 75% and 100% at a constant 1800 rpm engine speed. The results revealed that the brake specific fuel consumption reduced by up to 19.8% and brake thermal efficiency enhanced by 18.8%. Silicon oxide blends show better results than aluminium oxide blends in many aspects, such as higher combustion pressure, lower brake specific fuel consumption and lower carbon monoxide emissions. Aluminium oxide and silicon oxide show stable blend conditions with 28.1% and 22.0% absorption ratio at 200 h sedimentation time, while carbon nanotube blends were least stable with absorption ratio reducing to less than 30% after 10 h. Combustion analysis of carbon nanotube blends with diesel show that carbon nanotubes have the potential to be further researched as an additive for diesel fuel due to significant combustion improvement in NO x emissions. However, the issue on the stability of carbon nanotube blends must be resolved before its potential can be fully utilized. [ABSTRACT FROM AUTHOR]

Presents information on a study that measured the dielectric properties and positron annihilation lifetime spectra of the ceramics with the nominal composition Sr[sub1-x]La[subx]TiO[sub3]. Methodology of the study; Results and discussion on the study.

Presents a study on the defect structure of the dielectric ceramics using the positron annihilation technique. Experimental details; Results and discussion; Conclusion.

In 1971, scientists from Mahidol University in Thailand and the Smithsonian Institution in the USA formed a research team to study a new species of Schistosoma in the Mekong River in Thailand and Laos. The studies, completed during 1971–1973, prior to the construction of any dams or restrictions to the natural flow regime of the Mekong River, provide a unique description of the natural ecological state of the river that can serve as a baseline for current research. The natural transmission of Schistosoma japonicum, Mekong Strain, was first reported on Khong Island, Laos in 1973 using sentinel mice. The first detailed description of the habitat ecology of the snail vector Neotricula aperta was done on-site in 1971 simultaneously with that research and is unique in providing the only description of the river shoreline habitat before any dams were built and any alteration of the natural flow regime was in place. Aggregating current information in a Place-Based Conceptual Model (PBCM) as an organizing template, along with current habitat models that combine ecological data with e-flows, can be developed and used as a tool to predict suitable habitats for snails. The natural flow regime of the Mekong River prior to any impoundments is described with current updates on the potential impacts of climate change and dams with flow-related snail habitat characteristics, including sediment drift and water quality. The application of the PBCM to describe and compare descriptive information on current and potential future N. aperta/S. mekongi habitat is discussed. Author summary: We provide a unique profile of Neotricula aperta habitat in the Mekong River in Laos and Thailand during the transmission of Schistosoma mekongi prior to the construction of any dams on the river. A Place-Based Conceptual Model (PBCM) is described to help identify potential new areas, with suitable habitats for snails and disease transmission. The natural flow regime of the Mekong River prior to any impoundments is described with current updates on the potential impacts of climate change and flow-related snail habitat characteristics, including sediment drift and water quality. Environmental management strategies are outlined, emphasizing environmental flow (e-flow) and habitat models, with the potential to mitigate N. aperta distribution and S. mekongi disease transmission. The PBCM can serve as a template to aggregate and compare historical baseline information (Before dams) with current data (After dams) to create predictive models describing suitable habitats for N. aperta and other snail intermediate hosts and vectors along shoreline areas of the Mekong River continuum. The PBCM model could be a powerful management tool when combined with habitat suitability and e-flow models. Adding schistosome biomarkers currently under development in a One Health context to select possible areas of a river likely to support disease transmission could extend the value of the model. [ABSTRACT FROM AUTHOR]

Shikonin is a naphthoquinone pigment extracted from roots of Lithospermum erythrorhizon Sieb. et Zucc. (Boraginaceae), and possesses various pharmaceutical activities, such as anti-inflammation and anti-cancer effects. In addition, shikonin as a natural red colorant for food garnishment and cosmetics ingredient is widely used in the world. However, the inhibition risk of shikonin on cytochrome P450 (CYP) remains unclear. The aim of this study was to investigate the potential inhibition of shikonin against CYP1A2, CYP2B1/6, CYP2C9/11, CYP2D1/6, CYP2E1 and CYP3A2/4 activities in human and rat liver microsomes through cocktail approach in vitro. The results demonstrated that shikonin exhibited no time-dependent inhibition of CYP activities. In human liver microsomes, shikonin was not only a mixed inhibitor of CYP1A2, CYP2B6, CYP2C9, CYP2D6 and CYP3A4, but also a competitive inhibitor of CYP2E1, with K i values no more than 7.72 μM. In rat liver microsomes, shikonin also exhibited the mixed inhibition on CYP1A2, CYP2B1, CYP2C11, CYP2D1, and the competitive inhibition on CYP2E1. Interestingly, shikonin presented an atypical kinetic inhibition of CYP3A2-mediated midazolam 1-hydroxylation in rats. In conclusion, the relatively low K i values of shikonin would have a high risk potential to cause the possible toxicity, especially drug-drug or food-drug interactions based on the potent inhibition of CYP enzymes. [ABSTRACT FROM AUTHOR]

Based on the job demands--resources model, the study developed and validated an instrument that measures physical education teachers' job demands--resources perception. Expert review established content validity with the average item rating of 3.6/5.0. Construct validity and reliability were determined with a teacher sample (n = 397). Exploratory factor analysis established a five-dimension construct structure matching the theoretical construct deliberated in the literature. The composite reliability scores for the five dimensions range from .68 to .83. Validity coefficients (intraclass correlational coefficients) are .69 for job resources items and .82 for job demands items. Inter-scale correlational coefficients range from -.32 to .47. Confirmatory factor analysis confirmed the construct validity with high dimensional factor loadings (ranging from .47 to .84 for job resources scale and from .50 to .85 for job demands scale) and adequate model fit indexes (root mean square error of approximation = .06). The instrument provides a tool to measure physical education teachers' perception of their working environment. [ABSTRACT FROM AUTHOR]

Research has shown that interest in knowledge facilitates students' academic achievement in learning. Because individual interest is often based on how much one knows, in other words existing or prior knowledge, studying adolescents' interest in health-enhancing physical activity and its benefits should address the relation between the interest and their existing or prior physical activity knowledge. Understanding this relationship may help us facilitate students to not only develop interest in knowing more about but also actual adopt a healthy, active lifestyle. This study used a large-sample structural equation design to identify the relationship between middle school students' interest in physical activity knowledge and their prior physical activity knowledge, and to assess the change of this relationship over time. Guided by the declarative-procedural knowledge framework, latent growth models were developed and tested on data collected from a random sample of 3882 students from ten middle schools. The latent growth curve model indicated that, 1) on average, students experienced a significant interest decline in both procedural and declarative knowledge; 2) prior knowledge helped slow the decline and facilitated interest growth in knowledgeable students. The results suggest that existing knowledge determined the interest change. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new method is proposed for sizing aerosols without refractive index. • The LSIF is used to characterize unconstrained PSD and refractive index. • Deep learning is adopted to retrieve unconstrained PSD efficiently (about 100 ms). • An integrated and cost-effective prototype is designed and verified. Existing light-based aerosol size analyzers suffer from measurement errors or even fail to measure particle size distribution (PSD) when the refractive index is unknown. To overcome this limitation, we introduced a new aerosol sizing method without the prior refractive index using the light scattering intensity field (LSIF) and deep learning. The LSIF is the intensity distribution of the light scattered in all directions around aerosol particles, which can be used to simultaneously characterize the PSD and the refractive index. A PSD retrieval approach based on deep learning was developed to efficiently retrieve (about 100 ms) the unconstrained PSD (141 independent channels). Our proof-of-concept prototype was tested on various aerosol samples with different particle sizes and refractive indices, where the relative standard deviation (RSD) of the particle size was 1.94% in the test of monodisperse aerosols and the Kullback-Leibler divergence of PSD was 0.13 in the test of polydisperse aerosols. [ABSTRACT FROM AUTHOR]

Changes in land use and landscapes have a direct impact on the regional eco-environment. It is of great importance to understand the change pattern of land use, landscapes, and their mechanism on the ecological quality, especially ecologically fragile areas. The northern sand-prevention belt (NSPB) is an important ecologically fragile area in China, which has a large influence on the ecological security of the entire country. Based on the land use data of the NSPB in 2000, 2010, and 2018, we studied the spatio-temporal characteristics of land-use change and change in landscape patterns. The ecological quality represented by the remote sensing-based desertification index (RSDI) was calculated using satellite images. The effects of land use and landscape patterns on RSDI were analyzed by geographic detector and geographically weighted regression. Important results include the following: (1) Land-use change in the study area was high during 2000–2010 but slower in 2010–2018. Grassland was the largest land-use type in the NSPB, and varied greatly in terms of total change and spatial location. The major change was the conversion between dense and moderate grass, with 64,860 km2 of dense grass turning into moderate grass, and 48,505 km2 changing the other way. (2) Among the four landscape metrics, patch density, area-weighted mean fractal dimension, and edge density increased, whereas the aggregation index decreased, which indicated that the landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. Spatially, the landscape metrics presented a strip distribution in the east of the NSPB. (3) The effects of various land-use types on ecological quality, from high to low, were unused land, woodland, dense grass, cropland, moderate grass, built-up land, sparse grass, and waterbody. The areas where the ecological quality was greatly affected by the landscape patterns were concentrated in the agro-pastoral ecotone and the forest-steppe ecotone. The results of this study reveal the trends of land use and landscape patterns in the NSPB over 18 years and can help to understand their mechanism on ecological quality, which is of significance for the management of this area. • LUC in the NSPB was active from 2000 to 2010 and weakened from 2010 to 2018. • The landscape was developing towards heterogeneity, fragmentation, complexity, and aggregation. • The effects of land use and landscape on ecological quality were studied by GD and GWR. [ABSTRACT FROM AUTHOR]

Wetlands are important habitats on biodiversity protection. In this study, the relationship between wetland and avifauna changes in the Yellow River Delta Wetland was studied. Remote sensing and geographic information system provided an advanced platform for the research. After the avifauna survey was performed from 2012 to 2013, the birds’ variation and driving factors were analyzed. The results showed that the flow into the wetland increased continuously from 2000, and the increased of artificial wetland prevented the wetland degradation, although at the same time the total wetland area decreased. Medium grassland, tidal flat and pond are the three main landscapes which are beneficial for the habitation of birds. The migrating numbers of red-crowned crane increased significantly from 2005, and the overwintering numbers increased from 2009. The study results show that the key land use types for protecting endangered species of birds are medium grassland, tidal flat and pond landscapes. Wetland changes are sensitive to the birds and significantly affected by the flow. We suggest that the artificial wetland project should enhance the three land use type area to ensure the wetland restoration. [ABSTRACT FROM AUTHOR]

This work reported a high quality photonic crystal film with an ultra-narrow photonic bandgap obtained via a chemical synthetic route. The bandgap is much narrower than that of traditional colloidal crystals, which makes the film qualified for use in optical devices. The narrow PBG originates from not only the high crystallinity and uniform orientations of microcrystals within the film but also the very close refractive indices between the silica and the polymer matrix. Due to the matching of the refractive index, the amorphous contents of the film are optically transparent and do not interfere with the reflection, so that the photonic crystal film is tolerant of the existence of disordered contents. [ABSTRACT FROM AUTHOR]

Lubricating oil improves the reliability of compressors and systems, whereas increases the system complexity. Compared with other types of compressors that have oil-free models, a rolling piston compressor has more leakage paths and bigger leakage loss. Therefore, the leakage is an important problem to be solved in order to develop an oil-free rolling piston compressor. The paper put forward a new structure of rotary compressor adopting a low pressure shell, connecting the cavities within piston and behind vane to the cavity at suction pressure and using radial compliance mechanisms. Then the leakage models were developed to calculate the mass flow rates within both the present rolling piston compressor without any oil as sealant and the new structure of oil free compressor. Results showed that by the new structure, the influences of leakage on the performance of a R290 oil free rolling piston compressor can be largely decreased. [ABSTRACT FROM AUTHOR]

In physical education, it has become necessary for children to learn kinesiological knowledge for understanding the benefits of physical activity and developing a physically active lifestyle. This study was conducted to determine the extent to which cognitive assignments about healthful living and fitness contributed to knowledge growth on cardiorespiratory fitness and health. Fourth grade students (N = 616) from 15 randomly sampled urban elementary schools completed 34 cognitive assignments related to the cardiorespiratory physical activities they were engaged in across 10 lessons. Performance on the assignments were analyzed in relation to their knowledge gain measured using a standardized knowledge test. A multivariate discriminant analysis revealed that the cognitive assignments contributed to knowledge gain but the contribution varied assignment by assignment. A multiple regression analysis indicated that students’ assignment performance by lesson contributed positively to their knowledge growth scores. A content analysis based on the constructivist learning framework showed that observing–reasoning assignments contributed the most to knowledge growth. Analytical and analytical–application assignments contributed less than the constructivist theories would predict. [ABSTRACT FROM PUBLISHER]

Abstract: Physical education and health education are relevant avenues for adolescents to learn knowledge and behavior related to energy-balanced living. Grounded in the framework theory of conceptual change, this study examined ninth graders' energy balance knowledge (i.e., concepts, principles, and strategies underlying the scientific mechanism and the outcome of energy balanced/imbalanced living) and physical activity in a healthful-living curriculum (i.e. combination of physical education and health). The students (N =195) were measured using concept mapping, accelerometers, and three-day physical activity recall. It was found that the students differed in energy balance knowledge where most (83%) lacked a higher-order relational understanding. Physical activity in physical education class or after school did not significantly differ by students' mental model levels concerning energy balance knowledge. The findings suggest that an ecological learning context with moderate physical activity should be provided to help students make sense of energy balance knowledge through lived experiences. [Copyright &y& Elsevier]

Physical activity is critical to healthy development of children. It is well documented that helping children develop and sustain a physically active lifestyle requires children to become motivated. Many studies have been conducted in the past 2.5 decades on determinants and correlates for children and adolescents' physical activity motivation. The findings have informed researchers and practitioners about motivation sources for children and effective strategies to motivate children in given physical activity settings. Built on the extensive knowledge base and theoretical platforms formed by these research studies, the purpose of this article is to take a look at the current research landscape and provide subjective thoughts about what we still need to know about children's physical activity motivation. The product of this subjective thinking process rendered 10 potential questions for future research on children's physical activity motivation in both in-school and out-of-school settings. These topics encompass those focusing on children's physical activity motivation as a mental dispositional process, those conceptualizing the motivation as an outcome of person–environment interactions, and those attempting to dissect the motivation as an outcome of social–cultural influences and educational policies. It is hoped that the topics can serve researchers interested in children's physical activity motivation as starting blocks from which they can extend their conceptual thinking and identify research questions that are personally meaningful. It is also hoped that the list of potential questions can be helpful to researchers in accomplishing the imperative and significant mission to motivate children to be physically active in the 21st century and beyond. [ABSTRACT FROM PUBLISHER]

Expectancy value theory presumes that learners’ motivation is determined by their expectancy beliefs and task values associated with learning tasks. This study examined students’ cost and its relation to expectancy beliefs, other task value components in physical education. Middle school students (N = 593) from 11 schools completed the expectancy-value questionnaire. Qualitative analysis of students’ responses to open-ended questions showed motivational cost originated from curriculum content, instructional conditions/elements, physical discomfort, lack of social support and competence and teacher factors. Chi-square analysis suggests that students’ motivational cost is associated with their hypothetical choices of attending physical education. Motivational cost was found to be negatively associated with other task value components, but not with expectancy beliefs. [ABSTRACT FROM AUTHOR]

• The RSDI is suitable for monitoring aeolian desertification. • The areas with significant restoration (34.1%) exceeded those with significant deterioration (6%) in the NSPB. • In the areas with significant restoration, 57.4% of the land was mainly affected by human activities. The northern sand-prevention belt (NSPB) is the key area for sand control in China, and the various ecological projects conducted there are important to the Chinese strategy for ecological security. In this paper, a new remote sensing-based desertification index (RSDI) based on principal component analysis was constructed from four aspects of vegetation greenness, surface moisture, soil grain size, and surface radiation. The overall evaluation accuracy of the index was 89.2%, and the kappa coefficient was 0.80, indicating high sensitivity to different degrees of aeolian desertification and suitability for multiscale research. The coefficient of variation, Mann–Kendall test, Theil–Sen median trend analysis, and residual analysis were used to analyze the spatiotemporal changes and driving forces of the RSDI in the NSPB from 2000 to 2020. The RSDI was used to compare aeolian desertification in different subregions, land use types, and ecological project areas. The important results are as follows: (1) the trend of the average RSDI was downward, but it increased significantly in 2008–2009 and 2013–2014; (2) the RSDI was characterized by relatively high volatility in 28.9% and moderate volatility in 27.1% of the area; (3) the areas with significant restoration (34.1%) greatly exceeded those with significant deterioration (6%), whereas 59.9% of the total area was stable; and (4) within the area with significant restoration, 57.4% was primarily affected by human activities, and 42.4% was primarily affected by climate change; however, most of the area with significant deterioration (71.1%) was affected by human activities. In general, the degree of aeolian desertification in the NSPB has decreased in the past 20 years and its ecological quality has continued to recover. However, unreasonable human activities still need to be reduced, and the ecological management of areas under serious threat of desertification needs to be strengthened. [ABSTRACT FROM AUTHOR]

Motivation to learn is a disposition developed through exposure to learning opportunities. Guided by the expectancy-value theory of Eccles and Wigfield (1995), this study examined the extent to which expectancy belief and task value influenced elementary school students’ physical activity and knowledge learning in physical education (PE). Students (N = 753) from 15 US public schools contributed student-level and class-level data. With a 2-level design, the data were analyzed using hierarchical linear modeling. Physical activity (t = 3.18; p < .01) positively predicted fitness knowledge. Attainment value (i.e. perception of importance) as the only expectancy-value construct, significantly predicted fitness knowledge (t = 3.07; p < .01), when physical activity was held constant. As the physical activity intensity increased, the positive prediction of attainment value to knowledge attenuated and then turned negative (t = –3.10; p < .01). The study indicated that although a physically-active context helps students to make sense of fitness knowledge, a vigorous context shifts their motivation away from cognitive learning, toward physical participation. To resolve the difficulty of attaining learning objectives both physically and cognitively, PE teachers may want to maintain an active learning context with moderate physical intensity. Future research should address the effect of learner motivation on dual or multiple learning outcomes in PE. [ABSTRACT FROM AUTHOR]

Abstract: This study reports adolescent expectancy-value motivation, and its relation to fitness knowledge and psychomotor skill learning in physical education. Students (N =854) from 12 middle schools provided data on expectancy-value motivation, fitness knowledge and psychomotor skill learning. Results from dependent t-test and MANOVA indicated that 8th grade students rated task values significantly lower than 6th grade while their expectancy beliefs did not significantly differ. Students gained sizable fitness knowledge (d =0.58, p <0.05) and badminton skill (d =1.40, p <0.05). Multiple regression analyses revealed that expectancy-value motivation did not significantly predict learning in fitness knowledge or psychomotor skills. These findings suggest that expectancy-value motivation might predict engagement and performance, but not necessarily learning achievement in physical education. [Copyright &y& Elsevier]

Abstract: In this paper, we estimate the size of ''s in the famous L. Zalcman''s lemma. With it, we obtain some uniqueness theorems for meromorphic functions f and when they share two transcendental meromorphic functions. [Copyright &y& Elsevier]

Abstract: Ceramic samples with nominal compositions of (Ca1− x Sr x )0.9Pr0.001Zn0.099TiO3 (x =0, 0.05, 0.10, 0.15, 0.20) were prepared by a mixed oxide method. When examined by the X-ray diffraction (XRD) analysis, the samples revealed a main CaTiO3 phase with small amounts of a second Zn2TiO4 phase. All of the ceramic samples emitted red phosphorescent light at about 613nm when excited by light of a wide wavelength range (200nm to about 500nm). The partial substitution of Sr for Ca, up to approximately 10at%, significantly enhanced the phosphorescence intensity and lifetime. The long lasting phosphorescence could be observed with naked eyes in dark room for more than 10min in both air and water at room temperature. [Copyright &y& Elsevier]

Abstract: Students’ learning has been the center of schooling. This study examined the contribution of situational interest motivation and cognitive engagement in workbooks to student achievement in learning health-related fitness knowledge. Situational interest, performance on solving workbook problems, and knowledge gain in cardio-respiratory fitness and benefits were measured in 670 third-grade students from 13 randomly selected urban elementary schools. Structural equation modeling and regression curve estimation analyses revealed that situational interest contributed little to workbook performance and knowledge gain. Performance on solving workbook problems contributed significantly to knowledge gain. The results also show that skipping workbook tasks had stronger negative impact on knowledge gain than performing the tasks incorrectly, suggesting the importance of engaging students in the learning process by attempting the workbook tasks. The findings reinforced the value of using workbooks to facilitate cognitive knowledge learning in physical education, but raised questions about the direct function of situational interest on engaging students in cognitive learning. [Copyright &y& Elsevier]

Constructivist physical education emphasizes cognitive engagement. This study examined the impact of a constructivist curriculum on in-class physical activity. Caloric expenditure in metabolic equivalents (MET) and vector magnitude count (VM) data from a random sample of 41 constructivist lessons were compared with those from a random sample of 35 nonconstructivist lessons. Statistical analyses revealed that students in both curriculum conditions were active at a similarly low-moderate level (MET = 2.6 for experimental, 2.5 for comparison, p = .30). Differences (p < .05) were found between the three units within the constructivist curriculum. The findings suggest that the constructivist approach may facilitate knowledge learning with little risk of reducing in-class physical activity. [ABSTRACT FROM AUTHOR]

Achievement goals and interests are recognized as primary motivators for learning in physical education. The study examined the dynamics of the motivators as associated with organized outside-school physical activity experiences and learning outcomes. Data of achievement goals, personal interest, learning outcomes, and outside-school experiences were gathered from students (N=104) randomly selected from two middle schools. The correlation analysis revealed a complex relationship among the motivators and learning outcomes. The MANOVA showed that the students participating in organized outside-school physical activities had a stronger ego-goal orientation and were more physically active in learning. Their knowledge and skill assessment outcomes did not differ from other students. The findings suggest that participation in outside-school programs may result in an active engagement, but may not lead to a paralleled learning achievement. These findings depicted a complex and dynamic web of relationships between the motivators and learning outcomes that needs to be addressed in future research. [Copyright &y& Elsevier]

The purpose of this study was to examine individual and situational interests in learning motor skills as associated with gender and skill. Individual and situational interests and motor skill were measured in middle school girls (n = 109) and boys (n = 82). A correlation analysis for the entire sample showed a moderate correlation between skill and individual interest (r = .63) and weak relationships between individual and situational interest (r < .10) and between situational interest and skill (r < .18). A MANOVA analysis revealed a difference between the boys and girls in situational interest at a borderline significance level (p = .05). However, when individual interest, skill, and gender were compared between students with high or low situational interest in a hierarchical log linear model, it was found that both groups did not differ in number of boys and girls (p = .98). But the high situational interest group had more students with high skill (p = .001) and high individual interest (p = .02). The results suggest that discrepancies in acquired skill accounted for the gender difference and that acquired skill is associated with individual interest and high situational interest in learning motor skills. [Copyright &y& Elsevier]

Background. Situational interest is articulated theoretically as a construct associated with five dimensional sources: novelty, challenge, attention demand, exploration intention, and instant enjoyment. Aims. This study aimed to examine the influence of the dimensional sources on situational interest. It was hypothesised that the dimensional sources function differently to contribute to situational interest and that the influence of a source might be mediated by others. Sample. Two samples of 7th, 8th, and 9th grade students were used in the study. There were 281 students (57% male, 43% female) in the first sample and 191 (47% male, 53% female) in the second. Method. Students in Sample A evaluated situational interest and the dimensional sources in tasks of analysing jogging and gymnastic stunts on video. Those in Sample B evaluated them in tasks of learning basketball. Correlation and regression analyses and path analyses were used to test the theoretical model. Results. Instant Enjoyment determined situational interest. Exploration and Novelty had positive influences on situational interest via enhancing Instant Enjoyment. Challenge showed little influence. The path analyses for both samples confirmed the inter-dimensional mediation effects of the sources. Conclusion. The analysed data support the hypotheses. The dimensional sources had unequal influences on situational interest and the mediation effects among themselves at times strengthened or weakened each other's influences. The findings suggest that to increase situational interest, educators should offer students ample exploratory opportunities during student-task interaction that can lead to instant enjoyment for learning. [ABSTRACT FROM AUTHOR]

Northern China has been long threatened by aeolian desertification. In recent years, all levels of the Chinese government have performed a series of ecological protection and sand control projects. To grasp the implementation effects of these projects and adjust policies in time, it is necessary to understand the process of aeolian desertification quickly and accurately. Remote sensing technologies play an irreplaceable role in aeolian desertification monitoring. In this study, the Zhenglan Banner, which is in the hinterland of the Hunshandake Sandy Land, was considered as the research area. Based on unmanned aerial vehicle (UAV) images, ground survey data, and Landsat images called in Google Earth Engine (GEE), the aeolian desertified land (ADL) in 2000, 2004, 2010, 2015, and 2019 was extracted using spectral mixture analysis. A desertification index (DI) was constructed to evaluate the spatial and temporal dynamics of the ADL in the Zhenglan Banner. Finally, a residual analysis explored the driving forces of aeolian desertification. The results showed that (1) the ADL area in the Zhenglan Banner has been trending downwards over the past 20 years but rebounded from 2004 to 2010; (2) over the past 20 years, the area of slightly, moderately, and severely desertified land has decreased at annual rates of 0.4%, 2.7%, and 3.4%, respectively; (3) human activities had significantly positive and negative impacts on the aeolian desertification trend for 20.0% and 21.0% of the study area, respectively, but not for the rest. This paper explored new techniques for rapid aeolian desertification monitoring and is of great significance for controlling and managing aeolian desertification in this region. [ABSTRACT FROM AUTHOR]

• LC–MS/MS analysis method was developed for arachidonic acid metabolome. • The method was firstly applied for eicosanoids determination in a mouse model of breast cancer. • Significant content differences of arachidonic acid and its metabolites were found. • Eicosanoids may be used as new biomarkers to assist for breast cancer diagnosis. Arachidonic acid (AA) is closely associated with breast cancer. In addition to the two metabolic pathways regulated by cyclooxygenase and lipoxygenase, AA has a third metabolic pathway through which cytochrome P450 (CYP) enzymes produce hydroxyeicosatetraenoic acids (HETEs) and epoxyeicosatrienoic acids (EETs). The targeted CYP-mediated pathway of AA can not only kill cancer cells but also inhibit the interstitial microenvironment around a tumor. Therefore, it makes sense to identify potential biomarkers from the AA metabolome for the diagnosis and treatment of breast cancer. This study established a liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for the analysis of AA and its main metabolites, EETs and HETEs, in MMTV-PyMT mice, a spontaneous breast cancer mouse model. The results showed that there were significant differences in the concentrations of AA, 12-HETE, 19-HETE and 8,9-EET in plasma and tumor tissues between normal and MMTV-PyMT mice. Therefore, the eicosanoids mentioned above may be used as new biomarkers for breast cancer diagnosis. This study provides a new perspective for the recognition and diagnosis of breast cancer. [ABSTRACT FROM AUTHOR]

Respiratory behaviors provide useful measures of lung health. The current methods have limited capabilities of continuous characterization of respiratory behaviors, often required to assess respiratory disorders and diseases. This work presents a system equipped with a machine learning algorithm, capable of continuously monitoring respiratory behaviors. The system, consisting of two wireless wearable sensors, accurately extracts and classifies the features of respiratory behaviors of subjects within various postures, wirelessly transmitting the temporal respiratory behaviors to a laptop. The sensors were attached on the midway of the xiphoid process and the costal margin, and 1 cm above the umbilicus, respectively. The wireless wearable sensor, consisting of ultrasound emitter, ultrasound receiver, data acquisition and wireless transmitter, has a small footprint and light weight. The sensors correlate the mechanical strain at wearing sites to lung volume by measuring the local circumference changes of the chest and abdominal walls simultaneously. Eleven subjects were recruited to evaluate the wireless wearable sensors. Three different random forest classifiers, including generic, individual, and weighted-adaptive classifiers, were used to process the wireless data of the subjects at four different postures. The results demonstrate the respiratory behaviors are individual- and posture-dependent. The generic classifier merely reaches the accuracy of classifying postures of 21.9 ± 1.7% while individual and weighted-adaptive classifiers mark substantially high, up to 98.9 ± 0.6% and 98.8 ± 0.6%, respectively. The accurate monitoring of respiratory behaviors can track the progression of respiratory disorders and diseases, including chronic respiratory obstructive disease (COPD), asthma, apnea, and others for timely and objective approaches for control. • Continuously monitor and extract features of respiratory behaviors completely and accurately. • Machine-learning enabled study of individuality of respiratory behaviors. • Postures recognition based on general respiration contributing to monitor posture-related respiratory diseases, like apnea. [ABSTRACT FROM AUTHOR]

Rheumatic heart disease (RHD) is an autoimmune disease caused by rheumatic fever following group A hemolytic streptococcal infection and primarily affects the mitral valve. RHD is currently a major global health problem. However, the exact pathological mechanisms associated with RHD-induced cardiac valve damage remain to be elucidated. The endothelial-mesenchymal transition (EndMT) serves a key role in a number of diseases with an important role in cardiac fibrosis and the activin/Smad2 and 3 signaling pathway is involved in regulating the EndMT. Nevertheless, there are no studies to date, to the best of the authors' knowledge, investigating the association between RHD and EndMT. Thus, the aim of the current study was to investigate the potential role of EndMT in cardiac valve damage and assess whether activin/Smad2 and 3 signaling was activated during RHD-induced valvular injury in a rat model of RHD induced by inactivated Group A streptococci and complete Freund's adjuvant. Inflammation and fibrosis were assessed by hematoxylin and eosin and Sirius red staining. Serum cytokine and rheumatoid factor levels were measured using ELISA kits. Expression levels of activin/Smad2 and 3 signaling pathway-related factors [activin A, Smad2, Smad3, phosphorylated (p-)Smad2 and p-Smad3], EndMT-related factors [lymphoid enhancer factor-1 (LEF-1), Snail1, TWIST, zinc finger E-box-binding homeobox (ZEB)1, ZEB2, α smooth muscle actin (α-SMA) and type I collagen α 1 (COL1A1)], apoptosis-related markers (BAX and cleaved caspase-3) and valvular inflammation markers (NF-κB and p-NF-κB) were detected using reverse transcription-quantitative PCR and western blot analyses. Compared with the control group, the degree of valvular inflammation and fibrosis, serum levels of IL-6, IL-17, TNF-α and expression of apoptosis-related markers (BAX and cleaved caspase-3) and valvular inflammation marker (p-NF-κB), activin/Smad2 and 3 signaling pathway-related factors (activin A, p-Smad2 and p-Smad3), EndMT-related factors (LEF-1, Snail1, TWIST, ZEB 1, ZEB2, α-SMA and COL1A1) were significantly increased in the RHD group. These results suggested that the activin/Smad2 and 3 signaling pathway was activated during the development of valvular damage caused by RHD and that the EndMT is involved in RHD-induced cardiac valve damage. [ABSTRACT FROM AUTHOR]

Examines the multidimensionality of situational interest in physical education among middle school students in the United States. Use of Development and revision of the Situational Interest Scale; Dimensions of situational interest; Employment of exploratory and confirmatory factor analysis; Definition of situational interest.

Focuses on educational value orientations which reflect teachers' philosophical beliefs about schooling which serve as the basis on which teachers make their decisions. What the subsequent examination of the representativeness of the statment led to; Purpose of the investigation.

Examines the patterns of holding interest for physical activities in a state physical education curriculum for secondary schools. Determination and analysis of patterns; Types of interest; Activities associated with patterns; Basis of holding interest; Focus for curricular decisions.