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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]

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]

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]

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]

• 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]

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]

Tebuconazole is an effective but potentially carcinogenic fungicide. Tebuconazole residues in loquat and sugarcane were investigated, together with an analysis of their dietary risk. Solid-phase extraction and high-performance liquid chromatography-tandem mass spectrometry showed fortified recoveries of 87% to 98%, with standard deviations ≤ 6.4%. The tebuconazole residues were below 6.34 mg kg−1 for whole loquat and 0.80 mg kg−1 for sugarcane. Based on the final residue test, the chronic hazard index was 90.74% in whole loquat and sugarcane, while the acute hazard index ranged from 66.32% to 109.49% for loquat and 33.37% to 76.93% for sugarcane. The assessment of potential dietary risk showed that while loquats may represent an acute risk to human health, whereas sugarcane consumption was safe. A 21-day pre-harvest interval is proposed to comply with maximum residue limit regulations and the observed risks when using 430 g/L tebuconazole for treating sugarcane. These findings offer guidance for tebuconazole formulation and use. [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]

Organoboronates are synthetically useful and highly valuable building blocks in synthetic and medicinal chemistry. Two‐electron reactions allow for the rapid construction of organoboronates via nucleophilic 1,2‐boron shift of boron ate complexes or MIDA‐mediated 1,2‐boryl migration. Radical approaches through 1,2‐boron shift of neutral boronic esters or boron ate complexes have been demonstrated to be feasible, providing complementary methods to access these privileged scaffolds. In this Review, recent achievements are highlighted and future opportunities are discussed, with an emphasis on different operative modes of catalysis and reaction pathways. [ABSTRACT FROM AUTHOR]

Purpose: Based on the theorized concept "Curriculum Safety Zone (CSZ)," this study was conducted to identify the factors for breaking CSZ by contrasting the experiential accounts of two pre-service teacher groups who taught within or outside of their CSZ. Method: Pre-service teachers (n = 14) from a sport-centered PETE program were trained to teach a Health-First curriculum module and their peers (n = 14) a traditional sport module. Each group taught their respective module to 14 intact 7th grade classes in 14 schools in China. A mixed-methods design was used. Quantitative data on learner knowledge gain were collected from the learners. Qualitative data included lesson observation fieldnotes, social-media posts, and interview responses and were gathered from the pre-service teachers. Results: Learners in the Health-First schools gained more knowledge than those in the Comparison schools (t26 = 2.92, p =.007, Cohen's d = 1.10). Qualitative evidence was triangulated using a Health-First vs. Comparison contrasting approach with open-, axial-, and selective-coding to generate themes. The themes were Confidence in Doubt, Lesson Plans to the Rescue, Professional Development is Necessary But..., and Student Learning Save the Day! A grounded theory was developed using the themes and interpreted using the Interconnection Model of Teacher Professional Growth. Conclusion: Breaking CSZ requires a synergistic effort with carefully designed professional development, detailed lesson plans, an effective support network, and, most important of all, a powerful curriculum that can elicit observable and measurable learner achievement. [ABSTRACT FROM AUTHOR]

Purpose: It has been acknowledged in physical education (PE) that knowledge empowers learners to develop a physically active lifestyle In this study, we consider Cognitive Load Theory (CLT) as a valuable extension of the constructivist learning theory to help articulate the role of three pivotal instructional factors, content knowledge, learners, and instructional process, in learning fitness knowledge in PE. Guided by CLT, this study was intended to identify middle school students' cognitive architecture about aerobic and anaerobic concepts and pedagogical factors that might enhance or limit scientific conceptualization. Methods: We employed a mixed-methods approach. A total of 291 students randomly drawn from the 24 schools provided data on conceptual knowledge levels via standardized test and conceptual structures of understanding via semi-structured interviews about the aerobic/anaerobic concepts. Results: Results from integrated quantitative and qualitative analyses reveal the role of task element interactivity as a function of conceptualization in the students' cognitive architecture. The students lack the understanding that aerobic and anaerobic concepts are associated with the concepts of complex metabolic systems that dictate the energy pathways experienced in physical activity. Their understandings are characterized by a tendency of overly simplifying the complex conceptions for convenient schema activation. The simplified conception is likely to prohibit their understanding from becoming consistent with the science. The findings suggest that teachers should anticipate lack of understanding of knowledge connectivity when teaching fitness concepts and establish the task element interactivity with enhanced clarity to facilitate knowledge learning. Conclusion: Consistent with the constructivist learning theory, the findings inform us that teaching complex fitness concepts require the teacher to connect prior knowledge as a prerequisite to activate relevant cognitive architecture and actively build connections between the prior knowledge and the to-be learned concepts. PE curriculum designers and teachers should anticipate the complex challenges in teaching the aerobic and anaerobic concepts because of their connections to other concepts associated with human energy systems such as intensity and oxygen supply. [ABSTRACT FROM AUTHOR]

A flexible polyurethane elastomer (PUE) is studied, and the improved impact-resistant performance is revealed. Compressive stress–strain curves over a wide loading rate range were derived. Under static loading, the rubbery-like characteristics are demonstrated, which are flexible and hyperelastic, to process a large strain of about 60% followed by full recovery upon unloading. Under high-rate loadingcompared with the mechanical data of polyurethane elastomer (PUE) and polyurea (PUA) materials in the literature. Orderly parallel deformation bands were formed from carrying a large strain. The fibrils were found between deformation bands for enhancing the yield/plateau stress. A considerable plastic zone ahead of propagating crack with numerous crazes and microcracks was produced for realizing the dynamic strain energy absorption. This work presents a scientific innovation for developing outstanding impact-resistant polyurethane elastomers for transparent protection engineering. [ABSTRACT FROM AUTHOR]

[Display omitted] • A selection strategy for base-period images of spatio-temporal fusion was proposed. • The spatio-temporal inconsistency between field samples and images was reduced. • The estimation accuracy of grassland aboveground biomass was improved. The accurate estimation of the aboveground biomass (AGB) is crucial for the sustainable utilization and management of grassland resources. Spatio-temporal inconsistencies between field samples and satellite images are major source of error in the estimation of grassland AGB. To solve this problem, this study selected the Three Rivers Headwater Region as the study area and proposed a selection strategy for base-period images of spatio-temporal fusion that was suitable for use at a large spatial scale in which cloud-free images are difficult to obtain. The spatial and temporal adaptive reflectance fusion model (STARFM) based on the selection strategy was used to generate a synthetic Normalized Difference Vegetation Index (NDVI) dataset with high spatial-temporal resolution by using the maximum value composite of GF-1 NDVI and MODIS NDVI to enhance the spatial-temporal quality of the images for field-scale application. Three estimation models for grassland AGB were then constructed by the random forest algorithm using synthetic NDVI, MODIS NDVI, GF-1 NDVI respectively, together with ancillary data. Following this, the estimation model with the highest accuracy was used to generate a 16-m eight-day time-series AGB in the growing season. The results showed: (1) The synthetic NDVI was correlated closely with the observed GF-1 NDVI, with an average R of 0.825 and a RMSE of 0.087. The temporal trend of the synthetic NDVI for each grassland type was highly consistent with that of the MODIS NDVI in the growing season with a correlation higher than 0.9. (2) The synthetic NDVI reduced the spatial difference between field samples and images to 16-fold, and the temporal difference was controlled to within four days under ideal conditions. (3) The synthetic NDVI improved the estimation accuracy of grassland AGB by about 15.9% and 19.7% (R2), and 13.7% and 17.5% (RMSE) relative to MODIS NDVI and GF-1 NDVI, respectively. (4) The time-series AGB revealed accurately the spatial distribution of and seasonal temporal variations in the grassland biomass. The results of this study may serve as scientific guidance for timely monitoring of grassland conditions and precise management of grassland resources in China. [ABSTRACT FROM AUTHOR]

Ultrasonic guided waves (UGWs) in water-filled pipes are subject to more severe dispersion and attenuation than vacant pipes, posing significant challenges for defect identification and localization. To this end, a novel sparse signal decomposition method called orthogonal matching pursuit based on dispersion and multi-mode (DMOMP) was proposed, which utilizes the second-order asymptotic solution of dispersion curves and the conversion characteristics of asymmetric UGWs in the defect contact stage to reconstruct the dispersive signals and converts the time-domain dispersive signals to distance-domain non-dispersive signals by dispersion compensated time-distance mapping. The synthesized simulation results indicate that DMOMP not only exhibits higher reconstruction accuracy compared to OMP, but also reveals more accurate and stable mode recognition and localization compared to DOMP, which only considers the dispersion under perturbation and noise. In addition, the UGW testing experimental results of water-filled pipes verify the effectiveness of DMOMP, the localization accuracies of three feature signals (defct 1, defct 2 and end echo) with DMOMP are 99.10%, 98.72% and 98.36%, respectively, and the average localization accuracy of DMOMP is as high as 98.73%. [ABSTRACT FROM AUTHOR]

Inhibition of CYP enzymes is thought to be the most common cause of drug–drug and/or herb–drug interactions. To characterize the inhibition of CYP enzymes activities by chemicals, enzyme inhibition kinetic experiments are usually carried out. The purpose of this letter is to call attention to evaluate the enzyme inhibition kinetics in drug–drug interactions. [ABSTRACT FROM AUTHOR]

Oridonin (ORI), the major pharmacological component extracted from a traditional Chinese medicine, possesses a beneficial effect on myocardial ischemia/reperfusion (I/R) injury. However, the underlying molecular mechanism by which ORI effects take place is not completely known. Thus, whether ORI works via downregulating oxidative stress and nod-like receptor protein-3 (NLRP3) inflammasome pathway was investigated in this study. Mice underwent surgery to induce myocardial I/R injury, and some were administered ORI (10 mg/kg/day) pretreatment, while others were not. The myocardial enzymes' levels, infarct area, and inflammatory injury were measured. The activation situation of oxidative stress and NLRP3 inflammasome was also detected. We found that ORI pretreatment significantly alleviated CK-MB and cTnI levels and infarct size induced by I/R. ORI mitigated the inflammatory injury by decreasing the pathological damage and lowering TNF-α, IL-1β, and IL-18 levels. Moreover, the SOD1 and eNOS levels were significantly increased by ORI, while MDA and iNOS levels were relatively decreased. The oxidative stress was reversed using ORI pretreatment. Importantly, NLRP3 inflammasome pathway was also inhibited by ORI, as reflected by the lower protein levels of NLRP3, caspase-1, and IL-1β. In conclusion, ORI alleviates myocardial injury induced by I/R via inhibiting the oxidative stress and NLRP3 inflammasome pathway. [ABSTRACT FROM AUTHOR]

• The inhibition risk of shikonin on UGT enzymes was firstly investigated. • Shikonin significantly inhibited UGT1A1, UGT1A3, UGT1A9/PROG, and UGT2B7/AZTG activities in human and rat liver microsomes. • Shikonin exhibited no time-dependent inhibition on UGT activities. • Shikonin displayed competitive inhibition on UGT isoforms. Shikonin, a natural red colorant, is widely used for food garnishment and cosmetic ingredient in the world. Shikonin also possesses a variety of pharmacological actions, including anti-inflammation and anti-cancer activities. However, little is known about its effects on the UDP-glucuronosyltransferases (UGT) activity. Therefore, the aim of this study was to evaluate the effect of shikonin on the UGT1A1, UGT1A3, UGT1A6, UGT1A9 and UGT2B7 activities via the human and rat liver microsomal assay and cocktail approach. The results showed shikonin inhibited human and rat liver microsomal UGT activity only in a dose-dependent manner. The further enzyme kinetic studies demonstrated that shikonin was not only a competitive inhibitor of human UGT1A1, UGT1A9, and UGT2B7, but also presented competitive inhibition on rat UGT1A1 and AZTG reactions. In conclusion, shikonin as a reversible inhibitor of UGT enzyme has a high-risk potential to cause the possible toxicity, especially drug-drug or food-drug interactions. [ABSTRACT FROM AUTHOR]

The increasing frequency of global drought events poses a significant threat to the stability of grassland ecosystems' functionality. The Inner Mongolian grasslands stand out as one of the world's most drought-prone regions, facing elevated drought risks compared to other biomes. An in-depth comprehension of the impact of drought on grassland ecosystems is paramount for their long-term sustainability. Using the Standardized Precipitation Evapotranspiration Index (SPEI) from 1982 to 2018, this study identified various drought events within the Inner Mongolian grasslands, encompassing moderate drought, severe drought, and extreme drought. The resistance of the vegetation to the different drought conditions, assessed through net primary productivity (NPP) as a metric (reflecting its capacity to maintain its original level during drought periods), was examined. The research findings indicated that the period from 2001 to 2018 witnessed a substantial increase in both the frequency and the extent of drought events compared to the period from 1982 to 2000, particularly concerning severe and extreme droughts. The areas most severely impacted by extreme drought were the Xilingol League and the Alxa League. From 1982–2000 to 2001–2018, under moderate drought conditions, vegetation resistance exhibited a minor decrease in the central and eastern regions but experienced a slight increase in the western region. In contrast, under severe drought conditions, the western region saw a significant decrease in vegetation resistance. Remarkably, under extreme drought conditions, the western region showed a substantial increase in vegetation resistance, while the central and eastern regions experienced a slight decrease. Across all three drought conditions, as precipitation levels declined, the resistance of the meadow–steppe–desert ecosystems demonstrated a high–low–high distribution pattern. The temperate desert steppe exhibited a minimal vulnerability to drought, boasting resistance levels exceeding 0.9. Notably, extreme drought had the most pronounced impact on the temperate meadow steppe, temperate steppe, and temperate desert steppe, particularly within the temperate meadow steppe category. Given these findings, the authorities responsible for grassland management should prioritize regions characterized by frequent drought occurrences and low drought resistance, such as Ulanqab City, the Xilingol League, and the western part of Hulun Buir City. Safeguarding steppe ecosystems is of paramount importance for stabilizing vegetation productivity and land carbon sinks, especially under the anticipated exacerbation of climate conditions in the future. [ABSTRACT FROM AUTHOR]

Tunnel lining falling blocks can cause great threats to traffic safety, resulting in traffic interruptions or speed limits and endangering operational safety. Traditional lining disease remediation measures have low efficiency and high costs and are time consuming. Combining the research methods used in the literature, indoor testing, and model experiments, a very normal material, namely, polyurea spray film material, is proposed as a means by which to remediate the lining falling block disease in tunnels. A 1 : 1 tunnel lining structure model was established at the site, and four experimental conditions were tested. The experiments revealed that the tensile stress was less than the tensile strength and that no tensile fracture occurred in the polyurea spray film material under the joint action of the block's self-weight and aerodynamic loads. Factors such as side seam treatment, surface sanding, and spray temperature may influence the bond strength of the polyurea spray film material. In order to remediate the issue of lining blocks falling, we recommended increasing the bond strength between the spray film material and the concrete or increasing the thickness of the polyurea spray film material. [ABSTRACT FROM AUTHOR]

This paper presents a new topology optimization technique for the design of compliant mechanisms that are efficient in transferring motion, force, or energy while being sufficiently strong to resist yield or fatigue failure. Generally, flexure hinges are efficient in transferring motion, force, or energy but are weak in resisting yield or fatigue failure while slender beams are relatively inefficient but strong. Thus, our philosophy is that a compliant mechanism may benefit from the above complimentary properties of flexure hinges and slender beams if they are connected and sized in a rational way. This requires a design approach with both flexure hinges and beams as constructional elements, and the design approach should include criteria on both efficiency and strength. Therefore, in the proposed technique, a mixed mesh of flexure hinges and beams was employed to discretize the design domain, and their connectivity, locations, and sizes were simultaneously determined to fulfill both the so-called stiffness-flexibility criterion (for efficiency) and a newly proposed input stroke criterion (for strength). The input stroke of a compliant mechanism, defined per the von-Mises yield criterion, is inversely proportional to the maximum stress per input displacement and represents the mechanism's maximum input displacement before yield failure. Both theoretical explorations and design examples demonstrate that the strength of compliant mechanisms can be significantly improved without compromising the efficiency, and trade-off designs that are better balanced between strength and efficiency can be obtained. [ABSTRACT FROM AUTHOR]

Cell-in-cell structure is prevalent in human cancer, and associated with several specific pathophysiological phenomena. Although cell membrane adhesion molecules were found critical for cell-in-cell formation, the roles of other membrane components, such as lipids, remain to be explored. In this study, we attempted to investigate the effects of cholesterol and phospholipids on the formation of cell-in-cell structures by utilizing liposome as a vector. We found that Lipofectamine-2000, the reagent commonly used for routine transfection, could significantly reduce entotic cell-in-cell formation in a cell-specific manner, which is correlated with suppressed actomyosin contraction as indicated by reduced β-actin expression and myosin light chain phosphorylation. The influence on cell-in-cell formation was likely dictated by specific liposome components as some liposomes affected cell-in-cell formation while some others didn't. Screening on a limited number of lipids, the major components of liposome, identified phosphatidylethanolamine (PE), stearamide (SA), lysophosphatidic acid (LPA) and cholesterol (CHOL) as the inhibitors of cell-in-cell formation. Importantly, cholesterol treatment significantly inhibited myosin light chain phosphorylation, which resembles the effect of Lipofectamine-2000, suggesting cholesterol might be partially responsible for liposomes' effects on cell-in-cell formation. Together, our findings supporting a role of membrane lipids and cholesterol in cell-in-cell formation probably via regulating actomyosin contraction. [ABSTRACT FROM AUTHOR]

An innovative morphing scheme, i.e., dynamical chordwise retracting and stretching, has been proposed for flapping wings. Its aerodynamic effects have been investigated based on a plunging two-dimensional flat wing. The conclusive results suggest that the novel morphing scheme can help to enhance the power utilization efficiency of flapping wings in forward motions. Plunging wings equipped with the novel morphing scheme can generate more thrust for a given power consumption or consume less power for a given thrust generation compared with their non-morphing counterparts. Moreover, the morphing scheme tends to function more positively as the defined morphing amplitude increases. In the currently covered parameter spaces, the largest peak propulsive efficiency improvements induced by the morphing scheme are 12.3% at Re = 15 × 104 and 10.8% at Re = 5 × 104, respectively. Examination of the flow structures around the plunging wings reveals that dynamical chordwise retracting and stretching of the wing can ameliorate the vortex distribution, which could account for the propulsive property changes caused by the morphing scheme. The current study may have yielded an inspiring and prospective scheme for enhancing the propulsive capacity of micro-flapping-wing aerial and underwater robots. [ABSTRACT FROM AUTHOR]

• Light-scattering angular spectrum is proposed for high-resolution particle sizing. • A compacted and lens-free optical system is designed for LSAS sampling. • The particle size distribution is inversed with high accuracy (D KL < 0.05). • The sensor is low-cost and portable for in-situ aerosol contamination measurement. In the study of aerosols, great concern has been focused on the particle size distribution (PSD) as a crucial factor of the physical and chemical properties of the aerosols. There are strong and growing demands for on-line and in-situ aerosol analysis technologies, but existing portable aerosol sensors can hardly provide high-resolution and accurate PSD measurement with limited volume and cost. To address this challenge, we introduce the concept of a new optical aerosol sensing method using light-scattering angular spectrum (LSAS), which describes the angular dependence of the scattering light intensity. The key novelty is a compacted LSAS sampling module for collecting the scattering light up to the observing angles. According to the wide-range LSAS sampled by our sensor, high-resolution PSD is predicted by non-negative regularization inversion algorithm. To validate the performance of our sensor, monodisperse di-ethyl-hexyl-sebacate aerosols (DEHS) samples of different sizes and smokes of smoldering cotton rope were tested. The maximum relative error (RE) of LSAS was smaller than 12.02%, while the Kullback-Leibler Divergence (D KL) between inversed and reference PSDs were smaller than 0.05. Without using any particulate pre-separation module and optical lens, we build a novel low-cost and miniaturized sensor only composed of a mirror, a linear charge coupled device (CCD) and a semiconductor laser, which has significant potential for high-resolution aerosol sizing in routine field measurements outside a laboratory. [ABSTRACT FROM AUTHOR]