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The background of pipeline weld surface defect image is complex, and the defect size is small. Aiming at the small defect size in the weld image, which is easy to cause missed detection and false detection, a lightweight target detection algorithm based on improved YOLOv7 is proposed. Firstly, in the feature fusion network of YOLOv7, the detection ability of the algorithm to detect small and medium-sized targets in defect images is enhanced by adding a 160*160 small target detection head. Then, the convolution module in the backbone network and the feature fusion network is replaced by the depthwise separable convolution with less computational overhead, so as to effectively reduce the network calculation, parameter quantity and model volume. Finally, the loss function CIoU of YOLOv7 is optimized to EIoU loss function to accelerate the convergence speed of the model. The experimental results show that the defect detection mAP@0.5 based on the improved YOLOv7 algorithm can reach 72.2%, which is 11% higher than that of YOLOv7, and the model calculation amount and parameter amount are reduced by 75.6% and 60.3%, respectively. It can completely detect the small size defects and has a high degree of confidence, which can be effectively applied to the detection of small size defects on the surface of pipeline weld. [ABSTRACT FROM AUTHOR]

Fracture surface morphology, mechanical and hydraulic properties are related to fracture size. One of the core issues in the size effect is the representative elementary surface, which determines the size of the test specimens in the laboratory and facilitates the application of test results to the field. In this study, the size effect on surface morphology and permeability of rock fractures is investigated, and the representative elementary surface size for the surface morphology and the permeability was determined based on the asperity height data of fracture surfaces obtained by 3D laser scanning in the field. The roughness of fracture surfaces varies significantly at small fracture surface sizes. As the fracture surface size continues to increase, the fracture surface roughness tended toward a relatively stable state. The critical size for fracture surface roughness stability in the study, which is called the representative elementary surface, is 300–400 mm. The size effect on the permeability of rock fractures was investigated, and the results show that fracture permeability tended toward a relatively stable state with increasing fracture size, which was the same as the fracture surface roughness. The representative elementary surface size for fracture permeability is less than 100 mm in the study, which is also less than that for fracture surface roughness with the same coefficient of variation. This result indicated that a lower coefficient of variation might provide the best estimate of the representative elementary surface for fracture permeability compared with the fracture surface roughness. [ABSTRACT FROM AUTHOR]

How linguistic distance affects second language acquisition is a major concern in cross-language transfer research. However, no study has explored how systematic differences between Chinese and learners’ native language (L1) influences Chinese character, vocabulary, and grammar acquisition, or how these influences change as Chinese proficiency improves. To address this, we employed the World Atlas of Language Structures (WALS) index method to multidimensionally quantify the linguistic distance between Chinese and L1, and examined the effect of systematic linguistic distance on acquisition of Chinese character (Quasi-Experiment 1), vocabulary (Quasi-Experiment 2), and grammatical knowledge (Quasi-Experiment 3) in Chinese as a second language (CSL) learners with elementary, intermediate, and advanced Chinese proficiency levels. We examined a random sample of 58,240 CSL learners’ test scores from 24 different L1 backgrounds, and analyzed 2,250 CSL learners’ Chinese character, vocabulary, and grammar scores in each of the three quasi-experiments. We found that closer linguistic distance facilitated more favorable Chinese character and vocabulary acquisition at elementary, intermediate, and advanced Chinese proficiency levels, and that the influence of linguistic distance on CSL learners’ vocabulary acquisition tended to decrease as Chinese proficiency increased. Finally, linguistic difference did not significantly affect CSL learners’ grammar acquisition at elementary proficiency, but as Chinese proficiency improved, an L1 interference effect occurred among CSL learners with a short linguistic distance from Chinese, which hindered grammar acquisition. These results suggest that linguistic distance has differential proficiency-dependent effects on Chinese character, vocabulary, and grammar acquisition. [ABSTRACT FROM AUTHOR]

In eukaryotes, Maf1 is an essential and specific negative regulator of RNA polymerase (Pol) III. Pol III, which synthesizes 5S RNA and transfer RNAs (tRNAs), is suppressed by Maf1 under the conditions of nutrient starvation or environmental stress. Here, we identified M. oryzae MoMaf1, a homolog of ScMaf1 in budding yeast. A heterogeneous complementation assay revealed that MoMaf1 restored growth defects in the ΔScmaf1 mutant under SDS stress. Destruction of MoMAF1 elevated 5S rRNA content and increased sensitivity to cell wall agents. Moreover, the ΔMomaf1 mutant exhibited reduced vegetative growth, conidiogenesis, and pathogenicity. Interestingly, we found that MoMaf1 underwent nuclear-cytoplasmic shuffling, through which MoMaf1 accumulated in nuclei under nutrient deficiency or upon the interaction of M. oryzae with rice. Therefore, this study can help to elucidate the pathogenic molecular mechanism of M. oryzae. [ABSTRACT FROM AUTHOR]

Lupeol, curcumin, and quercetin are naturally occurring compounds present in plants, with some beneficial health effects. In the present study, organogel-based emulsions (o/w) were obtained from edible oils to increase their bioaccessibility and intestinal permeability. Particle size analysis, rheology test, optical microscopy, in vitro digestibility, and permeability of nutraceuticals by cell culture and UPLC-MS/MS were performed. Particle hydrodynamic diameters obtained in organogel-based emulsions loaded with nutraceuticals were <200 nm, polydispersity index was around 0.25–0.4, and zeta potential was about –19 to –25 mV. Droplets in emulsions presented spherical shapes and adjusted to the Herschel–Bulkley model. Interestingly, bioaccessibility and intestinal permeability of lupeol was increased compared with its crystalline form, opposite to the observed for curcumin and quercetin; therefore, organogel-based emulsions loaded with lupeol have potential for controlled oral delivery of this nutraceutical. [ABSTRACT FROM AUTHOR]

Multivariate hydrological series become nonstationary under the changing environment. In this paper, a new method is proposed to study the change in the dependence structure between runoff and sediment sequences. First, a moving cut transfer entropy is proposed to detect the sudden change point in the dependence structure between runoff and sediment. Then, the Gumbel copula with a new parameter estimation method (MEE) is employed to construct the dependence structure of runoff and sediment before or after the change point for situation with small samples. The new method is applied to the annual runoff and sediment discharge series in Xiliugou River, China. It is found that the dependence structure between runoff and sediment changed abruptly in 2000. The joint probabilistic characteristics of the annual runoff and sediment discharge during the period of 1960–1999 are built based on the values of RMSEs and AICs. The joint distribution of the annual runoff and sediment discharge during the period of 2000–2016 is constructed by the Gumbel copula with MEE. Moreover, the synchronous encounter probability of runoff and sediment decreases from 0.76 to 0.63, and the asynchronous encounter probability rises from 0.24 to 0.37, after the runoff and sediment discharge series presents a significant change in the dependence structure. [ABSTRACT FROM AUTHOR]

Stroke is a neurological disease responsible for significant morbidity and disability worldwide. However, there remains a dearth of effective therapies. The failure of many therapies for stroke in clinical trials has promoted the development of human cell-based models, such as brain organoids. Brain organoids differ from pluripotent stem cells in that they recapitulate various key features of the human central nervous system (CNS) in three-dimensional (3D) space. Recent studies have demonstrated that brain organoids could serve as a new platform to study various neurological diseases. However, there are several limitations, such as the scarcity of glia and vasculature in organoids, which are important for studying stroke. Herein, we have summarized the application of brain organoid technology in stroke research, such as for modeling and transplantation purposes. We also discuss methods to overcome the limitations of brain organoid technology, as well as future prospects for its application in stroke research. Although there are many difficulties and challenges associated with brain organoid technology, it is clear that this approach will play a critical role in the future exploration of stroke treatment. [ABSTRACT FROM AUTHOR]

Restoration of the normoglycemic state is the basic tenet of diabetes research. Nowadays, using nanoemulsion drug delivery systems represent an alternative effective tool in Type 2 diabetes mellitus management. We aimed to investigate the anti-diabetic potential of metformin nanoemulsion and mesenchymal stem cells (MSCs) therapy on streptozotocin (STZ)-induced diabetic rat model. Nanoemulsion formulation was prepared with oil phase (5%v/v), 1gm metformin with a hydrophilic surfactant, then characterized for particle size and zeta potential. Adult male albino rats were induced for diabetes with 60 mg/kg STZ and were classified into 4 groups: STZ control group; STZ+MET group (orally administered daily dose of metformin 18 mg/200 g b.wt.); STZ+MSCs group (mono-therapeutic dose of BM-MSCs 1×106 cells/rat) and STZ+Nano-MET group (daily intraperitoneal dose of metformin nanoemulsion 18 mg/kg b.wt.). After 8 weeks, relative expression levels of hepatic IRS-1, AKT, Bcl-2, and Bax were assessed by qPCR. Also, histopathological investigations were performed. We reported cytoplasmic vacuolation, tissue necrosis, dilated blood sinusoid and congested hepatic vein in STZ group. Experimental animals either treated with metformin nanoemulsion or the mono-therapeutic dose of MSCs exhibited significant up-regulation in IRS-1/AKT pathway and Bcl-2 gene expression levels, as well as significant repression in Bax mRNA levels, besides a remarkable amelioration in a hepatic histological organization. Conclusion: Nano-MET holds an anti-diabetic potential that clearly surpasses metformin via affecting the insulin signaling pathway and apoptotic gene expression. [ABSTRACT FROM AUTHOR]

Aims: Knowledge of the Trichoderma taxa is important for both control efficiency and environmental conservation. Therefore, the objective of this study is to isolate and identify Trichoderma species from various rhizosphere soil samples using phenotypic and molecular characterization. Methodology and results: Native Trichoderma spp. were isolated from agricultural fields in 17 sites from seven states of Malaysia. These isolates were characterized via morphological observation and molecular phylogenetic analysis based on the translation elongation factor-1α (tef1-α) gene. About 42 isolates were classified into eight Trichoderma species, which are Trichoderma asperellum, T. hamatum, T. harzianum, T. koningiopsis, T. rodmanii, T. spirale, T. viride and T. virens. Comparison of DNA sequences of tef1-α showed that the isolates were 98-100% similar to respective Trichoderma species from GenBank, thus confirming the fungal identity. Phylogenetic trees of maximum likelihood (ML) dataset of tef1-α inferred that the isolates were clustered according to species. Conclusion, significance and impact of study: Findings in the present study will be beneficial for the purposes of biodiversity conservation and plant disease management using biocontrol agents. [ABSTRACT FROM AUTHOR]

Featured Application: This work can be applied to the development of new axle materials and to the high-cycle fatigue testing of materials at low temperatures. Railway vehicles are being exposed with increasing frequency to conditions of severe heat and cold because of changes in the climate. Trains departing from Asia travel to Europe through the Eurasian continent and vice versa. Given these circumstances, the mechanical properties and performance of vehicle components must therefore be evaluated at lower and higher temperatures than those in current standards. In this study, specimens were produced from a commercial freight train axle made of manganese steel and subjected to high-cycle fatigue tests at −60, −30, and 20 °C. The tests were conducted using an ultrasonic fatigue tester developed to study fatigue at low temperatures. Charpy impact testing was performed over the temperature range of −60 to 60 °C to measure the impact absorption energy of the axle material. The material showed a fatigue limit above 2 million cycles at each temperature; the lower the test temperature, the greater the fatigue limit cycles. The impact absorption energy at −60 °C was 81% less compared to the value at 20 °C. The axle material became completely brittle in the temperature range of −30 to −40 °C. [ABSTRACT FROM AUTHOR]

The efficacy of oily components is often difficult to evaluate due to their incompatibility with most models. Here, we emulsified adlay bran oil (ABO), processed it to a nanoscale, and investigated its anti‐hyperpigmentation efficacy, assessed for its inhibitory effects against tyrosinase activity and melanin production, in an in vitro system (mouse melanoma B16F10 cells) and an in vivo system (zebrafish embryos). ABO induced dose‐dependent reductions in tyrosinase activity and melanin production in both the melanoma cells and zebrafish, without affecting viability. The efficacy of ABO was strongly influenced by emulsion particle size in the zebrafish but not in the cells. These results indicate that ABO has potential as a tyrosinase inhibitor and anti‐hyperpigmentation agent and that the emulsion system is an effective method for delivering the bioactive components of ABO to living systems that could be utilized for other oily components. [ABSTRACT FROM AUTHOR]

Climate simulations with more accurate process-level representation at finer resolutions (<100 km) are a pressing need in order to provide more detailed actionable information to policy makers regarding extreme events in a changing climate. Computational limitation is a major obstacle for building and running high-resolution (HR, here 0.25 ∘ average grid spacing at the Equator) models (HRMs). A more affordable path to HRMs is to use a global regionally refined model (RRM), which only simulates a portion of the globe at HR while the remaining is at low resolution (LR, 1 ∘). In this study, we compare the Energy Exascale Earth System Model (E3SM) atmosphere model version 1 (EAMv1) RRM with the HR mesh over the contiguous United States (CONUS) to its corresponding globally uniform LR and HR configurations as well as to observations and reanalysis data. The RRM has a significantly reduced computational cost (roughly proportional to the HR mesh size) relative to the globally uniform HRM. Over the CONUS, we evaluate the simulation of important dynamical and physical quantities as well as various precipitation measures. Differences between the RRM and HRM over the HR region are predominantly small, demonstrating that the RRM reproduces the precipitation metrics of the HRM over the CONUS. Further analysis based on RRM simulations with the LR vs. HR model parameters reveals that RRM performance is greatly influenced by the different parameter choices used in the LR and HR EAMv1. This is a result of the poor scale-aware behavior of physical parameterizations, especially for variables influencing sub-grid-scale physical processes. RRMs can serve as a useful framework to test physics schemes across a range of scales, leading to improved consistency in future E3SM versions. Applying nudging-to-observations techniques within the RRM framework also demonstrates significant advantages over a free-running configuration for use as a test bed and as such represents an efficient and more robust physics test bed capability. Our results provide additional confirmatory evidence that the RRM is an efficient and effective test bed for HRM development. [ABSTRACT FROM AUTHOR]

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Background: Pancreatic extracorporeal shock wave lithotripsy (P-ESWL) is the first-line therapy for large pancreatic duct stones. Although it is a highly effective and safe procedure for the fragmentation of pancreatic stones, it is still not complication-free. Just like endoscopic retrograde cholangiopancreatography (ERCP), pancreatitis is the most common complication. To date, nonsteroidal anti-inflammatory drugs (NSAIDs) have proven to be the only effective prophylactic medication for post-ERCP pancreatitis and the European, American and Japanese Society for Gastrointestinal Endoscopy guidelines have recommended prophylactic rectally administered indomethacin for all patients undergoing ERCP. Given the little research about effective prevention for post P-ESWL pancreatitis, we aim to determine whether rectally administered indomethacin can reduce post-ESWL-pancreatitis.Methods/design: The RIPEP study is a prospective, randomized, double-blinded, placebo-controlled trial. One thousand three hundred and seventy patients with chronic pancreatitis and pancreatic stones (>5 mm in diameter) treated with P-ESWL at Changhai Hospital will be randomly allocated to rectally administered indomethacin or placebo therapy before the procedure. The primary endpoint is the incidence of post-ESWL pancreatitis. Secondary endpoints include the severity of pancreatitis, occurrence rate of asymptomatic hyperamylasemia and other complications.Discussion: The RIPEP trial is designed to show that rectally administered indomethacin reduces the development and severity of post-ESWL pancreatitis and benefits patients treated with P-ESWL.Trial Registration: ClinicalTrials.gov, ID: NCT02797067 . Registered on 17 November 2016. [ABSTRACT FROM AUTHOR]

Empirical research on the effect of family size on child education is complicated by the endogeneity of family size. This study exploits plausibly exogenous changes in family size caused by China's population control policy to estimate the causal relationship between family size and child education outcomes. The results show that, compared to an only child, a person with an additional sibling will have an approximate seventeen percentage points lower likelihood of completing middle school in China. Separate regressions across individual characteristics reveal that much of this negative effect appears to be driven by the cohorts born in earlier years after the policy, and children with the highest birth order within a family. [ABSTRACT FROM AUTHOR]

Rice is a staple food for more than half of the worldwide population and is also a model species for biological studies on monocotyledons. Through a team effort, Chinese scientists have made rapid and important progresses in rice biology in recent years. Here, we briefly review these advances, emphasizing on the regulatory mechanisms of the complex agronomic traits that affect rice yield and grain quality. Progresses in rice genome biology and genome evolution have also been summarized. [ABSTRACT FROM AUTHOR]

The objective of this paper is to investigate the effects of laminate scheme, crack ratio (a/h) and crack position (L1/L) on the free vibration and lateral buckling of a cantilever slender rectangular beam such as an airplane wing or a wind turbine blade with a single edge crack. The local flexibility approach is adopted to model the crack, based on linear fracture mechanics and the Castigliano theorem. The governing matrix equations for free vibration and buckling load are derived from the standard beam element and cracked beam element combined with the local flexibility concept. The results are obtained numerically using the finite element method, based on the energy approach and are given for crack ratios up to 0.5 at crack positions up to 0.9 ratio. Polynomial approximation for displacements gives results with reasonable accuracy. [ABSTRACT FROM AUTHOR]

Over the next generation or two, America's older, largely white population will increasingly be replaced by today's disproportionately poor minority children. All future growth will come from populations other than non-Hispanic whites as America moves toward a majority-minority society by 2043. This so-called Third Demographic Transition raises important implications about changing racial boundaries in the United States, that is, about the physical, economic, and sociocultural barriers that separate different racial and ethnic groups. America's racial transformation may place upward demographic pressure on future poverty and inequality as today's disproportionately poor and minority children grow into adult roles. Racial boundaries will be reshaped by the changing meaning of race and ethnicity, shifting patterns of racial segregation in neighborhoods and the workplace, newly integrating (or not) friendship networks, and changing rates of interracial marriage and childbearing. The empirical literature provides complicated lessons and offers few guarantees that growing racial diversity will lead to a corresponding breakdown in racial boundaries-that whites and minorities will increasingly share the same physical and social spaces or interact as coequals. How America's older population of elected officials and taxpayers responds today to America's increasingly diverse population will provide a window to the future, when today's children successfully transition (or not) into productive adult roles. Racial and ethnic inclusion will be reshaped by changing ethnoracial inequality, which highlights the need to invest in children-now. [ABSTRACT FROM AUTHOR]

ording to the distribution characteristics of equivalent plastic strain (PEEQ) in radial-axial ring rolling, the plastic deformation zones in cross section were established. A 3D rigid-viscoplastic finite element model (FEM) which was controlled adaptively was applied to investigate defects that occurred during ring rolling under ABAQUS software. PEEQ, stress, and temperature distributions in different deformation zones have been analyzed in this study. Strain peaks were found in the cross-section corners. Moreover, it was investigated that non-uniform strain, stress, and temperature distributions in the ring tend to cause non-uniform microstructure and properties. Therefore, forming defects and microstructure damage would appear in cross-section corners due to the high-strain deformation. Based on the new developed FEM of the radial-axial ring-rolling process and comprehensive numerical simulations, the size effects of feed rate and lubrication conditions on strain and temperature distributions and their uniformity were investigated by 3D coupled thermomechanical FE simulation. The results have good agreement with experiment. The achievements of this study can provide basis for quality control and technical guidance. [ABSTRACT FROM AUTHOR]

This paper reported a dramatic channel incision (>10m in the deepest cut) during the past 10 y or so in the lower Pearl River, the second largest river in terms of water discharge in China. The channel incision had caused changes both in the channel geometry as well as in the river hydraulics. Also, the water exchange between the two major tributaries of the Pearl River, the Xijiang and Beijiang, had been significantly changed due to the channel incision. The rapid channel incision was principally the result of extensive sand mining in the lower Pearl River and the delta region due to the booming economy in the Pearl Delta region. Slight increase of water discharge and significant decrease of sediment load since the early 1990s in both the Xijiang and Beijiang also likely contributed to the observed dramatic river bed downcutting to some extent. This has important implications for river management, as the large Chinese rivers have seen a dramatic depletion of sediment fluxes due to the combined effects of declining rainfall, dam constructions, water diversion, reforestation and afforestation, and sediment mining over the recent decades. [ABSTRACT FROM AUTHOR]

A CAD application tool kit interfacing with a Unigraphics (UG) system was developed for disintegrating large and complex rapid prototyping objects into smaller and simpler components which can be fabricated by a rapid prototyping system. As the core of the tool kit, the algorithm of such disintegration is described in detail in this paper. The algorithm combines the flat planar parting method and feature-based volume decomposition. Due consideration is also given to the optimisation of the surface accuracy, the build time, and the strength and number of segments generated. Based on the algorithm and the CAD application tool kit, the disintegration of two RP objects was realised in a selective laser sintering system. [ABSTRACT FROM AUTHOR]

Develops a semantic framework for the multilevel security-relational model with tuple-level labeling. Classification of the information content of relational databases by atomic decomposition; Definition of filtering functions; Definition of multilevel secure relational model; Validity of multilevel relational databases; Discussion of an update semantics of the multilevel relational model.

In order to study the wear characteristic of a centrifugal pump at different mass concentrations, simulation and experimental research were carried out. The simulation was based on the DPM (discrete phase model) to complete the coupling of particles and the flow field. The experimental research included a performance test and a wear test. Through the comparison of the simulation and experimental research results, the relationship between the particle movement and the wear was analyzed, and the flow field was analyzed through the energy gradient theory. The energy gradient and the particle movement were combined to explain the wear characteristics. When the particles entered the impeller flow area, they directly hit the leading edge of the blade and the hub wall. The particles were sinking due to the flow field, which caused the particles to accumulate near the hub and the pressure surface. These places were at the most severely worn wall. The farther away from the axis the position was, the greater the relative velocity difference between the particles and the wall was, so that wear occurred first in these places. The low-energy properties near the hub made particles gather there, which was also the most serious cause of hub wear. [ABSTRACT FROM AUTHOR]

Food and feed laboratories share several similarities when facing the implementation of liquid-chromatographic analysis. Using the experience acquired over the years, through application chemistry in food and feed research, selected analytes of relevance for both areas were discussed. This review focused on the common obstacles and peculiarities that each analyte offers (during the sample treatment or the chromatographic separation) throughout the implementation of said methods. A brief description of the techniques which we considered to be more pertinent, commonly used to assay such analytes is provided, including approaches using commonly available detectors (especially in starter labs) as well as mass detection. This manuscript consists of three sections: feed analysis (as the start of the food chain); food destined for human consumption determinations (the end of the food chain); and finally, assays shared by either matrices or laboratories. Analytes discussed consist of both those considered undesirable substances, contaminants, additives, and those related to nutritional quality. Our review is comprised of the examination of polyphenols, capsaicinoids, theobromine and caffeine, cholesterol, mycotoxins, antibiotics, amino acids, triphenylmethane dyes, nitrates/nitrites, ethanol soluble carbohydrates/sugars, organic acids, carotenoids, hydro and liposoluble vitamins. All analytes are currently assayed in our laboratories. [ABSTRACT FROM AUTHOR]