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中学生英语 2024年第11期 31-32页

作者： brian S.McGrath 陈佳(译) 不详武汉市光谷五小

让更多的电动汽车上路的竞赛正在进行中。但根据2021年的一项调查,超过一半的美国成年人不希望逐步淘汰燃油汽车。让我们来看看国外学生的看法。

关键词：燃油汽车电动汽车逐步淘汰成年人

Clinical validity and utility of genetic risk scores in prostate cancer

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Asian Journal of Andrology 2016年第4期18卷 509-514页

作者： brian t Helfand James Kearns Carly Conran Jianfeng Xu Department of Surgery NorthShore University HealthSystem Program for Personalized Cancer Care Evanston IL 60201 USA.

Current issues related to prostate cancer （PCa） clinical care （e.g., over-screening, over-diagnosis, and over-treatment of nonaggressive PCa） call for risk assessment tools that can be combined with family history （FH） to stratify disease risk among men in the general population. Since 2007, genome-wide association studies （GWASs） have identified more than 100 SNPs associated with PCa susceptibility. In this review, we discuss （1） the validity of these PCa risk-associated SNPs, individually and collectively; （2） the various methods used for measuring the cumulative effect of multiple SNPs, including genetic risk score （GRS）; （3） the adequate number of SNPs needed for risk assessment; （4） reclassification of risk based on evolving numbers of SNPs used to calculate genetic risk, （5） risk assessment for men from various racial groups, and （6） the clinical utility of genetic risk assessment. In conclusion, data available to date support the clinical validity of PCa risk-associated SNPs and GRS in risk assessment among men with or without FH. PCa risk-associated SNPs are not intended for diagnostic use; rather, they should be used the same way as FH. Combining GRS and FH can significantly improve the performance of risk assessment. Improved risk assessment may have important clinical utility in targeted PCa testing. However, clinical trials are urgently needed to evaluate this clinical utility as well as the acceptance of GRS by patients and physicians.

关键词： genetic risk score prostate cancer pyramid model single nucleotide polymorphisms

A Review on the Management of Biliary Complications after Orthotopic Liver transplantation

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Journal of Clinical and translational Hepatology 2019年第1期7卷 61-71页

作者： brian t.Moy John W.Birk Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

Orthotopic liver transplantation is the definitive treatment for end-stage liver disease and hepatocellular *** complications are the most common complications seen after transplantation,with an incidence of 10-25%.these complications are seen both in deceased donor liver transplant and living donor liver *** treatment of biliary complications with endoscopic retrograde cholangiopancreatography(commonly known as ERCP)has become a mainstay in the management *** success rate has reached 80%in an experienced endoscopist's *** unsuccessful with ERCP,percutaneous transhepatic cholangiography can be an alternative *** recognition and treatment has been shown to improve morbidity and mortality in post-liver transplant *** focus of this review will be a learned discussion on the types,diagnosis,and treatment of biliary complications post-orthotopic liver transplantation.

关键词： Biliary tract complication Orthotropic liver transplantation Stricture Bile leak

A study of real-world micrograph data quality and machine learning model robustness

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npj Computational Materials 2021年第1期7卷 1463-1473页

作者： Xiaoting Zhong brian Gallagher Keenan Eves Emily Robertson t.Nathan Mundhenk t.Yong-Jin Han Materials Science Division Lawrence Livermore National LaboratoryLivermoreCAUSA Center for Applied Scientific Computing Lawrence Livermore National LaboratoryLivermoreCAUSA Defense technologies Engineering Division Lawrence Livermore National LaboratoryLivermoreCAUSA Computational Engineering Division Lawrence Livermore National LaboratoryLivermoreCAUSA

Machine-learning(ML)techniques hold the potential of enabling efficient quantitative micrograph analysis,but the robustness of ML models with respect to real-world micrograph quality variations has not been carefully *** collected thousands of scanning electron microscopy(SEM)micrographs for molecular solid materials,in which image pixel intensities vary due to both the microstructure content and microscope instrument *** then built ML models to predict the ultimate compressive strength(UCS)of consolidated molecular solids,by encoding micrographs with different image feature descriptors and training a random forest regressor,and by training an end-to-end deep-learning(DL)*** show that instrument-induced pixel intensity signals can affect ML model predictions in a consistently negative *** a remedy,we explored intensity normalization *** is seen that intensity normalization helps to improve micrograph data quality and ML model robustness,but microscope-induced intensity variations can be difficult to eliminate.

关键词： instrument image eliminate

Scale dependence of direct shear tests

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Chinese Science Bulletin 2009年第23期54卷 4337-4348页

作者： ZHOU Qiang SHEN Hayley H HELENBROOK brian t ZHANG HongWu Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China Department of Civil and Environmental Engineering Clarkson University Potsdam NY 13699-5710 USA Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699-5725 USA

Direct shear test has been widely used to measure the shear strength of soils and other particulate materials in industry because of its simplicity. However, the results can be dependent on the specimen size. the AStM (American Society for testing and Materials) publications suggest that for testing soils the shear box should be at least ten times the diameter of the largest particle and the height of the box should be no more than half of its diameter. these guidelines are empirically based. A series of two-dimensional numerical direct shear tests are performed to investigate this scaling effect. By analyzing the bulk friction, particle translation and rotation, percentage of sliding, average volume (area) and shear strain and the evolution of the shear band, we find that the traditional guidelines for direct shear tests are questionable. Scaling dependency of bulk friction on the property of granular materials is clearly present. Our current analysis points out that the scaling effects can vary significantly depending on the particle properties other than their sizes. Of all the parameters we observed, particle rotation appears to have a decisive correlation with the bulk friction. Formation of a shear band is universal. As the shearing progresses, particle rotation begins to concentrate near the shear plane. By defining the width of a shear band as the standard deviation of the distribution of translational gradient or the standard deviation of the distribution of particle rotation, quantitative evolutions of shear band are presented. Both measures of the shear band width dropped rapidly during pre-failure stage. After peak stress both measures begin to approach steady state as the bulk friction stabilizes to the residual stage. these observations suggest that structure formation inside the shear band controls the scaling effect.

关键词：直接剪切试验测试土力学土工试验

Explainable machine learning in materials science

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npj Computational Materials 2022年第1期8卷 1951-1969页

作者： Xiaoting Zhong brian Gallagher Shusen Liu Bhavya Kailkhura Anna Hiszpanski t.Yong-Jin Han Materials Science Division Lawrence Livermore National LaboratoryLivermoreCAUSA Center for Applied Scientific Computing Lawrence Livermore National LaboratoryLivermoreCAUSA

Machine learning models are increasingly used in materials studies because of their exceptional ***,the most accurate machine learning models are usually difficult to *** to this problem lie in explainable artificial intelligence(XAI),an emerging research field that addresses the explainability of complicated machine learning models like deep neural networks(DNNs).this article attempts to provide an entry point to XAI for materials *** are defined to clarify what explain means in the context of materials *** works are reviewed to show how XAI helps materials science *** and opportunities are also discussed.

关键词： explain learning plain

Reliable and explainable machine-learning methods for accelerated material discovery

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npj Computational Materials 2019年第1期5卷 186-194页

作者： Bhavya Kailkhura brian Gallagher Sookyung Kim Anna Hiszpanski t.Yong-Jin Han Center for Applied Scientific Computing Computing DirectorateLawrence Livermore National LaboratoryLivermoreCAUSA Materials Science Division Physical and Life Sciences DirectorateLawrence Livermore National LaboratoryLivermoreCAUSA

Despite ML’s impressive performance in commercial applications,several unique challenges exist when applying ML in materials science *** such a context,the contributions of this work are ***,we identify common pitfalls of existing ML techniques when learning from underrepresented/imbalanced material ***,we show that with imbalanced data,standard methods for assessing quality of ML models break down and lead to misleading ***,we find that the model’s own confidence score cannot be trusted and model introspection methods(using simpler models)do not help as they result in loss of predictive performance(reliability-explainability trade-off).Second,to overcome these challenges,we propose a general-purpose explainable and reliable machine-learning ***,we propose a generic pipeline that employs an ensemble of simpler models to reliably predict material *** also propose a transfer learning technique and show that the performance loss due to models’simplicity can be overcome by exploiting correlations among different material properties.A new evaluation metric and a trust score to better quantify the confidence in the predictions are also *** improve the interpretability,we add a rationale generator component to our framework which provides both model-level and decision-level ***,we demonstrate the versatility of our technique on two applications:(1)predicting properties of crystalline compounds and(2)identifying potentially stable solar cell *** also point to some outstanding issues yet to be resolved for a successful application of ML in material science.

关键词： explain overcome simpler

Drought Stress and Preharvest Aflatoxin Contamination in Agricultural Commodity: Genetics, Genomics and Proteomics

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Journal of Integrative Plant Biology 2008年第10期50卷 1281-1291页

作者： Baozhu Guo Zhi-Yuan Chen R. Dewey Lee brian t. Scully Crop Protection and Management Research Unit Agricultural Research Service US Department of Agriculture Tifton Georgia 31793 USA Department of Plant Pathology and Crop Physiology Louisiana State University Baton Rouge Louisiana 70803 USA Department of Crop and Soil Sciences University of Georgia Tifton Georgia 31793 USA

throughout the world, aflatoxin contamination is considered one of the most serious food safety issues concerning health. Chronic problems with preharvest afiatoxin contamination occur in the southern US, and are particularly troublesome in corn, peanut, cottonseed, and tree nuts. Drought stress is a major factor to contribute to preharvest afiatoxin contamination. Recent studies have demonstrated higher concentration of defense or stress-related proteins in corn kerners of resistant genotypes compared with susceptible genotypes, suggesting that preharvest field condition （drought or not drought） influences gene expression differently in different genotypes resulting in different levels of ＂end products＂： PR（pathogenesis-related） proteins in the mature kernels. Because of the complexity of Aspergillus-plant interactions, better understanding of the mechanisms of genetic resistance will be needed using genomics and proteomics for crop improvement. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy. Proteomic comparisons of corn kernel proteins between resistant or susceptible genotypes to Aspergillus flavus infection have identified stress-related proteins along with antifungal proteins as associated with kernel resistance. Gene expression studies in developing corn kernels are in agreement with the proteomic studies that defense-related genes could be upregulated or downregulated by abiotic stresses.

关键词： abiotic stress drought stress host resistance preharvest aflatoxin contamination.

Monitoring the Expression of Maize Genes in Developing Kernels under Droug ht Stress usingOligo-microarray

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Journal of Integrative Plant Biology 2010年第12期52卷 1059-1074页

作者： Meng Luo Jia Liu R. Dewey Lee brian t. Scully Baozhu Guo the University of Georgia Department of Crop and Soil Sciences Tifton GA 31793 USA J. Craig Venter Institute Rockville MD 20850 USA US D-epartment of Agriculture Agricultural Research Service Crop Protection and Management Research Unit Tifton GA 31793 USA

Preharvest aflatoxin contamination of grain grown on the US southeastern Coast Plain is provoked and aggravated by abiotic stress. the primary abiotic stress is drought along with high temperatures. the objectives of the present study were to monitor gene expression in developing kernels in response to drought stress and to identify drought-responsive genes for possible use in germplasm assessment. the maize breeding line tex6 was used, and gene expression profiles were analyzed in developing kernels under drought stress verses well-watered conditions at the stages of 25, 30, 35, 40, 45 d after pollination （DAP） using the 70 mer maize oligo-arrays. A total of 9 573 positive array spots were detected with unique gene IDs, and 7 988 were common in both stressed and well-watered samples. Expression patterns of some genes in several stress response-associated pathways, including abscisic acid, jasmonic acid and phenylalanine ammonia-lyase, were examined, and these specific genes were responsive to drought stress positively. Real-time quantitative polymerase chain reaction validated microarray expression data. the comparison between tex6 and B73 revealed that there were significant differences in specific gene expression, patterns and levels. Several defense-related genes had been downregulated, even though some defense-related or drought responsive genes were upregulated at the later stages.

关键词： CORN GENEtICS GENEtIC regulation in plants EFFECt of drought on plants EFFECt of stress on plants DNA microarrays AFLAtOXINS CROPS -- Postharvest technology

Use of non-timber forest products from invasive alien Prosopis species(mesquite) and native trees in South Africa: implications for management

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Forest Ecosystems 2015年第3期2卷 197-207页

作者： Ross t Shackleton David C Le Maitre brian W van Wilgen David M Richardson Centre for Invasion Biology Department of Botany and ZoologyStellenbosch University Centre for Invasion Biology Natural Resources and the EnvironmentCSIR

Background: Prosopis species have been introduced to many areas outside their native range to provide benefits to local communities. Several Prosopis species and their hybrids(hereafter "mesquite") have, however, become naturalised and invasive and now generate substantial costs. Management options are limited because of the complex conflicts of interest regarding benefits and costs. Management policies and strategies must take account of such conflicts, but further insights are needed on the dimensions of uses and impacts before such information can be usefully applied. Current policy in South Africa allows for the growth and use of mesquite in one province,but not in others where its control is mandatory. We report on a study to quantify the direct use and perceptions of non-timber forest products(NtFPs) from mesquite and native trees in South ***: Semi-structures household interviews were conducted with various stakeholder groups to identify what tree products are used, to ascertain amounts used as well as to gauge perceptions of natural resource use between different tree species and use over ***: the direct household use value of native trees was higher than that of mesquite, and local stakeholders attached greater value to products from native trees than from mesquite. therefore, native trees are and will still be preferentially harvested, and mesquite is unlikely to offer protection to native species by providing an alternative source of products. Mesquite pods do, however, provide valuable additional resources(fodder and medicinal products). the use of both native trees and mesquite is decreasing as the incomes of poorer households rise and as alternative energy sources become available. the benefits and reliance on mesquite are not as high as previously assumed and the impacts from mesquite invasions create large problems for local ***: this study provides further evidence that the impacts of mesquite exceed the benefi

关键词： Biological invasions Conflicts of interests Cost v