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Detecting Sorghum Plant and Head Features from Multispectral UAV Imagery

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Plant Phenomics 2021年第1期3卷 337-350页

作者： Yan Zhao Bangyou Zheng Scott CChapman Kenneth Laws barbara George-Jaeggli Graeme LHammer David RJordan Andries B.Potgieter The University of Queensland Queensland Alliance for Agriculture and Food InnovationCentre for Crop ScienceGattonQueensland 4343Australia CSIRO Agriculture and Food St.LuciaQueensland 4072Australia The University of Queensland School of Agriculture and Food SciencesSt.LuciaQueensland 4072Australia Department of Agriculture and Fisheries Agri-Science QueenslandWarwickQueensland 4370Australia

In plant breeding,unmanned aerial vehicles(UAVs)carrying multispectral cameras have demonstrated increasing utility for high-throughput phenotyping(HTP)to aid the interpretation of genotype and environment effects on morphological,biochemical,and physiological traits.A key constraint remains the reduced resolution and quality extracted from“stitched”mosaics generated from UAV missions across large areas.This can be addressed by generating high-quality reflectance data from a single nadir image per plot.In this study,a pipeline was developed to derive reflectance data from raw multispectral UAV images that preserve the original high spatial and spectral resolutions and to use these for phenotyping applications.Sequential steps involved(i)imagery calibration,(ii)spectral band alignment,(iii)backward calculation,(iv)plot segmentation,and(v)application.Each step was designed and optimised to estimate the number of plants and count sorghum heads within each breeding plot.Using a derived nadir image of each plot,the coefficients of determination were 0.90 and 0.86 for estimates of the number of sorghum plants and heads,respectively.Furthermore,the reflectance information acquired from the different spectral bands showed appreciably high discriminative ability for sorghum head colours(i.e.,red and white).Deployment of this pipeline allowed accurate segmentation of crop organs at the canopy level across many diverse field plots with minimal training needed from machine learning approaches.

关键词： breeding backward Plant

High-Throughput Phenotyping of Dynamic Canopy Traits Associated with Stay-Green in Grain Sorghum

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Plant Phenomics 2020年第1期2卷 269-278页

作者： J.D.Liedtke C.H.Hunt B.george-jaeggli K.Laws J.Watson A.B.Potgieter A.Cruickshank D.R.Jordan University of Hohenheim 70593 StuttgartGermany Agri-Science Queensland Department of Agriculture and FisheriesWarwickQLD 4370Australia Queensland Alliance for Agriculture and Food Innovation The University of QueenslandWarwickQLD 4370Australia Queensland Alliance for Agriculture and Food Innovation The University of QueenslandGatton CampusToowoomba QLD 4343Australia

Drought is a recurring phenomenon that puts crop yields at risk and threatens the livelihoods of many people around the globe.Stay-green is a drought adaption phenotype found in sorghum and other cereals.Plants expressing this phenotype show less drought-induced senescence and maintain functional green leaves for longer when water limitation occurs during grain fill,conferring benefits in both yield per se and harvestability.The physiological causes of the phenotype are postulated to be water saving through mechanisms such as reduced canopy size or access to extra water through mechanisms such as deeper roots.In sorghum breeding programs,stay-green has traditionally been assessed by comparing visual scores of leaf senescence either by identifying final leaf senescence or by estimating rate of leaf senescence.In this study,we compared measurements of canopy dynamics obtained from remote sensing on two sorghum breeding trials to stay-green values(breeding values)obtained from visual leaf senescence ratings in multienvironment breeding trials to determine which components of canopy development were most closely linked to the stay-green phenotype.Surprisingly,canopy size as estimated using preflowering canopy parameters was weakly correlated with stay-green values for leaf senescence while postflowering canopy parameters showed a much stronger association with leaf senescence.Our study suggests that factors other than canopy size have an important role in the expression of a stay-green phenotype in grain sorghum and further that the use of UAVs with multispectral sensors provides an excellent way of measuring canopy traits of hundreds of plots grown in large field trials.

关键词： breeding drought hundreds

Returning Chinese school-aged children and adolescents to physical activity in the wake of COVID-19: Actions and precautions

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Journal of Sport and Health Science 2020年第4期9卷 322-324页

作者： Peijie Chen Lijuan Mao george P.Nassis Peter Harmer barbara E.Ainsworth Fuzhong Li Shanghai University of Sport Shanghai 200438China Shanghai Municipal Education Commission Shanghai 200003China Department of Sports Science and Clinical Biomechanics University of Southern DenmarkOdense 5230Denmark Department of Exercise and Health Science Willamette UniversitySalemOR 97301USA School of Nutrition and Health Promotion Arizona State UniversityPhoenixAZ 85004USA Oregon Research Institute EugeneOR 97403USA

The Coronavirus disease-2019(COVID-19)pandemic is still spreading globally.As of April 7,2020,it has reached 184 countries and territories,infecting more than 1.4 million people worldwide with more than 82,000 deaths.1 The situation in China has improved significantly since December 31,2019.2 Owing to the unprecedented and effective quarantine measures taken across the country,Chinese health authorities reported on March 18,2020,that for the first time since the outbreak no new locally transmitted COVID-19 cases had been reported,marking a major turning point in the fight against the highly contagious coronavirus.3 Since then,the daily number of new cases in the mainland of China has dropped to double digits,with new infections primarily originating from incoming air passengers from outside China.

关键词： mainland outside turning

Coronavirus disease(COVID-19):The need to maintain regular physical activity while taking precautions

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Journal of Sport and Health Science 2020年第2期9卷 103-104页

The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7.

关键词： globally maintain travel

含高钙和维生素D的强化奶能有效提高健康的绝经后的中国女性体内的维生素D水平并减少骨吸收

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中国骨质疏松杂志 2013年第2期19卷 107-113页

作者： Marlena C Kruger PengCheng Ha Joanne M Todd barbara Kuhn-Sherlock Linda M Schollum Jiliang Ma george Qin Edith Lau 新西兰北帕默斯顿梅西大学中国北京基础研究和临床中心新西兰奥克兰恒天然品牌有限公司新西兰北帕默斯顿恒天然研究中心北京友谊医院香港卫生和医疗研究中心基础研究和临床中心

目的钙摄入水平低以及体内维生素D不足是导致亚洲女性罹患骨质疏松的危险因素。此项研究的目的是评估高钙维生素D强化牛奶(HCM)对健康的中国绝经后妇女的体内维生素D状态和骨吸收标志物进行干预的影响。方法本试验对象为55岁以上,绝经至... 详细信息

目的钙摄入水平低以及体内维生素D不足是导致亚洲女性罹患骨质疏松的危险因素。此项研究的目的是评估高钙维生素D强化牛奶(HCM)对健康的中国绝经后妇女的体内维生素D状态和骨吸收标志物进行干预的影响。方法本试验对象为55岁以上,绝经至少5年的女性。共有124名女性进行了总体健康状况和骨密度检查筛选。63名女性被随机分为对照组和试验组,试验组在12w内每日饮用两次高钙/维生素D强化奶(含900 mg钙、96 mg镁、2.4 mg锌和6.4μg维生素D)。2组分别在试验开始、试验2 w、8 w和12 w时测量血矿物质、25(OH)维生素D3和Ⅰ型胶原C端肽(CTX)水平。结果对照组女性平均年龄为63±4.6岁,高钙强化奶(HCM)组女性平均年龄为62±3.8岁。所测得的每日钙摄入量的基线值为HCM组260～482 mg,对照组为252～692 mg。12 w后HCM组的平均身体质量指数(BMI)显著降低(P<0.05)。HCM组的血25(OH)维生素D3水平显著提高(33.13～39.49 nmol/L),而对照组则维持不变(29.27～28.21 nmol/L)。HCM组的血CTX水平在0 w和2 w之间下降了25%,并保持不变直至第12w。从第2w开始HCM组和对照组相比血CTX水平就出现了显著差异(P<0.001)。结论通过饮用含高钙和维生素D的强化奶(HCM),在2至4w内能显著提高中国绝经妇女体内维生素D水平,并减少骨吸收破坏。如果长期持续地饮用含高钙和维生素D的强化奶(HCM),能减少骨吸收和骨量丢失的风险,从而减少患骨质疏松和由此引起骨折的风险。

关键词：中国绝经后的女性含钙强化奶骨标志物CTX 维生素D水平 25(OH)维生素D3 中国

Case-based audit and feedback around a decision aid improved antibiotic choice and duration for uncomplicated cystitis in primary care clinics

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Family Medicine and Community Health 2021年第3期9卷 10-18页

作者： Larissa Grigoryan Roger Zoorob george Germanos Mohamad Sidani Matthew Horsfield Fareed Khan Mohammad Zare Melanie Goebel Robert Atmar barbara Trautner Family and Community Medicine Baylor College of MedicineHoustonTexasUSA Internal Medicine Desert Regional Medical CenterPalm SpringsCaliforniaUSA Family and Community Medicine University of Texas McGovern Medical SchoolHoustonTexasUSA Section of Infectious Diseases Department of MedicineBaylor College of MedicineHoustonTexasUSA Center for Innovations in Quality Effectiveness and SafetyMichael E.DeBakey Veterans Affairs Medical Center and Department of MedicineBaylor College of MedicineMichael E DeBakey VA Medical CenterHoustonTexasUSA

Objectives The objective of our study was to evaluate the impact of a multifaceted stewardship intervention on adherence to the evidence-based practice guidelines on treatment of uncomplicated cystitis in primary care.We hypothesised that our intervention would increase guideline adherence in terms of antibiotic choice and duration of treatment.Design A preintervention and postintervention comparison with a contemporaneous control group was performed.During the first two study periods,we obtained baseline data and performed interviews exploring provider prescribing decisions for cystitis at both clinics.During the third period in the intervention clinic only,the intervention included a didactic lecture,a decision algorithm and audit and feedback.We used a difference-in differences analysis to determine the effects of our intervention on the outcome and guideline adherence to antibiotic choice and duration.Setting Two family medicine clinics(one intervention and one control)were included.Participants All female patients with uncomplicated cystitis attending the study clinics between 2016 and 2019.Results Our sample included 932 visits representing 812 unique patients with uncomplicated cystitis.The proportion of guideline-adherent antibiotic regimens increased during the intervention period(from 33.2%(95%CI 26.9 to 39.9)to 66.9%(95%CI 58.4 to 74.6)in the intervention site and from 5.3%(95%CI 2.3 to 10.1)to 17.0%(95%CI 9.9 to 26.6)in the control site).The increase in guideline adherence was greater in the intervention site compared with the control site with a difference-in differences of 22 percentage points,p=0.001.Conclusion A multifaceted intervention increased guideline adherence for antibiotic choice and duration in greater magnitude than similar trends at the control site.Future research is needed to facilitate scale-up and sustainability of case-based audit and feedback interventions in primary care.

关键词： cystitis audit representing

Rural congestive heart failure mortality among US elderly, 1999-2013: Identifying counties with promising outcomes and opportunities for implementation research

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Family Medicine and Community Health 2015年第2期3卷 27-38页

作者： Maria C.Mejia de Grubb Robert S.Levine barbara Kilbourne Baqar A.Husaini Tyler Skelton Lisa Gittner Michael A.Langston george E.Rust Department of Family and Community Medicine Baylor College of MedicineHoustonTXUSA Department of Sociology Tennessee State UniversityNashvilleTennesseeUSA Center for PreventionResearch Tennessee State University College of AgricultureNashvilleTennesseeUSA Department of Political Science Texas Tech UniversityLubbockTXUSA Department of Electrical Engineering and Computer Science University of TennesseeKnoxvilleTennesseeUSA Department of Family Medicine National Center for Primary CareMorehouse School of MedicineAtlantaGeorgiaUSA

Objective:Describe modern trends in congestive heart failure(CHF)among elderly(>65 years of age)in the United States,to identify potentially successful rural areas.Compare CHF mortality using multiple-(MCOD)versus underlying-(UCOD)cause of death data.Methods:U.S.Centers for Disease Control and Prevention mortality files(WONDER internet site).Results:Using MCOD data,overall mortality rates/100,000 population(and 95%confidence intervals)for CHF among persons>65 years of age(1999-2013)were 482.0(481.2-482.8)for large central and large fringe metropolitan(LCLF)counties,549.6(548.6-550.7)in small and medium metropolitan(SM)counties,and 652.6(650.9-654.0)in micropolitan and non-core,non-metropolitan(MNCNM)counties.Twenty positive deviance NCNM counties(collectively including 198,581 residents>65 years of age)had an overall CHF rate of 300.9(275.0-326.9)in 2013.This was significantly lower than the LCLF rate for 2013(482.0[481.2-482.8]),and rep-resented a reduction of 47%since 1999.Overall CHF occurrence as estimated with MCOD was 3.4-fold higher than that obtained with UCOD.Conclusion:These data illustrate underestimation of CHF by UCOD data and the importance of correct death certification.Rural CHF mortality rates are higher than urban rates,but some positive deviance counties demonstrate that this is not inevitable.Further research is needed to understand the relative contribution of research innovation,medical care,and public health to rural-urban disparities and the relative success of positive deviance counties.

关键词： Congestive heart failure elderly mortality rural

健康快讯:预测心脏年龄及美国各州成年人在心脏年龄上的种族差异

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上海预防医学 2017年第8期29卷 656-662页

作者： Quanhe Yang Yuna Zhong Matthew Ritchey Mark Cobain Cathleen Gillespie Robert Merritt Yuling Hong Mary G.george barbara A Bowman 宋彦(译) 洪玉玲(审校) 杨全和(审校) 蔡颖(审校) 美国疾病预防控制中心心脏病和中风预防处英国伦敦Habit Partners Community Interest公司不详

1前言心血管疾病每年在美国导致近80万人死亡,并造成大约3 200亿美元的花费。研究已经识别出若干可变心血管疾病危险因素,包括高血压、吸烟、高胆固醇、糖尿病以及超重和肥胖。心血管疾病危险因素发生率的不同对美国心血管疾病发病率和... 详细信息

1前言心血管疾病每年在美国导致近80万人死亡,并造成大约3 200亿美元的花费。研究已经识别出若干可变心血管疾病危险因素,包括高血压、吸烟、高胆固醇、糖尿病以及超重和肥胖。心血管疾病危险因素发生率的不同对美国心血管疾病发病率和死亡率在人种、社会经济和地区上出现持续差异起着重要作用。

关键词：种族差异美国成年人心血管疾病年龄心脏疾病危险因素预测

Data-driven Bayesian model-based prediction of fatigue crack nucleation in Ni-based superalloys

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npj Computational Materials 2022年第1期8卷 354-368页

作者： Maxwell Pinz george Weber Jean Charles Stinville Tresa Pollock Somnath Ghosh Civil&Systems Engineering Johns Hopkins UniversityBaltimoreMD21218USA Materials Department University of CaliforniaSanta BarbaraCA93106USA Departments of Civil&Systems Engineering Mechanical Engineeringand Materials Science&EngineeringJohns Hopkins UniversityBaltimoreMD21218USA

This paper develops a Bayesian inference-based probabilistic crack nucleation model for the Ni-based superalloy René88DT under fatigue loading.A data-driven,machine learning approach is developed,identifying underlying mechanisms driving crack nucleation.An experimental set of fatigue-loaded microstructures is characterized near crack nucleation sites using scanning electron microscopy and electron backscatter diffraction images for correlating the grain morphology and crystallography to the location of crack nucleation sites.A concurrent multiscale model,embedding experimental polycrystalline microstructural representative volume elements(RVEs)in a homogenized material,is developed for fatigue simulations.The RVE domain is modeled by a crystal plasticity finite element model.An anisotropic continuum plasticity model,obtained by homogenization of the crystal plasticity model,is used for the exterior domain.A Bayesian classification method is introduced to optimally select informative state variable predictors of crack nucleation.From this principal set of state variables,a simple scalar crack nucleation indicator is formulated.

关键词： crack fatigue superalloy