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Can a multistage approach improve individual tree mortality predictions across the complex mixed-species and managed forests of eastern North America?

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Forest Ecosystems 2023年第1期10卷 21-30页

作者： Cen Chen john kershaw jr.aaron weiskittel Elizabeth McGarrigle Center for Research on Sustainable Forests University of MaineOronoME04469USA Faculty of Forestry&Environmental Management University of New BrunswickFrederictonNBE3B 5A3Canada Nova Scotia Department of Natural Resources HalifaxNSB3J 3M8Canada

Tree mortality plays a fundamental role in the dynamics of forest ecosystems,yet it is one of the most difficult phenomena to accurately *** modeling strategies have been developed to improve individual tree mortality *** less explored strategy is the use of a multistage modeling *** improvements from this approach have remained largely *** this study,we developed a novel multistage approach and compared its performance in individual tree mortality predictions with a more conventional approach using an identical individual tree mortality model *** permanent plot data(n=9442)covering the Acadian Region of North America and over multiple decades(1965–2014)were used in this *** results indicated that the model behavior with the multistage approach better depicted the observed mortality and showed a notable improvement over the conventional *** difference between the observed and predicted numbers of dead trees using the multistage approach was much smaller when compared with the conventional *** addition,tree survival probabilities predicted by the multistage approach generally were not significantly different from the observations,whereas the conventional approach consistently underestimated mortality across species and overestimated tree survival probabilities over the large range of DBH in the *** new multistage approach also predictions of zero mortality in individual plots,a result not possible in conventional ***,the new approach was more tolerant of modeling errors because it based estimates on ranked tree mortality rather than error-prone predicted ***,this new multistage approach deserves to be considered and tested in future studies.

关键词： Tree mortality modeling Mortality disaggregation Mixed effect model Annualization Mixed forests

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An imputation/copula-based stochastic individual tree growth model for mixed species Acadian forests： a case study using the Nova Scotia permanent sample plot network

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Forest Ecosystems 2017年第4期4卷 251-263页

作者： john A. kershaw jr.aaron R. weiskittel Michael B. Lavigne Elizabeth McGarrigle University of New Brunswick FrederictonNBCanada University of Maine OroooMEUSA Atlantic Forestry Centre Natural Resources Canada.FrederiaooNBCanada Nova Scotia Natural Resources Forestry DivisionTruroNS B2N 0G9UK.

Background： A novel approach to modelling individual tree growth dynamics is proposed. The approach combines multiple imputation and copula sampling to produce a stochastic individual tree growth and yield projection system. Methods： The Nova Scotia, Canada permanent sample plot network is used as a case study to develop and test the modelling approach. Predictions from this model are compared to predictions from the Acadian variant of the Forest Vegetation Simulator, a widely used statistical individual tree growth and yield model. Results： Diameter and height growth rates were predicted with error rates consistent with those produced using statistical models. Mortality and ingrowth error rates were higher than those observed for diameter and height, but also were within the bounds produced by traditional approaches for predicting these rates. Ingrowth species composition was very poorly predicted. The model was capable of reproducing a wide range of stand dynamic trajectories and in some cases reproduced trajectories that the statistical model was incapable of reproducing. Conclusions： The model has potential to be used as a benchmarking tool for evaluating statistical and process models and may provide a mechanism to separate signal from noise and improve our ability to analyze and learn from large regional datasets that often have underlying flaws in sample design.

关键词： Nearest neighbor imputation Copula sampling Individual tree growth model Mortality Ingrowth Mixed species stand development Acadian forests Nova Scotia

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Molar ratio induced crystal transformation from coordination complex to coordination polymers

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Chinese Chemical Letters 2024年第4期35卷 539-543页

作者： Peng Meng Qian-Cheng Luo Aidan Brock Xiaodong Wang Mahboobeh Shahbazi aaron Micallef john McMurtrie Dongchen Qi Yan-Zhen Zheng Jingsan Xu School of Chemistry and Physics&Centre for Materials Science Queensland University of TechnologyBrisbaneQLD 4000Australia Frontier Institute of Science and Technology Xi'an Jiaotong UniversityXi'an 710054China Central Analytical Research Facility Institute for Future EnvironmentsQueensland University of TechnologyBrisbaneQLD 4000Australia

Coordination complex of a copper cyanurate(Cu(Ⅱ)-CA) was transformed into coordination polymers upon the stimulus of extra Cu(Ⅱ) through “directed Ostwald ripening”. By increasing the molar ratio of Cu(Ⅱ) to CA, we obtained two coordination polymers with selective coordination sites: Cu(Ⅱ)-κ N(HCA)κ NCu(Ⅱ) and Cu(Ⅱ)-κ N(HCA)κ O-Cu(Ⅱ), which display disparate magnetic interactions.

关键词： Molar ratio dependent crystal transformation Copper cyanurate Ostwald ripening Molecular magnetism One-dimensional chain

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Cerebral venous sinus thrombosis:changing trends in the incidence,age and gender(findings from the CMC Vellore CVT registry)

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Stroke & Vascular Neurology 2024年第3期9卷 252-257页

作者： Angel Miraclin T john Davis Prasad George Abraham Ninan Mahasampath Gowri Deepti Bal Atif Iqbal Ahmed Shaikh Rohit N Benjamin Appaswamy Thirumal Prabhakar Ajith Sivadasan Vivek Mathew Sanjith aaron Department of Neurological Sciences Christian Medical CollegeVelloreTamil NaduIndia Department of Biostatistics Christian Medical CollegeVelloreTamil NaduIndia

Background Multiple cerebral venous sinus thrombosis(CVT)registries from various geographical regions indicate that female gender,the use of contraceptive pills,pregnancy and puerperium are important risk *** this study,we report the changes in the epidemiology of patients with CVT managed over the past 26 *** The CMC Vellore CVT registry is a prospectively maintained database at the Christian Medical College,Vellore since January *** software was used to analyse the data and assess the changes in the incidence,age and gender distribution over the previous 26 *** Among 1701 patients treated during the study period,908(53%)were women and 793(47%)were *** mean incidence of CVT was 49 per 100000 admissions before 2010,which increased to 96 per 100000 after *** gender had a higher odds of developing CVT OR–2.07(CI 1.68 to 2.55,p<0.001).This could be attributed to the declining incidence of postpartum CVT after 2010 compared with the decade before 2010(50%vs 20%).The mean age at presentation had increased from 24.5 to 33.2 years in the last *** There was a clear change in the gender pattern from being a condition with female preponderance,to one where equal or more men are being *** incidence of postpartum CVT cases could be the driving *** increase in the overall incidence of CVT cases was noted,probably due to a higher index of clinical suspicion and better diagnostic imaging modalities.

关键词： CVT driving maintained

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Development and evaluation of an individual tree growth and yield model for the mixed species forest of the Adirondacks Region of New York, USA

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Forest Ecosystems 2017年第1期4卷 66-82页

作者： aaron weiskittel Christian Kuehne john Paul McTague Mike Oppenheimer University of Maine School of Forest Resources Orono ME 04469 USA. Rayonier Forest Research Center Yulee FL 32041 USA Rayonier Foresl Resources Fernandina Beach FL 32035 USA. University of Maine 5755 I Nutting Hall Orono ME 04469-5755 USA.

Background： Growth and yield models are important tools for forest planning. Due to its geographic location, topology, and history of management, the forests of the Adirondacks Region of New York are unique and complex. However, only a relatively limited number of growth and yield models have been developed and/or can be reasonably extended to this region currently. Methods： in this analysis, 571 long-term continuous forest inventory plots with a total of 10 - 52 years of measurement data from four experimental forests maintained by the State University of New York College of Environmental Science and Forestry and one nonindustrial private forest were used to develop an individual tree growth model for the primary hardwood and softwood species in the region. Species-specific annualized static and dynamic equations were developed using the available data and the system was evaluated for long-term behavior. Results： Equivalence tests indicated that the Northeast Variant of the Forest Vegetation Simulator （FVS-NE） was biased in its estimation of tree total and bole height, diameter and height increment, and mortality for most species examined. In contrast, the developed static and annualized dynamic, species-specific equations performed quite well given the underlying variability in the data. Long-term model projections were consistent with the data and suggest a relatively robust system for prediction. Conclusions： Overall, the developed growth model showed reasonable behavior and is a significant improvement over existing models for the region. The model also highlighted the complexities of forest dynamics in the region and should help improve forest planning efforts there.

关键词： Individual tree growth model Mixed species Forest vegetation simulator

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2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities

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Journal of Sport and Health Science 2024年第1期13卷 6-12页

作者： Stephen D.Herrmann Erik A.Willis Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht john M.Schuna jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. Jacobs jr. Kansas Center for Metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of Exercise and Health Shanghai University of SportShanghai 200438China Exercise Science Department Syracuse UniversitySyracuseNY 13244USA Clinical Sciences Division Pennington Biomedical Research CenterBaton RougeLA 70808USA School of Exercise and Sport Science Oregon State UniversityCorvallisOR 97331USA College of Health and Human Services University of North Carolina at CharlotteCharlotteNC 28223USA Gramercy Research Group KnightdaleNC 27545USA Division of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across *** original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health ***:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 *** a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since *** replaced estimated METs with measured values when ***:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 *** added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older *** added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major ***:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health *** new website with the complete lists of PAs and supporting resources is available at https://***.

关键词： Adults Energy expenditure Exercise MET Physical Activities

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Alternative expressions for stand diameter in complex forests

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Forest Ecosystems 2023年第3期10卷 328-336页

作者： Mark J.Ducey john A.kershaw jr. Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA Faculty of Forestry and Environmental Management University of New BrunswickFrederictonNBCanada

Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of *** such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and economic ***,quadratic mean diameter can be heavily influenced by the presence or absence of large numbers of small stems in lower canopy strata,and it is also sensitive to left-truncation of the diameter distribution,making its interpretation across inventories with different protocols ***,we examine three alternative expressions of stand diameter:the arithmetic and quadratic mean diameter of the thickest 100 trees per hectare,and the basal area-weighted mean *** data from the United States Forest Inventory and Analysis program for New York and New England,these alternative expressions showed closer correlation with multiple stand structural variables than did quadratic mean diameter,including merchantable cubic and board foot volume per hectare,aboveground live tree carbon per hectare,and total number of live and dead standing trees greater than 40 cm diameter at breast height per hectare(previously proposed as an index of old-growth structure).Arithmetic and quadratic mean diameter of the thickest 100 trees per hectare showed nearly identical performance,and the strongest correlations across the *** develop closed-form expressions for these variables when the diameter distribution is a Weibull,and illustrate their behavior relative to quadratic mean diameter for that *** the reasons for prevalence of quadratic mean diameter as an indicator remain valid,we suggest that these alternative measures should be more widely reported and analyzed to give a more informative depiction of stand structure and development in complex forests.

关键词： Forest structure Diameter at breast height Weibull distribution

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Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

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Journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： Erik A.Willis Stephen D.Herrmann Mary Hastert Chelsea L.Kracht Tiago V.Barreira john M.Schuna jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy J.Brown Barbara E.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA Exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of Exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of Exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older *** developed a website to present the OA Compendium MET_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice.

关键词： Energy expenditure Exercise MET Older adults

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Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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Journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher Michael J.LaMonte Andrea Z.LaCroix Eleanor M.Simonsick Steven P.Hooker Humberto Parada jr. john Bellettiere Arun Kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego Moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(ML),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:Measured VO_(2max)is a strong predictor of *** ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology Mortality

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The delivery of N-myc downstream-regulated gene 2(NDRG2)self-amplifying mRNA via modified lipid nanoparticles as a potential treatment for drug-resistant and metastatic cancers

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Medical Review 2024年第3期4卷 235-238页

作者： Sandra E.Reznik Amit K.Tiwari Vivek Chavda Charles R.Ashby jr. Department of Pharmaceutical Sciences College of Pharmacy and Health SciencesSt.John’s UniversityQueensUSA Departments of Pathology and Obstetrics and Gynecology and Women’s Health Montefiore Medical Center/Albert Einstein College of MedicineBronxUSA Department of Pharmaceutical Sciences College of Pharmacy University of Arkansas for Medical Sciences Little RockUSA Department of Pharmaceutics and Pharmaceutical Technology L.M.College of Pharmacy AhmedabadIndia Department of Pharmaceutical Sciences College of Pharmacy and Health SciencesSt.John’s UniversityQueensNY 11439USA

The protein,N-myc downstream-regulated gene 2(NDRG2),a tumor suppressor,is significantly decreased or absent in many types of *** is a significant negative correlation between the levels of NDRG2 and the development and progression of cancer tumor recurrence and tumor invasion,in different *** contrast,the in vitro and in vivo overexpression of the NDRG2 protein decreases the proliferation,growth,adhesion and migration of many types of cancer *** in vitro overexpression of NDRG2 increases the efficacy of certain anticancer drugs in specific types of cancer *** hypothesize that the delivery of the mRNA of the NDRG2 protein,encapsulated by lipid nanoparticles,could represent a potential treatment of metastatic and drug-resistant *** would be accomplished using a self-amplifying mRNA that encodes the NDRG2 protein and an RNA-dependent-RNA polymerase,obtained from an in vitrotranscribed(IVT)*** IVT mRNA would be encapsulated in a lipid *** efficacy of the nanoformulation would be determined in cultured cancer cells and if the results are positive,nude mice transplanted with either drug-resistant or metastatic drug-resistant cancer cells,would be treated with the nanoformulation and monitored for efficacy and adverse *** the appropriate preclinical studies indicate this formulation is efficacious and safe,it is possible it could be evaluated in clinical trials.

关键词： N-myc downstream-regulated gene 2(NDRG2) cancer self-amplifying mRNA nanoparticle

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