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Cold adaptation does not alter ATP homeostasis during cold exposure in Drosophila melanogaster

Integrative Zoology 2018年第4期13卷 471-481页

作者： Caroline m.WILLIAmS James R.ROCCA Arthur S.EDISON David B.ALLISON Theodore J.morgan Daniel A.HAHN Department of Integrative Biology University of CaliforniaBerkeleyCaliforniaUSA Departments of Entomology and Nematology University of FloridaGainesvilleFloridaUSA Biochemistry University of FloridaGainesvilleFloridaUSA Advanced magnetic Resonance Imaging and Spectroscopy Facility McKnight Brain InstituteUniversity of FloridaGainesvilleFloridaUSA Departments of Genetics and Biochemistry Complex Carbohydrate Research CenterUniversity of GeorgiaAthensGeorgiaUSA Department of Epidemiology and Biostatistics School of Public HealthIndiana University BloomingtonBloomingtonIndianaUSA Division of Biology Kansas State UniversityManhattanKansasUSA

In insects and other ectotherms,cold temperatures cause a coma resulting from loss of neuromuscular function,during which ionic and metabolic homeostasis are progressively *** adaptation improves homeostasis during cold exposure,but the ultimate targets of selection are still an open *** acclimation and adaptation remodels mitochondrial metabolism in insects,suggesting that aerobic energy production during cold exposure could be a target of ***,we test the hypothesis that cold adaptation improves the ability to maintain rates of aerobic energy production during cold exposure by using^(31)P NmR on live *** lines of Drosophila melanogaster artificially selected for fast and slow recovery from a cold coma,we show that cold exposure does not lower ATP levels and that cold adaptation does not alter aerobic ATP production during cold ***-hardy and cold-susceptible lines both experienced a brief transition to anaerobic metabolism during cooling,but this was rapidly reversed during cold exposure,suggesting that oxidative phosphorylation was sufficient to meet energy demands below the critical thermal minimum,even in cold-susceptible *** thus reject the hypothesis that performance under mild low temperatures is set by aerobic ATP supply limitations in ***,excluding oxygen and capacity limitation as a weak link in energy *** work suggests that the modulations to mitochondrial metabolism resulting from cold acclimation or adaptation may arise from selection on a biosynthetic product(s)of those pathways rather than selection on ATP supply during cold exposure.

关键词： chill coma energetics insect oxygen limitation thermal tolerance

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Assessment of left-ventricular diastolic function in pediatric intensive-care patients:a review of parameters and indications compared with those for adults

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World Journal of Pediatrics 2021年第1期17卷 21-30页

作者： morgan Recher Astrid Botte Jerome Soquet Jean-Benoit Baudelet François Godart Stephane Leteurtre ULR 2694-mETRICS:évaluation des Technologies de santéet des Pratiques médicales Univ.LilleCHU Lille59000 LilleFrance Réanimation et Surveillance Continue Pédiatriques Hopital Jeanne de FlandreCHU de Lille59037 Lille CedexFrance Pediatric and Neonatal Intensive Care Unit CHU Bordeaux33076 BordeauxFrance Cardiac Surgery Unit CHU Lille59000 LilleFrance Congenital and Pediatric Cardiology Unit CHU Lille59000 LilleFrance

Background The incidence of diastolic heart failure has increased over *** evaluation of left-ventricular diastolic func-tion is complex,ongoing,and remains poorly performed in pediatric intensive-care *** study aimed to review the literature and to provide an update on the evaluation of left-ventricular diastolic function in adults and children in intensive *** sources We searched data from Pubmed/***-two studies were *** pragmatic questions were identified:(1)What is the physiopathology of diastolic dysfunction?(2)Which tools are required to evaluate diastolic func-tion?(3)What are the echocardiographic criteria needed to evaluate diastolic function?(4)When should diastolic function be evaluated in pediatric intensive care?Results Early diastole allows characterization of relaxation,whereas compliance assessments and filling pressures are evalu-ated during late *** evolution of diastolic function differs between adults and *** in adults,decreased compliance occurs at the same time as delayed relaxation in *** function can be evaluated by Doppler *** echocardiographic criteria for ventricular relaxation include the E wave,E/A wave ratio,and isovolumic relaxation *** compliance can be assessed by the E/e'wave ratio,atrial volume,and Ap wave duration during pulmonary vein *** adult intensive-care patients,the E/e'ratio can be used as an index of tolerance for volume expan-sion in septic patients and to adjust the inotropic *** Clinical studies would allow some of these parameters to be validated for use in children in intensive care.

关键词： Diastole Echocardiography Heart failure Intensive-care unit Pediatric

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Spatial patterns of plant diversity and communities in Alpine ecosystems of the Hengduan mountains, northwest Yunnan, China

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Journal of Plant Ecology 2008年第2期1卷 117-136页

作者： ruth Sherman Renee mullen Li Haomin Fang Zhendong Wang Yi Department of Natural Resources Cornell UniversityIthacaNY 14853USA The Nature Conservancy BoiseID 83702USA The Nature Conservancy China ProgramKunmingYunnan 650034People’s Republic of China Shangri-la Alpine Botanical Garden ZhongdianYunnan674400People’s Republic of China Biology Department Yunnan UniversityKunmingYunnan650091People’s Republic of China

Aims Conduct a quantitative,but rapid,regional-level assessment of the alpine flora across northwest Yunnan(NWY)to provide a broadbased understanding of local and regional patterns of the composition,diversity and health of alpine ecosystems across *** A stratified random sampling design was employed to select sites across the different mountain ranges of *** was sampled by stratifying each site by the three major alpine vegetation community types:meadow,dwarf shrub and *** 50-m transects were randomly located within each community type at each sampling site with 101-m^(2) subplots systematically placed along each *** variables were recorded at each *** analyses were used to classify the major plant community assemblages and link community patterns to environmental and habitat *** Findings Forb species richness varied from 19 to 105 species per site(21 sites total)with an average of 59 species per site(60 m^(2) sampled per site).most species were patchily distributed with narrow distributions and/or small population sizes;over half the species occurred at only one or two *** species assemblages were identified in the meadow vegetation that was strongly aggregated by geographic location suggesting the presence of distinct phytogeographic zones of the meadow alpine *** and geographic location were the dominant environmental gradients underlying the variations in species ***’s coefficient of similarity averaged only 10%among sites indicating there was little similarity in the alpine flora across the *** alpine vegetation is highly heterogeneous across the complex landscape of the Hengduan mountains of *** strategies need to take into account the large geographic differences in the flora to maximize protection of biodiversity.

关键词： biodiversity hotspot community ecology multivariate analysis Yunnan Great Rivers Project(YGRP) World Heritage Site

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Transepithelial leak in Barrett's esophagus patients: The role of proton pump inhibitors

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World Journal of Gastroenterology 2012年第22期18卷 2793-2797页

作者： Christopher Farrell melissa morgan Owen Tully Kevin Wolov Keith Kearney Benjamin Ngo Giancarlo mercogliano James J Thornton mary Carmen Valenzano James m mullin Division of Gastroenterology Lankenau Hospital Wynnewood PA 19096 United States Lankenau Institute for medical Research Wynnewood PA 19096 United States

AIm： To determine if the observed paracellular sucrose leak in Barrett＇s esophagus patients is due to their pro- ton pump inhibitor （PPI） use. mETHODS： The in vivo sucrose permeability test was administered to healthy controls, to Barrett＇s patients and to non-Barrett＇s patients on continuous PPI thera- py. Degree of leak was tested for correlation with pres- ence of Barrett＇s, use of PPIs, and length of Barrett＇s segment and duration of PPI use. RESULTS： Barrett＇s patients manifested a near 3-fold greater, upper gastrointestinal sucrose leak than healthy controls. A decrease of sucrose leak was ob- served in Barrett＇s patients who ceased PPI use for 7 *** initial introduction of PPI use （in a PPI-na＇ive population） results in dramatic increase in sucrose leak, long-term, continuous PPI use manifested a slow spon- taneous decline in leak. The sucrose leak observed in Barrett＇s patients showed no correlation to the amount of Barrett＇s tissue present in the esophagus. CONCLUSION： Although future research is needed to determine the degree of paracellular leak in actual Barrett＇s mucosa, the relatively high degree of leak ob- served with in vivo sucrose permeability measurement of Barrett＇s patients reflects their PPI use and not their Barrett＇s tissue perse.

关键词： Barrett's esophagus Sucrose Tight junc-tion Paracellular, Omeprazole Proton pump inhibitor Transepithelial

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Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

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Journal of Environmental Sciences 2013年第9期25卷 1847-1857页

作者： Ciaran Lewis Rashad Rafique Nelius Foley Paul Leahy Gerard morgan John Albertson Sandeep Kumar Gerard Kiely Department of Civil and Environmental Engineering University College Cork Department of microbiology and Plant Biology University of Oklahoma Environmental Research Institute University College Cork Aquatic Services Unit Environmental Research Institute University College Cork Department of Civil and Environmental Engineering Duke University Department of Plant Science South Dakota State University

We carried out a one year （2002） study of phosphorus （P） loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between march and September and animal slurry was applied over the twelve months. The annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha, respectively. The annual total phosphorus （TP） export in stream-flow was 2.61, 2.48 and 1.61 kg P/ha for the 17, 211 and 1524 ha catchments, respectively, compared with a maximum permissible （by regulation） annual export of ca. 0.35 kg P/ha. The export rate （ratio of P export to P in land applications） was 9.6% and 6.6% from the 17 and 211 ha catchments, respectively. On average, 70% of stream flow and 85% of the P export occurred during the five wet months （October to February） indicating that when precipitation is much greater than evaporation, the hydrological conditions are most favourable for P export. However the soil quality and land use history may vary the results. Particulate P made up 22%, 43% and 37% of the TP export at the 17, 211 and 1524 ha catchment areas, respectively. As the chemical fertilizer was spread during the grass growth months （march to September）, it has less immediate impact on stream water quality than the slurry applications. We also show that as the catchment scale increases, the P concentrations and P export decrease, confirming dilution due to increasing rural catchment size. In the longer term, the excess P from fertilizer maintains high soil P levels, an antecedent condition favourable to P loss from soil to water. This study confirms the significant negative water quality impact of excess P applications, particularly liquid animal slurry applications in wet winter months. The findings suggest that restricted P application in w

关键词： phosphorus fertilizer slurry exports grassland land management water quality eutrophication

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Upper range limit establishment after wildfire of an obligateseeding montane forest tree fails to keep pace with 20th century warming

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Journal of Plant Ecology 2018年第2期11卷 200-207页

作者： John W.morgan James D.Vincent James S.Camac Research Centre for Applied Alpine Ecology Department of EcologyEnvironment and EvolutionLa Trobe UniversityKingsbury DriveBundooraVIC 3086Australia Department of Biological Sciences Macquarie UniversityBalaclava RoadNorth RydeNew South Wales 2109Australia

Aims How species respond to climate change at local scales will depend on how edaphic and biological characteristics interact with species physiological limits and traits such as *** seeders,those species that depend on fire for recruitment,have few and epi-sodic opportunities to track a changing climate *** such cases,long-distance seed dispersal will be necessary to take advan-tage of rare recruitment *** examine recruitment patterns and seedling growth below,at and above the timberline of an obligate-seeding Australian montane forest tree(Eucalyptus delegatensis)after stand-replacing fire,and place these changes in the context of regional *** We use two methods to detect whether *** can estab-lish and persist above the timberline after stand-replacing wildfire in montane forests in south-east ***,we examine estab-lishment patterns by using belt transects at six sites to quantify how changes in post-fire recruit density with increasing distance above the timberline seven years ***,to determine whether dispersal or physiological constraints determine post-fire establish-ment patterns,we transplanted seedlings and saplings into bare ground above(100 m elevation),at,and below(50 m elevation)timberline 18-months after *** monitored seedling growth and survival for one growing *** Findings There was minimal upslope migration of the species after fire with most saplings observed near seed-bearing timberline trees,with only occasional outpost *** seedlings and saplings sur-vived equally well across one growing season when planted above existing timberlines,relative to saplings at or below the *** and sapling growth rates also did not differ across these location,although seedlings grew at much faster rates than *** findings suggest that upslope growing season conditions are unlikely to limit initial range expansion of trees aft

关键词： climate change dispersal limitation growth rates regeneration niche timberline

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Two-way communication: Volatile emission and uptake occur through the same barriers

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molecular Plant 2023年第1期16卷 1-3页

作者： Joshua R.Widhalm meng-Ling Shih John A.morgan Natalia Dudareva Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN 47907USA Center for Plant Biology Purdue UniversityWest LafayetteIN 47907USA avidson School of Chemical Engineering Purdue UniversityWest LafayetteIN 47907USA Department of Biochemistry Purdue UniversityWest LafayetteIN 47907USA

Volatile organic compounds(VOCs)are released from aboveground organs into the atmosphere and/or from roots into the soil,allowing plants to communicate and interact with their environment,including with each ***-plant communication via VOCs includes intra-and inter-species signaling as well as within-plant *** some recipient tissues,for example,VOC perception encompasses storing the modified VOC for direct defense against herbivores(Sugimoto et al.,2014)or increasing tolerance to abiotic stresses(Zhao et al.,2020).In addition,or alternatively,perceived VOCs may initiate signaling cascades that prime plant defenses(Brosset and Blande,2022).In all cases,plant VOCs are first released into the environment before being taken up and perceived by the same or neighboring *** significant progress has been made over the last several years to elucidate how VOCs are released from plant cells,these studies have also revealed new questions about how communicated VOCs are imported across cellular *** reviews(Loreto and D’Auria,2022;Wang and Erb,2022)and a special issue(Vlot and Rosenkranz,2022)have proposed mechanisms for VOC perception and *** this Opinion piece,we shed light on the gaps in knowledge about VOC import and offer perspectives for future research aiming at understanding the molecular mechanisms underlying VOC-mediated communication in plants.

关键词： communicate soil barriers

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Arsenic speciation in freshwater fish:challenges and research needs

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Food Quality and Safety 2023年第3期7卷 383-407页

作者： Karen S.Hoy Tetiana Davydiuk Xiaojian Chen Chester Lau Jordan R.m.Schofield Xiufen Lu Jennifer A.Graydon ruth mitchell megan Reichert X.Chris Le Department of Chemistry University of AlbertaEdmontonAlbertaCanada Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlbertaCanada Alberta Health Health Protection BranchEdmontonAlbertaCanada

Food and water are the main sources of human exposure to *** is important to determine arsenic species in food because the toxicities of arsenic vary greatly with its chemical *** research has focused on high concentrations of arsenic species in marine *** concentrations of arsenic species in freshwater fish are much lower,and their determination presents analytical *** this review,we summarize the current state of knowledge on arsenic speciation in freshwater fish and discuss challenges and research *** samples are typically homogenized,and arsenic species are extracted using water/methanol with the assistance of sonication and enzyme *** species in the extracts are commonly separated using high-performance liquid chromatography(HPLC)and detected using inductively coupled plasma mass spectrometry(ICPmS).Electrospray ionization tandem mass spectrometry,used in combination with HPLC and ICPmS,provides complementary information for the identification and characterization of arsenic *** methods and perspectives discussed in this review,covering sample preparation,chromatography separation,and mass spectrometry detection,are directed to arsenic speciation in freshwater fish and applicable to studies of other food *** progress made in arsenic speciation analysis,a large fraction of the total arsenic in freshwater fish remains *** is challenging to identify and quantify arsenic species present in complex sample matrices at very low *** research is needed to improve the extraction efficiency,chromatographic resolution,detection sensitivity,and characterization capability.

关键词： Arsenic species environment food consumption freshwater fish human exposure identification of unknowns liquid chromatography mass spectrometry

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A model to Estimate the Impact of Thresholds and Caps on Coverage Levels in Community-Based Health Insurance Schemes in Low-Income Countries

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Health 2014年第9期6卷 822-835页

作者： Erika Binnendijk ruth Koren David m. Dror Felsenstein medical Research Center Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel Institute of Health Policy and management Erasmus University Rotterdam Rotterdam The Netherlands micro Insurance Academy New Delhi India

Background: Community-based health insurance (CBHI) schemes are increasingly implemented in low-income settings. These schemes limit the coverage they offer both by the types of care considered, and by applying thresholds and/or caps to costs reimbursed. The consequences of these thresholds and/or caps on insurance coverage have hitherto been usually ignored, for lack of data on the distributions of healthcare costs or understanding of their impact on effective coverage levels. This article describes a theoretical model to obtain the distributions even without data collection in the field, and demonstrates the quantitative impact of thresholds and/or caps on claim reimbursements. methods: This model applies to applications on healthcare expenditures in low-income settings, following research methods examined in the Western world. We looked at hospitalizations and tests;we compared the simulated distributions to empirical data obtained through 11 household surveys conducted between 2008 and 2010 in rural locations (9 in India and 2 in Nepal). Results: We found that the shape of the distributions was very similar in all locations for both benefits, and could be represented by a model based on a lognormal distribution. The agreement between theoretical and empirical results was satisfactory (mostly within 10% difference). Conclusions: The model makes it possible to simulate the expected performance of the CBHI (represented by the percentage of costs or bills covered). The aim is to match costs with local levels of willingness-to-pay for health insurance. This model makes it possible to determine at the stage of package-design the optimal levels of thresholds and/or caps for each benefit-type included.

关键词： Distributions Healthcare Costs Community-Based Health Insurance micro Health Insurance Thresholds Caps

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Groundwater Recharge Through Infiltration Process: A Case Study of Umudike, Southeastern Nigeria

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Journal of Water Resource and Protection 2011年第5期3卷 295-299页

作者： m. U. Igboekwe Adindu ruth 不详

Although water is a renewable resource for sustaining life and environment, excessive pumping of groundwater results in the ground water table being depleted. The major natural source of groundwater recharge is rainfall. In Umudike just like many other areas, the rate of natural recharge is lower than pumping rate. This is due to increasing economic and agricultural activities and also urbanization. Over exploitation of groundwater is a threat to the water quality and table and creates hydrological imbalance. This imbalance includes degradation in hydrological and hydro-chemical characteristics of the aquifer. Artificial recharge of water table aquifers becomes necessary to improve the hydrodynamic conditions of groundwater. A drop in piezometric level can be remedied by artificial recharge of groundwater through infiltration process using water from dams, lakes, rivers, runoff and sewage effluent. Results of water table survey conducted at Umudike show that it peaks at 85m (above sea level) before recharge and 95m after recharge. The recharge of groundwater is basically through rainfall and river water.

关键词： Artificial Recharge Umudike Infiltration Water Table

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