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Drought events influence nutrient canopy exchanges and green leaf partitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso P.De Donato m.-P.Turpault INRAE BEFF-54000NancyFrance UmR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events expected in the coming decades in Western Europe may disturb forest biogeochemical cycles and create nutrient deficiencies in *** possible origin of nutrient deficiency is the disturbance of the partitioning of the green leaf pool during the leaf senescence period between resorption,foliar leaching and senesced ***,the effects of drought events on this partitioning and the consequences for the maintenance of tree nutrition are poorly *** experiment in a beech forest in meuse(France)was conducted to assess the effect of drought events on nutrient canopy exchanges and on the partitioning of the green leaf pool during the leaf senescence *** aim was to identify potential nutritional consequences of droughts for *** nutrient dynamics,including resorption,chemistry of green and senesced leaves,foliar absorption and leaching in mature beech stands from 2012 to 2019 allowed us to compare the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the potassium(K)partitioning to resorption(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity expected for the coming decades,there will be a risk of potassium deficiency in trees,as already observed in a rainfall exclusion experiment on the same study *** foliar leaching and higher parititioning to the senesced leaves for K and phosphorus(P)were also *** addition,a slight increase in nitrogen(N)resorption efficiency occurred during dry years which is more likely to improve tree *** calcium(Ca)negative resorption decreased,with no apparent consequence in our study *** results show that nutrient exchanges in the canopy and the partitioning of the green leaf

关键词： Natural drought Beech forest Canopy Resorption Foliar leaching Senesced leaves Nutrition

Short-term effects of obestatin on hexose uptake and triacylglycerol breakdown in human subcutaneous adipocytes

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World Journal of Diabetes 2018年第1期9卷 25-32页

作者： Christian Carpéné Francisco les David Estève Jean Galitzky Institut des maladies métaboliques et Cardiovasculaires Institut National de la Santé et de la Recherche Médicale Université Paul Sabatier Department of Pharmacy Faculty of Health Sciences Universidad San Jorge

AIm To study complete dose-dependent effects of obestatin on lipolytic and glucose transport activities in human adipocyte preparations highly responsive to *** Adipocytes were prepared by liberase digestion from subcutaneous abdominal adipose tissue obtained from overweight subjects undergoing plastic surgery. The index of lipolytic activity was the glycerol released in the incubation medium, while glucose transport was assessed by [~3H]-2-deoxyglucose uptake *** When tested from 0.1 nmol/L to 1 μmol/L, obestatin did not stimulate glycerol release; it did not inhibit the lipolytic effect of isoprenaline and did not alter the insulin antilipolytic effect. Obestatin hardly activated glucose transport at 1 μmol/L only. moreover, the obestatin stimulation effect was clearly lower than the threefold increase induced by insulin 100 nmol/*** Low doses of obestatin cannot directly influence lipolysis and glucose uptake in human fat cells.

关键词： Insulin Lipolysis Adipokines Glucose uptake Obestatin Human adipocytes

Hyperglycemia and reduced adiposity of streptozotocin-induced diabetic mice are not alleviated by oral benzylamine supplementation

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World Journal of Diabetes 2022年第9期13卷 752-764页

作者： Christian Carpéné Kristiyan Stiliyanov Atanasov Francisco les Josep mercader Barcelo Institut des maladies métaboliques et Cardiovasculaires INSERM UMR 1297Toulouse 31432France molecular Biology and One Health research group Department of Fundamental Biology and Health SciencesUniversity of the Balearic IslandsPalma 07122Spain Department of Pharmacy Faculty of Health SciencesUniversidad San JorgeVillanueva de GállegoZaragoza 50830Spain

BACKGROUND Benzylamine(Bza)oral administration delays the onset of hyperglycemia in insulin-resistant db-/-mice;a genetic model of obesity and type 2 *** To extend the antihyperglycemic properties of oral benzylamine to a model of insulin-deficient type 1 *** male Swiss mice were rendered diabetic by streptozotocin treatment(STZ)and divided in two groups:one received 0.5%Bza as drinking solution for 24 d(STZ Bza-drinking)while the other was drinking water ad *** groups were constituted in age-matched,nondiabetic *** intake,liquid intake,body weight gain and nonfasting blood glucose levels were followed during *** the end of treatment,fasted glycemia,liver and white adipose tissue(WAT)mass were measured,while glucose uptake assays were performed in *** STZ diabetic mice presented typical features of insulin-deficient diabetes:reduced body mass and increased blood glucose *** altered parameters were not normalized in the Bza-drinking group in spite of restored food and water *** consumption could not reverse the severe fat depot atrophy of STZ diabetic *** the nondiabetic mice,no difference was found between control and Bza-drinking mice for any *** isolated adipocytes,hexose uptake was partially activated by 0.1 mmol/L Bza in a manner that was obliterated in vitro by the amine oxidase inhibitor phenelzine and that remained unchanged after Bza *** of 0.1 mmol/L Bza in WAT was lower in STZ diabetic than in normoglycemic *** Bza supplementation could not normalize the altered glucose handling of STZ diabetic mice with severe WAT ***,its antidiabetic potential in obese and diabetic rodents does not apply to lipoatrophic type 1 diabetic mice.

关键词： Diabetes Adipocytes Amine oxidases Insulin-like agents Glucose transport Polydipsia

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采用随机试验确定何时监测新治疗方法的反应

英国医学杂志中文版 2008年第3期11卷 168-173页

作者： Katy J L Bell les irwig Jonathan C Craig Petra macaskill 汪海波(译) Screening and Test Evaluation Program School of Public Health Edward Ford Building (A27) The University of Sydney NSW 2006 不详

监测治疗的初始反应在患者的临床管理中总是有帮助的吗？ Katy Bell和他的同事们建立了一个理论框架。

关键词：治疗方法监测治疗反应随机试验临床管理指标监测慢性病

Analysis of Impervious Surface Area, and the Impacts on Soil-Based Agriculture and the Hydrologic Cycle: A Case Study in the Agricultural Land Reserve in metro Vancouver, British Columbia, Canada

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Agricultural Sciences 2017年第8期8卷 837-856页

作者： Ashley Rose Julie E. Wilson les m. Lavkulich master of Land and Water Systems Faculty of Land and Food Systems The University of British Columbia Vancouver Canada

The province of British Columbia, Canada, has established an Agricultural Land Reserve (ALR) to protect the most suitable soil landscapes for agriculture. Increases in population and urbanization have resulted in development challenges on ALR lands. The metro Vancouver area is the most productive agricultural area in British Columbia as well as the most rapidly growing urban region. The increase in impervious areas has decreased the amount of arable land for soil-based agriculture and altered the hydrological cycle. Analysis using a combination of aerial imagery and GIS found that impervious areas comprise about 10 percent of the ALR within metro Vancouver. Farm residences and greenhouses have the largest effect on reducing the soil surface for water infiltration. This decrease in area has negatively influenced the ecosystem heath of the region, as well as, decreasing the amount of agricultural land for soil based agriculture and both surface and groundwater dynamics.

关键词： Agricultural Land Reserve Impervious Surfaces Watershed Health Stormwater Runoff Hydrology

Integration of Agriculture and Wildlife Ecosystem Services: A Case Study of Westham Island, British Columbia, Canada

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Agricultural Sciences 2017年第5期8卷 409-425页

作者： Yuan Zhang Julie E. Wilson les m. Lavkulich master of Land and Water Systems Faculty of Land and Food Systems The University of British Columbia Vancouver Canada

There is concern regarding the loss of ecosystem goods and services as a result of land use changes such as the expansion and intensification of agricultural activities. Assessments of these interactions require innovative analyses that combine qualitative and quantitative economic analyses. The millennium Ecosystem Assessment framework was applied to a peri-urban region in British Columbia, Canada to assess the effects of the integration of agricultural programs and the maintenance of waterfowl habitat located on the Pacific Flyway. The Delta Farmland & Wildlife Trust, a non-governmental organization, has implemented several activities to enhance ecosystem goods and services by cooperative programs among the agricultural community and wildlife interests. The successful collaborative framework has resulted in enhanced soil quality, increased biodiversity, and the maintenance of valuable agriculture and waterfowl habitat.

关键词： Ecosystem Services Agriculture Land Use Change Wildlife Habitat

Effects of Aggregate Extraction on Water Storage in the Pepin Creek Watershed, British Columbia, Canada

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Natural Resources 2017年第7期8卷 461-477页

作者： Yining Wang Julie E. Wilson Drew Brayshaw les m. Lavkulich master of Land and Water Systems Faculty of Land and Food Systems The University of British Columbia Vancouver Canada Statlu Environmental Consulting Ltd. Chilliwack Canada

Aggregate extraction in the Lower Fraser Valley of British Columbia, Canada, has affected the soil water storage of the Pepin Creek watershed. Although local government has set regulations for aggregate extraction projects to avoid negative environmental impacts, the gradual loss of soil materials and associated changes in vegetative cover has led to an alteration of the water balance within the watershed, which may affect surface or groundwater levels, and aquatic habitats. The study assessed the effects of aggregate extraction on the water storage of the Pepin Creek watershed and estimated that 25% of the surface area of the Canadian portion of the watershed has been affected by aggregate mining with an estimated loss of water storage of 10%. Evapotranspiration has decreased as a result of the removal of the vegetative cover. Precipitation has remained relatively constant over the study period but the annual discharge measured at Pepin Creek has decreased. Recommendations for enhancing environmental monitoring to better measure and understand ecological functions of the watershed during aggregate extraction are provided.

关键词： Soil Water Storage Aggregate Extraction Water Balance Watershed Storage

Disturbance Legacy on Soil Carbon Stocks and Stability within a Coastal Temperate Forest of Southwestern British Columbia, Canada

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Open Journal of Forestry 2016年第5期6卷 305-323页

作者： Camille E. Defrenne Julie E. Wilson Suzanne W. Simard les m. Lavkulich Faculty of Forestry University of British Columbia Vancouver Canada

Although it has been recognized that soils play a critical role in carbon storage and that coastal temperate forests have considerable potential to sequester soil organic carbon (SOC), studies related to SOC stocks and stability are scarce in these ecosystems. Forest disturbances may leave legacies on SOC properties and may further compromise SOC storage capacity of these ecosystems. In the Pacific Spirit Regional Park of southwestern British Columbia, we compared SOC stocks and stability among three second-growth forests that have been affected by disturbances of different magnitudes. We collected data on soil chemical and physical properties to estimate SOC content and assess SOC stability. We found that SOC stocks in the forest characterized by low magnitude disturbance were greater than those of the forest characterized by high magnitude disturbance (8.2 ± 1.3 kg·Cm-2 versus 5.3 ± 0.1 kg·Cm-2 to 30 cm depth). SOC was less stable in the highly disturbed forest and subsequent vegetation changes might have further reduced SOC stability. Our results provide insight into the role of disturbance history in the current SOC storage capacity of coastal temperate rainforests of British Columbia.

关键词： Soil Carbon Coastal Forest Disturbances History Carbon Storage Carbon Stocks

maternal Body Composition and Its Relationship to Infant Breast milk Intake in Rural Pakistan

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Food and Nutrition Sciences 2011年第9期2卷 932-937页

作者： Nafeesa Nazlee Rakhshanda Bilal Zahid Latif les Bluck Pakistan Institute of Nuclear Science and Technology Islamabad Pakistan.

Some women in rural Pakistan are chronically undernourished, and consequently underweight. Concerns have been expressed that the degree of undernourishment might be sufficiently severe to affect lactation performance. We have obtained data on maternal body composition and infant breast milk intake using stable isotope methods in a group of thirty three mother and infant pairs at approximately six months of age. The maternal body mass index ranged from 16.6 to 29.1 kg·m-2. In this population we found that exclusive breast-feeding tended to be associated with lower maternal body fat, and that there was no evidence for compromised lactational performance due to malnourishment. Finally we note that when our data is combined with that from other studies there may be a generalised negative correlation between breast milk intake and maternal body fat.

关键词： Stable Isotopes Breast milk Intake maternal Body Composition