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Multi-scale drivers of soil resistance predict vulnerability of seasonally wet meadows to trampling by pack stock animals in the Sierra Nevada,USA

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Ecological Processes 2020年第1期9卷 364-377页

作者： Joy S.Baccei Mitchel P.Mcclaran Tim J.Kuhn Stephen c.hart Environmental Systems Graduate Group University of CaliforniaMercedCA 95343USA Uc Merced Vernal Pools and Grassland Reserve UC Merced Natural Reserve SystemMercedCA 95343USA School of Natural Resources and the Environment University of ArizonaTucsonAZ 85721USA Resources Management and Science Yosemite National ParkEl PortalCA 95318USA Department of Life&Environmental Sciences and Sierra Nevada Research Institute University of CaliforniaMercedCA 95343USA.

Background:Meadow ecosystems have important ecological functions and support socioeconomic services,yet are subject to multiple stressors that can lead to rapid *** the Sierra Nevada of the western USA,recreational pack stock(horses and mules)use in seasonally wet mountain meadows may lead to soil trampling and meadow degradation,especially when soil water content is high and vegetation is ***:In order to improve the ability to predict meadow vulnerability to soil disturbance from pack stock use,we measured soil resistance(SR),which is an index of vulnerability to trampling disturbance,at two spatial scales using a stratified-random sampling *** then compared SR to several soil and vegetation explanatory variables that were also measured at the two spatial scales:plant community type(local scale)and topographic gradient class(meadow scale).Results:We found that local-scale differences in drivers of SR were contingent on the meadow scale,which is important because multiple spatial scale evaluation of ecological metrics provides a broader understanding of the potential controls on ecological processes than assessments conducted at a single spatial *** also found two contrasting explanatory models for drivers of SR at the local scale:(1)soil gravimetric water content effects on soil disaggregation and(2)soil bulk density and root mass influence on soil *** resistance was insufficient to sustain pack stock use without incurring soil deformation in wet plant communities,even when plant cover was maximal during a major ***:Our study provides new information on seasonally wet meadow vulnerability to trampling by pack stock animals using multi-scale drivers of SR,including the contrasting roles of soil disaggregation,friction,and *** work aims to inform meadow management efforts in the Sierra Nevada and herbaceous ecosystems in similar regions that are subject to seasonal soil saturation and livestock u

关键词： Hydrogeomorphic classification Hydrologic regime Pack stock Plant communities Soil properties Soil strength

SOME PHYSIcAL ASPEcTS OF ADOLEScENcE IN cHINESE STUDENTS

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中华医学杂志(英文版) 1934年第1期048卷 37-46页

作者： c.hart WESTBROOK DANIELG.LAI SIDNEY D.HSIAO UniversityofShanghai NationalMedicalcollegeofShanghai andcentralchinaUniversity respectively. UniversityofShanghai NationalMedicalcollegeofShanghai andcentralchinaUniversity respectively. UniversityofShanghai NationalMedicalcollegeofShanghai andcentralchinaUniversity respectively.

*** view of physiological and educational importance,throughquestionnaires and medical examinations,we attempted to study theadolescence of 1,000 boys and 336 girls in schools at Shanghai and *** four standard criteria of adolescence adopted for boys werethe presence of 1)pubic hairs and 2)axillary hairs,3) change of voice,and 4)night emissions;for girls,1)pubic hairs,2)axillary hairs,3)mammary development,and 4)first *** means for the four signs of puberty in boys were:1)firstemission,age 15.48±0.03 years;2)first pubic hairs,age 15.24±0.03;3) first axillary hairs,age 16.01+0.04,and 4)first signs of change ofvoice,age 15.2±*** means for the four signs of puberty in girls were:1)firstmenstruation,age 13.56±0.05 years;2)first signs of enlargement ofbreasts noted,age 13.56±0.07,3)first pubic hairs,age 14.83±0.16,and 4) first axillary hairs,age 15.33±*** the group of 665 school boys examined,pre-pubescents werefound extending over 8 years,at II years 100 per cent being pre-pubes-cent,and at 18 years,1.2 per cent;the age of pubescents ranged from12 to 19 years;and of post-pubescents,from 13 to 20 years.

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海洋环境安全:一种可持续发展的观点

厦门大学学报（自然科学版） 2004年第B8期43卷 254-257页

作者：张珞平洪华生陈伟琪刘泓 William c.hart 厦门大学海洋环境科学教育部重点实验室环境科学研究中心福建厦门361005 福建农业与林业大学资源与环境学院福建福州361005 加拿大Dalhousie大学水资源研究中心 NSB3J2X4Canada

联合国海洋环境保护科学问题联合专家组(GESAMP)是一个由八个联合国机构发起的科学顾问团体,它的报告和述评是各个联合国组织制定有关海洋政策和决策的基础.尽管GESAMP的观点近年来有很大进展,但在如何促进和改善保护海洋环境的行动等... 详细信息

联合国海洋环境保护科学问题联合专家组(GESAMP)是一个由八个联合国机构发起的科学顾问团体,它的报告和述评是各个联合国组织制定有关海洋政策和决策的基础.尽管GESAMP的观点近年来有很大进展,但在如何促进和改善保护海洋环境的行动等问题仍有它的局限性.本文提出了"海洋环境安全"的概念,以促进海洋环境保护和海洋资源的可持续利用,并讨论了海洋环境研究和海洋环境管理应采取的行动.

关键词：海洋环境安全可持续发展海洋污染海洋环境保护持续性原则海洋资源

Altered O-GlcNAcylation and mitochondrial dysfunction,a molecular link between brain glucose dysregulation and sporadic Alzheimer's disease

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Neural Regeneration Research 2023年第4期18卷 779-783页

作者： chia-Wei Huang Nicholas c.Rust Hsueh-Fu Wu Gerald W.hart complex carbohydrate Research center University of GeorgiaAthensGAUSA Department of Biochemistry and Molecular Biology University of GeorgiaAthensGAUSA center for Molecular Medicine University of GeorgiaAthensGAUSA

Alzheimer’s disease is a neurodegenerative disease that affected over 6.5 million people in the United States in 2021,with this number expected to double in the next 40 years without any sort of *** to its heterogeneity and complexity,the etiology of Alzheimer’s disease,especially sporadic Alzheimer’s disease,remains largely *** evidence suggests that brain glucose hypometabolism,preceding Alzheimer’s disease hallmarks,is involved in the pathogenesis of Alzheimer’s ***,we discuss the potential causes of reduced glucose uptake and the mechanisms underlying glucose hypometabolism and Alzheimer’s disease ***,decreased O-Glc NAcylation levels by glucose deficiency alter mitochondrial functions and together contribute to Alzheimer’s disease *** major problem with Alzheimer’s disease research is that the disease progresses for several years before the onset of any symptoms,suggesting the critical need for appropriate models to study the molecular changes in the early phase of Alzheimer’s disease ***,this review also discusses current available sporadic Alzheimer’s disease models induced by metabolic abnormalities and provides novel directions for establishing a human neuronal sporadic Alzheimer’s disease model that better represents human sporadic Alzheimer’s disease as a metabolic disease.

关键词： Alzheimer’s disease amyloid beta brain glucose deficiency glucose uptake hypometabolism mitochondrial dysfunction neurodegenerative disease neurons O-GlcNAc Tau

Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

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Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin G.Willson Lauren E.cox Justin L.hart Daniel c.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Department of Environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an EF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba L.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,pcated that understory light penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

Disturbance history,species diversity,and structural complexity of a temperate deciduous forest

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Journal of Forestry Research 2020年第2期31卷 397-414页

作者： Jonathan D.Goode carson R.Barefoot Justin L.hart Daniel c.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Stand structural complexity enhancement is an increasingly popular management objective,especially on public *** stand structures are hypothesized to support a relatively high degree of native forest diversity and be more resistant and resilient to *** structures are characterized by the presence of deadwood and heterogeneity of tree-size classes and tree *** little is known about how discrete disturbance events affect structural complexity and compositional diversity in Quercus-dominated stands at fine spatial scales(***).We established 200.05 ha fixed-radius plots on the Sipsey Wilderness of William *** National Forest in northern Alabama to quantify woody plant species composition and *** were mapped on each plot to quantify overstory structural complexity and compositional *** extracted two cores from all canopy Quercus spp.c 5 cm diameter at breast height to quantify age,recruitment pulses,and reconstruct canopy disturbance *** species diversity in the sampled area was 1.75 for trees,2.08 for saplings,and 1.69 for *** alba had the greatest basal area,and Ostrya virginiana had the highest *** stand exhibited a reverse J-shaped distribution with a q-factor of *** oldest Quercus dated to 1795,and the largest recruitment pulse occurred in the *** mean return interval for intermediateseverity disturbance was 38 *** we documented no relationships between disturbance frequency and compositional diversity at the neighborhood scale(0.05 ha),less frequent disturbance was associated with higher structural complexity(r^2=0.258,p=0.026)at the neighborhood *** suggest that localized disturbance increases species diversity and structural complexity,but these processes are manifest at the stand level and not at the neighborhood *** conclude that the spatial variability(***,shape,orientation,microsite conditions)is likel

关键词： canopy gap Quercus(oak) Stand development Succession

Macro-and microcirculation patterns of intrahepatic blood flow changes in patients with hereditary hemorrhagic telangiectasia

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World Journal of Gastroenterology 2017年第3期23卷 486-495页

作者： Roland c Schelker Ana P Barreiros christina hart Wolfgang Herr Ernst-Michael Jung Department of Internal Medicine III Hematology and OncologyUniversity Hospital of Regensburg93051 RegensburgGermany Ernst-Michael Jung Department of RadiologyUniversity Hospital of Regensburg93051 RegensburgGermany

AIM To evaluated vascular dynamic processes in the liver of hereditary hemorrhagic telangiectasia(HHT) patients by ultrasound(US) considering quantitative analytic methods. METHODS The imaging features on US and contrast-enhanced ultrasound(cEUS) in 18 patients diagnosed with HHT were retrospectively analyzed. Regarding cEUS, realtime contrast harmonic imaging and sulfur hexafluoridefilled microbubbles were used. RESULTS HVa Ms were identified in all 18 patients. By US, the two major caselitz criteria could be detected in 55.6% patients. "color spots" were detected in 72.2% of the cases. Respecting sonographic grading criteria by Buscarini, grade 3 could be demonstrated most frequent(40%). By cEUS, all the patients showed quick and early hyperenhancement during the arterial phase. Significant lowest time to peak(TTP) and highest area under the curve(AUc) values were identified in the hepatic artery(TTP: 69.8%; AUc: 100%) and highest TTP and lowest AUc in the hepatic parenchyma and the portal vein. cONcLUSION For the first time we analyzed cEUS findings of a group of HHT patients regarding macro- and microcirculation. Our data demonstrate significant differences in TTP and AUc values in the four selected regions: hepatic artery, shunt region, portal vein and hepatic parenchyma.

关键词： Hereditary hemorrhagic telangiectasia Intrahepatic shunts contrast-enhanced ultrasound Time-intensity-curve

Additive manufacturing of flexible 3D surface electrodes for electrostatic adhesion control and smart robotic gripping

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摩擦:英文版 2023年第11期11卷 1974-1986页

作者： Dong Geun KIM Hyeongmin JE AJohn hart Sanha KIM Department of Mechanical Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Mechanically flexible surface structures with embedded conductive electrodes are attractive in contact-based devices,such as those used in reversible dry/adhesion and tactile *** shapes of the surface structures strongly determine the contact behavior and therefore the resulting adhesion and sensing functionalities;however,available features are often restricted by fabrication ***,we additively manufacture elastomeric structure arrays with diverse angles,shapes,and sizes;this is followed by integration of conductive nanowire *** fabricated flexible three-dimensional(3D)surface electrodes are mechanically compliant and electrically conductive,providing multifunctional ability to sense touch and to switch adhesion via a combined effect of shear-and electro *** designed soft,anisotropic flexible structures to mimic the gecko’s reversible adhesion,which is governed by van der Waals forces;we integrated nanowires to further manipulate the localized electric field among the adjacent flexible 3D surface electrodes to provide additional means to digitally tune the electrostatic attraction at the contact *** addition,the composite surface can sense the contact force via capacitive *** our flexible 3D surface electrodes,we demonstrate a complete soft gripper that can grasp diverse convex objects,including metal,ceramic,and plastic products,as well as fresh fruits,and that exhibits 72%greater electroadhesive gripping force when voltage is applied.

关键词： electroadhesion tactile sensing robotic gripper additive manufacturing dry adhesive

Primary parasitoids of red scale （Aonidiella aurantii） in Australia and a review of their introductions from Asia

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Insect Science 2017年第1期24卷 150-168页

作者： Hang T. Dao G. Andrew c. Beattie Robert Spooner-hart Markus Riegler Paul Holford University of Western Sydney Penrith NSW 2751 Australia Plant Protection Research Institute Chem Tu Liem Hanoi Vietnam

We used morphological and molecular differences to confirm the identities of red scale （Aonidiella aurantii） and yellow scale （A. citrina）, and their primary parasitoids, in Australia. An extension to the distribution of yellow scale was confirmed. Six primary parasitoids of red scale were identified： Aphytis chrysomphali, A. lingnanensis, A. melinus, comperiella bifasciata, Encarsia citrina, and E. perniciosi. With the exception of A. lingnanensis, these parasitoids, and a species of Aphelinus, were detected in association with red scale during studies in citrus orchards in coastal New South Wales between 2009 and 2012. Two races ofA. melinus were recorded： one from the Indian Subcontinent, the other previously only recorded in china. The studies, and reviews of historical records, led us to conclude that 4 parasitoids, A. lingnanensis, c. bifasciata, and both species of Encarsia, were present in Australia before successful or unsuccessful formal introductions between 1902 and 1970. The A. melinus race previously recorded in china may also have been present before the Indian Subcontinent race was formally introduced in 1961. We suggest the possibility that the natural distribution of some of the parasitoids may include East and Southeast Asia, and parts of Australasia. We found no reports of native armored scales being recorded on species and hybrids of citrus introduced to Australia, and no reports of introduced armored scales being recorded on native Rutaceae, including 6 species of citrus. However, we subsequently recorded yellow scale on Geijera parviflora, a native rutaceous tree.

关键词： Aonidiella Aphytis citrus comperiella Encarsia red scale