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Does a shift in shade tolerance as suggested by seedling morphology explain differences in regeneration success of northern red oak in native and introduced ranges?

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journal of Forestry Research 2022年第3期33卷 949-962页

作者： peter Nosko Kerri Moreau Christian Kuehne Kelly C.Major jürgen Bauhus Department of Biology and Chemistry Nipissing UniversityNorth BayONP1B 8L7Canada Chair of Silviculture Freiburg University79085FreiburgGermany Division of Forestry and Forest Resources Norwegian Institute of Bioeconomy ResearchP.O.Box 1151431ÅsNorway Tulloch Engineering 1942 Regent StUnit LSudburyONP3E 5V5Canada

Across North America, forests dominated by Quercus rubra L. (northern red oak), a moderately shade-tolerant tree species, are undergoing successional replacement by shade-tolerant competitors. Under closed canopies, Q. rubra seedlings are unable to compete with these shade-tolerant species and do not recruit to upper forest strata. In Europe, natural regeneration of introduced Q. rubra is often successful despite the absence of fire, which promotes regeneration in the native range. Considering that understorey light availability is a major factor affecting recruitment of seedlings, we hypothesized that Q. rubra seedlings are more shade tolerant in the introduced range than in the native range. Morphological traits and biomass allocation patterns of seedlings indicative of shade tolerance were compared for Q. rubra and three co-occurring native species in two closed-canopy forests in the native range (Ontario, Canada) and introduced range (Baden-Württemburg, Germany). In the native range, Q. rubra allocated a greater proportion of biomass to roots, while in the introduced range, growth and allocation patterns favored the development of leaves. Q. rubra seedlings had greater annual increases in height, diameter and biomass in the introduced range. Q. rubra seedlings in the introduced range were also younger;however, they had a mean area per leaf and a total leaf area per seedling that were five times greater than seedlings in the native range. Such differences in morphological traits and allocation patterns support the hypothesis that Q. rubra expresses greater shade tolerance in the introduced range, and that natural regeneration of Q. rubra is not as limited by shade as in the native range. The ability of Q. rubra seedlings to grow faster under closed canopies in Europe may explain the discrepancy in regeneration success of this species in native and introduced ranges. Future research should confirm findings of this study over a greater geographical range in native

关键词： Alien species Cross-continental study Forest regeneration Introduced species Seedling morphology Plant functional traits Quercus rubra

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Seasonal resource selection of an arboreal habitatspecialist in a human-dominated landscape: A case studyusing red panda

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Current Zoology 2023年第1期69卷 1-11页

作者： Damber Bista Greg S.Baxter Nicholas j.Hudson peter j.Murray School of Agriculture and Food Sciences(Wildlife Science Unit) The University of QueenslandGattonQLD 4343Australia School of Agriculture and Environmental Science University of Southern QueenslandDarling HeightsQLD 4350Australia

Human-dominated landscapes provide heterogeneous wildlife habitat. Conservation of habitat specialists, like red pandas Ailurus fulgens, inhabiting such landscapes is challenging. Therefore, information on resource use across spatial and temporal scales could enable informed-decisionmaking with better conservation outcomes. We aimed to examine the effect of geo-physical, vegetation, and disturbance variables on fine-scalehabitat selection of red pandas in one such landscape. We equipped 10 red pandas with GPS collars in eastern Nepal in 2019 and monitoredthem for 1 year. Our analysis was based on a generalized-linear-mixed model. We found the combined effect of geo-physical, vegetation, anddisturbance variables resulted in differences in resource selection of red pandas and that the degree of response to these variables variedacross seasons. Human disturbances, especially road and cattle herding activities, affected habitat utilization throughout the year whereas othervariables were important only during restricted periods. For instance, geo-physical variables were influential in the premating and cub-rearingseasons while vegetation variables were important in all seasons other than premating. Red pandas selected steeper slopes with high solarinsolation in the premating season while they occupied elevated areas and preferred specific aspects in the cub-rearing season. Furthermore,the utilized areas had tall bamboo in the birthing and cub-rearing seasons while they also preferred diverse tree species and high shrub coverin the latter. Our study demonstrates the significance of season-specific management, suggests the importance of specific types of vegetationduring biologically crucial periods, and emphasizes the necessity to minimize disturbances throughout the year.

关键词： Ailurus fulgens anthropogenic disturbances habitat specialists habitat utilization resource use spatio-temporal variation vegetation

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Light metal compound casting

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Science China(Technological Sciences) 2009年第1期52卷 46-51页

作者： Konrad j. M. PAPIS joerg F. LOEFFLER peter j. UGGOWITZER ETH Zurich Laboratory of Metal Physics and Technology Wolfgang-Pauli-Str. 10

‘Compound casting’simplifies joining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as joint structures of spaceframe constructions in transport industry. In this project, ‘compound casting’ of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu- ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the joining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and Al12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protective coating to the substrate.

关键词： compound casting aluminium alloys magnesium alloys interface structure

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Quantum model simulations of attosecond electron diffraction

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Science China(Physics,Mechanics & Astronomy) 2010年第6期53卷 987-1004页

作者： peter BAUM jrn MANZ Axel SCHILD Max-Planck-Institute of Quantum Optics and Ludwig-Maximilians-Universitt München Freie Universitt Berlin Institut für Chemie und Biochemie

Ultrafast diffraction with free attosecond electron pulses promises insight into the four-dimensional motion of charge density inatoms,molecules and condensed matter. Here we consider the quantum dynamics of the electron-electron scattering process on anattosecond time scale. By numerically solving the time-dependent two-electron Schrdinger equation,we investigate the interactionof an incoming keV-range electron wavepacket by the bound electron of an aligned H+2 molecule,using a one-dimensional *** findings reveal the ratio of elastic to inelastic contributions,the role of exchange interaction,and the influence of the molecularelectron density to diffraction. Momentum transfer during the scattering process,from the incoming to the bound electron mediatedby the nuclei,leaves the bound electron in a state of coherent oscillation with attosecond recurrences. Entanglement causes relatedstate-selective oscillations in the phase shift of the scattered electron. Two scenarios of distinguishable and indistinguishable freeand bound electrons yield equivalent results,irrespective of the electronic spins. This suggests to employ the scenario of distinguishable electrons,which is computationally less demanding. Our findings support the possibility of using electron diffraction forimaging the motion of charge density,but also suggest the application of free electron pulses for inducing attosecond dynamics.

关键词： ultrafast electron diffraction scattering theory attosecond dynamics entanglement coherence

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Storylines of family medicine Ⅱ:foundational building blocks—context,community and health

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Family Medicine and Community Health 2024年第S3期12卷 12-22页

作者： William B Ventres Leslie A Stone Rupal Shah Tamala Carter Geoffrey M Gusoff Winston Liaw Bich-May Nguyen joanna V Rachelson Mary Alice Scott Teresa L Schiff-Elfalan Seiji Yamada Robert C Like Kathleen Zoppi A peter Catinella Richard M Frankel Shailendra Prasad Family and Preventive Medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA Bridge Lane Group Practice LondonUK Penn Center for Community Health Workers University of PennsylvaniaPhiladelphiaPennsylvaniaUSA National Clinician Scholars Program UCLA David Geffen School of MedicineLos AngelesCaliforniaUSA Health Systems and Population Health Sciences University of Houston Tilman J Fertitta Family College of MedicineHoustonTexasUSA Southern New Mexico Family Medicine Residency Program Las CrucesNew MexicoUSA New Mexico Primary Care Training Program Silver CityNew MexicoUSA Anthropology New Mexico State UniversityLas CrucesNew MexicoUSA Family Medicine and Community Health University of Hawai'i at Manoa John A Burns School of MedicineHonoluluHawaiiUSA Family Medicine and Community Health Rutgers Robert Wood Johnson Medical SchoolNew BrunswickNew JerseyUSA Family Medicine Indiana University School of MedicineIndianapolisIndianaUSA Family Medicine–Transmountain Texas Tech University Health Sciences CenterEl PasoTexasUSA Medicine Indiana University School of MedicineIndianapolisIndianaUSA Family Medicine and Community Health University of Minnesota Medical School-Twin Cities CampusMinneapolisMinnesotaUSA

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅱ:foundational building blocks—context,community and health’,authors address the following themes:‘Context—grounding family medicine in time,place and being’,‘Recentring community’,‘Community-oriented primary care’,‘Embeddedness in practice’,‘The meaning of health’,‘Disease,illness and sickness—core concepts’,‘The biopsychosocial model’,‘The biopsychosocial approach’and‘Family medicine as social medicine.’May readers grasp new implications for medical education and practice in these essays.

关键词： thematic illustration dimensions

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Preliminary Insights into the Habitat Preferences of the Centralian Bandy Bandy (Vermicella vermiformis)(Squamata: Elapidae) in Central Australia

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Asian Herpetological Research 2014年第1期5卷 49-53页

作者： peter j.MCDONALD Gary W.LUCK Flora and Fauna Division Department of Land Resource Management Northern Territory Government School of Environmental Sciences Charles Sturt University Institude for Land Water and Society Charles Sturt University

Bandy Bandy’s（Vermicella spp.）are a striking,black-and-white ringed genus of small elapid snakes endemic to *** taxa are burrowers and little is known of their biology and *** investigated the habitat preferences of the only arid-dwelling species,the centralian bandy bandy（Vermicella vermiformis）,in the MacDonnell Ranges west of Alice Springs in the Northern *** systematic road-cruising,we encountered *** over a 12 months period between 2009 and *** used logistic regression to model the occurrence of the species against a range of different habitat variables collected at multiple *** the small sample size,*** exhibited a clear preference for acacia shrubland habitats,with acacia variables present in all AICc ranked models in the 95%confidence *** factors driving this association,together with the preference for habitat not burnt in the most recent wildfires,may be related to the abundance of their only known prey,blind snakes（Ramphotyphlops spp.）.

关键词： Snake Arid Acacia Fire Ramphotyphlops

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Another look at social innovation:From community-For community

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International journal of Innovation Studies 2022年第2期6卷 92-101页

作者： Lisa j.Daniel peter jenner School of Business and Creative Industries University of the Sunshine CoastFraser CoastQueensland4655Australia

Social innovation(SI)continues to raise interest among scholars and policymakers,as a potential panacea for social disenfranchisement and civic *** is troubling is diverse perspectives of SI abound,creating inconsistencies in methodological approaches which confound theory *** paper clarifies that discussion by considering the locus of initiation and locus of benefit as informing characteristics that differentiate grounded social innovation from other types of well-recognized socially beneficent *** notion of‘from community e for community’is presented to aid understanding of the unique nature of authentically grounded social *** paper is significant as it presents a practical approach to help researchers and practitioners consider where opportunities for targeted policy support,institutional involvement,and agency action can aid community development and wellbeing.

关键词： Social innovation Community markets Social change Community development

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Preface: Metamorphism and Orogenic Belts——Response from Micro-to Macro-Scale

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journal of Earth Science 2019年第6期30卷 1075-1083页

作者： Xu-Ping Li Hans-peter Schertl jürgen Reinhardt Shandong Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590China Ruhr-University Bochum Institute of GeologyMineralogy and GeophysicsD-44780 BochumGermany College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Department of Earth Sciences University of the Western CapeBellville 7535South Africa

The geological toolbox for the analysis of orogenic processes has seen substantial additions over the recent *** advances have been made in the ability to simulate geological conditions and processes by computer modeling,we have a much improved knowledge of geochemical processes(trace elements and isotopes in particular),and,last but not least,the range and versatility of micro-analytical methods and instrumentation available to us has been expanded *** latter aspect has had a particular impact on metamorphic petrology as the conventional tools to determine pressure-temperaturetime paths via rock and mineral analysis combined with isotope geochronology have generally gained in precision and accuracy through a much improved *** has moved from whole-grain analysis to spot analyses on zoned single grains while analyzing trace elements and isotopes at the same *** is therefore possible to recognize complex multi-stage orogenic events in single samples or single *** profiles in minerals provide us with time-scales of metamorphic and magmatic *** and trace elements as well as isotope profiles of mineral grains give us insight into changing ambient conditions during mineral *** special issue focuses on pressure-temperature conditions and geochronology of metamorphic rocks,isotope studies of magmatic rocks,partial melting and metasomatic processes,all with a view at tectonic implications and *** of the evidence has been gained from small-scale observation and *** field work and detailed microscopic examination remain indispensable,though,as demonstrated clearly by the"expansion"of the P-T space as applicable to crustal metamorphic processes towards extreme pressures and *** a consequence,much interest has thus focused on UHP and UHT rocks and the orogenic processes that generate *** is petrological evidence for subduction to,and subsequent exhumation fr

关键词： orogeny metasomatism UHP metamorphism UHT metamorphism geochemistry geochronology

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Does knowledge of physical activity recommendations increase physical activity among Chinese college students？ Empirical investigations based on the transtheoretical model

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journal of Sport and Health Science 2018年第1期7卷 77-82页

作者： Kahar Abula peter Gropel Kai Chen jürgen Beckmann Technical University of Munich Munchen 80992 Germany South West jiao Tong University Chengdu 611756 China

Background: Based on the transtheoretical model, the current study investigated whether awareness of physical activity(PA) recommendations had an impact on the stages of PA behavior change and levels of PA among Chinese college ***: In Study 1, with a cross-sectional study design, 9826 students were recruited, and their knowledge of international PA recommendations,PA stage distribution, and self-reported PA level were surveyed. Pearson's χ2 test was used to test whether those participants who were aware and not aware of PA guidelines were equally distributed across the stages of PA behavior, and independent t test was conducted to test the group difference in the actual levels of PA. In Study 2, 279 students who were not aware of the PA recommendations were randomly allocated to either an intervention group or a control group, and only those in the intervention group were presented with international PA guidelines. In both groups,students' PA stages and PA level were examined before the test and then 4 months post-test. Mc Nemar's test for correlated proportions and repeated-measures analysis of variance were conducted to examine the changes in PA stage membership and PA level after the ***: Study 1 results revealed that only 4.4% of the surveyed students had correct knowledge of PA recommendations. Those who were aware of the recommendations were in later stages of PA behavior(χ~2(4) = 167.19, p < 0.001). They were also significantly more physically active than those who were not aware of the recommendations(t(443.71) = 9.00, p < 0.001, Cohen's d = 0.53). Study 2 results demonstrated that the intervention group participants who were at the precontemplation and contemplation stages at the pre-test each progressed further in the PA stages in the post-test(χ~2(1) = 112.06, p < 0.001; χ~2(1) = 118.76, p = 0.03, respectively), although no significant change in PA level was observed(t(139) < 1, p = 0.89).Conclusion: The results showed that

关键词： Behavior change Physical activity level Physical activity recommendations Public health policy Stages of change Transtheoretical model

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Neurological consequences of systemic inflammation in the premature neonate

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Neural Regeneration Research 2017年第6期12卷 890-896页

作者： Aparna Patra Hong Huang john A.Bauer peter j.Giannone OMNI Academic Service Line and Division of Neonatology Department of Pediatrics Kentucky Children's Hospital College of MedicineUniversity of Kentucky

Despite substantial progress in neonatal care over the past two decades leading to improved survival of extremely premature infants, extreme prematurity continues to be associated with long term neurodevelopmental impairments. Cerebral white matter injury is the predominant form of insult in preterm brain leading to adverse neurological consequences. Such brain injury pattern and unfavorable neurologic sequelae is commonly encountered in premature infants exposed to systemic inflammatory states such as clinical or culture proven sepsis with or without evidence of meningitis, prolonged mechanical ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis and chorioamnionitis. Underlying mechanisms may include cytokine mediated processes without direct entry of pathogens into the brain, developmental differences in immune response and complex neurovascular barrier system that play a critical role in regulating the cerebral response to various systemic inflammatory insults in premature infants. Understanding of these pathologic mechanisms and clinical correlates of such injury based on serum biomarkers or brain imaging findings on magnetic resonance imaging will pave way for future research and translational therapeutic opportunities for the developing brain.

关键词： premature consequences inflammation prematurity extremely translational dysplasia sepsis necrotizing neurological

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