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modeling visitor use on high elevation mountain trails: An example from Longs Peak in Rocky mountain National Park, USA

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Journal of mountain Science 2019年第12期16卷 2882-2893页

作者： david PETTEBONE ashley D'ANTONIO Abigail SISNEROS-KIDD Christopher mONZ National Park Service Natural Resources Stewardship and ScienceEnvironmental Quality DivisionSocial Science Program80525 Fort CollinsColoradoUSA Oregon State University Department of Forest Ecosystems and Society97331 CorvallisOregonUSA Utah State University Quinney College of Natural Resources84322 LoganUtahUSA Current Affiliation:University of Wyoming Haub School of Environment and Natural Resources82072 LaramieWyomingUSA

Increasing use on mountain summits has both social and ecological *** numbers of visitors climbing mountain summits can be a safety issue,particularly in areas where terrain or elevation leads to queueing that may cause time *** visitor use levels at site specific locations en route to summits is needed to understand the potential benefits and impacts of visitor use in these ***,it can be difficult to obtain reliable and robust data to estimate use and develop statistical relationships because of the remote and harsh climates on mountain summits,as well as the financial and personnel requirements involved to collect the data in remote *** 2015,data were collected on the higher stretches of the Keyhole Route on Longs Peak in Rocky mountain National Park,USA(RmNP)to better understand use levels near the summit and to explore potential statistical relationships to trailhead use data that are relatively easy to *** statistical relationships from robust regression analyses were found between trailhead use counts and daily and hourly use totals on the"Homestretch"which is a final section of the Keyhole ***,a strong statistical relationship was found between total daily use and maximum hourly use on the *** results suggest that trailhead counts are an accurate and reliable means from which to estimate use levels on upper portions of the Keyhole ***,this research demonstrates the usefulness of an approach using proxy variables to estimate visitor use along remote peaks where data collection can be *** types of data can elucidate various options and decisions for park management teams who are charged with deciding if and how to manage high use areas.

关键词： Visitor use mountain summits National parks Use estimation Recreation use Proxy variables

Trait-based representation of hydrological functional properties of plants in weather and ecosystem models

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Plant Diversity 2017年第1期39卷 1-12页

作者： ashley m. matheny Golnazalsadat mirfenderesgi Gil Bohrer Department of Civil Environmental and Geodetic Engineering The Ohio State University Columbus OH USA

Land surface models and dynamic global vegetation models typically represent vegetation through coarse plant functional type groupings based on leaf form, phenology, and bioclimatic limits. Although these groupings were both feasible and functional for early model generations, in light of the pace at which our knowledge of functional ecology, ecosystem demographics, and vegetation-climate feedbacks has advanced and the ever growing demand for enhanced model performance, these groupings have become antiquated and are identified as a key source of model uncertainty. The newest wave of model development is centered on shifting the vegetation paradigm away from plant functional types(PFTs)and towards flexible trait-based representations. These models seek to improve errors in ecosystem fluxes that result from information loss due to over-aggregation of dissimilar species into the same functional class. We advocate the importance of the inclusion of plant hydraulic trait representation within the new paradigm through a framework of the whole-plant hydraulic strategy. Plant hydraulic strategy is known to play a critical role in the regulation of stomatal conductance and thus transpiration and latent heat flux. It is typical that coexisting plants employ opposing hydraulic strategies, and therefore have disparate patterns of water acquisition and use. Hydraulic traits are deterministic of drought resilience, response to disturbance, and other demographic processes. The addition of plant hydraulic properties in models may not only improve the simulation of carbon and water fluxes but also vegetation population distributions.

关键词： Hydraulic traits Land-surface modeling Whole-plant hydraulic strategy Trait-based models Demographic models Plant functional type

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Cadmium in soybeans and the relevance to human exposure

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Journal of Environmental Sciences 2015年第11期27卷 157-162页

作者： ashley m.Newbigging Xiaowen Yan X.Chris Le Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and Pathology University of Alberta

Introduction Cadmium is considered a human carcinogen by the International Agency for Research on Cancer（IARC,1993）and the US National Toxicology Program（NTP,1997）.Cadmium contamination of food crops is a persistent issue for both the agricultural industry as well as *** is an issue for agriculture because cadmium can be present in soils naturally or as a result of industrial processes and can contaminate foods that are consumed by ***

关键词： Cadmium metals Food safety Dietary exposure Agricultural products Uptake of cadmium from soil

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian mustroph david Gimbel Jonathan Grossberg Daniel L.Barrow matthew F.Gary Ali m.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

Hand Gesture-based Artificial Neural Network Trained Hybrid Human–machine Interface System to Navigate a Powered Wheelchair

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Journal of Bionic Engineering 2021年第5期18卷 1045-1058页

作者： ashley Stroh Jaydip Desai Department of Biomedical Engineering Wichita State UniversityWichitaKS 67260USA

Individuals with cerebral palsy and muscular dystrophy often lack fine motor control of their fingers which makes it difficult to control traditional powered wheelchairs using a *** have shown the use of surface electromyography to steer powered wheelchairs or automobiles either through simulations or gaming ***,these studies significantly lack issues with real world scenarios such as user’s safety,real-time control,and efficiency of the controller *** purpose of this study was to design,evaluate,and implement a hybrid human–machine interface system for a powered wheelchair that can detect human intent based on artificial neural network trained hand gesture recognition and navigate a powered wheelchair without colliding with objects around the *** Conjugate Gradient(SCG),Bayesian Regularization(BR),and Levenberg marquart(Lm)supervised artificial neural networks were trained in offline testing on eight participants without disability followed by online testing using the classifier with highest *** Regularization architecture showed highest accuracy at 98.4%across all participants and hidden *** participants successfully completed the path in an average of 5 min and 50 s,touching an average of 22.1%of the *** proposed hybrid system can be implemented to assist people with neuromuscular disabilities in near future.

关键词： Electromyography,Artificial neural network,Hybrid control,Powered wheelchair Assistive technology,Hand gesture recognition

Exercise is mitochondrial medicine for muscle

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Sports medicine and Health Science 2019年第1期1卷 11-18页

作者： ashley N.Oliveira david A.Hood muscle Health Research Centre School of Kinesiology and Health ScienceYork UniversityTorontoOntarioCanada

mitochondria are vital organelles that provide energy for muscle *** these organelles become dysfunctional,they produce less energy as well as excessive levels of reactive oxygen species which can trigger muscle atrophy,weakness and loss of *** this review,molecular evidence is provided to show that exercise serves as a useful therapeutic countermeasure to overcome mitochondrial dysfunction,even when key regulators of organelle biogenesis are *** findings illustrate the complexity and compensatory nature of exercise-induced molecular signaling to transcription,as well as to post-transcriptional events within the mitochondrial synthesis and degradation(***)*** with the first bout of contractile activity,exercise exerts a medicinal effect to improve mitochondrial health and whole muscle function.

关键词： mitochondria muscle Exercise Health Aging metabolism Training

microRNAs: Fad or future of liver disease

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World Journal of Gastroenterology 2011年第20期17卷 2536-2542页

作者： ashley m Lakner Herbert L Bonkovsky Laura W Schrum Department of Biology University of North Carolina at Charlotte Liver Digestive and Metabolic Disorders Laboratory and the Liver-Biliary-Pancreatic Center Carolinas Medical Center Department of medicine University of North Carolina at Chapel Hill Departments of medicine and molecular Microbial and Structural Biology University of Connecticut Health Center

microRNAs (miRs) are small non-coding RNAs that regulate both mRNA and protein expression of target genes, which results in alterations in mRNA stability or translation inhibition. miRs influence at least one third of all human transcripts and are known regulators of various important cellular growth and differentiation factors. miRs have recently emerged as key regulatory molecules in chronic liver disease. This review details recent contributions to the field of miRs that influence liver development and the broad spectrum of disease, from non-alcoholic fatty liver disease to fibrosis/cirrhosis, with particular emphasis on hepatic stellate cells and potential use of miRs as therapeutic tools.

关键词： Liver Fibrosis microRNA mRNA Hepatic stellate cells

南澳大利亚克罗克威尔地区与铀-钍矿化有关的钠质花岗岩类和片麻岩

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世界核地质科学 1986年第1期 16-26页

作者： Paul m.ashley 严平兴

在克罗克威尔矿区的钠质花岗岩及伴生的钠质片麻岩中产有钍钛铀矿矿化。野外工作、矿物学和化学资料证实,这种花岗岩是片麻岩经过高度变质期间的深熔作用而形成的。钠质花岗岩大部分属过铝质的,Na2O含量高、K2O,CaO、Rb、Ba、Sr和铁镁... 详细信息

在克罗克威尔矿区的钠质花岗岩及伴生的钠质片麻岩中产有钍钛铀矿矿化。野外工作、矿物学和化学资料证实,这种花岗岩是片麻岩经过高度变质期间的深熔作用而形成的。钠质花岗岩大部分属过铝质的,Na2O含量高、K2O,CaO、Rb、Ba、Sr和铁镁元素含量低,U、Th、Nb、Ce、Y和F的含量一般较高。许多地球化学参数在成分上继承了相似的钠质片麻岩,认为它的原岩是中-酸（碱）性序列的富方沸石火山-沉积岩受变质而来。重要的铀-钍矿化只限于破碎带和角砾岩带中。矿物组合为富石英、含氟金云母及少量的氟磷灰石、钠质斜长石、铌金红石、钍钛铀矿、独居石、白云母、绿泥石、电气石和萤石。其成因类似于所谓的斑岩铜矿和网脉状钼矿床。这种矿床是在钠质花岗岩类固相线以下的冷凝过程中,由于机械破裂和角砾岩的发育而形成的。

关键词：片麻岩混合岩原岩变质岩钠质花岗岩矿化带成矿带花岗岩类罗克威尔金云母斜长石