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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

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Adoption of HpAI biosecurity measures： The Chinese broiler industry

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Journal of Integrative Agriculture 2017年第1期16卷 181-189页

作者： HUANG Ze-ying Adam Loch christopher Findlay WANG Ji-min Institute of Agricultural Economics and Development Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Centre for Global Food and Resources University of Adelaide Adelaide 5005 South Australia Faculty of the professions University of Adelaide Adelaide 5005 South Australia

Highly pathogenic avian influenza （HpAI） contamination via wild birds and rodents poses a threat to food security and safety. As chicken meat comprises an increasing proportion of diet in China, it is useful to determine whether broiler farmers are adopting wild bird and rodent controls to minimize the risk of HpAI impacts on food supply. Our study surveyed a cross sectional sample of 331 Chinese broiler farmers in six provinces. We find that only 47% of farmers （mainly farmers with large herds） adopted control measures against wild birds and rodents, while 14% adopted no measures. Farm size was the biggest driver of adoption followed by proportion of farm revenue derived from broiler production. However, southern farmers were at a far greater probability of non-adoption. We suggest that assistance in the form of education/training programs and subsidized traps or baiting controls across smaller producers could help raise of the adoption level toward more effective HpAI control.

关键词： highly pathogenic avian influenza broiler farmers livestock disease biosecurity adoption

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Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes

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Journal of Mountain Science 2019年第2期16卷 243-255页

作者： Derek J.MARTIN christopher ELY Beverley C.WEMpLE Department of Geography and planning Appalachian State University Department of Geography University of Vermont

The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo?s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information Systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment(22.7 km^2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns(dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems.

关键词： Bank erosion páramo Fluvial geomorphology Andes

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Cardiac remodeling as a consequence of atrial fibrillation： An anatomical study of perfusion-fixed human heart specimens

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Journal of Geriatric Cardiology 2011年第3期8卷 141-146页

作者： christopher D Rolfes Stephen A Howard Ryan p Golf paul A Iaizzo Department of Biomedical Engineering University of Minnesota Minneapolis MAr 55455 USA Department of Surgery University of Minnesota Minneapolis MN55455 USA Department of Integrative Biology and physiology University of Minnesota Minneapolis MN 55455 USA

Background Atrial fibrillation （AF） causes a continuum of atrial anatomical remodeling. Methods Using a library of perfusion-fixed human hearts, specimens with AF were compared to controls. During this preliminary assessment study, direct measurements were taken of atrial volume, pulmonary vein （pV） circumference, and left atrial （LA） wall thicknesses. Results Hearts with AF typically had larger atrial volumes, as well as a much larger variation in volume compared to controls （range of 59.6-227.1 mL in AF hearts compared to 65.1-115.9 mL in controls）. For all hearts, right pVs were larger than left pVs （mean： 171.4 ± 84.6 mm^2 for right and 1182 ± 50.1 mm^2 for left, p 〈 0.005）. LA wall thicknesses ranged from 0.7 mm to 3.1 mm for both AF and control hearts. Conclusions Hearts with AF had a large range of sizes which is consistent with the progression of atrial remodeling during AF. The large range of thicknesses will influence the amount of energy needed to create transmural lesions during ablation procedures.

关键词： left atrial dimensions volumes pulmonary vein ostia atrial fibrillation

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Exploring the molecular landscape of NNK-induced transformation:A comprehensive genome-wide CRISpR/Cas9 screening

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Genes & Diseases 2024年第4期11卷 42-44页

作者： Trang Dinh Mira Rahm Zhenghe Wang christopher McFarland Athar Khalil Department of Genetics and Genome Sciences Case WesternReserve UniversityClevelandOH44106USA

Lung cancer is the leading cause of cancer-related deaths worldwide,with an estimated 1.8 million deaths in 2020 alone.1 While several risk factors are associated with lung cancer,smoking remains the most significant environmental cause of the disease.1 One of the most potent carcinogens in tobacco smoke is 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone(NNK),which is produced from nicotine through a series of metabolic reactions.

关键词： CRISpR/Cas9 NNK lung

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Expression of the tyrosine kinase receptor EphA5 and its ligand ephrin-A5 during mouse spinal cord development

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Neuroscience Bulletin 2007年第5期23卷 249-255页

作者： christopher p.WASHBURN Margaret A.COOpER 周仁平罗格斯新泽西州立大学 Ernest Mario药学院生物化学系Susan Lehman Cullman癌症研究实验室

Objectives To study the expression patterns of two Eph family molecules, the receptor EphA5, and the ligand ephrin-A5, during spinal cord development. Methods The receptor expression was analyzed using beta-galactosidase knockin mice, and affinity ligand probe binding. The ligand expression was assessed using two different affinity probes, and knockout mouse tissues as controls. Results EphA5 was expressed in the ventral spinal cord, while ephrin-A5 was located in the dorsolateral regions of the spinal cord throughout development. Conclusions These results show that EphA5 and ephrin-A5 are expressed over broad developmental stages and may play important roles in establishing the dorsoventral organization of the spinal cord.

关键词： axon guidance embryogenesis dorsal root ganglion histochemistry alkaline phosphatase affinity probe β-galactosidase

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Octave-spanning coherent supercontinuum generation in silicon on insulator from 1.06μm to beyond 2.4μm

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Light(Science & Applications) 2017年第1期6卷 235-242页

作者： Neetesh Singh Ming Xin Diedrik Vermeulen Katia Shtyrkova Nanxi Li patrick T Callahan Emir Salih Magden Alfonso Ruocco Nicholas Fahrenkopf christopher Baiocco Bill p-p Kuo Stojan Radic Erich Ippen Franz X Kärtner Michael R Watts Research Laboratory of Electronics Massachusetts Institute of TechnologyCambridgeMA 02139USA John A.paulson School of Engineering and Applied Science Harvard UniversityCambridgeMA 02138USA College of Nanoscale Science and Engineering SUNY Polytechnic InstituteAlbanyNY 12203USA Department of Electrical and Computer Engineering University of California San DiegoLa JollaCA 92039USA Centre for Free Electron Laser Science(CFEL)-DESY and University of Hamburg Hamburg 22607Germany

Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong *** to two-photon absorption in silicon,however,much nonlinear research is shifting towards unconventional photonics *** this work,we demonstrate the generation of an octave-spanning coherent supercontinuum in a silicon waveguide covering the spectral region from the near-to *** input pulses of 18 pJ in energy,the generated signal spans the wavelength range from the edge of the silicon transmission window,approximately 1.06 to beyond 2.4μm,with a−20 dB bandwidth covering 1.124–2.4μ*** octave-spanning supercontinuum was also observed at the energy levels as low as 4 pJ(−35 dB bandwidth).We also measured the coherence over an octave,obtaining|g_()12^(1)(λ)>90%,in good agreement with the *** addition,we demonstrate optimization of the third-order dispersion of the waveguide to strengthen the dispersive wave and discuss the advantage of having a soliton at the long wavelength edge of an octave-spanning signal for nonlinear *** research paves the way for applications,such as chip-scale precision spectroscopy,optical coherence tomography,optical frequency metrology,frequency synthesis and wide-band wavelength division multiplexing in the telecom window.

关键词： coherence integrated photonics silicon supercontinuum

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Considerations for Implementing OGC WMS and WFS Specifications in a Desktop GIS

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Journal of Geographic Information System 2012年第2期4卷 161-167页

作者： christopher D. Michaelis Daniel p. Ames Department of Geosciences Idaho State University Idaho Falls USA

An implementation of the Open Geospatial Consortium Web Feature Service (WFS) and Web Map Service (WMS) specifications in an open source desktop GIS is presented together with a discussion of considerations for improving the use of web services data in desktop applications. In our implementation, WFS and WMS services are consumed by a plug-in to MapWindow GIS [1], allowing the end user to view WFS, WMS and ArcIMS data, including data from the ESRI Geography Network, in a transparent manner that can be configured for either data analysis and modeling, or data visualization. This implementation in an open source GIS allows for others to view and use the code, improve it, and otherwise implement the suggested considerations in other GIS platforms. Specific considerations proposed here include: pre-fetching through envelope optimization, tile display, and feature complexity reduction. These strategies improve the speed and responsiveness with which data can be viewed and analyzed. Comparisons made with other web-based data access implementations are used to evaluate whether these techniques provide performance benefits, and under which circumstances.

关键词： OGC WFS WMS Geographic Information Systems Open Source GIS

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Safety of epinephrine for anaphylaxis in the emergency setting

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World Journal of Emergency Medicine 2013年第4期4卷 245-251页

作者： Joseph p Wood Stephen J Traub christopher Lipinski Department of Emergency Medicine Mayo Clinic HospitalPhoenixAZ 85054USA

BACKGROUND:While epinephrine is the recommended first-line therapy for the reversal of anaphylaxis symptoms,inappropriate use persists because of misunderstandings about proper dosing and administration or misconceptions about its *** objective of this review was to evaluate the safety of epinephrine for patients with anaphylaxis,including other emergent conditions,treated in emergency care ***:A MEDLINE search using pubMed was conducted to identify articles that discuss the dosing,administration,and safety of epinephrine in the emergency setting for anaphylaxis and other ***:Epinephrine is safe for anaphylaxis when given at the correct dose by intramuscular *** majority of dosing errors and cardiovascular adverse reactions occur when epinephrine is given intravenously or incorrectly ***:Epinephrine by intramuscular injection is a safe therapy for anaphylaxis but training may still be necessary in emergency care settings to minimize drug dosing and administration errors and to allay concerns about its safety.

关键词： Allergy Anaphylaxis Epinephrine Safety Cardiovascular side effects

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Timescales of geological processes: preface

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Geoscience Frontiers 2019年第1期10卷 1-3页

作者： Andrew putnis christopher J.Spencer Tom Raimondo The Institute for Geoscience Research School of Earth and Planetary Science Curtin University School of Natural and Built Environments University of South Australia

*** One of the major challenges in Geoscience is to understand how the formation and evolution of the Earth System are governed by timescales-that is,how the various geological processes that continue to contribute to its present-day structure and composition operated in the deep *** traditional view of such processes refers to events that occur at immense spatial scales and over hundreds of millions of years,constrained in most cases by the ages of rocks determined using isotopic dating methods or the fossil ***,the modern view of geological processes has increasingly acknowledged that their durations can be significantly shorter than previously thought possible,or indeed detectable without recent analytical *** are a prime example of rapid,high energy and episodic events that have a profound effect on subsequent processes such as metamorphism,fluid transport,and ore formation e the evidence of which is written in microstructures,compositional zoning,and p-T *** studies have also revealed that the reaction rates between fluids and rocks can be extremely rapid relative to geological *** has led to the notion that geological processes are not necessarily continuous over millions of years but may,in fact,be sporadic,with long periods where essentially no reactions take place punctuated by periods of intense activity.

关键词： In preface Timescales of geological processes

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