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Forest Management Plans in Los Planes de La Palma, El Salvador

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Natural Resources 2015年第11期6卷 527-533页

作者： Gisselle A. Mejia blair orr School of Forest Resources and Environmental Science Michigan Technological University Houghton MI USA

Fourteen farmers with small woodlots were interviewed about the forest management plans promoted by the government of El Salvador. As expected, farmers managed for many utilitarian products such as firewood and timber, but the farmers also expressed a strong set of environmental concerns revolved around the ecological value of their woodlots. Farmers generally approved of forest management plans as they saw how plans contributed to sustainable forestry on their woodlots. Farmers had concerns about specific silvicultural practices and about transportation of harvested timber.

关键词： Woodlots Ecotourism Forest Law Chalatenango Sustainable Management

Soil moisture, field-scale toposequential position, and slope effects on yields in irrigated rice (<i>Oryza sativa</i>L.) fields in Honduras

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Agricultural Sciences 2013年第8期4卷 1-8页

作者： Kyle M. Earnshaw blair orr Department of Forestry and Natural Resources Purdue University West Lafayette USA School of Forest Resources and Environmental Science Michigan Technological University Houghton USA

Rice (Oryza sativa L.) is an important cash crop in Honduras. The availability of inexpensive irrigation in the study area (Flores, La Villa de San Antonio, Comayagua) encourages rice farmers to neglect prescribed methods of soil and water conservation, such land leveling, puddling, and soil bunds. This study looked at the effect of failure to mitigate water loss on sloping fields. Soil moisture (Volumetric Water Content) was measured using a soil moisture probe after the termination of the first irrigation within the tillering/vegetative, panicle emergence/flowering, post-flowering/pre-maturation and maturation stages. Yield data were obtained by harvesting on 1 m2 plots in each soil moisture testing site. Data analyses looked at the relationship between yield and slope, soil moisture, farmers, and toposequential position along transects. Toposequential position influenced yields more than slope and soil moisture was not a significant predictor of yields. Irrigation politics, high water inputs, and land tenure were proposed as the major reasons for this result.

关键词： Land Tenure Prices Comayagua Soil Bunds Precipitation

Small-Scale Spatial Patterns of <i>Copernicia alba</i>Morong near Bahia Negra, Paraguay

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Natural Resources 2013年第5期4卷 369-377页

作者： Michelle E. Cisz Michael J. Falkowski blair orr School of Forest Resources and Environmental Science Michigan Technological University Houghton USA

We assessed the spatial distribution of Copernicia alba Morong. In the study area, a lowland palm savanna floodplain, C. alba is the only overstory species. We hypothesized C. alba would be randomly distributed within natural stands. Palms were tallied in six randomly located 0.25 haplots and analyzed using a first-order, Ripley’s K function to assess the distribution of juvenile, adult, and total palm populations. While the total population had either aggregated or random distributions, when analyzing juvenile and adult population separately, we found juveniles were consistently more aggregated than the adults.

关键词： Ripley’s K-Function First Order Analysis Floodplain Fire Chaco Monotypic Stands Disturbance Ecol-ogy Population Dynamics

Potential of photodynamic therapy in the management of infectious oral diseases

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World Journal of Experimental Medicine 2024年第1期14卷 1-5页

作者： Cinzia Casu Germano orrù Department of Surgical Science Oral Biotechnology LaboratoryUniversity of CagliariCagliari 09124Italy

Photodynamic therapy(PDT)can take place in the presence of three elements:Light with an appropriate wavelength;a photosensitizer;and the presence of *** type of treatment is very effective overall against bacterial,viral and mycotic *** the last 10 years many papers have been published on PDT with different types of photosensitizers(e.g.,methylene blue,toluidine blue,indocyanine green,curcumin-based photosensitizers),different wavelengths(e.g.,460 nm,630 nm,660 nm,810 nm)and various parameters(e.g.,power of the light,time of illumination,number of sessions).In the scientific literature all types of PDT seem very effective,even if it is difficult to find a standard protocol for each oral *** could be an interesting way to treat some dangerous oral infections refractory to common pharmacological therapies,such as candidiasis from multidrug-resistant Candida spp.

关键词： Photodynamic therapy oral infections Photodynamic therapy vs candidiasis Blue light 460 nm Streptococcus mutans

The effects of fluid loss on physical performance： A critical review

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Journal of Sport and Health Science 2015年第4期4卷 357-363页

作者： Andrew Carlton Robin Marc orr Faculty of Health Sciences and Medicine Bond Institute of Health and Sport Gold Coast Queensland 4226 Australia

Purpose： The purpose of this review was to critically analyse the cun;ent evidence investigating the effect of an athlete＇s hydration status on physical performance. Methods： A literature search of multiple databases was used to identify studies that met the inclusion criteria for this review. The included studies were then critically appraised using the Downs and Black protocol. Results： Nine articles were found to meet the inclusion criteria, with an average score of 79% for methodological quality representative of a ＂high＂ standard of research. Conclusion： The evidence suggests that dehydration has a negative impact on physical performance for activities lasting more than 30 s in duration. However dehydration was found to have no significant impact on physical performance for activities lasting less than 15 s in duration.

关键词： Athlete Dehydration Euhydration Hydration Performance

Application of first order rate kinetics to explain changes in bloom toxicity——the importance of understanding cell toxin quotas

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Journal of Oceanology and Limnology 2018年第4期36卷 1063-1074页

作者： Philip T.orr Anusuya WILLIS Michele A.BURFORD Australian Rivers Institute Griffith University

Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understanding the mechanisms that drive these changes remains largely a mystery. Changes in bloom toxicity may result from changes in intracellular toxin pool sizes of cyanotoxins with differing molecular toxicities, and/or from changes in the cell concentrations of toxic and non-toxic cyanobacterial species or strains within bloom populations. We show here how first-order rate kinetics at the cellular level can be used to explain how environmental conditions drive changes in bloom toxicity at the ecological level. First order rate constants can be calculated for changes in cell concentration( μ_c : specific cell division rate) or the volumetric biomass concentration( μ_g : specific growth rate) between short time intervals throughout the cell cycle. Similar first order rate constants can be calculated for changes in nett volumetric cyanotoxin concentration( μ_(tox) : specific cyanotoxin production rate) over similar time intervals. How μ_c(or μ_g) covaries with μ tox over the cell cycle shows conclusively when cyanotoxins are being produced and metabolised, and how the toxicity of cells change in response to environment stressors. When μ_(tox)/μ_c >1, cyanotoxin cell quotas increase and individual cells become more toxic because the nett cyanotoxin production rate is higher than the cell division rate. When μ_(tox)/μ_c =1, cell cyanotoxin quotas remains fixed because the nett cyanotoxin production rate matches the cell division rate. When μ_(tox)/μ_c <1, the cyanotoxin cell quota decreases because either the nett cyanotoxin production rate is lower than the cell division rate, or metabolic breakdown and/or secretion of cyanotoxins is occurring. These fundamental equations describe cyanotoxin metabolism dynamics at the cellular level and provide the necessary phys

关键词： cyanotoxin production dynamics first order rate kinetics cyanobacteria

Interactions of primary insult biomechanics and secondary cascades in spinal cord injury： implications for therapy

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Neural Regeneration Research 2017年第10期12卷 1618-1619页

作者： Michael B.orr John C.Gensel Spinal Cord and Brain Injury Research Center and the Department of Physiology the University of KentuckyLexingtonKYUSA Integrated Biomedical Sciences Graduate Program the University of KentuckyLexingtonKYUSA

The complex and variable nature of traumatic spinal cord inju- ry （SCI） presents a unique challenge for translational research. SCI is not bound by any demographic nor is it limited to specific injury biomechanics.

关键词： SCI Interactions of primary insult biomechanics and secondary cascades in spinal cord injury:implications for therapy

Cyanobacteria and cyanotoxins:responses and detection

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Journal of Oceanology and Limnology 2018年第4期36卷 1029-1031页

作者： LI Renhui SONG Lirong Philip T.orr Key Laboratory of Algal Biology State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072China Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Australian Rivers Institute Griffith University170 Kessels RdNathanQld 4111Australia

The 10^(th) International Conference on toxic cyanobacteria(ICTC-10)was successfully held during 23–28 *** were so glad to see much progress made on toxic cyanobacteria and cyanotoxins during past years,and the ICTC does provide a global forum for a wide-ranging communication and discussion of key issues related to cyanobacterial blooms and cyanotoxins.

关键词：蓝毒素细菌海洋生物化学分析

Social interactions in striped hyena inferred from camera trap data:is it more social than previously thought?

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Current Zoology 2020年第4期66卷 345-353页

作者： Jonathan TICHON Jason S.GILCHRIST Guy ROTEM Paul Ward orr Spiegel Mitrani Department of Desert Ecology Ben-Gurion University of the NegevMidreshet Ben-Gurion 84990Israel School of Applied Sciences Edinburgh Napier University1 Sighthll CourtEdinburgh EH114BNUK Spatial Ecology Laboratory Department of Life SciencesBen-Gurion University of the NegevBeer ShebaIsrael Faculty of Lifle Sciences School of ZoologyTel Aviv UniversiyTel Aviv 69978Israel

Understanding the drivers promoting sociality over solitariness in animal species is imperative for predicting future population trends and informing conservation and *** this study we investigate the social structure of a desert dwelling population of striped hyena Hyaena *** species is historically regarded as strictly solitary albeit being the least studied of the extant *** evidence regarding the frequency of social interactions sug-gests a revision of striped hyena social structure is *** hypothesized that striped hyena has a social structure that is more complex than expected for a strictly solitary *** that end,we deployed an array of camera-traps in a remote desert region in Israel,and compared observed frequencies of striped hyena co-occurrence against null models to test whether hyena co-occurred more than expected by *** adults were(re)captured by our camera-traps in 49 different instances over 83 tracking *** these,6 exhibited shared space-use around a scarce,isolated perennial water *** of them,co-occurred with other hyena(in 3 instan-ces)significantly more frequent than expected by chance(and that timing suggests reproduction is unlikely to be the driving factor).Our findings substantiate evidence of complex social structure in striped hyena,highlight the importance of a scarce resource in space use and sociality,and provide a baseline for future research of striped hyena social *** suggest that similar methods be employed to evaluate social structure in other"solitary species"to better under-stand their social dynamics.

关键词： behavioral ecology cluster in space Hyaena hyaena social iteracin striped hyena social structure