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Host-environment mismatches associated with subalpine fir decline in Colorado

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Journal of Forestry Research 2016年第5期27卷 1177-1189页

作者： Robin m. reich John E. Lundquist Kristina Hughes Colorado State University Fort Collins CO USA U.S. Forest Service Anchorage Anchorage AK 99501 USA

Subalpine fir decline （SFD） has killed more trees in Colorado＇s high elevation forests than any other insect or disease problem. The widespread nature of this disorder suggests that the cause involves climatic factors. We examined the influence of varying combinations of average annual temperature and precipitation on the incidence and distribution of SFD. Climatic transition matrices generated in this study indicate that most healthy trees are found in climatic zones with moderate to low temperatures and high precipitation; whereas, SFD occurs mostly in zones of moderate temperatures and moderate precipitation. The contrasting distributions define an environmental mismatch. Forests matched with favorable climatic conditions thrive; those that are mismatched can become vulnerable to decline disease.

关键词： Abiotic disorder Climate stress High elevation forests Forest disease - Subalpine fir

Development of a field enhanced photocatalytic device for biocide of coliform bacteria

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Journal of Environmental Sciences 2016年第6期28卷 38-44页

作者： Jeff m.Huber krista L.Carlson Otakuye Conroy-Ben mano misra Swomitra K.mohanty Departments of Civil Engineering University of Utah Departments of metallurgical Engineering University of Utah Departments of Chemical Engineering University of Utah

A field enhanced flow reactor using bias assisted photocatalysis was developed for bacterial disinfection in lab-synthesized and natural waters. The reactor provided complete inactivation of contaminated waters with flow rates of 50 mL/min. The device consisted of titanium dioxide nanotube arrays, with an externally applied bias of up to 6 V. Light intensity, applied voltage, background electrolytes and bacteria concentration were all found to impact the device performance. Complete inactivation of Escherichia coli W3110（- 8 × 10^3CFU/mL） occurred in 15 sec in the reactor irradiated at 25 mW/cm^2 with an applied voltage of 4 V in a 100 ppm NaCl solution. Real world testing was conducted using source water from Emigration Creek in Salt Lake City, Utah. Disinfection of natural creek water proved more challenging, providing complete bacterial inactivation after 25 sec at 6 V. A reduction in bactericidal efficacy was attributed to the presence of inorganic and organic species, as well as the increase in robustness of natural bacteria.

关键词： Titanium dioxide Nanotubes Immobilized Photocatalysis Escherichia coli Inactivation

A Perfect Storm That Threatens American Democracy

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中国翻译 2011年第6期32卷 71-72页

作者： Robert reich 不详

It＇s a perfect storm. And I＇m not talking about the impending dangers facing Democrats. I＇m talking about the dangers facing our democracy.

关键词：英语学习学习方法英语翻译阅读材料

Uplifting the complexity of analysis for probabilistic security of electricity supply assessments using artificial neural networks

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Energy and AI 2024年第3期17卷 313-326页

作者： Justin münch Jan Priesmann marius reich marius Tillmanns Aaron Praktiknjo mario Adam University of Applied Sciences Duesseldorf Centre of Innovative Energy SystemsMuensterstr.15640476 DuesseldorfGermany RWTH Aachen University E.ON Energy Research CenterChair for Energy System Economics(FCN-ESE)Mathieustrasse 1052074 AachenGermany

The energy sector faces rapid decarbonisation and decision-makers demand reliable assessments of the security of electricity supply. For this, detailed simulation models with a high temporal and technological resolution are required. When confronted with increasing weather-dependent renewable energy generation, probabilistic simulation models have proven. The significant computational costs of calculating a scenario, however, limit the complexity of further analysis. Advances in code optimization as well as the use of computing clusters still lead to runtimes of up to eight hours per scenario. However ongoing research highlights that tailor-made approximations are potentially the key factor in further reducing computing time. Consequently, current research aims to provide a method for the rapid prediction of widely varying scenarios. In this work artificial neural networks (ANN) are trained and compared to approximate the system behavior of the probabilistic simulation model. To do so, information needs to be sampled from the probabilistic simulation in an efficient way. Because only a limited space in the whole design space of the 16 independent variables is of interest, a classification is developed. Finally it required only around 35 min to create the regression models, including sampling the design space, simulating the training data and training the ANNs. The resulting ANNs are able to predict all scenarios within the validity range of the regression model with a coefficient of determination of over 0.9998 for independent test data (1.051.200 data points). They need only a few milliseconds to predict one scenario, enabling in-depth analysis in a brief period of time.

关键词： Security of electricity supply Probabilistic simulation metamodeling Artificial neural networks Regression

Influence of climatic conditions,topography and soil attributes on the spatial distribution of site productivity index of the species rich forests of Jalisco,mexico

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Journal of Forestry Research 2014年第1期25卷 87-95页

作者： Adel mohamed Robin m.reich Raj Khosla C.Aguirre-Bravo martin mendoza Briseo Department of Ecology and Rangeland Stewardship Desert Research Center Department of Forest and Rangeland Stewardship Colorado State University Department of Soil and Crop Sciences Colorado State University USDA Forest Service Colegio de Postgraduados

This paper presents an approach based on field data to model the spatial distribution of the site productivity index （SPI） of the diverse forest types in Jalisco, mexico and the response in SPI to site and cli-matic conditions. A linear regression model was constructed to test the hypothesis that site and climate variables can be used to predict the SPI of the major forest types in Jalisco. SPI varied significantly with topog-raphy （elevation, aspect and slope）, soil attributes （pH, sand and silt）, climate （temperature and precipitation zones） and forest type. The most important variable in the model was forest type, which accounted for 35% of the variability in SPI. Temperature and precipitation accounted for 8 to 9% of the variability in SPI while the soil attributes accounted for less than 4% of the variability observed in SPI. No significant differences were detected between the observed and predicted SPI for the individual forest types. The linear regression model was used to develop maps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity models developed in this study provides a basis for understanding the complex relationship that exists between forest productivity and site and climatic conditions in the state. Findings of this study will assist resource managers in making cost-effective decisions about the management of individual forest types in the state of Jalisco, mexico.

关键词： Best management practices climate change spatial predic-tions tropical dry forests weighted least squares

Occupational injuries and burn out among orthopedic oncology surgeons

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World Journal of Orthopedics 2022年第12期13卷 1056-1063页

作者： Abdulrahman m Alaseem Robert E Turcotte Nathalie Ste-marie mohammad m Alzahrani Saad m Alqahtani krista A Goulding Department of Orthopedic Surgery College of MedicineKing Saud UniversityRiyadh 12372Saudi Arabia Department of Orthopedic Surgery McGill University Health CentreMontreal H4A3J1Canada Department of Orthopedic Surgery College of MedicineImam Abdulrahman Bin Faisal universityDammam 34212Saudi Arabia Department of Orthopaedic Surgery Mayo ClinicPhoenixArizona 85054USA

BACKGROUND Orthopedic oncology surgeons commonly engage in prolonged and complex surgical *** types of surgeries increase the risk of physical and psychological stressors,which may in turn make these physicians prone to workrelated occupational *** The aim of this study was to explore in orthopedic oncologists,the prevalence of work-related physical injuries and psychological *** A modified version of the physical discomfort survey was developed to assess occupational injuries among orthopedic oncology surgeon members of the musculoskeletal Tumor Society,the Canadian Orthopedic Oncology Society and European musculoskeletal Oncology *** survey was sent by email,and it explored musculoskeletal complaints,psychological disturbances,treatment required for these complaints and the requirement of time off *** A total of 67 surgeon responses were collected.A high number of orthopedic oncologists(84%)reported an occupational *** back pain(39%)was the most prevalent musculoskeletal condition,followed by lumbar disk herniation(16%),shoulder tendinitis(15%)and lateral epicondylitis(13%).Of the cohort,46%required surgery and 31%required time off work due to their ***-three respondents reported a psychological ***(27%),anxiety(20%)and insomnia(20%)were the most commonly *** required off work due to injury was associated with old age and years in *** Orthopedic oncology surgeons report a high prevalence of work-related *** back related injury and burnout were the most reported *** operative room ergonomics and prevention of stress related to the work environment should be areas to explore in upcoming research.

关键词： Orthopedic oncology Surgeons Occupational musculoskeletal Injuries

Community phylogenetic diversity and abiotic site characteristics influence abundance of the invasive plant Rhamnus cathartica L.

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Journal of Plant Ecology 2014年第2期7卷 202-209页

作者： Timothy J.S.Whitfeld Alexandra G.Lodge Alexander m.Roth Peter B.reich Department of Forest Resources University of Minnesota1530 Cleveland Avenue NorthSt PaulMN 55108-6112USA Hawkesbury Institute for the Environment University of Western SydneyPenrithNSW 2751Australia

Aims Theory predicts that the success of introduced species is related to the diversity of native species through trait-based *** site characteristics may also affect a site’s susceptibility to *** quantified resident plant species richness,phylogenetic diversity and several abiotic site characteristics for 24 oak forests in minnesota,USA,to assess their impact on the abundance of a widespread,introduced terrestrial plant species,common buckthorn(Rhamnus cathartica L.).Specifically,we asked(1)whether resident species richness and phylogenetic diversity affected the abundance of *** and(2)what site characteristics explained the overall abundance of *** Our survey included 24 oak-dominated stands in minnesota’s deciduous *** each stand,we identified all species in 16 *** also measured a series of environmental site characteristics,including canopy openness(a proxy for light availability),percent bare soil,soil pH,percent sand,an index of propagule availability,duff layer thickness(a proxy for earthworm activity),an index of insolation and *** all species present in at least one site,we estimated a community *** combined all sitelevel characteristics,including phylogenetic diversity of the resident plant species,in a multiple regression model to examine site-level drivers of community *** Findings Results indicate that sites with higher overall plant phylogenetic diversity harbor less ***,even though native species richness was not significantly related to *** *** analyses indicated that,in addition to resident species phylogenetic diversity,the most important predictors of *** abundance were canopy openness and the amount of bare soil,both positively related to the abundance of the *** combining the effects of abiotic site characteristics and resident species phylogenetic diversity in a model that predicted the abundance of R

关键词： invasibility R.cathartica L. phylogenetic diversity site characteristics

Empirical evaluation of confidence and prediction intervals for spatial models of forest structure in Jalisco,mexico

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Journal of Forestry Research 2011年第2期22卷 159-166页

作者： Robin m.reich C.Aguirre-Bravo Vanessa A.Bravo martin mendoza Briseo Department of Forest and Rangeland Stewardship Colorado State UniversityFort CollinsCO 80523-1472 USA USDA Forest Service ArlingtonVA 22209-2131 USA Clegio de Postgraduados Campus MontecillosTexcocoMexico

In recent years there has been an increasing interest in developing spatial statistical models for data sets that are seemingly spatially *** lack of spatial structure makes it difficult,if not impossible to use optimal predictors such as ordinary kriging for modeling the spatial variability in the *** many instances,the data still contain a wealth of information that could be used to gain flexibility and precision in *** this paper we propose using a combination of regression analysis to describe the large-scale spatial variability in a set of survey data and a tree-based stratification design to enhance the estimation process of the small-scale spatial *** this approach,sample units（i.e.,pixel of a satellite image） are classified with respect to predictions of error attributes into homogeneous classes,and the classes are then used as strata in the stratified *** variables used as a basis of stratification included terrain data and satellite imagery.A decision rule was used to identify a tree size that minimized the error in estimating the variance of the mean response and prediction uncertainties at new spatial *** approach was applied to a set of n=937 forested plots from a state-wide inventory conducted in 2006 in the mexican State of *** final models accounted for 62% to 82% of the variability observed in canopy closure（%）,basal area（m2·ha-1）,cubic volumes（m3·ha-1） and biomass（t·ha-1） on the sample *** spatial models provided unbiased estimates and when averaged over all sample units in the population,estimates of forest structure were very close to those obtained using classical estimates based on the sampling strategy used in the state-wide *** spatial models also provided unbiased estimates of model variances leading to confidence and prediction coverage rates close to the 0.95 nominal rate.

关键词： tree-based stratified design generalized least squares standardized mean squared error Landsat-7 ETm+