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Fire and retention island remnants have similar deadwood carbon stock a decade after disturbances in boreal forests of Alberta
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作者 Richard Osei Lance P.Moore +3 位作者 Rosanise A.Odell Marcel Schneider Tanvir Ahmed Shovon Charles A.Nock 《Forest Ecosystems》 SCIE CSCD 2024年第5期677-684,共8页
In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests,ecosystem-based forest management(EBM)has become the de facto management approach.Retention forestry represents one prominen... In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests,ecosystem-based forest management(EBM)has become the de facto management approach.Retention forestry represents one prominent way that EBM is implemented in many parts of the world.Retention patches commonly left after harvesting serve as analogues of fire island remnants,which are patches of unburned forests in the burned forest matrix.Although the persistence of retention patches has been questioned,few studies have attempted to quantitatively compare forest attributes in both burned and harvested forests.As part of a larger program examining multiple aspects of ecosystem function in fire and harvest island remnants,we investigated the impact of disturbance type(fire/harvest)and forest edges on C stock in snags and coarse woody debris(CWD)found in island remnants in mixedwood boreal forests of Alberta,Canada.Total C stock(in snags and CWD)was similar between the two disturbance types and edge plots had similar total deadwood C stocks to interiors.The edges of island remnants had about two-fold more snag C stock than their interiors in both disturbance types,but C stock in CWD was unaffected by edge effects and disturbance type.Our results suggest that deadwood C dynamics in island remnants in fire and harvest disturbed boreal forests were similar,thus lending support for the continued implementation of retention forestry in Alberta. 展开更多
关键词 Retention forestry DEADWOOD Ecosystem-based management WILDFIRES Boreal forest
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Relations Between School and Immigrant Families in Albertan Francophone School: Perspectives of Settlement Workers in Schools - A Secondary Publication
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作者 Marianne Jacquet Gwenaëlle André 《Journal of Contemporary Educational Research》 2024年第3期136-147,共12页
In recent years,Francophone schools in Alberta,a province in western Canada,have seen significant ethnocultural diversification of their school population,thus reflecting recent migratory changes in Canada.The populat... In recent years,Francophone schools in Alberta,a province in western Canada,have seen significant ethnocultural diversification of their school population,thus reflecting recent migratory changes in Canada.The population of a Francophone school board located in an agglomeration of Alberta reflects these new migratory trends.A partial ethnodemographic portrait carried out in 2003 in six of its schools indicates that 50%of the pupils come from an immigrant background and come from 23 different countries;mostly from sub-Saharan African countries.This demographic reality,confirmed more than a decade later,represents a major structural change for Francophone schools.In Alberta,as in other Canadian provinces,inclusion is at the heart of discourse and educational practices.With a transformative aim,it intends to promote ethnocultural diversity in the classroom and equal opportunities through school equity practices.This article focuses on the settlement workers in schools responsible for bridging family,community,and school cultures.The analysis of the interviews of the four workers sheds light on and questions both the institutional practices and the personal strategies put in place to face the challenges encountered in this tripartite collaboration. 展开更多
关键词 Educational inclusion and exclusion Immigration and ethnicity Interculturality and multiculturalism Family and education Help for pupils and students Actors in education Canada
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Sensitivity to Acidification of Forest Soils in Two Watersheds with Contrasting Hydrological Regimes in the Oil Sands Region of Alberta 被引量:1
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作者 Y. S. OK S. X. CHANG Y. S. FENG 《Pedosphere》 SCIE CAS CSCD 2007年第6期747-757,共11页
Input of large amounts of N and S compounds into forest ecosystems through atmospheric deposition is a significant risk for soil acidification in the oil sands region of Alberta.We evaluated the sensitivity of forest ... Input of large amounts of N and S compounds into forest ecosystems through atmospheric deposition is a significant risk for soil acidification in the oil sands region of Alberta.We evaluated the sensitivity of forest soils to acidification in two watersheds(Lake 287 and Lake 185)with contrasting hydrological regimes as a part of a larger project assessing the role of N and S cycling in soil acidification in forest ecosystems.Fifty six forest soil samples were collected from the two watersheds by horizon from 10 monitoring plots dominated by either jack pine(Pinus banksiana)or aspen(Populus tremuloides).Soils in the two watersheds were extremely to moderately acidic with pH(CaCl_2)ranging from 2.83 to 4.91.Soil acid-base chemistry variables such as pH,base saturation,Al saturation,and acid-buffering capacity measured using the acetic acid equilibrium procedure indicated that soils in Lake 287 were more acidified than those in Lake 185. Acid-buffering capacity decreased in the order of forest floor>subsurface mineral soil>surface mineral soil.The most dramatic differences in percent Ca and Al saturations between the two watersheds were found in the surface mineral soil horizon.Percent Ca and Al saturation in the surface mineral soil in Lake 287 were 15% and 70%,respectively;the percent Ca saturation value fell within a critical range proposed in the literature that indicates soil acidification.Our results suggest that the soils in the two watersheds have low acid buffering capacity and would be sensitive to increased acidic deposition in the region. 展开更多
关键词 acid-buffering capacity Al saturation base saturation pH soil acidification
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Morphological characterization of fungi associated with the ascochyta blight complex and pathogenic variability of Mycosphaerella pinodes on field pea crops in central Alberta 被引量:1
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作者 Hafiz Ahmed Kan-Fa Chang +5 位作者 Sheau-Fang Hwang Heting Fu Qixing Zhou Stephen Strelkov Robert Conner Bruce Gossen 《The Crop Journal》 SCIE CAS CSCD 2015年第1期10-18,共9页
Field pea crops in central Alberta were surveyed for ascochyta blight from 2011 to 2012 and fungal isolates were recovered from foliar lesions on selected plants. Cultural and microscopic characterization of the 275 i... Field pea crops in central Alberta were surveyed for ascochyta blight from 2011 to 2012 and fungal isolates were recovered from foliar lesions on selected plants. Cultural and microscopic characterization of the 275 isolates obtained revealed that 272 were of Mycosphaerella pinodes and three were of Phoma medicaginis var. pinodella. Ascochyta pisi or Phoma koolunga were not identified. Isolates of M. pinodes were divided into two groups,GI and GII, based on visual assessment of culture characteristics. GI isolates(light to dark, mostly gray colony color; pycnidial distribution radial and concentric; conidia10.5–14.5 × 4.2–6.2 μm most with one septum, occasionally two, constricted at the septum;spore mass light buff to flesh color) were predominant(83%), while GII isolates(dark to gray colony color; pycnidia abundant; conidia 8–16 × 3.5–6.2 μm most with 1 septum, constricted at the septum; spore mass light buff to flesh color) were less common(17%). The cultures of GII isolates were similar to recent descriptions of A. pisi, but they differed in spore color. In a host differential study, 13 pathotypes of M. pinodes were identified from 110 single-spore isolates. Pathotype I was predominant(88 isolates) and virulent on all nine differential genotypes. The other pathotypes(pathotypes II–XIII) were rare(1–6 isolates of each).Comparison of the present results with earlier studies suggests that pathotype I has been prevalent for many years, and that its aggressiveness on the host differentials has increased over time. Emphasis should be placed on breeding for resistance to M. pinodes in field pea cultivars intended for deployment in central Alberta. 展开更多
关键词 ASCOCHYTA PHOMA Resistance VIRULENCE PATHOTYPE
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Development of a convolutional neural network based geomechanical upscaling technique for heterogeneous geological reservoir 被引量:1
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作者 Zhiwei Ma Xiaoyan Ou Bo Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2111-2125,共15页
Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological developments.However,a robust and e... Geomechanical assessment using coupled reservoir-geomechanical simulation is becoming increasingly important for analyzing the potential geomechanical risks in subsurface geological developments.However,a robust and efficient geomechanical upscaling technique for heterogeneous geological reservoirs is lacking to advance the applications of three-dimensional(3D)reservoir-scale geomechanical simulation considering detailed geological heterogeneities.Here,we develop convolutional neural network(CNN)proxies that reproduce the anisotropic nonlinear geomechanical response caused by lithological heterogeneity,and compute upscaled geomechanical properties from CNN proxies.The CNN proxies are trained using a large dataset of randomly generated spatially correlated sand-shale realizations as inputs and simulation results of their macroscopic geomechanical response as outputs.The trained CNN models can provide the upscaled shear strength(R^(2)>0.949),stress-strain behavior(R^(2)>0.925),and volumetric strain changes(R^(2)>0.958)that highly agree with the numerical simulation results while saving over two orders of magnitude of computational time.This is a major advantage in computing the upscaled geomechanical properties directly from geological realizations without the need to perform local numerical simulations to obtain the geomechanical response.The proposed CNN proxybased upscaling technique has the ability to(1)bridge the gap between the fine-scale geocellular models considering geological uncertainties and computationally efficient geomechanical models used to assess the geomechanical risks of large-scale subsurface development,and(2)improve the efficiency of numerical upscaling techniques that rely on local numerical simulations,leading to significantly increased computational time for uncertainty quantification using numerous geological realizations. 展开更多
关键词 Upscaling Lithological heterogeneity Convolutional neural network(CNN) Anisotropic shear strength Nonlinear stressestrain behavior
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Impact of effective stress on permeability for carbonate fractured-vuggy rocks 被引量:1
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作者 Ke Sun Huiqing Liu +5 位作者 Juliana Y.Leung Jing Wang Yabin Feng Renjie Liu Zhijiang Kang Yun Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期942-960,共19页
To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of ef... To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of effective stress on permeability for carbonate fractured-vuggy rocks(CFVR).It shows that the permeability performance curves under different pore and confining pressures(i.e.altered stress conditions)for the fractured core models and the vuggy core models have similar change patterns.The ranges of permeability variation are significantly wider at high pore pressures,indicating that permeability reduction is the most significant during the early stage of development for fractured-vuggy reservoirs.Since each obtained effective stress coefficient for permeability(ESCP)varies with the changes in confining pressure and pore pressure,the effective stresses for permeability of four representative CFVR show obvious nonlinear characteristics,and the variation ranges of ESCP are all between 0 and 1.Meanwhile,a comprehensive ESCP mathematical model considering triple media,including matrix pores,fractures,and dissolved vugs,was proposed.It is proved theoretically that the ESCP of CFVR generally varies between 0 and 1.Additionally,the regression results showed that the power model ranked highest among the four empirical models mainly applied in stress sensitivity characterization,followed by the logarithmic model,exponential model,and binomial model.The concept of“permeability decline rate”was introduced to better evaluate the stress sensitivity performance for CFVR,in which the one-fracture rock is the strongest,followed by the fracture-vug rock and two-horizontalfracture rock;the through-hole rock is the weakest.In general,this study provides a theoretical basis to guide the design of development and adjustment programs for carbonate fractured-vuggy reservoirs. 展开更多
关键词 Effective stress PERMEABILITY Carbonate fractured-vuggy rocks Structure characteristics Stress sensitivity
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Profiles of energy metabolites and haptoglobin in dairy cows under organic management in Alberta farms
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作者 John F. Odhiambo Umar Farooq +4 位作者 Summera Iqbal Dominik Mansmann Qendrim Zebeli Suzanna M. Dunn Burim N. Ametaj 《Open Journal of Animal Sciences》 2013年第2期105-113,共9页
Profiles of energy metabolites and haptoglobin (Hp) in dairy cows that are transitioned from conventional to organic management in various Alberta farms were compared with those of dairy cows managed conventionally at... Profiles of energy metabolites and haptoglobin (Hp) in dairy cows that are transitioned from conventional to organic management in various Alberta farms were compared with those of dairy cows managed conventionally at the University of Alberta dairy farm. Blood samples were collected during the following periods: Dry, 0 - 30, 30 - 60, and 60 - 90 days in milk (DIM, n = 7 cows). Concentrations of metabolites were evaluated by enzymatic colorimetric methods. Concentrations of Hp were determined by bovine ELISA kits. Data were analyzed by the mixed procedures of SAS. Concentrations of NEFA and BHBA in blood were elevated (P < 0.001) 0 to 30 d, intermediate 30 to 60, and 60 to 90 d, and lower in the dry period. In addition, BHBA was higher (P < 0.0001) at all stages of lactation in conventional than organic cows (e.g. 1289.4 ± 88.6 vs. 883.6 ± 47.5 μmol/L in conventional and organic cows at 0 - 30 d, respectively). Serum concentrations of cholesterol increased with increasing DIM and returned to nadir levels during dry period and was higher (P < 0.0001) in conventional than organic cows. Low glucose concentrations were observed 0 to 30 d, levels were intermediate 30 to 60 and 60 to 90 d, and peaked during the dry period (P < 0.54) between conventional and organic cows. Lactate did not (P < 0.24) vary with DIM or day × farm type but was higher (P < 0.0001) in organic cows than in conventional cows. Serum concentrations of Hp were elevated during dry period;reached peak levels 0 to 30 d and decreased gradually with increasing days postpartum and were much higher at all periods in conventional than organic cows. Overall, concentrations of Hp were 528.1 ± 45.2 μg/mL in conventional cows vs. 261.1 ± 16.9 μg/mL in organic cows (P < 0.0001). Taken together, these data indicate that metabolic changes associated with initiation of lactation are preceded by an acute phase response in dairy cows, and that cows in organic systems seem to be healthier than cows under conventional systems. These differences might be due to differences in nutritional management in the two systems. 展开更多
关键词 ORGANIC COWS BHBA NEFA HAPTOGLOBIN
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“Lifting More” is Associated with Lower Risks of Depression in University Students
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作者 Kang Ai Kimberley Curtin +3 位作者 Kaja Kastelic Cain Clark Si-Tong Chen Xinli Chi 《International Journal of Mental Health Promotion》 2021年第4期471-485,共15页
Research on the population in western world showed that,MSE(muscle-strengthening exercise)is beneficial to the treatment of mental disorders.However,the situation in Chinese adults is little known.For this reason,the ... Research on the population in western world showed that,MSE(muscle-strengthening exercise)is beneficial to the treatment of mental disorders.However,the situation in Chinese adults is little known.For this reason,the study is performed to understand the connection between depression and MSE among college and university students in China aged between 18 to 24.1793 college students have been recruited,and their average age is 20.67.A questionnaire has been developed and it is self-reported and designed to collect information about MSE and participants,including body mass index and sex and so on.Sleep and physical activity have been evaluated by introducing two scales,that is,Pittsburgh Sleep Quality Index and International Physical Activity Questionnaire-Short Form,respectively.Moreover,Patient Health Questionnaire-9 has been adopted to indicate the severity of depression of participants.The link between depression and MSE has been studied by introducing multilevel linear regression.Among all these study participants,just 24.87%of them met the MSE standards of World Health Organization,that is,more than 2 days every week.The average depression score was 6.80(±5.19).Greater num-ber of days for MSE shows negative association with the depression,with (beta=-0.17,95%CI:-0.31 to-0.03,p=0.015).Those students failing to meet MSE standards are more susceptible to the depression risk(beta=0.63,95%CI:0.09–0.19,p=0.027).The results show that,there is a relationship between MSE participation and relieved status of depression among young adults in China.Interventions designed to relieve depression can be developed on the basis of MSE. 展开更多
关键词 College students DEPRESSION mental health muscle strengthening activity
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Targeting gut microbiota in osteoporosis:impact of the microbial based functional food ingredients
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作者 Pauline Duffuler Khushwant S.Bhullar Jianping Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期1-15,共15页
Osteoporosis is the most common bone disorder,characterized by low bone mineral density and microarchitectural deterioration of the bone tissue,which increases the susceptibility to fracture.In the past decade,emergin... Osteoporosis is the most common bone disorder,characterized by low bone mineral density and microarchitectural deterioration of the bone tissue,which increases the susceptibility to fracture.In the past decade,emerging research findings reported the implication of gut microbiota on bone health and osteoporosis pathology.Osteoporotic patients or individuals with a lower bone mineral density exhibit an alteration of the gut microbiota at several taxonomic levels.Additional reports demonstrate that gut microbiota regulates bone metabolism through the modulation of the gut function(mineral availability and absorption,gut integrity),the immune system,and the endocrine system.Thus,based on the vital role of gut microbiota on bone health,it has emerged as a novel therapeutic target for the prevention of bone loss and the treatment of osteoporosis.Microbial-based functional food ingredients,such as probiotics,prebiotics,synbiotics,and fermented foods,have been developed to alter the gut microbiota composition and function and thus,to provide benefits to the host bone health.Despite promising initial results,microbial-based therapies are still under investigation.Moreover,additional animal studies and clinical trials are needed to understand the interactions between gut microbiota and bone metabolism before further applications. 展开更多
关键词 DYSBIOSIS Bone health Probiotic Prebiotic Fermented food SYNBIOTIC
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Oral administration of egg white ovotransferrin prevents osteoporosis in ovariectomized rats
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作者 Nan Shang Xiaoyu Bao +1 位作者 Michael Doschak Jianping Wu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2562-2572,共11页
Ovotransferrin,an iron-binding glycoprotein,accounting for approximately 12%of egg white protein,is a member of transferrin fam ily.Our previous studies showed that ovotransferrin stimulates the proliferation and diff... Ovotransferrin,an iron-binding glycoprotein,accounting for approximately 12%of egg white protein,is a member of transferrin fam ily.Our previous studies showed that ovotransferrin stimulates the proliferation and differentiation of osteoblasts,while inhibits osteoclastogenesis and resorption activity.The work aims to study the efficacy of orally administered ovotransferrin on the prevention of osteoporosis using ovariectomized(OVX)Sprague-Dawley rats.Oral administration of ovotransferrin showed no negative effect on body weight,food intake and organ weight.After 12-week treatment,feeding ovotransferrin at a dose of 1%(1 g ovotransferrin/100 g diet)prevented OVX-induced bone loss and maintained relatively high bone mineral density and integrated bone microarchitecture.The serum concentration of biomarkers indicating bone formation was increased in ovotransferrin administration groups,while the bone resorption biomarkers were decreased.Ovotransferrin feeding also decreased the production of serum cytokine TNF-αand IL-6,which are two stimulators for osteoclast differentiation.In addition to its direct regulatory role on bone turnover,ovotransferrin supplementation might benefit osteoporosis prevention by inhibiting adipogenesis,and regulating immune response.Our results suggested the potential application of ovotransferrin as a functional food ingredient on the prevention of osteoporosis. 展开更多
关键词 OVOTRANSFERRIN Ovariectomized(OVX)rats Bone mineral density Bone microarchitecture Bone resorption INFLAMMATION
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Alternative Method of Constructing Granular Neural Networks
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作者 Yushan Yin Witold Pedrycz Zhiwu Li 《Computers, Materials & Continua》 SCIE EI 2024年第4期623-650,共28页
Utilizing granular computing to enhance artificial neural network architecture, a newtype of network emerges—thegranular neural network (GNN). GNNs offer distinct advantages over their traditional counterparts: The a... Utilizing granular computing to enhance artificial neural network architecture, a newtype of network emerges—thegranular neural network (GNN). GNNs offer distinct advantages over their traditional counterparts: The ability toprocess both numerical and granular data, leading to improved interpretability. This paper proposes a novel designmethod for constructing GNNs, drawing inspiration from existing interval-valued neural networks built uponNNNs. However, unlike the proposed algorithm in this work, which employs interval values or triangular fuzzynumbers for connections, existing methods rely on a pre-defined numerical network. This new method utilizesa uniform distribution of information granularity to granulate connections with unknown parameters, resultingin independent GNN structures. To quantify the granularity output of the network, the product of two commonperformance indices is adopted: The coverage of numerical data and the specificity of information granules.Optimizing this combined performance index helps determine the optimal parameters for the network. Finally,the paper presents the complete model construction and validates its feasibility through experiments on datasetsfrom the UCIMachine Learning Repository. The results demonstrate the proposed algorithm’s effectiveness andpromising performance. 展开更多
关键词 Granular neural network granular connection interval analysis triangular fuzzy numbers particle swarm optimization(PSO)
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Upper and Lower Bounds of the α-Universal Triple I Method for Unified Interval Implications
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作者 Yiming Tang Jianwei Gao Yifan Huang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1063-1088,共26页
Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning al... Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning algorithms to a large extent,which is quantified by calculating the disparity between the output of fuzzy reasoning with interference and the output without interference.Therefore,in this study,the interval robustness(embodied as the interval stability)of theα-UTI method is explored in the interval-valued fuzzy environment.To begin with,the stability of theα-UTI method is explored for the case of an individual rule,and the upper and lower bounds of its results are estimated,using four kinds of unified interval implications(including the R-interval implication,the S-interval implication,the QL-interval implication and the interval t-norm implication).Through analysis,it is found that theα-UTI method exhibits good interval stability for an individual rule.Moreover,the stability of theα-UTI method is revealed in the case of multiple rules,and the upper and lower bounds of its outcomes are estimated.The results show that theα-UTI method is stable for multiple rules when four kinds of unified interval implications are used,respectively.Lastly,theα-UTI reasoning chain method is presented,which contains a chain structure with multiple layers.The corresponding solutions and their interval perturbations are investigated.It is found that theα-UTI reasoning chain method is stable in the case of chain reasoning.Two application examples in affective computing are given to verify the stability of theα-UTImethod.In summary,through theoretical proof and example verification,it is found that theα-UTImethod has good interval robustness with four kinds of unified interval implications aiming at the situations of an individual rule,multi-rule and reasoning chain. 展开更多
关键词 Fuzzy reasoning the CRI method the triple I method fuzzy implication interval robustness
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Evaluation of soil erosion vulnerability in Hubei Province of China using RUSLE model and combination weighting method
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作者 YANG Yanpan TIAN Pei +3 位作者 JIA Tinghui WANG Fei YANG Yang HUANG Jianwu 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3318-3336,共19页
Soil erosion has been recognized as a critical environmental issue worldwide.While previous studies have primarily focused on watershed-scale soil erosion vulnerability from a natural factor perspective,there is a not... Soil erosion has been recognized as a critical environmental issue worldwide.While previous studies have primarily focused on watershed-scale soil erosion vulnerability from a natural factor perspective,there is a notable gap in understanding the intricate interplay between natural and socio-economic factors,especially in the context of spatial heterogeneity and nonlinear impacts of human-land interactions.To address this,our study evaluates the soil erosion vulnerability at a provincial scale,taking Hubei Province as a case study to explore the combined effects of natural and socio-economic factors.We developed an evaluation index system based on 15 indicators of soil erosion vulnerability:exposure,sensitivity,and adaptability.In addition,the combination weighting method was applied to determine index weights,and the spatial interaction was analyzed using spatial autocorrelation,geographical temporally weighted regression and geographical detector.The results showed an overall decreasing soil erosion intensity in Hubei Province during 2000 and 2020.The soil erosion vulnerability increased before 2000 and then.The areas with high soil erosion vulnerability were mainly confined in the central and southern regions of Hubei Province(Xiantao,Tianmen,Qianjiang and Ezhou)with obvious spatial aggregation that intensified over time.Natural factors(habitat quality index)had negative impacts on soil erosion vulnerability,whereas socio-economic factors(population density)showed substantial spatial variability in their influences.There was a positive correlation between soil erosion vulnerability and erosion intensity,with the correlation coefficients ranging from-0.41 and 0.93.The increase of slope was found to enhance the positive correlation between soil erosion vulnerability and intensity. 展开更多
关键词 Soil erosion vulnerability RUSLE model Combination weighting method Driving factors Spatial heterogeneity
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The emerging role of exercise as a cancer treatment
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作者 Kerry S.Courneya 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期443-444,共2页
Over the past few decades,exercise oncology has emerged as an important subfield within exercise science.Over that time,substantial progress has been made in understanding the role of exercise in people newly diagnose... Over the past few decades,exercise oncology has emerged as an important subfield within exercise science.Over that time,substantial progress has been made in understanding the role of exercise in people newly diagnosed with cancer,actively being treated for cancer,and recovering after cancer treatments. 展开更多
关键词 CANCER TREATMENT EXERCISE
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Facilitated Prediction of Micropollutant Degradation via UV-AOPs in Various Waters by Combining Model Simulation and Portable Measurement
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作者 Yanyan Huang Mengkai Li +3 位作者 Zhe Sun Wentao Li James R.Bolton Zhimin Qiang 《Engineering》 SCIE EI CAS CSCD 2024年第6期87-95,共9页
The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water matrix.Various reactive radicals(RRs)formed in UV-AOPs have different reaction... The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water matrix.Various reactive radicals(RRs)formed in UV-AOPs have different reaction selectivities toward water matrices and degradation efficiencies for target micropollutants.Hence,process selection and optimization are crucial.This study developed a facilitated prediction method for the photon fluence-based rate constant for micropollutant degradation(K′_(p,MP))in various UV-AOPs by combining model simulation with portable measurement.Portable methods for measuring the scavenging capacities of the principal RRs(RRSCs)involved in UV-AOPs(i.e.,HO^(·),SO_(4)^(·-),and Cl^(·))using a mini-fluidic photoreaction system were proposed.The simulation models consisted of photochemical,quantitative structure–activity relationship,and radical concentration steady-state approximation models.The RRSCs were determined in eight test waters,and a higher RRSC was found to be associated with a more complex water matrix.Then,by taking sulfamethazine,caffeine,and carbamazepine as model micropollutants,the k′_(p,MP) values in various UV-AOPs were predicted and further verified experimentally.A lower k′_(p,MP) was found to be associated with a higher RRSC for a stronger RR competition;for example,k′_(p,MP) values of 130.9 and 332.5 m^(2) einstein^(–1),respectively,were obtained for carbamazepine degradation by UV/H_(2)O_(2) in the raw water(RRSC=9.47×10^(4) s^(-1))and sand-filtered effluent(RRSC=2.87×10^(4) s^(-1))of a drinking water treatment plant.The developed method facilitates process selection and optimization for UV-AOPs,which is essential for increasing the efficiency and cost-effectiveness of water treatment. 展开更多
关键词 UV-AOPs Micropollutant degradation Reactive radicals Water matrix Model simulation
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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability
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作者 Ming-Wei Zhao Zhen-Feng Ma +5 位作者 Cai-Li Dai WeiWu Yong-Quan Sun Xu-Guang Song Yun-Long Cheng Xiang-Yu Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1113-1121,共9页
Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performa... Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications. 展开更多
关键词 Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance
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Routine utilization of machine perfusion in liver transplantation:Ready for prime time?
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作者 Alessandro Parente Keyue Sun +2 位作者 Philipp Dutkowski AM James Shapiro Andrea Schlegel 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1488-1493,共6页
The last decade has been notable for increasing high-quality research and dramatic improvement in outcomes with dynamic liver preservation.Robust evidence from numerous randomized controlled trials has been pooled by ... The last decade has been notable for increasing high-quality research and dramatic improvement in outcomes with dynamic liver preservation.Robust evidence from numerous randomized controlled trials has been pooled by meta-analyses,providing the highest available evidence on the protective effect of machine perfusion(MP)over static cold storage in liver transplantation(LT).Based on a protective effect with less complications and improved graft survival,the field has seen a paradigm shift in organ preservation.This editorial focuses on the role of MP in LT and how it could become the new“gold standard”.Strong collaborative efforts are needed to explore its effects on long-term outcomes. 展开更多
关键词 Liver transplantation Machine perfusion Viability assessment Hypothermic oxygenated perfusion Normothermic machine perfusion
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Exploring impacts of COVID-19 on spatial and temporal patterns of visitors to Canadian Rocky Mountain National Parks from social media big data
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作者 Dehui Christina Geng Amy Li +4 位作者 Jieyu Zhang Howie W.Harshaw Christopher Gaston Wanli Wu Guangyu Wang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期13-33,共21页
COVID-19 posed challenges for global tourism management.Changes in visitor temporal and spatial patterns and their associated determinants pre-and peri-pandemic in Canadian Rocky Mountain National Parks are analyzed.D... COVID-19 posed challenges for global tourism management.Changes in visitor temporal and spatial patterns and their associated determinants pre-and peri-pandemic in Canadian Rocky Mountain National Parks are analyzed.Data was collected through social media programming and analyzed using spatiotemporal analysis and a geographically weighted regression(GWR)model.Results highlight that COVID-19 significantly changed park visitation patterns.Visitors tended to explore more remote areas peri-pandemic.The GWR model also indicated distance to nearby trails was a significant influence on visitor density.Our results indicate that the pandemic influenced tourism temporal and spatial imbalance.This research presents a novel approach using combined social media big data which can be extended to the field of tourism management,and has important implications to manage visitor patterns and to allocate resources efficiently to satisfy multiple objectives of park management. 展开更多
关键词 Tourism management Social media big data National parks COVID-19 Geographical weighted regression
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Effect of simulated gastrointestinal digestion on antioxidant,and anti-inflammatory activities of bioactive peptides generated in sausages fermented with Staphylococcus simulans QB7
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作者 Hongying Li Hongbing Fan +2 位作者 Zihan Wang Qiujin Zhu Jianping Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1662-1671,共10页
Dry-fermented sausages are a good source of bioactive peptides,whose stability against gastrointestinal(GI)digestion determines their bioaccessibility.This study focused on evaluating the effect of peptide extracts fr... Dry-fermented sausages are a good source of bioactive peptides,whose stability against gastrointestinal(GI)digestion determines their bioaccessibility.This study focused on evaluating the effect of peptide extracts from sausages fermented with Staphylococcus simulans QB7 during in vitro simulated GI digestion,including peptide profiles and antioxidant and anti-inflammatory activities.Peptides present in sausages were degraded during digestion,with molecular weight reduced from>12 kDa to<1.5 kDa.Besides,the content of amino acids increased from 381.15 to 527.07 mg/g,especially tyrosine being found only after GI digestion.The anti-inflammatory activities were increased after GI digestion,however,the changes in antioxidant activities were the opposite.A total number of 255,252 and 386 peptide sequences were identified in undigested,peptic-digested and GI-digested samples,respectively.PeptideRanker,BIOPEP-UWM and admetSAR were used to further predict the functional properties and intestinal absorption of the identified peptide sequences from GI digestion.Finally,18 peptides were discovered to possess either antioxidant or anti-inflammatory capacities. 展开更多
关键词 Gastrointestinal digestion SAUSAGES BIOACCESSIBILITY Anti-inflammatory activities
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Exploring the mechanisms of calcium carbonate deposition on various substrates with implications for effective anti-scaling material selection
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作者 Lu Gong Fei-Yi Wu +4 位作者 Ming-Fei Pan Jun Huang Hao Zhang Jing-Li Luo Hong-Bo Zeng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2870-2880,共11页
The unexpected scaling phenomena have resulted in significant damages to the oil and gas industries,leading to issues such as heat exchanger failures and pipeline clogging.It is of practical and fundamental importance... The unexpected scaling phenomena have resulted in significant damages to the oil and gas industries,leading to issues such as heat exchanger failures and pipeline clogging.It is of practical and fundamental importance to understand the scaling mechanisms and develop efficient anti-scaling strategies.However,the underlying surface interaction mechanisms of scalants(e.g.,calcite)with various substrates are still not fully understood.In this work,the colloidal probe atomic force microscopy(AFM)technique has been applied to directly quantify the surface forces between calcite particles and different metallic substrates,including carbon steel(CR1018),low alloy steel(4140),stainless steel(SS304)and tungsten carbide,under different water chemistries(i.e.,salinity and pH).Measured force profiles revealed that the attractive van der Waals(VDW)interaction contributed to the attachment of the calcium carbonate particles on substrate surfaces,while the repulsive electric double layer(EDL)interactions could inhibit the attachment behaviors.High salinity and acidic p H conditions of aqueous solutions could weaken the EDL repulsion and promote the attachment behavior.The adhesion of calcite particles with CR1018 and4140 substrates was much stronger than that with SS304 and tungsten carbide substrates.The bulk scaling tests in aqueous solutions from an industrial oil production process showed that much more severe scaling behaviors of calcite was detected on CR1018 and 4140 than those on SS304 and tungsten carbide,which agreed with surface force measurement results.Besides,high salinity and acidic p H can significantly enhance the scaling phenomena.This work provides fundamental insights into the scaling mechanisms of calcite at the nanoscale with practical implications for the selection of suitable antiscaling materials in petroleum industries. 展开更多
关键词 Scaling phenomenon Metallic substrates Surface forces Bulk scaling tests
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