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A brief history of neuroscience at the University of British Columbia
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作者 Max S Cynader Heather Amos 《Journal of Translational Neuroscience》 2016年第1期56-59,共4页
Over the past few decades, the field of neuroscience has grown dramatically and made tremendous progress. From its origins in physics, philosophy and psychology, the field has grown to include among its practitioners ... Over the past few decades, the field of neuroscience has grown dramatically and made tremendous progress. From its origins in physics, philosophy and psychology, the field has grown to include among its practitioners talented individuals not only from these founding disciplines but from many others. Though our progress in Neuroscience has been immense, there is still much to be done, and it has become clear that a large number of overlapping complimentary skill sets are required to make progress on the challenging problems that lie ahead. 展开更多
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Differing profiles of people diagnosed with acute and chronic hepatitis B virus infection in British Columbia,Canada 被引量:3
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作者 Mawuena Binka Zahid A Butt +13 位作者 Stanley Wong Mei Chong Jane A Buxton Nuria Chapinal Amanda Yu Maria Alvarez Maryam Darvishian Jason Wong Gina McGowan Mikhail Torban Mark Gilbert Mark Tyndall Mel Krajden Naveed Z Janjua 《World Journal of Gastroenterology》 SCIE CAS 2018年第11期1216-1227,共12页
AIM To describe the characteristics of people diagnosed with acute and chronic hepatitis B virus(HBV) infection in British Columbia(BC).METHODS We used data from the BC Hepatitis Testers Cohort(BCHTC),which includes a... AIM To describe the characteristics of people diagnosed with acute and chronic hepatitis B virus(HBV) infection in British Columbia(BC).METHODS We used data from the BC Hepatitis Testers Cohort(BCHTC),which includes all individuals tested for hepatitis C virus(HCV) or human immunodeficiency virus(HIV) or those diagnosed with HBV or active tuberculosis in BC since 1990.These data were integrated with prescription drug,medical visit,hospitalization and mortality data.HBV cases were classified as acute or chronic according to provincial guidelines.We compared characteristics of individuals by HBV infection group(acute,chronic and negative).Factors associated with acute or chronic HBV infection were assessed with multinomial logistic regression models in comparison to the HBV negative group.RESULTS46498 of the 1058056 eligible BC-HTC participants were diagnosed with HBV infection.4.3% of HBV positive individuals were diagnosed with acute HBV infections while 95.7% had chronic infections.Problematic alcohol use,injection drug use,and HIV or HCV co-infection were more common among individuals diagnosed with acute HBV compared to those with chronic infections and HBV negative individuals.In multivariable multinomial logistic regression models,we observed significant associations between acute or chronic HBV diagnosis and being male,age at HBV diagnosis or birth cohort,South and East Asian ethnicity,HCV or HIV infection,and injection drug use.The odds of acute HBV decreased with increasing age among people who inject drugs,while the opposite was true for chronic HBV.Persons with acute HBV were predominantly White(78%) while those with chronic HBV were mostly East Asian(60%).Relative to Whites,East Asians had 12 times greater odds of being diagnosed with chronic HBV infection.These odds increased with increasing socioeconomic deprivation.CONCLUSION Differences in the profiles of people diagnosed with acute and chronic HBV infection necessitate differentiated screening,prevention,care and treatment programs. 展开更多
关键词 HEPATITIS B virus ETHNICITY Drug use ACUTE HEPATITIS B BC HEPATITIS Testers COHORT North America
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Mental health-related healthcare service utilisation and psychotropic drug dispensation trends in British Columbia during COVID-19 pandemic:a population-based study
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作者 Moe Zandy Sylvia El Kurdi +3 位作者 Hasina Samji Geoff McKee Reka Gustafson Kate Smolina 《General Psychiatry》 CAS CSCD 2023年第1期50-57,共8页
Background The impact of the COVID-19 pandemic on the population’s mental health is vital for informing public health policy and decision-making.However,information on mental health-related healthcare service utilisa... Background The impact of the COVID-19 pandemic on the population’s mental health is vital for informing public health policy and decision-making.However,information on mental health-related healthcare service utilisation trends beyond the first year of the pandemic is limited.Aims We examined mental health-related healthcare service utilisation patterns and psychotropic drug dispensations in British Columbia,Canada,during the COVID-19 pandemic compared with the prepandemic period.Methods We conducted a retrospective population-based secondary analysis using administrative health data to capture outpatient physician visits,emergency department visits,hospital admissions and psychotropic drug dispensations.We examined time trends of mental health-related healthcare service utilisation and psychotropic drug dispensations between January to December 2019(prepandemic period)and January 2020 to December 2021(pandemic period).In addition,we calculated age-standardised rates and rate ratios to compare mental health-related healthcare service utilisation before and during the first two years of the COVID-19 pandemic,stratified by year,sex,age and condition.Results By late 2020,except for emergency department visits,utilisation of healthcare services recovered to prepandemic levels.Between 2019 and 2021,the monthly average rate for overall mental health-related outpatient physician visits,emergency department visits and psychotropic drug dispensations increased significantly by 24%,5%and 8%,respectively.Notable and statistically significant increases were observed among 10–14 year-olds(44%in outpatient physician visits,30%in emergency department visits,55%in hospital admissions and 35%in psychotropic drug dispensations)and 15–19 year-olds(45%in outpatient physician visits,14%in emergency department visits,18%in hospital admissions and 34%in psychotropic drug dispensations).Additionally,these increases were more prominent among females than males,with some variation for specific mental health-related conditions.Conclusions The increase in mental health-related healthcare service utilisation and psychotropic drug dispensations during the pandemic likely reflects significant societal consequences of both the pandemic and pandemic management measures.Recovery efforts in British Columbia should consider these findings,especially among the most affected subpopulations,such as adolescents. 展开更多
关键词 service consequences CANADA
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Comparison of carbon-stock changes, eddycovariance carbon fluxes and model estimates in coastal Douglas-fir stands in British Columbia 被引量:1
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作者 Colin J Ferster JA (Tony) Trofymow +2 位作者 Nicholas C Coops Baozhang Chen Thomas Andrew Black 《Forest Ecosystems》 SCIE CAS CSCD 2015年第2期104-122,共19页
Background: The global network of eddy-covariance (EC) flux-towers has improved the understanding of the terrestrial carbon (C) cycle, however, the network has a relatively limited spatial extent compared to fore... Background: The global network of eddy-covariance (EC) flux-towers has improved the understanding of the terrestrial carbon (C) cycle, however, the network has a relatively limited spatial extent compared to forest inventory data and plots. Developing methods to use inventory-based and EC flux measurements together with modeling approaches is necessary evaluate forest C dynamics across broad spatial extents. Methods: Changes in C stock change (AC) were computed based on repeated measurements of forest inventory plots and compared with separate measurements of cumulative net ecosystem productivity (~NEP) over four years (2003 - 2006) for Douglas-fir (Pseudotsuga menzies# var menziesil} dominated regeneration (HDF00), juvenile (HDF88 and HDF90) and near-rotation (DF49) aged stands (6, 18, 20, 57 years old in 2006, respectively) in coastal British Columbia. AC was determined from forest inventory plot data alone, and in a hybrid approach using inventory data along with litter fall data and published decay equations to determine the change in detrital pools. These AC-based estimates were then compared with Y_NEP measured at an eddy-covariance flux-tower (EC-flux) and modelled by the Carbon Budget Model - Canadian Forest Sector (CBM-CFS3) using historic forest inventory and forest disturbance data. Footprint analysis was used with remote sensing, soils and topography data to evaluate how well the inventory plots represented the range of stand conditions within the area of the flux-tower footprint and to spatially scale the plot data to the area of the EC-flux and model based estimates, Results: The closest convergence among methods was for the juvenile stands while the largest divergences were for the regenerating clearcut, followed by the near-rotation stand. At the regenerating clearcut, footprint weighting of CBM-CFS3 TNEP increased convergence with EC flux Z_NEP, but not for AC. While spatial scaling and footprint weighting did not increase convergence for AC, they did provide confidence that the sample plots represented site conditions as measured by the EC tower. Conclusions: Methods to use inventory and EC flux measurements together with modeling approaches are necessary to understand forest C dynamics across broad spatial extents. Each approach has advantages and limitations that need to be considered for investigations at varying spatial and temporal scales. 展开更多
关键词 Forest carbon MICROMETEOROLOGY Blometry Remote sensing Geographic information systems
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Autoimmune liver disease and the Canadian First Nations Aboriginal Communities of British Columbia's Pacific Northwest 被引量:1
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作者 Eric M Yoshida Mark Riley Laura T Arbour 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第23期3625-3627,共3页
Primary biliary cirrhosis (PBC) is a well-known but uncommon chronic liver disease that is presumed to be of autoimmune etiology. Recently, investigations in British Columbia (BC), a province of Canada situated along ... Primary biliary cirrhosis (PBC) is a well-known but uncommon chronic liver disease that is presumed to be of autoimmune etiology. Recently, investigations in British Columbia (BC), a province of Canada situated along the Pacific North-West of North America, have suggested that PBC is not a rare disease amongst BC's Aboriginal (i.e. First Nations) communities. Geographically, BC is adjacent to South East Alaska, an American state that has also reported an increased prevalence of PBC amongst its Aboriginal communities. In this article, the medical evidence supporting a hypothesis of increased risk of PBC amongst BC's First Nations communities is reviewed. Evidence suggesting that autoimmune hepatitis is also more likely amongst BC's First Nations communities is also presented. 展开更多
关键词 Primary biliary cirrhosis ABORIGINAL FirstNations British Columbia
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Analysis of Impervious Surface Area, and the Impacts on Soil-Based Agriculture and the Hydrologic Cycle: A Case Study in the Agricultural Land Reserve in Metro Vancouver, British Columbia, Canada 被引量:1
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作者 Ashley Rose Julie E. Wilson Les M. Lavkulich 《Agricultural Sciences》 2017年第8期837-856,共20页
The province of British Columbia, Canada, has established an Agricultural Land Reserve (ALR) to protect the most suitable soil landscapes for agriculture. Increases in population and urbanization have resulted in deve... The province of British Columbia, Canada, has established an Agricultural Land Reserve (ALR) to protect the most suitable soil landscapes for agriculture. Increases in population and urbanization have resulted in development challenges on ALR lands. The Metro Vancouver area is the most productive agricultural area in British Columbia as well as the most rapidly growing urban region. The increase in impervious areas has decreased the amount of arable land for soil-based agriculture and altered the hydrological cycle. Analysis using a combination of aerial imagery and GIS found that impervious areas comprise about 10 percent of the ALR within Metro Vancouver. Farm residences and greenhouses have the largest effect on reducing the soil surface for water infiltration. This decrease in area has negatively influenced the ecosystem heath of the region, as well as, decreasing the amount of agricultural land for soil based agriculture and both surface and groundwater dynamics. 展开更多
关键词 AGRICULTURAL Land Reserve Impervious Surfaces Watershed Health STORMWATER Runoff HYDROLOGY
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Drivers of spatial structure in thinned forests
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作者 Zichun Wang Yaoxiang Li +4 位作者 Guangyu Wang Zheyu Zhang Ya Chen Xiaoli Liu Rundong Peng 《Forest Ecosystems》 SCIE CSCD 2024年第2期202-213,共12页
Background:As is widely known,an increasing number of forest areas were managed to preserve and enhance the health of forest ecosystems.However,previous research on forest management has often overlooked the importanc... Background:As is widely known,an increasing number of forest areas were managed to preserve and enhance the health of forest ecosystems.However,previous research on forest management has often overlooked the importance of structure-based.Aims:Our objectives were to define the direction of structure-based forest management.Subsequently,we investigated the relationships between forest structure and the regeneration,growth,and mortality of trees under different thinning treatments.Ultimately,the drivers of forest structural change were explored.Methods:On the basis of 92 sites selected from northeastern China,with different recovery time (from 1 to 15years) and different thinning intensities (0–59.9%) since the last thinning.Principal component analysis (PCA)identified relationships among factors determining forest spatial structure.The structural equation model (SEM)was used to analyze the driving factors behind the changes in forest spatial structure after thinning.Results:Light thinning (0–20%trees removed) promoted forest regeneration,and heavy thinning (over 35% of trees removed) facilitated forest growth.However,only moderate thinning (20%–35%trees removed) created a reasonable spatial structure.While dead trees were clustered,and they were hardly affected by thinning intensity.Additionally,thinning intensity,recovery time,and altitude indirectly improve the spatial structure of the forest by influencing diameter at breast height (DBH) and canopy area.Conclusion:Creating larger DBH and canopy area through thinning will promote the formation of complex forest structures,which cultivates healthy and stable forests. 展开更多
关键词 THINNING Natural secondary forest Spatial structure Dynamic changes Growth factors Structural equation modeling
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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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Analysis of the inflection points of height-diameter models
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作者 Tzeng Yih Lam Mark J.Ducey 《Forest Ecosystems》 SCIE CSCD 2024年第4期414-422,共9页
The inflection point is an important feature of sigmoidal height-diameter(H-D)models.It is often cited as one of the properties favoring sigmoidal model forms.However,there are very few studies analyzing the inflectio... The inflection point is an important feature of sigmoidal height-diameter(H-D)models.It is often cited as one of the properties favoring sigmoidal model forms.However,there are very few studies analyzing the inflection points of H-D models.The goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional dataset.The six models were the Wykoff(WYK),Schumacher(SCH),Curtis(CUR),HossfeldⅣ(HOS),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)models.The models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial distribution.The distributions of the estimated inflection points were similar between the two-parameter models WYK,SCH,and CUR,but were different between the threeparameter models HOS,VBR,and GPZ.GPZ produced some of the largest inflection points.HOS and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree species.Evergreen species or decreasing shade tolerance resulted in larger inflection points.The trends in the estimated inflection points of HOS and VBR were entirely opposite across the landscape.Furthermore,HOS could produce concave H-D curves for portions of the landscape.Based on the studied behaviors,the choice between two-parameter models may not matter.We recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on one.Believing sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with one.Our study highlights the need to integrate analysis of inflection points into modeling H-D relationships. 展开更多
关键词 CONCAVITY Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling Points of inflection Species-specific models
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Endohepatology:Arrival at the frontier of interventional endosonography
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作者 Shane P Selvanderan Eric Lam Neal Shahidi 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2397-2401,共5页
Endohepatology describes the emerging field where diagnostic and therapeutic endoscopic ultrasound(EUS)are used for the diagnosis and management of liver disease and its sequelae.In this editorial we comment on the ar... Endohepatology describes the emerging field where diagnostic and therapeutic endoscopic ultrasound(EUS)are used for the diagnosis and management of liver disease and its sequelae.In this editorial we comment on the article by Gadour et al.The spectrum of EUS-guided procedures includes liver parenchymal and lesional biopsy,abscess drainage,treatment of focal liver lesions,diagnosis of portal hypertension and management of gastric varices.The data suggest that the application of EUS to hepatology is technically feasible and safe,heralding the arrival at a new frontier for EUS.More data,specifically randomised trials comparing EUS to interventional radiology techniques,and continued partnership between endoscopy and hepatology are required to see this field establish itself outside expert tertiary centres. 展开更多
关键词 CANCER CIRRHOSIS ENDOSCOPY Endoscopic ultrasound Liver disease
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Gastric cystica profunda:Another indication for minimally invasive endoscopic resection techniques?
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作者 Harjot K Bedi Douglas Motomura Neal Shahidi 《World Journal of Gastroenterology》 SCIE CAS 2024年第27期3278-3283,共6页
Gastric cancer presents a significant global health burden,as it is the fifth most common malignancy and fourth leading cause of cancer mortality worldwide.Variations in incidence rates across regions underscores the ... Gastric cancer presents a significant global health burden,as it is the fifth most common malignancy and fourth leading cause of cancer mortality worldwide.Variations in incidence rates across regions underscores the multifactorial etiology of this disease.The overall 5-year survival rate remains low despite advances in its diagnosis and treatment.Although surgical gastrectomy was previously standard-of-care,endoscopic resection techniques,including endoscopic mucosal resection and endoscopic submucosal dissection(ESD)have emerged as effective alternatives for early lesions.Compared to surgical resection,endoscopic resection techniques have comparable 5-year survival rates,reduced treatment-related adverse events,shorter hospital stays and lower costs.ESD also enables en bloc resection,thus affording organ-sparing curative endoscopic resection for early cancers.In this editorial,we comment on the recent publication by Geng et al regarding gastric cystica profunda(GCP).GCP is a rare gastric pseudotumour with the potential for malignant progression.GCP presents a diagnostic challenge due to its nonspecific clinical manifestations and varied endoscopic appearance.There are several gaps in the literature regarding the diagnosis and management of GCP which warrants further research to standardize patient management.Advances in endoscopic resection techniques offer promising avenues for GCP and early gastric cancers. 展开更多
关键词 Early gastric cancer ENDOSCOPY Endoscopic submucosal dissection Gastric cystica profunda
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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses
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作者 Ting Wang Qing Xu +4 位作者 Beibei Zhang Deqiang Gao Ying Zhang Jing Jiang Haijun Zuo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期42-53,共12页
Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and... Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates. 展开更多
关键词 Stable carbon isotope Water use efficiency THINNING Understory removal Photosynthetic capacity Needle water potential
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Lithium-ion and solvent co-intercalation enhancing the energy density of fluorinated graphene cathode
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作者 Hao Wang Jie Jiang +5 位作者 Pengyu Chen Zhenrui Wu Xiaobin Niu Chuying Ouyang Jian Liu Liping Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期208-215,I0006,共9页
Fluorinated carbons CF_xhold the highest theoretical energy density(e.g.,2180 W h kg^(-1)when x=1)among all cathode materials of lithium primary batteries.However,the low conductivity and severe polarization limit it ... Fluorinated carbons CF_xhold the highest theoretical energy density(e.g.,2180 W h kg^(-1)when x=1)among all cathode materials of lithium primary batteries.However,the low conductivity and severe polarization limit it to achieve its theory.In this study,we design a new electrolyte,namely 1 M LiBF_(4)DMSO:DOL(1:9 vol.),achieving a high energy density in Li/CF_xprimary cells.The DMSO with a small molecular size and high donor number successfully solvates Li^(+)into a defined Li^(+)-solvation structure.Such solvated Li^(+)can intercalate into the large-spacing carbon layers and achieve an improved capacity.Consequently,when discharged to 1.0 V,the CF_(1.12)cathode demonstrates a specific capacity of 1944 m A h g^(-1)with a specific energy density of 3793 W h kg^(-1).This strategy demonstrates that designing the electrolyte is powerful in improving the electrochemical performance of CF_(x) cathode. 展开更多
关键词 Fluorinated carbon Conversion reaction High-energy-density primary battery Li^(+)-solvation structure Solvent co-intercalation
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Effect of coir geotextile and geocell on ephemeral gully erosion in the Mollisol region of Northeast China
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作者 QIN Xijin SUN Yiqiu +4 位作者 ZHANG Yan GUAN Yinghui WU Hailong WANG Xinyu WANG Guangyu 《Journal of Arid Land》 SCIE CSCD 2024年第4期518-530,共13页
The unique geomorphological features and farming methods in the Mollisol region of Northeast China increase water catchment flow and aggravate the erosion of ephemeral gully(EG).Vegetation suffers from rain erosion an... The unique geomorphological features and farming methods in the Mollisol region of Northeast China increase water catchment flow and aggravate the erosion of ephemeral gully(EG).Vegetation suffers from rain erosion and damage during the growth stage,which brings serious problems to the restoration of grass in the early stage.Therefore,effects of coir geotextile and geocell on EG erosion under four confluence intensities were researched in this study.Results of the simulated water discharge erosion test showed that when the confluence strength was less than 30 L/min,geocell and coir geotextile had a good effect on controlling EG erosion,and sediment yield of geocell and coir geotextile was reduced by 25.95%–37.82%and 73.73%–88.96%,respectively.However,when confluence intensity increased to 40 L/min,protective effect of coir geotextile decreased,and sediment yield rate increased sharply by 189.03%.When confluence intensity increased to 50 L/min,the protective effect of coir geotextile was lost.On the other hand,geocell showed that the greater the flow rate,the better the protective effect.In addition,with the increase in confluence intensity,erosion pattern of coir geotextile developed from sheet erosion to intermittent fall and then to completion of main rill,and the protective effect was gradually weakened.In contrast,the protective effect of EG under geocell was gradually enhanced from the continuous rill to the intermittent rill and finally to the intermittent fall.This study shows that coir geotextile and geocell can prevent EG erosion,and the effect of geocell is better than that of coir geotextile on the surface of EG. 展开更多
关键词 GEOCELL coir geotextile ephemeral gully confluence intensity erosion control
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Enhancing XRF sensor-based sorting of porphyritic copper ore using particle swarm optimization-support vector machine(PSO-SVM)algorithm
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作者 Zhengyu Liu Jue Kou +5 位作者 Zengxin Yan Peilong Wang Chang Liu Chunbao Sun Anlin Shao Bern Klein 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期545-556,共12页
X-ray fluorescence(XRF)sensor-based ore sorting enables efficient beneficiation of heterogeneous ores,while intraparticle heterogeneity can cause significant grade detection errors,leading to misclassifications and hi... X-ray fluorescence(XRF)sensor-based ore sorting enables efficient beneficiation of heterogeneous ores,while intraparticle heterogeneity can cause significant grade detection errors,leading to misclassifications and hindering widespread technology adoption.Accurate classification models are crucial to determine if actual grade exceeds the sorting threshold using localized XRF signals.Previous studies mainly used linear regression(LR)algorithms including simple linear regression(SLR),multivariable linear regression(MLR),and multivariable linear regression with interaction(MLRI)but often fell short attaining satisfactory results.This study employed the particle swarm optimization support vector machine(PSO-SVM)algorithm for sorting porphyritic copper ore pebble.Lab-scale results showed PSO-SVM out-performed LR and raw data(RD)models and the significant interaction effects among input features was observed.Despite poor input data quality,PSO-SVM demonstrated exceptional capabilities.Lab-scale sorting achieved 93.0%accuracy,0.24%grade increase,84.94%recovery rate,57.02%discard rate,and a remarkable 39.62 yuan/t net smelter return(NSR)increase compared to no sorting.These improvements were achieved by the PSO-SVM model with optimized input combinations and highest data quality(T=10,T is XRF testing times).The unsuitability of LR methods for XRF sensor-based sorting of investigated sample is illustrated.Input element selection and mineral association analysis elucidate element importance and influence mechanisms. 展开更多
关键词 XRF sensor-based sorting PSO-SVM algorithm Copper ore pebble Receiver operating curve(ROC) Net smelter return(NSR)
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Monogenic features of urolithiasis: A comprehensive review
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作者 Kyo Chul Koo Abdulghafour Halawani +2 位作者 Victor K.F.Wong Dirk Lange Ben H.Chew 《Asian Journal of Urology》 CSCD 2024年第2期169-179,共11页
Objective: Urolithiasis formation has been attributed to environmental and dietary factors. However, evidence is accumulating that genetic background can contribute to urolithiasis formation. Advancements in the ident... Objective: Urolithiasis formation has been attributed to environmental and dietary factors. However, evidence is accumulating that genetic background can contribute to urolithiasis formation. Advancements in the identification of monogenic causes using high-throughput sequencing technologies have shown that urolithiasis has a strong heritable component.Methods: This review describes monogenic factors implicated in a genetic predisposition to urolithiasis. Peer-reviewed journals were evaluated by a PubMed search until July 2023 to summarize disorders associated with monogenic traits, and discuss clinical implications of identification of patients genetically susceptible to urolithiasis formation.Results: Given that more than 80% of urolithiases cases are associated with calcium accumulation, studies have focused mainly on monogenetic contributors to hypercalciuric urolithiases, leading to the identification of receptors, channels, and transporters involved in the regulation of calcium renal tubular reabsorption. Nevertheless, available candidate genes and linkage methods have a low resolution for evaluation of the effects of genetic components versus those of environmental, dietary, and hormonal factors, and genotypes remain undetermined in the majority of urolithiasis formers.Conclusion: The pathophysiology underlying urolithiasis formation is complex and multifactorial, but evidence strongly suggests the existence of numerous monogenic causes of urolithiasis in humans. 展开更多
关键词 Gene Genetic expression Inheritance pattern UROLITHIASIS
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Nearest Neighbor Sampling of Point Sets Using Rays
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作者 Liangchen Liu Louis Ly +1 位作者 Colin B.Macdonald Richard Tsai 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1131-1174,共44页
We propose a new framework for the sampling,compression,and analysis of distributions of point sets and other geometric objects embedded in Euclidean spaces.Our approach involves constructing a tensor called the RaySe... We propose a new framework for the sampling,compression,and analysis of distributions of point sets and other geometric objects embedded in Euclidean spaces.Our approach involves constructing a tensor called the RaySense sketch,which captures nearest neighbors from the underlying geometry of points along a set of rays.We explore various operations that can be performed on the RaySense sketch,leading to different properties and potential applications.Statistical information about the data set can be extracted from the sketch,independent of the ray set.Line integrals on point sets can be efficiently computed using the sketch.We also present several examples illustrating applications of the proposed strategy in practical scenarios. 展开更多
关键词 Point clouds Sampling CLASSIFICATION REGISTRATION Deep learning Voronoi cell analysis
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T1 colorectal cancer management in the era of minimally invasive endoscopic resection
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作者 Shirley Xue Jiang Aein Zarrin Neal Shahidi 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2284-2294,共11页
T1 colorectal cancer(CRC),defined by tumor invasion confined to the submucosa,has historically been managed by surgery.Improved understanding of recurrence and lymph node metastases risk,coupled with advances in endos... T1 colorectal cancer(CRC),defined by tumor invasion confined to the submucosa,has historically been managed by surgery.Improved understanding of recurrence and lymph node metastases risk,coupled with advances in endoscopic resection techniques,have led to an increasing capacity for organ-sparing local excision.Minimally invasive management of T1 CRC begins with optical evaluation of the lesion to diagnose invasive disease and quantify depth of invasion,which informs therapeutic decision making.Modality selection between various available endoscopic resection techniques depends upon lesion characteristics,technique risk-benefit profiles,and location-specific implications.Following endoscopic resection,established histopathology features determine the risk of recurrence and subsequent management including surveillance or adjuvant surgical excision.The management of non-operative candidates deviates from conventional recommendations with emerging treatment strategies in select populations. 展开更多
关键词 Cancer COLONOSCOPY ENDOSCOPY POLYP Surgery
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VR-based digital twin for remote monitoring of mining equipment:Architecture and a case study
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作者 Jovana PLAVŠIĆ Ilija MIŠKOVIĆNorman BKeevil 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期100-112,共13页
Background Traditional methods for monitoring mining equipment rely primarily on visual inspections,which are time-consuming,inefficient,and hazardous.This article introduces a novel approach to monitoring mission-cri... Background Traditional methods for monitoring mining equipment rely primarily on visual inspections,which are time-consuming,inefficient,and hazardous.This article introduces a novel approach to monitoring mission-critical systems and services in the mining industry by integrating virtual reality(VR)and digital twin(DT)technologies.VR-based DTs enable remote equipment monitoring,advanced analysis of machine health,enhanced visualization,and improved decision making.Methods This article presents an architecture for VR-based DT development,including the developmental stages,activities,and stakeholders involved.A case study on the condition monitoring of a conveyor belt using real-time synthetic vibration sensor data was conducted using the proposed methodology.The study demonstrated the application of the methodology in remote monitoring and identified the need for further development for implementation in active mining operations.The article also discusses interdisciplinarity,choice of tools,computational resources,time and cost,human involvement,user acceptance,frequency of inspection,multiuser environment,potential risks,and applications beyond the mining industry.Results The findings of this study provide a foundation for future research in the domain of VR-based DTs for remote equipment monitoring and a novel application area for VR in mining. 展开更多
关键词 Virtual reality Digital twin Condition monitoring Mining equipment
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Sexual dimorphism of G protein-coupled receptor signaling in the brain
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作者 Sara Aljoudi Hamdan Hamdan Khaled S.Abd-Elrahman 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1635-1636,共2页
G protein-coupled receptors(GPCRs)represent the most substantial family of membrane receptors that are targeted by U.S.Food and Drug Administration-approved drugs.Much of the preclinical research to understand the pha... G protein-coupled receptors(GPCRs)represent the most substantial family of membrane receptors that are targeted by U.S.Food and Drug Administration-approved drugs.Much of the preclinical research to understand the pharmacology of many membrane receptors including GPCRs is derived from studies in male animal models(Karp and Reavey,2019). 展开更多
关键词 DRUGS CLINICAL TARGETED
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