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Innovative strategies to increase cardiac donor availability
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作者 Benjamin Alexander Herra Javed +3 位作者 Anshaal Furrukh Krittika Joshi Louis Steen Taufiek Konrad Rajab 《World Journal of Transplantation》 2025年第3期62-69,共8页
Heart transplantation is a life-saving procedure for many people throughout the world.Data shows that in 2024,there was an increase in the volume of adult heart transplantation in the United States even as there was a... Heart transplantation is a life-saving procedure for many people throughout the world.Data shows that in 2024,there was an increase in the volume of adult heart transplantation in the United States even as there was a decrease in the volume of pediatric heart transplantation to the lowest volume in a decade.Organ availability remains a major limiting factor affecting transplant volume.This mandates that innovation must take place to increase the supply of donor organs.While some strategies such as donation after cardiac death,hepatitis C virus+transplantation,and ABO-incompatible transplantation have increased the pool for donation,it still falls short of meeting the demand.Other proposed strategies include splitting the donor heart to provide multiple partial heart transplants,domino partial heart transplantation,changes in legislation including opt-out legislation,and xenotransplantation.Further evolution and refinement of these strategies will make a meaningful impact on patients awaiting life-saving heart transplants. 展开更多
关键词 Heart transplantation Partial heart translation Domino transplantation Organ availability Valvular transplantation
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Effects of nitrosamine impurities on the availability of Reference Listed drugs in China
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作者 Dongsheng Yang Jianzhao Niu +2 位作者 Yufei Feng Nian Liu Lingyun Ma 《Journal of Chinese Pharmaceutical Sciences》 2025年第1期75-81,共7页
The Reference Listed drug(RLD)plays a critical role in the development and research of generic medicinal products,serving as the comparator product used in the marketing authorization application of new generic medici... The Reference Listed drug(RLD)plays a critical role in the development and research of generic medicinal products,serving as the comparator product used in the marketing authorization application of new generic medicinal product and re-evaluation of generic medicinal product.In China,RLDs are sourced from various origins,but their quality and market availability can be constrained by multiple factors,including emergent issues such as nitrosamine impurities.Five classes of medicinal products have been reported to be at risk for containing nitrosamine impurities:sartan-based medicines,metformin-containing products,ranitidine medicines,rifampicin medicines,and Champix.This paper explores the control strategies implemented by drug regulatory agencies in the United States and the European Union to manage nitrosamine impurities and assesses their impact on the market availability and quality of RLDs in China.The aim is to offer valuable insights for generic drug manufacturers and regulatory bodies both domestically and internationally. 展开更多
关键词 Reference Listed drugs Nitrosamine impurities Food and Drug Administration European Medicines Agency availABILITY
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A simplified ratiometric fluorescent sensing strategy for enhanced detection of alkaline phosphatase employing Prussian blue nanozymes and commercially available chromogen
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作者 Mingyue Luo Kehui Zhang +5 位作者 Honghong Rao Jianying Li Xin Xue Panpan Sun Xiaoquan Lu Zhonghua Xue 《Chinese Chemical Letters》 2025年第9期413-418,共6页
The traditional nanozymes-based ratiometric fluorescence sensing platforms usually necessitate the supplementary addition of fluorescent probes,therefore greatly restricting its convenient and broad application.In thi... The traditional nanozymes-based ratiometric fluorescence sensing platforms usually necessitate the supplementary addition of fluorescent probes,therefore greatly restricting its convenient and broad application.In this study,a highly sensitive and selective ratiometric fluorescence platform for alkaline phosphatase(ALP)detection was established,only employing Prussian blue(PB)nanozymes and a commercially available chromogen of o-phenylenediamine(OPD).PB nanozymes with remarkable peroxidaselike(POD-like)activity can effectively catalyze OPD chromogen to yield 2,3-diaminophenazine(OPDox)with an intense yellow fluorescence at 573 nm emission peak.Target ALP can facilitate ascorbic acid 2-phosphate(AAP)dephosphorylation to generate phosphate and ascorbic acid(AA).Significantly,both these two resultant hydrolysis products could effectively decrease the OPDox generation via a dualpath based inhibition on the PB nanozymes POD-like activity.On the other hand,the generated dehydroascorbic acid(DHAA)from AA oxidation would exclusively react with OPD chromogen to yield3-(dihydroxyethyl)furo[3,4-b]quinoxaline-1-one(DFQ)with a strong blue fluorescent signal at 434nm,which further providing a significant enhancement on the sensing selectivity of ALP detection.As a result,an increased yellow fluorescence of OPDox and decreased blue fluorescence of DFQ could be clearly observed with different ALP addition.A robust linear relationship between the fluorescence ratio of F_(434)/F_(573)and ALP activity ranging from 0.25U/L to 6U/L was obtained,with a low detection limit of 0.112 U/L.This proposed method demonstrates high sensitivity,excellent selectivity,cost-effectiveness,and operational simplicity,yet enabling an effective detection of ALP levels in human serum. 展开更多
关键词 Ratiometric fluorescence Prussian blue nanozymes Peroxidase-like activity Commercially available chromogens Alkaline phosphatase
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Organic matter accelerated microbial iron reduction and available phosphorus release in reflooded paddy soils
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作者 Xipeng Liu Yuchen Shu +5 位作者 Kejie Li Haotian Wang Qingfang Bi Haibo Wang Chengliang Sun Xianyong Lin 《Soil Ecology Letters》 2025年第3期155-168,共14页
Organic fertilization may influence soil carbon−iron(C-Fe)cycling and enhance phosphorus(P)availability,yet the direct connection between soil organic matter molecules and iron-reducing processes in long-term fertiliz... Organic fertilization may influence soil carbon−iron(C-Fe)cycling and enhance phosphorus(P)availability,yet the direct connection between soil organic matter molecules and iron-reducing processes in long-term fertilized paddy soils remains underexplored.In this study,we conducted a microcosm experiment using paddy soils treated with six distinct fertilization regimes involving varying P and organic matter inputs up to five years.We assessed P activation under reflooding conditions,evaluated Fe reduction,and characterized dissolved organic matter(DOM)at the molecular level using Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS),alongside profiling soil microbial community composition via high-throughput sequencing.Our findings revealed that after 25 days of reflooding,soil Olsen-P content increased by an average of 73%compared to its initial state,showing a strong correlation with the Fe reduction process.Specifically,treatments involving pig manure application exhibited higher Fe reduction rates and enhanced P activation,highlighting the role of organic matter in facilitating Fe reduction.Examination of Fe-reducing microorganisms revealed that their relative abundance was decoupled from Fe reduction and P release rates,potentially due to limitations of lower soil organic matter content.Further analysis of DOM composition and network structures suggested that high-molecular-weight DOM,particularly lignin,acted as key resources for Fe-reducing microbes,thereby driving Fe reduction and promoting P release.Overall,our study highlights the crucial role of soil DOM in enabling microbial-driven Fe reduction and enhancing P availability,providing insights valuable for sustainable agricultural practices. 展开更多
关键词 manure application P availability soil biogeochemistry microbial carbon mineralization iron-carbon cycling anaerobic soil
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Global distributions and long-term trends of available wave energy based on ERA5 wave reanalysis
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作者 Jian Shi Wei Liu +5 位作者 Haifei Sun Xiangming Cao Yuan Li Chi Zhang Nguyen Viet Thanh Lipeng Zhang 《Acta Oceanologica Sinica》 2025年第6期15-32,共18页
Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wa... Using the ERA5 wave reanalysis,the distributions and trends of global available wave energy storage during 1980−2019 are analyzed.The results show that the available wave energy storage is not only related to total wave energy storage but is also affected by the local available wave probability.Different distributions and trends between the available wave energy and total wave energy storage are observed.Larger values of total wave energy storage are concentrated in the high-latitude westerlies zone,whereas available wave energy storage exhibits greater concentration in the middle-low latitude regions.In each basin,there is a notable upward trend in both total wave energy storage and available wave energy storage.However,the northern Hemisphere(NH)exhibits an increasing trend in available wave probability,whereas the southern Hemisphere(SH)experiences a decreasing trend.This divergence contributes to the spatial distributions of available wave energy storage becoming increasingly uniform.These trends in wave energy are primarily influenced by changes in significant wave height.Although the increasing trend of significant wave height across all frequency ranges induces the growth of total wave energy storage,only the increasing of wave heights falling in 1.3−4 m can cause the growth of available wave energy storage.The consistent increasing rates of wave height under different mean levels contribute to the divergent trends in available wave probability. 展开更多
关键词 ERA5 available wave energy spatial distribution long-term trends wave energy converter
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Improving kinetic modelling of magnesium hydrogenation by including interfacial polarisation and interstitial hydrogen clustering behaviour within the site availability model
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作者 Marcus J.Adams Alastair Stuart +1 位作者 Gavin S.Walker David M.Grant 《Journal of Magnesium and Alloys》 2025年第5期2009-2022,共14页
Recent work analysing magnesium hydrogenation using Reflecting Electron Energy Loss Spectroscopy(REELS)and Density Function Theory(DFT)has indicated interfacial polarisation and interstitial hydrogen clustering influe... Recent work analysing magnesium hydrogenation using Reflecting Electron Energy Loss Spectroscopy(REELS)and Density Function Theory(DFT)has indicated interfacial polarisation and interstitial hydrogen clustering influence the reaction rate.The site availability model has been modified to include interstitial hydrogen clustering within the site availability factor and interface polarisation using interface treatment.The new model,SAM-CV-S,has demonstrated improved modelling of magnesium hydrogenation across wide operating conditions,such as temperatures from 330 to 400℃and pressures up to 40 bar.This wide applicability makes it a robust model that can be used to simulate bed performance in solid-state hydrogen stores.Thus,the site availability factor successfully combines interstitial hydrogen clustering with thermal resistance effects,which are known to strongly influence metal hydride reactor designs at scale.The next phase of the model is to incorporate a predictive hydrogen capacity method into the model. 展开更多
关键词 Magnesium hydrogenation kinetics Site availability factor Interstitial hydrogen clustering Interfacial polarisation
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Biological nitrogen fixation in paddy soils is driven by multiple edaphic factors and available phosphorus is the greatest contributor 被引量:1
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作者 Tianlong HU Yanhui ZHANG +15 位作者 Hui WANG Haiyang JIN Benjuan LIU Zhibin LIN Jing MA Xiaojie WANG Qi LIU Hongtao LIU Zhe CHEN Rong ZHOU Penghui JIN Jianguo ZHU Gang LIU Qicheng BEI Xingwu LIN Zubin XIE 《Pedosphere》 CSCD 2024年第6期993-1001,共9页
Biological nitrogen(N)fixation(BNF)is important for sustainable rice cultivation.Various edaphic factors have been individually evaluated for their effects on BNF in paddy soils.However,no single factor could fully ex... Biological nitrogen(N)fixation(BNF)is important for sustainable rice cultivation.Various edaphic factors have been individually evaluated for their effects on BNF in paddy soils.However,no single factor could fully explain the different soil outcomes.Paddy BNF is more likely to be simultaneously influenced to various degrees by combinations of several edaphic factors;however,the relative importance of the interaction of multiple edaphic factors on the regulation of BNF in paddy soils is still unclear.Twenty-seven paddy soil samples with different soil properties were collected from the major rice cropping areas in Southwest and Northeast China to determine the edaphic factors affecting paddy BNF amount.Rice was transplanted into pots filled with paddy soils and grown in a^(15)N_2-enriched airtight chamber.Estimation of BNF was based on the measurements of^(15)N enrichment in the paddy soils and rice plants at the end of a 77-d incubation period.The BNF amounts ranged from 0.66 to 12.3 kg ha^(-1),with a significant positive relationship with available phosphorus(AP)and significant quadratic relationships with available molybdenum(AMo)and total N(TN).Available P explained 42%of the observed variation in BNF,TN explained 17%,and AMo explained 13%.The specific interaction between soil cation exchange capacity and available soil N(as determined by rice N uptake)accounted for 28%of the variation in BNF.The BNF amount was decreased when AP was<14 mg kg^(-1),AMo<0.09 mg kg^(-1),or TN was>3.2 g kg^(-1).These results provide valuable benchmarks that could be used to guide farmers in managing paddy soils to improve the potential contribution of paddy BNF to soil fertility. 展开更多
关键词 available molybdenum available soil nitrogen influencing factors multiplicative effect rice field soil fertility
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Future changes in precipitation and water availability over the Tibetan Plateau projected by CMIP6 models constrained by climate sensitivity 被引量:1
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作者 Hui Qiu Tianjun Zhou +3 位作者 Liwei Zou Jie Jiang Xiaolong Chen Shuai Hu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期40-46,共7页
Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assesse... Precipitation projections over the Tibetan Plateau(TP)show diversity among existing studies,partly due to model uncertainty.How to develop a reliable projection remains inconclusive.Here,based on the IPCC AR6–assessed likely range of equilibrium climate sensitivity(ECS)and the climatological precipitation performance,the authors constrain the CMIP6(phase 6 of the Coupled Model Intercomparison Project)model projection of summer precipitation and water availability over the TP.The best estimates of precipitation changes are 0.24,0.25,and 0.45 mm d^(−1)(5.9%,6.1%,and 11.2%)under the Shared Socioeconomic Pathway(SSP)scenarios of SSP1–2.6,SSP2–4.5,and SSP5–8.5 from 2050–2099 relative to 1965–2014,respectively.The corresponding constrained projections of water availability measured by precipitation minus evaporation(P–E)are 0.10,0.09,and 0.22 mm d^(−1)(5.7%,4.9%,and 13.2%),respectively.The increase of precipitation and P–E projected by the high-ECS models,whose ECS values are higher than the upper limit of the likely range,are about 1.7 times larger than those estimated by constrained projections.Spatially,there is a larger increase in precipitation and P–E over the eastern TP,while the western part shows a relatively weak difference in precipitation and a drier trend in P–E.The wetter TP projected by the high-ECS models resulted from both an approximately 1.2–1.4 times stronger hydrological sensitivity and additional warming of 0.6℃–1.2℃under all three scenarios during 2050–2099.This study emphasizes that selecting climate models with climate sensitivity within the likely range is crucial to reducing the uncertainty in the projection of TP precipitation and water availability changes. 展开更多
关键词 Tibetan plateau Climate sensitivity Precipitation projection Water availability projection
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Effect of Organic Waste and Inorganic Additives on Organic Matter Transformation and Mineral Availability in Composting Green Waste 被引量:1
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作者 Abderrahim Boutasknit Mohamed Anli +1 位作者 Rachid Lahlali Abdelilah Meddich 《Phyton-International Journal of Experimental Botany》 2024年第9期2227-2249,共23页
Applying organic waste and inorganic additives during composting can be an effective and easy-to-control strategy for optimizing humification,maturation,and the availability of essential mineral elements in compost.In... Applying organic waste and inorganic additives during composting can be an effective and easy-to-control strategy for optimizing humification,maturation,and the availability of essential mineral elements in compost.In this respect,this study aims to evaluate the effect of organic(olive-mill waste and horse manure)and inorganic(phosphogypsum)additives on the evolution of maturity indices,aromatic compounds,and nutrient availability during composting.Four mixtures[horse manure+green waste(M1),olive-mill+green waste(M2),sewage-sludge+phos-phogypsum+green waste(M3),and green waste(M4)]were carried out.Physicochemical(temperature,pH,phosphorus,nitrogen,and carbon-to-nitrogen(C/N)ratio),infrared-spectroscopic,and phytotoxicity were monitored.The results showed that(in)organic additives have a positive effect on maturity and humification indices,pH stability,and the phosphorus and nitrogen availability in the composts produced.The horse manure additive reduced the carbon and increased the nitrogen,reducing the C/N ratio.Phosphogypsum and olive-mill reduced phytotoxicity,boosting the nitrogen and phosphorus availability of in composts.Fourier transform infrared spectroscopy(FT-IR)analysis revealed that phosphogypsum and olive-mill addition improved the aromatic compounds and reduced the aliphatic ones in M3 and M4 com-posts.These results suggest new approaches to promoting maturity and stability,as well as phosphorus and nitrogen availability in composts,through better use of organic waste and inorganic additives in composting. 展开更多
关键词 Biotransformation process (in)organic additives horse manure olive-mill sewage sludge and phosphogypsum green wastes phosphorus availability
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Influence of prey availability on the movement pattern of breeding saker falcons(Falco cherrug)in Mongolia
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作者 Batbayar Bold Md.Lutfor Rahman +3 位作者 Gankhuyag Purev-Ochir Amarsaikhan Saruul Xiangjiang Zhan Andrew Dixon 《Current Zoology》 SCIE CAS CSCD 2024年第6期810-820,共11页
As an apex predator in arid steppe,saker falcon plays a crucial role in maintaining ecosystem balance.Understanding their movement patterns concerning conspecific competition and prey availability is important for the... As an apex predator in arid steppe,saker falcon plays a crucial role in maintaining ecosystem balance.Understanding their movement patterns concerning conspecific competition and prey availability is important for their conservation.We aim to understand how movement pattern of breeding saker falcons relates to prey availability.Twelve adult sakers were tracked during the breeding seasons,using satellite transmitters.Throughout the breeding season,sakers exhibited territorial behavior,with minimal overlap in range use among neighboring conspecifics.Males occupied larger areas(mean=2,397 ha,median=1,221 ha),compared to females(mean=1,241 ha,median=554 ha),and it remained consistent throughout breeding season.Female home range size increased notably during a late nestling stage and post-fledging dependence periods,indicating release from brooding constraints.Notably,we found a negative relationship between male home range size and prey availability.In high rodent density areas,males occupied smaller areas(mean=1,135 ha,median=1,034 ha),contrasting with low rodent density areas(mean=6,815 ha,median=6,516 ha).However,no significant relationship was observed between female home range size and prey availability.We also noted instances of nest abandonment and early dispersal behavior in some females,potentially influenced by a handicapping effect of tagging.Our findings offer valuable insight into how prey availability shapes saker falcon space use and defines their spatial requirements for successful breeding.This knowledge is crucial for the conservation and management of globally endangered saker falcons,informing targeted habitat protection and resource management strategies. 展开更多
关键词 birds of prey distance from the nest home range prey availability TERRITORY tagging effect
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Improving Network Availability through Optimized Multipath Routing and Incremental Deployment Strategies
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作者 Wei Zhang Haijun Geng 《Computers, Materials & Continua》 SCIE EI 2024年第7期427-448,共22页
Currently,distributed routing protocols are constrained by offering a single path between any pair of nodes,thereby limiting the potential throughput and overall network performance.This approach not only restricts th... Currently,distributed routing protocols are constrained by offering a single path between any pair of nodes,thereby limiting the potential throughput and overall network performance.This approach not only restricts the flow of data but also makes the network susceptible to failures in case the primary path is disrupted.In contrast,routing protocols that leverage multiple paths within the network offer a more resilient and efficient solution.Multipath routing,as a fundamental concept,surpasses the limitations of traditional shortest path first protocols.It not only redirects traffic to unused resources,effectively mitigating network congestion,but also ensures load balancing across the network.This optimization significantly improves network utilization and boosts the overall performance,making it a widely recognized efficient method for enhancing network reliability.To further strengthen network resilience against failures,we introduce a routing scheme known as Multiple Nodes with at least Two Choices(MNTC).This innovative approach aims to significantly enhance network availability by providing each node with at least two routing choices.By doing so,it not only reduces the dependency on a single path but also creates redundant paths that can be utilized in case of failures,thereby enhancing the overall resilience of the network.To ensure the optimal placement of nodes,we propose three incremental deployment algorithms.These algorithms carefully select the most suitable set of nodes for deployment,taking into account various factors such as node connectivity,traffic patterns,and network topology.By deployingMNTCon a carefully chosen set of nodes,we can significantly enhance network reliability without the need for a complete overhaul of the existing infrastructure.We have conducted extensive evaluations of MNTC in diverse topological spaces,demonstrating its effectiveness in maintaining high network availability with minimal path stretch.The results are impressive,showing that even when implemented on just 60%of nodes,our incremental deployment method significantly boosts network availability.This underscores the potential of MNTC in enhancing network resilience and performance,making it a viable solution for modern networks facing increasing demands and complexities.The algorithms OSPF,TBFH,DC and LFC perform fast rerouting based on strict conditions,while MNTC is not restricted by these conditions.In five real network topologies,the average network availability ofMNTCis improved by 14.68%,6.28%,4.76%and 2.84%,respectively,compared with OSPF,TBFH,DC and LFC. 展开更多
关键词 Multipath routing network availability incremental deployment schemes genetic algorithm
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Effects of Different Seed Stem Sizes on the Changes of Available Elements in Rhizosphere Soil of Fritillaria thunbergii Miq.
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作者 Yong PENG Rui PAN +3 位作者 Zhengyan LIU Xiaohong WU Nong ZHOU Wenwu YANG 《Agricultural Biotechnology》 2024年第3期18-23,共6页
[Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F... [Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F.thunbergii Miq.introduced to different places.[Methods]F.thunbergii Miq.from four different provenances including Zhejiang,Nantong and Chongqing were introduced and cultivated in Wanzhou of Chongqing.The contents of available Zn,Fe,Mn,Cu,Mo,N,P,K,Ca and Mg in rhizosphere soil of F.thunbergii Miq.during five growing stages were determined after selecting different stem sizes for field cultivation.[Results]Small stems of Pan an and Ningbo provenances(SSG3,121-160/kg)and middle stems of Nantong and Fengjie provenances(SSG2,81-120/kg)showed higher soil availability.[Conclusions]In the process of introduction and cultivation of F.thunbergii Miq.,high yield and high efficiency can be achieved by selecting smaller seed stems of F.thunbergii Miq. 展开更多
关键词 Fritillaria thunbergii Miq. Different provenances Stem size INTRODUCTION CULTIVATION Soil nutrient element availABILITY
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Toilet Availability and Use in Public Places in Buea: Implications for Public Health
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作者 Mbuwir Charlotte Bongfen 《Occupational Diseases and Environmental Medicine》 2024年第3期161-171,共11页
Toilet facilities in public places are a necessity and are supposed to be present in any public place where people visit. Despite the importance of toilet facilities in public places, there is limited access to toilet... Toilet facilities in public places are a necessity and are supposed to be present in any public place where people visit. Despite the importance of toilet facilities in public places, there is limited access to toilet facilities in public places in Sub-Saharan Africa and this has been a persistent issue. Given that limited studies have been done on availability and use of toilets in public places, this study aimed to fill this research gap. To achieve the objective of the study, a cross-sectional study was used to select participants from the study site. The sample size was 400 after adjustment for non-response. Results from the study showed promising as 95% of public places had a toilet and water for hand washing. However, most of the toilet facilities lacked soap. Toilets in offices and hospitals were perceived to be cleaner and of good quality compared to those in markets and travel agencies. Results also showed that participants hardly used toilets in markets and travel agencies. Toilet facilities in offices and churches were most used, as office toilets were rated clean and of good quality by the participants. The study recommends the need for routine checks by the council to ensure the presence of toilet facilities in public places and the need to sensitise business owners on the importance of having and maintaining toilet facilities in their business establishments. 展开更多
关键词 Toilet Facilities availABILITY USE
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Performance and Availability Evaluation of Big Data Environments in the Private Cloud
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作者 Tarcísio Rolim Erica Sousa 《Journal of Computer and Communications》 2024年第12期266-288,共23页
Cloud computing allows scalability at a lower cost for data analytics in a big data environment. This paradigm considers the dimensioning of resources to process different volumes of data, minimizing the response time... Cloud computing allows scalability at a lower cost for data analytics in a big data environment. This paradigm considers the dimensioning of resources to process different volumes of data, minimizing the response time of big data. This work proposes a performance and availability evaluation of big data environments in the private cloud through a methodology and stochastic and combinatorial models considering performance metrics such as execution times, processor utilization, memory utilization, and availability. The proposed methodology considers objective activities, performance, and availability modeling to evaluate the private cloud environment. A performance model based on stochastic Petrinets is adopted to evaluate the big data environment on the private cloud. Reliability block diagram models are adopted to evaluate the availability of big environment data in the private cloud. Two case studies based on the CloudStack platform and Hadoop cluster are adopted to demonstrate the viability of the proposed methodologies and models. Case Study 1 evaluated the performance metrics of the Hadoop cluster in the private cloud, considering different service offerings, workloads, and the number of data sets. The sentiment analysis technique is used in tweets from users with symptoms of depression to generate the analyzed datasets. Case Study 2 evaluated the availability of big data environments in the private cloud. 展开更多
关键词 Cloud Computing Big Data Hadoop Cluster Performance Evaluation availability Evaluation Reliability Block Diagram Stochastic Petri Nets
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Environmental availability and ecological risk assessment of heavy metals in zinc leaching residue 被引量:26
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作者 闵小波 谢先德 +3 位作者 柴立元 梁彦杰 李密 柯勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期208-218,共11页
Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental acti... Four different methods,namely mineralogical analysis,three-stage BCR sequential extraction procedure,dynamic leaching test and Hakanson Potential Ecological Risk Index Method were used to access the environmental activity and potential ecological risks of heavy metals in zinc leaching residue.The results demonstrate that the environmental activity of heavy metals declines in the following order:CdZnCuAsPb.Potential ecological risk indices for single heavy metal are CdZnCuAsPb.Cd has serious potential ecological risk to the ecological environment and contributes most to the potential toxicity response indices for various heavy metals in the residue. 展开更多
关键词 heavy metals BCR sequential extraction environmental availability leaching toxicity dynamic leaching potential ecological risk index method zinc leaching residue
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AVAILABILITY SIMULATION OF MULTI-COMPONENT SYSTEM BASED ON OPPORTUNISTIC MAINTENANCE POLICY 被引量:5
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作者 蔡景 左洪福 吕德峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期219-223,共5页
A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance ti... A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance time can be shared by more than one component, and the system availability can be improved. Then, the generation characteristics of the random failure time are researched based on the replacement maintenance and the minima[ maintenance. Furthermore, by choosing the opportunistic replacement ages of each component as opti- mized variables, a simulation algorithm based on an opportunistic maintenance policy is designed to maximize the total availability. Finally, the simulation result shows the validity of the algorithm by an example. 展开更多
关键词 availABILITY multi-component system ALGORITHMS opportunistic maintenance minimal maintenance
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Available parking space occupancy change characteristics and short-term forecasting model 被引量:6
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作者 季彦婕 王炜 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期604-608,共5页
Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-secti... Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-sections are periodical and self-similar, and the fluctuation of the APSO increases with the decrease in time-sections. Taking the short-time change behavior into account, an APSO forecasting model combined wavelet analysis and a weighted Markov chain is presented. In this model, an original APSO time series is first decomposed by wavelet analysis, and the results include low frequency signals representing the basic trends of APSO and several high frequency signals representing disturbances of the APSO. Then different Markov models are used to forecast the changes of low and high frequency signals, respectively. Finally, integrating the predicted results induces the final forecasted APSO. A case study verifies the applicability of the proposed model. The comparisons between measured and forecasted results show that the model is a competent model and its accuracy relies on real-time update of the APSO database. 展开更多
关键词 available parking space occupancy change characteristics short-term forecasting wavelet analysis weighted Markov chain
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Effects of freeze-thaw on soil nitrogen and phosphorus availability at the Keerqin Sandy Lands,China 被引量:3
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作者 赵琼 曾德慧 范志平 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期44-48,共5页
A laboratory simulated freeze-thaw was conducted to determine the effects of freeze-thaw on soil nutrient availability in temperate semi-arid regions. Soil samples were collected from sandy soils (0-20 cm) of three ... A laboratory simulated freeze-thaw was conducted to determine the effects of freeze-thaw on soil nutrient availability in temperate semi-arid regions. Soil samples were collected from sandy soils (0-20 cm) of three typical ecosystems (grassland, Mongolian pine plantation and poplar plantation) in southeastern Keerqin Sandy Lands of China and subjected to freeze-thaw treatment (-12℃ for 10 days, then r 20℃ for 10 days) or incubated at constant temperature (20℃ for 20 days). Concentrations of the soil NO3^--N, NH4^+-N, NaHCO3 extractable inorganic P (LPi) and microbial biomass P (MBP) were determined on three occasions: at the start of the incubation, immediate post-thawing and at the 10th day post-thawing. The results showed that soil net nitrification and N mineralization rates at three sites were negatively affected by freeze-thaw treatment, and decreased by 50%-85% as compared to the control, of which the greatest decline occurred in the soil collected from poplar plantation. In contrast, the concentration of soil NH4^+-N, NaHCO3 extractable inorganic P (LPi) and microbial biomass P were insignificantly influenced by freeze-thaw except that LPi and NH4^+-N showed a slight increase immediate post-thawing. The effects of freeze-thaw on soil N transformation were related to soil biological processes and the relatively constant available P was ascribed to severe soil aridity. 展开更多
关键词 freeze-thaw temperate semi-arid region nitrification phosphorus availability
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element available content The affecting factors Western Jilin
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