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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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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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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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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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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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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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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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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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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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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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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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High efficiency AODV routing protocol based on link availability prediction in MANETs 被引量:2
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作者 刘超 胡爱群 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期489-493,共5页
To cope with the problem of low protocol efficiency of the standard ad hoc on-demand distance vector (AODV) routing protocol with the periodic Hello message broadcast mechanism, a new link availability prediction ba... To cope with the problem of low protocol efficiency of the standard ad hoc on-demand distance vector (AODV) routing protocol with the periodic Hello message broadcast mechanism, a new link availability prediction based strategy is introduced to reduce the amount of Hello messages. In this strategy, a novel wireless link availability prediction model under line-of-sight (LOS) propagation environments is proposed based on which the parameter of Hello Interval in AODV can be dynamically adjusted to achieve the goal of changing the frequency of Hello message broadcasts under different link stability degrees. Simulation results demonstrate that, compared with the standard AODV with the periodic Hello message broadcast mechanism, the proposed protocol effectively reduces unnecessary control message overhead and greatly improves the performance in terms of end-to-end delay and efficiency. 展开更多
关键词 Hello message link availability ad hoc on-demand distance vector routing protocol ad hoc
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Effects of Continuous Irrigation of Biogas Slurry on Forms and Biological Availability of Pb in Soil of a Tea Garden 被引量:1
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作者 刘术新 李赛慧 丁枫华 《Agricultural Science & Technology》 CAS 2017年第4期615-618,共4页
Through indoor culture experiments, the effects of continuous irrigation of biogas slurry on the forms and biological availability of Pb in soil of a tea garden were studied. The results show that continuous irrigatio... Through indoor culture experiments, the effects of continuous irrigation of biogas slurry on the forms and biological availability of Pb in soil of a tea garden were studied. The results show that continuous irrigation of biogas slurry could change the forms of Pb in the soil, and exchangeable Pb, Pb bonded to iron and manganese oxides, and Pb bonded to carbonates transformed to Pb bonded to or- ganic matter and residual Pb in the soil. Among various forms of Pb in the soil, the content of residual Pb was the highest in the soil irrigated with biogas slurry contin- uously in various treatments, accounting for 54.56%, 60.00% and 60.70% in the treatments T1, T2 and T3 respectively. Compared with the CK, the application of bio- gas slurry could decrease the biological activity and biological availability of Pb in the soil obviously, and the reduction of the biological activity was 21.26%-22.83%. In a word, the application of biogas slurry in soil of the tea garden could inhibit the biological activity and biological availability of Pb. 展开更多
关键词 Biogas slurry Tea garden PB FORM Biological availability
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The rhizosphere pH change of Pinus koraiensis seedlings as affected by N sources of different levels and its effect on the availability and uptake of Fe, Mn, Cu and Zn
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作者 陈永亮 韩士杰 +1 位作者 周玉梅 程国玲 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期37-40,83,共4页
Dark brown forest soil was collected from the upper 20 cm soil layer in Changbai Mountain Research Station of Ecosystem, Chinese Academy of Sciences. The soil was amended with two different forms of nitrogen fertilize... Dark brown forest soil was collected from the upper 20 cm soil layer in Changbai Mountain Research Station of Ecosystem, Chinese Academy of Sciences. The soil was amended with two different forms of nitrogen fertilizers: NO3- as Ca(NO3)2, NH4+ as NH4Cl at the concentrations of 50, 100, 200 and 400 mgkg-1 respectively. The experiment was carried out with 2-yr-old Pinus koraiensis seedlings in pot. The pH change of rhizosphere soil and the contents of available Fe, Mn, Cu, and Zn in soil and leaves were analyzed. The result indicated that the addition of NH4--N decreased the rhizosphere pH value, while the addition of NO3--N increased the rhizosphere pH value in contrast with the control treatment. The direction and extent of the pH change mainly depended on N source and its concentrations applied. The rhizosphere pH change had a remarkable influence on the availability of the micronutrients in the rhizosphere, and thereafter affected the nutrient uptake by the seedlings. The contents of available mineral nutrients had a negative correlation with the pH value in the rhizosphere soil. The contents of available mineral nutrients in leaves were positively correlated to the levels of the available nutrients in the rhizosphere soils. 展开更多
关键词 Rhizosphere pH N sources MICRONUTRIENT availability UPTAKE
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The pH change in rhizosphere of Pinus koraiensis seedlings as af-fected by different nitrogen sources and its effect on phosphorus availability
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作者 陈永亮 韩士杰 +2 位作者 邹春静 周玉梅 于霞 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期247-249,277,共4页
Root mat method described by Kuchenbuch and Jungk was used to study the rhizosphere processes. The experi-ment was carried out on two years old Pinus koraiensis seedlings. Soil samples collected from the upper 20-cm s... Root mat method described by Kuchenbuch and Jungk was used to study the rhizosphere processes. The experi-ment was carried out on two years old Pinus koraiensis seedlings. Soil samples collected from the upper 20-cm soil layer in Changbai Mountain were treated with three different forms of nitrogen fertilizers: NO3--N, NH4+-N and NH4NO3. The results showed that the soil pH and available P near the roots were all lower than in the bulk soil in control treatment. NH4+-N applica-tion greatly decreased the soil pH near the roots compared to the control treatment and promoted the absorption of phosphorus, which led to a more remarkable depletion region of available P. On the contrary, the rhizosphere soil pH was higher than in the bulk soil in treatments with NO3--N and retarded the P absorption, which led to a nearly equal available P contents to the bulk soil. In treatment with NH4NO3, the rhizosphere soil pH was only a little lower than that in the control treatment and its effects on P absorption is mediate between the treatments with NH4+-N and NO3--N. 展开更多
关键词 Nitrogen sources Rhizosphere pH available P
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A SOLUTION TO HIGH AVAILABILITY OF OPENSTOCK
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作者 黄志球 左藤真司 李清 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期207-212,共6页
High availability is a critical mission for business system. At first, an instance of business system OPENSTOCK for pharmacy is introduced including both client and server sides. Secondly, a solution to the high avail... High availability is a critical mission for business system. At first, an instance of business system OPENSTOCK for pharmacy is introduced including both client and server sides. Secondly, a solution to the high availability of this system is given in detail, including design and implementation. The essentiality of this solution consists of scope of system information, system parameter tables of service status, schedule strategies of load ba lance and how to acquire system parameters and detect service states. The solution proposed is scalable and application oriented and supporting load balance for high performance and fault tolerate for high reliability. This application system has been applied and verified realistically, and the features of this business system derived in this paper have been achieved. 展开更多
关键词 high availability load balance fault tolerate business system application service provider
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