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Two patients with pneumatosis intestinalis with distinct risk profiles managed conservatively 认领 引用
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作者 Hyun Seok Chai Gwan Jin Park +3 位作者 Young Min Kim Sang Chul Kim Hoon Kim Suk Woo Lee 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2026年第3期273-275,共3页
Pneumatosis intestinalis(PI)is a radiological and pathological finding characterized by gas within the gastrointestinal wall.[1]Although its true incidence is uncertain,autopsy series suggest an overall incidence of a... Pneumatosis intestinalis(PI)is a radiological and pathological finding characterized by gas within the gastrointestinal wall.[1]Although its true incidence is uncertain,autopsy series suggest an overall incidence of approximately 0.03%. 展开更多
关键词 conservative management pneumatosis intestinalis risk profiles radiological pathological finding pneumatosis intestinalis pi
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Clinical outcomes of humeral shaft fractures managed with intramedullary K-wires:A closed reduction approach 认领 引用
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作者 Mohammad Adham Abdulsamad Turki S AlMugren +6 位作者 Abdullah I Saeed Waleed A Alrogy Linah D Alanazi Ohud M Alsaqer Faisal T Alanbar Abdulrahman H Alfarraj Ziad A Aljaafri 《World Journal of Orthopedics》 2026年第1期57-66,共10页
BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges f... BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges from nonoperative methods to surgical interventions such as intramedullary K-wires,which promote faster rehabilitation and improved elbow mobility.AIM To evaluate the outcomes of managing humeral shaft fractures using closed reduction and internal fixation with flexible intramedullary K-wires.METHODS This was a retrospective cohort study analyzing the medical records of patients with humeral shaft fractures managed with flexible intramedullary K-wires at King Abdulaziz Medical City,using non-random sampling and descriptive analysis for outcome evaluation.RESULTS This study assessed the clinical outcomes of 20 patients treated for humeral shaft fractures with intramedullary K-wires.Patients were predominantly male(n=16,80%),had an average age of 39.2 years,and a mean body mass index of 29.5 kg/m2.The fractures most frequently occurred in the middle third of the humerus(n=14,70%),with oblique fractures being the most common type(n=7,35%).All surgeries used general anesthesia and a posterior approach,with no intraoperative complications reported.Postoperatively,all patients achieved clinical and radiological union(n=20,100%),and the majority(n=13,65%)reached an elbow range of motion from 0 to 150 degrees.CONCLUSION These results suggest that intramedullary K-wire fixation may be an effective option for treating humeral shaft fractures,with favorable outcomes in range of motion recovery,fracture union,and a low rate of intraoperative complications. 展开更多
关键词 Humeral shaft fractures Flexible intramedullary K-wires Clinical outcomes Range of motion Surgical management
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Seasonal effects on groundwater fluoride and evaluating health hazards: In-situ remediation via managed aquifer recharge 认领 引用
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作者 D.Karunanidhi Meera Rajan +1 位作者 Priyadarsi D.Roy T.Subramani 《Geoscience Frontiers》 SCIE CAS CSCD 2025年第5期123-138,共16页
This research examines the hard-rock aquifer system within the Nagavathi River Basin(NRB)South India,by evaluating seasonal fluctuations in groundwater composition during the pre-monsoon(PRM)and post-monsoon(POM)perio... This research examines the hard-rock aquifer system within the Nagavathi River Basin(NRB)South India,by evaluating seasonal fluctuations in groundwater composition during the pre-monsoon(PRM)and post-monsoon(POM)periods.Seasonal variations significantly influence the groundwater quality,particularly fluoride(F−)concentrations,which can fluctuate due to changes in recharge,evaporation,and anthropogenic activities.This study assesses the dynamics of F−levels in PRM and POM seasons,and identifies elevated health risks using USEPA guidelines and Monte Carlo Simulations(MCS).Groundwater in the study area exhibits alkaline pH,with NaCl and Ca-Na-HCO3 facies increasing in the POM season due to intensified ion exchange and rock-water interactions,as indicated in Piper and Gibb’s diagrams.Correlation and dendrogram analyses indicate that F−contamination is from geogenic and anthropogenic sources.F−levels exceed the WHO limit(1.5 mg/L)in 51 PRM and 28 POM samples,affecting 371.74 km2 and 203.05 km2,respectively.Geochemical processes,including mineral weathering,cation exchange,evaporation,and dilution,are identified through CAI I&II.Health risk assessments reveal that HQ values>1 in 78%of children,73%of teens,and 68%of adults during PRM,decreasing to 45%,40%,and 38%,respectively,in POM.MCS show maximum HQ values of 5.67(PRM)and 4.73(POM)in children,with all age groups facing significant risks from fluoride ingestion.Managed Aquifer Recharge(MAR)is recommended in this study to minimize F−contamination,ensuring safe drinking water for the community. 展开更多
关键词 Fluoride Seasonal fluctuations Geochemical processes Geogenic sources Managed aquifer recharge
A review of factors affecting the performance and impact of managed aquifer recharge projects:Insights from arid regions 认领 引用
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作者 Ali Al-Maktoumi 《Journal of Groundwater Science and Engineering》 2025年第3期312-340,共29页
Managed Aquifer Recharge(MAR)is a strategic approach to artificially replenishing groundwater supplies and has become an integral component of global water resource management.The number of MAR projects has steadily i... Managed Aquifer Recharge(MAR)is a strategic approach to artificially replenishing groundwater supplies and has become an integral component of global water resource management.The number of MAR projects has steadily increased in recent decades,yet many have failed to achieved their intended outcomes,underscoring the complexity of project implementation.This review is dedicated to examine existing research and reports on MAR performance and impacts,aiming to establish objective criteria for gauging the success and identify key factors influencing the effectiveness of MAR project.Five critical performance factors have been identified as major determinants of MAR performance:aquifer transmissivity,vertical permeability,availability of recharge water,recharge water quality,and aquifer thickness,geometry and boundary conditions.These factors are directly related to project success and significantly shape MAR outcomes.In addition,this review explores research-based strategies to improve MAR success,including cutting-edge methodologies,technological innovations,and integrated management approaches to address key challenges.The ultimate goal is to foster more efficient,effective,and sustainable MAR practices,thereby enhancing the resilience and sustainability of water resource management. 展开更多
关键词 Groundwater Management Artificial Recharge Permeability and Clogging Climate Change Adaptation Flow Dynamics
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A dynamic managed pressure well-control method for rapid treatment of gas kick in deepwater managed pressure drilling 认领 引用 被引量：7
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作者 Hong-Wei Yang Jun Li +4 位作者 Ji-Wei Jiang Hui Zhang Bo-Yun Guo Geng Zhang Wang Chen 《Petroleum Science》 SCIE CAS CSCD 2022年第5期2297-2313,共17页
During deepwater managed pressure drilling(MPD),the gas kick may occur in abnormally high-pressure formations.If the traditional well control method is adopted,the treatment time is long and the advantage of early gas... During deepwater managed pressure drilling(MPD),the gas kick may occur in abnormally high-pressure formations.If the traditional well control method is adopted,the treatment time is long and the advantage of early gas kick detection of MPD is lost.The dynamic managed pressure well-control(MPWC)method can be used to rapidly treat gas kick in deepwater MPD.In this paper,considering the effect of large-variable-diameter annulus and complex wellbore temperature in deepwater drilling,a simplified model of non-isothermal gas-liquid two-phase flow was established for dynamic deepwater MPWC simulation.Using this model,the response characteristics of outlet flow and wellhead backpressure were investigated.The results indicated that the gas fraction,outlet liquid flow rate,pit gain and wellhead backpressure presented complex alternating characteristics when gas moved upwards in the wellbore due to the large-variable-diameter annulus.The outlet liquid flow rate would be lower than the inlet flow rate and the pit gain would decrease before the gas moved to the wellhead.The variation trend of the wellhead backpressure was consistent with that of the pit gain.When the gas-liquid mixture passed through the choke,the expansion or compression of the gas caused part of the choke pressure drop to be supplemented or unloaded,delaying the response rate of the wellhead backpressure.The wellbore temperature,borehole diameter and seawater depth had different effects on outlet flow rate,pit gain and wellhead backpressure.This research could provide a new idea for well control methods in deepwater managed pressure drilling. 展开更多
关键词 Gas kick Managed pressure well-control Gas-liquid two-phase flow Wellhead backpressure Outlet flow characteristics Deepwater managed pressure drilling
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Biodiversity in primary vs.managed forests:Biological legacies of old living and large dead trees drive lichen diversity 认领 引用
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作者 Daniela Dúhová Jeňýk Hofmeister +13 位作者 Garrett W.Meigs Josef Halda Daniel Kozák Matej Ferenčík Rhiannon Gloor Katarína Markuljaková Jakob Pavlin Ivo Pardus Audrey R.Salerno Michal Frankovič Pavel Janda Martin Dušátko Miroslav Svoboda Martin Mikoláš 《Forest Ecosystems》 SCIE CAS CSCD 2025年第6期1178-1189,共12页
Anthropogenic activities have significantly contributed to the loss and fragmentation of primary forests across the globe,which has accelerated biodiversity decline,particularly among highly specialised species depend... Anthropogenic activities have significantly contributed to the loss and fragmentation of primary forests across the globe,which has accelerated biodiversity decline,particularly among highly specialised species dependent on unique forest structures.Nevertheless,comparative studies between primary and managed forests are scarce,despite their importance for effective monitoring and conservation planning.To address this knowledge gap,we conducted a comparative study using a unique dataset of permanent study plots established across some of the best-preserved,mixed-beech primary forests and their adjacent managed counterparts in the Western Carpathian Mountains.We assessed the effects of forest structure and tree age—determined through extensive dendrochronological reconstructions—on contemporary lichen communities.Lichen species richness and the richness of red-listed species were 26%and 50%higher in primary forests than in managed forests,respectively,highlighting the outstanding conservation importance of primary forests.Generalised least squares(GLS)modelling demonstrated that in managed forests,lichen species richness was strongly associated with structural attributes:It increased with maximum tree age and the diameter of standing deadwood,and decreased with higher basal area(BA)of living trees,likely due to reduced understory light.In contrast,no structural variables significantly explained richness in primary forests,likely due to structural saturation and widespread microhabitat availability.Elevation emerged as the sole variable with significant explanatory strength.These findings underscore the critical role of structural complexity in supporting lichen diversity under different management regimes and provide a robust evidence base for promoting elements such as old trees,deadwood—especially large standing deadwood—and reduced canopy density.At the same time,they reaffirm the irreplaceable value of primary forests as biodiversity refuges and highlight the need for landscape-level conservation strategies that integrate both intact primary and structurally enriched managed forests. 展开更多
关键词 Species richness Biodiversity conservation Forest management Forest structure Deadwood Old-growth forest
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Propagation velocity and time laws of backpressure wave in the wellbore during managed pressure drilling 认领 引用
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作者 Yan Tie Qu Junbo +2 位作者 Sun Xiaofeng Chen Ye Pan Yi 《Natural Gas Industry B》 2018年第3期253-260,共8页
When gas invasion,especially overflow,occurs at the bottom hole in the process of managed pressure drilling(MPD),it is common to apply backpressure on the wellbore by adjusting the backpressure pump and throttle valve... When gas invasion,especially overflow,occurs at the bottom hole in the process of managed pressure drilling(MPD),it is common to apply backpressure on the wellbore by adjusting the backpressure pump and throttle valve,so as to rebuild bottom hole pressure balance.If it is still thought that the wellhead backpressure is loaded to the bottom hole instantaneously,there will be larger errors between the calculated wellbore parameters and the actual wellbore flow parameters,which will result in well control failure and even well blowout.In this paper,a pressure wave propagation equation suitable for the gaseliquid two-phase flow in the annulus was established based on the global averaged gaseliquid two-phase flow model to investigate the propagation velocity and time of backpressure wave in the wellbore.Then,gaseliquid interaction was introduced to carry out coupling solution on the equation set.It is shown that pressure wave velocity increases with the increase of drilling mud density,but decreases with the increase of void fraction and virtual mass force coefficient.It changes drastically at first,and then slows down.What's more,when the void fraction is greater than 0.1 or the virtual mass force coefficient exceeds 0.2,the momentum between gas phase and liquid phase is fully exchanged,and the pressure wave velocity decreases slowly,approaching a stable value.In Well Penglai 9 in the Sichuan Basin,for example,the average time of single pressure wave propagation is about 50 s,and the total propagation time of 4 rounds is about 200 s,which accounts for more than 67%of the total time of system control response.It is indicated that the propagation velocity and time of the pressure wave in the annulus calculated by this method can greatly improve the accuracy of managed pressure response time of MPD drilling system and the control precision of adaptive throttle valve. 展开更多
关键词 Managed pressure drilling(MPD) Gas invasion Gaseliquid two-phase flow model Virtual mass force coefficient Gaseliquid two-phase flow Pressure wave propagation equation Pressure wave velocity Managed response time
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Vendor managed inventory and bullwhip effect 认领 引用 被引量：5
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作者 张钦 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期108-112,共5页
This paper studies that the bullwhip effect of order releases and the amplifications of safety stock arise within the supply chain even when the demand model is ARIMA(0, 1, 1) and the forecast method used is a simple ... This paper studies that the bullwhip effect of order releases and the amplifications of safety stock arise within the supply chain even when the demand model is ARIMA(0, 1, 1) and the forecast method used is a simple exponentially weighted moving average. It also examines a vendor managed inventory (VMI) program to determine how it can help alleviate such negative effects, and gives the theoretical proofs and numerical illustrations. The results show that the effects with VMI are better than the effect without VMI in demand forecasting and safety stock levels, etc. 展开更多
关键词 vendor managed inventory bullwhip effect supply chain demand forecasting
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Application of fine managed pressure drilling technique in complex wells with both blowout and lost circulation risks 认领 引用 被引量：2
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作者 Yan Ling Wu Huisheng Yan Yan 《Natural Gas Industry B》 2015年第2期192-197,共6页
Fractured carbonate reservoirs are susceptible to blowout and lost circulation during drilling,which not only restricts drilling speed,but also poses big threat to well control.Moreover,there are few technical means a... Fractured carbonate reservoirs are susceptible to blowout and lost circulation during drilling,which not only restricts drilling speed,but also poses big threat to well control.Moreover,there are few technical means available to reconstruct pressure balance in the borehole.Accordingly,the fine managed pressure drilling was used in the drilling of Well GS19 in the Qixia Formation with super-high pressure and narrow density window,which is a success:①back pressure in the annular spaces will be adjusted to maintain a slightly over-balanced bottom-hole hydraulic pressure,and fluid level in the circulation tank will be kept in a slight dropping state to ensure that natural gas in the formation would not invade into the borehole in a massive volume;②inlet drilling fluid density will be controlled at around 2.35 g/cm3,back pressures in the annular be maintained at 2-5 MPa,and bottom-hole pressure equivalent circulation density be controlled at 2.46-2.52 g/cm3;③during managed pressure drilling operations,if wellhead pressure exceeds or expects to exceed 7 MPa,semi-blind rams will be closed.Fluids will pass through the choke manifold of the rig to the choke manifold specifically for pressure control before entering gas/liquid separators to discharge gas;④during tripping back pressure will be kept at less than 5 MPa,volume of injected drilling fluid will be higher than the theoretical volume during tripping out,whereas the volume of returned drilling fluid will be higher than the theoretical volume during the out-tripping.This technique has been applied successfully in the drilling of the Qixia Formation,Liangshan Formation and Longmaxi Formation with a total footage of 216.60 m,as a good attempt in complicated wells with both blowout and lost circulation risks,which can provide valuable experiences and guidance for handling similar complexities in the future. 展开更多
关键词 Sichuan Basin Carbonate rocks Overflow Lost circulation Co-existence of blowout and lost circulation Multi-pressure system Fine managed pressure Narrow density window
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Managed grassland alters soil N dynamics and N2O emissions in temperate steppe 认领 引用 被引量：3
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作者 Lijun Xu Xingliang Xu +7 位作者 Xuejuan Tang Xiaoping Xin Liming Ye Guixia Yang Huajun Tang Shijie Lv Dawei Xu Zhao Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期20-30,共11页
Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen（N） dynamics and nitrous oxide（N2O） emissions. However, it ... Reclamation of degraded grasslands as managed grasslands has been increasingly accelerated in recent years in China. Land use change affects soil nitrogen（N） dynamics and nitrous oxide（N2O） emissions. However, it remains unclear how large-scale grassland reclamation will impact the grassland ecosystem as a whole. Here, we investigated the effects of the conversion from native to managed grasslands on soil N dynamics and N2O emissions by field experiments in Hulunber in northern China. Soil（0-10 cm）, nitrate（NO3-）,ammonium（NH4＋）, and microbial N were measured in plots in a temperate steppe（Leymus chinensis grassland） and two managed grasslands（Medicago sativa and Bromus inermis grasslands） in 2011 and 2012. The results showed conversion of L. chinensis grassland to M.sativa or B. inermis grasslands decreased concentrations of NO3--N, but did not change NH4-N . Soil microbial N was slightly decreased by the conversion of L. chinensis grassland to M.sativa, but increased by the conversion to B. inermis. The conversion of L. chinensis grassland to M. sativa（i.e., a legume grass） increased N2O emissions by 26.2%, while the conversion to the B. inermis（i.e., a non-legume grass） reduced N2O emissions by 33.1%. The conversion from native to managed grasslands caused large created variations in soil NO3-＋-N and NH4-N concentrations. Net N mineralization rates did not change significantly in growing season or vegetation type, but to net nitrification rate. These results provide evidence on how reclamation may impact the grassland ecosystem in terms of N dynamics and N2O emissions. 展开更多
关键词 Temperate steppe Managed grassland Land use Nitrogen mobility N2O emissions
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基于Managed DirectX的三维建模器的开发与研究 认领 引用 被引量：1
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作者 杨建鸣 王鹏飞 边明杰 《中国制造业信息化（学术版）》 2007年第6期45-47,共3页
针对目前.NET技术应用范围的不断扩大,通过.NET构架,充分利用.NET的快速开发能力,开发了基于Managed DirectX的三维建模器,作为下一步基于三维建模器的虚拟产品技术的基础和平台,在此系统的开发过程中研究了Managed DirectX的开发技术... 针对目前.NET技术应用范围的不断扩大,通过.NET构架,充分利用.NET的快速开发能力,开发了基于Managed DirectX的三维建模器,作为下一步基于三维建模器的虚拟产品技术的基础和平台,在此系统的开发过程中研究了Managed DirectX的开发技术及相关三维图形算法。 展开更多
关键词 Managed DirectX .NET 三维建模器
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U.S.Academic Medical Centers Under the Managed Health Care Environment 认领 引用 被引量：1
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作者 KRISTINA GUO 《Biomedical and Environmental Sciences》 SCIE CAS 1999年第2期81-87,共7页
This research investigates the impact of managed health care on academic medical centers in the United States.Academic medical centers hold a unique position in the U.S.health care system through their missions of con... This research investigates the impact of managed health care on academic medical centers in the United States.Academic medical centers hold a unique position in the U.S.health care system through their missions of conducting cutting-edge biomedical researeh,pursuing clinical and technological innovations,Providing state-of-the-art medical care and producing highly qUalified health professionals.However,policies to control costs through the use of managed care and limiting resources are detrimental to academic medical centers and impede the advancement of medical sciTo survive the threats of managed care in the health care environment,acadendc medical centers must rely on their upper level managers to derive successful strategies.The methods used in this study include qualitative approaches in the form of key informants and case studies.In addition,a survey questionnaire was sent to 1h8 CEOs in all the academic medical centers in the U.S.The findings revealed that managers who perform the liaison,monitor,entrepreneur and resource allocator roles are crucial to ensure the survival of academic medical centers,so that academic medical centers can continue their missions to serve the general public and promote their well-being. 展开更多
关键词 Academic Medical Centers Cost Control Health Policy Humans Managed Care Programs Organizational Innovation United States
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Design and application of well cementing technology based on the precise managed pressure balancing method in narrow pressure window hole sections 认领 引用
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作者 Guo Jianhua Zheng Youcheng +3 位作者 Li Wei Li Bin Yuan Bin Xu Bihua 《Natural Gas Industry B》 2020年第3期285-291,共7页
In the Sichuan Basin,the drilling of complex deep and ultradeep wells is restricted by the casing sequence.Multiple pressure systems are usually encountered in the same open hole section,and narrow safety density wind... In the Sichuan Basin,the drilling of complex deep and ultradeep wells is restricted by the casing sequence.Multiple pressure systems are usually encountered in the same open hole section,and narrow safety density window is observed in vertical strata.The application of managed pressure drilling(MPD)technique which is often used in well drilling ensures the safe and efficient drilling,but it also brings about great challenges to the small-gap liner cementing at the lower part.Therefore,it is of great practical significance to research a cementing technology that can not only satisfy the quality requirement of small gap liner cementing,but also ensure the safe cementing in the strata with narrow safety density window.In this paper,a cementing technology based on precise managed pressure balancing method was proposed by referring to the successful application of MPD technique.According to the cementing design,the hydrostatic column pressure of annulusfluid is under-balanced(slightly lower than the formation pore pressure),and then a precise managed pressure drilling device is adopted to produce back pressure through wellhead restriction or apply wellhead compensation pressure,so that the balanced pore pressure can be reached in the process of cementing via the wellhead pressure and theflow friction offluid in the annulus.After the cementing is completed,a certain compensation pressure is applied to the annulus continuously to prevent annulus channeling during waiting on cement caused by insufficient static pressure and slurry weight loss.After this technology was applied to an ultradeep exploration well in the Sichuan Basin,the qualification rate of borehole cementing quality reached 97%,and the well sections with good cementing quality accounted for 76%.In conclusion,this technology needs no additional equipment,and only by virtue of the MPD equipment,it can achieve safe cementing construction and cementing quality improvement under high displacement efficiency. 展开更多
关键词 Narrow safety density window Precise managed pressure Liner Cementing Lost cireulation Pressure balancing chuan basin
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Managed DirectX三维建模技术中的类实现 认领 引用
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作者 邢静宜 王鹏飞 +1 位作者 谭小峰 顾瑞春 《计算机技术与发展》 2007年第4期208-210,共3页
三维建模技术是进行三维仿真的基础,使用高级语言和图形接口进行三维建模的开发是根本的解决方法。针对目前.NET技术的快速发展与应用,采用.NET语言和Managed DirectX技术进行开发,对基于Managed DirectX的三维建模技术中的三维模型类... 三维建模技术是进行三维仿真的基础,使用高级语言和图形接口进行三维建模的开发是根本的解决方法。针对目前.NET技术的快速发展与应用,采用.NET语言和Managed DirectX技术进行开发,对基于Managed DirectX的三维建模技术中的三维模型类进行了研究及实现,并在.NET环境下开发了三维模型基类库,其中使用了参数化建模方法。最终实现了基本的三维建模类,在此基础上可进一步开发出通用的三维建模器。Managed DirectX作为DirectX中重要的成员,为基于.NET框架开发三维图形应用程序提供了极大的方便。 展开更多
关键词 Managed DirectX .NET 三维建模 类实现
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Methods of vendor managed inventory control in supply chain management 认领 引用 被引量：8
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作者 蒋振盈 于海生 +1 位作者 彭禄斌 赵林度 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期405-409,共5页
By inducing the typical inventory control problem - the bullwhip effect, this paper presents vendor managed inventory (VMI) control methods on the basis of traditional methods of inventory management methods, construc... By inducing the typical inventory control problem - the bullwhip effect, this paper presents vendor managed inventory (VMI) control methods on the basis of traditional methods of inventory management methods, constructs a VMI mathematics model, and analyzes the influence of VMI on inventory cost and channel profit. Finally, a special case is studied to verify that VMI is an effective supply chain strategy that can not only increase channel profit of supplier and customer but also improve full channel coordination, thereby reducing the bullwhip effect. 展开更多
关键词 supply chain management inventory control vendor managed inventory bullwhip effect
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Coarse woody debris and wood-colonizing fungi differences between a reserve stand and a managed forest in the Taborz region of Poland 认领 引用 被引量：3
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作者 Slwomir Pieeka Agata Sotnik +1 位作者 Marta Damszel Zbigniew Sierota 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期1081-1091,共11页
The aim of this research was to evaluate the amount of woody debris (m3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenan... The aim of this research was to evaluate the amount of woody debris (m3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenance experiments, against the background of a recently launched Polish legislation to protect the biodiversity on the forest floor in managed (harvested) stands. We investigated a managed stand (136-years-old) and the reserve stand ‘Sosna Taborska’(261-years-old). In the reserve stand, the mean volume of woody debris was six times higher than in the managed forests, i.e. 65 versus 11 m3/ha. In addition, in the reserve stand, the number of fungi taxa colonizing the dead wood was larger than in the managed stands, with a higher number of fruitbodies. Total fungal richness was higher in the reserve than in the managed stand, i.e. 28 versus 12 species. The dominant taxa at both sites were Fomitopsis pinicola and Fomes The aim of this research was to evaluate the amount of woody debris (m^3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenance experiments, against the background of a recently launched Polish legislation to protect the biodiversity on the forest floor in managed (harvested) stands. We investigated a managed stand (136-years-old) and the reserve stand ‘Sosna Taborska’(261-years-old). In the reserve stand, the mean volume of woody debris was six times higher than in the managed forests, i.e. 65 versus 11 m^3/ha. In addition, in the reserve stand, the number of fungi taxa colonizing the dead wood was larger than in the managed stands, with a higher number of fruitbodies. Total fungal richness was higher in the reserve than in the managed stand, i.e. 28 versus 12 species. The dominant taxa at both sites were Fomitopsis pinicola and Fomes fomentarius, although some taxa were only found in the reserve (e.g., Stereum hirsutum). The volume of woody debris as well as the diversity of fungi in the managed stand were lower than in the reserve, albeit greater than in other Scots pine stands in Poland. These results testify to the gains in biodiversity yielded by the management conservation management approach at the reserve stand. 展开更多
关键词 Coarse woody debris Fungi Managed (harvested) stands Reserve Sosna Taborska Reserve Forest Indices
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Managed aquifer recharge(MAR)applications in China–achievements and challenges 认领 引用 被引量：2
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作者 Jin-xing Guo Zhi-ping Li Catalin Stefan 《Journal of Groundwater Science and Engineering》 2022年第1期57-69,共13页
Groundwater is of fundamental significance for human society,especially in semi-arid areas in China.However,due to the fast social and economic development,China has been suffering from the shortage of water resource.... Groundwater is of fundamental significance for human society,especially in semi-arid areas in China.However,due to the fast social and economic development,China has been suffering from the shortage of water resource.In this situation,managed aquifer recharge(MAR)was considered to be an effective measure for the sustainable management of groundwater resources.Since 1960 s,China successfully implemented many MAR schemes for different purposes such as restoration of groundwater tables,prevention of seawater intrusion,increasing urban water supplies and controlling land subsidence.From those successful experiences China developed a scientific and applicable system to implement MAR project.However,there were still many challenges in this field,for example,treated waste water had been barely used for recharge.The present review summarized the achievements in MAR applications in China as well as the associated challenges within the past 55 years before the year 2016. 展开更多
关键词 Managed aquifer recharge(MAR) Groundwater Recharge Aquifer Storage
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National Forest Inventories capture the multifunctionality of managed forests in Germany 认领 引用 被引量：4
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作者 Nadja K.Simons María R.Felipe-Lucia +26 位作者 Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser 《Forest Ecosystems》 SCIE CSCD 2021年第1期50-68,共19页
Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forest... Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.g.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.g.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.g.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.g.phosphorous availability or cover of edible plants)or tree species composition(e.g.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level,when stands of complementary forest types are combined.These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales. 展开更多
关键词 Ecosystem processes and services Forest management Structural diversity Tree species composition Trade-offs and synergies Forest productivity
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Giant idiopathic renal arteriovenous fistula managed by coils and amplatzer device:Case report and literature review 认领 引用 被引量：3
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作者 Prashant Nagpal Girish Bathla +4 位作者 Sachin S Saboo Ashish Khandelwal Abhishek Goyal Frank J Rybicki Michael L Steigner 《World Journal of Clinical Cases》 SCIE 2016年第11期364-368,共5页
An idiopathic renal arteriovenous(AV) fistula is a rare malformation of the kidney that may present insidiously with heart failure or hematuria.The treatment may be challenging due to large fistula size that may limit... An idiopathic renal arteriovenous(AV) fistula is a rare malformation of the kidney that may present insidiously with heart failure or hematuria.The treatment may be challenging due to large fistula size that may limit endovascular management.The authors report a case of an 85-year-old Caucasian woman who presented with acute heart failure and was found to have a right renal AV fistula.Since she had no prior history of renal intervention or trauma,a diagnosis of idiopathic renal AV fistula was made.She was managed by endoluminal occlusion using multiple stainless steel coils and Amplatzer vascular plug II device.The follow-up computed tomography showed complete occlusion of the fistula.This report highlights the late presentation of this rare disease and presents the utility of the combination of coils and Amplatzer device for management of a large fistula.It also reiterates that even if large,these fistulas can be managed by endovascular occlusion. 展开更多
关键词 Heart failure Idiopathic Arteriovenous fistula Endovascular management Amplatzer device
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Hydrological and economic feasibility of mitigating a stressed coastal aquifer using managed aquifer recharge: a case study of Jamma aquifer, Oman 认领 引用
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作者 Mustafa EL-RAWY Ali AL-MAKTOUMI +2 位作者 Slim ZEKRI Osman ABDALLA Rashid AL-ABRI 《Journal of Arid Land》 SCIE CSCD 2019年第1期148-159,共12页
This study explored the hydrological and economic feasibility of managed aquifer recharge(MAR) using tertiary treated wastewater(TWW) to mitigate salinity in the coastal aquifer of Jamma, Oman. A steady-state groundwa... This study explored the hydrological and economic feasibility of managed aquifer recharge(MAR) using tertiary treated wastewater(TWW) to mitigate salinity in the coastal aquifer of Jamma, Oman. A steady-state groundwater flow and transport model, using MODFLOW software, was developed and calibrated. Different managerial scenarios were simulated and the results reveal that the Jamma aquifer will be further deteriorated in the next 20 a if it remains unmanaged. The groundwater table will decline further by more than 3 m on average; and the iso-concentration salinity line of 1500 mg/L will advance 2.7 km inland, which will severely affect the farming activities in the area. However, MAR using TWW when integrated with the management of groundwater abstraction(e.g., using modern irrigation systems to reduce the abstraction rate) becomes hydrologically feasible to augment the aquifer storage and control seawater intrusion, and hence improves the farming activities. The results indicate that:(1) injecting TWW in the vicinity of irrigation wells(Scenario A2);(2) investing in smart water meters and online control of pumping from the wells to reduce the abstraction rate by 25%(Scenario B); and(3) a combination of both(Scenario B2) are feasible scenarios with positive net present values. Recharge in upstream areas is found not economically feasible because of the very high investment cost of the installation of pipes to transport the TWW over a distance of 12.5 km. Because of securing funds are challenging, Scenario B would be the best option and the second-best option is Scenario A2. Scenario B2 has the lowest net benefit investment ratio and is very attractive because it entails integrated demand and supply management of groundwater. It is required to reduce pumping and to invest in injecting TWW to improve groundwater quality in the vicinity of irrigation wells and to form a hydrological barrier to control seawater intrusion in the long run. 展开更多
关键词 managed aquifer recharge treated wastewater salinity line coastal aquifer Oman
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