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Performance Evaluation of Two Series Vertical Flow Filters for Wastewater Treatment: A Case Study of the Prototype Installed at Gaston Berger University, Saint-Louis, Senegal
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作者 Abdou Khafor Ndiaye Falilou Coundoul +2 位作者 Abdoulaye Deme Antonina Torrens Armengol Abdoulaye Senghor 《Open Journal of Modern Hydrology》 CAS 2024年第1期14-32,共19页
This paper evaluates the efficacy of two sequential vertical flow filters (VFF), FV1 and FV2, implanted with Typha, in a pilot-scale wastewater treatment system. FV1 comprises three cells (FV1a, FV1b, and FV1c), while... This paper evaluates the efficacy of two sequential vertical flow filters (VFF), FV1 and FV2, implanted with Typha, in a pilot-scale wastewater treatment system. FV1 comprises three cells (FV1a, FV1b, and FV1c), while FV2 consists of two cells (FV2a and FV2b), each designed to reduce various physicochemical and microbiological pollutants from wastewater. Quantitative analyses show significant reductions in electrical conductivity (from 1331 to 1061 μS/cm), biochemical oxygen demand (BOD5 from 655.6 to 2.3 mg/L), chemical oxygen demand (COD from 1240 to 82.2 mg/L), total nitrogen (from 188 to 37.3 mg/L), and phosphates (from 70.9 to 14.6 mg/L). Notably, FV2 outperforms FV1, particularly in decreasing dissolved salts and BOD5 to remarkably low levels. Microbiological assessments reveal a substantial reduction in fecal coliforms, from an initial concentration of 7.5 log CFU/100mL to 3.7 log CFU/100mL, and a complete elimination of helminth eggs, achieving a 100% reduction rate in FV2. The study highlights the impact of design parameters, such as filter material, media depth, and plant species selection, on treatment outcomes. The findings suggest that the judicious choice of these components is critical for optimizing pollutant removal. For instance, different filtration materials show varying efficacies, with silex plus river gravel in FV1c achieving superior pollutant reduction rates. In conclusion, VFFs emerge as a promising solution for wastewater treatment, underscoring the importance of design optimization to enhance system efficiency. Continuous monitoring and adaptation of treatment practices are imperative to ensure water quality, allowing for safe environmental discharge or water reuse. The research advocates for ongoing improvements in wastewater treatment technologies, considering the environmental challenges of the current era. The study concludes with a call for further research to maximize the effectiveness of VFFs in water management. 展开更多
关键词 PHYTOREMEDIATION Phytopurification Plant-Based Purifier Wastewater Treat-ment Vertical Flow Filters Pollutant Reduction TYPHA Physicochemical Analysis Microbial Removal
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Quantification of In Vivo Epidermal Keratinocyte Architecture Associated with the Signs of Skin Aging and the Skin Benefit Evaluation by Application of Galactomyces Ferment Filtrate (Pitera)-Containing Skin Care Product
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作者 Kukizo Miyamoto Yoko Munakata +4 位作者 Keisuke Fujii Chenlu Lei Ley Yang Suda Sudarsana Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第1期12-28,共17页
Background: Aged skin exhibits visual alterations such as wrinkles, rough texture, pore dilation, and dull skin tone, as well as physiological aging, namely, decreased hydration and increased transepidermal water loss... Background: Aged skin exhibits visual alterations such as wrinkles, rough texture, pore dilation, and dull skin tone, as well as physiological aging, namely, decreased hydration and increased transepidermal water loss (TEWL). Recent advances in coherence tomography have also revealed that skin aging affects in vivo epidermal keratinocyte architecture. However, the interconnectivity between spatial architectural aging and visual/physiological aging parameters remains largely unknown. Purpose: To elucidate whether the tomographic keratinocyte architectural aging is correlated with visual and physiological skin aging parameters and to quantitatively evaluate the improvements of the architectural, visual, and physiological aging parameters by the daily treatment of the skin care formula containing Galactomyces Ferment Filtrate (GFF, 8X Pitera<sup>TM</sup>). Method: We measured the in vivo keratinocyte cellular architecture with two-photon stereoscopic tomography obtaining by-layer epidermal section images in 78 Asian females of various ages. Visual aging parameters were analyzed using a portable image capture system. Hydration and TEWL were also assessed. The anti-aging effects of GFF-containing skin moisturizer (SK-II LXP Cream<sup>TM</sup>) were also examined in two studies after twice-daily application for 2 (N = 35) and 4 (N = 32) weeks. Results: As for the keratinocyte cellular architecture, skin aging was significantly associated with decreased cell density and increased cell uniformity. These architectural aging parameters were significantly correlated with visual and physiological aging parameters, namely, rough texture, wrinkles, pore dilation, dull skin tone, dehydration, and increased TEWL. The strong interconnectivity allowed us to develop formulae to estimate the keratinocyte architecture from visual aging parameters. Moreover, twice-daily application of SK-II significantly improved the keratinocyte architecture associated with multiple skin aging visual and physiological parameters. Conclusion: Skin aging is a process involving mutual interconnections among epidermal keratinocyte cellular architecture, visual, and physiological parameters. The GFF-containing moisturizer SK-II effectively improves spatial architecture of keratinocytes in epidermis and these evaluated skin aging parameters in a new trajectory over the course of treatment. . 展开更多
关键词 Facial Skin Aging In Vivo Keratinocyte Cellular Architecture Visual Aging Pa-rameter Dehydration INTERCONNECTIVITY New Trajectory Galactomyces Fer-ment Filtrate PiteraTM SK-II LXP CreamTM
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归一化Alignment距离 被引量:1
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作者 卢国祥 《工程数学学报》 CSCD 北大核心 2014年第1期1-8,共8页
为了更好地度量不同序列之间的差异,本文在给定度量空间上的符号距离满足特定条件的前提下,以Alignment距离为基础,提出了一种归一化Alignment距离.接下来利用Alignment相关度证明了该距离满足度量定义的三个条件,并且取值在[0,1]区间上... 为了更好地度量不同序列之间的差异,本文在给定度量空间上的符号距离满足特定条件的前提下,以Alignment距离为基础,提出了一种归一化Alignment距离.接下来利用Alignment相关度证明了该距离满足度量定义的三个条件,并且取值在[0,1]区间上.最后对其进行了进一步讨论,从理论上说明该定义的合理性.该距离可以在序列比对、聚类分析以及模式识别等领域中发挥重要作用. 展开更多
关键词 Alignment距离 Alignment相关度 归一化距离 归一化Alignment距离 三角不等式
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Mente-Carlo方法在热交换器传热管降质评估中的应用
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作者 韩冬傲 丁志伟 +1 位作者 金刚 浦承皓 《汽轮机技术》 北大核心 2023年第4期309-313,共5页
结合EPRI的无损检测数据,对无损检验的不确定度和传热管降质增长量进行Mente-Carlo模拟,建立了一种简便有效的传热管完整性评估方法。通过该方法计算了某电站某型热交换器传热管堵管限值,当传热管整体降质超过38%TW或者38%PDA时,应该对... 结合EPRI的无损检测数据,对无损检验的不确定度和传热管降质增长量进行Mente-Carlo模拟,建立了一种简便有效的传热管完整性评估方法。通过该方法计算了某电站某型热交换器传热管堵管限值,当传热管整体降质超过38%TW或者38%PDA时,应该对传热管进行维修或堵管。建立的计算传热管完整性评估方法,可根据具体设备的特定工况进行分析计算,制定堵管维修准则,避免了热交换器运行管理过程中太过保守或裕量不足的风险,具有较高的可信度,提升了热交换器运行经济价值。 展开更多
关键词 传热管堵管 完整性评估 蒙特卡洛模拟 维修限值
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Anomalous crustal movements before great Wenchuan earthquake observed by GPS 被引量:10
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作者 Gu Guohua Meng Guojie Wang Wuxing 《Geodesy and Geodynamics》 2011年第2期13-22,共10页
Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sess... Studies of GPS data carried out before and after the great Wenchuan earthquake of Ms8.0 on May 12, 2008 show that anomalous crustal movements occurred before the earthquake. Data from 4 pre-earthquake observation sessions at a dense network of stations show that there were prominent broad-ranged long- and midterm anomalies in horizontal displacements and strain and in vertical displacements. Data from the fewer-numbered reference stations of continuous GPS observations since 1999 in West and South China showed short-term preseismic anomalies in horizontal displacements. The detection of co-seismic horizontal displacements at these stations supports the existence of the pre-earthquake anomalies. Results of single-epoch solutions of data from continuous-observation stations near the epicenter also show large imminent anomalies in vertical displacements. Although the Wenchuan earthquake was not predicted, these results give a strong indication that GPS should be the main observation technique for long-term, mid-term, short-term and imminent earthquake predictions. 展开更多
关键词 Wenchuan earthquake earthquake prediction GPS crustal movement horizontal displace- ment vertical displacement
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Resource allocation optimization of equipment development task based on MOPSO algorithm 被引量:7
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作者 ZHANG Xilin TAN Yuejin and YANG Zhiwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1132-1143,共12页
Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees ... Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees of uncertainty.This paper presents an investigation into the influence of resource allocation on the duration and cost of sub-tasks.Mathematical models are constructed for the relationships of the resource allocation quantity with the duration and cost of the sub-tasks.By considering the uncertainties,such as fluctuations in the sub-task duration and cost,rework iterations,and random overlaps,the tasks are simulated for various resource allocation schemes.The shortest duration and the minimum cost of the development task are first formulated as the objective function.Based on a multi-objective particle swarm optimization(MOPSO)algorithm,a multi-objective evolutionary algorithm is constructed to optimize the resource allocation scheme for the development task.Finally,an uninhabited aerial vehicle(UAV)is considered as an example of a development task to test the algorithm,and the optimization results of this method are compared with those based on non-dominated sorting genetic algorithm-II(NSGA-II),non-dominated sorting differential evolution(NSDE)and strength pareto evolutionary algorithm-II(SPEA-II).The proposed method is verified for its scientific approach and effectiveness.The case study shows that the optimization of the resource allocation can greatly aid in shortening the duration of the development task and reducing its cost effectively. 展开更多
关键词 resource allocation equipment development task multi-objective particle swarm optimization(MOPSO) develop ment task simulation.
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从“声音”到“supplément”
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作者 方向红 《现代哲学》 CSSCI 北大核心 2002年第4期96-100,108,共6页
“supplemént”(“充替”)是解构理论的重要支柱。本文试图从时间性和符号学理路出发完整地重构德里达从对“声音”的解构向“supplément”原理的过渡。同时本文也力求证明,德里达的这种过渡与对胡塞尔符号理论的挪用、引申... “supplemént”(“充替”)是解构理论的重要支柱。本文试图从时间性和符号学理路出发完整地重构德里达从对“声音”的解构向“supplément”原理的过渡。同时本文也力求证明,德里达的这种过渡与对胡塞尔符号理论的挪用、引申和误读是密不可分的。 展开更多
关键词 声音 supplément 超越 触发
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Environmental Radiation Measurement and Assessment of Natural Radioactivity in Soil, Water and Vegetation 被引量:1
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作者 Nandi-Esom Chariette Ereh Meng Zhang 《Journal of Applied Mathematics and Physics》 2018年第11期2330-2337,共8页
Environmental radioactivity is produced by radioactive materials in the human environment. While some radioisotopes, such as strontium-90 (90Sr) and technetium-99 (99Tc), are only found on Earth as a result of human a... Environmental radioactivity is produced by radioactive materials in the human environment. While some radioisotopes, such as strontium-90 (90Sr) and technetium-99 (99Tc), are only found on Earth as a result of human activity, and some, like potassium-40 (40K), are only present due to natural processes, a few isotopes, e.g. tritium (3H), result from both natural processes and human activities. The concentration and location of some natural isotopes, particularly uranium-238 (238U), can be affected by human activity because of the constant exposure of Human beings to radiation caused by terrestrial, extra-terrestrial and anthropogenic radio nuclides, it is necessary to determine and estimate the activity of various radio nuclides in environmental media such as vegetation, soil, and water. In the present research, the activities of 226Ra, 232Th and 40K are measured in soil, vegetation and water samples, collected from Yangdong District, Yangxi County, and Yangjiang County of Guangdong Province, China using an HPGe based gamma spectrometry system. The measured mean activity of 226Ra, 232Th and 40K in soil samples was found to be 31.19 ± 1.2, 47.00 ± 2.30 and 589.31 ± 17.52 Bqkg-1, respectively. The measured mean activity of these radionuclides in all water samples was found to be below minimum detectable activity. The measured mean activity of 226Ra, 232Th and 40K in vegetation samples was 19.92 ± 3.09, 25.36 ± 8.11 and 4982.94 ± 85.68 Bqkg-1, respectively. No anthropogenic 137Cs was detected in these environmental samples. Mean radium equivalent activity (Raeq), external radiation hazard index (Hex), internal radiation hazard index (Hin) and absorbed dose rate (D) for the area under study were determined as 142.92 Bqkg-1, 0.38, 0.47 and 66.47 nGyh-1, respectively. The annual effective dose equivalent (AEDE) varied in the range from 0.03 to 0.12 mSvy-1. It is concluded that the surveyed area do not pose any significant radiological risk to the population and environment. 展开更多
关键词 High PURITY GERMANIUM Detector RADIUM THORIUM POTASSIUM RADIUM Equivalent Activity Radiation HAZARD Indices and Environment Measure-ment
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2012年庐江县居民主要死因Fulfillment指数分析
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作者 宋红兵 洪光烈 左登敏 《中国农村卫生》 2015年第7期67-67,69,共2页
目的:探讨庐江县2012年不同年龄组人群某死因对居民期望寿命的影响程度。方法:根据Prifhis Das Gupta等提出的Fulfilment指数法,对2012年庐江县居民死因监测资料进行分析。结果:2012年庐江县0岁组人群损伤与中毒和呼吸系统疾病对潜... 目的:探讨庐江县2012年不同年龄组人群某死因对居民期望寿命的影响程度。方法:根据Prifhis Das Gupta等提出的Fulfilment指数法,对2012年庐江县居民死因监测资料进行分析。结果:2012年庐江县0岁组人群损伤与中毒和呼吸系统疾病对潜在寿命的影响最大,其Fulfil ment指数分别为3.73和6.22;1~39岁年龄段去意外死亡的Fulfil ment指数较高;2012年庐江县居民去恶性肿瘤的Fulfil ment指数在40~60岁年龄段较高;脑血管病自35~岁组后Fulfillment指数大致呈现逐年升高趋势。结论:通过运用Fulfillment指数分析,可以说明各种死因对各年龄组段人口寿命的影响程度,提示某死因防治的重点时期,对提高居民寿命有积极作用。 展开更多
关键词 主要死因 Fulfil ment指数分析
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EFFECT OF HEAT-TREATMENT ON THE MECHANICAL PROPERTIES OF AIN/SICw(Y_2O_3+SiO_2)COMPOSITE
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作者 李凝芳 张宏泉 周毅 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1994年第2期15-21,共7页
In the paper, the effect of heat-treatment on the strength and toughness of AIN-SiC whisker composites with Y2O3 + SiO2 additives have been studied. When the Sample confining 10wt% Y2O3+SiO2(.Y2O3/SiO2^l/0. 66) -was t... In the paper, the effect of heat-treatment on the strength and toughness of AIN-SiC whisker composites with Y2O3 + SiO2 additives have been studied. When the Sample confining 10wt% Y2O3+SiO2(.Y2O3/SiO2^l/0. 66) -was treated at 1330癈 in air for 140 hours ithe flexural strength of composites ivas raised from 481 MPa to 784 MPa the toughness ruas also enhanced slightly. The phase composi-tion infrastructure and grain boundary phase structure have been char-acterized by combining XDR, SEM, TEM/EDXA and HREM tech-niques, reinforcenent and toughening mechanism of the composites re-sults from the crystallization of glass phase in the grain boundary at the high temperature oxidizing atmosphere to form the crossing struc-ture of 2H?sialon fibrous phase and SiC whisker 展开更多
关键词 AIN WHISKER COMPOSITE heat-treatment reinforce-ment TOUGHENING
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Enhancing the precision of phase estimation by weak measurement and quantum measurement reversal
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作者 贺志 姚春梅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期232-237,共6页
The enhancement of the precision of phase estimation in quantum metrology is investigated by employing weak measurement (WM) and quantum measurement reversal (QMR). We derive the exact expressions of the optimal q... The enhancement of the precision of phase estimation in quantum metrology is investigated by employing weak measurement (WM) and quantum measurement reversal (QMR). We derive the exact expressions of the optimal quantum Fisher information (QFI) and success probability of phase estimation for an exactly solving model consisting of a qubit interacting with a structured reservoir. We show that the QFI can be obviously enhanced by means of the WM and QMR in different regimes. In addition, we also show that the magnitude of the decoherence involved in the WM and QMR can be a general complex number, which extends the applicable scope of the WM and QMR approach. 展开更多
关键词 precision of phase estimation quantum fisher information weak measurement quantum measure-ment reversal
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MULTI-OBJECTIVE PROGRAMMING FOR AIRPORT GATE REASSIGNMENT
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作者 李军会 陈欣 朱金福 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第2期209-215,共7页
To improve the efficiency of gate reassignment and optimize the plan of gate reassignment,the concept of disruption management is introduced,and a multi-objective programming model for airport gate reassignment is pro... To improve the efficiency of gate reassignment and optimize the plan of gate reassignment,the concept of disruption management is introduced,and a multi-objective programming model for airport gate reassignment is proposed.Considering the interests of passengers and the airport,the model minimizes the total flight delay,the total passengers′walking distance and the number of flights reassigned to other gates different from the planned ones.According to the characteristics of the gate reassignment,the model is simplified.As the multi-objective programming model is hard to reach the optimal solutions simultaneously,a threshold of satisfactory solutions of the model is set.Then a simulated annealing algorithm is designed for the model.Case studies show that the model decreases the total flight delay to the satisfactory solutions,and minimizes the total passengers′walking distance.The least change of planned assignment is also reached.The results achieve the goals of disruption management.Therefore,the model is verified to be effective. 展开更多
关键词 gate assignment multi-objective programming simulated annealing algorithm disruption management
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THE INFLUENCE OF COMPOSITION AND TEMPERATURE OF BATH ANDAFTER-TREATMENT 0N COLORATION IN COLORING HOT DIPGALVANIZATION 被引量:3
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作者 Q. C. Le and J. Z. Cui School of Materials & Metallurgy , Northeastern University , Shenyang 110006 , China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1217-1222,共6页
The 08 Al steel sheets were hot dip ped into Zn - Mn bath with 0 1 % Mn and 0 2 % Mn at600 ~420 ℃ bath tem perature , and then w ere treated in different w ays . The after - treat ments include cooling in t... The 08 Al steel sheets were hot dip ped into Zn - Mn bath with 0 1 % Mn and 0 2 % Mn at600 ~420 ℃ bath tem perature , and then w ere treated in different w ays . The after - treat ments include cooling in the air at room tem perature directly , holding at the upper part of thehot dip galvanizing furnace for 60 s an d then holding at 510 ±10 ℃for 90 s . The results in dicated that blue , yellow , and purple , w hose coloration varied with the co m position an d thetem perature of bath and the w ays of after - treat ment . Finally , the mechanism of coloredzinc coating w as discussed . 展开更多
关键词 coloring hot dip galvanization m anganese after - treat ment
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MEASUREMENTAL RESEARCH ON THE MAGNETOMECHANICAL COUPLING PROPERTIES OF RARERARTH GIANT MAGNETOSTRICTION MATERIALS 被引量:2
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作者 C.Y. Li1) , H.Q. Yuan2) , F.X. Meng3) and Z. Zhou4) 1) Institute of Liaoning Technology,Jinzhou 121001 ,China 2) Northeastern University ,Shenyang 10006 ,China 3) Shenyang University ,Shenyang 110044 ,China 4) Xincheng Rare Earth Magnetostrictive Mate 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第4期357-360,共4页
The physical modelanditsequivalentcircuitoftestapparatusissetup by meansofimpedanceanalysis method. The magnetostriction coefficient, magnetomechanicalcoupling coefficient,frequency and anti- frequency of TbxDy1 - xFe... The physical modelanditsequivalentcircuitoftestapparatusissetup by meansofimpedanceanalysis method. The magnetostriction coefficient, magnetomechanicalcoupling coefficient,frequency and anti- frequency of TbxDy1 - xFe2 - z(0 27 ≤x ≤0 3 ,0 ≤z ≤0 1) rod are measured. Somecoupling problems with mechanicalstress and electromagnetic field such as flux leakage in magnetic path are discussed. The comparing calculated with tested resultsshowsthe accuracyof measurementand thesimplification of model. 展开更多
关键词 magnetostriction material magnetomechanicalcoupling properties experi ment
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Endoscopic findings of gastrointestinal involvement in Chinese patients with Behcet's disease 被引量:12
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作者 Jun Zou Yan Shen +2 位作者 Da-Nian Ji Song-Bai Zheng Jian-Long Guan 《World Journal of Gastroenterology》 SCIE CAS 2014年第45期17171-17178,共8页
AIM:To report the incidence,clinical features and outcomes of gastrointestinal(GI)involvement in Behcet’s disease(BD).METHODS:A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopi... AIM:To report the incidence,clinical features and outcomes of gastrointestinal(GI)involvement in Behcet’s disease(BD).METHODS:A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopies were performed in 148 patients.Four hundred age-and sex-matched controls were enrolled for comparison.RESULTS:Fifty-two(35.1%)patients had GI lesions.After a mean follow-up of 10 mo,ileocecal ulcers had been confirmed in 20 patients,including active ulcer(s)in 18 patients,but no ileocecal ulceration was found in controls.GI symptoms were present in 14 patients with active ulcer(s),while 4 patients with smaller ulcer were asymptomatic.Endoscopic features of ileocecalulcer were:a single ulcer(50%),larger than 1 cm in diameter(72.2%),and round/oval or volcano-type in shape(83.3%).Compared with patients without GI involvement,less ocular lesions,lower levels of albumin,erythrocyte count and hemoglobin,and higher levels of C-reactive protein and erythrocyte sedimentation rate were confirmed in the intestinal BD group.Four patients had esophageal ulcers in the BD group but no case in controls.The other endoscopic findings were similar between the two groups.The prevalence of Helicobacter pylori infection was similar in both groups.Most patients received an immunomodulator and responded well.CONCLUSION:GI lesions commonly occur in Chinese BD patients.The most frequently involved area is the ileocecal region.Esophageal ulcer might be a rare but unique lesion. 展开更多
关键词 Behcet’s DISEASE GASTROINTESTINAL involve-ment Ulc
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Non invasive blood flow measurement in cerebellum detects minimal hepatic encephalopathy earlier than psychometric tests 被引量:12
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作者 Vicente Felipo Amparo Urios +9 位作者 Carla Giménez-Garzó Omar Cauli Maria-Jesús Andrés-Costa Olga González Miguel A Serra Javier Sánchez-González Roberto Aliaga Remedios Giner-Durán Vicente Belloch Carmina Montoliu 《World Journal of Gastroenterology》 SCIE CAS 2014年第33期11815-11825,共11页
AIM: To assess whether non invasive blood flow measurement by arterial spin labeling in several brain regions detects minimal hepatic encephalopathy. METHODS: Blood flow(BF) was analyzed by arterial spin labeling(ASL)... AIM: To assess whether non invasive blood flow measurement by arterial spin labeling in several brain regions detects minimal hepatic encephalopathy. METHODS: Blood flow(BF) was analyzed by arterial spin labeling(ASL) in different brain areas of 14 controls, 24 cirrhotic patients without and 16 cirrhotic patients with minimal hepatic encephalopathy(MHE). Images were collected using a 3 Tesla MR scanner(Achieva 3T-TX, Philips, Netherlands). Pulsed ASL was performed. Patients showing MHE were detected using the battery Psychometric Hepatic Encephalopathy Score(PHES) consisting of five tests. Different cognitive and motor functions were also assessed: alterations in selective attention were evaluated using the Stroop test. Patients and controls also performed visuo-motor and bimanual coordination tests. Several biochemical parameters were measured: serum pro-inflammatory interleukins(IL-6 and IL-18), 3-nitrotyrosine, cGMP and nitrates+nitrites in plasma, and blood ammonia. Bivariate correlations were evaluated.RESULTS: In patients with MHE, BF was increased in cerebellar hemisphere(P = 0.03) and vermis(P = 0.012) and reduced in occipital lobe(P = 0.017). BF in cerebellar hemisphere was also increased in patients without MHE(P = 0.02). Bimanual coordination was impaired in patients without MHE(P = 0.05) and much more in patients with MHE(P < 0.0001). Visuo-motor coordination was impaired only in patients with MHE(P < 0.0001). Attention was slightly affected in patients without MHE and more strongly in patients with MHE(P< 0.0001). BF in cerebellar hemisphere and vermis correlated with performance in most tests of PHES [(number connection tests A(NCT-A), B(NCT-B)and line tracing test] and in the congruent task of Stroop test. BF in frontal lobe correlated with NCT-A. Performance in bimanual and visuomotor coordination tests correlated only with BF in cerebellar hemisphere. BF in occipital lobe correlates with performance in the PHES battery and with CFF. BF in cerebellar hemisphere correlates with plasma cGMP and nitric oxide(NO) metabolites. BF in vermis cerebellar also correlates with NO metabolites and with 3-nitrotyrosine. IL-18 in plasma correlates with BF in thalamus and occipital lobe.CONCLUSION: Non invasive BF determination in cerebellum using ASL may detect MHE earlier than the PHES. Altered NO-cGMP pathway seems to be associated to altered BF in cerebellum. 展开更多
关键词 ARTERIAL SPIN labelling NEUROLOGICAL impair-ment B
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Outcome of surgical treatment of intestinal perforation in typhoid fever 被引量:1
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作者 Aziz Sümer zgür Kemik +6 位作者 Ahmet Cumhur Dülger Aydemir Olmez Ismail Hasirci Erol Kisli Vedat Bayrak Gulay Bulut etin Kotan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第33期4164-4168,共5页
AIM:To represent our clinical experience in the treatment of intestinal perforation arising from typhoid fever.METHODS:The records of 22 surgically-treated patients with typhoid intestinal perforation were evaluated r... AIM:To represent our clinical experience in the treatment of intestinal perforation arising from typhoid fever.METHODS:The records of 22 surgically-treated patients with typhoid intestinal perforation were evaluated retrospectively.RESULTS:There were 18 males and 4 females,mean age 37 years(range,8-64 years).Presenting symptoms were fever,abdominal pain,diarrhea or constipation.Sixteen cases were subjected to segmental resection and end-to-end anastomosis,while 3 cases received 2-layered primary repair following debridement,one case with multiple perforations received 2-layered primary repair and end ileostomy,one case received segmental resection and end-to-end anastomosis followed by an end ileostomy,and one case received segmental resection and end ileostomy with mucous fistula operation.Postoperative morbidity was seen in 5 cases and mortality was found in one case.CONCLUSION:Intestinal perforation resulting from Salmonella typhi is an important health problem in Eastern and Southeastern Turkey.In management of this illness,early and appropriate surgical intervention is vital. 展开更多
关键词 Intestinal perforation Typhoid fever Treat- ment
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Deformation and Development Tendency of Shiliushubao Landslide by Numerical Modeling 被引量:1
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作者 LI Xiuzhen KONG Jiming XU Qiang 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期840-846,共7页
On the basis of analysing basic features of Shiliushubao landslide, the landslide's deformation and development tendency are quantitatively studied by using FLA^3D program. The results accord with monitoring results.... On the basis of analysing basic features of Shiliushubao landslide, the landslide's deformation and development tendency are quantitatively studied by using FLA^3D program. The results accord with monitoring results. The results are indicated that resevoir impounding accelerates the landslide's deformation, and the variation of reservoir water level is key factor of affecting the deformation; The landslide has the characters of pull-behind move ment according to the displacement of the landslide body gradually reducing from leading edge to trailing edge; Excavating and deloading slow down the landslide's deformation in the certain degree. On the basis, the deformation developmental tendency of Shiliushubao landslide is predicted by the established simulating model. 展开更多
关键词 Shiliushubao landslide deformation rule develop ment tendency numerical modeling
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Influence of Steel and Carbon Fiber Reinforcement Bars on Seismic Performance of Precast Segmental Bridge Columns 被引量:4
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作者 布占宇 《宁波大学学报(理工版)》 CAS 2012年第4期75-82,共8页
为了得到快速施工和利用新材料的预制节段桥墩设计方法,研究了部分钢筋替换为碳纤维筋时预制节段桥墩的水平承载力和破坏等级.首先通过与拟静力试验结果的比较证明了仿真分析的正确性,然后研究了部分普通钢筋替换为碳纤维筋,对拟静... 为了得到快速施工和利用新材料的预制节段桥墩设计方法,研究了部分钢筋替换为碳纤维筋时预制节段桥墩的水平承载力和破坏等级.首先通过与拟静力试验结果的比较证明了仿真分析的正确性,然后研究了部分普通钢筋替换为碳纤维筋,对拟静力循环荷载和地震地面运动分别作用时预制节段桥墩响应的影响.结果表明:碳纤维筋能提高桥墩水平承载力,增大有效刚度,降低等效粘滞阻尼比和滞回能量耗散.地震时程计算表明:部分普通钢筋替换为碳纤维筋时,使得预制节段桥墩在较强烈地震底面运动下不倒塌.利用绝对能量法分析了桥墩在地震地面运动下的能量吸收和耗散情况,并主要研究了4种桥墩试件在3种不同地震地面运动作用下的输入能量和滞回能量耗散,结果是随着桥墩输入地震能量的增大滞回能量耗散增长缓慢. 展开更多
关键词 预制施工 预制节段桥墩 地震响应 碳纤维筋 能量耗散
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GRANITOIDS,VOLCANIC ROCKS AND CHERTS FROM NORTH ALTYN TAGH,NW CHINA: IMPLICATION FOR THE TECTONIC ENVIRONMENT DISCRIMINATION
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作者 Chen Xuanhua\+1,Wang Xiaofeng\+1,Chen Zhengle\+1,George Gehrels\+2,Yin An\+3 2.Department of Geosciences, University of Arizona,Tucson,AZ 85721,USA 3.Department of Earth and Space Science 《地学前缘》 EI CAS CSCD 2000年第S1期249-250,共2页
Granitoids,volcanic rocks and cherts,mainly of early Paleozoic,in northern Altyn Tagh(Fig.1) are analyzed here for the purpose of the determination of the tectonic environments and their development since Early Paleoz... Granitoids,volcanic rocks and cherts,mainly of early Paleozoic,in northern Altyn Tagh(Fig.1) are analyzed here for the purpose of the determination of the tectonic environments and their development since Early Paleozoic.(1) Granitoids\ The collection of 128 main\|element petrochemical data from North Altyn Tagh area shows that most of the granitoids here are granites and granodiorites of calc\|alkaline series.They consist mainly of metaluminous and peraluminous in Shand’s index,and only one of them,which belongs to Mesozoic,is peralkaline.Most of the granitoids plot in the IAG+CAG+CCG fields in the Maniar and Piccoli’s diagrams (1989) for tectonic discrimination of granitoids.IAG (Island arc granitoids)and CAG (Continental arc granitoids) can be distinguished for Early and Late Paleozoic granitoids,and maybe some CCG (Continental collision granitoids) for Early Paleozoic.Granitoids of Mesozoic and Cenozoic inherited the characteristics of those of Paleozoic.Destructive active plate margin (pre\|plate collision)and Anatectic magmatism(syn\|orogenic,S\|type granites)are distinguished (Fig.2)for Paleozoic granitoids using de la Roche R 1\| R 2 multicationic diagram (Batchelor and Bowden,1985).Mesozoic and Cenozoic granitoids inherited the characteristics of Anatectic magmatism (syn\|orogenic)of these early ones,and post\|orogenic(A\|type)granites occurred in Mesozoic.The mechanism for magma formation is mainly partial melting. 展开更多
关键词 GRANITOIDS VOLCANIC ROCKS CHERTS TECTONIC environ ment Altyn Tagh
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