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Intoxication Induced by Urea Containing Diets in Broiler Chickens: Effect on Weight Gain, Feed Conversion Ratio, Hematological and Biochemical Profiles
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作者 Mohammed Al-Zharani Mohammed Mubarak +2 位作者 Hassan Ahmed Rudayni Mahmoud M. Abdelwahab Mohammed Al-Eissa 《Advances in Bioscience and Biotechnology》 CAS 2023年第3期106-119,共14页
Urea as a source of cheap non-protein nitrogen is used to adulterate fish and meat meals which are basic components of broiler diets. The present study was carried out to elucidate the effects of urea on weight gain, ... Urea as a source of cheap non-protein nitrogen is used to adulterate fish and meat meals which are basic components of broiler diets. The present study was carried out to elucidate the effects of urea on weight gain, and hematological and biochemical profiles. A total of 48 broiler chicks were randomly allotted into 4 groups, designated Groups 1, 2, 3 and 4 of 12 birds each. Birds in Groups 2, 3 and 4 were fed on diets containing urea at the levels of 1%, 2.5% and 4%, respectively. Birds in Group 1 served as control and were not exposed to urea. Experimentation period was for 3 weeks and experiment was terminated when birds were 42 days of age. Body weight of all intoxicated birds at the various intervals was significantly decreased in comparison with that of the untreated control. Compared with control, all intoxicated broilers manifested significant (P ≤ 0.05) decrease in all hematological parameters involving erythrocytic and total leucocytic counts, Hemoglobin (Hb) and Packed Cell Volume (PCV) on a dose- and time-pattern. In comparison with the control levels, biochemical profile of the intoxicated birds disclosed significant decrease in blood glucose level and significant increase in serum uric acid, urea, Alkaline Phosphatase (ALP) and Lactate Dehydrogenase (LDH) levels. Based upon the present data, it was concluded that the addition of urea to broiler diets bears serious sequences concerning the general health condition, performance, weight gain, and hematological and biochemical profiles. 展开更多
关键词 UREA INtoXICATION Broiler Chickens weight Gain Feed Conversion ratio
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Therapeutic effect of nerve growth factor on cerebral infarction in dogs using the hemisphere anomalous volume ratio of diffusion-weighted magnetic resonance imaging 被引量:9
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作者 Yong Wang Hui Zhang +5 位作者 Zhe Wang Zuojun Geng Huaijun Liu Haiqing Yang Peng Song Qing Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1873-1880,共8页
A model of focal cerebral ischemic infarction was established in dogs through middle cerebral artery occlusion of the right side.Thirty minutes after occlusion,models were injected with nerve growth factor adjacent to... A model of focal cerebral ischemic infarction was established in dogs through middle cerebral artery occlusion of the right side.Thirty minutes after occlusion,models were injected with nerve growth factor adjacent to the infarct locus.The therapeutic effect of nerve growth factor against cerebral infarction was assessed using the hemisphere anomalous volume ratio,a quantitative index of diffusion-weighted MRI.At 6 hours,24 hours,7 days and 3 months after modeling,the hemisphere anomalous volume ratio was significantly reduced after treatment with nerve growth factor. Hematoxylin-eosin staining,immunohistochemistry,electron microscopy and neurological function scores showed that infarct defects were slightly reduced and neurological function significantly improved after nerve growth factor treatment.This result was consistent with diffusion-weighted MRI measurements.Experimental findings indicate that nerve growth factor can protect against cerebral infarction,and that the hemisphere anomalous volume ratio of diffusion-weighted MRI can be used to evaluate the therapeutic effect. 展开更多
关键词 diffusion-weighted MRI nerve growth factor hemisphere anomalous volume ratio cerebral infarction treatment NEUROPROTECTION brain regeneration neural regeneration
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A Modified Bi-Directional Evolutionary Structural Optimization Procedure with Variable Evolutionary Volume Ratio Applied to Multi-Objective Topology Optimization Problem
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作者 Xudong Jiang Jiaqi Ma Xiaoyan Teng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期511-526,共16页
Natural frequency and dynamic stiffness under transient loading are two key performances for structural design related to automotive,aviation and construction industries.This article aims to tackle the multi-objective... Natural frequency and dynamic stiffness under transient loading are two key performances for structural design related to automotive,aviation and construction industries.This article aims to tackle the multi-objective topological optimization problem considering dynamic stiffness and natural frequency using modified version of bi-directional evolutionary structural optimization(BESO).The conventional BESO is provided with constant evolutionary volume ratio(EVR),whereas low EVR greatly retards the optimization process and high EVR improperly removes the efficient elements.To address the issue,the modified BESO with variable EVR is introduced.To compromise the natural frequency and the dynamic stiffness,a weighting scheme of sensitivity numbers is employed to form the Pareto solution space.Several numerical examples demonstrate that the optimal solutions obtained from the modified BESO method have good agreement with those from the classic BESO method.Most importantly,the dynamic removal strategy with the variable EVR sharply springs up the optimization process.Therefore,it is concluded that the modified BESO method with variable EVR can solve structural design problems using multi-objective optimization. 展开更多
关键词 Bi-directional evolutionary structural optimization variable evolutionary volume ratio multi-objective optimization weighted sum topology optimization
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Effects of Temperature and Catalyst to Oil Weight Ratio on the Catalytic Conversion of Heavy Oil to Propylene Using ZSM-5 and USY Catalysts 被引量:10
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作者 Xiaohong Li Chunyi Li Jianfang Zhang Chaohe Yang Honghong Shan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期92-99,共8页
It is useful for practical operation to study the rules of production of propylene by the catalytic conversion of heavy oil in FCC (fluid catalytic cracking). The effects of temperature and C/O ratio (catalyst to o... It is useful for practical operation to study the rules of production of propylene by the catalytic conversion of heavy oil in FCC (fluid catalytic cracking). The effects of temperature and C/O ratio (catalyst to oil weight ratio) on the distribution of the product and the yield of propylene were investigated on a micro reactor unit with two model catalysts, namely ZSM-5/Al2O3 and USY/Al2O3, and Fushun vacuum gas oil (VGO) was used as the feedstock. The conversion of heavy oil over ZSM-5 catalyst can be comparable to that of USY catalyst at high temperature and high C/O ratio. The rate of conversion of heavy oil using the ZSM-5 equilibrium catalyst is lower compared with the USY equilibrium catalyst under the general FCC conditions and this can be attributed to the poor steam ability of the ZSM-5 equilibrium catalyst. The difference in pore topologies of USY and ZSM-5 is the reason why the principal products for the above two catalysts is different, namely gasoline and liquid petroleum gas (LPG), repspectively. So the LPG selectivity, especially the propylene selectivity, may decline if USY is added into the FCC catalyst for maximizing the production of propylene. Increasing the C/O ratio is the most economical method for the increase of LPG yield than the increase of the temperature of the two model catalysts, because the loss of light oil is less in the former case. There is an inverse correlation between HTC (hydrogen transfer coefficient) and the yield of propylene, and restricting the hydrogen transfer reaction is the more important measure in increasing the yield of propylene of the ZSM-5 catalyst. The ethylene yield of ZSM-5/A1203 is higher, but the gaseous side products with low value are not enhanced when ZSM-5 catalyst is used. Moreover, for LPG and the end products, dry gas and coke, their ranges of reaction conditions to which their yields are dependent are different, and that of end products is more severe than that of LPG. So it is clear that maximizing LPG and propylene and restricting dry gas and coke can be both achieved via increasing the severity of reaction conditions among the range of reaction conditions which LPG yield is sensitive to. 展开更多
关键词 fluid catalytic cracking heavy oil PROPYLENE temperature catalyst to oil weight ratio ZSM-5 USY
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Feasibility study on buoyancy-weight ratios of a submerged floating tunnel prototype subjected to hydrodynamic loads 被引量:7
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作者 Xu Long Fei Ge Youshi Hong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第5期750-761,共12页
The research progress of a novel traffic solution,a submerged floating tunnel(SFT),is reviewed in terms of a study approach and loading scenario.Among existing publications,the buoyancy-weight ratio(BWR) is usuall... The research progress of a novel traffic solution,a submerged floating tunnel(SFT),is reviewed in terms of a study approach and loading scenario.Among existing publications,the buoyancy-weight ratio(BWR) is usually predefined.However,BWR is a critical structural parameter that tremendously affects the dynamic behaviour of not only the tunnel tube itself but also the cable system.In the context of a SFT prototype(SFTP) project in Qiandao Lake(Zhejiang Province,China),the importance of BWR is illustrated by finite element analysis and subsequently,an optimized BWR is proposed within a reasonable range in the present study.In the numerical model,structural damping is identified to be of importance.Rayleigh damping and the corresponding Rayleigh coefficients are attained through a sensitivity study,which shows that the adopted damping ratios are fairly suitable for SFTP.Lastly,the human sense of security is considered by quantifying the comfort index,which helps further optimize BWR in the SFTP structural parameter design. 展开更多
关键词 Submerged floating tunnel Buoyancy-weight ratio Water wave and current loads Dynamic response Human security sense Comfort index
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Successful living donor liver transplantation with a graft-to-recipient weight ratio of 0.41 without portal flow modulation:A case report
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作者 Seong Hoon Kim 《World Journal of Clinical Cases》 SCIE 2022年第16期5414-5419,共6页
BACKGROUND There have been numerous efforts to lower the limit of minimum graft size to meet the metabolic demand of recipients in adult-to-adult living donor liver transplantation(LDLT).We experienced a successful ca... BACKGROUND There have been numerous efforts to lower the limit of minimum graft size to meet the metabolic demand of recipients in adult-to-adult living donor liver transplantation(LDLT).We experienced a successful case of LDLT using a verysmall-for-size graft without portal flow modulation such as splenectomy or portocaval shunt.CASE SUMMARY A 49-year-old man(weighing 91 kg)suffering hepatocellular carcinoma accompanied with hepatitis B virus related cirrhosis underwent LDLT.The one and only voluntary donor was his 17-year-old daughter whose body weight was 50 kg with a body mass index(BMI)of 18.3.The procured right liver graft was 411 g with a real graft-to-recipient weight ratio(GRWR)of 0.41%,the smallest to be reported in the literature.Both the recipient and donor had an uneventful recovery and were discharged on days 15 and 8,respectively,with normal liver function.The father and daughter have had no complication so far and are still in good health with normal liver function 81 mo after LDLT.CONCLUSION Satisfactory outcomes can be achieved in LDLT with a GRWR as low as 0.41%even without using portal flow modulation in highly selected patients. 展开更多
关键词 Small-for-size graft Living donor liver transplantation Graft-to-recipient weight ratio Case report
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Effects of Fiber Weight Ratio, Structure and Fiber Modification onto Flexural Properties of Luffa-Polyester Composites
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作者 Lassaad Ghali Slah Msahli +1 位作者 Mondher Zidi Faouzi Sakli 《Advances in Materials Physics and Chemistry》 2011年第3期78-85,共8页
The effect of chemical modification, reinforcement structure and fiber weight ratio on the flexural proprieties of Luffa-polyester composites was studied. A unsaturated polyester matrix reinforced with a mat of Luffa ... The effect of chemical modification, reinforcement structure and fiber weight ratio on the flexural proprieties of Luffa-polyester composites was studied. A unsaturated polyester matrix reinforced with a mat of Luffa external wall fibers (ComLEMat), a short Luffa external wall fibers(ComLEBC) and a short Luffa core fi-bers (ComLCBC) was fabricated under various conditions of fibers treatments (combined process, acetylat-ing and cyanoethylating) and fiber weight ratio. It resorts that acetylating and cyanoethylating enhance the flexural strength and the flexural modulus. The fiber weight ratio influenced the flexural properties of com-posites. Indeed, a maximum value of strength and strain is observed over a 10% fiber weight ratio. The uses of various reinforcement structures were investigated. The enhancement of elongation at break and the strain values of the composite reinforced by natural mat was proved. 展开更多
关键词 LUFFA Fibers COMPOSITE FLEXURAL Properties FIBER weight ratio
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The spike weight contribution of the photosynthetic area above the upper internode in a winter wheat under different nitrogen and mulching regimes 被引量:5
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作者 Wei Chen Jingjuan Zhang Xiping Deng 《The Crop Journal》 SCIE CAS CSCD 2019年第1期89-100,共12页
Besides leaves, non-foliar green organs such as stem and spike are also considered photosynthetic organs. To assess the photosynthetic contributions of these organs, the correlations between these photosynthetic areas... Besides leaves, non-foliar green organs such as stem and spike are also considered photosynthetic organs. To assess the photosynthetic contributions of these organs, the correlations between these photosynthetic areas and single-spike weight were investigated in a winter wheat(Triticum aestivum L.) under four nitrogen and mulching treatments: N120,N150, N195, and N195 + M. Two-year repeated field experiments were conducted on the Loess Plateau of China. Non-foliar photosynthetic area, grain-filling ratio and duration,grain yield, and in particular, single-spike weight, were measured, recorded and analyzed.Under the N195 + M treatment, plants showed the largest area of photosynthetic organs(flag leaf and non-foliar organs) and the highest grain yield and single spike weight. Singlespike weight was positively correlated with the areas of all examined non-foliar photosynthetic organs, in particular with the area above the flag leaf node(R^2= 0.761*)and the area above the exposed part of the peduncle(EXP)(R^2= 0.800**). In addition, singlespike weight was highly correlated with average grain-filling ratio(R^2= 0.993**), whereas it was less highly correlated with grain-filling duration(R^2= 0.533). The morphological traits of non-foliar photosynthetic organs were also more highly correlated with average grainfilling ratio than with average grain-filling duration. The significant correlation between each of the morphological traits(area, length and width) of EXP and single-spike weight indicates that morphological traits of EXP are important in determining spike weight in the Loess Plateau environment. 展开更多
关键词 GRAIN-FILLING ratio GRAIN-FILLING duration LOESS Plateau PHOtoSYNTHETIC organs Single SPIKE weight Winter wheat
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Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions 被引量:8
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作者 Seung Duk Lee Seong Hoon Kim +2 位作者 Young-Kyu Kim Soon-Ae Lee Sang-Jae Park 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第1期18-24,共7页
BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate wh... BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. METHODS: From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7%(group A), 27 had a GRWR of ≥0.7%, 【0.8%(group B), and 267 had a GRWR of more than and equal to 0.8%(group C). Medical records, including recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. RESULTS: The baseline demographics showed low model for end-stage liver disease score(mean 16.3±8.9) and high percentage of hepatocellular carcinoma(231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For smallforsize syndrome, there were 3(13.0%) in group A, 1(3.7%) in group B, and 2 patients(0.7%) in group C(P【0.001). Hepatic artery thrombosis was more frequently observed in group A than in groups B and C(8.7% vs 3.7% vs 1.9%, P=0.047). However, among the three groups, graft survival rates at 1 year(100% vs 96.3% vs 93.6%) and 3 years(91.7% vs 73.2% vs 88.1%) were not different(P=0.539). In laboratory measurements,there was no group difference in total bilirubin and albumin. However, prothrombin time was longer in group A within postoperative 1 week and platelet count was lower in groups A and B within postoperative 1 month. CONCLUSION: A GRWR lower to 0.7% is safe and does not need to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score. 展开更多
关键词 graft-to-recipient weight ratio living donor liver transplantation small-for-size graft small-for-size syndrome
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Experimental Investigation of Multi-Mode Vortex-Induced Vibration of Flexible Risers with Different Mass Ratios
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作者 WANG Yu LOU Min +3 位作者 REN Xiao-hui LIANG Wei-xing LI Xiang DANG Peng-bo 《China Ocean Engineering》 SCIE EI CSCD 2023年第1期1-15,共15页
Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 16... Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 1600-14400. The dynamic responses of riser models versus reduced velocity were analyzed, and the spanwise displacement, frequency,and trajectory of the mode conversion from the lower to the higher mode were explored. The results revealed that the riser model with a higher mass ratio excites a higher number of modes. The conversion region of multi-mode competition exists and narrows with the increasing mass ratio. Mode conversion is continuous and manifests as the transmission of peaks and troughs in mode shape: the peaks and troughs of mode shape move up in the mode stable development region and move down in the mode conversion region. The single-mode dominating vibration exhibits a standing wave feature, and the traveling wave feature is significant in the mode conversion region. Furthermore, the frequency jump is always transmitted from the trough to the peak of the mode shape, and finally, all the axial positions vibrate at the same frequency. The trajectory in the mode conversion region deviates from the 8-shape and recovers the standard8-shape at the middle and late stages of the mode stable development region. 展开更多
关键词 vortex-induced vibration dynamic response mode conversion mass ratio mode weight
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Critical weight on bit of double-driven bottomhole assembly during vertical and fast drilling 被引量:1
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作者 祝效华 贾彦杰 童华 《Journal of Central South University》 SCIE EI CAS 2012年第2期572-577,共6页
It is difficult to determine the optimal weight on bit (WOB) of the double-driven bottomhole assembly (DD-BHA, with double stabilizers and a bent housing positive displacement motor (PDM)) which is employed during ver... It is difficult to determine the optimal weight on bit (WOB) of the double-driven bottomhole assembly (DD-BHA, with double stabilizers and a bent housing positive displacement motor (PDM)) which is employed during vertical and fast drilling. High WOB leads to well deviation out of control, and low WOB leads to low rate of penetration (ROP). So considering the rock physical properties, the anisotropy index function of polycrystalline diamond compact (PDC) bit was derived with the structure and cutting performance parameters of the bit, and the effect of natural hole deviation tendencies on the performance of DD-BHA resisting deviation was represented. The concept of elliptic deformation ratio was used to characterize the performance of DD-BHA resisting deviation. Eventually, a model calculating the critical WOB was established. By comparing the model predictions with the measured hole angle changes in the field, the results show that the model predictions are accurate with error less than 5.8%, which can meet the operational requirements in the projects. Furthermore, the model was adopted to justify and guide the operating conditions and parameters during drilling, which shows that the optimum WOB predicted by the model can not only control deviation but also improve ROP effectively. The model is independent on the formation characteristics of blocks, so it can be expanded widely to other oilfields. 展开更多
关键词 double-driven bottomhole assembly vertical and fast drilling critical weight of bit elliptic deformation ratio bit anisotropy
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基于熵权TOPSIS法与秩和比法的高校附属医院科技成果转化评价研究
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作者 赵佳洁 郝三元 +2 位作者 许紫文 许栋 陈任 《中国医院管理》 北大核心 2024年第11期18-24,共7页
目的评价安徽省某医科大学12家附属医院科技成果转化工作,为进一步优化高校附属医院科技成果转化提供建议。方法根据所收集的数据使用熵权法为评价指标体系赋权,采用TOPSIS法与秩和比法模糊联合进行综合评价。结果评价指标中权重排名前... 目的评价安徽省某医科大学12家附属医院科技成果转化工作,为进一步优化高校附属医院科技成果转化提供建议。方法根据所收集的数据使用熵权法为评价指标体系赋权,采用TOPSIS法与秩和比法模糊联合进行综合评价。结果评价指标中权重排名前3位的是以自行实施方式转化的到账总金额(4.801%),以与他人合作实施方式转化获得收益的到账总金额(4.801%),与所属高校共建研发机构、转移机构、转化服务平台数量(4.779%)。模糊联合结果中前3名医院分别为A、C、G,后3名分别为K、H、E。医院之间差异明显,直属附属医院与非直属附属医院存在差异。结论高校附属医院应探索一条具有自身特色的科技成果转化的发展道路,从实际出发作转化;将成果转化融入学科建设,深化拓展科研优势;构建转化意识提升体系,以意识提升带动行动;高校牵头医工融合,搭建医产学研新生态。 展开更多
关键词 科技成果转化 高校附属医院 熵权toPSIS法 秩和比法
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Carbon isotopic fractionation during vaporization of low molecular weight hydrocarbons(C6–C12)
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作者 Qian-Yong Liang Yong-Qiang Xiong +2 位作者 Jing Zhao Chen-Chen Fang Yun Li 《Petroleum Science》 SCIE CAS CSCD 2017年第2期302-314,共13页
Three series of laboratory vaporization experiments were conducted to investigate the carbon isotope fractionation of low molecular weight hydrocarbons(LMWHs)during their progressive vaporization.In addition to the ... Three series of laboratory vaporization experiments were conducted to investigate the carbon isotope fractionation of low molecular weight hydrocarbons(LMWHs)during their progressive vaporization.In addition to the analysis of a synthetic oil mixture,individual compounds were also studied either as pure single phases or mixed with soil.This allowed influences of mixing effects and diffusion though soil on the fractionation to be elucidated.The LMWHs volatilized in two broad behavior patterns that depended on their molecular weight and boiling point.Vaporization significantly enriched the ^13C present in the remaining components of the C6–C9 fraction,indicating that the vaporization is mainly kinetically controlled;the observed variations could be described with a Rayleigh fractionation model.In contrast,the heavier compounds(n-C10–n-C12)showed less mass loss and almost no significant isotopic fractionation during vaporization,indicating that the isotope characteristics remained sufficiently constant for these hydrocarbons to be used to identify the source of an oil sample,e.g.,the specific oil field or the origin of a spill.Furthermore,comparative studies suggested that matrix effects should be considered when the carbon isotope ratios of hydrocarbons are applied in the field. 展开更多
关键词 Low molecular weight hydrocarbons Gas chromatography-isotope ratio mass spectrometry Isotope fractionation VAPORIZATION
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Research on a Rapid Test Method of Dry Basis Weight of Paper-process Reconstituted Tobacco
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作者 Dandan SU Hua CHEN +4 位作者 Guangfei ZHAO Liran DING Wenjun ZHANG Jing LIU Guiyuan ZHOU 《Agricultural Science & Technology》 CAS 2017年第10期1948-1950,1978,共4页
This study aimed to optimize the rapid test factors of dry basis weight of reconstituted tobacco, in order to afford a reference test method for companies which produce reconstituted tobacco to better control the basi... This study aimed to optimize the rapid test factors of dry basis weight of reconstituted tobacco, in order to afford a reference test method for companies which produce reconstituted tobacco to better control the basis weight and coating ratio on line. The dry basis weight of reconstituted tobacco was tested by fast method and normal oven method individually. And the effects on the test values of different test factors such as temperature, time and the number of baking sheets were studied. Then the test values of these two methods were compared, so the proper factors of rapid test method were determined. As the baking temperature rose from 130 ℃ to 150 ℃, and the baking time rose from 1 min to 2 min, the difference between fast test method and normal oven method grew, and when the number of baking pieces rose from 3 pieces to 5 pieces, the difference between the two methods went down. The optimum test condition was baking temperature of 130 ℃, baking time of 1 min, and baking sample sheet number of 5. Under this condition, the value of fast test method was the closest to the test value of normal oven method, and meanwhile, the test factor was more proper for testing on line. The study will provide a reference for online controlling of dry basis weight and coating ratio of reconstituted tobacco. 展开更多
关键词 Reconstituted tobacco Rapid test method Dry basis weight Coating ratio
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Minimum MSE Weighted Estimator to Make Inferences for a Common Risk Ratio across Sparse Meta-Analysis Data
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作者 Chukiat Viwatwongkasem Sutthisak Srisawad +4 位作者 Pichitpong Soontornpipit Jutatip Sillabutra Pratana Satitvipawee Prasong Kitidamrongsuk Hathaikan Chootrakool 《Open Journal of Statistics》 2022年第1期49-69,共21页
The paper aims to discuss three interesting issues of statistical inferences for a common risk ratio (RR) in sparse meta-analysis data. Firstly, the conventional log-risk ratio estimator encounters a number of problem... The paper aims to discuss three interesting issues of statistical inferences for a common risk ratio (RR) in sparse meta-analysis data. Firstly, the conventional log-risk ratio estimator encounters a number of problems when the number of events in the experimental or control group is zero in sparse data of a 2 × 2 table. The adjusted log-risk ratio estimator with the continuity correction points  based upon the minimum Bayes risk with respect to the uniform prior density over (0, 1) and the Euclidean loss function is proposed. Secondly, the interest is to find the optimal weights of the pooled estimate  that minimize the mean square error (MSE) of  subject to the constraint on  where , , . Finally, the performance of this minimum MSE weighted estimator adjusted with various values of points  is investigated to compare with other popular estimators, such as the Mantel-Haenszel (MH) estimator and the weighted least squares (WLS) estimator (also equivalently known as the inverse-variance weighted estimator) in senses of point estimation and hypothesis testing via simulation studies. The results of estimation illustrate that regardless of the true values of RR, the MH estimator achieves the best performance with the smallest MSE when the study size is rather large  and the sample sizes within each study are small. The MSE of WLS estimator and the proposed-weight estimator adjusted by , or , or are close together and they are the best when the sample sizes are moderate to large (and) while the study size is rather small. 展开更多
关键词 Minimum MSE weights Adjusted Log-Risk ratio Estimator Sparse Meta-Analysis Data Continuity Correction
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Effect of Fiber Weight Ratio and Fiber Modification on Flexural Properties of Posidonia-Polyester Composites
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作者 S. Zannen L. Ghali +1 位作者 M. T. Halimi M. Ben Hassen 《Open Journal of Composite Materials》 2016年第3期69-77,共9页
The main objective of this research is to study the effect of fiber weight ratio and chemical fiber modification on flexural properties of composites reinforced with Posidonia fiber. An unsaturated polyester matrix re... The main objective of this research is to study the effect of fiber weight ratio and chemical fiber modification on flexural properties of composites reinforced with Posidonia fiber. An unsaturated polyester matrix reinforced with untreated and treated Posidonia fibers was fabricated under various fiber weight ratios. Results showed that the combined chemical treatment provided better mechanical properties of composites in comparison with untreated fiber. The fiber weight ratio influenced the flexural properties of composites. Indeed, a maximum value of flexural modulus was observed for 10% fiber weight ratio for composites reinforced with treated fibers. SEM photographs revealed a different fracture surface between Posidonia fibers reinforced polyester composites. 展开更多
关键词 Composites Posidonia Fiber weight ratio Flexural Modulus Flexural Strength ELONGATION SEM Micrographs
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基于熵权-TOPSIS-秩和比法的国企医院运营评价研究
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作者 赵新哲 曲朝晖 杨长青 《中国医院》 北大核心 2024年第7期71-75,共5页
目的:探索建立与公立医院高质量发展相协调、与国企医院发展实际相适配、满足集团化管理需求的国企医院运营评价体系,为国企医院加强运营管理提供参考。方法:以某国有企业重点管理的27所国企医院为样本,通过熵权法确定运营指标体系权重... 目的:探索建立与公立医院高质量发展相协调、与国企医院发展实际相适配、满足集团化管理需求的国企医院运营评价体系,为国企医院加强运营管理提供参考。方法:以某国有企业重点管理的27所国企医院为样本,通过熵权法确定运营指标体系权重,应用TOPSIS法对2021-2023年样本医院运营评价进行排序,使用秩和比法对样本医院进行分档。结果:一级指标权重由高到低分别为运行效率(23.00%)、资源产出(20.75%)、业务规模(19.01%)、诊疗结构(18.89%)和质量控制(18.35%);二级指标权重差异较大,由2.358%到4.828%不等;大部分样本医院在3年间的运营水平稳步提升;27所样本医院可分为4类,分别为示范医院4所、潜力医院10所、普通医院9所和待提升医院4所,类别差异具有统计学意义(F=71.822,P<0.001)。结论:熵权-TOPSIS-秩和比综合评价法与国企医院运营评价需求相适配;国企医院运营评价得以整体提升,主要源于运营管控型集团化管理的成功实践;国企医院运营提升情况存在分化趋势,需适时开展分级管理和分类赋能。 展开更多
关键词 国企医院 运营评价 熵权法 toPSIS 秩和比法
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基于加权Topsis-秩和比法评价肿瘤科药品不良反应报告质量 被引量:3
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作者 吴娜 苏丹 +1 位作者 王海坤 沈爱宗 《中国药物警戒》 2023年第1期101-105,共5页
目的建立药品不良反应(ADR)报告质量综合评价体系,为科学评价肿瘤科ADR报告质量提供参考。方法参照相关评分标准及文件,制定ADR报告质量评价标准。使用加权逼近理想解排序(Topsis)与秩和比(RSR)相结合的方法,对2021年某院药学部收到的12... 目的建立药品不良反应(ADR)报告质量综合评价体系,为科学评价肿瘤科ADR报告质量提供参考。方法参照相关评分标准及文件,制定ADR报告质量评价标准。使用加权逼近理想解排序(Topsis)与秩和比(RSR)相结合的方法,对2021年某院药学部收到的120例肿瘤科ADR原始报告质量进行评价并分档。结果20例报告质量中等(C_(i)>0.5700);75例报告质量合格(0.3600<C_(i)≤0.5700);25例报告质量不合格(C_(i)≤0.3600)。报告主要存在问题包括ADR过程描述过于简短,药品信息错误、不全等。结论基于加权Topsis-RSR法评价ADR报告质量,可避免单一方法的局限性,具有操作切实可行,结果具体科学的优点。评价结果表明某院肿瘤科ADR报告质量仍有待提升。 展开更多
关键词 药品不良反应 报告质量 加权toPSIS法 秩和比法 肿瘤
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Splenectomy in living donor liver transplantation and risk factors of portal vein thrombosis 被引量:4
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作者 Nobuhiko Kurata Yasuhiro Ogura +3 位作者 Satoshi Ogiso Yasuharu Onishi Hideya Kamei Yasuhiro Kodera 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第4期337-342,共6页
Background:Graft inflow modulation(GIM)during adult-to-adult living donor liver transplantation(LDLT)is a common strategy to avoid small-for-size syndrome,and some transplant surgeons attempt small size graft strategy... Background:Graft inflow modulation(GIM)during adult-to-adult living donor liver transplantation(LDLT)is a common strategy to avoid small-for-size syndrome,and some transplant surgeons attempt small size graft strategy with frequent GIM procedures,which are mostly performed by splenectomy,in LDLT.However,splenectomy can cause serious complications such as portal vein thrombosis and overwhelming postsplenectomy infection.Methods:Forty-eight adult-to-adult LDLT recipients were enrolled in this study and retrospectively reviewed.We applied the graft selection criteria,which routinely fulfill graft-to-recipient weight ratio≥0.8%,and consider GIM as a backup strategy for high portal venous pressure(PVP).Results:In our current strategy of LDLT,splenectomy was performed mostly due to hepatitis C and splenic arterial aneurysms,but splenectomy for GIM was intended to only one patient(2.1%).The final PVP values≤20 mmHg were achieved in all recipients,and no significant difference was observed in patient survival or postoperative clinical course based on whether splenectomy was performed or not.However,6 of 18 patients with splenectomy(33.3%)developed postsplenectomy portal vein thrombosis(PVT),while none of the 30 patients without splenectomy developed PVT after LDLT.Splenectomy was identified as a risk factor of PVT in this study(P<0.001).Our study revealed that a lower final PVP could be risk factor of postsplenectomy PVT.Conclusions:Using sufficient size grafts was one of the direct solutions to control PVP,and allowed GIM to be reserved as a backup procedure.Splenectomy should be avoided as much as possible during LDLT because splenectomy was found to be a definite risk factor of PVT.In splenectomy cases with a lower final PVP,a close follow-up is required for early detection and treatment of PVT. 展开更多
关键词 Living donor liver transplantation SPLENECtoMY PORTAL VENOUS pressure Graft-to-recipient weight ratio PORTAL VEIN THROMBOSIS
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RANGE AMBIGUITY DISTRIBUTION CHARACTERISTIC OF SPACEBORNE SAR AND ITS DESIGN CONSIDERATION 被引量:1
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作者 荆麟角 《Journal of Electronics(China)》 1995年第2期160-167,共8页
A new approach is proposed which can satisfy the range ambiguity requirement while keep the antenna width not to be enlarged and get the high quality image also. Here the chirp slope of the transmitted linear frequenc... A new approach is proposed which can satisfy the range ambiguity requirement while keep the antenna width not to be enlarged and get the high quality image also. Here the chirp slope of the transmitted linear frequency modulated pulses is reversed alternately. Therefore, during the range compression significant portion of the ambiguous return which is due to the mismatching with the signal reference function is suppressed. The suggested method provides significant improvement in range ambiguity ratio and can be utilized in attaining wider swath. 展开更多
关键词 SAR Range AMBIGUITY ratio(RAR) INCIDENCE angle PRF Uniform distribution COSINE weighting CHIRP
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