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Efficacy of fexuprazan compared with rebamipide in Korean patients with gastritis:A matching-adjusted indirect comparison
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作者 Gwang Ha Kim Hang Lak Lee 《World Journal of Clinical Cases》 SCIE 2024年第19期3890-3897,共8页
BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosi... BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosive esophagitis.Meanwhile,rebamipide is the most commonly used mucoprotective agent for acute and chronic gastritis in real-world settings in South Korea.However,there have been no studies comparing the efficacy of these two drugs yet.AIM To compare the efficacy of fexuprazan with that of rebamipide for acute and chronic gastritis.METHODS This was a matching-adjusted indirect comparison.Individual patient data from a phase III study of fexuprazan(10 mg BID)were compared with cumulative data from two matching studies of rebamipide(100 mg TID).Erosion improvement and healing rates were compared between two weeks of fexurapan,two weeks of rebamipide,and four weeks of rebamipide.The two main outcome variables were presented as percentages,and the risk differences(RD)and 95%confidence intervals(CI)were calculated for the relative treatment effects.RESULTS In the primary analysis,the erosion improvement and healing rates after a twoweek treatment with fexuprazan were 64.5%and 53.2%,respectively,while a twoweek treatment with rebamipide resulted in erosion improvement and healing rates of 43.6%(RD:21.0%;95%CI:9.6-32.3;P<0.01)and 35.6%(RD:17.6%;95%CI:6.1-29.2;P=0.003),respectively.In the additional analysis,the erosion improvement and healing rates for the two-week fexuprazan treatment(64.2%and 51.2%,respectively)were similar to those obtained during a four-week treatment with rebamipide(60.6%;RD:3.6%;95%CI:-9.8,17.0;P=0.600 and 53.5%;RD:-2.3%;95%CI:-16.1,11.5;P=0.744,respectively).CONCLUSION The two-week fexuprazan treatment was superior to the two-week rebamipide treatment and similar to the fourweek rebamipide treatment for patients with gastritis. 展开更多
关键词 GASTRITIS Erosive gastritis Fexuprazan REBAMIPIDE Matching-adjusted indirect comparison Indirect treatment comparison
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Deciphering TADF Mechanisms in Metal-Free Organic Emitters BrA-HBI:Utilizing Optimally Tuned Range-Separated Functionals for Insight
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作者 Chunyue Yu Hang Yin +2 位作者 Jie Guo Wentian Zhang Ying Shi 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第9期28-37,共10页
Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently... Metal-free organic emitters,characterized by their thermally activated delayed fluorescence(TADF)properties,offer considerable promise for the creation of highly efficient organic light-emitting diodes(OLEDs).Recently,Shao et al.presented a novel excited state intramolecular proton transfer(ESIPT)system BrA-HBI,demonstrating an emission quantum yield of up to 50%[Adv.Funct.Mater.32,2201256(2022)].However,many open issues cannot be answered solely by experimental means only and require detailed theoretical investigations.For instance,what causes the activation of TADF from the Keto^(*) tautomer and leads to fluorescence quenching in the Enol^(*)form?Herein,we provide a theoretical investigation on the TADF mechanism of the BrA-HBI molecule by optimally tuned range-separated functionals.Our findings reveal that ESIPT occurs in the BrA-HBI molecule.Moreover,we have disclosed the reason for the fluorescence quenching of the Enol^(*)form and determined that the T_(2)state plays a dominant role in the TADF phenomenon.In addition,double hybrid density functionals method was utilized to verify the reliability of optimally tuned range separation functionals on the calculation of the TADF mechanism in BrA-HBI.These findings not only provide a theoretical reference for development of highly efficient organic light-emitting diodes,but also demonstrate the effectiveness of the optimally tuned range-separated functionals in predicting the luminescence properties of TADF molecules. 展开更多
关键词 optimal finding separateD
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Multi-party semi-quantum private comparison protocol of size relation based on two-dimensional Bell states
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作者 Bing Wang Li-Hua Gong San-Qiu Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期184-192,共9页
Currently,all quantum private comparison protocols based on two-dimensional quantum states can only compare equality,via using high-dimensional quantum states that it is possible to compare the size relation in existi... Currently,all quantum private comparison protocols based on two-dimensional quantum states can only compare equality,via using high-dimensional quantum states that it is possible to compare the size relation in existing work.In addition,it is difficult to manipulate high-dimensional quantum states under the existing conditions of quantum information processing,leading to low practicality and engineering feasibility of protocols for comparing size relation.Considering this situation,we propose an innovative protocol.The proposed protocol can make size comparison by exploiting more manageable two-dimensional Bell states,which significantly enhances its feasibility with current quantum technologies.Simultaneously,the proposed protocol enables multiple participants to compare their privacies with the semi-quantum model.The communication process of the protocol is simulated on the IBM Quantum Experience platform to verify its effectiveness.Security analysis shows that the proposed protocol can withstand common attacks while preserving the privacies of all participants.Thus,the devised protocol may provide an important reference for implementation of quantum private size comparison protocols. 展开更多
关键词 two-dimensional Bell state size relation multi-party semi-quantum private comparison
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Accuracy comparison and improvement for state of health estimation of lithium-ion battery based on random partial recharges and feature engineering
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作者 Xingjun Li Dan Yu +1 位作者 Søren Byg Vilsen Daniel Ioan Stroe 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期591-604,共14页
State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging pro... State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging profiles,which overlooked the fact that the charging and discharging profiles are random and not complete in real application.This work investigates the influence of feature engineering on the accuracy of different machine learning(ML)-based SOH estimations acting on different recharging sub-profiles where a realistic battery mission profile is considered.Fifteen features were extracted from the battery partial recharging profiles,considering different factors such as starting voltage values,charge amount,and charging sliding windows.Then,features were selected based on a feature selection pipeline consisting of filtering and supervised ML-based subset selection.Multiple linear regression(MLR),Gaussian process regression(GPR),and support vector regression(SVR)were applied to estimate SOH,and root mean square error(RMSE)was used to evaluate and compare the estimation performance.The results showed that the feature selection pipeline can improve SOH estimation accuracy by 55.05%,2.57%,and 2.82%for MLR,GPR and SVR respectively.It was demonstrated that the estimation based on partial charging profiles with lower starting voltage,large charge,and large sliding window size is more likely to achieve higher accuracy.This work hopes to give some insights into the supervised ML-based feature engineering acting on random partial recharges on SOH estimation performance and tries to fill the gap of effective SOH estimation between theoretical study and real dynamic application. 展开更多
关键词 Feature engineering Dynamic forklift aging profile State of health comparison Machine learning Lithium-ion batteries
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Efficacy comparison of multipoint and single point scanning panretinal laser photocoagulation in non-proliferative diabetic retinopathy treatment
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作者 Yang-Zhou Zhang Hua Gong +2 位作者 Juan Yang Ji-Pu Bu Hui-Ling Yang 《World Journal of Diabetes》 SCIE 2024年第8期1734-1741,共8页
BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate... BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate the risk of progressing to proliferative diabetic retinopathy(PDR).AIM To compare the efficacy and safety of multi-spot vs single-spot scanning panretinal laser photocoagulation in NPDR patients.METHODS Forty-nine NPDR patients(86 eyes)treated between September 2020 and July 2022 were included.They were randomly allocated into single-spot(n=23,40 eyes)and multi-spot(n=26,46 eyes)groups.Treatment outcomes,including bestcorrected visual acuity(BCVA),central macular thickness(CMT),and mean threshold sensitivity,were assessed at predetermined intervals over 12 months.Adverse reactions were also recorded.RESULTS Energy levels did not significantly differ between groups(P>0.05),but the multi-spot group exhibited lower energy density(P<0.05).BCVA and CMT improvements were noted in the multi-spot group at one-month posttreatment(P<0.05).Adverse reaction incidence was similar between groups(P>0.05).CONCLUSION While energy intensity and safety were comparable between modalities,multi-spot scanning demonstrated lower energy density and showed superior short-term improvements in BCVA and CMT for NPDR patients,with reduced laser-induced damage. 展开更多
关键词 Panretinal laser photocoagulation Non-proliferative diabetic retinopathy Efficacy comparison Multipoint Single point Treatment assessment
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Global Research Progress on Municipal Waste and Future Prospect Based on the Cross-national Comparisons
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作者 ZHANG Yuxin LIU Xiaoqian +2 位作者 YAN Xiaoxia MA Sike MAO Weiyun 《Chinese Geographical Science》 SCIE CSCD 2024年第2期250-264,共15页
Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW ... Due to the acceleration of urbanization,the municipal waste(MW)problem has transformed into a global challenge for urb-an sustainability.To elucidate historical trends,current focal points,and future directions in MW research,we conducted a bibliometric analysis and employed knowledge graph visualization to scrutinize a total of 34212 articles,which were published between 1991 and 2021 in the Web of Science(WoS)core database.The results indicated that current major research themes encompass waste classifica-tion and recycling,waste management and public behavior,waste disposal methods and technologies,as well as environmental impact and evaluation.There has been a shift in the research focus from the environmental impacts of waste incineration to sustainable manage-ment related issues.A comparison of research from six typical countries revealed the differences in research priorities and techniques advantages.Scholars from the USA and Britain initiated MW research earlier than other countries and investigated management issues in depth,such as public behavior and willingness to pay.Meanwhile,Japanese,German,and Swedish scholars conducted extensive studies on advanced waste treatment technologies,such as disposal and recycling,risk assessment,and waste-to-energy techniques.Chinese scholars placed particular emphasis on end-of-pipe treatments and their associated environmental impacts.Hotspots and poten-tial future frontiers were identified by burst detection analysis.Keywords with high value of burst index(BI)worldwide are food waste and circular economy.Chinese scholars have put great efforts on waste environmental impact and its recycling technologies,while we’re expecting to further investigating vulnerable population.Furthermore,this study contributes to bridging the regional gap of scientific research among different countries and fostering international collaboration. 展开更多
关键词 BIBLIOMETRICS municipal waste(MW) CiteSpace hotspot prediction burst index(BI) SUSTAINABILITY cross-national comparison Web of Science(WoS)
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Optimization of Finned-Tube Heat Exchanger in a Gravity-Assisted Separated Heat Pipe
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作者 Yangyiming Rong Weitao Su +3 位作者 Shuai Wang Bowen Du Jianjian Wei Shaozhi Zhang 《Frontiers in Heat and Mass Transfer》 EI 2024年第4期1209-1229,共21页
Finned-tube heat exchanger(FTHE)is often used as an evaporator in commercial products of separated heat pipe(SHP).The working conditions of FTHE in gravity-assisted SHP are significantly different from those working i... Finned-tube heat exchanger(FTHE)is often used as an evaporator in commercial products of separated heat pipe(SHP).The working conditions of FTHE in gravity-assisted SHP are significantly different from those working in refrigerators and air conditioners.Although FTHE is widely used in commercial products of SHP,previous research on its characteristics is very limited.In this paper,a mathematical model for a SHP with FTHE as the evaporator and plate heat exchanger as the condenser is established and verified with experiments.Parametric analyses are carried out to investigate the influences of evaporator design parameters:air inlet velocity,number of tube rows,tube diameter,and fin pitch.With the increasing of air velocity,number of tube rows and tube diameter,and the decreasing of fin pitch,the heat transfer rate increases,while the energy efficiency ratio(EER)decreases monotonically.Using the total cost of the ten-year life cycle as the performance index,the structure parameters of the evaporator with a given heat transfer rate are optimized by the method of orthogonal experimental design.It is found that the total cost can differ as large as nearly ten times between groups.Among the three factors investigated,the number of tube rows has a significant impact on the total cost of the evaporator.With more tube rows,the total cost will be less.The impacts of fin pitch and tube diameter are insignificant.These results are of practical importance for the engineering design of FTHE in gravity-assisted SHP. 展开更多
关键词 separated heat pipe finned-tube heat exchanger GRAVITY OPTIMIZATION
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Comparison and Selection of Water Restoration Techniques for Artificial Landscape Lakes in Nantong City
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作者 Shengrong YAN Yuyue MA +2 位作者 Yi'an CHEN Jiafeng SUN Mingqing CHEN 《Agricultural Biotechnology》 2024年第3期90-92,95,共4页
As an important part of urban infrastructure,urban water system is of great and far-reaching significance for ensuring urban flood control and waterlogging safety,protecting ecological environment and building livable... As an important part of urban infrastructure,urban water system is of great and far-reaching significance for ensuring urban flood control and waterlogging safety,protecting ecological environment and building livable homes.Taking the urban water system of Nantong as an example,Nantong Water Resources Bureau issued R evision of Nantong Urban Water System Planning in 2017,and put forward the construction of the"two circles,eight lakes and nine veins"water system layout,giving new vitality to the urban water system.In view of problems existing in newly excavated artificial landscape lakes,such as fragile water ecosystem,strong eutrophication trend,poor environmental sensory effect and unsatisfactory water landscape effect,it is urgent to study the in-situ water ecological restoration technique of"algae-controlling zooplankton+submerged plant community"to build a"grass-type clear water"ecosystem for artificial landscape lakes,so as to improve the water sensory index and self-purification ability and finally realize the double improvement of"sensory effect and water quality"of artificial landscape lakes. 展开更多
关键词 Water body remediation technique Artificial landscape lake comparison and selection Nantong City
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Pharmacodynamic Experiment of Dachengqi Decoction and Separated Decoction on Incomplete Intestinal Obstruction in Rats
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作者 Jiangcun WEI Xiumei MA +5 位作者 Bing QING Meiyan QIU Qingmei DENG Hong LEI Zengyan YANG Zujie QIN 《Medicinal Plant》 2024年第4期107-110,共4页
[Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intesti... [Objectives]To investigate the effect and mechanism of Dachengqi Decoction and separated decoction on incomplete intestinal obstruction in rats.[Methods]80 healthy SD rats were selected to establish incomplete intestinal obstruction model by silk ligation.The dosage was 20 mL/kg for 3 d,and the damage index of ileocecal mucosa was analyzed;the morphology of ileocecal mucosa was observed by HE staining;the serum levels of IL-1α,IL-1β,IL-6,IL-18,Ach,NO,ET,IL-1,TNF-αand ultra-micro Na+-K+-ATPase were detected by ELISA.[Results]Compared with the model group,the mucosal damage index of Dachengqi Decoction and each separated decoction group decreased significantly(P<0.05);compared with the normal group and sham operation group,the serum level of IL-1,IL-6,TNF-αand other factors in the model group increased significantly(P<0.05);compared with the model group,the serum IL-1,IL-6 and TNF-αsecretion levels of rats in Dachengqi Decoction group and separated decoction group decreased(P<0.01).[Conclusions]Dachengqi Decoction and each separated decoction can effectively improve intestinal tissue pathological damage in the incomplete intestinal obstruction model rats,and reduce the inflammatory reaction in the rat body. 展开更多
关键词 Dachengqi Decoction separated decoction Incomplete intestinal obstruction Inflammatory factor
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Direct Pointwise Comparison of FE Predictions to StereoDIC Measurements:Developments and Validation Using Double Edge-Notched Tensile Specimen
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作者 Troy Myers Michael A.Sutton +2 位作者 Hubert Schreier Alistair Tofts Sreehari Rajan Kattil 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1263-1298,共36页
To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereoDIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is... To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereoDIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is developed.The procedure includes(a)conversion of the finite element data into a triangular mesh,(b)selection of a common coordinate system,(c)determination of the rigid body transformation to place both measurements and FEA data in the same system and(d)interpolation of the FEA nodal information to the same spatial locations as the StereoDIC measurements using barycentric coordinates.For an aluminum Al-6061 double edge notched tensile specimen,FEA results are obtained using both the von Mises isotropic yield criterion and Hill’s quadratic anisotropic yield criterion,with the unknown Hill model parameters determined using full-field specimen strain measurements for the nominally plane stress specimen.Using Hill’s quadratic anisotropic yield criterion,the point-by-point comparison of experimentally based full-field strains and stresses to finite element predictions are shown to be in excellent agreement,confirming the effectiveness of the field comparison process. 展开更多
关键词 StereoDIC spatial co-registration data transformation finite element simulations point-wise comparison of measurements and FEA predictions double edge notch specimen model validation
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Separate-layer balanced waterflooding development technology for thick and complex carbonate reservoirs in the Middle East
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作者 SONG Xinmin LI Yong +6 位作者 LI Fengfeng YI Liping SONG Benbiao ZHU Guangya SU Haiyang WEI Liang YANG Chao 《Petroleum Exploration and Development》 SCIE 2024年第3期661-673,共13页
Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic... Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs. 展开更多
关键词 the Middle East thick carbonate reservoir vertical heterogeneity concealed baffle and barrier sealing separated development units balanced waterflooding
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Does US Dollar Supply Trigger House Price Fluctuations?An International Comparison
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作者 Zihan Wang Yikun Huang 《Proceedings of Business and Economic Studies》 2024年第5期55-60,共6页
Cyclical fluctuations in asset prices are closely related to the overall stability of the macroeconomy and have thus become a significant topic in academic and professional exploration.Among these fluctuations,changes... Cyclical fluctuations in asset prices are closely related to the overall stability of the macroeconomy and have thus become a significant topic in academic and professional exploration.Among these fluctuations,changes in the supply of the U.S.dollar,the global reserve,and primary settlement currency have a broad and far-reaching impact on international financial markets.Since COVID-19,asset prices across various countries have shown differing trends due to fluctuations in the U.S.dollar supply.Housing prices,a key focus in asset pricing research,have been affected to varying degrees.This thesis utilizes seven house price indices from representative cities worldwide from 2020 to 2023 to compare the differential impacts across various countries using an empirical approach.The results indicate that the impact of the U.S.dollar money supply(M2)diminishes in a gradient from the U.S.to East Asia,and then to Europe. 展开更多
关键词 Dollar supply Quantitative easing Property prices International comparisons
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Comparison of the Development of CDMO at Home and Abroad and Its Enlightment to China
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作者 Zhao Meng Huang Zhe 《Asian Journal of Social Pharmacy》 2024年第3期244-250,共7页
Objective To analyze the development status of contract development manufacturing organization(CDMO)at home and abroad,and to make some suggestions for the development of CDMO in China.Methods The relevant literature ... Objective To analyze the development status of contract development manufacturing organization(CDMO)at home and abroad,and to make some suggestions for the development of CDMO in China.Methods The relevant literature was searched and reviewed,and the development status of CDMOs in the United States,France,Japan and China was compared from the aspects of market scale,development process,development focus,advantages and disadvantages,and policy support.Then,some suggestions for the development of CDMO enterprises in China were summarized.Results and Conclusion Through the comparison of CDMO development at home and abroad,it can be seen that China started CDMO late,there were many technical barriers and its globalization layout were not sufficient.However,the development trend was good and it focused on the field of chemical drugs and biological drugs to constantly develop innovative drugs.China needs to continuously improve its own technical capabilities to carry out innovative research.Therefore,cost reduction and efficiency increase will be the key elements for the development of CDMOs,and they are expected to have a rapid and comprehensive development in the future. 展开更多
关键词 CDMO current situation of enterprise development domestic and international comparison policy implications
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Separate支架在治疗胃十二指肠恶性梗阻中的应用 被引量:3
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作者 何旭 顾建平 +6 位作者 楼文胜 陈亮 苏浩波 Ji-Hoon Shin Jin-Oh Lim Tae-Hyuang Kim Ho-Young Song 《介入放射学杂志》 CSCD 2003年第6期431-435,共5页
目的 探讨Separate支架置入术在姑息性治疗不能手术的胃肠道恶性梗阻的可行性和有效性。方法  34例患者采用经口置入Separate支架治疗不能手术的恶性胃十二指肠梗阻。梗阻的原因分别是胃癌 1 1例、胰腺癌 1 2例、转移性肿瘤 3例、胆... 目的 探讨Separate支架置入术在姑息性治疗不能手术的胃肠道恶性梗阻的可行性和有效性。方法  34例患者采用经口置入Separate支架治疗不能手术的恶性胃十二指肠梗阻。梗阻的原因分别是胃癌 1 1例、胰腺癌 1 2例、转移性肿瘤 3例、胆道肿瘤 6例和十二指肠癌 2例。透视下分别将Separate支架的外层带膜支架和内层裸支架同轴重叠释放在狭窄病变处。结果 技术成功率为 97% ,未发生严重并发症。 33例患者胃肠道梗阻症状缓解或消失 ,在Separate支架置入后 ,患者进食能力评分平均从 3.8提高到 1 .2。随访期间未发现支架移位和肿瘤内生性生长等并发症 ,1例患者由于肿瘤浸润致支架近端梗阻复发 ,置入第 2枚支架。 展开更多
关键词 separate支架 胃十二指肠恶性梗阻 支架置入术 钡餐检查 介入治疗
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Comparison of stand structure and growth between artificial and natural forests of Pinus sylvestiris var. mongolica on sandy land 被引量:21
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作者 朱教君 范志平 +2 位作者 曾德慧 姜凤岐 MATSUZAKI Takeshi 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期103-111,共9页
Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in 揟hree North?regions (North, northwest and northeast of Chi... Mongolian pine (Pinus sylvestiris Linnaeus var. mongolica Litvinov) as a valuable conifer tree species has been broadly introduced to the sandy land areas in 揟hree North?regions (North, northwest and northeast of China), but many problems occurred in the earliest Mongolian pine plantations in Zhanggutai, Zhangwu County, Liaoning Province (ZZL). In order to clarify the reason, comprehensive investigations were carried out on differences in structure characteristics, growth processes and ecological factors between artificial stands (the first plantation established in ZZL in 1950s) and natural stands (the origin forests of the tree species in Honghuaerji, Inner Mongolia) on sandy land. The results showed that variation of diameter-class distributions in artificial stands and natural stands could be described by Weibull and Normal distribution models, respectively. Chapman-Richards growth model was employed to reconstruct the growth process of Mongolian pine based on the data from field investigation and stem analysis. The ages of maximum of relative growth rate and average growth rate of DBH, height, and volume of planted trees were 11, 22 years, 8, 15 years and 35, 59 years earlier than those of natural stand trees, respectively. In respect of the incremental acceleration of volume, the artificial and natural stands reached their maximum values at 14 years and 33 years respectively. The quantitative maturity ages of artificial stands and natural stands were 43 years and 102 years respectively. It was concluded that the life span of the Mongolian pine trees in natural stands was about 60 years longer than those in artificial stands. The differences mentioned above between artificial and natural Mongolian pine forests on sandy land were partially attributed to the drastic variations of ecological conditions such as latitude, temperature, precipitation, evaporation and height above sea level. Human beings' disturbances and higher density in plantation forest may be ascribed as additional reasons. Those results may be potentially useful for the management and afforestation of Mongolian pine plantations on sandy land in arid and semi-arid areas. 展开更多
关键词 Pinus sylvestiris var. mongolica Mongolian pine Sandy land comparison Growth model
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Solubility determination and comparison ofβ-HMX and RDX in two binary mixed solvents(acetonitrile+water,nitric acid+water)
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作者 Yuehua Yao Fan Wang +3 位作者 Yinguang Xu Zishuai Xu Lizhen Chen Jianlong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期238-249,共12页
In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in a... In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic method.The results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error root.Furthermore,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed solvent.The solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds. 展开更多
关键词 SOLUBILITY Octrahydro-1 3 5 7-tetranitro-1 3 5 7-tetrazocine Hexahydro-1 3 5-trinitro-1 3 5-triazine Separation Model Hydrogen bond
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Comparison of the City Water Consumption Short-Term Forecasting Methods 被引量:7
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作者 刘洪波 张宏伟 《Transactions of Tianjin University》 EI CAS 2002年第3期211-215,共5页
There are a lot of methods in city water consumption short-term forecasting both inside and outside the country. But among these methods there exist many advantages and shortcomings in model establishing, solving and ... There are a lot of methods in city water consumption short-term forecasting both inside and outside the country. But among these methods there exist many advantages and shortcomings in model establishing, solving and predicting accuracy, speed, applicability. This article draws lessons from other realm mature methods after many years′ study. It′s systematically studied and compared to predict the water consumption in accuracy, speed, effect and applicability among the time series triangle function method, artificial neural network method, gray system theories method, wavelet analytical method. 展开更多
关键词 city water consumption short-term forecasting method comparison APPLICABILITY
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Cross-cultural Comparison of Cognitive Structure and Behavior of Waterfront Landscape between Subjects of China,Japan and Britain 被引量:1
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作者 金华 金东来 王卓 《Journal of Landscape Research》 2012年第2期12-17,共6页
In order to explore the cultural value of waterfront in urban landscape,from the perspective of cross-cultural comparison psychology,the subjects from Britain,Japan and China have been surveyed to obtain their cogniti... In order to explore the cultural value of waterfront in urban landscape,from the perspective of cross-cultural comparison psychology,the subjects from Britain,Japan and China have been surveyed to obtain their cognitive structure and behavior on waterfront landscape.Based on the comparison of quantitative statistic results of life value,cognitive structure of waterfront space,and water-loving,a quantitative analysis has been conducted on the relevance between each factor by using Quantification Theory III.Then,it has analyzed the types and purpose of behavior in waterfront space,and the influence brought by cultural value difference. 展开更多
关键词 WATERFRONT LANDSCAPE Cognitive structure BEHAVIOR CROSS-CULTURAL comparison
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NEW PRINCIPLE FOR DIRECTIONAL COMPARISON CARRIER PROTECTION OF EHV TRANSMISSION LINES 被引量:1
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作者 王钢 李遥 +2 位作者 余晓丹 刘众仆 贺家李 《Transactions of Tianjin University》 EI CAS 1998年第2期6-10,共5页
The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave ch... The increasing scale and complexity of power systems require high performance and high reliability of power system protection.Protective relaying based on directional comparison with power line carrier or microwave channels is the most suitable protection scheme for long distance EHV transmission lines and is widely used in power systems.The key element of such protection is a directional relay used to discriminate the fault direction.In order to overcome the disadvantages of conventional directional relays,the authors of this paper put forward the directional comparison carrier protection based on the artificial neural network(ANN).The protection is extensively tested using electromagnetic transient program (EMTP) under various electric power system operating and fault conditions.It is proved that the directional comparison carrier protection based on ANN,which can recognize various fault patterns of the protected transmission line(such as fault direction,fault phases etc.)correctly in any kind of operating and fault conditions and the whole process,is satisfactory for EHV transmission line protection. 展开更多
关键词 artificial neural network EHV transmission line directional comparison carrier protection
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Economic Competitiveness of China and the US:Comparison,Dynamic Change and Global Position 被引量:2
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作者 倪鹏飞 王海波 《China Economist》 2017年第4期2-31,共30页
Research of competitiveness of China and the United States is of great significance to enhancing China's economic competitiveness and achieving the objective of national rejuvenation. By creating a competitiveness fr... Research of competitiveness of China and the United States is of great significance to enhancing China's economic competitiveness and achieving the objective of national rejuvenation. By creating a competitiveness framework and a system of heterogeneous indicators, this paper investigates the competitiveness of China and the US in terms of current status, historic change and global environment. Our research led to the following findings: core factors determine the level of competitiveness for China and the US; the national competitiveness of both countries is evolving towards structural homogeneity; and China and the US lead most countries in many common areas. China has the potential to overtake the US in competitiveness in the future. We suggest that China increase its competitiveness by promoting its advantages, addressing its weaknesses and focusing on core areas. 展开更多
关键词 national competitiveness comparison between China and the US factor eterogeneity
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