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Three decades and beyond:Breeding,biotech breakthroughs and future of China's GM insect-resistant cotton
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作者 Chengzhen Liang Shuangxia Jin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3243-3249,共7页
Cotton(Gossypium spp.)is a pivotal crop in the global textile industry,providing essential natural fibers.Additionally,cottonseed offers significant value as a source of oil and as feed for livestock(Huang et al.2021;... Cotton(Gossypium spp.)is a pivotal crop in the global textile industry,providing essential natural fibers.Additionally,cottonseed offers significant value as a source of oil and as feed for livestock(Huang et al.2021;Wen et al.2023).The sector,dependent on cotton,features a comprehensive value chain extending from the processing of fibers to the production of finished textiles,and it employs tens of millions of individuals(Dorward et al.1970). 展开更多
关键词 breakthrough COTTON finished
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Permeability Logging:A Breakthrough from 0 to1
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《Petroleum Exploration and Development》 SCIE 2024年第3期F0002-F0002,共1页
On March 3,2024,the prototype permeability logging instrument independently developed in China successfully completed its first downhole test in Ren 91 standard well in PetroChina Huabei Oilfield.In the open hole sect... On March 3,2024,the prototype permeability logging instrument independently developed in China successfully completed its first downhole test in Ren 91 standard well in PetroChina Huabei Oilfield.In the open hole section at a depth of 3925 metres and at a temperature of 148℃,the device collected high-quality permeability logging data.This marks a key technological breakthrough from 0 to 1 in permeability logging,and lays the foundation for the next step in developing a complete set of permeability logging equipment. 展开更多
关键词 LOGGING breakthrough instrument
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Early identification of scientific breakthroughs through outlier analysis based on research entities
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作者 Yang Zhao Mengting Zhang +1 位作者 Xiaoli Chen Zhixiong Zhang 《Journal of Data and Information Science》 CSCD 2024年第4期90-109,共20页
Purpose:To address the“anomalies”that occur when scientific breakthroughs emerge,this study focuses on identifying early signs and nascent stages of breakthrough innovations from the perspective of outliers,aiming t... Purpose:To address the“anomalies”that occur when scientific breakthroughs emerge,this study focuses on identifying early signs and nascent stages of breakthrough innovations from the perspective of outliers,aiming to achieve early identification of scientific breakthroughs in papers.Design/methodology/approach:This study utilizes semantic technology to extract research entities from the titles and abstracts of papers to represent each paper’s research content.Outlier detection methods are then employed to measure and analyze the anomalies in breakthrough papers during their early stages.The development and evolution process are traced using literature time tags.Finally,a case study is conducted using the key publications of the 2021 Nobel Prize laureates in Physiology or Medicine.Findings:Through manual analysis of all identified outlier papers,the effectiveness of the proposed method for early identifying potential scientific breakthroughs is verified.Research limitations:The study’s applicability has only been empirically tested in the biomedical field.More data from various fields are needed to validate the robustness and generalizability of the method.Practical implications:This study provides a valuable supplement to current methods for early identification of scientific breakthroughs,effectively supporting technological intelligence decision-making and services.Originality/value:The study introduces a novel approach to early identification of scientific breakthroughs by leveraging outlier analysis of research entities,offering a more sensitive,precise,and fine-grained alternative method compared to traditional citation-based evaluations,which enhances the ability to identify nascent breakthrough innovations. 展开更多
关键词 Scientific breakthroughs Outlier analysis Research entities
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Familial hypercholesterolemia:Current limitations and future breakthroughs
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作者 Ze Xiang Jia-Rui Li +2 位作者 Wei-Min Wan Shu-Hui Li Jian Wu 《World Journal of Experimental Medicine》 2024年第4期174-177,共4页
Familial hypercholesterolemia(FH)is characterized by elevated low-density lipoprotein cholesterol levels due to genetic mutations,presenting with xanthomas,corneal arch,and severe cardiovascular diseases.Early identif... Familial hypercholesterolemia(FH)is characterized by elevated low-density lipoprotein cholesterol levels due to genetic mutations,presenting with xanthomas,corneal arch,and severe cardiovascular diseases.Early identification,diagnosis,and treatment are crucial to prevent severe complications like acute myocardial infarction.Statins are the primary treatment,supplemented by Ezetimibe and proprotein convertase subtilisin/kexin type 9 inhibitors,though their effectiveness can be limited in severe cases.Over 90%of FH cases remain undiagnosed,and current treatments are often inadequate,underscoring the need for improved diagnostic and management systems.Future strategies include advancements in gene testing,precision medicine,and novel drugs,along with gene therapy approaches like AAV-mediated gene therapy and clustered regularly interspaced short palindromic repeats.Lifestyle modifications,including health education,dietary control,and regular exercise,are essential for managing FH and preventing related diseases.Research into FH-related gene mutations,especially LDLR,is critical for accurate diagnosis and effective treatment. 展开更多
关键词 Familial hypercholesterolemia Genetic mutations TREATMENT LIMITATIONS breakthroughs
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Big Fish, Big Market Controversies and breakthroughs in salmon farming in China
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作者 Guo Xixian 《China Report ASEAN》 2024年第10期43-47,共5页
On August 28,salmon industry insiders and consumers shared insights and analysis on the salmon market and consumption at the 7th Global Salmon Industry Development Summit.An important component of the 18th Shanghai In... On August 28,salmon industry insiders and consumers shared insights and analysis on the salmon market and consumption at the 7th Global Salmon Industry Development Summit.An important component of the 18th Shanghai International Fisheries Expo,the event attracted more than100 salmon farming companies from around the globe to exchange views on the current situation and future development of the industry. 展开更多
关键词 COMPANIES Market breakthrough
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Blasts Of Progress Xinjiang Bayi Iron and Steel's carbon reduction breakthroughs
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作者 Li Shimeng 《China Report ASEAN》 2024年第10期32-34,共3页
Facing dual challenges of climate change and energy crisis,the global iron and steel industry has been seeking to balance efficiency with energy conservation and environmental protection.Could the realities of blast f... Facing dual challenges of climate change and energy crisis,the global iron and steel industry has been seeking to balance efficiency with energy conservation and environmental protection.Could the realities of blast furnace operation possibly align with low-carbon circular development within China's iron and steel industry?Hydrogen-rich carbon circulating oxygen blast furnace (HyCROF)technology is gaining traction in the Chinese metallurgical industry. 展开更多
关键词 steel CARBON breakthrough
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A Review of the Research on the Influencing Factors of Enterprise Key Core Technology Breakthrough
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作者 Liangcan Liu Yuexian Zou 《Proceedings of Business and Economic Studies》 2024年第4期125-129,共5页
The breakthrough of key core technology is a theoretical and practical strategic issue to realize the rise of the country.This paper analyzes the concept of key core technology and its breakthrough and analyzes its ch... The breakthrough of key core technology is a theoretical and practical strategic issue to realize the rise of the country.This paper analyzes the concept of key core technology and its breakthrough and analyzes its characteristics.Based on the perspective of participants,this paper summarizes the influencing factors of key core technology breakthroughs in enterprises:internal and external enterprises,universities and scientific research institutions,and government.This paper expands the relevant research on key core technology breakthroughs and provides inspiration for enterprises to carry out key core technology research and breakthrough practices. 展开更多
关键词 Key core technology breakthrough Concept discrimination Technical features Influencing factors
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Suggestions on Improving China’s Breakthrough Therapy Designation System
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作者 Wang Zuguang Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第3期232-236,共5页
Objective To analyze the characteristics of breakthrough therapy designation(BTD)and its implementation in China,and to provide reference for the optimization of BTD system.Methods A comparative research method was us... Objective To analyze the characteristics of breakthrough therapy designation(BTD)and its implementation in China,and to provide reference for the optimization of BTD system.Methods A comparative research method was used to study the content and implementation effect of BTD system in China and the relevant policies and implementation of the same procedures of drug regulatory authorities in the United States,Japan and the European Union.Then,the differences in policies and implementation results among these countries were analyzed to provide suggestions for the implementation and optimization of this system in China.Results and Conclusion China’s BTD system is implemented late and a small number of drugs has been approved.At the same time,there are problems such as insufficient guidance and communication from the agency to applicants,a broad application condition,single review mode,and lack of full-time personnel.Both the agencies and the applicants have limited experience due to the short implementation time of BTD system in China.There are still some problems despite we have learned a lot from the experience of other drug regulatory agencies.Therefore,based on our national conditions,we should strengthen the guidance of evaluation agency to applicants,optimize the eligibility criteria of BTD system,introduce the rolling review,and increase the number of professional liaisons,which can accelerate the development and marketing process of drugs with obvious clinical value,and finally to address unmet medical need. 展开更多
关键词 breakthrough therapy designation(BTD) expedited program system optimization
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A Numerical Simulation Study of Temperature and Pressure Effects on the Breakthrough Pressure of CO_(2)in Unsaturated Low-permeability Rock Core 被引量:1
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作者 HU Zhikai LI Yi +6 位作者 LI Qi DIAO Yujie MA Xin LIU Hejuan FENG Guanhong WANG Fugang YU Qingchun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第3期911-924,共14页
Gas breakthrough pressure is a key parameter to evaluate the sealing capacity of caprock,and it also plays important roles in safety and capacity of CO_(2)geological storage.Based on the published experimental results... Gas breakthrough pressure is a key parameter to evaluate the sealing capacity of caprock,and it also plays important roles in safety and capacity of CO_(2)geological storage.Based on the published experimental results,we present numerical simulations on CO_(2)breakthrough pressure in unsaturated low-permeability rock under 9 multiple P-T conditions(which can keep CO_(2)in gaseous,liquid and supercritical states)and thus,a numerical method which can be used to accurately predict CO_(2)breakthrough pressure on rock-core scale is proposed.The simulation results show that CO_(2)breakthrough pressure and breakthrough time are exponential correlated with P-T conditions.Meanwhile,pressure has stronger effects on experimental results than that of temperature.Moreover,we performed sensitivity studies on the pore distribution indexλ(0.6,0.7,0.8,and 0.9)in van Genuchten-Muale model.Results show that with the increase ofλ,CO_(2)breakthrough pressure and breakthrough time both show decreasing trends.In other words,the larger the value ofλis,the better the permeability of the caprock is,and the worse the CO_(2)sealing capacity is.The numerical method established in this study can provide an important reference for the prediction of gas breakthrough pressure on rock-core scale and for related numerical studies. 展开更多
关键词 CO_(2)geological storage CO_(2)breakthrough pressure unsaturated low-permeability rock multiple P-T conditions numerical simulation
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Simulation of thermal breakthrough factors affecting carbonate geothermalto-well systems 被引量:1
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作者 Jia-xing Sun Gao-fan Yue Wei Zhang 《Journal of Groundwater Science and Engineering》 2023年第4期379-390,共12页
Fractures play a pivotal role in carbonate thermal storage systems,serving as primary hydraulic conductivity channels that significantly influence thermal breakthrough times and heat extraction efficiency in geotherma... Fractures play a pivotal role in carbonate thermal storage systems,serving as primary hydraulic conductivity channels that significantly influence thermal breakthrough times and heat extraction efficiency in geothermal-to-well systems.Their impact is critical for well placement and system life prediction.This paper focuses on a geothermal-to-well system within the carbonate reservoir of the Wumishan formation in the Rongcheng geothermal field,Xiong'an new area.It employs a combination of field tests and numerical simulations to determine the permeability of the reservoir and the evolution of fractures between wells.It also examines the influence of fracture width and roughness coefficient on the seepage and temperature fields under various injection scenarios and predicts thermal breakthrough times for production wells.The results show:Higher permeability is observed near well D16 compared to well D22 within the studied geothermal-to-well systems.Wider fractures between wells result in faster temperature decline in production wells.Lower injection flow rates lead to slower temperature reduction in injection wells.The use of roughness coefficients minimizes temperature variations in production wells.This study not only offers guidance for the development and utilization of the geothermal well system,but also contributes to a deeper understanding of the groundwater seepage and heat transfer process influenced by fractures. 展开更多
关键词 Geothermal recharge Influencing factor Thermal breakthrough Seepage field Temperature field
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Postvaccination breakthrough SARS-CoV-2 infections among adults in Malaysia and attitudes towards future vaccination
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作者 Praneetha Kumar Nair Kai Ern Koh +7 位作者 Christine Yvonne Bede Lee Ai Ren Natasha Mevuni Dinethma Mahanama Thin Mon Kyaw Htoo Htoo Kyaw Soe Soe Moe Kazi Majidur Rahaman Mila Nu Nu Htay 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2023年第7期296-304,共9页
Objective:To determine the frequency and severity of the breakthrough infections and the associated factors in Malaysia.Methods:This cross-sectional study was conducted among the adult general population in Malaysia w... Objective:To determine the frequency and severity of the breakthrough infections and the associated factors in Malaysia.Methods:This cross-sectional study was conducted among the adult general population in Malaysia who completed at least one dose of vaccination.The validated online questionnaires were used for data collection between December 2022 to February 2023.The participants were recruited by a convenient sampling method.The data were analysed by descriptive statistics,and logistic regression by using SPSS(Version 27).Qualitative data from open-ended questions were analysed as thematic analysis by using RQDA software.Results:A total of 524 participants'data were analyzed and 77.5%of them completed three doses of COVID-19 vaccination.Breakthrough infections after vaccination were reported in 57.3%of the participants.Age group of 18 and 30 years(aOR 2.32,95%CI 1.01-5.32)and other ethnicities(aOR 2.00,95%CI 1.02-3.93)significantly associated with the occurrence of breakthrough infections.A total of 35.5%of the participants were not willing to take another booster dose in the future because of their attitudes towards fear of long-term side effects,lack of trust to the vaccine,less susceptibility to severe infection,belief in natural immunity,and myths.Conclusions:Future public health policies and interventions should be focused on disseminating the information about safety of booster doses of vaccine,management and re-assurance of side effects,and targeted vaccination to the working(younger age group)and ethnic minorities. 展开更多
关键词 COVID-19 SARS CoV-2 breakthrough infection Vaccine MALAYSIA
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A breakthrough in cotton transformation technology
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作者 ZHANG Hong 《Journal of Cotton Research》 CAS 2023年第2期138-139,共2页
A new cotton transformation method was developed by Ge and colleagues at Institute of Cotton Research of Chinese Academy of Agricultural Sciences,and this work was published in a recent issue of the Journal of Integra... A new cotton transformation method was developed by Ge and colleagues at Institute of Cotton Research of Chinese Academy of Agricultural Sciences,and this work was published in a recent issue of the Journal of Integrative Plant Biology(Ge et al.2023;https://doi.org/10.1111/jipb.13427).This method is a milestone progress in the development of cotton transformation technologies,as it can be used to transform different genotypes and species of cotton such as Gossypium hirsutum,Gossypium barbadense,and Gossypium arboreum.This method is fast,user friendly,and the transformation efficiency is equivalent to or superior to other cotton transformation methods. 展开更多
关键词 TRANSFORMATION AGRICULTURAL breakthrough
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Diagnostic Method and Adaptability Analysis of Multiple Water Breakthroughs in Horizontal Well in Combined Well Pattern
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作者 Zheng Lv Meinan Wang +2 位作者 Guohao Zhang Rui Zhang Jianguo Liu 《Journal of Geoscience and Environment Protection》 2023年第5期150-158,共9页
The combined well pattern has been widely used in reservoir development, with a common pattern being a horizontal well in the center for oil production and multiple vertical wells around for water injection. For this ... The combined well pattern has been widely used in reservoir development, with a common pattern being a horizontal well in the center for oil production and multiple vertical wells around for water injection. For this type of well pattern, determining the horizontal well is affected by which injection wells, especially when the injecting water breaks through, accurately determining the direction of water inflow will provide an important basis for targeted water well measures. Based on the production performance data of horizontal wells, the semi logarithmic relationship curves of water-oil ratio, derivative water-oil ratio, and cumulative production were used for the first time to determine the breakthrough problem of water injection in the surrounding water injection wells of horizontal wells based on their response characteristics. The adaptability of this method under different influencing factors was analyzed. Introducing the parameter of cumulative production not only preserves the variation trend of the derivative of water-oil ratio with time, but also facilitates the processing of actual production data. 展开更多
关键词 Combined Well Pattern Multiple Water breakthroughs in Horizontal Derivative of Water-Oil Ratio
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NEXT-LEVEL TECHNOLOGY Construction of the Jakarta-Bandung High-Speed Railway required overcoming world-level challenges with myriad technological breakthroughs
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作者 Zhu Mengxiao 《China Report ASEAN》 2023年第10期30-32,共3页
When the sun rises,high-speed trains are already lined up for departure from Halim Station of the Jakarta-Bandung High-Speed Railway(HSR)in Indonesia.After seven years of preparation,the first Chinese-built high-speed... When the sun rises,high-speed trains are already lined up for departure from Halim Station of the Jakarta-Bandung High-Speed Railway(HSR)in Indonesia.After seven years of preparation,the first Chinese-built high-speed railway in Indonesia and the Southeast Asian region finally set off,ending ages of anticipation. 展开更多
关键词 NEXT breakthrough Speed
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Baseline HBV DNA level is the most important factor associated with virologic breakthrough in chronic hepatitis B treated with lamivudine 被引量:19
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作者 Hee Bok Chae Hie-Won Hann 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第30期4085-4090,共6页
AIM: To identify the factors associated with virologic breakthrough and to select a subgroup of patients who respond well to lamivudine without developing virologic breakthrough (VBT). METHODS: Of 79 patients who had ... AIM: To identify the factors associated with virologic breakthrough and to select a subgroup of patients who respond well to lamivudine without developing virologic breakthrough (VBT). METHODS: Of 79 patients who had received lamivudine therapy for 9-57 mo, 34 were HBeAg-positive and 45 were HBeAg-negative, 24 developed virologic breakthrough and 55 did not. Clinical and virologic factors were compared between the two groups. RESULTS: The median duration of therapy was 25 (9-57) mo. Virologic breakthrough was defined as a > 1 log HBV DNA increase following initial suppression. When several factors, including gender, duration of infection, baseline HBV DNA, and baseline ALT in HBeAg-positive chronic hepatitis patients were analyzed by logistic regression, the most important predictor of virologic breakthrough was the baseline HBV DNA (r2 = 0.12, P < 0.05). When HBeAg-postitive chronic hepatitis patients were divided into two groups by a point of 6.6 log HBV DNA, the incidence of virologic breakthough between two groups was significantly different. CONCLUSION: Lamivudine may remain an effective first line therapy for those HBeAg-positive patients with a baseline HBV DNA < 6.6 log10 copies/mL. 展开更多
关键词 Hepatitis B LAMIVUDINE Virologic breakthrough HBV DNA
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Research on Mechanisms of Steam Breakthrough and Profile Control Design for Steam Soaking Well 被引量:5
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作者 Liu Huiqing Zhang Hongling +2 位作者 Wang Shulin Wang Han Bao Shucheng 《Petroleum Science》 SCIE CAS CSCD 2006年第3期51-55,共5页
Scaled physical model tests for steam breakthrough were conducted based on the analysis of mechanisms and influence factors of steam breakthrough. Physical simulation results showed that at the initial steam breakthro... Scaled physical model tests for steam breakthrough were conducted based on the analysis of mechanisms and influence factors of steam breakthrough. Physical simulation results showed that at the initial steam breakthrough, preferential flow channels were formed in narrow sand packs and most residual oil left in these channels was immobile. This shortened the steam breakthrough time of follow-up steam flooding and decreased the increment of oil recovery efficiency. Steam breakthrough occurred easily for a smaller producer-injector spacing, and a bigger difference in physical properties between fluids and rock. Steam breakthrough is more likely to occur at a larger formation permeability (k), greater steam displacement velocity (u) and smaller producer-injector spacing (L). Steam breakthrough time is a function of the parameter group (uk/L), i.e. tb=3.2151 (uk/L)^-0.5142. A non piston-like displacement model was built based on steam breakthrough observation for a steam stimulated well in the Jinglou Oilfield, Henan Oilfield Company. The steam volume swept in different directions could be obtained from inter-well permeability capacity and breakthrough angle, and the steam swept pore volume (SSPV) was also determined. Numerical simulation showed that steam sweep efficiency reached its peak value when a slug of profile control agent (slug size 10%-15% SSPV) was set at one half of the inter-well spacing. Field test with 12.5% SSPV of profile control agents in the Jinglou Oilfield achieved success in sealing breakthrough channels and good production performance of adjacent producers. 展开更多
关键词 Heavy oil steam breakthrough scaled physical model profile control optimization design
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Revisiting normal perfusion pressure breakthrough in light of hemorrhage-induced vasospasm 被引量:4
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作者 Matthew D Alexander E Sander Connolly Philip M Meyers 《World Journal of Radiology》 CAS 2010年第6期230-232,共3页
Cerebral arteriovenous malformations(AVMs) have abnormally enlarged arteries and veins prone to spontaneous hemorrhage.Immediately following surgical excision of a cerebral AVM,even normal brain tissue surrounding the... Cerebral arteriovenous malformations(AVMs) have abnormally enlarged arteries and veins prone to spontaneous hemorrhage.Immediately following surgical excision of a cerebral AVM,even normal brain tissue surrounding the lesion is subject to hemorrhage,a phenomenon termed normal perfusion pressure breakthrough(NPPB) syndrome.According to this theory,arteries supplying cerebral AVMs become dilated and lose their capacity to dilate or constrict to autoregulate pressure.Acutely after removal of a cerebral AVM,excessive blood pressure in these arterial feeders can cause normal brain tissue to bleed.However,this theory remains controversial.We present a patient with a cerebral AVM that demonstrated cerebrovascular reactivity and argues against an assumption underlying the theory of NPPB syndrome. 展开更多
关键词 ARTERIOVENOUS MALFORMATION AUTOREGULATION Normal perfusion pressure breakthrough SUBARACHNOID HEMORRHAGE VASOSPASM
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Relationship between serum b2-microglobulin levels and virological breakthrough in HBeAg-negative chronic hepatitis B patients,under long-term treatment schedules including lamivudine 被引量:4
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作者 Ioannis S.Elefsiniotis Antonios Moulakakis +5 位作者 Konstantinos D.Pantazis Irene Glynou Ioannis Ketikoglou Elena Vezali Helen Kada Epameinondas Tsianos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第13期1922-1928,共7页
AIM: Predictive value of serum b2-microglobulin (b2m)levels for virological breakthrough (VB) in HBeAg-negative chronic hepatitis B (CHB) patients under long-term treatment schedules including lamivudine (LAM).METHODS... AIM: Predictive value of serum b2-microglobulin (b2m)levels for virological breakthrough (VB) in HBeAg-negative chronic hepatitis B (CHB) patients under long-term treatment schedules including lamivudine (LAM).METHODS: Serum b2m levels were calculated during treatment in 25 CHB patients under long-term LAM monotherapy (group A) and 12 patients under initial interferon plus LAM treatment followed by LAM monotherapy (group B), using the MEIA technology. We used Cox proportional hazard models in order to investigate the association between serum b2m levels and VB.RESULTS: Seven of 25 patients (28%), 9/25 (36%) and 14/25 (56%) from group A and 0/12, 2/12 (16.6%) and 3/12 (25%) from group B exhibited VB at months 12, 24 and 36 of treatment, respectively. All patients, from both groups, who did not show VB exhibited b2m elevation in mo 3. The duration of b2m elevation was significantly longer in the virological responder's subgroup from group A than the non-responder's one (7.3±2.6 vs 3.8±3.4 mo,P = 0.02). In comparison to group A patients whose b2m levels were increased at 3 mo, patients whose b2m levels were decreased had 4.6 times higher risk of experiencing VB (RR = 4.6, P = 0.024). When baseline variables were simultaneously included in the same Cox model, decreased b2m status was still associated with increased risk of VB (RR = 12.2, P = 0.03).CONCLUSION: In HBeAg-negative CHB patients under either long-term LAM monotherapy or initial combination treatment, serum b2m levels at 3 mo of treatment,compared to baseline ones, might be a predictor of risk for VB. 展开更多
关键词 Chronic hepatitis B LAMIVUDINE INTERFERON Virological breakthrough B2-microglobulin
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Numerical modeling of thermal breakthrough induced by geothermal production in fractured granite 被引量:5
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作者 Hejuan Liu Hongwei Wang +3 位作者 Hongwu Lei Liwei Zhang Mingxing Bai Lei Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第4期900-916,共17页
It is well known that the complicated channeling of fluid flow and heat transfer is strongly related with the intricate natural fracture system.However,it is still challenging to set up the fracture network model whic... It is well known that the complicated channeling of fluid flow and heat transfer is strongly related with the intricate natural fracture system.However,it is still challenging to set up the fracture network model which is strong heterogeneous.Compared with other methods(e.g.equivalent continuum model(ECM),discrete fracture model(DFM),and ECM-DFM),the fracture flow module in the COMSOL Multiphysics simulator is powerful in definition of fractures as the inner flow boundary existing in the porous media.Thus it is selected to simulate the fluid flow and heat transfer in the geothermal-developed fractured granite of Sanguliu area located at Liaodong Peninsula,Eastern China.The natural faults/fractures based on field investigation combined with the discrete fracture network(DFN)generated by the MATLAB are used to represent the two-dimensional geological model.Numerical results show that early thermal breakthrough occurs at the production well caused by quick flow of cold water along the highly connected fractures.Suitable hydraulic fracturing treatments with proper injection rates,locations,etc.can efficiently hinder the thermal breakthrough time in the natural fracture system.Large well spacing helps the long-term operation of geothermal production,but it is highly dependent on the geometrical morphology of the fracture network.The enhancement of reservoir properties at the near-well regions can also increase the geothermal production efficiency.The results in this study can provide references to achieve a sustainable geothermal exploitation in fractured granitic geothermal reservoirs or hot dry rocks at depth. 展开更多
关键词 Thermal breakthrough Discrete fracture network(DFN) Monte Carlo method Fracture aperture GRANITE
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Breakthrough of shallow shale gas exploration in Taiyang anticline area and its significance for resource development in Zhaotong, Yunnan Province, China 被引量:5
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作者 LIANG Xing XU Zhengyu +8 位作者 ZHANG Zhao WANG Weixu ZHANG Jiehui LU Huili ZHANG Lei ZOU Chen WANG Gaocheng MEI Jue RUI Yun 《Petroleum Exploration and Development》 2020年第1期12-29,共18页
Based on exploration and development results and evaluation of marine shale gas in South China in the past ten years, in view of the features of "high maturity, strong tectonic reformation and high shear stress&q... Based on exploration and development results and evaluation of marine shale gas in South China in the past ten years, in view of the features of "high maturity, strong tectonic reformation and high shear stress" of the shale in Zhaotong exploration zone in the Yunnan and Guizhou Plateau, as well as the key issues of long time diffusion and leakage of shallow shale gas, and the preservation conditions, the factors controlling shallow shale gas sweet spot and key zone selection evaluation technology of shale gas are investigated. From 2017 to 2018, the first significant exploration breakthrough was made in the Taiyang anticline at a buried depth of 700 to 2 000 m, discovering large-scale proved geological reserves of shallow shale gas. By examining the accumulation conditions and sweet spot control factors of the shallow shale gas in this area, it is found that the accumulation and productivity potential of shale gas in the mountainous area with complex structure outside basin are controlled by five factors:(1) The gas-rich area has weak tectonic reformation and good preservation conditions on the whole, taking on typical anticline trap occurrence mode.(2) The gas-rich area is in over-pressure state and high in shale gas content.(3) The gas-rich area has high quality shale and thus superior source rock condition.(4) The gas-rich area has high quality reservoirs dominated by class I.(5) The shale gas reservoir in the gas-rich area has high content of brittle minerals and small difference between maximum and minimum horizontal stresses which are conducive to hydraulic fracturing. The innovative practice and core technologies formed during the exploration and production capacity construction of shallow shale gas in the Zhaotong demonstration zone have great reference significance for shallow shale gas exploration and development in other areas. 展开更多
关键词 SHALLOW shale gas SILURIAN Longmaxi FORMATION Ordovician Wufeng FORMATION EXPLORATION breakthrough Taiyang ANTICLINE area Zhaotong area ANTICLINE
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