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Transjugular intrahepatic portosystemic shunt:A promising therapy for recompensation in cirrhotic patients 被引量:1
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作者 Ya-Ni Jin Wei Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第16期2285-2286,共2页
This is a retrospective study focused on recompensation after transjugular intrahepatic portosystemic shunt(TIPS)procedure.The authors confirmed TIPS could be a treatment for recompensation of patients with cirrhosis ... This is a retrospective study focused on recompensation after transjugular intrahepatic portosystemic shunt(TIPS)procedure.The authors confirmed TIPS could be a treatment for recompensation of patients with cirrhosis according to Baveno VII.The paper identified age and post-TIPS portal pressure gradient as independent predictors of recompensation in patients with decompensated cirrhosis after TIPS.These results need to be validated in a larger prospective cohort. 展开更多
关键词 Cirrhosis recompensation Transjugular intrahepatic portosystemic shunt Portal pressure gradient Predictor factor Baveno VII
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The effectiveness of physical activity interventions on blood pressure in children and adolescents:A systematic review and network meta-analysis
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作者 Mohamed A.Hassan Wanjiang Zhou +2 位作者 Mingyi Ye Hui He Zan Gao 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第5期699-708,共10页
Background:High blood pressure(BP)is a major contributor to mortality and cardiovascular diseases.Despite the known benefits of exercise for reducing BP,it is crucial to identify the most effective physical activity(P... Background:High blood pressure(BP)is a major contributor to mortality and cardiovascular diseases.Despite the known benefits of exercise for reducing BP,it is crucial to identify the most effective physical activity(PA)intervention.This systematic review and network meta-analysis(NMA)aimed to evaluate the available evidence on the effectiveness of various PA interventions for reducing BP and to determine their hierarchy based on their impact on BP.Methods:A search of PubMed,SPORTDiscus,PsycINFO,Web of Science,CINAHL,Cochrane,and Eric databases was conducted up to December 2022 for this systematic review and NMA.Randomized controlled trials and quasi-experimental studies targeting healthy children and adolescents aged 6-12 years old were included in this study.Only studies that compared controlled and intervention groups using PA or exercise as the major influence were included.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines.Three independent investigators performed the literature screening,data extraction,and risk of bias assessment.We used Bayesian arm-based NMA to synthesize the data.The primary outcomes were systolic BP and diastolic BP.We calculated the mean differences(MDs)in systolic BP and diastolic BP before and after treatment.Mean treatment differences were estimated using NMA and random-effect models.Results:We synthesized 27 studies involving 15,220 children and adolescents.PA combined with nutrition and behavior change was the most effective intervention for reducing both systolic BP and diastolic BP(MD=-8.64,95%credible interval(95%CI):-11.44 to-5.84;MD=-6.75,95%CI:-10.44 to-3.11),followed by interventions with multiple components(MD=-1.39,95%CI:-1.94 to-0.84;MD=-2.54,95%CI:-4.89 to-0.29).Conclusion:Our findings suggest that PA interventions incorporating nutrition and behavior change,followed by interventions with multiple components,are most effective for reducing both systolic BP and diastolic BP in children and adolescents. 展开更多
关键词 CHILDREN Diastolic blood pressure Physical activity Systolic blood pressure
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Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system
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作者 Nai-Liang Li Bin Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1305-1319,共15页
Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to ... Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop. 展开更多
关键词 Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging CORRELATION
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Control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method
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作者 M.Hajipour G.R.Ansarifar 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期145-154,共10页
Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor... Nuclear power plants exhibit non-linear and time-variable dynamics.Therefore,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(SCWR)is a fourth-generation conceptual reactor.In an SCWR,the non-linear dynamics of the reactor require a controller capable of control-ling the nonlinearities.In this study,a pressure-tube-type SCWR was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled simultaneously.In an SCWR,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power maneuvering.Reactor point kinetics equations with three groups of delayed neutrons were used in the simulation.Higher-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous studies.The controlled parameters were reactor power,steam temperature,and pressure.Notably,for these parameters,the PI controller had certain instabilities in the presence of disturbances.The classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering phenomenon.HOSMC was highly accurate and stable and had a small computational cost.In reality,it followed the desired values without oscillations and chattering. 展开更多
关键词 Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model
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Portal vein pulsatility:An important sonographic tool assessment of systemic congestion for critical ill patients
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作者 Stavros Dimopoulos Michael Antonopoulos 《World Journal of Cardiology》 2024年第5期221-225,共5页
In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility... In this editorial we comment on the article by Kuwahara et al,published in the recent issue of the World Journal of Cardiology.In this interesting paper,the authors showed a correlation between portal vein pulsatility ratio,examined by bedside ultrasonography,and prognosis of hospitalized patients with acute heart failure.Systemic congestion is being notoriously underdetected in the acutely ill population with conventional methods like clinical examination,biomarkers,central venous pressure estimation and X-rays.However,congestion should be a key therapeutic target due to its deleterious effects to end organ function and subsequently patient prognosis.Doppler flow assessment of the abdominal veins is gaining popularity worldwide,as a valuable tool in estimating comprehensively congestion and giving a further insight into hemodynamics and patient management. 展开更多
关键词 systemic congestion Organ perfusion Hemodynamics Central venous pressure Point of care ultrasound Venous excess ultrasound
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Ethics of Human Resources Management in the Cameroonian Health System, Medical Nomadism and the Ineffectiveness of the Fight against High Blood Pressure
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作者 Jean Ndibi Abanda Anicet Onana Akoa +2 位作者 Désiré Tchoffo Ulrich Dama Pierre Yassa Yoniene 《Health》 2024年第1期9-21,共13页
Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of sk... Context/objectives: The fight against Chronic Non-Communicable Diseases (NCDs) is a long-term undertaking, which requires available, motivated and well-managed human resources (HR). The administrative management of skills on both qualitative and quantitative levels is one of the essential functions of a health system. To better implement policies of fight against High Blood Pressure (HBP) and other chronic diseases, it is important to establish strategies to retain health personnel. This loyalty requires favorable working conditions and consideration of the contribution-reward couple. Good working conditions are likely to reduce the phenomenon of medical nomadism;conversely, poor HR management can contribute to their exodus towards exotic “green pastures”, thus leading to an additional crisis in the Cameroonian health system. The fight against HBP is a complex, multifaceted and multifactorial reality that requires appropriate management model for all types of resources mainly HR. The main objective of this research is to show the impact of poor management of human resources in Cameroon health system on medical nomadism and the ineffectiveness of the fight against High Blood Pressure. Method: A cross-sectional descriptive survey among five hundred (500) health facilities in the center region of Cameroon has been conducted. A stratified probabilistic technique has been used, and the number of health facilities to be surveyed has been determined using the “sample size estimation table” of Depelteau. The physical questionnaires have been printed and then distributed to data collectors. After data collection, the latter were grouped during processing in Excel sheets. The Chi-square test was used for data with a qualitative value and that of Kolmogorov-Sminorf for data with a quantitative value to assess the normality and reliability of data. The Crochach’s Alpha reliability test allowed us to have a summary of the means and variances and then to search for intragroup correlations between variables. Descriptive analysis was possible with the XLSTAT 2016 software. Results: 43.60% of Health Facilities (HF) managers were unqualified. 82.20% of HF managers have staff in a situation of professional insecurity. They are mainly contractual (49.00), decision-making agents (24.40%), casual agents (08.80). The proportion of unstable personnel is average of 22.00% and very unstable, 12.00%. 展开更多
关键词 ETHICS Human Resources Management Cameroonian Health system Medical Nomadism Ineffectiveness High Blood Pressure
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Experimental models of high-risk bowel anastomosis in rats:A systematic review
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作者 Georgios Ntampakis Manousos-Georgios Pramateftakis +8 位作者 Elissavet Anestiadou Stefanos Bitsianis Orestis Ioannidis Chryssa Bekiari George Koliakos Maria Karakota Anastasia Tsakona Angeliki Cheva Stamatios Angelopoulos Fourth 《World Journal of Experimental Medicine》 2024年第2期114-131,共18页
BACKGROUND Anastomotic leaks remain one of the most dreaded complications in gastrointestinal surgery causing significant morbidity,that negatively affect the patients’quality of life.Experimental studies play an imp... BACKGROUND Anastomotic leaks remain one of the most dreaded complications in gastrointestinal surgery causing significant morbidity,that negatively affect the patients’quality of life.Experimental studies play an important role in understanding the pathophysiological background of anastomotic healing and there are still many fields that require further investigation.Knowledge drawn from these studies can lead to interventions or techniques that can reduce the risk of anastomotic leak in patients with high-risk features.Despite the advances in experimental protocols and techniques,designing a high-quality study is still challenging for the investigators as there is a plethora of different models used.AIM To review current state of the art for experimental protocols in high-risk anastomosis in rats.METHODS This systematic review was performed according to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.To identify eligible studies,a comprehensive literature search was performed in the electronic databases PubMed(MEDLINE)and Scopus,covering the period from conception until 18 October 2023.RESULTS From our search strategy 102 studies were included and were categorized based on the mechanism used to create a high-risk anastomosis.Methods of assessing anastomotic healing were extracted and were individually appraised.CONCLUSION Anastomotic healing studies have evolved over the last decades,but the findings are yet to be translated into human studies.There is a need for high-quality,well-designed studies that will help to the better understanding of the pathophysiology of anastomotic healing and the effects of various interventions. 展开更多
关键词 High-risk anastomosis RATS Experimental models BOWEL COLON Anastomotic leak Colon resection Inflammatory bowel disease Intra-abdominal sepsis Bursting pressure
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Diamond growth in a high temperature and high pressure Fe–Ni–C–Si system:Effect of synthesis pressure 被引量:1
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作者 刘杨 王志文 +5 位作者 李博维 赵洪宇 王胜学 陈良超 马红安 贾晓鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第12期602-608,共7页
Pressure is one of the necessary conditions for diamond growth.Exploring the influence of pressure on growth changes in silicon-doped diamonds is of great value for the production of high-quality diamonds.This work re... Pressure is one of the necessary conditions for diamond growth.Exploring the influence of pressure on growth changes in silicon-doped diamonds is of great value for the production of high-quality diamonds.This work reports the morphology,impurity content and crystal quality characteristics of silicon-doped diamond crystals synthesized under different pressures.Fourier transform infrared spectroscopy shows that with the increase of pressure,the nitrogen content in the C-center inside the diamond crystal decreases.X-ray photoelectron spectroscopy test results show the presence of silicon in the diamond crystals synthesized by adding silicon powder.Raman spectroscopy data shows that the increase in pressure in the Fe-Ni-C-Si system shifts the Raman peak of diamonds from 1331.18 cm^(-1)to 1331.25 cm^(-1),resulting in a decrease in internal stress in the crystal.The half-peak width decreased from 5.41 cm^(-1)to 5.26 cm^(-1),and the crystallinity of the silicon-doped diamond crystals improved,resulting in improved quality.This work provides valuable data that can provide a reference for the synthesis of high-quality silicon-doped diamonds. 展开更多
关键词 silicon-doped diamond crystal quality pressure effect nitrogen content
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Management of sepsis in a cirrhotic patient admitted to the intensive care unit:A systematic literature review 被引量:1
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作者 Nkola Ndomba Jonathan Soldera 《World Journal of Hepatology》 2023年第6期850-866,共17页
BACKGROUND Sepsis is a severe medical condition that occurs when the body's immune system overreacts to an infection,leading to life-threatening organ dysfunction.The"Third international consensus definitions... BACKGROUND Sepsis is a severe medical condition that occurs when the body's immune system overreacts to an infection,leading to life-threatening organ dysfunction.The"Third international consensus definitions for sepsis and septic shock(Sepsis-3)"defines sepsis as an increase in sequential organ failure assessment score of 2 points or more,with a mortality rate above 10%.Sepsis is a leading cause of intensive care unit(ICU)admissions,and patients with underlying conditions such as cirrhosis have a higher risk of poor outcomes.Therefore,it is critical to recognize and manage sepsis promptly by administering fluids,vasopressors,steroids,and antibiotics,and identifying and treating the source of infection.AIM To conduct a systematic review and meta-analysis of existing literature on the management of sepsis in cirrhotic patients admitted to the ICU and compare the management of sepsis between cirrhotic and non-cirrhotic patients in the ICU.METHODS This study is a systematic literature review that followed the PRISMA statement's standardized search method.The search for relevant studies was conducted across multiple databases,including PubMed,Embase,Base,and Cochrane,using predefined search terms.One reviewer conducted the initial search,and the eligibility criteria were applied to the titles and abstracts of the retrieved articles.The selected articles were then evaluated based on the research objectives to ensure relevance to the study's aims.RESULTS The study findings indicate that cirrhotic patients are more susceptible to infections,resulting in higher mortality rates ranging from 18%to 60%.Early identification of the infection source followed by timely administration of antibiotics,vasopressors,and corticosteroids has been shown to improve patient outcomes.Procalcitonin is a useful biomarker for diagnosing infections in cirrhotic patients.Moreover,presepsin and resistin have been found to be reliable markers of bacterial infection in patients with decompensated liver cirrhosis,with similar diagnostic performance compared to procalcitonin.CONCLUSION This review highlights the importance of early detection and management of infections in cirrhosis patients to reduce mortality.Therefore,early detection of infection using procalcitonin test and other biomarker as presepsin and resistin,associated with early management with antibiotics,fluids,vasopressors and low dose corticosteroids might reduce the mortality associated with sepsis in cirrhotic patients. 展开更多
关键词 SEPSIS Septic shock CIRRHOSIS Sequential organ failure assessment score Mean arterial pressure Intensive care unit
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An Analysis of the Static and Dynamic Behavior of the Hydraulic Compensation System of a Multichannel Valve
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作者 Jikang Xu Ruichuan Li +5 位作者 Yi Cheng Yanchao Li Junru Yang Chenyu Feng Xinkai Ding Huazhong Zhang 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1817-1836,共20页
Electro-hydraulic proportional valve is the core control valve in many hydraulic systems used in agricultural and engineering machinery.To address the problem related to the large throttling losses and poor stability ... Electro-hydraulic proportional valve is the core control valve in many hydraulic systems used in agricultural and engineering machinery.To address the problem related to the large throttling losses and poor stability typically associated with these valves,here,the beneficial effects of a triangular groove structure on the related hydraulic response are studied.A mathematical model of the pressure compensation system based on the power-bond graph method is introduced,and the AMESim software is used to simulate its response.The results show that the triangular groove structure increases the jet angle and effectively compensates for the hydrodynamic force.The steady-state differential pressure at the valve port of the new pressure compensation structure was 0.65 MPa.Furthermore,experimental results show that the pressure difference at the main valve port is 0.73 MPa,and that the response time is less than 0.2 s.It is concluded that the new compensation structure has good pressure compensation response characteristics. 展开更多
关键词 Electrohydraulic proportional valve spool shape pressure compensation valve port differential pressure response time
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An ultrafast spectroscopy system for studying dynamic properties of superconductors under high pressure and low temperature conditions
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作者 朱健 李叶西 +9 位作者 冯登满 苏德鹏 范东牛 杨松 赵辰晓 赵高扬 李亮 李芳菲 王英惠 周强 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期608-613,共6页
An ultrafast pump-probe spectroscopy system combined with a cryogenic diamond anvil cell(DAC) instrument is developed to investigate the photo-excitation dynamic properties of condensed materials under low temperature... An ultrafast pump-probe spectroscopy system combined with a cryogenic diamond anvil cell(DAC) instrument is developed to investigate the photo-excitation dynamic properties of condensed materials under low temperature and high pressure(LTHP) conditions.The ultrafast dynamics study is performed on Bi_(2)Sr_(2)CaCu_(2)O_(8+δ)(Bi-2212) thin film under LTHP conditions.The superconducting(SC) phase transition has been observed by analyzing the ultrafast dynamics of Bi-2212 as a function of pressure and temperature.Our results suggest that the pump-probe spectroscopy system combined with a cryogenic DAC instrument is an effective method to study the physical mechanism of condensed matter physics at extreme conditions,especially for the SC phase transition. 展开更多
关键词 high pressure ultrafast spectroscopy SUPERCONDUCTING phase transition
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Pressure-induced stable structures and physical properties of Sr–Ge system
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作者 韩帅 段帅 +4 位作者 刘云仙 王超 陈欣 孙海瑞 刘晓兵 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期398-405,共8页
We have systematically investigated the structures of Sr-Ge system under pressures up to 200 GPa and found six stable stoichiometric structures,they being Sr_(3)Ge,Sr_(2)Ge,SrGe,SrGe_(2),SrGe_(3),and SrGe_(4).We demon... We have systematically investigated the structures of Sr-Ge system under pressures up to 200 GPa and found six stable stoichiometric structures,they being Sr_(3)Ge,Sr_(2)Ge,SrGe,SrGe_(2),SrGe_(3),and SrGe_(4).We demonstrate the interesting structure evolution behaviors in Sr-Ge system with the increase of germanium content,Ge atoms arranging into isolated anions in Sr_(3)Ge,chains in Sr_(2) Ge,square units in SrGe,trigonal units and hexahedrons in SrGe_(2),cages in SrGe_(3),hexagons and Geg rings in SrGe_(4).The structural diversity produces various manifestations of electronic structures,which is of benefit to electrical transportation.Among them,these novel phases with metallic structures show superconductivity(maximum T_(c)~8.94 K for Pmmn Sr_(3)Ge).Notably,the n-type semiconducting Pnma SrGe_(2) structure exhibits high Seebeck coefficient and excellent electrical conductivity along the y direction,leading to a high ZT value up to 1.55 at 500 K,which can be potential candidates as high-performance thermoelectrics.Our results will enable the development of fundamental science in condensed matter physics and potential applications in novel electronics or thermoelectric materials. 展开更多
关键词 high pressure first-principle calculation germanium–strontium compounds SUPERCONDUCTIVITY thermoelectric property
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Development of a pressure coring system for the investigation of deep underground exploration
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作者 Da Guo Ling Chen +8 位作者 Zhongya Zhou Dingming Wang Yiwei Zhang Xun Yang Xin Fang Xiaojun Wang Heping Lu Lin Dai Heping Xie 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第11期1351-1364,共14页
To provide a more accurate evaluation of the scale of deep underground resources,a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyse... To provide a more accurate evaluation of the scale of deep underground resources,a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyses and numerical simulation.The designed pressure coring system can obtain cores with length of 3 m and diameter of 50 mm at 70 MPa.The results of the ball-drop operation experiment demonstrate that differential motion assembly can effectively cut a safety pin by applying a tensile force of 4852 N,and it can lift the core tube through the center pole to complete a series of mechanical actions to seal the pressure.Additionally,by maintaining pressures at 70 MPa for 30 min,the pressure sealing capacity of the system was proven.Furthermore,a core sample with a diameter of 50 mm was obtained through a core drilling experiment and the coring performance of the pressure coring system was verified.This study can not only enrich the existing onshore coring technology but also provide a theoretical guide and design criteria for the development of similar pressure coring systems to meet the demand for deeper underground exploration. 展开更多
关键词 Underground exploration In-situ coring Pressure coring Oil and gas production
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Non-Contact Physiological Measurement System for Wearing Masks During the Epidemic
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作者 Shu-Yin Chiang Dong-Ye Wu 《Computers, Materials & Continua》 SCIE EI 2023年第5期2509-2526,共18页
Physiological signals indicate a person’s physical and mental state at any given time.Accordingly,many studies extract physiological signals from the human body with non-contact methods,and most of them require facia... Physiological signals indicate a person’s physical and mental state at any given time.Accordingly,many studies extract physiological signals from the human body with non-contact methods,and most of them require facial feature points.However,under COVID-19,wearing a mask has become a must in many places,so how non-contact physiological information measurements can still be performed correctly even when a mask covers the facial information has become a focus of research.In this study,RGB and thermal infrared cameras were used to execute non-contact physiological information measurement systems for heart rate,blood pressure,respiratory rate,and forehead temperature for peoplewearing masks due to the pandemic.Using the green(G)minus red(R)signal in the RGB image,the region of interest(ROI)is established in the forehead and nose bridge regions.The photoplethysmography(PPG)waveforms of the two regions are obtained after the acquired PPG signal is subjected to the optical flow method,baseline drift calibration,normalization,and bandpass filtering.The relevant parameters in Deep Neural Networks(DNN)for the regression model can correctly predict the heartbeat and blood pressure.In addition,the temperature change in the ROI of the mask after thermal image processing and filtering can be used to correctly determine the number of breaths.Meanwhile,the thermal image can be used to read the temperature average of the ROI of the forehead,and the forehead temperature can be obtained smoothly.The experimental results show that the above-mentioned physiological signals of a subject can be obtained in 6-s images with the error for both heart rate and blood pressure within 2%∼3%and the error of forehead temperature within±0.5°C. 展开更多
关键词 PPG DNN heart rate blood pressure prediction face mask
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Hemodynamic Profiling Using a Cardiac Index–Systemic Vascular Resistance Plot in Patients with Fontan Circulation
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作者 Yuki Kawasaki Takeshi Sasaki Daisuke Kobayashi 《Congenital Heart Disease》 SCIE 2023年第4期431-445,共15页
Background: Elevated Fontan pressure (FP) alone cannot fully predict clinical outcomes. We hypothesized thathemodynamic profiling using a cardiac index (CI)-systemic vascular resistance (SVR) plot could characterize c... Background: Elevated Fontan pressure (FP) alone cannot fully predict clinical outcomes. We hypothesized thathemodynamic profiling using a cardiac index (CI)-systemic vascular resistance (SVR) plot could characterize clinicalfeatures and predict the prognosis of post-Fontan patients. Methods: We included post-Fontan patients whounderwent cardiac catheterization at age < 10 years. Patients were classified into four categories: A, CI ≥ 3, SVRindex (SVRI) ≥ 20;B, CI < 3, SVRI ≥ 20;C, CI ≥ 3, SVRI < 20;and D, CI < 3, SVRI < 20. The primary outcome wasfreedom from the combined endpoint: new onset of protein-losing enteropathy or plastic bronchitis, heart transplant,and death. Clinical and hemodynamic variables and freedom from the endpoint were compared betweenthe hemodynamic categories and outcome predictors were evaluated. Results: Eighty-three patients wereincluded. Median follow-up was 5.3 years. Category A/B/C/D consisted of 4/15/53/11 patients, respectively. Allthe patients in category A were New York Heart Association I/II and had a significantly lower pulmonary vascularresistance index (PVRI). Patients in category C had lower pulmonary/systemic blood flow. Patients in category Dhad a higher PVRI and had the poorest freedom from the endpoint (44% at 5 years). Elevated FP and category Dwere outcome predictors. Conclusions: CI-SVR plots was a novel adjunctive method for Fontan hemodynamicprofiling. 展开更多
关键词 Cardiac index systemic vascular resistance perfusion pressure hemodynamic category fontan circulation PROGNOSIS
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Pre-transjugular-intrahepatic-portosystemic-shunt measurement of hepatic venous pressure gradient and its clinical application: A comparison study
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作者 Xi-Xuan Wang Xiao-Chun Yin +11 位作者 Li-Hong Gu Hui-Wen Guo Yang Cheng Yan Liu Jiang-Qiang Xiao Yi Wang Wei Zhang Xiao-Ping Zou Lei Wang Ming Zhang Yu-Zheng Zhu-Ge Feng Zhang 《World Journal of Gastroenterology》 SCIE CAS 2023年第22期3519-3533,共15页
BACKGROUND It is controversial whether transjugular intrahepatic portosystemic shunt(TIPS)placement can improve long-term survival.AIM To assess whether TIPS placement improves survival in patients with hepaticvenous-... BACKGROUND It is controversial whether transjugular intrahepatic portosystemic shunt(TIPS)placement can improve long-term survival.AIM To assess whether TIPS placement improves survival in patients with hepaticvenous-pressure-gradient(HVPG)≥16 mmHg,based on HVPG-related risk stratification.METHODS Consecutive variceal bleeding patients treated with endoscopic therapy+nonselectiveβ-blockers(NSBBs)or covered TIPS placement were retrospectively enrolled between January 2013 and December 2019.HVPG measurements were performed before therapy.The primary outcome was transplant-free survival;secondary endpoints were rebleeding and overt hepatic ence-phalopathy(OHE).RESULTS A total of 184 patients were analyzed(mean age,55.27 years±13.86,107 males;102 in the EVL+NSBB group,82 in the covered TIPS group).Based on the HVPG guided risk stratification,70 patients had HVPG<16 mmHg,and 114 patients had HVPG≥16 mmHg.The median follow-up time of the cohort was 49.5 mo.There was no significant difference in transplant-free survival between the two treatment groups overall(hazard ratio[HR],0.61;95%confidence interval[CI]:0.35-1.05;P=0.07).In the high-HVPG tier,transplant-free survival was higher in the TIPS group(HR,0.44;95%CI:0.23-0.85;P=0.004).In the low-HVPG tier,transplantfree survival after the two treatments was similar(HR,0.86;95%CI:0.33-0.23;P=0.74).Covered TIPS placement decreased the rate of rebleeding independent of the HVPG tier(P<0.001).The difference in OHE between the two groups was not statistically significant(P=0.09;P=0.48).CONCLUSION TIPS placement can effectively improve transplant-free survival when the HVPG is greater than 16 mmHg. 展开更多
关键词 Hepatic venous pressure gradient Transjugular intrahepatic portosystemic shunts CIRRHOSIS Variceal rebleeding SURVIVAL
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Abnormal Systemic and Ocular Responses to the Valsalva Manoeuvre in Primary Open-Angle Glaucoma:A Case for Autonomic Failure?
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作者 Bin-bin LIU Bo-wen ZHAO +3 位作者 Fei-peng WU Tian HU Yin ZHAO Hong ZHANG 《Current Medical Science》 SCIE CAS 2023年第2期376-383,共8页
Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the V... Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the Valsalva manoeuvre(VM),between POAG patients and normal subjects.Methods Forty POAG and forty control subjects were subjected to the VM.Systemic and ocular parameters were measured at baseline,phase 2,and phase 4 of the VM(VM2 and VM4),where VM2 and VM4 are sympathetic and parasympathetic nervous activation states,respectively.Heart rate variability was used to assess the autonomic nervous activity,among which the high-frequency component(HF)and the low-frequency(LF)/HF ratio were used as indices of parasympathetic and sympathetic activation,respectively.Results POAG patients demonstrated higher sympathetic activation(LF/HF ratio median:2.17 vs.1.53,P=0.000)than controls at baseline and exhibited attenuated sympathetic and parasympathetic responses(a smaller change in LF/HF and HF values)during the VM than controls.During VM,the intraocular pressure(IOP),mean blood pressure(MAP),mean ocular perfusion pressure(MOPP),and the Schlemm’s canal area(SCAR)increased from baseline to VM2 and then decreased from VM2 to VM4 in both the POAG and control groups(all P<0.05).However,when we compared the changes above,the fluctuations in IOP,MAP,and MOPP were more pronounced in POAG than in controls(all P<0.05),while the changes in amplitudes of SCAR were smaller in POAG(P<0.05).Furthermore,from VM2 to VM4,the choroid thickness(ChT)in the POAG group was significantly decreased,while it was unchanged in normal subjects(P=0.258).A regression analysis showed a significant correlation of the baseline LF/HF with IOP change values(ΔIOP)from baseline to VM2 in POAG(R^(2)=0.147,P=0.014).Conclusion Patients with POAG showed more pronounced fluctuations in IOP,MAP,MOPP and ChT during the VM than controls.These reactions could be associated with autonomic dysfunction in POAG. 展开更多
关键词 primary open-angle glaucoma Valsalva manoeuvre autonomic dysfunction intraocular pressure Schlemm’s canal
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Carbon dioxide partial pressure and its diffusion flux in karst surface aquatic ecosystems:a review
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作者 Xingxing Cao Qixin Wu +1 位作者 Wanfa Wang Pan Wu 《Acta Geochimica》 EI CAS CSCD 2023年第5期943-960,共18页
Carbon dioxide(CO_(2))emissions from aquatic ecosystems are an important component of the karst carbon cycle process and also a key indicator for assessing the effect of karst carbon sinks.This paper reviewed the CO_(... Carbon dioxide(CO_(2))emissions from aquatic ecosystems are an important component of the karst carbon cycle process and also a key indicator for assessing the effect of karst carbon sinks.This paper reviewed the CO_(2)partial pressure(pCO_(2))and its diffusion flux(FCO_(2))in karst surface aquatic ecosystems,mainly rivers,lakes,and reservoirs,and their influencing factors summarized the methods for monitoring CO_(2)emissions in karst aquatic ecosystems and discussed their adaptation conditions in karst areas.The pCO_(2)and FCO_(2)decreased in the order of rivers>reservoirs>lakes,and the values in karst lakes were eventually significantly lower than those in global lakes.The pCO_(2)and FCO_(2)of karst aquatic ecosystems had patterns of variation with diurnal,seasonal,water depth and hydrological cycles,and spatial and temporal hetero-geneity.The sources of CO_(2)in karst waters are influenced by both internal and external sources,and the key spatial and temporal factors affecting the CO_(2)emissions from karst rivers,lakes,and reservoirs were determined in terms of physicochemical indicators,biological factors,and bio-genic elements;additionally,the process of human activity interference on CO_(2)emissions was discussed.Finally,a conceptual model illustrating the impacts of urban devel-opment,agriculture,mining,and dam construction on the CO_(2)emissions at the karst surface aquatic ecosystem is presented.Meanwhile,based on the disadvantages existing in current research,we proposed several important research fields related to CO_(2)emissions from karst surface aquatic ecosystems. 展开更多
关键词 Karst area RIVER LAKE RESERVOIR Partial pressure of CO_(2) CO_(2)diffusion flux
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Systemic Capillary Leak Syndrome Secondary to COVID-19 Infection: Case Report
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作者 Mariam El Galiou N’mili Manal +4 位作者 Benamar Loubna Ouzeddoun Naima Bayahia Rabia Madani Naoufel Bouattar Tarik 《Open Journal of Nephrology》 2023年第3期226-233,共8页
Introduction: Systemic capillary leak syndrome (SCLS) is an increasingly recognized rare syndrome. Its diagnosis is suggested by the occurrence of edema with arterial hypotension, hemoconcentration, and paradoxical hy... Introduction: Systemic capillary leak syndrome (SCLS) is an increasingly recognized rare syndrome. Its diagnosis is suggested by the occurrence of edema with arterial hypotension, hemoconcentration, and paradoxical hypoalbuminemia. SCLS can be idiopathic (Clarkson syndrome) or secondary. Secondary SCLS (SSCLS) is mainly triggered by infections (especially viruses), drugs (antitumor therapy), malignancies, and inflammatory diseases. We report a case of systemic capillary leak syndrome secondary to the COVID-19 infection. Observation: A 74-year-old chronic smoker with no particular history was initially admitted to the intensive care unit (ICU) with a picture of respiratory distress secondary to a COVID-19 infection with favorable evolution, hence his transfer to the emergency services. On Day 8 of hospitalization, following the installation of arterial hypotension, not responding to filling, associated with hypoalbuminemia, and generalized edematous syndrome, and in the absence of any other explanation for this clinical picture, a SCLS secondary to COVID-19 infection was suggested. On the balance sheet, after the discovery of acute renal failure, serum creatinine went from 7.9 mg/l to 16.6 mg/l with microalbuminuria at 420 mg/24h and leukocyturia at 20 elements/mm<sup>3</sup> without germ-evoked tubulointerstitial nephritis (TIN) secondary to a viral infection with COVID-19. The evolution was marked by the spontaneous regression of the edema and the normalization of the blood pressure figures. Discussion: The classic triad combining hypotension, hemoconcentration, and hypoalbuminemia suggests the diagnosis of SCLS once all other causes of shock have been ruled out. Hemoconcentration is less constant in SSCLS than in ISCLS. This is the case with our patient. The exact pathophysiological process of SCLS is largely unknown. Viral infections are the most common infectious cause of SCLS. The kidneys are the second-most common organs affected by the SARS-Cov-2 coronavirus infection. The presence of nephritis can be used as an indicator of SCLS, which can be a predictor of serious complications such as fluid overload, respiratory failure, and the need for ICU admission. Conclusion: In the event of COVID-19 infection, the appearance of hypotension and hypoalbuminemia with the gradual onset of generalized edema should suggest SCLS. The establishment of close monitoring is mandatory, given the risk of fatal evolution. Fortunately, for our patient, the evolution was favorable. 展开更多
关键词 HEMOCONCENTRATION Low Blood Pressure COVID-19 Tubulointerstitial Nephritis
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Propagation Characteristics of Ultrasonic Guided Waves in Grouted Rockbolt Systems with Bond Defects under Different Confining Conditions
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作者 Shuisheng Yu Jin Chen +2 位作者 Yawei Wang Honghao Yang Shucan Lu 《Journal of Modern Physics》 CAS 2023年第5期722-740,共19页
A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Theref... A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Therefore, in this study, confining pressure and pull-out load are applied to grouted rockbolt systems with bond defects by a numerical simulation method, and the rockbolt is detected by ultrasonic guided waves to study the propagation law of ultrasonic guided waves in defective rockbolt systems and the bond quality of rockbolts under the combined action of pull-out load and confining pressure. The numerical simulation results show that the length and location of bond defects can be detected by ultrasonic guided waves under the combined action of pull-out load and confining pressure. Under no pull-out load, with increasing confining pressure, the low-frequency part of the guided wave frequency in the rockbolt increases, the high-frequency part decreases, the weakening effect of the confining pressure on the guided wave propagation law increases, and the bond quality of the rockbolt increases. The existence of defects cannot change the strengthening effect of the confining pressure on the guided wave propagation law under the same pull-out load or the weakening effect of the pull-out load on the guided wave propagation law under the same confining pressure. 展开更多
关键词 Grouted Rockbolt systems Bond Defect Pull-Out Load Confining Pressure Ultrasonic Guided Wave
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