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Implications of small-bowel transit time in the detection rate of capsule endoscopy: A multivariable multicenter study of patients with obscure gastrointestinal bleeding 被引量:10
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作者 Carlo Maria Girelli Marco Soncini Emanuele Rondonotti 《World Journal of Gastroenterology》 SCIE CAS 2017年第4期697-702,共6页
AIMTo define the role of small-bowel transit time in the detection rate of significant small-bowel lesions.METHODSSmall-bowel capsule endoscopy records, prospectively collected from 30 participating centers in the Lom... AIMTo define the role of small-bowel transit time in the detection rate of significant small-bowel lesions.METHODSSmall-bowel capsule endoscopy records, prospectively collected from 30 participating centers in the Lombardy Registry from October 2011 to December 2013, were included in the study if the clinical indication was obscure gastrointestinal bleeding and the capsule reached the cecum. Based on capsule findings, we created two groups: P2 (significant findings) and P0-1 (normal/negligible findings). Groups were compared for age, gender, small-bowel transit time, type of instrument, modality of capsule performance (outpatients vs inpatients), bowel cleanliness, and center volume.RESULTSWe retrieved and scrutinized 1,433 out of 2,295 capsule endoscopy records (62.4%) fulfilling the inclusion criteria. Patients were 67 &#x000b1; 15 years old, and 815 (57%) were males. In comparison with patients in the P0-1 group, those in the P2 group (n = 776, 54%) were older (P &#x0003c; 0.0001), had a longer small-bowel transit time (P = 0.0015), and were more frequently examined in low-volume centers (P &#x0003c; 0.001). Age and small-bowel transit time were correlated (P &#x0003c; 0.001), with age as the sole independent predictor on multivariable analysis. Findings of the P2 group were artero-venous malformations (54.5%), inflammatory (23.6%) and protruding (10.4%) lesions, and luminal blood (11.5%).CONCLUSIONIn this selected, prospectively collected cohort of small-bowel capsule endoscopy performed for obscure gastrointestinal bleeding, a longer small-bowel transit time was associated with a higher detection rate of significant lesions, along with age and a low center volume, with age serving as an independent predictor. 展开更多
关键词 Capsule endoscopy Small-bowel transit time Detection rate Diagnostic yield Small bowel Obscure gastrointestinal bleeding PROKinETICS Suspect small-bowel bleeding
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Prediction of face advance rate and determination of the operation efficiency in retreat longwall mining panel using rock engineering system 被引量:6
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作者 Sajjad Aghababaei Hossein Jalalifar Gholamreza Saeedi 《International Journal of Coal Science & Technology》 EI 2019年第3期419-429,共11页
A new approach for prediction of face advance rete (FAR) prior to mining operation and determination of the operation efficiency after mining operation in retreat longwall mining panel is presented based upon the conc... A new approach for prediction of face advance rete (FAR) prior to mining operation and determination of the operation efficiency after mining operation in retreat longwall mining panel is presented based upon the concepts of rock engineering system (RES). For this purpose, six longwall panels considered in Parvadeh-I coal mine. Seven major effective parameters on FAR was selected including coal mine roof rating, gas propagation, safety factor of longwall face, ratio of joint spacing to cutting depth at longwall face, longwall face inclination, panel width, floor rock mass rating. To performance evaluation of the presented model, the relationship between the average vulnerability indexes of advance operation with FAR was determined in considered panels with coefficient of determination (R2) equal to 0.884 that indicate relatively acceptable correlation and compatibility. Investigations of the research indicated that it is possible to determine the actual operation efficiency under fair conditions by a RES-based model. The inevitable reduction of FAR for each longwall panel was determined by presented model that the difference amount between the maximum possible practical face advance rate (FARmpp) and recorded actual face advance rate (FARa) indicate the operation efficiency. Applied approach in this paper can be used to prediction of FAR in retreat longwall mining panel for same conditions that can have many benefits, including better and more accurate planning for the sales market and mine operation. Also, presented method in this paper can be applied as a useful tool to determination of actual operation efficiency for other sections and extraction methods in coal mines. 展开更多
关键词 FACE ADVANCE rate Rock engineering systems operation efficiency LONGWALL mining Parvadeh-I coal mine
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Dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates 被引量:1
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作者 Yuncheng Liu Ke Xu +4 位作者 Xuhao Fan Xinger Wang Xuan Yu Wei Xiong Hui Gao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期36-46,共11页
Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,... Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,highly smooth interactive holography remains a significant challenge due to the computational and display frame rate limitations.In this study,we introduced a dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates.To our knowledge,this is the first reported practical dynamic interactive metasurface holographic system.We spa-tially divided the metasurface device into multiple distinct channels,each projecting a reconstructed sub-pattern.The switching states of these channels were mapped to bitwise operations on a set of bit values,which avoids complex holo-gram computations,enabling an ultra-high computational frame rate.Our approach achieves a computational frame rate of 800 kHz and a display frame rate of 23 kHz on a low-power Raspberry Pi computational platform.According to this methodology,we demonstrated an interactive dynamic holographic Tetris game system that allows interactive gameplay,color display,and on-the-fly hologram creation.Our technology presents an inspiration for advanced dynamic meta-holography,which is promising for a broad range of applications including advanced human-computer interaction,real-time 3D visualization,and next-generation virtual and augmented reality systems. 展开更多
关键词 interactive display meta-holography bitwise operation ultra-high frame rate
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Design of a high sensitivity and wide range angular rate sensor based on exceptional surface
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作者 丁鑫圣 刘文耀 +7 位作者 王师贤 陶煜 周彦汝 白禹 刘来 邢恩博 唐军 刘俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期277-286,共10页
It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low an... It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low angular rate.However,in fact,the exceptional point is easily disturbed by external environmental variables,which means that it depends on harsh experimental environment and strong control ability,so it is difficult to move towards practical application.Here,we propose a new angular rate sensor structure based on exceptional surface,which has the advantages of high sensitivity and high robustness.The system consists of two fiber-optic ring resonators and two optical loop mirrors,and one of the resonators contains a variable ratio coupler and a variable optical attenuator.We theoretically analyze the system response,and the effects of phase and coupling ratio on the system response.Finally,compared with the conventional resonant gyro,the sensitivity of this exceptional surface angular rate sensor can be improved by about 300 times at low speed.In addition,by changing the loss coefficient in the ring resonator,we can achieve a wide range of 600 rad/s.This scheme provides a new approach for the development of ultra-high sensitivity and wide range angular rate sensors in the future. 展开更多
关键词 exceptional surface exceptional points ring resonator angular rate sensing rotational direction recognition wide operating range
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Cyberattack Ramifications, The Hidden Cost of a Security Breach
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作者 Meysam Tahmasebi 《Journal of Information Security》 2024年第2期87-105,共19页
In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term ... In this in-depth exploration, I delve into the complex implications and costs of cybersecurity breaches. Venturing beyond just the immediate repercussions, the research unearths both the overt and concealed long-term consequences that businesses encounter. This study integrates findings from various research, including quantitative reports, drawing upon real-world incidents faced by both small and large enterprises. This investigation emphasizes the profound intangible costs, such as trade name devaluation and potential damage to brand reputation, which can persist long after the breach. By collating insights from industry experts and a myriad of research, the study provides a comprehensive perspective on the profound, multi-dimensional impacts of cybersecurity incidents. The overarching aim is to underscore the often-underestimated scope and depth of these breaches, emphasizing the entire timeline post-incident and the urgent need for fortified preventative and reactive measures in the digital domain. 展开更多
关键词 Artificial intelligence (AI) Business Continuity Case Studies Copyright Cost-Benefit Analysis Credit Rating Cyberwarfare Cybersecurity Breaches Data Breaches Denial of Service (DOS) Devaluation of Trade Name Disaster Recovery Distributed Denial of Service (DDOS) Identity theft increased Cost to Raise Debt insurance Premium intellectual Property operational Disruption Patent Post-Breach Customer Protection Recovery Point Objective (RPO) Recovery Time Objective (RTO) Regulatory Compliance Risk Assessment Service Level Agreement Stuxnet Trade Secret
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Acute upper gastrointestinal bleeding in operated stomach: Outcome of 105 cases 被引量:9
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作者 Vassiliki N Nikolopoulou Konstantinos C Thomopoulos +2 位作者 George I Theocharis Vassiliki A Arvaniti Constantine E Vagianos 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第29期4570-4573,共4页
AIM: To compare the causes and clinical outcome of patients with acute upper gastrointestinal bleeding (AUGB) and a history of gastric surgery to those with AUGB but without a history of gastric surgery in the past.ME... AIM: To compare the causes and clinical outcome of patients with acute upper gastrointestinal bleeding (AUGB) and a history of gastric surgery to those with AUGB but without a history of gastric surgery in the past.METHODS: The causes and clinical outcome were compared between 105 patients with AUGB and a history of gastric surgery, and 608 patients with AUGB but without a history of gastric surgery.RESULTS: Patients who underwent gastric surgery in the past were older (mean age: 68.1±11.7 years vs 62.8±17.8 years, P= 0.001), and the most common cause of bleeding was marginal ulcer in 63 patients (60%). No identifiable source of bleeding could be found in 22 patients (20.9%) compared to 42/608 (6.9%) in patients without a history of gastric surgery (P = 0.003). Endoscopic hemostasis was permanently successful in 26 out of 35 patients (74.3%) with peptic ulcers and active bleeding or non-bleeding visible vessel. Nine patients (8.6%) were operated due to continuing or recurrent bleeding,compared to 23/608 (3.8%) in the group of patients without gastric surgery in the past (P= 0.028). Especially in peptic ulcer bleeding patients, emergency surgery was more common in the group of patients with gastric surgery in the past [9/73 (12.3%) vs 19/360 (5.3%), P = 0.025].Moreover surgically treated patients in the past required more blood transfusion (3.3±4.0 vs 1.5±1.7, P = 0.0001) and longer hospitalization time (8.6±4.0 vs 6.9±4.9 d,P = 0.001) than patients without a history of gastric surgery. Mortality was not different between the two groups [4/105 (3.8%) vs 19/608 (3.1%)].CONCLUSION: Upper gastrointestinal bleeding seems to be more severe in surgically treated patients than in non-operated patients. 展开更多
关键词 Operated stomach Active bleeding Endoscopic hemostasis
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Analysis of the Influence of Operating Room Nursing Care Management on the Incidence Rate of Nosocomial Infection in Orthopedic Surgery Patients 被引量:5
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作者 Lili Tan 《Journal of Clinical and Nursing Research》 2019年第2期7-10,共4页
Objective:To analysis the influence of operating room nursing care management on the incidence rate of nosocomial infection in orthopedic surgery patients.Methodology:Fifty six orthopedic surgery patients who admitted... Objective:To analysis the influence of operating room nursing care management on the incidence rate of nosocomial infection in orthopedic surgery patients.Methodology:Fifty six orthopedic surgery patients who admitted into the hospital between January to December 2018 were enrolled into this study and randomly divided into two groups,which were the control group(under general management)and the observation group(under the operating room nursing care management).Further,the incidence rate of nosocomial infections,the incidence rate of irregular nursing care phenomena,the satisfaction score of nursing care management,and the quality of life score were observed and recorded.Result:The incidence rate of nosocomial infection,the incidence rate of irregular nursing care management,the satisfaction score of nursing care management,and the quality of life score of the observation group were compared to that of the control group,and the result showed P<0.05,indicates the statistical significance between the data indicators.Conclusion:The use of operating room nursing care management in patients with orthopedic surgery has shown a significant effect. 展开更多
关键词 operating ROOM NURSinG CARE management ORTHOPEDIC surgery inCIDENCE rate of NOSOCOMIAL infection
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On the rate of convergence of two generalized Bernstein type operators 被引量:1
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作者 LIAN Bo-yong CAI Qing-bo 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第3期321-331,共11页
In this paper,we introduce the Bézier variant of two new families of generalized Bernstein type operators.We establish a direct approximation by means of the Ditzian-Totik modulus of smoothness and a global appro... In this paper,we introduce the Bézier variant of two new families of generalized Bernstein type operators.We establish a direct approximation by means of the Ditzian-Totik modulus of smoothness and a global approximation theorem in terms of second order modulus of continuity.By means of construction of suitable functions and the method of Bojanic and Cheng,we give the rate of convergence for absolutely continuous functions having a derivative equivalent to a bounded variation function. 展开更多
关键词 Bernstein operators modulus of smoothness rate of convergence bounded variation
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ON THE RATE OF POINTWISE CONVERGENCE OF THE DURRMEYER-TYPE OPERATORS 被引量:1
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作者 G. Aniol P. Pych-Taberska 《Analysis in Theory and Applications》 1995年第2期94-105,共12页
For bounded or some locally bounded functions f measurable on an interval I there is estimated the rate of convergence of the Durrmeyer-type operators Lnf at those points x∈IntI at which the one-sided limits f(x±... For bounded or some locally bounded functions f measurable on an interval I there is estimated the rate of convergence of the Durrmeyer-type operators Lnf at those points x∈IntI at which the one-sided limits f(x± 0) exist. In the main theorems the Chanturiya's modulus of variation is used. 展开更多
关键词 ON the rate of POinTWISE CONVERGENCE of the DURRMEYER-TYPE OPERATORS LIM
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Discussion on the Operation of Urban Domestic Sewage Treatment Facilities: A Case Study of Guangdong Province
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作者 Du Shuntao Yang Shewei +1 位作者 Guo Qian Huang Zhihua 《Meteorological and Environmental Research》 CAS 2019年第4期110-113,117,共5页
Urban sewage treatment facility is an important ways to control polluted domestic water. The operation of urban sewage treatment facilities is good or not, and whether the effectiveness of pollutant emission reduction... Urban sewage treatment facility is an important ways to control polluted domestic water. The operation of urban sewage treatment facilities is good or not, and whether the effectiveness of pollutant emission reduction can be exerted play a significant role in reducing the pollution of living sources. Nowadays the operation of urban sewage treatment facilities is mainly evaluated by the load rate. However, due to the failure to fully implement the reformation of the rainwater and polluted water in Guangdong Province, the domestic sewage is mixed with rainwater during the rainy season and is included in the treatment of urban sewage treatment facilities. Therefore, it is not objective to evaluate the operation of sewage treatment facilities using only the load rate of sewage treatment. According to the situation of Guangdong Province, the load rates of COD, ammonia nitrogen and total phosphorus in domestic sewage and load rate of sewage treatment were included in the evaluation, and 20 urban sewage treatment facilities were selected as research objects. The operation situations and emission reduction benefits of urban sewage treatment facilities in different regions of Guangdong Province were roughly evaluated. 展开更多
关键词 operation evaluation URBAN SEWAGE TREATMENT facilities LOAD rate of SEWAGE TREATMENT LOAD rate of COD LOAD rate of AMMONIA nitrogen LOAD rate of total phosphorus
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Effects of Anthropometry Variations on Physiological Parameters of Heart Rate, Oxygen Consumption, Aerobic Power While Performing Manual Operation at Fixed Vice Height
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作者 Olusegun Gideon Akanbi Bukola Olanrewaju Afolabi Omowumi Adegboye 《Engineering(科研)》 2020年第1期47-57,共11页
This study investigated the effect of fixed height standing-workstation on different people with diverse anthropometry dimensions. Measurements of some anthropometric and physiological parameters are carried out as ba... This study investigated the effect of fixed height standing-workstation on different people with diverse anthropometry dimensions. Measurements of some anthropometric and physiological parameters are carried out as bases for the calculation of body mass index (BMI) and the determination of the maximum heart rate (HRmax) and aerobic power (VO2max) of individual subject while performing manual cutting operation with hacksaw on fixed vice height of 940 mm. Twenty subjects (S1 to S20) parted 2 mm thick square-pipe of 25 mm × 25 mm. Each subject carried out cutting operation in 5 replicates and their physiological parameters during activities are measured to determine their expended energy (EE) and oxygen consumption rate (VO2). The results showed that subject S4 with BMI of 20.76 kg/m2 has maximum cutting rate of 5.33 stroke/s, while subject S8 with BMI of 23.39 kg/m2 has minimum cutting rate of 0.92 stroke/s. There was a statistically significant effect on the interaction between BMI, EE and Cutting rate, with F = 827.54, P = 0.000, R2 = 0.967 and S = 1.749 units. Subject S11 was discovered to have VO2 (28.54 l/min) and VO2max (24.36 ml/min/kg), with highest value of EE (2.94 kcal/min). Wear rates of 1.86 teeth/s and 9.55 teeth/s have the same energy cost (EE = 0.87 kcal/min) but different cutting time of 36.65 s (S18) and 10.89 s (S20) respectively. This could explain in-part that excess 25.76 s utilized in operation time by subject S18 is responsible for keeping approximately 7.7 teeth intact as regards tool management. EE and Tool Wear Rate in one-way analysis of variance, were statistically significant (F = 45.87, P = 0.000, R2 = 54.69% and S = 1.617 units) at 0.05 level. 展开更多
关键词 ANTHROPOMETRY Variation Cutting operation Fixed VICE HEIGHT PHYSIOLOGICAL Parameters Wear rate
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REGULARIZATION METHOD FOR IMPROVING OPTIMAL CONVERGENCE RATE OF THE REGULARIZED SOLUTION OF ILL-POSED PROBLEMS 被引量:4
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作者 侯宗义 杨宏奇 《Acta Mathematica Scientia》 SCIE CSCD 1998年第2期177-185,共9页
This paper presents anew regularization method for solving operator equations of the first kind; the convergence rate of the regularized solution is improved, as compared with the ordinary Tikhonov regularization.
关键词 operator equation of the first kind regularization method CONVERGENCE convergence rate of the regularized solution
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The Relationship between the Performance of Listed Companies in Pharmaceutical Manufacturing and Inventory Turnover, Operating Rate
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作者 Yutong Hai 《经济管理学刊(中英文版)》 2019年第1期9-21,共13页
As an important part of the pharmaceutical industry, the pharmaceutical manufacturing industry is always at the battlefield of the international public health and health industry. At the same time, as a basic and stra... As an important part of the pharmaceutical industry, the pharmaceutical manufacturing industry is always at the battlefield of the international public health and health industry. At the same time, as a basic and strategic sub-industry in China's manufacturing industry, the medical manufacturing industry closely related to people’s livelihood which is not only related to social Responsibility but also plays a key role in China's economy today. For the Chinese people, the new medical reforms and the irreversible aging of the population have increased the nation’s total expenditure on health care. From January to October 2017, the pharmaceutical industry’s main business income was RMB 2,410.29 billion, a year-on-year increase of 13.10%. This is a 4.50 percentage point higher than the 10.30% growth rate in 2016. However, even if the circumstance of this industry is getting better, high growth also has a drag on the national health insurance system and the standard of living of the people. This article chooses to analyze the financial and operating-level factors of China's pharmaceutical manufacturing listed companies such as Inventory turnover rate and operating rate. Study the impact on the performance of China's pharmaceutical manufacturing listed companies. The results of the study will fill gaps in the research of this industry and help pharmaceutical manufacturing listed companies choose the right capital size, liabilities, and expansion strategies, and more effectively absorb the current development dividends of China’s “four new economy”, and use them rationally and effectively. Markets and complex and limited capital and resources of enterprises, as China's industry benchmarks continue to guide the rapid growth of the market. on the other hand, to help investor the empirical point of view better choice of investment targets. This paper uses data from 2007-2016 for randomly selecting 19 companies from 118 medical manufacturing listed companies classified by China Securities Regulatory Commission. After dealing with panel data, multiple inspections are performed on panel data. To avoid the deviation from the actual level of the regression results, the panel-corrected standard deviation model was used to derive the relationship between the operating-level factors of pharmaceutical manufacturing listed companies and their performance. The results of the study indicate that there is a positive correlation between Inventory turnover rate, operating rate and performance, which fills the domestic empirical research on this issue. This area of industry company performance is blank. 展开更多
关键词 PHARMACEUTICAL Manufacturing LISTED Companies CORPORATION PERFORMANCE Panel Data inventory TURNOVER Operating rate of Return
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Clinical observation of Furongtongmai capsule on the lower extremity Atherosclerotic Occlusive Disease after Intervention Operation
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作者 Wei Yao Xiu-Hai Su +7 位作者 Yuan-Song Wang Yan-Ling Du Zhan-Yi Gao Yin-Sheng Gao Na Li Na-Na Feng Qing Chen Hua Guo 《TMR Modern Herbal Medicine》 2018年第4期203-208,共6页
Objective To investigate the effect of Furongtongmai capsule on the in-stent restenosis (ISR) of superficial femoral artery after interventional operation in lower extremity Arteriosclerosis Occlusion (ASO).... Objective To investigate the effect of Furongtongmai capsule on the in-stent restenosis (ISR) of superficial femoral artery after interventional operation in lower extremity Arteriosclerosis Occlusion (ASO). Methods: A total of 110 inpatients with ASO who performed Superficial femoral artery stent implantation were randomly divided into observation group and control group, with 55 cases in each group.Both groups received Aspirin 100 mg/d and Clopidogrel 75 mg/d. The observation group was given Furongtongmai capsule on the basis of routine treatment. After continuous treatment for 6 months, the clinical efficacy, Ankle Brachial Index (ABI), high-sensitivity C-reactive protein (Hs-CPR) and ISR were compared between the two groups. Results: At 6 months after operation, the plasma levels of Hs-CRP in the two groups were significantly lower than those in the control group (P 〈 0.05). The ABI of treatment group was significantly higher than the control group (P 〈 0.05). There was a statistically significant difference in ISR incidence between the treatment group and the control group 6 months after surgery (9.09% vs 27.78%, P 〈 0.05). Conclusion: Furongtongmai Capsule can inhibit Hs-CRP in patients with ASO after femoral artery intervention, improve the ankle brachial index and reduce the incidence of ISR. 展开更多
关键词 Furongtongmai capsule Lower extremity atherosclerotic occlusive disease intervention operation restenosis rate HS-CRP
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NUMERICAL RESEARCH ON IMPACT OF AIR SYSTEM BLEEDING ON COMPRESSOR PERFORMANCE 被引量:1
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作者 赵斌 李绍斌 +1 位作者 李秋实 周盛 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第1期38-47,共10页
Bled air from the high pressure compressor takes up 3%—5% in the air system.However,there are not many studies on the compressor performance after bleeding.By analyzing the low-speed single-stage compressors,six blee... Bled air from the high pressure compressor takes up 3%—5% in the air system.However,there are not many studies on the compressor performance after bleeding.By analyzing the low-speed single-stage compressors,six bleeding structures are presented according to their influence mechanism on the compressor performance,and five kinds of bleeding rate are applied to one of the structures.A numerical simulation is performed to study the influence of bleeding rates and structures on the compressor performance.The results show that for the stators with the large flow separation in the corner,bleeding a small amount of air from the end-wall region can improve the total pressure increase and the stability margin.Moreover there is an optimum value of the bleeding rate in the stator casing. 展开更多
关键词 compressors bleeding air system bleeding structure bleeding rate
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Application of subsurface wastewater infiltration system to on-site treatment of domestic sewage under high hydraulic loading rate 被引量:7
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作者 Ying-hua Li Hai-bo Li +2 位作者 Xin-yang Xu Xuan Gong Yong-chun Zhou 《Water Science and Engineering》 EI CAS CSCD 2015年第1期49-54,共6页
In order to enhance the hydraulic loading rate (HLR) of a subsurface wastewater infiltration system (SWIS) used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results sh... In order to enhance the hydraulic loading rate (HLR) of a subsurface wastewater infiltration system (SWIS) used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio (RwD) was 1.0, the pollutant removal rate increased by (13.6 ± 0.3)% for NH3-N, (20.7 ± 1.1)% for TN, (18.6± 0.4)% for TP, (12.2 ± 0.5)% for BOD, (10.1 ± 0.3)% for COD, and (36.2 ± 1.2)% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water - Water Quality Standard for Scenic Environment Use (GB/T 18921-2002) even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential (ORP), the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the RWD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference (p 〈 0.05) under different RwDS. The suggested RWD was 1.0. Relative contribution of the pretreatment and SWlS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS. 展开更多
关键词 Domestic sewage Subsurface wastewater infiltration system intermittent operation mode Hydraulic loading rate Pollutant removal rate
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Serum gastrin-17 concentration for prediction of upper gastrointestinal tract bleeding risk among peptic ulcer patients 被引量:10
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作者 Jun-Xian Wang Yu-Ping Cao +3 位作者 Peng Su Wei He Xiao-Ping Li Ya-Meng Zhu 《World Journal of Clinical Cases》 SCIE 2021年第35期10948-10955,共8页
BACKGROUND Serum gastrin-17(G-17),pepsinogen I(PGI),and pepsinogen II(PGII)concentrations regulate gastric acid secretion,and hypersecretion of gastric acid increases the risks of peptic ulcer and upper gastrointestin... BACKGROUND Serum gastrin-17(G-17),pepsinogen I(PGI),and pepsinogen II(PGII)concentrations regulate gastric acid secretion,and hypersecretion of gastric acid increases the risks of peptic ulcer and upper gastrointestinal bleeding.These associations suggest that serum G-17,PGI,and(or)PGII may predict gastrointestinal bleeding risk among peptic ulcer patients.AIM To evaluate the efficacies of serum G-17,PGI,PGII,and PGI/PGII ratio(PGR)for predicting upper gastrointestinal bleeding among peptic ulcer patients.METHODS A total of 199 patients diagnosed with peptic ulcer confirmed by gastroscopy and positivity for Helicobacter pylori by the 14C-urea breath test were recruited,including 107 patients with simple peptic ulcer and 92 cases complicated by upper gastrointestinal bleeding.Serum PGI,PGII,G-17,and PGR were measured by immune methods and compared between bleeding and non-bleeding groups by univariate analysis.The specificity and sensitivity of PGs and G-17 for evaluating upper gastrointestinal bleeding risk were then assessed by constructing receiver operating characteristic(ROC)curves.RESULTS Serum G-17 was significantly higher among peptic ulcer patients with upper gastrointestinal bleeding compared to simple peptic ulcer patients(25.34±14.29 vs 8.84±8.03 pmol/L,t=9.822,P<0.01),whereas serum PGI,PGII,and PGR did not differ significantly between bleeding and non-bleeding groups(all P>0.05).The risk of bleeding was significantly higher among peptic ulcer patients with elevated serum G-17(>15 pmol/L)compared to patients with normal or low serum G-17(73.2%vs 27.4%,χ2=40.72,P<0.01).The area under the ROC curve for serum G-17 was 0.866±0.024,and a cut-off of 9.86 pmol/L yielded 90.2%sensitivity and 68.2%specificity for distinguishing peptic ulcer with and without upper gastrointestinal bleeding.CONCLUSION Serum G-17 is significantly upregulated in peptic ulcer patients and higher levels are predictive of upper gastrointestinal bleeding.Conversely,serum PGI,PGII,and PGR have no predictive value.Further prospective studies are warranted to examine if high G-17 can be used to assess risk of bleeding prior to onset. 展开更多
关键词 Peptic ulcer Upper gastrointestinal bleeding GASTRin PEPSinOGEN Receiver operating characteristic curve
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A quantitative model for danger degree evaluation of staged operation of earth dam reservoir in flood season and its application 被引量:3
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作者 Chong-xun Mo Gui-yan Mo +3 位作者 Qing Yang Yu-li Ruan Qing-ling Jiang Ju-liang Jin 《Water Science and Engineering》 EI CAS CSCD 2018年第1期81-87,共7页
Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for ... Based on the natural disaster risk evaluation mode, a quantitative danger degree evaluation model was developed to evaluate the danger degree of earth dam reservoir staged operation in the flood season. A formula for the overtopping risk rate of the earth dam reservoir staged operation was established, with consideration of the joint effect of flood and wind waves in the flood sub-seasons with the Monte Carlo method, and the integrated overtopping risk rate for the whole flood season was obtained via the total probability approach. A composite normalized function was used to transform the dam overtopping risk rate into the danger degree, on a scale of 0-1. Danger degree gradating criteria were divided by four significant characteristic values of the dam overtopping rate, and corresponding guidelines for danger evaluation are explained in detail in this paper. Examples indicated that the dam overtopping danger degree of the Chengbihe Reservoir in China was 0.33-0.57, within the range of moderate danger level, and the flood-limiting water level (FLWL) can be adjusted to 185.00 m for the early and main flood seasons, and 185.00-187.50 m for the late flood season. The proposed quantitative model offers a theoretical basis for determination of the value of the danger degree of an earth dam reservoir under normal operation as well as the optimal scheduling scheme for the reservoir in each stage of the flood season. 展开更多
关键词 Reservoir staged operation in flood season Earth dam Danger degree Quantitative evaluation Overtopping risk rate
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Optimal Operation with Dynamic Partitioning Strategy for Centralized Shared Energy Storage Station with Integration of Large-scale Renewable Energy 被引量:1
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作者 Jianlin Li Zhijin Fang +3 位作者 Qian Wang Mengyuan Zhang Yaxin Li Weijun Zhang 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2024年第2期359-370,共12页
As renewable energy continues to be integrated into the grid,energy storage has become a vital technique supporting power system development.To effectively promote the efficiency and economics of energy storage,centra... As renewable energy continues to be integrated into the grid,energy storage has become a vital technique supporting power system development.To effectively promote the efficiency and economics of energy storage,centralized shared energy storage(SES)station with multiple energy storage batteries is developed to enable energy trading among a group of entities.In this paper,we propose the optimal operation with dynamic partitioning strategy for the centralized SES station,considering the day-ahead demands of large-scale renewable energy power plants.We implement a multi-entity cooperative optimization operation model based on Nash bargaining theory.This model is decomposed into two subproblems:the operation profit maximization problem with energy trading and the leasing payment bargaining problem.The distributed alternating direction multiplier method(ADMM)is employed to address the subproblems separately.Simulations reveal that the optimal operation with a dynamic partitioning strategy improves the tracking of planned output of renewable energy entities,enhances the actual utilization rate of energy storage,and increases the profits of each participating entity.The results confirm the practicality and effectiveness of the strategy. 展开更多
关键词 Shared energy storage(SES) dynamic partitioning strategy optimal operation Nash bargaining theory actual utilization rate of energy storage
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Dynamic behavior of a rotating gliding arc plasma in nitrogen:effects of gas flow rate and operating current 被引量:1
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作者 张浩 朱凤森 +1 位作者 李晓东 杜长明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第4期42-47,共6页
The effects of feed gas flow rate and operating current on the electrical characteristics and dynamic behavior of a rotating gliding arc (RGA) plasma codriven by a magnetic field and tangential flow were investigate... The effects of feed gas flow rate and operating current on the electrical characteristics and dynamic behavior of a rotating gliding arc (RGA) plasma codriven by a magnetic field and tangential flow were investigated.The operating current has been shown to significantly affect the time-resolved voltage waveforms of the discharge,particularly at flow rate =21 min^-1.When the current was lower than 140 mA,sinusoidal waveforms with regular variation periods of 13.5-17.0 ms can be observed (flow rate =21 min^-1).The restrike mode characterized by serial sudden drops of voltage appeared under all studied conditions.Increasing the flow rate from 8 to 121 min^-1 (at the same current) led to a shift of arc rotation mode which would then result in a significant drop of discharge voltage (around 120-200 V).For a given flow rate,the reduction of current resulted in a nearly linear increase of voltage. 展开更多
关键词 rotating gliding arc (RGA) electrical characteristics gas flow rate operating current rotation mode
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