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The Impact and Intervention of Handheld Tai Chi Water-Resistance Fitness Ball on Middle-Aged and Elderly Patients with Parkinson’s Disease
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作者 He Huang 《Health》 2024年第4期319-349,共31页
Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionna... Through the use of a survey and statistical methods, this study explores the effects and interventions of handheld Tai Chi water resistance fitness balls on the elderly with Parkinson’s disease. Firstly, a questionnaire on exercise compliance for patients with Parkinson’s disease was developed, and its reliability and validity were tested. Then, a survey was conducted to investigate the current status of exercise compliance among Parkinson’s disease patients, including general information, scoring status, and single and multiple factor analyses of influencing factors [1]. The results of the study show that through qualitative research, the dimensions and item pools of the questionnaire were initially constructed, and the reliability analysis of the questionnaire was conducted through Delphi expert consultation, with favorable results in terms of its reliability and validity [2]. Regarding the current status of exercise compliance among Parkinson’s disease patients, the study found that the level of exercise compliance needs improvement, and there are significant differences in exercise compliance levels among patients under different circumstances. Finally, the research results were discussed and conclusions were drawn. The innovation of this study lies in the development of a questionnaire on exercise compliance for patients with Parkinson’s disease and the preliminary qualitative research and Delphi expert consultation conducted on it, providing new ideas and methods for the study of exercise compliance. However, the study also has limitations as it did not examine the effects of other interventions on Parkinson’s disease, so further research should be conducted [3]. 展开更多
关键词 Parkinson’s Disease Exercise Compliance Tai Chi Water resistance Fitness Ball Influencing Factors Intervention effectiveness
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The Effect of Respiratory Care on the Treatment of Asthma Patients
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作者 Yuling Hua 《Journal of Clinical and Nursing Research》 2024年第1期13-18,共6页
Objective:To analyze the intervention effect of respiratory care on asthma patients.Methods:49 asthma patients admitted to the hospital between December 1,2018 and November 30,2022 were selected for this study.The pat... Objective:To analyze the intervention effect of respiratory care on asthma patients.Methods:49 asthma patients admitted to the hospital between December 1,2018 and November 30,2022 were selected for this study.The patients were divided into Group A(25 cases)and Group B(24 cases).The patients in Group A received respiratory care,while the patients in Group B received routine care,and the nursing effects of both groups were compared.Results:Group A demonstrated a better nursing effect compared to Group B;the patients in Group A were generally more satisfied with the care given compared to those of Group B.Furthermore,Group A showed better improvements in respiratory function compared to Group B(P<0.05).Before care,there was no difference in quality-of-life scores between the two groups(P>0.05).After care,Group A’s quality of life score was lower than Group B’s(P<0.05).Conclusion:Respiratory care for asthma patients can improve the quality of care and patient satisfaction.Besides,it also leads to a better improvement in respiratory function and the quality of life of the patients. 展开更多
关键词 respiratory care ASTHMA Nursing effect respiratory function Quality of life
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Effect of different cold air intensities and their lagged effects on outpatient visits for respiratory illnesses in Handan in different seasons
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作者 Xingshan Zhang Guiqin Fu +4 位作者 Liang Zhao Ji Wang Caimeng Liang Juanhuai Wang Meng Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期39-44,共6页
本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分... 本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分别在冷空气日后两天和五天增加18.4%和13.3%,而冬季就诊人数在冷空气日后三天仅增加3.2%.冷空气对疾病影响的滞后时间在夏,秋和冬季随冷空气强度的增加而减少,而春季的滞后时间总是很长.这些发现可为科学应对气候异常导致的人群健康风险提供针对性依据. 展开更多
关键词 冷空气过程 降温幅度 呼吸系统疾病 滞后效应
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Observation on the Effect of Non-Invasive Ventilator Combined with Conventional Therapy in the Treatment of Chronic Obstructive Pulmonary Disease Complicated with Respiratory Failure
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作者 Cheng Shi 《Journal of Clinical and Nursing Research》 2024年第2期104-110,共7页
Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.M... Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:68 patients with COPD combined with respiratory failure treated in our hospital from September 2021 to October 2023 were selected as the research subjects.Using the random number table method,they were divided into a control group and an experimental group of 34 cases each.The control group received conventional symptomatic treatment,and the experimental group received non-invasive ventilator treatment based on the control group.The clinical effects,blood gas indicators(partial pressure of carbon dioxide(PaCO_(2)),partial pressure of oxygen(PaO_(2)),arterial oxygen saturation(SaO_(2))),lung function(forced expiratory volume in 1 second(FEV1),forced vital capacity(FVC),6 min walking distance),complications,and inflammatory factor levels(c-reactive protein(CRP),interleukin-6(IL-6),neutrophil-to-lymphocyte ratio(NLR))of the two groups of patients were observed.Results:(1)The clinical efficacy of the patients in the experimental group(33/97.06%)was more significant as compared with the control group(25/73.53%)(P<0.05);(2)After treatment,the clinical efficacy of the two groups of patients in terms of FEV1,FEV1/FVC,6-minute walking distance,PaO_(2)and SaO_(2)all increased in the experimental group as compared to that of the control group(P<0.05);(3)After treatment,the PaCO_(2),CRP,IL-6,and NLR of the two groups of patients decreased,and the decrease in the experimental group was higher than that of the control group(P<0.05);(4)The patients’complication rate in the experimental group(2/5.88%)was lower as compared to that of the control group(9/26.46%)(P<0.05).Conclusion:Non-invasive ventilators combined with conventional therapy achieved good clinical results in treating patients with COPD and respiratory failure. 展开更多
关键词 Non-invasive ventilator Conventional therapy Chronic obstructive pulmonary disease respiratory failure Clinical effect
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The action mechanism of the work done by the electric field force on moving charges to stimulate the emergence of carrier generation/recombination in a PN junction
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作者 Lingyun GUO Yizhan YANG +1 位作者 Wanli YANG Yuantai HU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1001-1014,共14页
It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron curren... It is discovered that the product of the current and the electric field in a PN junction should be regarded as the rate of work(power)done by the electric field force on moving charges(hole current and electron current),which was previously misinterpreted as solely a Joule heating effect.We clarify that it is exactly the work done by the electric field force on the moving charges to stimulate the emergence of non-equilibrium carriers,which triggers the novel physical phenomena.As regards to Joule heat,we point out that it should be calculated from Ohm’s law,rather than simply from the product of the current and the electric field.Based on this understanding,we conduct thorough discussion on the role of the electric field force in the process of carrier recombination and carrier generation.The thermal effects of carrier recombination and carrier generation followed are incorporated into the thermal equation of energy.The present study shows that the exothermic effect of carrier recombination leads to a temperature rise at the PN interface,while the endothermic effect of carrier generation causes a temperature reduction at the interface.These two opposite effects cause opposite heat flow directions in the PN junction under forward and backward bias voltages,highlighting the significance of managing device heating phenomena in design considerations.Therefore,this study possesses referential significance for the design and tuning on the performance of piezotronic devices. 展开更多
关键词 piezoelectric semiconductor(PS) work done by electric field force thermal effect piezotronic device resistivity conductivity
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Respiratory Mechanics, Respiratory Muscle Strength, Control of Ventilation and Gas Exchange in Patients with Autoimmune Liver Disease
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作者 Ahmet Baydur Jacob Korula 《Open Journal of Respiratory Diseases》 2024年第2期25-38,共14页
Objectives: To assess respiratory elastance and resistive properties in patients with autoimmune liver disorders using the passive relaxation expiration technique and compare findings to a group of patients with non-a... Objectives: To assess respiratory elastance and resistive properties in patients with autoimmune liver disorders using the passive relaxation expiration technique and compare findings to a group of patients with non-autoimmune liver disease and control subjects. These findings were then related to control of ventilation and gas exchange. A secondary objective was to assess respiratory muscle strength and gas exchange and their relation to respiratory mechanics. Methods: Measurements included respiratory elastance and resistance using the passive relaxation method. Pulmonary function, gas exchange and control of ventilation were assessed using standard methods. Results: a) Compared to control subjects, Ers in patients with liver disease was on average 50% greater than in controls;b) mean respiratory resistance, expressed as the respiratory constants, K<sub>1</sub> and K<sub>2</sub> in the Rohrer relationship, Pao/V’ = K<sub>1</sub> + K<sub>2</sub>V’, was not different from control resistance;c) mean maximal inspiratory and maximal expiratory pressures averaged 36% and 55% of their respective control values;d) inspiratory occlusion pressure in 0.1 sec (P<sub>0.1</sub>) was increased and negatively associated with FVC;and e) increases in P<sub>0.1</sub>, mean inspiratory flow (Vt/Ti) and presence of respiratory alkalosis confirmed the increase in ventilatory drive. Despite inspiratory muscle weakness in patients, P<sub>0.1</sub>/Pimax averaged 5-fold higher than in control subjects. Conclusions: Despite inspiratory muscle weakness and a V’<sub>E</sub> similar to that in normal subjects, central drive is increased in patients with chronic liver disease. The increase in ventilatory drive is related to smaller lung volumes and weakly associated with increase in respiratory elastance. Findings confirm that P<sub>0.1</sub> is a reliable measure of central drive and is an approach that can be used in the evaluation of control of ventilation in patients with chronic liver disease. 展开更多
关键词 Autoimmune Liver Disease Control of Ventilation Occlusion Pressure Passive Relaxation Method Primary Biliary Cirrhosis respiratory Elastance respiratory resistance
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Clinical Study on Respiratory Medicine Treatment of Chronic Obstructive Pulmonary Disease Combined with Respiratory Failure
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作者 Jianhua Yu 《Journal of Clinical and Nursing Research》 2024年第5期293-298,共6页
Objective:To explore the respiratory medicine treatment methods for treating chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:70 cases of COPD patients with combined respiratory fai... Objective:To explore the respiratory medicine treatment methods for treating chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:70 cases of COPD patients with combined respiratory failure admitted to our hospital from January 2021 to January 2023 were selected as the study subjects,and randomly divided into the control group and the experimental group,each with 35 cases.The control group received only conventional treatment,and the experimental group received non-invasive positive pressure ventilation,and the treatment effects and changes in the levels of IL-18,hs-CRP,and CES2 inflammatory factors were observed and evaluated in the two groups.Results:There was no significant difference between the general data of the two groups(P>0.05);after treatment,the total effective rate of clinical efficacy of the observation group(91.43%)was significantly higher than that of the control group(71.43%),and the difference showed a significant correlation(P<0.05);after treatment,the level of inflammatory factor of the observation group was significantly reduced compared with that of the control group,and the difference showed a highly significant correlation(P<0.001).Conclusion:The non-invasive positive pressure ventilation treatment program significantly improves the therapeutic effect,effectively controls the level of inflammatory factors,and improves the health status of patients when dealing with patients with chronic obstructive pulmonary disease accompanied by respiratory failure,showing a good clinical application prospect. 展开更多
关键词 Chronic obstructive pulmonary disease respiratory failure Non-invasive positive pressure ventilation therapeutic effect Inflammatory factor
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Selection,effective dominance,and completeness of Cry1A.105/Cry2Ab2 dual-protein resistance in Helicoverpa zea(Boddie)(Lepidoptera:Noctuidae)
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作者 Tiago SILVA Ying NIU +4 位作者 Tyler TOWLES Sebe BROWN Graham PHEAD Wade WALKER Fangneng HUANG 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2151-2161,共11页
In the U.S.,Helicoverpa zea(Boddie)is a major pest targeted by both transgenic maize and cotton expressing Bacillus thuringiensis(Bt)proteins.Resistance of insect to Bt maize and cotton containing cry1A and cry2A gene... In the U.S.,Helicoverpa zea(Boddie)is a major pest targeted by both transgenic maize and cotton expressing Bacillus thuringiensis(Bt)proteins.Resistance of insect to Bt maize and cotton containing cry1A and cry2A genes has widely occurred in the U.S.In this study,two trials were performed to investigate larval survival and development of a Cry1A.105/Cry2Ab2 dual-protein resistant(VT2P-RR),a susceptible,and an F1 heterozygous(VT2P-RS)populations of H.zea on ears of nine Bt and three non-Bt maize hybrids.The Bt maize hybrids evaluated represent five common pyramided traits expressing two or three of the Cry1A.105,Cry1Ab,Cry1F,Cry2Ab2,and Vip3Aa20 proteins.In the laboratory,neonates of the three H.zea populations were inoculated on silks of ears collected from maize at R1-R2 plant stages;and larval survivorship was checked 10 d after neonate release.All three insect populations survived normally on non-Bt maize ears.Varied numbers of VT2P-RR and VT2P-RS survived on ears of Cry1A.105/Cry2Ab2 maize,while all larvae of the three populations died or could not develop on ears of Vip3Aa20-expressing maize.The results demonstrated that the dual-protein resistant H.zea was not cross-resistant to Vip3Aa20-expressing maize,and thus traits with vip3Aa20 gene should be effective to manage Cry1A.105/Cry2Ab2-resistant H.zea.The resistance in VT2P-RR was determined to be incomplete on Cry1A.105/Cry2Ab2 maize.The effective dominance levels varied greatly,from recessive to incompletely dominant,depending on maize hybrids and trials,suggesting that proper selection of maize hybrids could be important for mitigating the Cry1A.105/Cry2Ab2 resistance.The data generated should aid in modeling multiple-protein Bt resistance in H.zea. 展开更多
关键词 corn earworm Cry1A/Cry2A effective dominance incomplete resistance Bt maize resistance management
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Investigation on the Fire Resistance of Cellular Steel Beam with Sinusoidal Openings
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作者 Michee Sagali Mutentu Bikoumou Gambat Maximino Horacio Yinghua Yang 《Open Journal of Civil Engineering》 2023年第4期637-663,共27页
This paper investigated the fire resistance of CSBs with various parameters under high temperature rise due to fire using finite element software ABAQUS. The mechanical parameters of CSBs are analyzed, including load-... This paper investigated the fire resistance of CSBs with various parameters under high temperature rise due to fire using finite element software ABAQUS. The mechanical parameters of CSBs are analyzed, including load-bearing capacity and the temperature distribution during the heating process. Through structural analysis simulation of the entire heating process, the structural response of the CSBs is divided into five stages: elastic stage, elastic-plastic stage, self-balancing stage, catenary stage and ultimate destruction stage. The results indicate that the opening diameter-to-height ratio, opening spacing-to-height ratio and load ratio significantly affect the structural responses of CSBs in fire, followed by opening shape as secondary effects. In all the numerical analyzes, CSBs are analyzed with a uniformly distributed load and having simply supported boundary conditions. 展开更多
关键词 Fire resistance thermal and Structural Analysis Cellular Steel Beam Transient Temperature Effect
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Application of Flipped Classroom Combined with PBL Teaching Method in the Teaching of Respiratory Intensive Care Unit Nursing
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作者 Ying Li Xiaoling Bai Xiangli Zhang 《Journal of Contemporary Educational Research》 2023年第10期46-51,共6页
Objective:The aim is to investigate the application effect of flipped classroom combined with problem-based learning(PBL)teaching method in the teaching of respiratory intensive care unit nursing.Methods:100 fresh nur... Objective:The aim is to investigate the application effect of flipped classroom combined with problem-based learning(PBL)teaching method in the teaching of respiratory intensive care unit nursing.Methods:100 fresh nursing students who were interned in the respiratory intensive care unit of our hospital from June 2020 to May 2022 were selected and randomly divided into 50 students in the control group and 50 students in the experimental group.The students in the control group were taught by PBL teaching method,and the students in the experimental group were taught by flipped classroom combined with PBL teaching method.After the completion of the teaching,the teachers combined the performance of the two groups of students,and scored them comprehensively in terms of their professional theoretical knowledge,clinical operation skills,independent learning ability,and teamwork ability,and carried out a survey of the experimental group’s students in terms of their satisfaction with the understanding of theoretical knowledge,clinical operation,independent learning ability,teamwork ability,and other dimensions.Results:There was no statistical significance in the specialized theoretical knowledge scores of the two groups of students(P>0.05).The scores of clinical operation,independent learning ability,and teamwork ability of the two groups of students were statistically significant(P<0.05),and all the scores of the students in the experimental group were higher than that of the control group.More than 90%of the students believed that the flipped classroom combined with PBL teaching method could assist in the comprehension of theoretical knowledge,improve the clinical operation skills,enhance the ability of independent learning and teamwork;there were 92%of the students supported the use of flipped classroom combined with PBL teaching in respiratory intensive care unit nursing teaching.Conclusion:In the teaching of respiratory intensive care unit nursing,the use of flipped classroom combined with PBL teaching method can improve the learning effect of students,and has certain value in teaching. 展开更多
关键词 Flipped classroom PBL teaching method respiratory intensive care unit Nursing teaching Application effect Medical education
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Testing Low Doses of Caffeine on Respiratory Resistance Using the Airflow Perturbation Device 被引量:1
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作者 Mary Kate Montgomery Allen Luk +1 位作者 Arthur T. Johnson Jafar Vossoughi 《Open Journal of Respiratory Diseases》 2017年第2期53-61,共9页
Research reports on pulmonary function measurements often mention caffeine abstinence as a condition for testing subjects. Yet, the effects of caffeine on respiration are not well documented. This study was intended t... Research reports on pulmonary function measurements often mention caffeine abstinence as a condition for testing subjects. Yet, the effects of caffeine on respiration are not well documented. This study was intended to investigate the physiological effects of caffeine on respiratory resistance measurements and the necessity of caffeine avoidance in such testing. Thirty-one subjects were administered caffeine in pill form for dosages in the range of 3 - 4.5 mg/kg body weight. Respiratory resistance was measured with the Airflow Perturbation Device every 15 minutes after caffeine ingestion until a full hour of elapsed time. No changes were noted in inhalation, exhalation, and average respiratory resistances during the times of measurements. The conclusion is that for low dosages of caffeine, respiratory resistance measurements are not affected by caffeine ingestion prior to testing. 展开更多
关键词 respiratory resistance CAFFEINE
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Effect of Geometry of Filler Particles on the Effective Thermal Conductivity of Two-Phase Systems 被引量:1
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作者 Deepti Chauhan Nilima Singhvi Ramvir Singh 《International Journal of Modern Nonlinear Theory and Application》 2012年第2期40-46,共7页
The present paper deals with the effect of geometry of filler particles on the effective thermal conductivity for polymer composites. In the earlier models, less emphasis has been given on the shape of filler particle... The present paper deals with the effect of geometry of filler particles on the effective thermal conductivity for polymer composites. In the earlier models, less emphasis has been given on the shape of filler particles. In this paper, expressions for effective thermal conductivity has been derived using the law of minimal thermal resistance and equal law of the specific equivalent thermal conductivity for three different shapes i.e. spherical, elliptical and hexagonal of filler particles respectively. Calculated values of effective thermal conductivity for various samples using the derived expressions then compared with experimental data available and other models developed in the literature. The results calculated are in good agreement with the earlier experimental data and the deviation, is least in our expressions showing the success of the model. 展开更多
关键词 effective theRMAL CONDUCTIVITY Polymer Composites MINIMAL theRMAL resistance SHAPE of FILLER
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Monitoring of Respiratory Infections in the Intensive Area of Respiratory System Disease 被引量:1
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作者 Filippo Ricciardiello Maria Cardone +4 位作者 Giuseppe Fiorentino Massimo Mesolella Flavia Oliva Annalisa Pianese Carlo Antonio Leone 《Advances in Microbiology》 2014年第9期560-566,共7页
Respiratory infections are the most frequent nosocomial infections after those urinaries and surgicals. We analysed respiratory infection incidences in patients treated with different kinds of respiratory assistance (... Respiratory infections are the most frequent nosocomial infections after those urinaries and surgicals. We analysed respiratory infection incidences in patients treated with different kinds of respiratory assistance (non-invasive ventilation and invasive mechanical ventilation trough tracheostomy), studying 640 patients recovering in the intensive area of respiratory disease from 2010 to 2013. We had 113 cases of respiratory infections: 42.5% in patients of non-invasive ventilation group and 57.5% of patients treated with invasive ventilation with a statistically significant difference between the two groups. The patients treated with non-invasive ventilation showed a lower incidence of nosocomial respiratory infections. Prevention guidelines are important to reduce nosocomial infections frequency. 展开更多
关键词 INTENSIVE respiratory Area Multi-Resistant PATHOGENS NOSOCOMIAL INFECTIONS Pneumonias TRACHEOSTOMY
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Assessment of Bronchodilator Response in Children with Asthma Exacerbation Using the Respiratory Resistance Values
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作者 Maria V. Bautista Jafar Vossoughi +1 位作者 Arthur T. Johnson Martin Keszler 《Open Journal of Respiratory Diseases》 2021年第4期117-132,共16页
Sixty-four pediatric patients with asthma exacerbation were studied. The c</span><span style="font-family:""><span style="font-family:Verdana;">hildren were subjected to resp... Sixty-four pediatric patients with asthma exacerbation were studied. The c</span><span style="font-family:""><span style="font-family:Verdana;">hildren were subjected to respiratory resistance evaluation using the Airflow Perturbation Device (APD) and spirometry evaluation. They were then adminis</span><span style="font-family:Verdana;">tered albuterol and 15 minutes later the APD and spirometry evaluations w</span><span style="font-family:Verdana;">ere repeated. Eleven of the children could not perform spirometry. The APD re</span><span style="font-family:Verdana;">sults demonstrated that respiratory resistance of the patients decreased by a</span><span style="font-family:Verdana;">bout 20%, indicating that the APD could detect the expected response to bronchodilator. However, no similar conclusion could be made with the spirometry parameters (</span><span style="font-family:Verdana;">FVC, FEV1, FEV1/FVC, and FEF25% - 75%) performed on the same patients. The differences on the spirometry parameters did not change </span><span style="font-family:Verdana;">significantly before and after bronchodilator administration. Furthermore, th</span><span style="font-family:Verdana;">ese differences were negligibly increased or decreased for some with no consistency between the FVC, FEV1, FEV1/FVC, and FEF25% - 75%. Even though all the children were clinically improved after albuterol administration and discharged home, this could not be demonstrated by spirometry data. This study validates previous reports that spirometry is not a reliable pulmonary diagnostic tool for young children, as spirometry is highly effort-dependent and requires a substantial degree of patient cooperation. APD on the other hand is a reliable, simple, effortless diagnostic tool that can be utilized in evaluation and management of children with asthma symptoms and exacerbation. 展开更多
关键词 Pediatric Asthma respiratory resistance SPIROMETER ALBUTEROL
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A Systematic Study of the Forbidden Pitch in the CD Through-Pitch Curve for Beyond 130nm
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作者 赵宇航 朱骏 曹永峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期889-892,共4页
The forbidden pitch "dip" in the critical dimension (CD) through the pitch curve is a well-known optical proximity effect. The CD and CD process window near the "dip",usually found near a pitch range of 1.1 to 1... The forbidden pitch "dip" in the critical dimension (CD) through the pitch curve is a well-known optical proximity effect. The CD and CD process window near the "dip",usually found near a pitch range of 1.1 to 1.4 wavelength/ NA (numerical aperture),is smaller when compared with other pitches. This is caused by inadequate imaging contrast for an unequal line and space grating. Although this effect is relatively well-known, its relationship with typical process condition parameters,such as the effective image blur caused by the photo-acid diffusion during the post exposure bake or the aberration in the imaging lens, has not been systematically studied. In this paper, we will examine the correlation between the image blur and the effect on the CD, including the decrease in the CD value (the depth of the "dip") and the CD process window. We find that both the decrease in the CD value and the focus latitude near the forbidden pitch correlate very well with the effective Gaussian image blur. Longer effective diffusion length correlates well with a smaller process window and a deeper CD "dip". We conclude that the dip depth is very sensitive to the change in image contrast. 展开更多
关键词 forbidden pitch effective resist diffusion length OPC OAI deep-UV
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The mechanism underlying overwintering death in poplar:the cumulative effect of effective freeze-thaw damage 被引量:4
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作者 Chengchao Yang Jiandong Peng +3 位作者 Xiaoyu Li Dejun Liang Zhiyan Yang Yan Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期219-229,共11页
We analyzed the relationships linking overwintering death and frost cracking to temperature and sunlight as well as the effects of low temperatures and freeze–thaw cycles on bud-burst rates,relative electrical conduc... We analyzed the relationships linking overwintering death and frost cracking to temperature and sunlight as well as the effects of low temperatures and freeze–thaw cycles on bud-burst rates,relative electrical conductivity,and phloem and cambial ultrastructures of poplar.Overwintering death rates of poplar were not correlated with negative accumulated temperature or winter minimum temperature.Freeze–thaw cycles caused more bud damage than constant exposure to low temperatures.Resistance to freeze–thaw cycles differed among clones,and the budburst rate decreased with increasing exposure to freeze–thaw cycles.Cold-resistant clones had the lowest relative electrical conductivity.Chloroplasts exhibited the fastest and the most obvious reaction to freeze–thaw damage,whereas a single freeze–thaw cycle caused little damage to cambium ultrastructure.Several such cycles resulted in damage to plasma membranes,severe damage to organelles,dehydration of cells and cell death.We conclude that overwintering death of poplar is mainly attributed to the accumulation of effective freeze–thaw damage beyond the limits of freeze–thaw resistance. 展开更多
关键词 effective freeze–thaw Freeze–thaw resistance MECHANISM Overwintering death POPULUS Ultrastructure
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Thermal resistance matrix representation of thermal effects and thermal design of microwave power HBTs with two-dimensional array layout 被引量:2
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作者 Rui Chen Dong-Yue Jin +5 位作者 Wan-Rong Zhang Li-Fan Wang Bin Guo Hu Chen Ling-Han Yin Xiao-Xue Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第9期373-380,共8页
Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resist... Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resistance to describe the self-heating and thermal coupling effects, respectively.For HBT cells along the emitter length direction, the thermal coupling resistance is far smaller than the self-heating thermal resistance, and the peak junction temperature is mainly determined by the self-heating thermal resistance.However, the thermal coupling resistance is in the same order with the self-heating thermal resistance for HBT cells along the emitter width direction.Furthermore, the dependence of the thermal resistance matrix on cell spacing along the emitter length direction and cell spacing along the emitter width direction is also investigated, respectively.It is shown that the moderate increase of cell spacings along the emitter length direction and the emitter width direction could effectively lower the self-heating thermal resistance and thermal coupling resistance,and hence the peak junction temperature is decreased, which sheds light on adopting a two-dimensional non-uniform cell spacing layout to improve the uneven temperature distribution.By taking a 2 × 6 HBTs array for example, a twodimensional non-uniform cell spacing layout is designed, which can effectively lower the peak junction temperature and reduce the non-uniformity of the dissipated power.For the HBTs array with optimized layout, the high power-handling capability and thermal dissipation capability are kept when the bias voltage increases. 展开更多
关键词 HETEROJUNCTION BIPOLAR transistors(HBTs) array theRMAL effects theRMAL resistance MATRIX theRMAL design
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Synthesis and Performance of an Associative Anti-shear Drag Reducer Based on Hydrogen Bond Association of Dodecyl Methacrylate
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作者 Lu Yong Li Chenhao +5 位作者 Li Hao Chen Yue Xu Dan Wang Yiran Meng Yeqiao Zhang Xiaolai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第1期23-33,共11页
Using K2S2O8-Na2SO3 as the redox initiation system,a hydrogen-bond-association-based dodecyl methacrylate system associative anti-shear drag reducer was synthesised by standard emulsion polymerisation.The reaction pro... Using K2S2O8-Na2SO3 as the redox initiation system,a hydrogen-bond-association-based dodecyl methacrylate system associative anti-shear drag reducer was synthesised by standard emulsion polymerisation.The reaction process was simple and gentle as well as safe and stable.Molecular design was carried out using molecular dynamics simulation methods.The results of infrared spectroscopy,thermogravimetric analysis,differential scanning calorimetry,gel chromatography,and laser light scattering showed that the reaction polymerisation was relatively complete,the product was uniform,the molecular weight distribution was controllable,and the synthesised polymer had good flexibility.The donor lauryl methacrylate-styrene-methacrylic acid(LMA-St-MAA)and acceptor lauryl methacrylate-styrene-dimethylaminoethyl methacrylate(LMA-St-DMA)polymers had an associative intermolecular interaction force,which increased the molecular cluster size of the associative system complex.The complex had good shear resistance,and the test results of the tube pump shear test showed that the synthesised associative oil-soluble polymer drag reduction system exhibited better drag reduction rate performance than poly-α-olefins over repeated cycles.The research results provide a reference plan for minimising the number of station-to-station inputs,thereby ensuring the stability of oil pipelines and reducing transportation costs. 展开更多
关键词 drag reducer associative effect drag reduction rate shear resistance
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Effects of Irregular Respiratory Motion on the Positioning Accuracy of Moving Target with Free Breathing Cone-Beam Computerized Tomography 被引量:1
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作者 Xiang Li Tianfang Li +9 位作者 Ellen Yorke Gig Mageras Xiaoli Tang Maria Chan Weijun Xiong Marsha Reyngold Richard Gewanter Abraham Wu John Cuaron Margie Hunt 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第2期173-183,共11页
For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT ... For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT (FBCBCT) before treatment. This method can be highly accurate if the respiratory motion of the patient is stable. However, a patient’s breathing pattern is often irregular. The purpose of this study is to investigate the effects of irregular respiration on positioning accuracy for a moving target aligned with FBCBCT. Nine patients’ respiratory motion curves were selected to drive a Quasar motion phantom with one embedded cubic and two spherical targets. A 4DCT of the phantom was acquired on a CT scanner (Philips Brilliance 16) equipped with a Varian RPM system. The phase binned 4DCT images and the corresponding MIP and AIP images were transferred into Eclipse for analysis. FBCBCTs of the phantom driven by the same respiratory curves were also acquired on a Varian TrueBeam and fused such that both CBCT and MIP/AIP images share the same target zero positions. The sphere and cube volumes and centroid differences (alignment error) determined by MIP, AIP and FBCBCT images were calculated, respectively. Compared to the volume determined by MIP, the volumes of the cube, large sphere, and small sphere in AIP and FBCBCT images were smaller. The alignment errors for the cube, large sphere and small sphere with center to center matches between MIP and FBCBCT were 2.5 ± 1.8 mm, 2.4 ± 2.1 mm, and 3.8 ± 2.8 mm, and the alignment errors between AIP and FBCBCT were 0.5 ± 1.1 mm, 0.3 ± 0.8 mm, and 1.8 ± 2.0 mm, respectively. AIP images appear to be superior reference images to MIP images. However, irregular respiratory pattern could compromise the positioning accuracy, especially for smaller targets. 展开更多
关键词 CONE Beam COMPUTERIZED TOMOGRAPHY respiratory Motion Effect
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Study on the formation of arc plasma on the resistive wall liquid metal current limiter
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作者 李金金 段雄英 +4 位作者 黄智慧 谢为赢 廖敏夫 马畅 陶佳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期141-152,共12页
Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designe... Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designed to advance the starting current-limiting time.Experiments are performed to investigate the dynamic behaviors of liquid metal,and the influence of different currents on the liquid metal self-shrinkage effect is compared and analyzed.Furthermore,the liquid metal self-shrinkage effect is mathematically modeled,and the reason for the formation of arc plasma is obtained by simulation.The laws of arc plasma formation and the current transfer in the cavity are revealed,and the motion mechanisms are explained by physical principles.The simulations are in accordance with the test data.It is demonstrated that the sudden change of the current density at both ends of the wall causes the liquid metal to shrink and depress under the electromagnetic force,and the current starts to transfer from the liquid metal path to the wall resistance path.The RWLMCL can effectively advance the starting current-limiting time. 展开更多
关键词 resistive wall liquid metal current limiter(RWLMCL) liquid metal self-shrinkage effect arc plasma current transfer
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