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Hydraulic and volume change behaviors of compacted highly expansive soil under cyclic wetting and drying 被引量:4
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作者 Mohamed Farid Abbas Abdullah Ali Shaker Mosleh A.Al-Shamrani 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期486-499,共14页
The wide engineered application of compacted expansive soils necessitates understanding their behavior under field conditions.The results of this study demonstrate how seasonal climatic variation and stress and bounda... The wide engineered application of compacted expansive soils necessitates understanding their behavior under field conditions.The results of this study demonstrate how seasonal climatic variation and stress and boundary conditions individually or collectively influence the hydraulic and volume change behavior of compacted highly expansive soils.The cyclic wetting and drying(CWD)process was applied for two boundary conditions,i.e.constant stress(CS)and constant volume(CV),and for a wide range of axial stress states.The adopted CWD process affected the hydraulic and volume change behaviors of expansive soils,with the first cycle of wetting and drying being the most effective.The CWD process under CS conditions resulted in shrinkage accumulation and reduction in saturated hydraulic conductivity(k sat).On the other hand,CWD under CV conditions caused a reduction of swell pressure while has almost no impact on k sat.An elastic response to CWD was achieved after the third cycle for saturated hydraulic conductivity(k sat),the third to fourth cycle for the volume change potential under the CV conditions,and the fourth to fifth cycle for the volume change potential under the CS conditions.Finally,both swell pressure(s s)and saturated hydraulic conductivity(k sat)are not fundamental parameters of the expansive soil but rather depend on stress,boundary and wetting conditions. 展开更多
关键词 Expansive soils Hydraulic conductivity volume change potential Cyclic wetting and drying(CWD) Swell pressure
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Influence of vapor pressure deficit on vegetation growth in China 被引量:1
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作者 LI Chuanhua ZHANG Liang +3 位作者 WANG Hongjie PENG Lixiao YIN Peng MIAO Peidong 《Journal of Arid Land》 SCIE CSCD 2024年第6期779-797,共19页
Vapor pressure deficit(VPD)plays a crucial role in determining plant physiological functions and exerts a substantial influence on vegetation,second only to carbon dioxide(CO_(2)).As a robust indicator of atmospheric ... Vapor pressure deficit(VPD)plays a crucial role in determining plant physiological functions and exerts a substantial influence on vegetation,second only to carbon dioxide(CO_(2)).As a robust indicator of atmospheric water demand,VPD has implications for global water resources,and its significance extends to the structure and functioning of ecosystems.However,the influence of VPD on vegetation growth under climate change remains unclear in China.This study employed empirical equations to estimate the VPD in China from 2000 to 2020 based on meteorological reanalysis data of the Climatic Research Unit(CRU)Time-Series version 4.06(TS4.06)and European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis 5(ERA-5).Vegetation growth status was characterized using three vegetation indices,namely gross primary productivity(GPP),leaf area index(LAI),and near-infrared reflectance of vegetation(NIRv).The spatiotemporal dynamics of VPD and vegetation indices were analyzed using the Theil-Sen median trend analysis and Mann-Kendall test.Furthermore,the influence of VPD on vegetation growth and its relative contribution were assessed using a multiple linear regression model.The results indicated an overall negative correlation between VPD and vegetation indices.Three VPD intervals for the correlations between VPD and vegetation indices were identified:a significant positive correlation at VPD below 4.820 hPa,a significant negative correlation at VPD within 4.820–9.000 hPa,and a notable weakening of negative correlation at VPD above 9.000 hPa.VPD exhibited a pronounced negative impact on vegetation growth,surpassing those of temperature,precipitation,and solar radiation in absolute magnitude.CO_(2) contributed most positively to vegetation growth,with VPD offsetting approximately 30.00%of the positive effect of CO_(2).As the rise of VPD decelerated,its relative contribution to vegetation growth diminished.Additionally,the intensification of spatial variations in temperature and precipitation accentuated the spatial heterogeneity in the impact of VPD on vegetation growth in China.This research provides a theoretical foundation for addressing climate change in China,especially regarding the challenges posed by increasing VPD. 展开更多
关键词 vapor pressure deficit(VPD) near-infrared reflectance of vegetation(NIRv) leaf area index(LAI) gross primary productivity(GPP) Climatic Research Unit(CRU)Time-Series version 4.06(TS4.06) European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis 5(ERA-5) climate change
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Effect of Climate Change on Lung Cancer
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作者 Shivansh Sharma 《Health》 2024年第1期60-71,共12页
This research paper aims to draw a relationship between lung cancer and climate change. With the rise of climate change in the last few decades, many organizations and people are concerned about the future of the worl... This research paper aims to draw a relationship between lung cancer and climate change. With the rise of climate change in the last few decades, many organizations and people are concerned about the future of the world. Climate change has many side effects, such as air pollution, which can increase the incidence and death rates of lung and bronchus cancer. This paper aims to draw the relationship between climate change factors and lung cancer incidence and mortality rates. The main finding of this analysis was that there is a positive relationship between lung cancer incidence, death rates, and climate change indicators. The findings from this study have the potential to inform targeted public health interventions and policies, emphasizing the need for proactive strategies in mitigating the health impacts of a changing climate. Section 2 of this paper is a literature review and focuses on the findings of other scholars in this field. Section 3 of this paper is Methods and Processes and will highlight the steps used to create the program and get the results. Section 4 of this paper is Results and Analysis, and will go over the results produced by the machine learning algorithm, and will present graphs and visualizations regarding the relationship of the dependent and independent variables. The final section, Section 5, is Limitations and Conclusion, in which we will discuss possible limitations to both my dataset and my model, and will conclude the paper by presenting a big-picture view of these problems in our society. 展开更多
关键词 CANCER lung Cancer Climate change
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Pathological changes in the lung and brain of mice during heat stress and cooling treatment 被引量:10
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作者 Zhi-feng Liu Bing-ling Li +4 位作者 Hua-sheng Tong You-qing Tang Qiu-lin Xu Jin-qiang Guo Lei Su 《World Journal of Emergency Medicine》 CAS 2011年第1期50-53,共4页
BACKGROUND: Heatstroke often leads to multiple organ dysfunction syndrome (MODS) with a death rate of 40% or a neurological morbidity of 30%. These high rates in patients with heatstroke are largely due to the prog... BACKGROUND: Heatstroke often leads to multiple organ dysfunction syndrome (MODS) with a death rate of 40% or a neurological morbidity of 30%. These high rates in patients with heatstroke are largely due to the progression of heat stress to MODS, resulting in no specifi c treatment available. This study aimed to develop a mouse model of heat stress and determine the pathological changes in the lung and brain during heat stress and cooling treatment.METHODS: A mouse model of heat stress was established in a pre-warmed incubator set at 35.5 ± 0.5°C and with a relative humidity of 60% ± 5%. Rectal temperature was monitored, and at a temperature of 39 °C, 40 °C, 41 °C, or 42 °C, the mice were sacrifi ced. The remaining animals were removed from the incubator and cooled at an ambient temperature of 25 ± 0.5 °C and a humidity of 35% ± 5% for 12 or 24 hours at a temperature of 41 °C or for 6 hours at a temperature of 42 °C. The control mice were sham-heated at a temperature of 25 ± 0.5 °C and a humidity of 35% ± 5%. The lungs and brains of all animals were isolated. Hematoxylin and eosin staining and light microscopy were performed to detect pathological changes.RESULTS: All mice demonstrated a uniform response to heat stress. A low degree of heat stress induced marked pathological changes of the lungs. With the rise of the temperature to 42°C, progressively greater damage to the lungs with further congestion of the lung matrix, asystematic hemorrhage of alveolar space, abscission of alveolar epithelial cells, and disappearance of pulmonary alveolus tissue structure were detected. However, absorption of congestion and hemorrhage as well as recovery of pulmonary alveolus tissue structure was observed following cooling treatment at an ambient temperature. With a low degree of heat stress, the brain only showed moderate edema. Neuronal denaturation and necrosis were detected at a temperature of 42°C. Interestingly, the lesions in the brain were further aggravated at 42 °C regardless of cooling treatment, but recovery was observed after cooling treatment at 41 °C.CONCLUSIONS: The pathological changes of the lungs and brain of mice showed distinctive lesions following heat stress and cooling treatment, and they were correlated with the time and duration of cooling treatment. The results of this study are helpful for further study of the mechanisms linking heatstroke. 展开更多
关键词 Heat stress HEATSTROKE Cooling treatment lung BRAin Pathological change MODS
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Associations of soybean products intake with blood pressure changes and hypertension incidence: the China-PAR project 被引量:3
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作者 Jia-Liu WEI Xin-Yan WANG +9 位作者 Fang-Chao LIU Ji-Chun CHEN Jie CAO Jian-Xin LI Dong-Sheng HU Chong SHEN Fang-Hong LU Ying-Xin ZHAO Jian-Feng HUANG Xiang-Feng LU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第7期384-392,共9页
Background The relationships between dietary intake of soybean products and incident hypertension were still uncertain.This study aimed to illustrate the associations between intake of soybean products with risks of i... Background The relationships between dietary intake of soybean products and incident hypertension were still uncertain.This study aimed to illustrate the associations between intake of soybean products with risks of incident hypertension and longitudinal changes of blood pressure in a prospective cohort study.Methods We included 67,499 general Chinese adults from the Project of Prediction for Atherosclerosis Cardiovascular Disease Risk in China(China-PAR).Information about soybean products consumption was collected by standardized questionnaires,and study participants were categorized into the ideal(≥125 g/day)or non-ideal(<125 g/day)group.Hazard ratios(HRs)and corresponding 95%confidence intervals(95%CIs)for incident hypertension were calculated using Cox proportional hazard models.Among participants with repeated measures of blood pressure,generalized linear models were used to examine the relationships between soybean products consumption and blood pressure changes.Results During a median follow-up of 7.4 years,compared with participants who consumed<125 g of soybean products per day,multivariable adjusted HR for those in the ideal group was 0.73(0.67-0.80).This inverse association remained robust across most subgroups while significant interactions were tested between soybean products intake and age,sex,urbanization and geographic region(P values for interaction<0.05).The mean systolic and diastolic blood pressure levels were 1.05(0.71-1.39)mmHg and 0.44(0.22-0.66)mmHg lower among participants in the ideal group than those in the non-ideal group.Conclusions Our study showed that intake of soybean products might reduce the long-term blood pressure levels and hypertension incidence among Chinese population,which has important public health implications for primary prevention of hypertension. 展开更多
关键词 Blood pressure changes Chinese population Cohort study HYPERTENSION Soybean products
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Effect of change in large and fast solar wind dynamic pressure on geosynchronous magnetic field 被引量:1
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作者 Borodkova 刘静波 +3 位作者 黄朝晖 Zastenker G N 王赤 Eiges P E 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2458-2464,共7页
We present a comparison of changes in large and sharp solar wind dynamic pressure, observed by several spacecraft, with fast disturbances in the magnetospheric magnetic field, measured by the geosynchronous satellites... We present a comparison of changes in large and sharp solar wind dynamic pressure, observed by several spacecraft, with fast disturbances in the magnetospheric magnetic field, measured by the geosynchronous satellites. More than 260 changes in solar wind pressure during the period 1996-2003 are selected for this study. Large statistics show that an increase (a decrease) in dynamic pressure always results in an increase (a decrease) in the magnitude of geosynchronous magnetic field. The amplitude of response to the geomagnetic field strongly depends on the location of observer relative to the noon meridian, the value of pressure before disturbance, and the change in amplitude of pressure. 展开更多
关键词 solar wind dynamic pressure changes geosynchronous magnetic field
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Mechanical effects of circular liquid inclusions inside soft matrix:role of internal pressure change and surface tension 被引量:1
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作者 Lei ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第4期501-510,共10页
The mechanical effects of dilute liquid inclusions on the solid-liquid composite are explored,based on an analytical circular inclusion model incorporating the internal pressure change of the liquid and the surface te... The mechanical effects of dilute liquid inclusions on the solid-liquid composite are explored,based on an analytical circular inclusion model incorporating the internal pressure change of the liquid and the surface tension of the interface.Several simple explicit dependences of the stress field and effective stiffness on the bulk modulus and the size of the liquid,the surface tension,and Poisson’s ratio of the matrix are derived.The results show that the stresses in the matrix are reduced,and the stiffness of the solid-liquid composite is enhanced with the consideration of either the surface tension or the internal pressure change.Particularly,the effective Young’s modulus predicted by the present model for either soft or stiff matrices agrees well with the known experimental data.In addition,according to the theoretical results,it is possible to stiffen a soft solid by pressured gas with the presence of the surface tension of the solid-gas interface. 展开更多
关键词 liquid inclusion stress field effective stiffness surface tension internal pressure change
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Modeling the Pressure Distribution and the Changes of Water Level around the Offshore Platforms Exposed to Waves, Using the Numerical Model of Flow 3D 被引量:1
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作者 Milad Rashidinasab Mehdi Behdarvandi Askar 《Computational Water, Energy, and Environmental Engineering》 2017年第1期97-106,共10页
The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures... The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures from different aspects and perspectives, we would have to evaluate many different parameters about them. So categorizing these parameters can help to perform their related analysis with more accuracy and more details. Due to the efficient force it exerts on the structure, the pressure distribution around every marine or hydraulic structure has a significant importance, and it even accounts for one of the dominant issues in designing and building of such structures. In the present study, an oil platform located in Phase 15 of South Pars oil fields, located in the Persian Gulf waters, has been analyzed using the FLOW 3D software. The outputs indicate that the pressure of water is distributed almost hydrostatically with the depth, and its maximum reaches 0.6 MPa at the bottom. 展开更多
关键词 pressure Distribution ofFSHORE PLATFORMS changeS of Water Level MODELinG
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Visualizing Relationships between Drivers of Environmental Change and Pressures on Land-Based Ecosystems 被引量:1
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作者 Jason Jabbour Carol Hunsberger 《Natural Resources》 2014年第4期146-160,共15页
The pursuit of human needs and demands is placing more pressure on land resources than ever before. The challenge of feeding 7 billion people is increasingly competing with rising demands for materials and biofuels. D... The pursuit of human needs and demands is placing more pressure on land resources than ever before. The challenge of feeding 7 billion people is increasingly competing with rising demands for materials and biofuels. Deforestation and land degradation are among the pressing outcomes of these trends. Drivers of environmental change—including population growth, economic activity, consumption, urbanization, trade, conflict, and governance—clearly play a role in aggravating or mitigating these pressures on land. Despite advances in understanding causality in complex systems, navigating the interactions between these drivers remains a major challenge. This paper analyzes and visualizes the relationships between multiple, interacting drivers of environmental change and specific pressures on land-based ecosystems. Drawing on experience from the development of the Drivers and Land chapters of the UN Environment Programme’s Fifth Global Environment Outlook report (GEO-5), we use a series of Kiviat diagrams to illustrate the relative influence of key drivers on selected pressures on land. When individual diagrams are overlaid, patterns of influence emerge that can provide insight into where policy responses might best be targeted. We propose that, subject to some limitations, the Kiviat exercise can provide an accessible and potentially valuable “knowledge-intermediary” tool to help link science-based information to policy action. 展开更多
关键词 DRIVERS ENVIRONMENTAL pressure Land Use change integrated Assessment Science-Policy
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Biomolecular changes and DNA targeting effect of sesamol in human lung adenocarcinoma (SK-LU-1) cells by FTIR microscopy
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作者 Boondaree Siriwarin Natthida Weerapreeyakul +1 位作者 Waraporn Tanthanuch Kanjana Thumanu 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2018年第8期377-386,共10页
Objective: To investigate biomolecular alteration of sesamol on human lung adenocarcinoma(SK-LU-1) cells compared with cisplatin using Fourier transform infrared microscopy(FTIR). Methods: Cytotoxicity of sesamol was ... Objective: To investigate biomolecular alteration of sesamol on human lung adenocarcinoma(SK-LU-1) cells compared with cisplatin using Fourier transform infrared microscopy(FTIR). Methods: Cytotoxicity of sesamol was investigated against SK-LU-1 cells by using neutral red. DNA fragmentation and the cell cycle analysis were determined by agarose gel electrophoresis and flow cytometry, respectively. The FTIR microscopy technique was applied to explore the changes in cellular biochemical compositions in cells treated with sesamol that the biochemical and biological assays cannot cover. The alkylating property was determined by 4-(4-nitrobenzyl)pyridine assay. Results: Sesamol and cisplatin exerted an antiproliferative effect at 48 h with respective IC50 values of 2.7 and 0.07 m M. Both induced apoptosis by causing DNA damage and accumulation of cell populations at sub-G1. FTIR microscopy and Principle Component Analysis clearly discriminated the sesamol-and cisplatin-treated cells from the untreated cells or control. A significant increase of total lipid content was found in cisplatin-treated cells. Conformational changes in the proteins secondary structure from the β-helix to the β-sheet were found in both sesamol-and cisplatin-treated cells, as well as significant reductions in relative DNA content of both compared to the control were observed, suggesting DNA damage. A shift in the peak position of DNA region provides insight on the DNA interactions. Conclusions: The non-alkylating effect of sesamol based on the nitrobenzyl pyridine assay delineates the non-covalent binding mode of sesamol on DNA. Hydrogen bonding is the binding mode of sesamol on DNA, while for cisplatin it was covalent and hydrogen bonding. 展开更多
关键词 FTIR microscopy SESAMOL CISPLATin lung adenocarcinoma Biomolecular change
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Effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia 被引量:1
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作者 Chang-Hao Yao Zhao-Hua Dai Rui-Li Chai 《Journal of Hainan Medical University》 2017年第22期87-90,共4页
Objective: To discuss the effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe p... Objective: To discuss the effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia. Methods: A total of 68 patients with COPD complicated by severe pneumonia who were treated in the hospital between November 2015 and April 2017 were collected, retrospectively analyzed and then divided into the group A (n=35) who received noninvasive positive pressure ventilation and the group B (n=33) who received lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation. The differences in arterial blood gas and serum index levels were compared between the two groups before and after treatment. Results: Before treatment, there was no statistically significant difference in arterial blood gas index levels as well as serum contents of inflammatory mediators, stress hormones and myocardial enzyme spectrum indexes between the two groups. After treatment, arterial blood gas indexes PH and PaO2 levels of group B were higher than those of group A;serum inflammatory mediators HMGB1, PCT and hs-CRP contents were lower than those of group A;serum stress hormones Cor, AngⅠ and AngⅡcontents were lower than those of group A;serum myocardial enzyme spectrum indexesα-HBDH and cTn-Ⅰ contents were lower than those of group A. Conclusion: Lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation can effectively optimize the arterial blood gas levels, reduce systemic inflammatory stress state and protect the myocardial function of patients with COPD complicated by severe pneumonia. 展开更多
关键词 COPD Severe PNEUMONIA Non-invasive positive pressure ventilation lung LAVAGE VIA FIBER BRONCHOSCOPE
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Dosimetric consequences of tumor volume changes after kilovoltage cone-beam computed tomography for non-operative lung cancer during adaptive intensity-modulated radiotherapy or fractionated stereotactic radiotherapy
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作者 Jian Hu Ximing Xu +4 位作者 Guangjin Yuan Wei Ge Liming Xu Aihua Zhang Junjian Deng 《Oncology and Translational Medicine》 CAS 2015年第5期195-200,共6页
Objective The aim of this study was to investigate tumor volume changes with kilovoltage cone-beam computed tomography (kV-CBCT) and their dosimetric consequences for non-operative lung cancer during intensity-modul... Objective The aim of this study was to investigate tumor volume changes with kilovoltage cone-beam computed tomography (kV-CBCT) and their dosimetric consequences for non-operative lung cancer during intensity-modulated radiotherapy (IMRT) or fractionated stereotactic radiotherapy. Methods Eighteen patients with non-operative lung cancer who received IMRT consisting of 1.8-2.2 Gy/fraction and five fractions per week or stereotactic radiotherapy with 5-8 Gy/fraction and three fractions a week were studied, kV-CBCT was performed once per week during IMRT and at every fraction during stereotactic radiotherapy. The gross tumor volume (GTV) was contoured on the kV-CBCT images, and adaptive treatment plans were created using merged kV-CBCT and primary planning computed tomogra- phy image sets. Tumor volume changes and dosimetric parameters, including the minimum dose to 95% (D95) or 1% (D1) of the planning target volume (PTV), mean lung dose (MLD), and volume of lung tissue that received more than 5 (Vs), 10 (Vl0), 20 (V20), and 30 (V30) Gy were retrospectively analyzed. Results The average maximum change in GTV observed during IMRT or fractionated stereotactic radio- therapy was -25.85% (range, -13.09% --56.76%). The D95 and Dr of PTV for the adaptive treatment plans in all patients were not significantly different from those for the initial or former adaptive treatment plans. In patients with tumor volume changes of 〉20% in the third or fourth week of treatment during IMRT, adap- tive treatment plans offered clinically meaningful decreases in MLD and V5, V10, V20, and V30; however, in patients with tumor volume changes of 〈 20% in the third or fourth week of treatment as well as in patients with stereotactic radiotherapy, there were no significant or clinically meaningful decreases in the dosimetric parameters. Conclusion Adaptive treatment planning for decreasing tumor volume during IMRT may be beneficial for patients who experience tumor volume changes of 〉20% in the third or fourth week of treatment. 展开更多
关键词 lung cancer kilovoltage cone-beam computed tomography (kV-CBCT) intensity-modulated radiotherapy (IMRT) stereotactic radiotherapy tumor changes adaptive planning
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Driving pressure in mechanical ventilation:A review 被引量:2
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作者 Syeda Farheen Zaidi Asim Shaikh +2 位作者 Daniyal Aziz Khan Salim Surani Iqbal Ratnani 《World Journal of Critical Care Medicine》 2024年第1期15-27,共13页
Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP lev... Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP levels have also been shown to closely impact hard endpoints such as mortality.Considering this,conducting an in-depth review ofΔP as a unique,outcome-impacting therapeutic modality is extremely important.There is a need to understand the subtleties involved in making sureΔP levels are optimized to enhance outcomes and minimize harm.We performed this narrative review to further explore the various uses ofΔP,the different parameters that can affect its use,and how outcomes vary in different patient populations at different pressure levels.To better utilizeΔP in MV-requiring patients,additional large-scale clinical studies are needed. 展开更多
关键词 Driving pressure Acute respiratory distress syndrome MORTALITY Positive end-expiratory pressure Ventilator induced lung injury Mechanical ventilation
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Driving pressure decoded:Precision strategies in adult respiratory distress syndrome management
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作者 Muhammad Adrish Sai Doppalapudi Dmitry Lvovsky 《World Journal of Critical Care Medicine》 2024年第2期15-18,共4页
Mechanical ventilation(MV)is an important strategy for improving the survival of patients with respiratory failure.However,MV is associated with aggravation of lung injury,with ventilator-induced lung injury(VILI)beco... Mechanical ventilation(MV)is an important strategy for improving the survival of patients with respiratory failure.However,MV is associated with aggravation of lung injury,with ventilator-induced lung injury(VILI)becoming a major concern.Thus,ventilation protection strategies have been developed to minimize complications from MV,with the goal of relieving excessive breathing workload,improving gas exchange,and minimizing VILI.By opting for lower tidal volumes,clinicians seek to strike a balance between providing adequate ventilation to support gas exchange and preventing overdistension of the alveoli,which can contribute to lung injury.Additionally,other factors play a role in optimizing lung protection during MV,including adequate positive end-expiratory pressure levels,to maintain alveolar recruitment and prevent atelectasis as well as careful consideration of plateau pressures to avoid excessive stress on the lung parenchyma. 展开更多
关键词 Driving pressure Mechanical ventilation lung-protective ventilation strategies Ventilator-induced lung injury
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Driving pressure:A useful tool for reducing postoperative pulmonary complications
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作者 Domenico Posa Fabio Sbaraglia +1 位作者 Giuliano Ferrone Marco Rossi 《World Journal of Critical Care Medicine》 2024年第3期91-94,共4页
The operating room is a unique environment where surgery exposes patients to non-physiological changes that can compromise lung mechanics.Therefore,raising clinicians’awareness of the potential risk of ventilator-ind... The operating room is a unique environment where surgery exposes patients to non-physiological changes that can compromise lung mechanics.Therefore,raising clinicians’awareness of the potential risk of ventilator-induced lung injury(VILI)is mandatory.Driving pressure is a useful tool for reducing lung complications in patients with acute respiratory distress syndrome and those undergoing elective surgery.Driving pressure has been most extensively studied in the context of single-lung ventilation during thoracic surgery.However,the awareness of association of VILI risk and patient positioning(prone,beach-chair,parkbench)and type of surgery must be raised. 展开更多
关键词 Ventilator-induced lung injury Protective ventilation Driving pressure Mechanical ventilation Surgery room Single-lung ventilation Operative room SURGERY
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Correlation between blood pressure changes and AMS, sleeping quality and exercise upon high-altitude exposure in young Chinese men 被引量:6
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作者 Yang Liu Ji-Hang Zhang +6 位作者 Xu-Bin Gao Xiao-Jing Wu Jie Yu Jian-Fei Chen Shi-Zhu Bian Xiao-Han Ding Lan Huang 《Journal of Medical Colleges of PLA(China)》 CAS 2014年第2期89-97,共9页
Background: Excessive elevation of arterial blood pressure(BP) at high altitude can be detrimental to our health due to acute mountain sickness(AMS) or some AMS symptoms. This prospective and observational study aimed... Background: Excessive elevation of arterial blood pressure(BP) at high altitude can be detrimental to our health due to acute mountain sickness(AMS) or some AMS symptoms. This prospective and observational study aimed to elucidate blood pressure changes induced by exposure to high-altitude hypoxia and the relationships of these changes with AMS prevalence, AMS severity, sleep quality and exercise condition in healthy young men.Methods: A prospective observational study was performed in 931 male young adults exposed to high altitude at 3,700 m(Lhasa) from low altitude(LA, 500 m). Blood pressure measurement and AMS symptom questionnaires were performed at LA and on day 1, 3, 5, and 7 of exposure to high altitude. Lake Louise criteria were used to diagnose AMS. Likewise, the Athens Insomnia Scale(AIS) and the Epworth Sleepiness Scale(ESS) were filled out at LA and on day 1, 3, and 7 of exposure to high altitude.Results: After acute exposure to 3,700 m, diastolic blood pressure(DBP) and mean arterial blood pressure(MABP) rose gradually and continually(P【0.05). Analysis showed a relationship with AMS for only MABP(P【0.05) but not for SBP and DBP(P】0.05). Poor sleeping quality was generally associated with higher SBP or DBP at high altitude, although inconsistent results were obtained at different time(P【0.05). SBP and Pulse BP increased noticeably after high-altitude exercise(P【0.05).Conclusions: Our data demonstrate notable blood pressure changes under exposure to different high-altitude conditions: 1) BP increased over time. 2) Higher BP generally accompanied poor sleeping quality and higher incidence of AMS. 3) SBP and Pulse BP were higher after high-altitude exercise. Therefore, we should put more effort into monitoring BP after exposure to high altitude in order to guard against excessive increases in BP. 展开更多
关键词 arterial blood pressure changes high altitude acute mountain sickness sleep quality EXERCISE
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In vivo imaging of structural,metabolic and functional brain changes in glaucoma 被引量:3
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作者 Anisha Kasi Muneeb A.Faiq Kevin C.Chan 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期446-449,共4页
Glaucoma, the world's leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress ev... Glaucoma, the world's leading cause of irreversible blindness, is a condition for which elevated intraocular pressure is currently the only modifiable risk factor. However, the disorder can continue to progress even at reduced intraocular pressure. This indicates additional key factors that contribute to the etiopathogenesis. There has been a growing amount of literature suggesting glaucoma as a neurodegenerative disease of the visual system. However, it remains debatable whether the observed pathophysiological conditions are causes or consequences. This review summarizes recent in vivo imaging studies that helped advance the understanding of early glaucoma involvements and disease progression in the brains of humans and experimental animal models. In particular, we focused on the non-invasive detection of early structural and functional brain changes before substantial clinical visual field loss in glaucoma patients; the eye-brain interactions across disease severity; the metabolic changes occurring in the brain's visual system in glaucoma; and, the widespread brain involvements beyond the visual pathway as well as the potential behavioral relevance. If the mechanisms of glaucomatous brain changes are reliably identified, novel neurotherapeutics that target parameters beyond intraocular pressure lowering can be the promise of the near future, which would lead to reduced prevalence of this irreversible but preventable disease. 展开更多
关键词 GLAUCOMA inTRAOCULAR pressure eye-brain-behavior relationship irreversible BLinDNESS magnetic resonance imaging METABOLIC BRAin changeS sensitivity disease progression
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Pressure waves acting on wall of a tunnel and their impact on the tunnel's structural safety 被引量:5
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作者 LIU Tang-hong WANG Lei +3 位作者 LI Li YANG Fan CHEN Zheng-wei LIU Hong-kang 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第10期3223-3237,共15页
The transient pressures induced by trains passing through a tunnel and their impact on the structural safety of the tunnel lining were numerically analyzed.The results show that the pressure change increases rapidly a... The transient pressures induced by trains passing through a tunnel and their impact on the structural safety of the tunnel lining were numerically analyzed.The results show that the pressure change increases rapidly along the tunnel length,and the maximum value is observed at around 200 m from the entrance,while the maximum pressure amplitude is detected at 250 m from the entrance when two trains meeting in a double-track tunnel.The maximum peak pressure on the tunnel induced by a train passing through a 70 m^(2) single-track tunnel,100 m^(2) double-track tunnel and two trains meeting in the 100 m^(2) double-track tunnel at 350 km/h,are−4544 Pa,−3137 Pa and−5909 Pa,respectively.The aerodynamic pressure induced axial forces acting on the tunnel lining are only 8%,5%and 9%,respectively,of those generated by the earth pressure.It seems that the aerodynamic loads exert little underlying influence on the static strength safety of the tunnel lining providing that the existing cracks and defects are not considered. 展开更多
关键词 high-speed train TUNNEL pressure change tunnel lining structural safety
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Application of Negative Pressure Manual Dressing Change Combined with Mupirocin Ointment in the Treatment of a Case of a Patient with Cirrhosis Complicated with Deep Thigh Abscess 被引量:1
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作者 Yingying Meng Wali Lukman Ahmed Jian Luo 《Journal of Biosciences and Medicines》 2020年第5期113-121,共9页
Objective: To explore the treatment and nursing characteristics for pressure injury on the inside of the thigh caused by forced posture in patients with cirrhosis and diabetes mellitus. Methods: A patient with cirrhos... Objective: To explore the treatment and nursing characteristics for pressure injury on the inside of the thigh caused by forced posture in patients with cirrhosis and diabetes mellitus. Methods: A patient with cirrhosis and diabetes mellitus complicated with abscess of right inner thigh pressure injury was selected as the study object, who was admitted to Xuzhou Medical University Hospital on June 29, 2019. The analysis of the clinical diagnosis, treatment and nursing process were applied to explore the prognosis of the patient with cirrhosis and diabetes mellitus complicated with deep abscess of the thigh. Results: The traditional treatment including incision and drainage was not allowed, as the general treatment was not effective for the patients with cirrhosis and diabetes mellitus complicated with deep abscess in the inner thigh. After 8 days of negative pressure manual dressing change combined with mupirocin ointment treatment, the local skin condition returned to normal. Conclusion: After literature search, it was found that the above-mentioned cirrhosis combined with diabetes and deep abscess cases in the inner thigh were rare clinically. When the traditional treatment of incision and drainage is limited, negative pressure manual dressing change combined with antibiotics is an effective method, which is worthy of clinical application and promotion. 展开更多
关键词 CIRRHOSIS Diabetes Mellitus pressure injury DEEP Tissue ABSCESS Negative pressure DRESSinG change
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Disadvantage Pressure Changes on the Decline of Water Quality in Water Distribution Systems 被引量:1
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作者 Hossein Shamsaei Othman Jaafar Noor Ezlin Ahmad Basri 《Engineering(科研)》 2013年第1期97-105,共9页
Systems that have big transmission line may have problem on changes of pressure in the distribution system. Because pressure rate changes have been too much between water treatment plant and dead ends in distribution ... Systems that have big transmission line may have problem on changes of pressure in the distribution system. Because pressure rate changes have been too much between water treatment plant and dead ends in distribution system. This study is to analyze the effects pressure changes on the water quality in water distribution systems. It is located in south west of Ahwaz in IRAN. Ahwaz has five water treatment plants. In Ahwaz, two methods will be utilized. In the first method, samples will be taken from different locations in other to examine the quality of water in the distribution systems and the other method involves the use of simulation of models EPANET. Based on the EPANET model analysis of the water distribution system of Ahwaz as shown in result above the systems has large transmission line and exten- sive networks. So, the distance travelled and residence times have been causing to increase bacterial growth (HPC), chlorine consumption and hydraulic change (pressure) in water distribution system in Ahwaz. Pressure has a reversed relationship with bacterial growth (HPC) and Pressure has a direct relationship with residual chlorine. Pressure change has been causing to increase chlorine consumption more. So, Kw hasn’t any relationship with pressure and bacterial growth (HPC). The result of pressure changes among others can decrease in chlorine content and hydraulic factors, because the systems may be extensive and thus possess complex networks and hangs in quantity cause pressure of flow. Hence hydraulic changes (pressure) could affect of water quality in the water distribution system. 展开更多
关键词 Residual CHLORinE Bacterial Growth (HPC) pressure changeS WATER Quality Kw and WATER Distribution System
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