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Development and evaluation of a RT-RAA-combined CRISPR/Cas12a assay for the detection of African horse sickness virus
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作者 Yingzhi Zhang Lei Na +5 位作者 Kui Guo Jinhui Wang Zhe Hu Cheng Du Xuefeng Wang Xiaojun Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第12期4267-4271,共5页
African horse sickness(AHS)is an acute and fatal vectorborne infectious disease of equids,caused by the African horse sickness virus(AHSV).The World Organization for Animal Health(WOAH)has classified AHS as a notifiab... African horse sickness(AHS)is an acute and fatal vectorborne infectious disease of equids,caused by the African horse sickness virus(AHSV).The World Organization for Animal Health(WOAH)has classified AHS as a notifiable animal disease,and AHS has also been classified as a Class I animal infectious disease in China.AHS is mainly found in Africa,the Middle East and the Arabian Peninsula.China is currently recognized by the WOAH as an AHS-free zone. 展开更多
关键词 HAS HORSE sickness
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Effect of dissolved-oxygen on the flotation behavior of pyrite at high altitude area
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作者 Yan Miao Guangke Ye Guofan Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第10期2148-2158,共11页
With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been emphasized.There is a consensus that moderate oxidation of sulfide ore ... With the continuous development of mineral resources to high altitude areas,the study of sulfide ore flotation in unconventional systems has been emphasized.There is a consensus that moderate oxidation of sulfide ore is beneficial to flotation,but the specific suitable dissolved oxygen value is inconclusive,and there are few studies on sulfide ore flotation under low dissolved oxygen environment at high altitude.In this paper,we designed and assembled an atmosphere simulation flotation equipment to simulate the flotation of pyrite at high altitude by controlling the partial pressure of N_(2)/O_(2) and dissolved oxygen under atmospheric conditions.X-ray photoelectron spec-troscopy(XPS),atomic force microscope(AFM),Fourier transform infrared spectrometer(FT-IR),UV-vis spectrophotometer,zeta po-tential,and contact angle measurements were used to reveal the effects of surface oxidation and agent adsorption on pyrite at high altitude(4600 m dissolved oxygen(DO)=4.0 mg/L).The results of pure mineral flotation indicated that the high altitude and low dissolved oxy-gen environment is favorable for pyrite flotation.Contact angle measurements and XPS analysis showed that the high altitude atmosphere nslows down the oxidation of pyrite surface,facilitates S_(n)^(2-)/S^(0) production and enhances surface hydrophobicity.Electrochemical calcula-tions and zeta potential analysis showed that the influence of atmosphere on the form of pyrite adsorption is small,and the different atmo-spheric conditions are consistent with dixanthogen electrochemical adsorption,with lower Zeta potential under high altitude atmosphere and significant potential shift after sodium isobutyl xanthate(SIBX)adsorption.The results of FT-IR,UV-vis,and AFM analysis showed that SIBX adsorbed more on the surface of pyrite under high altitude atmosphere and adsorbed on the surface in a mesh structure com-posed of column/block.The results of the experimental study revealed the reasons for the easy flotation of sulfide ores at high altitude with less collector dosage,and confirmed that the combined DO-pH regulation is beneficial to achieve more efficient flotation of pyrite. 展开更多
关键词 high altitude DISSOLVED-OXYGEN PYRITE FLOTATION OXIDATION
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Soil Physico-Chemical Properties and Different Altitudes Affect Arbuscular Mycorrhizal Fungi Abundance and Colonization in Cacao Plantations of Cameroon
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作者 Franklin Tounkam Ketchiemo Beaulys Fotso +4 位作者 Astride Stéphanie Mouafi Djabou Victor Jos Eyamo Evina Japhet Youri Essambita Franck Maxime Ewane Tang Nicolas Niemenak 《American Journal of Plant Sciences》 CAS 2024年第2期57-82,共26页
This study aims to investigate the abundance of AMF according to soil properties and altitudes in different cacao plantations of Cameroon. Physico-chemical analyses were made on soil samples collected from three agro-... This study aims to investigate the abundance of AMF according to soil properties and altitudes in different cacao plantations of Cameroon. Physico-chemical analyses were made on soil samples collected from three agro-ecological zones. Soil samples were also used to evaluate directly the AMF abundance following the various altitudes and after trapping by sorghum plant. The results showed that soil properties, AMF spore abundances and colonization fluctuated significantly at different altitudes. The most represented texture was sandy loam. The bimodal zone presented a homogeneous texture (sandy loam) in all its localities. Cacao soil chemical characteristics showed that, the highest nitrogen rate (0.47%;p 0.05, Scott-Knott test) was recorded at Melong in a monomodal zone while Tonga in the Western highlands displayed the lowest rate (0.13%). Soil P concentration was significantly high in monomodal zones (Mbanga and Melong). Soil pH level indicated that the soil from Tonga in the Western highlands was neutral (pH = 6.67), and soils of other localities under study were acidic with the lowest (4.75) pH level recorded at Melong in a monomodal zone. In soil samples, the highest spore density (1.03 spores/g soil) was observed at Ntui in Bimodal zone, while the lowest spore density (0.26 spores/g soil) was observed at Bafang in the Western highlands. Root colonization showed that the sample from Bokito in a bimodal zone displayed the best frequency of mycorrhization (86.11%) while the sample from Bafang in the Western highlands recorded the lowest (27.11%). The PCA analysis highlighted that available phosphorus, pH and altitude all strongly correlated with AMF root colonization ability and can be used as a predictor of AMF colonization ability in cacao rhizosphere. 展开更多
关键词 Agroecological Zone altitude Variations Arbuscular Mycorrhizal Fungi Soil Properties Theobroma cacao
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Overview of radar detection methods for low altitude targets in marine environments
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作者 YANG Yong YANG Boyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期1-13,共13页
In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath scattering.The performance... In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath scattering.The performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments. 展开更多
关键词 RADAR sea clutter multipath scattering detection low altitude target
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The characteristics of negative corona discharge and radio interference at different altitudes based on coaxial wire-cylinder gap
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作者 何旺龄 魏宏宇 +6 位作者 张胤禄 刘永聪 刘云鹏 万保权 周阳 王延召 干喆渊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期77-85,共9页
The corona discharge from transmission lines in high-altitude areas is more severe than at lower altitudes. The radio interference caused thereby is a key factor to be considered when designing transmission lines. To ... The corona discharge from transmission lines in high-altitude areas is more severe than at lower altitudes. The radio interference caused thereby is a key factor to be considered when designing transmission lines. To study the influence of altitude on negative corona characteristics, an experimental platform comprising a movable small corona cage was established: experiments were conducted at four altitudes in the range of 1120-4320 m, and data on the corona current pulse and radio interference level of 0.8-mm diameter fine copper wire under different negative voltages were collected. The experimental results show that the average amplitude, repetition frequency and average current of the corona current pulse increase with increasing altitude. The dispersion of pulse amplitude increases with increase in altitude, while the randomness of the pulse interval decreases continuously. Taking the average current as an intermediate variable,the relationship between radio interference level and altitude is obtained. The result of this research has some significance for understanding the corona discharge characteristics of ultra-highvoltage lines. 展开更多
关键词 altitude negative corona corona current pulse radio interference level
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The cardiovascular system at high altitude:A bibliometric and visualization analysis
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作者 Mao-Lin Zhao Zhong-Jie Lu +6 位作者 Li Yang Sheng Ding Feng Gao Yuan-Zhang Liu Xue-Lin Yang Xia Li Si-Yi He 《World Journal of Cardiology》 2024年第4期199-214,共16页
BACKGROUND When exposed to high-altitude environments,the cardiovascular system undergoes various changes,the performance and mechanisms of which remain controversial.AIM To summarize the latest research advancements ... BACKGROUND When exposed to high-altitude environments,the cardiovascular system undergoes various changes,the performance and mechanisms of which remain controversial.AIM To summarize the latest research advancements and hot research points in the cardiovascular system at high altitude by conducting a bibliometric and visualization analysis.METHODS The literature was systematically retrieved and filtered using the Web of Science Core Collection of Science Citation Index Expanded.A visualization analysis of the identified publications was conducted employing CiteSpace and VOSviewer.RESULTS A total of 1674 publications were included in the study,with an observed annual increase in the number of publications spanning from 1990 to 2022.The United States of America emerged as the predominant contributor,while Universidad Peruana Cayetano Heredia stood out as the institution with the highest publication output.Notably,Jean-Paul Richalet demonstrated the highest productivity among researchers focusing on the cardiovascular system at high altitude.Furthermore,Peter Bärtsch emerged as the author with the highest number of cited articles.Keyword analysis identified hypoxia,exercise,acclimatization,acute and chronic mountain sickness,pulmonary hypertension,metabolism,and echocardiography as the primary research hot research points and emerging directions in the study of the cardiovascular system at high altitude.CONCLUSION Over the past 32 years,research on the cardiovascular system in high-altitude regions has been steadily increasing.Future research in this field may focus on areas such as hypoxia adaptation,metabolism,and cardiopulmonary exercise.Strengthening interdisciplinary and multi-team collaborations will facilitate further exploration of the pathophysiological mechanisms underlying cardiovascular changes in high-altitude environments and provide a theoretical basis for standardized disease diagnosis and treatment. 展开更多
关键词 Cardiovascular system High altitude HYPOXIA Bibliometric analysis VISUALIZATION
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Modification of streamer-to-leader transition model based on radial thermal expansion in the sphere-plane gap discharge at high altitude
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作者 耿江海 林果 +3 位作者 王平 丁玉剑 丁杨 俞华 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期42-49,共8页
Historically,streamer-to-leader transition studies mainly focused on the rod-plane gap and low altitude analysis,with limited attention paid to the sphere-plane gap at high altitude analysis.In this work,sphere-plane ... Historically,streamer-to-leader transition studies mainly focused on the rod-plane gap and low altitude analysis,with limited attention paid to the sphere-plane gap at high altitude analysis.In this work,sphere-plane gap discharge tests were carried out under the gap distance of 5 m at the Qinghai Ultra High Voltage(UHV)test base at an altitude of 2200 m.The experiments measured the physical parameters such as the discharge current,electric field intensity and instantaneous optical power.The duration of the dark period and the critical charge of streamer-toleader transition were obtained at high altitude.Based on radial thermal expansion of the streamer stem,we established a modified streamer-to-leader transition model of the sphere-plane gap discharge at high altitude,and calculated the stem temperature,stem radii and the duration of streamer-to-leader transition.Compared with the measured duration of sphere-plane electrode discharge at an altitude of 2200 m,the error rate of the modified model was 0.94%,while the classical model was 6.97%,demonstrating the effectiveness of the modified model.From the comparisons and analysis,several suggestions are proposed to improve the numerical model for further quantitative investigations of the leader inception. 展开更多
关键词 streamer-to-leader transition model high altitude streamer stem convective diffusion radial thermal expansion
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Predicting Acute Mountain Sickness Using Regional Sea-Level Cerebral Blood Flow
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作者 Hao Zhang Jie Feng +2 位作者 Shiyu Zhang Wenjia Liu Lin Ma 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期887-896,共10页
Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy v... Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea level.The CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS groups.Statistical analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)curves.Results The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(P<0.05).In men,the cortical CBF values in the bilateral ACA,PCA,PICA,and right MCA were higher in patients with AMS than in those without.Cortical CBF in the right PCA best predicted AMS(AUC=0.818).In women,the LI of CBF in the ACA was different between the AMS and non-AMS groups and predicted AMS with an AUC of 0.753.Conclusion Although the mechanism and prediction of AMS are quite complicated,higher cortical CBF at sea level,especially the CBF of the posterior circulatory system,may be used for prediction in male volunteers using non-invasive 3D-pCASL. 展开更多
关键词 Acute mountain sickness High-altitude headache Cerebral blood flow Arterial spin labeling Magnetic resonance imaging
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Physicochemical composition and climate response of surface sediments at different altitudes in Motuo on the southern slope of the Himalayas
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作者 XIE Mengping SONG Yougui +2 位作者 LAN Minwen ZHANG Mingyu HAN Yixiao 《地球环境学报》 CSCD 2024年第4期624-640,共17页
Background,aim,and scope Certain physicochemical indexes of topsoil are closely related to climatic factors including temperature,and precipitation.Understanding the relationship between modern topsoil properties and ... Background,aim,and scope Certain physicochemical indexes of topsoil are closely related to climatic factors including temperature,and precipitation.Understanding the relationship between modern topsoil properties and climatic factors is essential for quantitative paleoclimate reconstruction.Motuo located in the eastern Himalayas,exhibits a significant elevation gradient of over 7000 m from Nnamjagbarwa Peak(7782 m a.s.l.)to the Baxika(150 m a.s.l.).This region features a complete vertical zonation of vegetation,from alpine meadow to tropical forest,presenting an ideal place to investigate the relationships among vegetation,soil and climate conditions across altitudinal gradients.This study aims to explore the vertical variations in the physicochemical composition of topsoil and its relationship with temperature and precipitation.Materials and methods Twenty-seven topsoil samples were collected at 100 m intervals from 800 m to 3600 m a.s.l.along the southern slope of the Himalayas.Grain size,magnetic susceptibility and geochemical elements were measured to discuss the vertical variation characteristics of topsoil composition and their correlation with climatic factors.Results(1)The grain size of topsoil at different altitudes in Motuo is mainly composed of sand accounting for an averaged 53.2%,followed by silt and clay.(2)In the mixed forest zone,frequency dependent magnetic susceptibility(χfd%)shows a clear relationship with altitude,and clay is positively correlated with both altitude and climatic factors.(3)The oxides of topsoil in this area mainly consist of SiO_(2),Al_(2)O_(3) and Fe_(2)O_(3),followed by MgO,CaO,Na_(2)O and K_(2)O,with slight variations in the primary components at different altitudes.The sensitivity of elements to climate varies across different altitudes and vegetation zone,likely due to the region’s complex topography and vegetation.(4)Physical and biological weathering dominates in the broad-leaved forest zone of Motuo,while chemical weathering is more prominent in the coniferous forest zone,with the mixed forest zone falling in between.Discussion The formation of topsoil across the three vegetation zones is influenced by various factors,including parent material,vegetation,and climate.In the broad-leaved forest zone,physical weathering(precipitation,root wedging etc.)and pedogenesis dominate,resulting in finer grain size.The χ_(fd)% increases with altitude likely due to the high temperature and abundant precipitation in this zone,which facilitate the transformation of strong magnetic miners into weaker ones,particularly when the soil is oversaturated.Zirconium(Zr),primarily found in zircon,is depleted at lower altitudes by strong current erosion.Barium(Ba)is similarly reduced at low altitudes in this zone.In mixed forest zone,clay content is the lowest,indicating weaker physical weathering conditions than broad-leaved forest zone.The coarser grain size may result from the combined effects of topography and vegetation coverage.Magnetic susceptibility and organic matter show a positive correlation with altitude.Zr concentration is higher than that in the broad-leaved forest zone,likely resulting from decreased precipitation.In the coniferous zone,the clay content shows considerable fluctuations,with grain size generally becoming finer as altitude increases.This trend may be explained by intensified soil disintegration from seasonal freeze-thaw cycles.The χ_(fd)% values lack a clear trend or pattern,possibly due to soil erosion causing the migration of magnetic minerals or insufficient iron precipitation,which reduces the concentration of magnetic minerals in the soil.Additionally,a positive correlation is observed between altitude and organic matter content,with higher altitudes associated with greater organic matter accumulation.This may be attributed to lower microbial activity in colder conditions,which slows the decomposition and transformation of organic matter.Conclusions The variations in grain size,magnetic susceptibility,and geochemical elements differ across altitudes and vegetation zones,closely connected to the complex interplay of terrain,vegetation,and climate in Motuo.In the mixed forest,altitude has a significant impact onχfd%,and the clay component is particularly sensitive to changes in altitude,mean annual temperature,and precipitation.Zr shows a strong correlation with altitude and climate factors,making it a valuable indicator for assessing changes in atmospheric precipitation within specific altitude ranges.Recommendations and perspectives This study enhances our understanding of the relationships between the physicochemical properties of topsoil and climate conditions,offering valuable insights for paleoclimate reconstruction in Motuo. 展开更多
关键词 southern slope of the Himalayas MOTUO TOPSOIL altitude difference vegetation zone physicochemical indexes
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China Seeks to Grab Opportunities Brought about by the Low-Altitude Economy
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作者 Lily Wang 《China's Foreign Trade》 2024年第3期50-51,共2页
Since the inclusion of the low-altitude economy in the government work report during the National People’s Congress and the Chinese People’s Political Consultative Conference in March,many cities have sought to ente... Since the inclusion of the low-altitude economy in the government work report during the National People’s Congress and the Chinese People’s Political Consultative Conference in March,many cities have sought to enter this area first to seize the benefits of the low-altitude economy.According to incomplete statistics,17 provinces(municipalities,autonomous regions)in China have currently written the low-altitude economy into their 2024 government work report.In addition,cities such as Shenzhen,Guangzhou,Chengdu,Suzhou,Zhuhai,and Ganzhou have also included the low-altitude economy in their government work reports.More than 20 provincial and municipal governments,represented by Shenzhen,Hefei,Guangzhou and Chengdu,have introduced also policies to support the development of the low-altitude economy and its business ecosystem. 展开更多
关键词 altitude INCOMPLETE autonomous
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Differential pressure difference based altitude control of a stratospheric satellite
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作者 陈丽 WANG Xiaoliang 《High Technology Letters》 EI CAS 2024年第1期1-12,共12页
An autonomous altitude adjustment system for a stratospheric satellite(StratoSat)platform is proposed.This platform consists of a helium balloon,a ballonet,and a two-way blower.The helium balloon generates lift to bal... An autonomous altitude adjustment system for a stratospheric satellite(StratoSat)platform is proposed.This platform consists of a helium balloon,a ballonet,and a two-way blower.The helium balloon generates lift to balance the platform gravity.The two-way blower inflates and deflates the ballonet to regulate the buoyancy.Altitude adjustment is achieved by tracking the differential pressure difference(DPD),and a threshold switching strategy is used to achieve blower flow control.The vertical acceleration regulation ability is decided not only by the blower flow rate,but also by the designed margin of pressure difference(MPD).Pressure difference is a slow-varying variable compared with altitude,and it is adopted as the control variable.The response speed of the actuator to disturbance can be delayed,and the overshoot caused by the large inertia of the platform is inhibited.This method can maintain a high tracking accuracy and reduce the complexity of model calculation,thus improving the robustness of controller design. 展开更多
关键词 stratospheric satellite(StratoSat) differential pressure difference(DPD) altitude adjustment threshold switching strategy margin of pressure difference(MPD)
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Study on Skin Care Efficacy of the Active Ingredients in Camellia Japonica Flowers at High and Low Altitudes
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作者 Cao Yimiao Gao Hongqi +1 位作者 Gao Cong Deng Quanzhi 《China Detergent & Cosmetics》 CAS 2024年第1期76-80,共5页
The active ingredients of Camellia japonica flowers(CJF)at high and low altitudes,as well as their skin care efficacy were compared.The dried red CJF at high and low altitudes were ultrasonically extracted with 70%eth... The active ingredients of Camellia japonica flowers(CJF)at high and low altitudes,as well as their skin care efficacy were compared.The dried red CJF at high and low altitudes were ultrasonically extracted with 70%ethanol,and these extracts were concentrated and then diluted to a constant volume.The content of total flavonoids,total polyphenols and total proteins was tested and analyzed.In addition,DPPH free radical scavenging,inhibition of the formation of advanced glycation end products,and inhibitory activity against elastase was measured to compare their skin care efficacy in anti-oxidation,anti-glycation,anti-wrinkling and firming.The results showed that,based on the dry weight of CJF,the content of total flavonoids and total proteins of the CJF at high altitude was approximately 1.5 times of the CJF at low altitude,while the content of total polyphenols was approximately 2.4 times that of the CJF at low altitude.The skin care efficacy of CJF at high altitude was significantly better than that of the CJF at low altitude.This work could provide theoretical basis for the selection and application of Camellia japonica flowers in the field of cosmetics. 展开更多
关键词 camellia japonica flowers at high and low altitudes active ingredients skin care efficacy
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Early Warning of Acute Altitude Sickness by Physiological Variables and Noninvasive Cardiovascular Indicators 被引量:8
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作者 Zongbin Li Chunwei Liu +5 位作者 Jun Guo Yajun Shi Yang Li Jinli Wang Jing Wang Yundai Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2020年第1期13-19,共7页
Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude.Methods One hundred and six Han nation... Objective To examine if the variations at sea level would be able to predict subsequent susceptibility to acute altitude sickness in subjects upon a rapid ascent to high altitude.Methods One hundred and six Han nationality male individuals were recruited to this research.Dynamic electrocardiogram,treadmill exercise test,echocardiography,routine blood examination and biochemical analysis were performed when subjects at sea level and entering the plateau respectively.Then multiple regression analysis was performed to construct a multiple linear regression equation using the Lake Louise Score as dependent variable to predict the risk factors at sea level related to acute mountain sickness(AMS).Results Approximately 49.05%of the individuals developed AMS.The tricuspid annular plane systolic excursion(22.0+2.66 vs.23.2+3.19 mm,t=l.998,P=0.048)was significantly lower in the AMS group at sea level,while count of eosinophil[(0.264+0.393)×109/L vs.(0.126+0.084)×109/L,t=-2.040,P—0.045],percentage of diflerences exceeding 50 ms between adjacent normal number of intervals(PNN50,9.66%±5.40%vs.6.98%±5.66%,t=-2.229,P=0.028)and heart rate variability triangle index(57.1+16.1 vs.50.6+12.7,t=-2.271,P=0.025)were significantly higher.After acute exposure to high altitude,C-reactive protein(0.098+0.103 vs.0.062+0.045 g/L,t=-2.132,P=0.037),aspartate aminotransferase(19.7+6.7275.17,3±3.95 U/L,t=-2.231,P=0.028)and creatinine(85.1±12.9 vs.77.7±11.2 mmol/L,t=3.162,P=0.002)were significantly higher in the AMS group,while alkaline phosphatase(71.7+18.2 vs.80.6+20.2 U/L,t=2.389,P=0.019),standard deviation of normal-to-normal RR intervals(126.5+35.9 vs.143.3+36.4 ms,t—2.320,P—0.022),ejection time(276.9+50.8 vs.313.8+48.9 ms,t—3.641,P—0.001)and heart rate variability triangle index(37.1+12.9 vs.41.9+11.1,t=2.O2O,P=0.047)were significantly lower.Using the Lake Louise Score as the dependent variable,prediction equation were established to estimate AMS:Lake Louise Score=3.783+0.281Xeosinophil-0.219Xalkaline phosphatase+O.O32XPNN50.Conclusions We elucidated the differences of pl^siological variables as well as noninvasive cardiovascular indicators for subjects after high altitude exposure compared with those at sea level.We also created an acute high altitude reaction early warning equation based on the physiological variables and noninvasive cardiovascular indicators at sea level. 展开更多
关键词 ACUTE altitude sickness PHYSIOLOGICAL VARIABLES NONINVASIVE CARDIOVASCULAR indicators ACUTE high altitude exposure early warning
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Association between physiological responses after exercise at low altitude and acute mountain sickness upon ascent is sex-dependent 被引量:3
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作者 Yang Shen Yuan-Qi Yang +11 位作者 Chuan Liu Jie Yang Ji-Hang Zhang Jun Jin Hu Tan Fang-Zheng-Yuan Yuan Jing-Bin Ke Chun-Yan He Lai-Ping Zhang Chen Zhang Jie Yu Lan Huang 《Military Medical Research》 SCIE CSCD 2021年第2期174-182,共9页
Background:Acute mountain sickness(AMS)is the mildest form of acute altitude illnesses,and consists of nonspecific symptoms when unacclimatized persons ascend to elevation of≥2500 m.Risk factors of AMS include:the al... Background:Acute mountain sickness(AMS)is the mildest form of acute altitude illnesses,and consists of nonspecific symptoms when unacclimatized persons ascend to elevation of≥2500 m.Risk factors of AMS include:the altitude,individual susceptibility,ascending rate and degree of pre-acclimatization.In the current study,we examined whether physiological response at low altitude could predict the development of AMS.Methods:A total of 111 healthy adult healthy volunteers participated in this trial;and 99(67 men and 32 women)completed the entire study protocol.Subjects were asked to complete a 9-min exercise program using a mechanically braked bicycle ergometer at low altitude(500 m).Heart rate,blood pressure(BP)and pulse oxygen saturation(SpO2)were recorded prior to and during the last minute of exercise.The ascent from 500 m to 4100 m was completed in 2 days.AMS was defined as≥3 points in a 4-item Lake Louise Score,with at least one point from headache wat 6–8 h after the ascent.Results:Among the 99 assessable subjects,47(23 men and 24 women)developed AMS at 4100 m.In comparison to the subjects without AMS,those who developed AMS had lower proportion of men(48.9%vs.84.6%,P<0.001),height(168.4±5.9 cm vs.171.3±6.1 cm,P=0.019),weight(62.0±10.0 kg vs.66.7±8.6 kg,P=0.014)and proportion of smokers(23.4%vs.51.9%,P=0.004).Multivariate regression analysis revealed the following independent risks for AMS:female sex(odds ratio(OR)=6.32,P<0.001),SpO2 change upon exercise at low altitude(OR=0.63,P=0.002)and systolic BP change after the ascent(OR=0.96,P=0.029).Women had larger reduction in SpO2 after the ascent,higher AMS percentage and absolute AMS score.Larger reduction of SpO2 after exercise was associated with both AMS incidence(P=0.001)and AMS score(P<0.001)in men but not in women.Conclusions:Larger SpO2 reduction after exercise at low altitude was an independent risk for AMS upon ascent.Such an association was more robust in men than in women.Trial registration:Chinese Clinical Trial Registration,ChiCTR1900025728.Registered 6 September 2019. 展开更多
关键词 High altitude Exercise testing Sex differences Acute mountain sickness Individual susceptibility
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Ataxia,acute mountain sickness,and high altitude cerebral edema 被引量:3
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作者 Wu Tianyi Ma Siqing +1 位作者 Bian Huiping Zhang Minming 《Engineering Sciences》 EI 2013年第2期38-46,共9页
Previous investigations suggest that ataxia is common and often one of the most reliable warning signs of high altitude cerebral edema(HACE). The aim of this study was to investigate the diagnostic role of ataxia in a... Previous investigations suggest that ataxia is common and often one of the most reliable warning signs of high altitude cerebral edema(HACE). The aim of this study was to investigate the diagnostic role of ataxia in acute mountain sickness(AMS)and HACE among mountain rescuers on the quake areas,and in approaching the relation between AMS and HACE. After the earthquake on April 14,2010,approximately 24 080 lowland rescuers were rapidly transported from sea level or lowlands to the mountainous rescue sites at 3 750 ~ 4 568 m,and extremely hardly worked for an emergency treatment after arrival. Assessments of acute altitude illness on the quake areas were using the Lake Louise Scoring System. 73 % of the rescuers were found to be developed AMS. The incidence of high altitude pulmonary edema(HAPE)and HACE was 0.73 % and 0.26 %,respectively,on the second to third day at altitude. Ataxia sign was measured by simple tests of coordination including a modified Romberg test. The clinical features of 62 patients with HACE were analyzed. It was found that the most frequent,serious neurological symptoms and signs were altered mental status(50/62,80.6 %)and truncal ataxia(47/62,75.8 %). Mental status change was rated slightly higher than ataxia,but ataxia occurred earlier than mental status change and other symptoms. The earliest sign of ataxia was a vague unsteadiness of gait,which may be present alone in association with or without AMS. Advanced ataxia was correlated with the AMS scores,but mild ataxia did not correlate with AMS scores at altitudes of 3 750~4 568 m. Of them,14 patients were further examined by computerized tomographic scanning of the brain and cerebral magnetic resonance imagines were examined in another 15 cases. These imaging studies indicated that the presence of the cerebral edema was in 97 % of cases who were clinically diagnosed as HACE(28/29). Ataxia seems to be a reliable sign of advanced AMS or HACE,so does altered mental status. 展开更多
关键词 Yushu Earthquake ATAXIA acute mountain sickness high altitude cerebral edema Lake Louise Scoring System
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The denitrogenation by breathing oxygen-rich gas to prevent altitude decompression sickness 被引量:3
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作者 Hua-jun XIAO Xiao-peng LIU +2 位作者 Bin ZANG Gui-you WANG Zhao GU 《中国应用生理学杂志》 CAS CSCD 2012年第6期568-571,共4页
Objective While the technology of the molecular sieve oxygen generation system(MSOGS) onboard was used,pilots could not breathe pure oxygen to eliminate nitrogen during a high altitude flight.There is no report whethe... Objective While the technology of the molecular sieve oxygen generation system(MSOGS) onboard was used,pilots could not breathe pure oxygen to eliminate nitrogen during a high altitude flight.There is no report whether it is a threat to altitude decompression sickness(ADS) or not in that condition.This experiment was intended to observe the effects of breathing different oxygen-rich gases of MSOGS on denitrogenation,so that we could make the medical physiological requirements for MSOGS on-board and provide experimental basis for aeromedical supply.Method Eight healthy males were breathed oxygenrich gases(60%,70%,80%,90%and 99.6%) in turn for 60 min,and the concentration of nitrogen,oxygen,carbon dioxide and argon at the end of expiration interval in the oxygen mask were continuously measured by a flight mass spectrometer through the oxygen mask.According to the variety of the denitrogenation rate by breathing different oxygen-rich gases,its change law was analyzed.Results There were significant differences(P<0.05) about denitrogenation rate in different oxygen-rich gases due to different oxygen concentration and breathing time.The denitrogenation rate of pure oxygen was higher than that of the others.It was indicated that the concentration of nitrogen in lung would decrease along with the increase in oxygen concentration of oxygen-rich gases,and the nitrogen concentration in the lung almost decreased by 50% or even more if people were breathed 60%~90% oxygen-rich gas longer than 60 s.Conclusion The man-made respiration environment of low nitrogen can be provided by breathing oxygen-rich gases,although the denitrogenation velocity of breathing oxygen-rich gases is lower than that of breathing pure oxygen.So it can be used as a measure to eliminate and lower the nitrogen in the body to prevent from ADS. 展开更多
关键词 脱氮率 呼吸 气体 富氧 减压 高空 氧气面罩 时间间隔
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Rong Shuan Jiao Nang in the treatment of acute mountain sickness and high altitude myocardial ischemic syndrome in Yushu 被引量:1
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作者 Wu Tianyi Du Yu +2 位作者 Li Wenxiang Cairen-Jiangcuo Li Ye 《Engineering Sciences》 EI 2013年第2期76-81,共6页
To evaluate the therapeutic effects of Rong Shuan Jiao Nang (RSJN) on treatment of acute mountain sickness (AMS) and high altitude myocardial ischemic syndrome in workers in Yushu, three groups were studied: grou... To evaluate the therapeutic effects of Rong Shuan Jiao Nang (RSJN) on treatment of acute mountain sickness (AMS) and high altitude myocardial ischemic syndrome in workers in Yushu, three groups were studied: group A (60 patients with AMS, given RSJN), group B (15 patients with altitude myocardial ischemic syndrome, given RSJN), and group C (control, without drugs). All studied subjects were lowland workers who were first time entry to Yushu for work at an altitude of 4 250 m. During the course of treatment, a routing physical examina- tion was performed, AMS Lake Louise Scores were estimated, arterial oxygen saturation (SaO2), electrocardiography and hemoglobin concentration were measured before and after using RSJN for 10 days. In group A, the effective rate was 68 %, symptomatic improvement in 54 cases (90 %) within 5 days. In group B, the effective rate was 93 %, episodes of angina pectoris stopped in 12 patients within 3 - 7 days, one lasted 8 days. After treatment, the level of SaO2 increased 15.5 %, 21.8 % and 5.6 % in group A, group B and group C, respectively. RSJN tak- en at the start of the arrival at Yushu can decrease AMS scores and facilitate cure. If taken after the illness has begun, RSJN may help lessen symptoms, especially effectively improved angina pectoris of the high altitude myocardial ischemic syndrome. Symptoms usually subside after 3 - 8 days. RSJN should be continually used lbr at least 7 days after ascent. 展开更多
关键词 Rong Shuan Jiao Nang THERAPY acute mountain sickness high altitude myocardial ischemic syndrome
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SNPs and TFBS Associated with High Altitude Sickness
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作者 Norman E. Buroker Xuehan Ning +6 位作者 Zhaonian Zhou Kui Li Weijun Cen Xiufeng Wu Weizhong Zhu C. Ronald Scott Shihan Chen 《Open Journal of Blood Diseases》 2013年第3期85-93,共9页
The rSNPs for the genes AKT3 (rs4590656), EGLN1 (rs480902), eNOS3 (rs1007311), and VEGFA (rs699947, rs13207311, rs1570360, rs2010963) have been significantly associated with the physiological parameters in high altitu... The rSNPs for the genes AKT3 (rs4590656), EGLN1 (rs480902), eNOS3 (rs1007311), and VEGFA (rs699947, rs13207311, rs1570360, rs2010963) have been significantly associated with the physiological parameters in high altitude sickness Han or Tibetan Chinese patients at the Qinghai-Tibetan plateau. The alleles of each rSNP have been found to create unique transcriptional factor binding sites for transcription factors that affect the process of hypoxia gene expression in this high altitude hypoxia environment. 展开更多
关键词 HIGH altitude sickness rSNPs TFBS
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Research on the distribution characteristics of explosive shock waves at different altitudes 被引量:6
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作者 Liang-quan Wang De-ren Kong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第6期340-348,共9页
There are great differences in the distribution characteristics of shock waves produced by ammunition explosions at different altitudes.At present,there are many studies on plain explosion shock waves,but there are fe... There are great differences in the distribution characteristics of shock waves produced by ammunition explosions at different altitudes.At present,there are many studies on plain explosion shock waves,but there are few studies on the distribution characteristics of plateau explosion shock waves,and there is still a lack of complete analysis and evaluation methods.This paper compares and analyzes shock wave overpressure data at different altitudes,obtains the attenuation effect of different altitudes on the shock wave propagation process and proposes a calculation formula for shock wave overpressure considering the effect of altitude.The data analysis results show that at the same TNT equivalent and the same distance from the measuring point,the shock wave overpressure at high altitude is lower than that at low altitude.With the increase in the explosion center distance of the measuring point,the peak attenuation rate of the shock wave overpressure at high altitudes is smaller than that at low altitudes,and the peak attenuation rate of the shock wave overpressure at high altitudes gradually intensifies with increasing proportional distance.The average error between the shock wave overpressure and measured shock wave overpressure in a high-altitude environment obtained by using the above calculation formula is 11.1389%.Therefore,this method can effectively predict explosion shock wave overpressure in plateau environments and provides an effective calculation method for practical engineering tests. 展开更多
关键词 Shock wave overpressure calculation Pressure attenuation law altitude correction factor Engineering numerical model
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Traditional Chinese medicine for acute mountain sickness prevention: A systematic review and meta-analysis of randomized controlled trials 被引量:1
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作者 Hui Luo Xing Liao +1 位作者 Qiaoling Tang Qian Wang 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第1期73-82,共10页
Objective: To evaluate the efficacy of traditional Chinese medicine(TCM) for preventing acute mountain sickness(AMS).Methods: We included randomized controlled trials(RCTs) which evalueded the effect of TCM for preven... Objective: To evaluate the efficacy of traditional Chinese medicine(TCM) for preventing acute mountain sickness(AMS).Methods: We included randomized controlled trials(RCTs) which evalueded the effect of TCM for preventing AMS, compared with a placebo, no treatment or acetazolamide. The literature was searched in 6major databases. RevMan 5.4 software was used for the meta-analysis. The relative risk for discrete variables and the mean difference for continuous variables with 95% confidence intervals(CIs) were applied to express the effect size. The risk of bias in the included studies was evaluated using the Cochrane risk assessment tool 2.0(RoB 2.0), and the evidence certainty was assessed using the Grading of Recommendations Assessment and the Development and Evaluation(GRADE) approach.Results: Twenty RCTs involving 3015 participants and 16 TCM patent drugs were included. The overall risk of bias in the majority of studies(15/20) was of some concerns. In terms of the AMS incidence,Rhodiola rosea(R. rosea, Hong Jing Tian) and Ginkgo biloba(G. biloba, Yin Xing Ye) were equivalent to the placebo/no treatment [RR(95% CI): 0.66(0.43-1.01), 0.82(0.63-1.06), respectively]. The AMS incidence in the G. biloba group was higher than that in the acetazolamide group [RR(95% CI): 2.92(1.69-5.06)]. In terms of improving the AMS symptom score on days 1 and 3 in the plateau, R. rosea and G. biloba were superior to the placebo or no treatment [MD(95% CI):-0.98(-1.71,-0.25),-2.05(-3.14,-0.95), respectively]. The other 14 Chinese patent medicines were evaluated in a single trial, and the majority of the results were negative. The subgroup analysis showed that the effect of R. rosea was related to the intervention time, way of ascending, and altitude.Conclusion: R. rosea and G. biloba were effective in improving AMS symptoms but had no effect in reducing the AMS incidence. There was insufficient evidence to support the use of other TCM patent drugs to prevent AMS. More randomized double-blind placebo-controlled trials are warranted to evaluate and screen effective Chinese patent medicines for AMS prevention. 展开更多
关键词 Acute mountain sickness PREVENTION Traditional Chinese medicine Rhodiola rosea Ginkgo biloba Randomized controlled trial Systematic review
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