Populations living at high altitudes （HAs）, particularly in the Peruvian Andes, are characterized by a mixture of subjects with erythrocytosis （16 g dl-1〈haemoglobin （Hb）≤21 gdl-1） and others with excessive er...Populations living at high altitudes （HAs）, particularly in the Peruvian Andes, are characterized by a mixture of subjects with erythrocytosis （16 g dl-1〈haemoglobin （Hb）≤21 gdl-1） and others with excessive erythrocytosis （EE） （Hb〉21 g dl-1）. Elevated haemoglobin values （EE） are associated with chronic mountain sickness, a condition reflecting the lack of adaptation to HA. According to current data, native men from regions of HA are not adequately adapted to live at such altitudes if they have elevated serum testosterone levels. This seems to be due to an increased conversion of dehydroepiandrosterone sulphate （DH EAS） to testosterone. Men with erythrocytosis at HAs show higher serum androstenedione levels and a lower testosterone/androstenedione ratio than men with EE, suggesting reduced 17beta-hydroxysteroid dehydrogenase （17beta-HSD） activity. Lower 17beta-HSD activity via A4-steroid production in men with erythrocytosis at HA may protect against elevated serum testosterone levels, thus preventing EE. The higher conversion of DHEAS to testosterone in subjects with EE indicates increased 17beta-HSD activity via the A5-pathway. Currently, there are various situations in which people live （human biodiversity） with low or high haemoglobin levels at HA. Antiquity could be an important adaptation component for life at HA, and testosterone seems to participate in this process.展开更多
Background:This study aimed to illustrate the prevalence of CHD by screening children in extremely high-altitudeareas(over 4000 m to even 5000 m above sea level)and explore an aid model for early diagnosis and treatme...Background:This study aimed to illustrate the prevalence of CHD by screening children in extremely high-altitudeareas(over 4000 m to even 5000 m above sea level)and explore an aid model for early diagnosis and treatmentfor the Tibetan population.Methods:A total of 2242 students from different schools in Ngamring County,Xigaze City,Tibet from September 2019 to September 2020 were selected for screening.The students were examinedthrough the inquiry of their current medical history and family history,cardiac auscultation and a physicalexamination,in order to screen out the suspected cases of CHD,and then the suspected cases were confirmed bycardiac color ultrasound examinations.After that,positive patients were be transferred to Shandong Province forfree treatment.Results:The prevalence of CHD among children in Ngamring County was 3.70%(83 cases),which is the highest incidence rate ever reported.The most common type of CHD was patent ductus arteriosus(PDA),accounting for 55.42%of the total number of cases screened,followed by atrial septal defect(ASD)andventricular septal defect(VSD),accounting for 28.92%and 12.05%,respectively.The prevalence of CHD in childrenat high altitude was significantly higher than that in children at low altitude.The children with CHD weretransferred to Shandong Province for surgery,the operations were successful and their recoveries went well.Conclusions:The results show that high altitude is closely related to the prevalence of CHD,and the incidencein Ngamring County is much higher than that in previous reports.展开更多
Maize(Zea mays ssp.mays)was domesticated approximately 9,000 years ago from Zea mays ssp.parviglumis,a lowland teosinte native to southwestern Mexico(Matsuoka et al.,2002).From the tropical origin,maize has spread int...Maize(Zea mays ssp.mays)was domesticated approximately 9,000 years ago from Zea mays ssp.parviglumis,a lowland teosinte native to southwestern Mexico(Matsuoka et al.,2002).From the tropical origin,maize has spread into a wide range of temperate regions with high latitudes and altitudes.Flowering time is a critical trait determining plant local adaptation.Several flowering time genes contributing to maize latitudinal adaptation have been identified(Yang et al.,2013;Guo et al.,2018;Huang et al.,2018;Liang et al.,2019;Wu et al.,2023).In contrast,the genetic mechanisms enabling maize adaptation to high-altitude environments remain poorly understood.展开更多
BACKGROUND Due to the dry and cold climate,the obvious temperature difference between day and night,and the low oxygen content of the air in the plateau area,people are prone to upper respiratory tract diseases,and of...BACKGROUND Due to the dry and cold climate,the obvious temperature difference between day and night,and the low oxygen content of the air in the plateau area,people are prone to upper respiratory tract diseases,and often the condition is prolonged,and the patients are prone to anxiety and uneasiness,which may be related to the harshness of the plateau environment,somatic discomfort due to the lack of oxygen,anxiety about the disease,and other factors.AIM To investigate the effects of cognitive behavioral therapy(CBT)on anxiety,sleep disorders,and hypoxia tolerance in patients with high-altitude respiratory diseases.METHODS A total of 2337 patients with high-altitude-related respiratory diseases treated at our hospital between November 2023 and January 2024 were selected as the study subjects.The subjects’pre-high-altitude residential altitude was approximately 1700 meters.They were divided into two groups.Both groups were given symptomatic treatment,and the control group implemented conventional nursing intervention,while the research group simultaneously conducted CBT intervention;assessed the degree of health knowledge of the two groups,and applied the Hamilton Anxiety Scale and the Pittsburgh Sleep Quality Index to assess the anxiety and sleep quality of the patients before and after the intervention,respectively.It also observed the length and efficiency of sleep,and detected the level of serum hypoxia inducible factor-1α,erythropoietin(EPO)and clinical intervention before and after intervention.EPO levels,and investigated satisfaction with the clinical intervention.RESULTS The rate of excellent health knowledge in the intervention group was 93.64%,which was higher than that in the control group(74.23%;P<0.05).Before the intervention,there was no significant difference in Hamilton Anxiety Scale and Pittsburgh Sleep Quality Index scores between the two groups(P>0.05),and after the intervention,the scores of the study group were significantly lower than those of the control group(P<0.05).There was no significant difference in sleep duration and sleep efficiency between the groups before the intervention(P>0.05),and after the intervention,the scores of the study group were significantly larger than those of the control group(P<0.05).There was no significant difference in serum hypoxia inducible factor-1αand EPO between the two groups before intervention(P>0.05),and both research groups were significantly lower than the control group after intervention(P<0.05).According to the questionnaire survey,the intervention satisfaction of the study group was 95.53%,which was higher than that of the control group(80.14%;P<0.05).CONCLUSION The CBT intervention in the treatment of patients with high-altitude-related respiratory diseases helps improve patients'health knowledge,relieve anxiety,improve sleep quality and hypoxia tolerance,and improve nursing satisfaction.展开更多
The hypoxic environment at high altitudes causes various sleep disorders.Diffuse oxygen enrichment is an effective way to alleviate sleep disorders and improve the built environment in high altitude areas.In this stud...The hypoxic environment at high altitudes causes various sleep disorders.Diffuse oxygen enrichment is an effective way to alleviate sleep disorders and improve the built environment in high altitude areas.In this study,a novel point source local diffuse oxygen supply method was proposed to improve the sleeping oxygen environment.The oxygen supply performance was investigated by the computational fluid dynamics(CFD)method including the oxygen concentration and air velocity distributions.A sleeping experiment was conducted on the plateau to validate the CFD model.The occupied zone including the inhalation zone and the active zone was defined.The results showed that the oxygen concentration showed a rapid rise,then decreased slowly,and finally tended to be stable.The oxygen concentration after stabilization was remarkably influenced by indoor ventilation rate.The sleeping environment’s improvement was examined considering the oxygen enrichment efficiency,uniformity,stability and human comfort demand.The optimal strategies were recommended with a ventilation rate of 1 air change per hour,supplied oxygen concentration of 90%;and jet distance of 0.50 m.The study contributes to improving the oxygen environment and human sleep quality in an effective and energy-saving approach to the sustainable development of buildings in high altitude areas.展开更多
The solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort.It can bring favorable passive solar heating and can result in undesired overheating(even in winter).Thi...The solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort.It can bring favorable passive solar heating and can result in undesired overheating(even in winter).This problem becomes more critical for high altitudes with high intensity of solar irradiance,while received limited attention.In this study,we explored the specific overheating and rising thermal discomfort in winter in Lhasa as a typical location of a cold climate at high altitudes.First,we evaluated the thermal comfort incorporating solar radiation effect in winter by field measurements.Subsequently,we investigated local occupant adaptive responses(considering the impact of direct solar irradiance).This was followed by a simulation study of assessment of annual based thermal comfort and the effect on energy-saving potential by current solar adjustment.Finally,we discussed winter shading design for high altitudes for both solar shading and passive solar use at high altitudes,and evaluated thermal mass shading with solar louvers in terms of indoor environment control.The results reveal that considerable indoor overheating occurs during the whole winter season instead of summer in Lhasa,with over two-thirds of daytime beyond the comfort range.Further,various adaptive behaviors are adopted by occupants in response to overheating due to the solar radiation.Moreover,it is found that the energy-saving potential might be overestimated by 1.9 times with current window to wall ratio requirements in local design standards and building codes due to the thermal adaption by drawing curtains.The developed thermal mass shading is efficient in achieving an improved indoor thermal environment by reducing overheating time to an average of 62.2%during the winter and a corresponding increase of comfort time.展开更多
Diffuse oxygen supply is an important means to improve the indoor oxygen environment of buildings and ensure physiological and psychological health of immigrants in plateau areas.Existing research on oxygen enrichment...Diffuse oxygen supply is an important means to improve the indoor oxygen environment of buildings and ensure physiological and psychological health of immigrants in plateau areas.Existing research on oxygen enrichment strategies at high altitudes has mainly focused on confined spaces under mechanical ventilation,with few studies on the distribution of indoor oxygen concentration under natural ventilation in actual buildings.This study used a verified computational fluid dynamics(CFD)method to investigate the indoor oxygen distribution with practical consideration of natural ventilation at high altitudes.The results showed that the oxygen distribution under wind-driven natural ventilation was more nonuniform than that under buoyancy-driven natural ventilation,with the ratio of local oxygen concentration to overall-mean oxygen concentration,the k value,between 0.8 and 1.3 under wind-driven natural ventilation and between 0.9 and 1.1 under buoyancy-driven natural ventilation.The effects of meteorological condition and oxygen source position on indoor spatial oxygen distribution characteristics were explored with careful examination in human occupied zone under lying,sitting and standing postures.The results can provide implications for effective and energy saving design of indoor oxygen supply system in plateau buildings.展开更多
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
Thanks to solid archaeological work over recent years,a series of breakthroughs have been achieved in the study of the history of the Xizang Autonomous Region in Paleolithic,Neolithic and Metal Ages.
The innovative study by Zhang et al published in the World Journal of Cardiology focused on predicting 30-day mortality in patients with acute myocardial infarction complicated by ventricular septal rupture at high al...The innovative study by Zhang et al published in the World Journal of Cardiology focused on predicting 30-day mortality in patients with acute myocardial infarction complicated by ventricular septal rupture at high altitudes.Based on a retrospective analysis of 48 patients from Yunnan Province,China,the authors identified four independent predictors of mortality:Age;Elevated uric acid levels;Interleukin-6 and decreased hemoglobin.Integrating these factors into a nomogram demonstrated high predictive accuracy(area under the curve=0.939).This model addressed the critical challenge of risk stratification in the resource-limited settings typical of high-altitude areas.This editorial underscored the practical value of the nomogram for timely identification of candidates for intensive therapy and surgical intervention while emphasizing the need for model validation in multicenter cohorts to optimize the management of these patients.展开更多
Ischemic stroke is the leading cause of death in the Chinese population.The incidence of cerebral infarction is higher in high-altitude regions,particularly those above 3,500 m,than in populations residing at lower al...Ischemic stroke is the leading cause of death in the Chinese population.The incidence of cerebral infarction is higher in high-altitude regions,particularly those above 3,500 m,than in populations residing at lower altitudes[1].There are various speculations regarding the mechanisms behind this phenomenon,one of which is that the low oxygen content and cold climate at high altitudes may increase the occurrence of vascular diseases[2].The multifactorial effect of high-altitude environments on residential populations makes it challenging for researchers to determine the specific pathways through which these diseases occur.展开更多
In order to solve the problem of inter-vehicle communication （IVC） in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the...In order to solve the problem of inter-vehicle communication （IVC） in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the other is based on high altitude platform （ HAP ） communication. The system outline and networking modes of the two models are described. In the satellite communication based model, all the vehicles are equipped with vehicle-bone satellite communication on the move terminals and the communication signals between vehicles are forwarded by satellite. In the high altitude platform-based model, the HAPs are equipped with base station facilities to form aerial base stations, and vehicles can communicate with each other via common terrestrial mobile communication devices. Some key parameters such as path loss, link loss and system capacity are also computed. The analysis shows that both the two models can satisfy the requirement of IVC in the descriptive environment.展开更多
AIM:To study whether over-starvation aggravates intestinal mucosal injury and promotes bacterial and endotoxin translocation in a high-altitude hypoxic environment.METHODS:Sprague-Dawley rats were exposed to hy-pobari...AIM:To study whether over-starvation aggravates intestinal mucosal injury and promotes bacterial and endotoxin translocation in a high-altitude hypoxic environment.METHODS:Sprague-Dawley rats were exposed to hy-pobaric hypoxia at a simulated altitude of 7000 m for 72 h.Lanthanum nitrate was used as a tracer to detect intestinal injury.Epithelial apoptosis was observed with terminal deoxynucleotidyl transferase dUTP nick end labeling staining.Serum levels of diamino oxidase(DAO),malondialdehyde(MDA),glutamine(Gln),superoxide dismutase(SOD) and endotoxin were measured in intestinal mucosa.Bacterial translocation was detected in blood culture and intestinal homogenates.In addition,rats were given Gln intragastrically to observe its protective effect on intestinal injury.RESULTS:Apoptotic epithelial cells,exfoliated villi and inflammatory cells in intestine were increased with edema in the lamina propria accompanying effusion of red blood cells.Lanthanum particles were found in the intercellular space and intracellular compartment.Bacterial translocation to mesenteric lymph nodes(MLN) and spleen was evident.The serum endotoxin,DAO and MDA levels were significantly higher while the serum SOD,DAO and Gln levels were lower in intestine(P< 0.05).The bacterial translocation number was lower in the high altitude hypoxic group than in the high altitude starvation group(0.47±0.83 vs 2.38±1.45,P<0.05).The bacterial translocation was found in each organ,especially in MLN and spleen but not in peripheral blood.The bacterial and endotoxin translocations were both markedly improved in rats after treatment with Gln.CONCLUSION:High-altitude hypoxia and starvation cause severe intestinal mucosal injury and increase bacterial and endotoxin translocation,which can be treated with Gln.展开更多
AIM: To investigate the gastrointestinal bleeding (GIB) in people from lowland to high altitude and in workers on Mountain Tanggula and its causes as well as treatment and prophylaxis.METHODS: From 2001 to October 200...AIM: To investigate the gastrointestinal bleeding (GIB) in people from lowland to high altitude and in workers on Mountain Tanggula and its causes as well as treatment and prophylaxis.METHODS: From 2001 to October 2003, we studied GIB in 13 502 workers constructing the railroad on Mountain Tanggula which is 4905 m above the sea level. The incidence of GIB in workers at different altitudes was recorded. Endoscopy was performed when the workers evacuated to Golmud (2808 m) and Xining (2261 m). The available data on altitude GIB were analyzed.RESULTS: The overall incidence of GIB was 0.49% in 13 502 workers. The incidence increased with increasing altitude. The onset of symptoms in most patients was within three weeks after arrival at high altitude. Bleeding manifested as hematemesis, melaena or hematochezia, and might be occult. Endoscopic examination showed that the causes of altitude GIB included hemorrhage gastritis, gastric ulcer, duodenal ulcer, and gastric erosion. Experimental studies suggested that acute gastric mucosal lesion (AGML) could be induced by hypoxic and cold stress, which might be the pathogenesis of altitude GIB. Those who consumed large amount of alcohol, aspirin or dexamethasone were at a higher risk of developing GIB. Persons who previously suffered from peptic ulcer or high-altitude polycythemia were also at risk of developing GIB. Early diagnosis, evacuation, and treatment led to early recovery. CONCLUSION: GIB is a potentially life threatening disease, if it is not treated promptly and effectively. Early diagnosis, treatment and evacuation lead to an early recovery. Death due to altitude GIB can be avoided if early symptoms and signs are recognized.展开更多
Unmanned Aerial Vehicle（UAV） is developing towards the direction of High Altitude Long Endurance（HALE）. This will have an important influence on the stability of its airborne electronic equipment using passive the...Unmanned Aerial Vehicle（UAV） is developing towards the direction of High Altitude Long Endurance（HALE）. This will have an important influence on the stability of its airborne electronic equipment using passive thermal management. In this paper, a multi-node transient thermal model for airborne electronic equipment is set up based on the thermal network method to predict their dynamic temperature responses under high altitude and long flight time conditions. Some relevant factors are considered into this temperature prediction model including flight environment,radiation, convection, heat conduction, etc. An experimental chamber simulating a high altitude flight environment was set up to survey the dynamic thermal responses of airborne electronic equipment in a UAV. According to the experimental measurement results, the multi-node transient thermal model is verified without consideration of the effects of flight speed. Then, a modified way about outside flight speed is added into the model to improve the temperature prediction performance. Finally, the corresponding simulation code is developed based on the proposed model. It can realize the dynamic temperature prediction of airborne electronic equipment under HALE conditions.展开更多
Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Mothoda Totally 100 young male army members newly recruited from Sichuan province （4...Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Mothoda Totally 100 young male army members newly recruited from Sichuan province （400 meters above sea level） were enrolled. They were randomly divided into two groups： 50 in aminophylline group （A group） and 50 in control group （ C group）. A group and C group orally took aminophylline and placebo respectively for 10 days, 7 days before entering Lhasa （3 658 meters above sea level） by air and 3 days after it. Several parameters were measured at three time points： before drug taken, 7 days after drug taken, and 3 days after ascending high altitude. These parameters included serum levels of nitric oxide （NO）, superoxide dismutase （SOD）, catalase （CAT）, hydrogen dioxide （H2O2）, lactic acid （LA）, as well as arterial oxygen saturation （SO2）, arterial oxygen partial pressure （PaO2）, and arterial carbon dioxide partial pressure （PaCO2）. Statistical analysis was conducted to compare the difference between two groups with Stata 7.0 software system. Results There were no statistical differences between groups in hypoxia and oxidation indicators before and after drug taken in plain area. Three days after ascending high altitude, the serum levels of SOD, CAT, H202, LA, PaCO2 increased in both groups, yet to a much larger degree in C group than A group （P 〈0. 01 ） ; and NO, SO2 , PaO2 decreased more markedly in C group （ P 〈 0. 05 for NO, P 〈 0. 0001 for SO2 and PaO2 ）. Conclusion Aminophylline has significant anti-hypoxia and anti-oxidation effects at high altitude.展开更多
Abstract High altitude test facilities are required to test the high area ratio nozzles operating at the upper stages of rocket in the nozzle full flow conditions. It is typically achieved by creating the ambient pres...Abstract High altitude test facilities are required to test the high area ratio nozzles operating at the upper stages of rocket in the nozzle full flow conditions. It is typically achieved by creating the ambient pressure equal or less than the nozzle exit pressure. On average, air/GN2 is used as active gas for ejector system that is stored in the high pressure cylinders. The wind tunnel facilities are used for conducting aerodynamic simulation experiments at/under various flow velocities and operating conditions. However, constructing both of these facilities require more laboratory space and expensive instruments. Because of this demerit, a novel scheme is implemented for conducting wind tunnel experiments by using the existing infrastructure available in the high altitude testing （HAT） facility. This article presents the details about the methods implemented for suitably modifying the sub-scale HAT facility to conduct wind tunnel experiments. Hence, the design of nozzle for required area ratio A/A＊, realization of test section and the optimized configuration are focused in the present analysis. Specific insights into various rocket models including high thrust cryogenic engines and their holding mechanisms to conduct wind tunnel experiments in the HAT facility are analyzed. A detailed CFD analysis is done to propose this conversion without affecting the existing functional requirements of the HAT facility.展开更多
The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway, as suggested by earlier studies. To test the adaptive role of the previously reported candidate gene...The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway, as suggested by earlier studies. To test the adaptive role of the previously reported candidate gene EP300 （histone acetyltransferase p300）, we conducted resequencing of a 108.9 kb gene region of EP300 in 80 unrelated Tibetans. The allele-frequency and haplotype-based neutrality tests detected signals of positive Darwinian selection on EP300 in Tibetans, with a group of variants showing allelic divergence between Tibetans and lowland reference populations, including Han Chinese, Europeans, and Africans. Functional prediction suggested the involvement of multiple EP300 variants in gene expression regulation. More importantly, genetic association tests in 226 Tibetans indicated significant correlation of the adaptive EP300 variants with blood nitric oxide （NO） concentration. Collectively, we propose that EP300 harbors adaptive variants in Tibetans, which might contribute to high-altitude adaptation through regulating NO production.展开更多
Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at...Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level. Methods A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing. Results The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both P<0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both P<0.001). Conclusions Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.展开更多
This paper presents a comprehensive simulation for a high-altitude dual-balloon system which consists of zero-and super-pressure balloons. Preliminary calculations were established to describe the basic concept of the...This paper presents a comprehensive simulation for a high-altitude dual-balloon system which consists of zero-and super-pressure balloons. Preliminary calculations were established to describe the basic concept of the new integrated system. A mathematical model was investigated to simulate the ascending and floating processes which considered the atmospheric conditions and thermodynamic variations. Based on the simulation, results showed that the floating altitude stability between daytime and nighttime was improved. This integrated system supports higher floating altitude levels than those of ordinary balloons and extends the lifetime of floating balloon systems. Moreover, results demonstrated that the integrated system was lighter than ordinary balloons, saving useful weight for effective payload. Furthermore, exploiting the advantages of both kinds of balloons while avoiding the difficulties was a significant goal in the current design to promote the floating performance of high-altitude balloons technology.展开更多
文摘Populations living at high altitudes （HAs）, particularly in the Peruvian Andes, are characterized by a mixture of subjects with erythrocytosis （16 g dl-1〈haemoglobin （Hb）≤21 gdl-1） and others with excessive erythrocytosis （EE） （Hb〉21 g dl-1）. Elevated haemoglobin values （EE） are associated with chronic mountain sickness, a condition reflecting the lack of adaptation to HA. According to current data, native men from regions of HA are not adequately adapted to live at such altitudes if they have elevated serum testosterone levels. This seems to be due to an increased conversion of dehydroepiandrosterone sulphate （DH EAS） to testosterone. Men with erythrocytosis at HAs show higher serum androstenedione levels and a lower testosterone/androstenedione ratio than men with EE, suggesting reduced 17beta-hydroxysteroid dehydrogenase （17beta-HSD） activity. Lower 17beta-HSD activity via A4-steroid production in men with erythrocytosis at HA may protect against elevated serum testosterone levels, thus preventing EE. The higher conversion of DHEAS to testosterone in subjects with EE indicates increased 17beta-HSD activity via the A5-pathway. Currently, there are various situations in which people live （human biodiversity） with low or high haemoglobin levels at HA. Antiquity could be an important adaptation component for life at HA, and testosterone seems to participate in this process.
文摘Background:This study aimed to illustrate the prevalence of CHD by screening children in extremely high-altitudeareas(over 4000 m to even 5000 m above sea level)and explore an aid model for early diagnosis and treatmentfor the Tibetan population.Methods:A total of 2242 students from different schools in Ngamring County,Xigaze City,Tibet from September 2019 to September 2020 were selected for screening.The students were examinedthrough the inquiry of their current medical history and family history,cardiac auscultation and a physicalexamination,in order to screen out the suspected cases of CHD,and then the suspected cases were confirmed bycardiac color ultrasound examinations.After that,positive patients were be transferred to Shandong Province forfree treatment.Results:The prevalence of CHD among children in Ngamring County was 3.70%(83 cases),which is the highest incidence rate ever reported.The most common type of CHD was patent ductus arteriosus(PDA),accounting for 55.42%of the total number of cases screened,followed by atrial septal defect(ASD)andventricular septal defect(VSD),accounting for 28.92%and 12.05%,respectively.The prevalence of CHD in childrenat high altitude was significantly higher than that in children at low altitude.The children with CHD weretransferred to Shandong Province for surgery,the operations were successful and their recoveries went well.Conclusions:The results show that high altitude is closely related to the prevalence of CHD,and the incidencein Ngamring County is much higher than that in previous reports.
基金supported by the National Key Research and Development Program of China(2023YFF1000401)the National Natural Science Foundation of China(32025027),Pinduoduo-China Agricultural University Research Fund(PC2023A01003)+2 种基金New Cornerstone Science Foundation through the XPLORER PRIZE,Hainan Yazhou Bay Seed Laboratory(B21HJ0111)Sanya Yazhouwan Science and Technology City Administration(SYND-2022-26)the Chinese Universities Scientific Fund(2020TC149 and 2022TC138).
文摘Maize(Zea mays ssp.mays)was domesticated approximately 9,000 years ago from Zea mays ssp.parviglumis,a lowland teosinte native to southwestern Mexico(Matsuoka et al.,2002).From the tropical origin,maize has spread into a wide range of temperate regions with high latitudes and altitudes.Flowering time is a critical trait determining plant local adaptation.Several flowering time genes contributing to maize latitudinal adaptation have been identified(Yang et al.,2013;Guo et al.,2018;Huang et al.,2018;Liang et al.,2019;Wu et al.,2023).In contrast,the genetic mechanisms enabling maize adaptation to high-altitude environments remain poorly understood.
基金Supported by Army Logistics Department Health Bureau Project,No.QJGYXYJZX-012.
文摘BACKGROUND Due to the dry and cold climate,the obvious temperature difference between day and night,and the low oxygen content of the air in the plateau area,people are prone to upper respiratory tract diseases,and often the condition is prolonged,and the patients are prone to anxiety and uneasiness,which may be related to the harshness of the plateau environment,somatic discomfort due to the lack of oxygen,anxiety about the disease,and other factors.AIM To investigate the effects of cognitive behavioral therapy(CBT)on anxiety,sleep disorders,and hypoxia tolerance in patients with high-altitude respiratory diseases.METHODS A total of 2337 patients with high-altitude-related respiratory diseases treated at our hospital between November 2023 and January 2024 were selected as the study subjects.The subjects’pre-high-altitude residential altitude was approximately 1700 meters.They were divided into two groups.Both groups were given symptomatic treatment,and the control group implemented conventional nursing intervention,while the research group simultaneously conducted CBT intervention;assessed the degree of health knowledge of the two groups,and applied the Hamilton Anxiety Scale and the Pittsburgh Sleep Quality Index to assess the anxiety and sleep quality of the patients before and after the intervention,respectively.It also observed the length and efficiency of sleep,and detected the level of serum hypoxia inducible factor-1α,erythropoietin(EPO)and clinical intervention before and after intervention.EPO levels,and investigated satisfaction with the clinical intervention.RESULTS The rate of excellent health knowledge in the intervention group was 93.64%,which was higher than that in the control group(74.23%;P<0.05).Before the intervention,there was no significant difference in Hamilton Anxiety Scale and Pittsburgh Sleep Quality Index scores between the two groups(P>0.05),and after the intervention,the scores of the study group were significantly lower than those of the control group(P<0.05).There was no significant difference in sleep duration and sleep efficiency between the groups before the intervention(P>0.05),and after the intervention,the scores of the study group were significantly larger than those of the control group(P<0.05).There was no significant difference in serum hypoxia inducible factor-1αand EPO between the two groups before intervention(P>0.05),and both research groups were significantly lower than the control group after intervention(P<0.05).According to the questionnaire survey,the intervention satisfaction of the study group was 95.53%,which was higher than that of the control group(80.14%;P<0.05).CONCLUSION The CBT intervention in the treatment of patients with high-altitude-related respiratory diseases helps improve patients'health knowledge,relieve anxiety,improve sleep quality and hypoxia tolerance,and improve nursing satisfaction.
基金We extend our gratitude to the funding supports of the National Natural Science Foundation of China(No.51878532)the Shaanxi Province Natural Science Foundation Research Project of China(No.2019JQ-392)the Independent Research and Development project of State Key Laboratory of Green Building in Western China(No.LSZZ202008).
文摘The hypoxic environment at high altitudes causes various sleep disorders.Diffuse oxygen enrichment is an effective way to alleviate sleep disorders and improve the built environment in high altitude areas.In this study,a novel point source local diffuse oxygen supply method was proposed to improve the sleeping oxygen environment.The oxygen supply performance was investigated by the computational fluid dynamics(CFD)method including the oxygen concentration and air velocity distributions.A sleeping experiment was conducted on the plateau to validate the CFD model.The occupied zone including the inhalation zone and the active zone was defined.The results showed that the oxygen concentration showed a rapid rise,then decreased slowly,and finally tended to be stable.The oxygen concentration after stabilization was remarkably influenced by indoor ventilation rate.The sleeping environment’s improvement was examined considering the oxygen enrichment efficiency,uniformity,stability and human comfort demand.The optimal strategies were recommended with a ventilation rate of 1 air change per hour,supplied oxygen concentration of 90%;and jet distance of 0.50 m.The study contributes to improving the oxygen environment and human sleep quality in an effective and energy-saving approach to the sustainable development of buildings in high altitude areas.
基金supported by the National Natural Science Foundation of China(No.51278525)the grant of the Top Youth Programme of Wuhan University.
文摘The solar incidence on an indoor environment and its occupants has significant impacts on indoor thermal comfort.It can bring favorable passive solar heating and can result in undesired overheating(even in winter).This problem becomes more critical for high altitudes with high intensity of solar irradiance,while received limited attention.In this study,we explored the specific overheating and rising thermal discomfort in winter in Lhasa as a typical location of a cold climate at high altitudes.First,we evaluated the thermal comfort incorporating solar radiation effect in winter by field measurements.Subsequently,we investigated local occupant adaptive responses(considering the impact of direct solar irradiance).This was followed by a simulation study of assessment of annual based thermal comfort and the effect on energy-saving potential by current solar adjustment.Finally,we discussed winter shading design for high altitudes for both solar shading and passive solar use at high altitudes,and evaluated thermal mass shading with solar louvers in terms of indoor environment control.The results reveal that considerable indoor overheating occurs during the whole winter season instead of summer in Lhasa,with over two-thirds of daytime beyond the comfort range.Further,various adaptive behaviors are adopted by occupants in response to overheating due to the solar radiation.Moreover,it is found that the energy-saving potential might be overestimated by 1.9 times with current window to wall ratio requirements in local design standards and building codes due to the thermal adaption by drawing curtains.The developed thermal mass shading is efficient in achieving an improved indoor thermal environment by reducing overheating time to an average of 62.2%during the winter and a corresponding increase of comfort time.
基金We extend our gratitude to the funding supports of National Natural Science Foundation of China(No.51878532)Shaanxi Province Natural Science Foundation Research Project of China(No.2019JQ-392)Independent Research and Development project of State Key Laboratory of Green Building in Western China(No.LSZZ202008).
文摘Diffuse oxygen supply is an important means to improve the indoor oxygen environment of buildings and ensure physiological and psychological health of immigrants in plateau areas.Existing research on oxygen enrichment strategies at high altitudes has mainly focused on confined spaces under mechanical ventilation,with few studies on the distribution of indoor oxygen concentration under natural ventilation in actual buildings.This study used a verified computational fluid dynamics(CFD)method to investigate the indoor oxygen distribution with practical consideration of natural ventilation at high altitudes.The results showed that the oxygen distribution under wind-driven natural ventilation was more nonuniform than that under buoyancy-driven natural ventilation,with the ratio of local oxygen concentration to overall-mean oxygen concentration,the k value,between 0.8 and 1.3 under wind-driven natural ventilation and between 0.9 and 1.1 under buoyancy-driven natural ventilation.The effects of meteorological condition and oxygen source position on indoor spatial oxygen distribution characteristics were explored with careful examination in human occupied zone under lying,sitting and standing postures.The results can provide implications for effective and energy saving design of indoor oxygen supply system in plateau buildings.
文摘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.
文摘Thanks to solid archaeological work over recent years,a series of breakthroughs have been achieved in the study of the history of the Xizang Autonomous Region in Paleolithic,Neolithic and Metal Ages.
文摘The innovative study by Zhang et al published in the World Journal of Cardiology focused on predicting 30-day mortality in patients with acute myocardial infarction complicated by ventricular septal rupture at high altitudes.Based on a retrospective analysis of 48 patients from Yunnan Province,China,the authors identified four independent predictors of mortality:Age;Elevated uric acid levels;Interleukin-6 and decreased hemoglobin.Integrating these factors into a nomogram demonstrated high predictive accuracy(area under the curve=0.939).This model addressed the critical challenge of risk stratification in the resource-limited settings typical of high-altitude areas.This editorial underscored the practical value of the nomogram for timely identification of candidates for intensive therapy and surgical intervention while emphasizing the need for model validation in multicenter cohorts to optimize the management of these patients.
基金supported by the National Natural Science Foundation of Chongqing,China(CSTB2022NSCQ-MSX1100)National Natural Science Foundation of China(grant no.82101499).
文摘Ischemic stroke is the leading cause of death in the Chinese population.The incidence of cerebral infarction is higher in high-altitude regions,particularly those above 3,500 m,than in populations residing at lower altitudes[1].There are various speculations regarding the mechanisms behind this phenomenon,one of which is that the low oxygen content and cold climate at high altitudes may increase the occurrence of vascular diseases[2].The multifactorial effect of high-altitude environments on residential populations makes it challenging for researchers to determine the specific pathways through which these diseases occur.
基金FThe National High Technology Research and Development Program of China (863 Program) (No. 2008AA01Z205)the Specialized Development Foundation for the Achievement Transformation of Jiangsu Province (No. BA2010023)+1 种基金the Natural Science Foundation of Hainan Province (No. 609008)Sanya University and Local Government Technological Cooperative Project (No. 2010YD29)
文摘In order to solve the problem of inter-vehicle communication （IVC） in vast and desolate areas such as the desert and the Gobi, two vehicle network models are proposed. One is based on satellite communication and the other is based on high altitude platform （ HAP ） communication. The system outline and networking modes of the two models are described. In the satellite communication based model, all the vehicles are equipped with vehicle-bone satellite communication on the move terminals and the communication signals between vehicles are forwarded by satellite. In the high altitude platform-based model, the HAPs are equipped with base station facilities to form aerial base stations, and vehicles can communicate with each other via common terrestrial mobile communication devices. Some key parameters such as path loss, link loss and system capacity are also computed. The analysis shows that both the two models can satisfy the requirement of IVC in the descriptive environment.
基金Supported by Scientific and Technical Research Funds from Chinese PLA during the Eleventh Five-Year Plan Period,No. 2008G093National Natural Science Foundation of China,No. 30900715National Science and Technology Ministry,No. 2009BAI85B03
文摘AIM:To study whether over-starvation aggravates intestinal mucosal injury and promotes bacterial and endotoxin translocation in a high-altitude hypoxic environment.METHODS:Sprague-Dawley rats were exposed to hy-pobaric hypoxia at a simulated altitude of 7000 m for 72 h.Lanthanum nitrate was used as a tracer to detect intestinal injury.Epithelial apoptosis was observed with terminal deoxynucleotidyl transferase dUTP nick end labeling staining.Serum levels of diamino oxidase(DAO),malondialdehyde(MDA),glutamine(Gln),superoxide dismutase(SOD) and endotoxin were measured in intestinal mucosa.Bacterial translocation was detected in blood culture and intestinal homogenates.In addition,rats were given Gln intragastrically to observe its protective effect on intestinal injury.RESULTS:Apoptotic epithelial cells,exfoliated villi and inflammatory cells in intestine were increased with edema in the lamina propria accompanying effusion of red blood cells.Lanthanum particles were found in the intercellular space and intracellular compartment.Bacterial translocation to mesenteric lymph nodes(MLN) and spleen was evident.The serum endotoxin,DAO and MDA levels were significantly higher while the serum SOD,DAO and Gln levels were lower in intestine(P< 0.05).The bacterial translocation number was lower in the high altitude hypoxic group than in the high altitude starvation group(0.47±0.83 vs 2.38±1.45,P<0.05).The bacterial translocation was found in each organ,especially in MLN and spleen but not in peripheral blood.The bacterial and endotoxin translocations were both markedly improved in rats after treatment with Gln.CONCLUSION:High-altitude hypoxia and starvation cause severe intestinal mucosal injury and increase bacterial and endotoxin translocation,which can be treated with Gln.
基金Supported by the grant LS-CNNSF-30393130, and 973 Program 2006 CB 504100, CB708514, China
文摘AIM: To investigate the gastrointestinal bleeding (GIB) in people from lowland to high altitude and in workers on Mountain Tanggula and its causes as well as treatment and prophylaxis.METHODS: From 2001 to October 2003, we studied GIB in 13 502 workers constructing the railroad on Mountain Tanggula which is 4905 m above the sea level. The incidence of GIB in workers at different altitudes was recorded. Endoscopy was performed when the workers evacuated to Golmud (2808 m) and Xining (2261 m). The available data on altitude GIB were analyzed.RESULTS: The overall incidence of GIB was 0.49% in 13 502 workers. The incidence increased with increasing altitude. The onset of symptoms in most patients was within three weeks after arrival at high altitude. Bleeding manifested as hematemesis, melaena or hematochezia, and might be occult. Endoscopic examination showed that the causes of altitude GIB included hemorrhage gastritis, gastric ulcer, duodenal ulcer, and gastric erosion. Experimental studies suggested that acute gastric mucosal lesion (AGML) could be induced by hypoxic and cold stress, which might be the pathogenesis of altitude GIB. Those who consumed large amount of alcohol, aspirin or dexamethasone were at a higher risk of developing GIB. Persons who previously suffered from peptic ulcer or high-altitude polycythemia were also at risk of developing GIB. Early diagnosis, evacuation, and treatment led to early recovery. CONCLUSION: GIB is a potentially life threatening disease, if it is not treated promptly and effectively. Early diagnosis, treatment and evacuation lead to an early recovery. Death due to altitude GIB can be avoided if early symptoms and signs are recognized.
基金the financial support of National Key R&D Program of China (No.2017YFB1201100)
文摘Unmanned Aerial Vehicle（UAV） is developing towards the direction of High Altitude Long Endurance（HALE）. This will have an important influence on the stability of its airborne electronic equipment using passive thermal management. In this paper, a multi-node transient thermal model for airborne electronic equipment is set up based on the thermal network method to predict their dynamic temperature responses under high altitude and long flight time conditions. Some relevant factors are considered into this temperature prediction model including flight environment,radiation, convection, heat conduction, etc. An experimental chamber simulating a high altitude flight environment was set up to survey the dynamic thermal responses of airborne electronic equipment in a UAV. According to the experimental measurement results, the multi-node transient thermal model is verified without consideration of the effects of flight speed. Then, a modified way about outside flight speed is added into the model to improve the temperature prediction performance. Finally, the corresponding simulation code is developed based on the proposed model. It can realize the dynamic temperature prediction of airborne electronic equipment under HALE conditions.
文摘Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Mothoda Totally 100 young male army members newly recruited from Sichuan province （400 meters above sea level） were enrolled. They were randomly divided into two groups： 50 in aminophylline group （A group） and 50 in control group （ C group）. A group and C group orally took aminophylline and placebo respectively for 10 days, 7 days before entering Lhasa （3 658 meters above sea level） by air and 3 days after it. Several parameters were measured at three time points： before drug taken, 7 days after drug taken, and 3 days after ascending high altitude. These parameters included serum levels of nitric oxide （NO）, superoxide dismutase （SOD）, catalase （CAT）, hydrogen dioxide （H2O2）, lactic acid （LA）, as well as arterial oxygen saturation （SO2）, arterial oxygen partial pressure （PaO2）, and arterial carbon dioxide partial pressure （PaCO2）. Statistical analysis was conducted to compare the difference between two groups with Stata 7.0 software system. Results There were no statistical differences between groups in hypoxia and oxidation indicators before and after drug taken in plain area. Three days after ascending high altitude, the serum levels of SOD, CAT, H202, LA, PaCO2 increased in both groups, yet to a much larger degree in C group than A group （P 〈0. 01 ） ; and NO, SO2 , PaO2 decreased more markedly in C group （ P 〈 0. 05 for NO, P 〈 0. 0001 for SO2 and PaO2 ）. Conclusion Aminophylline has significant anti-hypoxia and anti-oxidation effects at high altitude.
文摘Abstract High altitude test facilities are required to test the high area ratio nozzles operating at the upper stages of rocket in the nozzle full flow conditions. It is typically achieved by creating the ambient pressure equal or less than the nozzle exit pressure. On average, air/GN2 is used as active gas for ejector system that is stored in the high pressure cylinders. The wind tunnel facilities are used for conducting aerodynamic simulation experiments at/under various flow velocities and operating conditions. However, constructing both of these facilities require more laboratory space and expensive instruments. Because of this demerit, a novel scheme is implemented for conducting wind tunnel experiments by using the existing infrastructure available in the high altitude testing （HAT） facility. This article presents the details about the methods implemented for suitably modifying the sub-scale HAT facility to conduct wind tunnel experiments. Hence, the design of nozzle for required area ratio A/A＊, realization of test section and the optimized configuration are focused in the present analysis. Specific insights into various rocket models including high thrust cryogenic engines and their holding mechanisms to conduct wind tunnel experiments in the HAT facility are analyzed. A detailed CFD analysis is done to propose this conversion without affecting the existing functional requirements of the HAT facility.
基金supported by grants from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB13010000)the National Natural Science Foundation of China(91631306 to BS,31671329 to XQ,31460287 to Ou,31501013 to HZ,and 31360032 to CC)+2 种基金the National 973 program(2012CB518202 to TW)the State Key Laboratory of Genetic Resources and Evolution(GREKF15-05,GREKF16-04)the Zhufeng Scholar Program of Tibetan University
文摘The genetic adaptation of Tibetans to high altitude hypoxia likely involves a group of genes in the hypoxic pathway, as suggested by earlier studies. To test the adaptive role of the previously reported candidate gene EP300 （histone acetyltransferase p300）, we conducted resequencing of a 108.9 kb gene region of EP300 in 80 unrelated Tibetans. The allele-frequency and haplotype-based neutrality tests detected signals of positive Darwinian selection on EP300 in Tibetans, with a group of variants showing allelic divergence between Tibetans and lowland reference populations, including Han Chinese, Europeans, and Africans. Functional prediction suggested the involvement of multiple EP300 variants in gene expression regulation. More importantly, genetic association tests in 226 Tibetans indicated significant correlation of the adaptive EP300 variants with blood nitric oxide （NO） concentration. Collectively, we propose that EP300 harbors adaptive variants in Tibetans, which might contribute to high-altitude adaptation through regulating NO production.
基金Supported by National Natural Science Foundation of China (30393130, 30470651)National Basic Research Program of China (973 Program) (2006BAI19B07, 2006CB504103)National Key Laboratory Specific Fund (2060204)
文摘Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level. Methods A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing. Results The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both P<0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both P<0.001). Conclusions Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.
文摘This paper presents a comprehensive simulation for a high-altitude dual-balloon system which consists of zero-and super-pressure balloons. Preliminary calculations were established to describe the basic concept of the new integrated system. A mathematical model was investigated to simulate the ascending and floating processes which considered the atmospheric conditions and thermodynamic variations. Based on the simulation, results showed that the floating altitude stability between daytime and nighttime was improved. This integrated system supports higher floating altitude levels than those of ordinary balloons and extends the lifetime of floating balloon systems. Moreover, results demonstrated that the integrated system was lighter than ordinary balloons, saving useful weight for effective payload. Furthermore, exploiting the advantages of both kinds of balloons while avoiding the difficulties was a significant goal in the current design to promote the floating performance of high-altitude balloons technology.
