Oxygen enrichment of room air is an effective way to resist hypoxia at high altitude, but it may introduce a potential fire hazard. In common, the burning rate of light and thin homogeneous solid in oxygen enriched atmosphere was used to assess the fire hazard. For the purpose of measuring the burning rate of light and thin homogeneous solid in oxygen enriched atmosphere, we used the methods of laser contact ignition and direct calculation of burning rate, and invented a device that includes mixing gas system, ignition equipment, system of measuring the burning rate and self-made specimen frame. By using the homemade device, we studied the burning rate of filter paper under low pressure and in oxygen-enriched atmosphere and in that of the oxygen concentration of reached stationary burning rate. The results showed that this device was simple, and could obtain the burning rate of light and thin homogeneous solid quantitatively.
Air Pressure ; Altitude ; Atmosphere Exposure Chambers ; Environment, Controlled ; Equipment Design ; Fires ; prevention & control ; Oxygen ; analysis

The special environmental features of high altitude, such as hypobaric hypoxia, low temperature, arid, high solar radiation, variable climate and geochemical anomaly, cause great effects on human physiology and health. It will provide valuable references and new ideas to study drug's metabolism in special environment of high altitude hypoxia, and give the guidance to clinical reasonable medication, avoiding adverse reactions and personalized medicine in plateau areas. This article reviewed the effect of high altitude hypoxia on drug metabolism, elaborated metabolic characteristics of some drugs and the activity and expression of drug metabolism enzymes under hypoxia environment at high altitude, and discussed related mechanism.
Altitude ; Climate ; Cold Temperature ; Humans ; Hypoxia ; Pharmaceutical Preparations ; metabolism

Cerebral arterial air embolism (CAAE), although infrequent, is a complication that can occur at any time during an invasive medical procedure. We experienced two cases of CAAE during cerebral angiography accidentally. The author reports the two cases of CAAE wherein air emboli dissolved spontaneously and immediately under normal atmospheric pressure, not under therapeutic hyperbaric environment. One of the cases shows entire dissolution of the air embolus on the moving image. This report shows that arterial air embolus can be absorbed spontaneously, and air embolus size is one of the factors that influence air embolus dissolution besides hyperbaric oxygen condition.
Absorption* ; Atmospheric Pressure ; Cerebral Angiography ; Embolism* ; Embolism, Air ; Oxygen

PURPOSE: This retrospective study was conducted to estimate the effects of climate factors and air pollution on asthma exacerbations using a case-crossover analysis. METHODS: Patients who visited the emergency department (ED) of 2 university hospitals in Chuncheon for asthma exacerbations from January 1, 2006, to December 31, 2011, were enrolled. Daily average data for meteorological factors (temperature, daily temperature range, relative humidity, wind speed, atmospheric pressure, presence of rain, solar irradiation, and presence of fog) and the daily average levels of gaseous air pollutants (SO2, NO2, O3, CO, and PM10) were obtained. A case-crossover analysis was performed using variables about the weather and air pollution at 1-week intervals between cases and controls before and after ED visits. RESULTS: There were 660 ED visits by 583 patients with asthma exacerbations. Low relative humidity (lag 1 and 2) and high wind speed (lag 1, 2, and 3) were associated with ED visits for asthma. Fog (lag 2) showed protective effects against asthma exacerbations in Chuncheon (risk increase: -29.4% [95% CI=-46.3% to -7.2%], P=0.013). These relationships were stronger in patients ≤19 years old than in those >60 years old. High levels of ambient CO (lag 1, 2, and 3) and NO2 (lag 2 and 3) were associated with decreased ED visits for asthma. However, there were no significant relationships among levels of ambient CO or NO2 and asthma exacerbations after adjusting for wind speed and relative humidity. CONCLUSIONS: High wind speed and low humidity were associated with an increased risk of asthma ED visits. Fog was associated with a decreased risk of asthma ED visits after controlling for seasonal variations in weather and air pollution.
Air Pollutants ; Air Pollution* ; Asthma* ; Atmospheric Pressure ; Climate ; Emergencies* ; Emergency Service, Hospital* ; Gangwon-do* ; Hospitals, University ; Humans ; Humidity ; Korea* ; Meteorological Concepts ; Rain ; Retrospective Studies ; Seasons ; Weather* ; Wind

No abstract available.
Aviation* ; Cosmic Radiation*

OBJECTIVETo provide scientific basis for natural cultivation of Fritillaria cirrhosa.

METHODThe cluster analysis to the Bray--Curtis distance coefficient of community plot was carried out to divide the community types of F. cirrhosa.

RESULT AND CONCLUSIONThe community of F. cirrhosa's natural cultivation can be divided into six types: Sibiraea angustata community, Rhododendron litangense community, Salix sclerophylla community, Dasiphora fruticosa + Spiraea alpina + S. myrtilloides community, Sabina pingii var. wilsonii community, Polygonum viviparum + P. sphaerostachyum community, and the ecological characteristics such as the composition of community and ecological distribution have been showed.

Altitude ; China ; Climate ; Cluster Analysis ; Conservation of Natural Resources ; methods ; Ecosystem ; Fritillaria ; growth & development ; Pharmacognosy ; Plants, Medicinal ; growth & development ; Temperature

OBJECTIVE: We analyzed the association between regional weather and temporal changes on the daily occurrence of trauma emergencies and their severity. METHODS: In this cross-sectional prospective study, we investigated daily atmospheric patterns in trauma episodes in 1,344 patients in Cheongju city, South Korea, from January 2016 to December 2016 and analyzed the association of trauma occurrence and Injury Severity Scores (ISS) with weather conditions on a daily scale. RESULTS: The mean age of trauma patients was 53.0±23.8 years and average ISS was 9.0±2.0. Incidence of trauma was positively correlated with average temperature (r=0.512, P < 0.001) and atmospheric pressure (r=0.332, P=0.010) and negatively correlated with air pollutants (particulate matter less than 2.5 µm³ [PM2.5], r=−0.629, P < 0.001; particulate matter less than 10 µm³ [PM10], r=−0.679, P < 0.001). ISS was not significantly correlated with climate parameters and air pollutants, and variability was observed in the frequency and severity of trauma by time of day (highest occurrence, 16–20 pm; highest ISS, 4–8 am), day of the week (highest occurrence and highest ISS, Saturday), month of the year (highest occurrence, July; highest ISS, November), and season (highest incidence, summer; highest ISS, autumn). CONCLUSION: The study shows a positive relationship between trauma occurrence and specific weather conditions, such as atmospheric temperature and pressure. There was a negative relationship between concentrations of PM2.5 or PM10, and trauma occurrence. However, no correlation was observed between weather conditions or the concentrations of air pollutants and ISS. In addition, seasonal, circaseptan, and circadian variations exist in trauma occurrence and severity. Thus, we suggest that evaluation of a larger, population-based data set is needed to further investigate and confirm these relationships.
Air Pollutants* ; Atmospheric Pressure ; Chungcheongbuk-do ; Climate ; Dataset ; Emergencies ; Humans ; Incidence ; Injury Severity Score ; Korea ; Particulate Matter ; Prospective Studies ; Seasons* ; Weather

For the determination of absorbed dose to water from a linear accelerator photon beams, it needs a exposure calibration factor Nx or air kerma calibration factor Nk of air ionization chamber. We used the exposure calibration factor Nx to find the absorbed dose calibration factors of water in a reference source through the TG-21 and TRS-277 protocol. TG-21 used for determine the absorbed dose in accuracy, but it required complex calculations including the chamber dependent factors. The authors obtained the absorbed dose calibration factor NdwCo-60 for reduce the complex calculations with unknown Ndw only with Nx or Nk calibration factor in a TM31010 (S/N 1055, 1057) ionization chambers. The results showed the uncertainty of calculated Ndw of IC-15 which was known the Nx and Ndw is within -0.6% in TG-21, but 1.0% in TRS-277. and TM31010 was compared the Ndw of SSDL to that of PSDL as shown the 0.4%, -2.8% uncertainty, respectively. The authors experimented with good agreement the calculated Ndw is reliable for cross check the discrepancy of the calibration factor with unknown that of TM31010 and IC-15 chamber.
Air Ionization ; Calibration ; Particle Accelerators ; Uncertainty ; Water

The wild plant Dactylorhiza hatagirea commonly used in Tibetan medicine. In recent years, it is on the verge of extinction due to improper excavation and habitat deterioration. Based on the literature review, and the meteorological and ecological data of Qinghai Province and data derived from the field survey, this study took the altitude, humidity index, annual average wind speed, monthly average sunshine, precipitation and temperature in growing season, soil type and vegetation type as the zoning indexes, and applied ArcGIS software for spatial superposition analysis. The results showed that the D. hatagirea was primarily found in the alpine meadow in the east and south of Qinghai Province. The overall suitable area was about 30 700 km~2. Taking Qinghai Lake as the boundary for reference, the area in the south appeared to be more suitable, while the area in the east appeared to be secondary in suitability. Henan County, Zeku County, Jiuzhi County and Banma County were the main suitable areas covering the expanse of 12 454 km~2. Through the field verification, such zoning results appeared to be accurate, precise and illustrative. The spatial distribution of ecological suitability provides the decision-making basis for the resource investigation, environment protection and comprehensive resource management. It also provides the empirical case for developing the interdisciplinary research method in the suitability study of medicinal plants.
Altitude ; China ; Conservation of Natural Resources ; Ecosystem ; Plants, Medicinal ; Soil

BACKGROUND AND OBJECTIVES: Epistaxis may be related to changes in weather, but this relationship has not been well-defined. We investigated the effects of climate fluctuations (temperature, humidity, and barometric pressure) on the number of emergency department (ED) visits for epistaxis. SUBJECTS AND METHOD: In total, our study population included 1910 patients who visited the ED of a large, urban hospital during a 5-year period for epistaxis. Patients with clear etiology for epistaxis (trauma, iatrogenic, coagulopathy, and/or hypertension) were excluded, leaving 912 patients for subsequent analysis. Daily climate data was collected through the Korea Meteorological Administration. Correlation between epistaxis ED visits and weather variables were investigated using Poisson distribution and multiple regression analysis. The effect of climate factor was evaluated on the day and up to 3 days prior to ED presentation. Additionally, analyses were conducted separately for children (<15 years-old), adults (15-64 years-old), and elderly patients (> or =65 years-old). RESULTS: Changes in the lowest temperature 2 days prior to ED presentation significantly increased the number of ED visits for epistaxis (beta=-0.043, p=0.033). No associations were found between the number of ED visits and changes in humidity or atmospheric pressure. However, in children, interday changes in the highest atmospheric pressure between 2 and 3 days prior to ED presentation were both significantly associated with increased number of epistaxis ED visits. CONCLUSION: Cold temperatures 2 days prior to ED presentation were related to the increased incidence of epistaxis. Fluctuations in barometric pressure appear to influence the number of pediatric ED visits for epistaxis.
Adult ; Aged ; Atmospheric Pressure ; Child ; Climate ; Cold Temperature ; Emergency Service, Hospital* ; Epistaxis* ; Hospitals, Urban ; Humans ; Humidity ; Incidence ; Korea ; Meteorological Concepts* ; Weather