Cosmic Radiation at Very High Altitudes Near the Geomagnetic Equator

1954 ◽  
Vol 95 (2) ◽  
pp. 531-537 ◽  
Author(s):  
Martin A. Pomerantz
1949 ◽  
Vol 75 (1) ◽  
pp. 69-80 ◽  
Author(s):  
Martin A. Pomerantz

1992 ◽  
Vol 24 (2) ◽  
pp. 111-117
Author(s):  
W. Obermayer ◽  
J. Poelt

Abstract The lichen Lecanora somervellii Paulson, first described from the northern slopes of Mt Everest in Tibet, has been collected at four other localities in the High Himalayas, at altitudes between 3750 and 5540 m. As the type material appears to be missing, a neotype is designated here. The species has an unusual lemon yellow colour due to the pigment calycin; this compound is in addition to usnic acid, which is widespread in Lecanora. Lecanora somervellii is otherwise very similar in essential characters to the complex including Lecanora concolor Ram. and L. orbicularis (Schaerer) Vainio, high alpine species well-known, for example, from the Alps. It is supposed, that L. somervellii is derived from this aggregate by the production of calycin (in addition to usnic acid), which acts as an additional protective pigment at these very high altitudes.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ivan Lopez ◽  
Reinaldo Aravena ◽  
Daniel Soza ◽  
Alicia Morales ◽  
Silvia Riquelme ◽  
...  

The Chilean workforce has over 200,000 people that are intermittently exposed to altitudes over 4,000 m. In 2012, the Ministry of Health provided a technical guide for high-altitude workers that included a series of actions to mitigate the effects of hypoxia. Previous studies have shown the positive effect of oxygen enrichment at high altitudes. The Atacama Large Millimeter/submillimeter Array (ALMA) radiotelescope operates at 5,050 m [Array Operations Site (AOS)] and is the only place in the world where pressure swing adsorption (PSA) and liquid oxygen technologies have been installed at a large scale. These technologies reduce the equivalent altitude by increasing oxygen availability. This study aims to perform a retrospective comparison between the use of both technologies during operation in ALMA at 5,050 m. In each condition, variables such as oxygen (O2), temperature, and humidity were continuously recorded in each AOS rooms, and cardiorespiratory variables were registered. In addition, we compared portable O2 by using continuous or demand flow during outdoor activities at very high altitudes. The outcomes showed no differences between production procedures (PSA or liquid oxygen) in regulating oxygen availability at AOS facilities. As a result, big-scale installations have difficulties reaching the appropriate O2 concentration due to leaks in high mobility areas. In addition, the PSA plant requires adequacy and maintenance to operate at a very high altitude. A continuous flow of 2–3 l/min of portable O2 is recommended at 5,050 m.


AIAA Journal ◽  
1967 ◽  
Vol 5 (2) ◽  
pp. 226-232 ◽  
Author(s):  
D. E. BOYLAN ◽  
J. L. POTTER
Keyword(s):  

2004 ◽  
Vol 11 (3) ◽  
pp. 197-199 ◽  
Author(s):  
Dianna Louie ◽  
Peter D Paré

Exercised-induced asthma is not due to exercise itself per se, but rather is due to cooling and/or drying of the airway because of the increased ventilation that accompanies exercise. Travel to high altitudes is accompanied by increased ventilation of cool, often dry, air, irrespective of the level of exertion, and by itself, this could represent an 'exercise' challenge for asthmatic subjects. Exercise-induced bronchoconstriction was measured at sea level and at various altitudes during a two-week trek through the Himalayas in a group of nonasthmatic and asthmatic subjects. The results of this study showed that in mild asthmatics, there was a significant reduction in peak expiratory flow at very high altitudes. Contrary to the authors' hypothesis, there was not a significant additional decrease in peak expiratory flow after exercise in the asthmatic subjects at high altitude. However, there was a significant fall in arterial oxygen saturation postexercise in the asthmatic subjects, a change that was not seen in the nonasthmatic subjects. These data suggest that asthmatic subjects develop bronchoconstriction when they go to very high altitudes, possibly via the same mechanism that causes exercise-induced asthma.


2010 ◽  
Vol 39 (2) ◽  
pp. 262-265 ◽  
Author(s):  
S. Stokes ◽  
N. S. Kalson ◽  
M. Earl ◽  
A. G. Whitehead ◽  
I. Tyrrell-Marsh ◽  
...  
Keyword(s):  

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