Laying Eggs at High Altitude

Physiology ◽  
1988 ◽  
Vol 3 (2) ◽  
pp. 69-71 ◽  
Author(s):  
CC Monge ◽  
F Leon-Velarde ◽  
G Gomez de la Torre
Keyword(s):  
High Altitude ◽  
Water Loss ◽  
Oxygen Supply ◽  
The Other ◽  
High Altitudes ◽  
High Mountains ◽  
The One ◽  
Very High

The hypoxic and dry environment of the high mountains seems to select eggshells with porosities appropriate for the altitudinal level. At moderate altitudes, the conservation of water takes precedence over the oxygen-supply gradient. At very high altitudes there is a compromise between reducing water loss on the one hand and the defense of the oxygen supply to the embryo on the other.

scholarly journals Comparison Between Pressure Swing Adsorption and Liquid Oxygen Enrichment Techniques in the Atacama Large Millimeter/Submillimeter Array Facility at the Chajnantor Plateau (5,050 m)

2021 ◽  
Vol 12 ◽  
Author(s):  
Ivan Lopez ◽  
Reinaldo Aravena ◽  
Daniel Soza ◽  
Alicia Morales ◽  
Silvia Riquelme ◽  
...  
Keyword(s):  
High Altitude ◽  
Pressure Swing Adsorption ◽  
Large Scale ◽  
High Mobility ◽  
Oxygen Enrichment ◽  
Oxygen Availability ◽  
Liquid Oxygen ◽  
High Altitudes ◽  
Pressure Swing ◽  
Very High

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.

Bit Swap Established on EOC for VDSL

2014 ◽  
Vol 513-517 ◽  
pp. 1170-1175
Author(s):  
Chen En Liu ◽  
Ping Li
Keyword(s):  
Rapid Development ◽  
The Other ◽  
Test Results ◽  
Digital Subscriber Line ◽  
Crosstalk Noise ◽  
Line System ◽  
Subscriber Line ◽  
High Bit Rate ◽  
The One ◽  
Very High

With the rapid development of VDSL (Very high-bit-rate Digital Subscriber Line) system, not all the tones have the same margin. In order to cope with the slowly-changing channel, Bit Swap is utilized to swap the tone pairs: the one has a high margin while the other one has a relatively low margin. Although the Bit Swap has been proposed before, there is no Bit Swap established on EOC and the proposed scheme also implements coarse and fine SNR margin tuning. The paper presents the architecture and process of Bit Swap based on EOC and also proposes the method to adjust the margin for tones calculated to be swapped. After thoroughly tested, the test results show that the proposed scheme functions well. Compared with the scheme without Bit Swap, it greatly improves the performance against crosstalk noise and can reduce the RS errors to zero.

VIII. On the structure and development of the skull in the ostrich tribe

1866 ◽  
Vol 156 ◽  
pp. 113-183 ◽  
Keyword(s):  
The Other ◽  
The One ◽  
High Degree ◽  
Very High

T he present paper is intended to be the first of a series on the Anatomy of the Vertebrate Skull; and I have chosen the cranium and face of the Ostriches as a startingpoint, principally because of the mid position of these birds in the vertebrate subkingdom, and, in some degree also, because of their generalized character. Indeed, to any one familiar, on the one hand, with the structure of the skull in the higher mammalian types, and on the other with that of the osseous fishes, the skull of an Ostrich is interesting and important in a very high degree; serving, at it does, as a key to open up the meaning of parts so extremely unlike as the true homologues in the Fish and in the Mammal often are. And further, whilst aiding the anatomist in revealing the true morphological counterparts in the highest, as compared with the lowest types, the skull of an ostrich does also form a link of the utmost value for connecting together that of a cold-blooded and that of a warm-blooded creature.

scholarly journals Illustrations of the viscous theory of glaciers

1851 ◽  
Vol 5 ◽  
pp. 603-604 ◽  
Keyword(s):  
Solid Body ◽  
Average Velocity ◽  
Freezing Point ◽  
Plastic Material ◽  
Fluid Pressure ◽  
The Other ◽  
High Mountains ◽  
Appreciable Change ◽  
The One ◽  
Glacier Motion

Part III. The author inquires, in this part of his paper, into the motion of those comparatively small isolated glacial masses, reposing in the cavities of high mountains or on cols , and called by De Saussure glaciers of the second order . A glacier of this description in the neighbourhood of the Hospice du Simplon, lodged in a niche on the northern face of the Schœnhorn, immediately behind the Hospice, and at an elevation of about 8000 feet above the sea, was selected for observation. The average velocity of its descent was found to be about one inch and a half in twenty-four hours : those parts in which the slope was 20° moving with a velocity about one-third greater than those in which the slope was 10°. The author next enters into general views on the annual motion of glaciers, and on the influence of seasons ; and gives tabular details of the observations made with reference to these questions at two stations ; the one on the Glacier des Bossons, and the other at the Glacier des Bois, which is the outlet of the Mer de Glace towards the valley of Chamouni. In both these glaciers, the motion in summer exceeds that in winter in a greater proportion as the station is lower, and consequently exposed to more violent alternations of heat and cold. He also found that the variations of velocity due to season are greatest where the variations in the temperature of the air are greatest, as in the lower valleys ; excepting that variations of temperature below the freezing-point produce scarcely any appreciable change in the rate of motion of the ice. He concludes with some general illustrations of the plastic or viscous theory of glacier motion. A glacier, he contends, is not a mass of fragments or parallelopipedons ; neither is it a rigidly solid body ; and although it may be extensively intersected by crevices, these “ crevasses” are com­paratively superficial, and do not disturb the general continuity of the mass in which they occur. The water contained in these crevices is only the principal vehicle of the force which acts upon it : and the irresistible energy with which the whole icy mass descends from hour to hour with a slow but continuous motion bespeaks of itself the operation of a fluid pressure acting on a ductile or plastic material.

Première of films arranged by the Shell International Petroleum Company

1961 ◽  
Vol 16 (1) ◽  
pp. 93-94
Keyword(s):  
Natural Science ◽  
Royal Society ◽  
The Other ◽  
High Quality ◽  
Natural Knowledge ◽  
Royal Dutch Shell ◽  
The One ◽  
Petroleum Company ◽  
Very High

On the afternoon of Friday 22 July, a premiere of films was given at the Royal Festival Hall and was followed by a Reception at Tea when Mr F. J. Stephens acted as host for the Royal Dutch/Shell Group of Companies. The programme was introduced by Sir Cyril Flinshelwood, President of the Royal Society, who said: . ‘In the Charter of the Royal Society the improvement of natural knowledge is coupled with that of the useful arts. Now the tradition fortunately exists in this country of good relations between the great industries on the one hand and the cultivators of natural science on the other: or I would prefer to say the very nebulous line that there is between these two branches of activity is evidence of the fact that this part of the Charter has in fact not been ignored. That the Shell Group of Companies, one of the greatest and most important, has made the extremely generous gesture of preparing the very splendid film that you will presently see in honour of the Tercentenary of the Royal Society proves that the tradition that I have spoken of is alive and vigorous. ‘You will presently agree that the film also demonstrates the very high quality of the Film Unit which the Company has maintained for, I understand, something over a quarter of a century.

scholarly journals Religious involvement of University of Pretoria campus students. Results of an enquiry

2004 ◽  
Vol 25 (1) ◽  
pp. 102-124
Author(s):  
J J Kritzinger
Keyword(s):  
Religious Involvement ◽  
The Other ◽  
Full Time ◽  
Moral Issues ◽  
Large Sample ◽  
Main Campus ◽  
University Of Pretoria ◽  
The One ◽  
Very High

In a large sample of full-time University of Pretoria main campus students it was  found  that  a very high percentage of all the students reported an affiliation to religious bodies. They also generally regarded themselves as religious.  Many also regularly took part in the religious programmes. Quite a rosy statistical picture could be drawn. The one worrying result is the  chasm  which  shows between what the students regard as their religious organisation’s views on certain moral issues, on  the one hand, and their own lifestyles, on the other.

High Altitude Observations at Sea

1951 ◽  
Vol 4 (02) ◽  
pp. 165-166
Author(s):  
A. N. Black
Keyword(s):  
High Altitude ◽  
Maximum Error ◽  
Sufficient Accuracy ◽  
Rate Of Change ◽  
Zenith Distance ◽  
The Sun ◽  
High Altitudes ◽  
Short Period ◽  
Very High

It is difficult to get satisfactory noon observations when the zenith distance is very small, because the Sun is rapidly changing in azimuth, the sextant must be swung through a wide arc of the horizon, and the Sun only dwells at the highest altitude for a very short period. To avoid these difficulties it is suggested that, instead of trying to measure the altitude of the Sun, one should measure its distance from a point on the horizon in a known azimuth. To make this measurement the Sun is brought down to the required point on the horizon, tilting the sextant as necessary; we shall distinguish this type of observation from the normal one, made with the sextant vertical, by calling the angle so obtained thehorizon distance. At normal altitudes this method, however sound in theory, breaks down because one cannot measure the azimuth with sufficient accuracy. However, at very high altitudes the rate of change of horizon distance with change of azimuth of the point from which the distance is measured becomes so small that it is not necessary to know the azimuth with such precision. In fact, at a zenith distance of 1°, the largest we shall consider here, the greatest error caused by an error of 1° in the azimuth is l″, and for smaller zenith distances the maximum error is proportionately less.

scholarly journals De Traditionele Hofhouding Bij de bin Kanyok van Zaire

Afrika Focus ◽  
1989 ◽  
Vol 5 (1-2) ◽  
pp. 21-63
Author(s):  
Patrick Wymeersch
Keyword(s):  
Political System ◽  
Colonial Period ◽  
The Other ◽  
Political Organization ◽  
The Political ◽  
Royal Family ◽  
Royal Court ◽  
The One ◽  
High Degree ◽  
Very High

The Traditional Royal Court Among the bin Kanyok of Zaire This description represents what was more or less an ideal conception of political organization and kingship before the colonial period. If the traditional systems of ruling still remain, the material symbolism of kingship disappeared mostly in the scene of daily life in the king’s large capital. Looking at the political organization, two seemingly contradictory features emerge. On the one hand, there are the politically quasi-independent lineages living in the villages. The chief or eldest of a lineage is at the same time chief of the whole village. On the other hand, there is the formal political organization, build on a hierarchical model and imposed from the top. This political system is notable for its very high degree of centralization, and especially for the strong authority and power of the divine king. For the purpose of government, the kingdom is divided into sub-districts, containing several villages of an area, districts and provinces. They all depend, in hierarchy,from the capital. The capital accommodates most of the members of the royal family, numerous wives and children from the king and the ministers. The king’s compound, standing in the middle of the capital, is surrounded by a fence. This compound is divided into four specific parts and contains several houses and the palace of the king. On both sides of the royal compound, there is a main street where the ministers and their families live. The king’s person is surrounded by a number of taboos. No one could see him eat in his private kitchen. The principal problem in the political organization is that of the administering the rest of the Kanyok empire, of keeping as a political unit a population divided into autonomous lineages. The model that is followed is, in general, typical of the kingdoms of the southern savanna belt of Zaire. Therefore the structure is pyramidal: the king at the apex delegates his power and authority to the governors. Their position duplicates that of the king, but on a smaller scale. The king is assisted by his ministers to whom he assigned highly specific functions. The king still remains the main focus for all the Bin Kanyok.

scholarly journals Gaia DR2 view of the Lupus V–VI clouds: The candidate diskless young stellar objects are mainly background contaminants

2018 ◽  
Vol 615 ◽  
pp. L1 ◽  
Author(s):  
C. F. Manara ◽  
T. Prusti ◽  
F. Comeron ◽  
R. Mor ◽  
J. M. Alcalá ◽  
...  
Keyword(s):  
The Other ◽  
Young Stellar Objects ◽  
Galactic Latitude ◽  
Stellar Objects ◽  
Star Forming ◽  
Star Forming Regions ◽  
The One ◽  
Gaia Dr2 ◽  
Very High ◽  
Infrared Data

Extensive surveys of star-forming regions with Spitzer have revealed populations of disk-bearing young stellar objects. These have provided crucial constraints, such as the timescale of dispersal of protoplanetary disks, obtained by carefully combining infrared data with spectroscopic or X-ray data. While observations in various regions agree with the general trend of decreasing disk fraction with age, the Lupus V and VI regions appeared to have been at odds, having an extremely low disk fraction. Here we show, using the recent Gaia data release 2 (DR2), that these extremely low disk fractions are actually due to a very high contamination by background giants. Out of the 83 candidate young stellar objects (YSOs) in these clouds observed by Gaia, only five have distances of ~150 pc, similar to YSOs in the other Lupus clouds, and have similar proper motions to other members in this star-forming complex. Of these five targets, four have optically thick (Class II) disks. On the one hand, this result resolves the conundrum of the puzzling low disk fraction in these clouds, while, on the other hand, it further clarifies the need to confirm the Spitzer selected diskless population with other tracers, especially in regions at low galactic latitude like Lupus V and VI. The use of Gaia astrometry is now an independent and reliable way to further assess the membership of candidate YSOs in these, and potentially other, star-forming regions.

scholarly journals Chronic Granulocytic Leukemia and the Philadelphia Chromosome

Blood ◽  
1963 ◽  
Vol 21 (2) ◽  
pp. 183-196 ◽  
Author(s):  
P. H. FITZGERALD ◽  
ANGELA ADAMS ◽  
FREDERICK W. GUNZ
Keyword(s):  
Complete Remission ◽  
Acute Phase ◽  
Chromosome Abnormality ◽  
Philadelphia Chromosome ◽  
The Other ◽  
Direct Examination ◽  
Chronic Granulocytic Leukemia ◽  
The One ◽  
Granulocytic Leukemia ◽  
Very High

Abstract Twelve patients with chronic granulocytic leukemia were examined for the presence of the Ph1 chromosome abnormality at various stages of their disease. The abnormality was demonstrated either in the blood or marrow of all patients. Patients in relapse showed very high numbers of Ph1-positive mitoses in both blood and marrow; those in remission showed relatively few or no positives in the blood but sizeable numbers in the marrow. There was a positive correlation between the degrees of abnormality of blood and marrow on the one hand, and the percentage of Ph1-positive mitoses on the other. Direct examination of the marrow for the demonstration of the Ph1 appeared of particular value in the acute phase of chronic granulocytic leukemia. It seemed likely that therapy depressed the number of abnormal (Ph1-positive) mitoses. There was, however, no evidence that these ever disappeared from the marrow, even in complete remission. The findings presented and those in the literature did not make it possible to decide in what way the Ph1 chromosome abnormality is related to the onset of leukemia.

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