2,000 Pound High Altitude Low Opening Ballistic Parachute System Development

AbstractAerobic performance is tied to fitness as it influences an animal’s ability to find food, escape predators, or survive extreme conditions. At high altitude, where low O2 availability and persistent cold prevail, maximum metabolic heat production (thermogenesis) is an aerobic performance trait that is intimately linked to survival. Understanding how thermogenesis evolves to enhance survival at high altitude will yield insight into the links between physiology, performance, and fitness. Recent work in deer mice (Peromyscus maniculatus) has shown that adult mice native to high-altitude have higher thermogenic capacities under hypoxia compared to lowland conspecifics, but developing high-altitude pups delay the onset of thermogenesis. This suggests that natural selection on thermogenic capacity varies across life stages. To determine the mechanistic cause of this ontogenetic delay, we analyzed the transcriptomes of thermo-effector organs – brown adipose tissue and skeletal muscle – in developing deer mice native to low- and high-altitude. We demonstrate that the developmental delay in thermogenesis is associated with adaptive shifts in the expression of genes involved in nervous system development, fuel/O2 supply, and oxidative metabolism gene pathways. Our results demonstrate that selection has modified the developmental trajectory of the thermoregulatory system at high altitude and has done so by acting on the regulatory systems that control the maturation of thermo-effector tissues. We suggest that the cold and hypoxic conditions of high altitude may force a resource allocation trade-off, whereby limited energy is allocated to developmental processes such as growth, versus active thermogenesis during early development.

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Low Altitude High Speed Cargo Parachute system development - A status report

10.2514/6.1991-880 ◽

1991 ◽

Author(s):

W. SUNDBERG ◽

THOMAS ALSBROOKS ◽

KENNETH RONQUILLO ◽

JAMES SADECK ◽

CALVIN LEE

Keyword(s):

High Speed ◽

System Development ◽

Status Report ◽

Parachute System ◽

Low Altitude

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Payload system development for high altitude balloon

2014 IEEE/SICE International Symposium on System Integration ◽

10.1109/sii.2014.7028129 ◽

2014 ◽

Cited By ~ 3

Author(s):

Haklin Kimm

Keyword(s):

High Altitude ◽

System Development

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Adaptive Shifts in Gene Regulation Underlie a Developmental Delay in Thermogenesis in High-Altitude Deer Mice

Molecular Biology and Evolution ◽

10.1093/molbev/msaa086 ◽

2020 ◽

Vol 37 (8) ◽

pp. 2309-2321 ◽

Cited By ~ 3

Author(s):

Jonathan P Velotta ◽

Cayleih E Robertson ◽

Rena M Schweizer ◽

Grant B McClelland ◽

Zachary A Cheviron

Keyword(s):

High Altitude ◽

Developmental Delay ◽

System Development ◽

Nervous System Development ◽

Developmental Trajectory ◽

Aerobic Performance ◽

Deer Mice ◽

Adult Mice ◽

Brown Adipose ◽

Adaptive Shifts

Abstract Aerobic performance is tied to fitness as it influences an animal’s ability to find food, escape predators, or survive extreme conditions. At high altitude, where low O2 availability and persistent cold prevail, maximum metabolic heat production (thermogenesis) is an aerobic performance trait that is closely linked to survival. Understanding how thermogenesis evolves to enhance survival at high altitude will yield insight into the links between physiology, performance, and fitness. Recent work in deer mice (Peromyscus maniculatus) has shown that adult mice native to high altitude have higher thermogenic capacities under hypoxia compared with lowland conspecifics, but that developing high-altitude pups delay the onset of thermogenesis. This finding suggests that natural selection on thermogenic capacity varies across life stages. To determine the mechanistic cause of this ontogenetic delay, we analyzed the transcriptomes of thermoeffector organs—brown adipose tissue and skeletal muscle—in developing deer mice native to low and high altitude. We demonstrate that the developmental delay in thermogenesis is associated with adaptive shifts in the expression of genes involved in nervous system development, fuel/O2 supply, and oxidative metabolism pathways. Our results demonstrate that selection has modified the developmental trajectory of the thermoregulatory system at high altitude and has done so by acting on the regulatory systems that control the maturation of thermoeffector tissues. We suggest that the cold and hypoxic conditions of high altitude force a resource allocation tradeoff, whereby limited energy is allocated to developmental processes such as growth, versus active thermogenesis, during early development.

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Contrast of Filament Bright Rims

International Astronomical Union Colloquium ◽

10.1017/s0252921100025628 ◽

1994 ◽

Vol 144 ◽

pp. 365-367

Author(s):

E. V. Kononovich ◽

O. B. Smirnova ◽

P. Heinzel ◽

P. Kotrč

Keyword(s):

High Altitude ◽

Line Profile ◽

Line Center ◽

Magnetic Structures ◽

The Mean

AbstractThe Hα filtergrams obtained at Tjan-Shan High Altitude Observatory near Alma-Ata (Moscow University Station) were measured in order to specify the bright rims contrast at different points along the line profile (0.0; ± 0.25; ± 0.5; ± 0.75 and ± 1.0 Å). The mean contrast value in the line center is about 25 percent. The bright rims interpretation as the bases of magnetic structures supporting the filaments is suggested.

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Clean Electron Microscope Substrate Films Used for Micrometeorite Collection and Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061847 ◽

1967 ◽

Vol 25 ◽

pp. 366-367

Author(s):

D. M. Davies ◽

R. Kemner ◽

E. F. Fullam

Keyword(s):

Thin Film ◽

Electron Microscope ◽

High Altitude ◽

Amyl Acetate ◽

Temperature Variations ◽

Film Forming ◽

Film Specimen ◽

Particulate Contaminants

All serious electron microscopists at one time or another have been concerned with the cleanliness and freedom from artifacts of thin film specimen support substrates. This is particularly important where there are relatively few particles of a sample to be found for study, as in the case of micrometeorite collections. For the deposition of such celestial garbage through the use of balloons, rockets, and aircraft, the thin film substrates must have not only all the attributes necessary for use in the electron microscope, but also be able to withstand rather wide temperature variations at high altitude, vibration and shock inherent in the collection vehicle's operation and occasionally an unscheduled violent landing.Nitrocellulose has been selected as a film forming material that meets these requirements yet lends itself to a relatively simple clean-up procedure to remove particulate contaminants. A 1% nitrocellulose solution is prepared by dissolving “Parlodion” in redistilled amyl acetate from which all moisture has been removed.

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