Maximum temperature °C Organism Time of exposure
140 Bacterial spores 5-hr immersion
170-200 Desiccated rotifers 5 min
151 Desiccated rotifers 35 min
150 Clostridium tetani 180 min
170 Aerobic bacteria, molds. actinomycetes 5 days at 6×10-9mm Hg
127 (dry) Bacteria (in activated charcoal) 60 min
110 (wet) Bacillus subtilis var. niger 400 min
120 Bacillus subtilis var. niger 400 min
141 Bacillus subtilis var. niger 70 min
160 Bacillus subtilis var. niger 15 min
180 Bacillus subtilis var. niger 2 min
188 Bacillus subtilis var. niger 1 min
120 (wet) Bacillus stearothermophilus 25 min
120 (dry) Bacillus stearothermophilus 100 min
141 Bacillus stearothermophilus 12 min
160 Bacillus stearothermophilus 2 min
166 Bacillus stearothermophilus 1 min
Table VI.—Extremes of Chemical Environmental Factors Permitting Growth or Activity

Chemical factor

Minimum

Organism

O2

0%

HeLa cells, Cephalobus,anaerobic bacteria

O3(ozone)

0%

H2

0%

H2O

Aw 0.48

Pleurococcus vulgaris

Aw 0.5

Xenopsylla cheopis(prepupae)

H2O2

0%

He

0%

CO

0%

CO2

0%

CH4

0%

CH2O

0%

CH3OH

0%

N2

0%

NO

0%

NO2

0%

N2O

0%

Ar

0%

NaCl, Na2SO4,NaHCO3

H2S

0%

H2SO4

0%

Cu++

Zn++

pH

0

Acontium velatum

Thiobacillusthioodixans

Eh

-450 mVat pH 9.5

Sulfate-reducingbacteria

Table VI.—Extremes of Chemical Environmental Factors Permitting Growth or Activity

Chemical factor

Maximum

Pressure, atm

Time, days

Organism

Activity

O2

100%

1

Plants, animals

Growth

O3(ozone)

100 ppm

5

Armillariamellea

Growth

500 ppm

5

Light emission

H2

100%

Various plants

Germination

H2O

Aw 1.0

1

Various aquaticorganisms

Growth

H2O2

0.34%

Rye

Germinationenhanced

He

100%

Wheat, rye, rice

Germination

CO

100%

Rye

Germination

80%

1.1

4

Hydrogenomonas

Growth

CO2

100%

1.1

4

Rye

Growth andgermination

CH4

100%

1.1

4

Rye

Germination

CH2O

50%

Rye

Germination

CH3OH

50%

Rye

Germination

N2

100%

.1

10

Various plants

Germination androot growth

NO

18%

.018

10

Sorghum, rice

Germination androot growth

NO2

18%

.018

10

Rye, rice

Germination androot growth

N2O

100%

1.2

4

Rye

Germination

96.5%

1.7

Rye

Germination

Tenebrio molitor

Survival

Ar

100%

1.2

2

Rye

Germination

NaCl, Na2SO4,NaHCO3

67%

Photosyntheticbacteria

Growth

H2S

0.96g/liter

Desulfovibriodesulfuricans

Growth

H2SO4

7%

Acontium velatum

Growth

Thiobacilli

Growth, reproduction

Cu++

12g/liter

Thiobacillusferrooxidans

Growth

Zn++

17g/liter

Thiobacillusferrooxidans

Growth

pH

13

Plectonemanostocorum

Growth

Nitrobacter

Growth

Nitrosomonas

Growth

Eh

850 mV at pH 3

Iron bacteria

Growth

[chapter 4]

Behavioral Biology

EFFECTS OF THE SPACE ENVIRONMENT ON BEHAVIOR

NASA was established in 1958, shortly after the Russian launching of the second Earth satellite Sputnik II, the first vehicle to carry life into orbit around the Earth. This accomplishment was preceded by the pioneering work of Henry et al. ([ref.77]), in which animals were exposed briefly to low-gravity states in Aerobee rockets. A motion-picture camera photographed the behavior of two white mice in rotating drums during this series of flights, which marked the first time that simple psychological tests were made on animals in the weightless condition. While this behavioral experiment was relatively simple, it provided the basic concepts for recent studies which involved rotation of animals during the weightless state. Subsequent flights such as Project MIA (Mouse-in-Able) reflected a preoccupation with physiologic measures (refs. [ref.78] and [ref.79]), although the flights of Baker and Able included preflight and postflight performance studies ([ref.80]). Able's behavior was recorded in detail on in-flight film, but none of the behavior was programed or under experimental control.

The first flights in which behavior or performance was explicitly programed were those of Sam and Miss Sam in flights of the Little Joe rocket with the Mercury capsule, launched from Wallops Island in 1959 and 1960 ([ref.81]). The first major space achievement in the behavioral sciences was the successful in-flight measurement of the behavior of the chimpanzee Ham in early 1961, in which the pretrained animal performed throughout the flight. The second achievement along these lines was in 1962 when the chimpanzee Enos made several orbits around Earth and performed continuously on a complex behavioral task. The tasks which the animals performed during these flights have been described in detail by Belleville et al. ([ref.82]), and the results of the in-flight performance have been presented by Henry and Mosely ([ref.83]). These early flights provided much of the technological framework on which current biological experiments on organisms during flights of extended duration are based. Due largely to the efforts of Grunzke (refs. [ref.84] and [ref.85]), the apparatus needed to sustain animals during space flight, such as zero-g watering and feeding devices, are now commonplace ([ref.86]). Advanced systems of programing stimulus presentations and recording responses, developed for Project Mercury, may now be seen in many basic research laboratories throughout the country.

Several other noteworthy advances have been made as an outgrowth of the Mercury animal flights. Immediately before the orbital flight MA-5, in which the chimpanzee Enos was employed, it was unexpectedly found that this 5-year-old animal was hypertensive. Subsequent centrifuge studies showed that its vascular responses exceeded those of a control group. Consideration of the animal's preflight experience led to speculation concerning the origin of this hypertension. An explanation of the high-blood-pressure responses detected in Enos has been pursued by Meehan et al. ([ref.87]). Persistent hypertension has been produced in other laboratory chimpanzees restrained in the same manner as those participating in space flight and exposed to demanding performance tasks, a demonstration which has important implications for prolonged manned space flight and for cardiovascular medicine in general.

Studies more directly concerned with behavior and performance have been extended from those of Project Mercury. These extensions have been in the following directions: (1) the establishment and maintenance of complex behavioral repertoires under conditions of full environmental control, (2) the refinement of behavioral techniques for assessing sensory and motor processes, and (3) the maintenance of sustained performance under conditions of long-term isolation and confinement and preliminary extension of such experimental analysis to man.