Effects of hypodynamic simulations on the skeletal system of monkeys

A research and development program was undertaken to evaluate the skeletal losses of subhuman primates in hypodynamic environments. The goals of the program are: (1) to uncover the mechanisms by which weightlessness affects the skeletal system; (2) to determine the consequences and reversibility of bone mineral losses; and (3) to acquire a body of data needed to formulate an appropriate countermeasure program for the prevention of skeletal deconditioning. Space flight experiment simulation facilities are under development and will be tested for their capability in supporting certain of the requirements for these investigations

Report of the 1st Planning Workshop for CELSS Flight Experimentation

A workshop held March 23 and 24, 1987 to establish a base upon which a CELSS flight experiment program will be developed, is summarized. The kind of information necessary for productivity assessment was determined. In addition, generic experiments necessary to gather that information were identified and prioritized. General problems of hardware and equipment were defined. The need for the hardware to provide a stress-free environment, not only for productivity, but also to make more readily identifiable disturbing mission factors, was recognized

CELSS Program Meeting

A meeting on the potential contributions of plant science to the goals of Controlled Ecological Life Support System (CELSS) research produced discussions that helped to focus on a variety of topics. In the area of volatiles and soluble organics, microbial activity, disease, and productivity, participants emphasized the need to know more about the consequences of closure for the growth of plants. Under nutrient delivery systems, the problems focus on the need to maintain a stable, optimum nutrient system. Lighting systems discussions emphasized unique methods of direct lighting and development of improved irradiation sources. Flight experiment opportunities were outlined by one speaker. Documentation of the Plant Growth Module was discussed. The last day's discussion focused on the organization of the research group to be involved in the development and use of a two to three cubic meter sealed chamber and ancillary equipment

A review of recent activities in the NASA CELSS program

A CELSS (Controlled Ecological Life Support System) is a device that utilizes photosynthetic organisms and light energy to regenerate waste materials into oxygen and food for a crew in space. The results of studies with the CELSS program suggest that a bioregenerative life support system is a useful and effective method of regenerating consumable materials for crew sustenance. The data suggests that the operation of a CELSS in space is practical if plants can be made to behave predictably in the space environment. Much of the work centers on the biological components of the CELSS system. Ways of achieving high efficiency and long term stability of all components of the system are examined. Included are explorations of the conversion of nonedible cellulose to edible materials, nitrogen fixation by biological and chemical methods, and methods of waste processing. A description is provided of the extent to which a bioregenerative life support system can meet the constraints of the space environment, and the degree is assessed to which system efficiency and stability can be increased during the next decade

Idiopathic head tremor in english bulldogs

Idiopathic head tremor (IHT) syndrome is a recognized but poorly characterized movement disorder in English bulldogs (EBs). The data analyzed were collected via a detailed online questionnaire and video recordings. Thirty-eight percent of the population demonstrated IHT. The first presentation was early in life. There was no sex or neutered status predisposition. The condition disappeared with time in 50% of the cases. The direction of the head movement was vertical or horizontal. The number of episodes per day and the duration of the episodes were greatly variable. The majority of episodes occurred at rest. Most of the episodes were unpredictable. And there was no alteration of the mental status for most dogs during the episodes. Stress has been reported as a suspected trigger factor. IHT in EBs can be considered an idiopathic paroxysmal movement disorder

Status of the isolated, threatened Valle de la Trinidad round-tailed ground squirrel, Baja California, Mexico

In 1927 Lawrence M. Huey described a new subspecies of round-tailed ground squirrel (Xerospermophilus tereticaudus apricus) from the southernmost extreme of the species, in the geographically isolated valley ‘Valle de la Trinidad’ in Baja California, Mexico. The valley has been subject to extensive agricultural conversion and severe overgrazing, which had already begun when X. t. apricus was described. Despite the loss of natural habitat, a single remaining population of this isolated subspecies was re-discovered in 2015. Acoustic surveys documented individuals at 195 of 456 points sampled. The population does not appear to be adversely affected and may actually benefit from some disturbance from cattle. The densest populations were found in open communities of large leguminous trees or shrubs, principally mesquite, which may be critical seasonal diet components. Conservation considerations are discussed

The role of fire severity, distance from fire perimeter and vegetation on post-fire recovery of small-mammal communities in chaparral

Abstract. Chaparral shrublands in southern California, US, exhibit significant biodiversity but are prone to large, intense wildfires. Debate exists regarding fuel reduction to prevent such fires in wildland areas, but the effects of these fires on fauna are not well understood. We studied whether fire severity and distance from unburned fire perimeter influenced recovery of the small-mammal community from 13 to 39 months after the large (1134.2 km 2 ) Cedar fire in San Diego County. In general, neither factor influenced small-mammal recovery. However, vegetation characteristics, distance to riparian habitat and the prevalence of rocky substrate affected recovery in species-specific patterns. This indicates the effects of fire severity and immigration from outside the fire perimeter, if they occur, do so within 1 year, whereas longerterm recovery is largely driven by previously known relationships between small mammals and habitat structure. Our results, when combined with results from other studies in southern California, suggest where human lives or infrastructure are not at risk, efforts to preserve chaparral biodiversity should focus on maintaining the native plant community. Doing so may require novel management strategies in the face of an increasing human population, ignition sources and the spread of invasive exotic plants

A comparative study of the thermal dependence of contractility in saurian skeletal muscle

1. 1. The effects of temperature on tension development in vitro were examined in the pubioischiotibialis muscle from five species of lizards.2. 2. Pronounced interspecific differences were evident in the optimal temperatures for isometric twitch tension and in the resistance to irreversible heat damage and heat rigor in the muscle.3. 3. A good correlation is evident between the thermal relations of the muscle and the extent of thermophily of the intact animal as judged by its preferred temperature and heat tolerance. Thus, adjustments at the tissue level appear to play a role in the thermal adaptations of lizards.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32101/1/0000151.pd

Modification of Experimental Protocols for a Space Shuttle Flight and Applications for the Analysis of Cytoskeletal Structures During Fertilization, Cell Division , and Development in Sea Urchin Embryos

To explore the role of microgravity on cytoskeletal organization and skeletal calcium deposition during fertilization, cell division, and early development, the sea urchin was chosen as a model developmental system. Methods were developed to employ light, immunofluorescence, and electron microscopy on cultures being prepared for flight on the Space Shuttle. For analysis of microfilaments, microtubules, centrosomes, and calcium-requiring events, our standard laboratory protocols had to be modified substantially for experimentation on the Space Shuttle. All manipulations were carried out in a closed culture chamber containing 35 ml artificial sea water as a culture fluid. Unfertilized eggs stored for 24 hours in these chambers were fertilized with sperm diluted in sea water and fixed with concentrated fixatives for final fixation in formaldehyde, taxol, EGTA, and MgCl2(exp -6)H2O for 1 cell to 16 cell stages to preserve cytoskeletal structures for simultaneous analysis with light, immunofluorescence, and electron microscopy, and 1.5 percent glutaraldehyde and 0.4 percent formaldehyde for blastula and plueus stages. The fixed samples wre maintained in chambers without degradation for up to two weeks after which the specimens were processed and analyzed with routine methods. Since complex manipulations are not possible in the closed chambers, the fertilization coat was removed from fixation using 0.5 percent freshly prepared sodium thioglycolate solution at pH 10.0 which provided reliable immunofluorescence staining for microtubules. Sperm/egg fusion, mitosis, cytokinesis, and calcium deposition during spicule formatin in early embryogenesis were found to be without artificial alterations when compared to cells fixed fresh and processed with conventional methods