686 research outputs found
Implementation of R & QA practices in Research and Development programs
DOE has established a number of broad programs aimed at reducing fuel consumption. Several programs address the R&D of ground transportation propulsion alternatives to the conventional spark-ignition engine. NASA Lewis is responsible for managing the effort between the Government and industry teams involving American and foreign companies. Thus, existing NASA SR&QA procedure were modified/adapted to these R&D programs and implemented to assure that the test hardware design intent was met, the hardware was not hazardous to personnel, it would demonstrate reliable operation, and it would help establish the future R&D quality assurance and maintainability requirements. This successful low-cost approach might be applicable to other similar projects
System safety in Stirling engine development
The DOE/NASA Stirling Engine Project Office has required that contractors make safety considerations an integral part of all phases of the Stirling engine development program. As an integral part of each engine design subtask, analyses are evolved to determine possible modes of failure. The accepted system safety analysis techniques (Fault Tree, FMEA, Hazards Analysis, etc.) are applied in various degrees of extent at the system, subsystem and component levels. The primary objectives are to identify critical failure areas, to enable removal of susceptibility to such failures or their effects from the system and to minimize risk
Handbook of cleaning requirements, procedures, and verification techniques for oxygen systems
Oxygen system cleaning specifications have been drawn from twenty-three government and industrial sources. Cleaning processes for meeting these specifications and recommended postcleaning inspection procedures are compiled in handbook. Microfiche supplement of pertinent pages of listed references is included
Sac1p mediates the adenosine triphosphate transport into yeast endoplasmic reticulum that is required for protein translocation.
Protein translocation into the yeast endoplasmic reticulum requires the transport of ATP into the lumen of this organelle. Microsomal ATP transport activity was reconstituted into proteoliposomes to characterize and identify the transporter protein. A polypeptide was purified whose partial amino acid sequence demonstrated its identity to the product of the SAC1 gene. Accordingly, microsomal membranes isolated from strains harboring a deletion in the SAC1 gene (sac1 delta) were found to be deficient in ATP-transporting activity as well as severely compromised in their ability to translocate nascent prepro-alpha-factor and preprocarboxypeptidase Y. Proteins isolated from the microsomal membranes of a sac1 delta strain were incapable of stimulating ATP transport when reconstituted into the in vitro assay system. When immunopurified to homogeneity and incorporated into artificial lipid vesicles, Sac1p was shown to reconstitute ATP transport activity. Consistent with the requirement for ATP in the lumen of the ER to achieve the correct folding of secretory proteins, the sac1 delta strain was shown to have a severe defect in transport of procarboxypeptidase Y out of the ER and into the Golgi complex in vivo. The collective data indicate an intimate role for Sac1p in the transport of ATP into the ER lumen
Examination of Scavenging Associated with Wolves
Forensic anthropologists often confront external influences on a body, whether they are human, animal, or environmental. One of the major and most common confounding factors for forensic anthropologists is animal scavenging and the damage this inflicts on the skeleton. The types of scavengers present vary from region to region, and in the Northwest, large carnivores such as bears, mountain lions, and canids are abundant. These types of carnivores can not only inflict incredible trauma to a skeleton, they can also disperse the remains over very large areas, making it difficult for forensic teams to recover all of the skeletal elements for identification. Research has been done on tooth mark and bite mark patterns so that scavengers can be differentiated, but there is very little research on how an animal’s behavior may affect the context of a deposition site. The purpose of this research is to closely examine the scavenging patterns of a large carnivore common in the Northwest, wolves, by presenting a carcass to a captive wolf pack and visually observing their behavior, especially scavenging behaviors such as targeted areas of the body, the dispersal of remains, and caching. The hypothesis is that if a scavenger is able to be identified at the scene, then based on the animal’s typical scavenging behavior, forensic professionals can narrow the parameters of their search and hopefully recover more skeletal elements that could be crucial to reconstructing the context of the scene. The results of this study reject the null hypothesis that scavengers cannot by distinguished from one another based on their patterns of behavior when encountering a carcass. The scavenging behavior of a wolf pack varies significantly from that of bears or mountain lions, given the differences between pack hunters and solitary hunters. It will be considerably harder to distinguish between wolves and other canids, especially coyotes, although differences in tooth and jaw morphology may assist with this
The Saccharomyces cerevisiae SEC14 Gene Encodes a Cytosolic Factor That Is Required for Transport of Secretory Proteins from the Yeast Golgi Complex
We have obtained and characterized a genomic clone of SEC14, a Saccharomyces cerevisiae gene whose product is required for export of yeast secretory proteins from the Golgi complex. Gene disruption experiments indicated that SEC14 is an essential gene for yeast vegetative growth. Nucleotide sequence analysis revealed the presence of an intron within the SEC14 structural gene, and predicted the synthesis of a hydrophilic polypeptide of 35 kD in molecular mass. In confirmation, immunoprecipitation experiments demonstrated SEC14p to be an unglycosylated polypeptide, with an apparent molecular mass of some 37 kD, that behaved predominantly as a cytosolic protein in subcellular fractionation experiments. These data were consistent with the notion that SEC14p is a cytosolic factor that promotes protein export from yeast Golgi. Additional radiolabeling experiments also revealed the presence of SEC14p-related polypeptides in extracts prepared from the yeasts Kluyveromyces lactis and Schizosaccharomyces pombe. Furthermore, the K. lactis SEC14p was able to functionally complement S. cerevisiae sec14ts defects. These data suggested a degree of conservation of SEC14p structure and function in these yeasts species
Lightning accommodation systems for wind turbine generator safety
The wind turbine safety program identifies the naturally occurring lightning phenomenon as a hazard with the potential to cause loss of program objectives, injure personnel, damage system instrumentation, structure or support equipment and facilities. Several candidate methods of lightning accommodation for each blade were designed, analyzed, and tested by submitting sample blade sections to simulated lightning. Lightning accommodation systems for composite blades were individually developed. Their effectiveness was evaluated by submitting the systems to simulated lightning strikes. The test data were analyzed and system designs were reviewed on the basis of the analysis. This activity is directed at defining design and procedural constraints, requirements for safety devices and warning methods, special procedures, protective equipment and personnel training
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