Nickel-hydrogen low-Earth-orbit test program

The incorporation of nickel-hydrogen technology for low-Earth-orbit spacecraft applications requires the establishment of a data base. An extensive test program was established to provide this data base. The test program is outlined and the preliminary test programs is presented

Low-density genotype panel for both parentage verification and discovery in a multi-breed sheep population

peer-reviewedThe generally low usage of artificial insemination and single-sire mating in sheep, compounded by mob lambing (and lambing outdoors), implies that parentage assignment in sheep is challenging. The objective here was to develop a low-density panel of single nucleotide polymorphisms (SNPs) for accurate parentage verification and discovery in sheep. Of particular interest was where SNP selection was limited to only a subset of chromosomes, thereby eliminating the ability to accurately impute genome-wide denser marker panels. Data used consisted of 10,933 candidate SNPs on 9,390 purebred sheep. These data consisted of 1,876 validated genotyped sire–offspring pairs and 2,784 validated genotyped dam–offspring pairs. The SNP panels developed consisted of 87 SNPs to 500 SNPs. Parentage verification and discovery were undertaken using 1) exclusion, based on the sharing of at least one allele between candidate parent–offspring pairs, and 2) a likelihood-based approach. Based on exclusion, allowing for one discordant offspring–parent genotype, a minimum of 350 SNPs was required when the goal was to unambiguously identify the true sire or dam from all possible candidates. Results suggest that, if selecting SNPs across the entire genome, a minimum of 250 carefully selected SNPs are required to ensure that the most likely selected parent (based on the likelihood approach) was, in fact, the true parent. If restricting the SNPs to just a subset of chromosomes, the recommendation is to use at least a 300-SNP panel from at least six chromosomes, with approximately an equal number of SNPs per chromosome

Predicting mental health from the Apter Motivational Style Profile during the COVID-19 pandemic – the importance of planfulness and goal orientation

The research reported here examines the utility of Reversal Theory variables, amongst others, as predictors of mental health during the 2020-21 covid pandemic. 135 participants completed an author-generated ‘Lockdown Questionnaire”, The Apter Motivational Style Profile for research (AMSP-R), the Multidimensional Mortality Awareness Measure, and questions about demographic factors. Dependent variables were three self-report questionnaires measuring eudaimonic well-being, depression, and health anxiety. AMSP-R variables were found to be bivariately associated with the dependent variables. Results from multiple regression analyses between significant bivariate correlates and the three dependent variables notably showed that telic AMSP scores emerged as the leading independent predictor of eudaimonic well-being. Other predictors of outcome variables included mortality fearfulness, disengagement and acceptance, diffculty managing health conditions during lockdown, physical activity, highest level of educational attainment, and political orientation. It can be inferred from the study’s main finding that those during the pandemic who adopted a goal-oriented and planful mindset appear to have been more resilient during this time of chronic adversity than those who did not. Conversely, it is plausible that happier people tend to be able to engage in greater goal activity. Both explanations, however, are not mutually exclusive. The finding has implications for ongoing public health messaging to help people manage their mental health during the continuing pandemic

Survival of fossils under extreme shocks induced by hypervelocity impacts

Experimental data are shown for survival of fossilized diatoms undergoing shocks in the GPa range. The results were obtained from hypervelocity impact experiments which fired fossilized diatoms frozen in ice into water targets. After the shots, the material recovered from the target water was inspected for diatom fossils. Nine shots were carried out, at speeds from 0.388 to 5.34?km?s?1, corresponding to mean peak pressures of 0.2–19?GPa. In all cases, fragmented fossilized diatoms were recovered, but both the mean and the maximum fragment size decreased with increasing impact speed and hence peak pressure. Examples of intact diatoms were found after the impacts, even in some of the higher speed shots, but their frequency and size decreased significantly at the higher speeds. This is the first demonstration that fossils can survive and be transferred from projectile to target in hypervelocity impacts, implying that it is possible that, as suggested by other authors, terrestrial rocks ejected from the Earth by giant impacts from space, and which then strike the Moon, may successfully transfer terrestrial fossils to the Moon