Social distancing as a public good under the COVID-19 pandemic.

OBJECTIVES: The purpose of this study is to show that social distancing is a public good under the COVID-19 pandemic. STUDY DESIGN: We apply economic theory to analyse a cross-sectional survey. METHODS: Economic theory is complemented with empirical evidence. An online survey of those aged 30-49 years in Japan (n = 2177) was conducted between April 28 and May 7. Respondents were selected by quota sampling with regard to age group, gender and prefecture of residence. Our main figure shows the proportion of people who increased/did not change/decreased social distancing, relative to the level of altruism and sensitivity to public shaming. The results of OLS and logit models are shown in Supplementary Materials. RESULTS: Social distancing is a public good under the COVID-19 pandemic for which the free-rider problem is particularly severe. Altruism and social norms are crucial factors in overcoming this problem. Using an original survey, we show that people with higher altruistic concerns and sensitivity to shaming are more likely to follow social distancing measures. CONCLUSIONS: Altruism and social norms are important for reducing the economic cost of the pandemic.

The application of AFLP fingerprinting to construct a YAC contig containing ADH2 and MTP on sheep chromosome 6.

The low density of genetic markers on livestock maps limits progress in positional cloning projects. We demonstrate a strategy of combining comparative mapping with AFLP fingerprinting to develop physical maps in a defined region of the sheep genome. Sequence tagged sites for alcohol dehydrogenase 2 (ADH2) and microsomal triglyceride transfer protein (MTP) were developed and used to screen a sheep yeast artificial chromosome (YAC) library. Nine YACs were identified containing the microsatellite marker BM1329 and either ADH2 or MTP. Additional markers in the region were not available, and AFLP analysis was developed to identify sheep-specific bands within the YACs to determine their degree of overlap. Fourteen bands common to more than one YAC were analysed and provided the markers necessary to develop a YAC contig containing the three STS markers. One YAC (yac260B5) containing all three markers (ADH2, MTP, and BM1329) was mapped to sheep chromosome 6q1.6-->q1.8 by FISH analysis.

Design of libraries to explore receptor sites.

Despite rapid progress in both combinatorial chemistry and high-throughput screening, the number of molecules that could potentially be made and tested for biological activity still far exceeds the capacity for synthesis or screening. Consequently, it is potentially valuable to select and synthesize sublibraries that contain rationally selected subsets. When the structure of the protein receptor site is known, this may be used to impose restrictions of the selection on molecules. This paper describes a method for rapid analysis of large virtual libraries to select a subset that can exhibit at least one conformer which wil interact strongly with the receptor and fit within the receptor site.

Inter- and intraspecific polymorphism at chloroplast SSR loci and the inheritance of plastids in Pinus radiata D. Don.

DNA sequence analysis of chloroplast genomes has revealed many short nucleotide repeats analogous to nuclear microsatellites, or simple sequence repeats (SSRs). We designed PCR primers flanking five of these regions identified in the chloroplast sequence from Pinus thunbergii and tested them for amplification in Pinus radiata, P. elliotii, P. taeda, P. strobus, Pseudotsuga menziesii, Cupressus macrocarpa, four New Zealand native conifer species (Podocarpus totara, Podocarpus hallii, Podocarpus nivalis, Agathis australis), and four angiosperms (Vitex lucens, Nestegis cunninghamii, Actinidia chinensis, and Arabidopsis thaliana). A PCR product in the expected size range was amplified from all species and interspecific polymorphism was detected at all five loci. Intraspecific polymorphism was detected in P. radiata with four of the five primer pairs. One of these polymorphic chloroplast SSR (cpSSR) was then used to determine the inheritance of chloroplasts in 206 progeny from four control-pollinated, full-sibling P. radiata families. Approximately 99% of the progeny had the cpSSR variant of the pollen parent indicating that in Pinus radiata, like most other conifers, chloroplasts are typically inherited from the paternal parent. These results suggest that polymorphic chloroplast SSRs will be a valuable tool for studying chloroplast diversity, cyto-nuclear disequilibrium, and plastid inheritance in a range of species, and for the analysis of gene flow via pollen and paternity in species with paternal transmission of chloroplasts.