The supernova rate and delay time distribution in the Magellanic Clouds

We use the supernova remnants (SNRs) in the Magellanic Clouds (MCs) as a supernova (SN) survey, "conducted" over tens of kyr, from which we derive the current SN rate, and the SN delay time distribution (DTD), i.e., the SN rate vs. time that would follow a hypothetical brief burst of a star formation. In Badenes, Maoz, & Draine (2010) we have compiled a list of 77 SNRs in the MCS, and argued it is a fairly complete record of the SNRs in the Sedov phase of their expansions. We recover the DTD by comparing the numbers of SNRs observed in small individual "cells" in these galaxies to the star-formation histories of each cell, as calculated from resolved stellar populations by Harris & Zaritsky. The visibility times of SNRs are the Sedov-phase lifetimes, which depend on the local ambient densities. The local densities are estimated from HI emission, from an inverse Schmidt law based on either Halpha flux or on the resolved star-formation rate, and from combinations of these tracers. In the DTD, we detect "prompt" type-Ia SNe (that explode within 330 Myr of star formation) at >99% confidence level (c.l.). The best fit for the number of prompt SNe-Ia per stellar mass formed is (2.7-11.0) x 10^{-3} /Msun, depending on the density tracer used. The 95% c.l. range for a "delayed" SN Ia component (from 330 Myr to a Hubble time) is < 1.6 x 10^{-13} SN/yr/Msun, consistent with rate measurements in old populations. The current total (core-collapse+Ia) SN rate in the MCs is 2.5-4.6 SNe per millenium (68% c.l.+systematics), or 1.7-3.1 SNuM [SNe/100 yr/10^{10}Msun], in agreement with the historical record and with rates measured in other dwarf irregulars. Conversely, assuming the SNRs are in free expansion, rather than in their Sedov phase, would impose on the SNRs a maximum age of 6 kyr, and would imply a MC SN rate per unit mass that is 5 times higher than in any type of galaxy.Comment: MNRAS, in pres

Integrative Annotation of 21,037 Human Genes Validated by Full-Length cDNA Clones

The human genome sequence defines our inherent biological potential; the realization of the biology encoded therein requires knowledge of the function of each gene. Currently, our knowledge in this area is still limited. Several lines of investigation have been used to elucidate the structure and function of the genes in the human genome. Even so, gene prediction remains a difficult task, as the varieties of transcripts of a gene may vary to a great extent. We thus performed an exhaustive integrative characterization of 41,118 full-length cDNAs that capture the gene transcripts as complete functional cassettes, providing an unequivocal report of structural and functional diversity at the gene level. Our international collaboration has validated 21,037 human gene candidates by analysis of high-quality full-length cDNA clones through curation using unified criteria. This led to the identification of 5,155 new gene candidates. It also manifested the most reliable way to control the quality of the cDNA clones. We have developed a human gene database, called the H-Invitational Database (H-InvDB; http://www.h-invitational.jp/). It provides the following: integrative annotation of human genes, description of gene structures, details of novel alternative splicing isoforms, non-protein-coding RNAs, functional domains, subcellular localizations, metabolic pathways, predictions of protein three-dimensional structure, mapping of known single nucleotide polymorphisms (SNPs), identification of polymorphic microsatellite repeats within human genes, and comparative results with mouse full-length cDNAs. The H-InvDB analysis has shown that up to 4% of the human genome sequence (National Center for Biotechnology Information build 34 assembly) may contain misassembled or missing regions. We found that 6.5% of the human gene candidates (1,377 loci) did not have a good protein-coding open reading frame, of which 296 loci are strong candidates for non-protein-coding RNA genes. In addition, among 72,027 uniquely mapped SNPs and insertions/deletions localized within human genes, 13,215 nonsynonymous SNPs, 315 nonsense SNPs, and 452 indels occurred in coding regions. Together with 25 polymorphic microsatellite repeats present in coding regions, they may alter protein structure, causing phenotypic effects or resulting in disease. The H-InvDB platform represents a substantial contribution to resources needed for the exploration of human biology and pathology

Studies of Isonymy and Inbreeding in Japan

In 1972, when the population of Japan was about 100 million, there were 120,000 surnames. Some features of this enormous list of names are: the 100 most common names make up 37% of the population and 5000 names include 92% ; the three most common names in order are Sato, Suzuki, and Takahasi; a name has an average of two homonyms because Japanese surnames usually have two or three Chinese symbols and a sound can often by symbolized in more than one way; 90% of the surnames can be expressed by combinations of 300 Chinese letters; altogether, some 3500 Chinese letters are in use for Japanese surnames; and an average of two or three random pairs per thousand share the same surname.A brief history of surnames in Japan is also included for those who do not have access to Japanese references. Remote ancestry that cannot be traced by interview or koseki has been studied by isonymy. The early work of Kainizaki, who indepen­dently discovered many of the principles of isonymy, is reviewed

The Distribution of Distance between Birthplaces of Mates

The distribution of matrimonial distance is studied with special reference to population genetics theory. The model built is based on random diffusion of every person, who then stops his movement at the age of marriage. The time of stopping, or the age at marriage in the present model, fits satisfactorily a gamma distribution. The expected probability of matrimonial distance, based on random diffusion with a gamma stopping time of movement, is examined for three local populations from small cities of Japan. It is found that the fit is consistently with the K-distribution. For fixed age, the distribution of matrimonial distance is normal, except for very short distances. In the present materials, the correlation coefficient between the distance and the age of marriage is not significantly different from zero. Thus, the variation of individual mobility, measured by the diffusion coefficient, overrides the variance of age at marriage. If the age effect on the distribution of matrimonial distance is first order, this correlation would be expected to be strong. It is also found that immigration is very active in Ohdate and Mine as well, so that it would be very difficult to maintain a characteristically genetic specificity in these small groups from the other parts of Japan. The estimated standard deviations of migration in local groups are respectively 5.59 km, 1.54 km and 6.54 km in Ohdate, Misima and Mine

The genetical structure of northeastern Brazil

Typescript.Thesis (Ph. D.)--University of Hawaii, 1966.Bibliography: leaves 139-146.x, 232 l mounted illus., tables (part mounted