The purpose of the present study was to revise the Barratt Impulsiveness Scale Version 10 (BIS‐10), identify the factor structure of the items among normals, and compare their scores on the revised form (BIS‐11) with psychiatric inpatients and prison inmates. The scale was administered to 412 college undergraduates, 248 psychiatric inpatients, and 73 male prison inmates. Exploratory principal components analysis of the items identified six primary factors and three second‐order factors. The three second‐order factors were labeled Attentional Impulsiveness, Motor Impulsiveness, and Nonplanning Impulsiveness. Two of the three second‐order factors identified in the BIS‐11 were consistent with those proposed by Barratt (1985), but no cognitive impulsiveness component was identified per se. The results of the present study suggest that the total score of the BIS‐11 is an internally consistent measure of impulsiveness and has potential clinical utility for measuring impulsiveness among selected patient and inmate populations.

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SummaryThe bowhead whale (Balaena mysticetus) is estimated to live over 200 years and is possibly the longest-living mammal. These animals should possess protective molecular adaptations relevant to age-related diseases, particularly cancer. Here, we report the sequencing and comparative analysis of the bowhead whale genome and two transcriptomes from different populations. Our analysis identifies genes under positive selection and bowhead-specific mutations in genes linked to cancer and aging. In addition, we identify gene gain and loss involving genes associated with DNA repair, cell-cycle regulation, cancer, and aging. Our results expand our understanding of the evolution of mammalian longevity and suggest possible players involved in adaptive genetic changes conferring cancer resistance. We also found potentially relevant changes in genes related to additional processes, including thermoregulation, sensory perception, dietary adaptations, and immune response. Our data are made available online (http://www.bowhead-whale.org) to facilitate research in this long-lived species.

The components underlying items from a comprehensive but diverse domain of impulsivity measures were investigated. The disparity of items within this domain attests to the lack of a coherent framework from which to conceptualize impulsivity. The self-report measures included in this study were the 16PF Impulsivity scale, the GZTS Restraint, Thoughtfulness and General Activity scales, the PRF Impulsivity scale, the EASI-III Impulsivity scale, the BIS-8 and BIS-10, the I-5 and I-7, the SSS, and selected MMPI items. Behavioral measures included in this study were the MFFT, Simple Reaction Time, Time Estimation, and Time Production. From a restricted factor analysis (without correlated measurement errors) of the responses of 379 subjects to the 373 self-report items and of 228 subjects (or more) to each of the behavioral measures, 15 distinct impulsivity components were identified, with moderate to low and some negative correlations. From the analysis of the corresponding scales, a second-order model revealed three broad impulsivity factors: Spontaneous, Not Persistent, and Carefree. Implications of these results were discussed for establishing a coherent conceptualization and measurement strategy of impulsivity based, for example, on this derived second-order structure.

Restriction endonuclease assay of mitochondria DNA (mtDNA) and standard starch-gel electrophoresis of proteins encoded by nuclear genes have been used to analyze phylogenetic relatedness among a large number of pocket gophers (Geomys pinetis) collected throughout the range of the species. The restriction analysis clearly distinguishes two populations within the species, an eastern and a western form, which differ by at least 3% in mtDNA sequence. Qualitative comparisons of the restriction phenotypes can also be used to identify mtDNA "clones" within each form. The mtDNA clones interconnect in a phylogenetic network which represents an estimate of matriarchal phylogeny for G. pinetis. Although the protein electrophoretic data also differentiate the eastern and western forms, the data are of limited usefulness in establishing relationships among more local subpopulations. The comparison between these two data sets suggests that restriction analysis of mtDNA is probably unequalled by other techniques currently available for determining phylogenetic relationships among conspecific organisms. Type II restriction endonucleases cleave duplex DNA at specific recognition sites usually containing four, five, or six nucleotides (1, 2). The fragment patterns produced by the digestion of two homologous DNA molecules can differ because they are differentially modified (i.e., by methylation of bases within the recognition sites), nucleotide substitutions have abolished cleavage sites or created new ones, or major sequence rearrangements have altered the relative positions of cleavage sites within the molecules. Restriction endonucleases have been used to compare mtDNA sequences from a variety of mammalian sources. These studies have shown that the population of mtDNA molecules within an individual animal appears homogeneous in sequence (3, 4), mtDNA does not appear to be modified in ways that affect digestion (3, 5), mtDNA is maternally inherited (3,(6)(7)(8), and mtDNA evolves rapidly enough to produce easily detectable sequence heterogeneity within species (3,4,6,9,10). These observations provide the rationale for the use of restriction analysis of mtDNA to identify mtDNA "clones" in nature and to estimate their evolutionary geneology (phylogeny).Critical assessment of the utility of any new information used for phylogenetic reconstruction is hampered by the fact that the true evolutionary history of the populations or species being studied is seldom if ever known. In the absence of an absolute calibration, the potential of a new approach can be evaluated only by comparing results with those obtained by independent methods. Gel electrophoresis of proteins is the simplest and strongest technique in current use for estimating the genetic relatedness of closely similar organisms. We have, therefore, performed both protein electrophoretic and mtDNA restriction analyses with a large number of individuals of the pocket gopher, Geomys pinetis, live-trapped throughout the range of the species

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We analyzed intraspecific mitochondrial DNA variation in chinook salmon (Oncorhynchus tshawytscha) from drainages in the Yukon River (Alaska and Yukon Territory), the Kenai River (Alaska), and Oregon and California rivers; and chum salmon (O. keta) from the Yukon River and Vancouver Island, and Washington rivers. For each species, three different portions of the mtDNA molecule were amplified separately using the polymerase chain reaction and then digested with at least 19 restriction enzymes. Intraspecific sequence divergences between haplotypes were less than 0.01 base substitution per nucleotide. Nine chum salmon haplotypes were identified. Yukon River chum salmon stocks displayed more haplotypes (eight) than the stocks of Vancouver Island and Washington (two). The most common chum salmon haplotype occurred in all areas. Seven chinook salmon haplotypes were identified. Four haplotypes occurred in the Yukon and Kenai rivers and four occurred in Oregon/California, with only one haplotype shared between the regions. Sample sizes were too small to quantify the degree of stock separation among drainages, but the patterns of variation that we observed suggest utility of the technique in genetic stock identification.

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