328 research outputs found

    Prevalence and determinants of cigarette smoking relapse among US adult smokers: a longitudinal study

    Get PDF
    Objectives This research project aims at estimating the prevalence of cigarette smoking relapse and determining its predictors among adult former smokers in the USA. Setting This research analysed secondary data retrieved from the Tobacco Use Supplement-Current Population Survey 2010–2011 cohort in the USA. Participants Out of 18 499 participants who responded to the survey in 2010 and 2011, the analysis included a total sample size of 3258 ever smokers, who were living in the USA and reported quitting smoking in 2010. The survey’s respondents who never smoked or reported current smoking in 2010 were excluded from the study sample. Primary and secondary outcome measures Smoking relapse was defined as picking up smoking in 2011 after reporting smoking abstinence in 2010. The prevalence of relapse over the 12-month follow-up period was estimated among different subgroups. Multivariable logistic regression models were applied to determine factors associated with relapse. Results A total of 184 former smokers reported smoking relapse by 2011 (weighted prevalence 6.8%; 95% CI 5.7% to 8.1%). Prevalence and odds of relapse were higher among young people compared with elders. Former smokers living in smoke-free homes (SFHs) had 60% lower odds of relapse compared with those living in homes that allowed smoking inside (adjusted OR 0.40; 95% CI 0.25 to 0.64). Regarding race/ethnicity, only Hispanics showed significantly higher odds of relapse compared with Whites (non-Hispanics). Odds of relapse were higher among never married, widowed, divorced and separated individuals, compared with the married group. Continuous smoking cessation for 6 months or more significantly decreased odds of relapse. Conclusions Wider health determinants, such as race and age, but also living in SFHs showed significant associations with smoking relapse, which could inform the development of more targeted programmes to support those smokers who successfully quit, although further longitudinal studies are required to confirm our findings

    On the nonexistence of Liouvillian first integrals for generalized Liénard polynomial differential systems

    Get PDF
    International audienceWe consider generalized Liénard polynomial differential systems. In their work, Llibre and Valls have shown that, except in some particular cases, such systems have no Liouvillian first integral. In this letter, we give a direct and shorter proof of this result

    Molecular Dynamics Simulation Study of Nonconcatenated Ring Polymers in a Melt: I. Statics

    Full text link
    Molecular dynamics simulations were conducted to investigate the structural properties of melts of nonconcatenated ring polymers and compared to melts of linear polymers. The longest rings were composed of N=1600 monomers per chain which corresponds to roughly 57 entanglement lengths for comparable linear polymers. For the rings, the radius of gyration squared was found to scale as N to the 4/5 power for an intermediate regime and N to the 2/3 power for the larger rings indicating an overall conformation of a crumpled globule. However, almost all beads of the rings are "surface beads" interacting with beads of other rings, a result also in agreement with a primitive path analysis performed in the following paper (DOI: 10.1063/1.3587138). Details of the internal conformational properties of the ring and linear polymers as well as their packing are analyzed and compared to current theoretical models.Comment: 15 pages, 14 figure

    On the number of limit cycles of the Lienard equation

    Full text link
    In this paper, we study a Lienard system of the form dot{x}=y-F(x), dot{y}=-x, where F(x) is an odd polynomial. We introduce a method that gives a sequence of algebraic approximations to the equation of each limit cycle of the system. This sequence seems to converge to the exact equation of each limit cycle. We obtain also a sequence of polynomials R_n(x) whose roots of odd multiplicity are related to the number and location of the limit cycles of the system.Comment: 10 pages, 5 figures. Submitted to Physical Review

    Long-lived neutral-kaon flux measurement for the KOTO experiment

    Get PDF
    The KOTO (K0K^0 at Tokai) experiment aims to observe the CP-violating rare decay KLπ0ννˉK_L \rightarrow \pi^0 \nu \bar{\nu} by using a long-lived neutral-kaon beam produced by the 30 GeV proton beam at the Japan Proton Accelerator Research Complex. The KLK_L flux is an essential parameter for the measurement of the branching fraction. Three KLK_L neutral decay modes, KL3π0K_L \rightarrow 3\pi^0, KL2π0K_L \rightarrow 2\pi^0, and KL2γK_L \rightarrow 2\gamma were used to measure the KLK_L flux in the beam line in the 2013 KOTO engineering run. A Monte Carlo simulation was used to estimate the detector acceptance for these decays. Agreement was found between the simulation model and the experimental data, and the remaining systematic uncertainty was estimated at the 1.4\% level. The KLK_L flux was measured as (4.183±0.017stat.±0.059sys.)×107(4.183 \pm 0.017_{\mathrm{stat.}} \pm 0.059_{\mathrm{sys.}}) \times 10^7 KLK_L per 2×10142\times 10^{14} protons on a 66-mm-long Au target.Comment: 27 pages, 16 figures. To be appeared in Progress of Theoretical and Experimental Physic

    Characterization of cDNA clones of the family of trypsin/α-amylase inhibitors (CM-proteins) in barley (Hordeum vulgare L.)

    Get PDF
    Recombinants encoding members of the trypsin/-amylase inhibitors family (also designated CM-proteins) were selected from a cDNA library prepared from developing barley endosperm. Inserts in two of the clones, pUP-13 and pUP-38, were sequenced and found to encode proteins which clearly belong to this family, as judged from the extensive homology of the deduced sequences with that of the barley trypsin inhibitor CMe, the only member of the group for which a complete amino acid sequence has been obtained by direct protein sequencing. These results, together with previously obtained N-terminal sequences of purified CM-proteins, imply that there are at least six different members of this dispersed gene family in barley. The relationship of this protein family to the B-3 hordein and to reserve prolamins from related species is discussed in terms of their genome structure and evolution

    Cloning of cDNA and chromosomal location of genes encoding the three types of subunits of the wheat tetrameric inhibitor of insect a-amylase

    Get PDF
    We have characterized three cDNA clones corresponding to proteins CM1, CM3 and CM16, which represent the three types of subunits of the wheat tetrameric inhibitor of insect -amylases. The deduced amino acid sequences of the mature polypeptides are homologous to those of the dimeric and monomeric -amylase inhibitors and of the trypsin inhibitors. The mature polypeptides are preceded by typical signal peptides. Southern blot analysis of appropriate aneuploids, using the cloned cDNAs as probes, has revealed the location of genes for subunits of the CM3 and of the CM16 type within a few kb of each other in chromosomes 4A, 4B and 4D, and those for the CM1 type of subunit in chromosomes 7A, 7B and 7D. Known subunits of the tetrameric inhibitor corresponding to genes from the B and D genomes have been previously characterized. No proteins of this class have been found to be encoded by the A genome in hexaploid wheat (genomes AA, BB, DD) or in diploid wheats (AA) and no anti -amylase activity has been detected in the latter, so that the A-genome genes must be either silent (pseudogenes) or expressed at a much lower level

    The gene for trypsin inhibitor CMe is regulated in trans by the lys 3a locus in the endosperm of barley (Hordeum vulgare L.)

    Full text link
    A cDNA encoding trypsin inhibitor CMe from barley endosperm has been cloned and characterized. The longest open reading frame of the cloned cDNA codes for a typical signal peptide of 24 residues followed by a sequence which is identical to the known amino acid sequence of the inhibitor, except for an Ile/Leu substitution at position 59. Southern blot analysis of wheat-barley addition lines has shown that chromosome 3H of barley carries the gene for CMe. This protein is present at less than 2%–3% of the wild-type amount in the mature endosperm of the mutant Risø 1508 with respect to Bomi barley, from which it has been derived, and the corresponding steady state levels of the CMe mRNA are about I%. One or two copies of the CMe gene (synonym Itc1) per haploid genome have been estimated both in the wild type and in the mutant, and DNA restriction patterns are identical in both stocks, so neither a change in copy number nor a major rearrangement of the structural gene account for the markedly decreased expression. The mutation at the lys 3a locus in Risø 1508 has been previously mapped in chromosome 7 (synonym 5H). A single dose of the wild-type allele at this locus (Lys 3a) restores the expression of gene CMe (allele CMe-1) in chromosome 3H to normal levels

    Recent and historical recombination in the admixed Norwegian Red cattle breed

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Comparison of recent patterns of recombination derived from linkage maps to historical patterns of recombination from linkage disequilibrium (LD) could help identify genomic regions affected by strong artificial selection, appearing as reduced recent recombination. Norwegian Red cattle (NRF) make an interesting case study for investigating these patterns as it is an admixed breed with an extensively recorded pedigree. NRF have been under strong artificial selection for traits such as milk and meat production, fertility and health.</p> <p>While measures of LD is also crucial for determining the number of markers required for association mapping studies, estimates of recombination rate can be used to assess quality of genomic assemblies.</p> <p>Results</p> <p>A dataset containing more than 17,000 genome-wide distributed SNPs and 2600 animals was used to assess recombination rates and LD in NRF. Although low LD measured by r<sup>2 </sup>was observed in NRF relative to some of the breeds from which this breed originates, reports from breeds other than those assessed in this study have described more rapid decline in r<sup>2 </sup>at short distances than what was found in NRF. Rate of decline in r<sup>2 </sup>for NRF suggested that to obtain an expected r<sup>2 </sup>between markers and a causal polymorphism of at least 0.5 for genome-wide association studies, approximately one SNP every 15 kb or a total of 200,000 SNPs would be required. For well known quantitative trait loci (QTLs) for milk production traits on <it>Bos Taurus </it>chromosomes 1, 6 and 20, map length based on historic recombination was greater than map length based on recent recombination in NRF.</p> <p>Further, positions for 130 previously unpositioned contigs from assembly of the bovine genome sequence (Btau_4.0) found using comparative sequence analysis were validated by linkage analysis, and 28% of these positions corresponded to extreme values of population recombination rate.</p> <p>Conclusion</p> <p>While LD is reduced in NRF compared to some of the breeds from which this admixed breed originated, it is elevated over short distances compared to some other cattle breeds. Genomic regions in NRF where map length based on historic recombination was greater than map length based on recent recombination coincided with some well known QTL regions for milk production traits.</p> <p>Linkage analysis in combination with comparative sequence analysis and detection of regions with extreme values of population recombination rate proved to be valuable for detecting problematic regions in the Btau_4.0 genome assembly.</p
    corecore