The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D. erecta, D. mojavensis, and D. grimshawi F elements and euchromatic domains from the Muller D element. We find that F elements have greater transposon density (25–50%) than euchromatic reference regions (3–11%). Among the F elements, D. grimshawi has the lowest transposon density (particularly DINE-1: 2% vs. 11–27%). F element genes have larger coding spans, more coding exons, larger introns, and lower codon bias. Comparison of the Effective Number of Codons with the Codon Adaptation Index shows that, in contrast to the other species, codon bias in D. grimshawi F element genes can be attributed primarily to selection instead of mutational biases, suggesting that density and types of transposons affect the degree of local heterochromatin formation. F element genes have lower estimated DNA melting temperatures than D element genes, potentially facilitating transcription through heterochromatin. Most F element genes (~90%) have remained on that element, but the F element has smaller syntenic blocks than genome averages (3.4–3.6 vs. 8.4–8.8 genes per block), indicating greater rates of inversion despite lower rates of recombination. Overall, the F element has maintained characteristics that are distinct from other autosomes in the Drosophila lineage, illuminating the constraints imposed by a heterochromatic milieu.
IntroductionCalifornia’s law raising the minimum tobacco sales age to 21 went into effect on 9 June 2016. This law, known as ‘Tobacco 21’ or ‘T21’, also expanded the definition of tobacco to include electronic smoking devices. This paper describes the T21 evaluation plan and initial evaluation results.MethodsAn evaluation plan and logic model were created to evaluate T21. A tobacco retailer poll was conducted 7 months after the law went into effect to assess awareness, support and implementation; an online survey of California adults was fielded to provide data on tobacco use and attitudinal changes before and after T21 implementation; and tobacco purchase surveys were conducted to assess the retailer violation rate (RVR). Multivariate models estimated the odds of RVR and odds of being aware, agreeing with and observing advertisements related to T21.ResultsSeven months after the T21 effective date, 98.6% of retailers were aware of the law and 60.6% supported the law. Furthermore, 66.2% of retailers agreed that people who start smoking before 21 would become addicted to tobacco products. The RVR using youth decoys under age 18 statistically decreased from 10.3% before T21 to 5.7% after T21 (P=0.002). Furthermore, the RVR using young adult decoys ages 18–19 was 14.2% (95% CI 9.3% to 19.1%) for traditional tobacco and 13.1% (95% CI 10.2% to 16.1%) for electronic smoking devices.ConclusionsSurvey findings suggest that the high awareness and support for the law may have contributed to reducing illegal tobacco sales to youth under 18 and achieving widespread retailer conformity with the new law disallowing sales to young adults under 21.
The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains.
OBJECTIVE The study examined the relationship between functional limitation due to chronic diseases and absenteeism among full-time workers. The studied chronic diseases include: arthritis/rheumatism, cancer, diabetes, heart disease, hypertension, lung disease, and stroke. METHODS We analyzed data from the 2011–2013 National Health Interview Survey. Economic impact was determined by workdays lost and lost income. RESULTS Increase in absenteeism was observed for each studied condition. Employees with multiple conditions also saw increase absenteeism. Employers lose 28.2 million workdays annually ($4.95 billion in lost income) due to functional limitation caused by chronic diseases. CONCLUSION The results show a burden on society due to functional limitation caused by studied chronic diseases. Employers should look into implementing intervention/prevention programs, such as the Chronic Disease Self-Management Programs, to help reduce the cost associated with absenteeism.
estimates, the least expensive of the 3 methods. A possible explanation for this finding is that parent estimates yielded relatively high sensitivity and specificity, leaving limited room for improvement. A European study of preschool children reported lower sensitivity (47%) and similar specificity (93%) of parent estimates relative to our findings and reached the same conclusion: parent measurements did not improve overweight/obese status classification over parent estimates. 4 Our study has some limitations. The children included in this sample were predominantly non-Hispanic black and Hispanic and were from low-income households, limiting the generalizability of our findings to other populations. In addition, the subsample from the New Jersey Child Health Study that we used depended on parents' willingness to participate in additional measurements. However, the demographic characteristics of the subsample were similar to those of the overall New Jersey Child Health Study. Our study indicates that parent estimates and parent measurements of children's height and weight are both effective in classifying weight status. Therefore, when professionally measured data cannot be collected, parent estimates represent the most efficient alternative, as they are less resource intensive than parent measurements but without any trade-off in accuracy.
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