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81.
Background
Having children creates career interruptions and reductions in labor income for women. This study documents the relation between the age at first birth (AFB) and women’s labor income. We study these dynamics in the short run (i.e. ratio between labor income at AFB and two years prior to AFB) and long run (i.e., positive/negative differences in total lifetime labor income).Methods
Using unique Danish administrative register data for the entire Danish population, we estimate the age-income profiles separately for college and non-college women conditional on marital status, and mothers’ age at first birth (AFB). We compute the lifetime labor income differentials by taking the differences between the labor income of women with and without children at each AFB.Results
The short-run loss in labor income, defined as the difference in percentages between the income earned two years prior to AFB and income earned at AFB, ranges from 37% to 65% for college women and from 40% to 53% for non-college women. These losses decrease monotonically with respect to AFB for both education groups. Our results on the lifetime labor income differentials between mothers and women without children also show a net effect that is monotonic (from negative to positive) in AFB. With AFB<25, the lifetime labor income loss for college women is -204% of their average annual labor income and this figure is -252% for non-college women. There are lifetime labor income gains with AFB>31. The largest gains for college women are 13% of their average annual income and this figure is 50% for non-college women.Conclusion
Women have a large and unambiguous short-run reduction in labor income at their AFB. In terms of lifetime labor income, both college and non-college women, compared to childless women, are associated with lower income of more than twice their respective average annual income when bearing a child at AFB<25. In other words, women with AFB<25 are associated with a lower lifetime income of more than two years of annual labor income. The lifetime labor incomes for college and non-college women associated with AFB>31 are relatively higher. 相似文献82.
Julia A. Sabet Lara K. Park Lakshmanan K. Iyer Albert K. Tai Gar Yee Koh Anna C. Pfalzer Laurence D. Parnell Joel B. Mason Zhenhua Liu Alexander J. Byun Jimmy W. Crott 《PloS one》2016,11(3)
Background
The importance of maternal nutrition to offspring health and risk of disease is well established. Emerging evidence suggests paternal diet may affect offspring health as well.Objective
In the current study we sought to determine whether modulating pre-conception paternal B vitamin intake alters intestinal tumor formation in offspring. Additionally, we sought to identify potential mechanisms for the observed weight differential among offspring by profiling hepatic gene expression and lipid content.Methods
Male Apc1638N mice (prone to intestinal tumor formation) were fed diets containing replete (control, CTRL), mildly deficient (DEF), or supplemental (SUPP) quantities of vitamins B2, B6, B12, and folate for 8 weeks before mating with control-fed wild type females. Wild type offspring were euthanized at weaning and hepatic gene expression profiled. Apc1638N offspring were fed a replete diet and euthanized at 28 weeks of age to assess tumor burden.Results
No differences in intestinal tumor incidence or burden were found between male Apc1638N offspring of different paternal diet groups. Although in female Apc1638N offspring there were no differences in tumor incidence or multiplicity, a stepwise increase in tumor volume with increasing paternal B vitamin intake was observed. Interestingly, female offspring of SUPP and DEF fathers had a significantly lower body weight than those of CTRL fed fathers. Moreover, hepatic trigylcerides and cholesterol were elevated 3-fold in adult female offspring of SUPP fathers. Weanling offspring of the same fathers displayed altered expression of several key lipid-metabolism genes. Hundreds of differentially methylated regions were identified in the paternal sperm in response to DEF and SUPP diets. Aside from a few genes including Igf2, there was a striking lack of overlap between these genes differentially methylated in sperm and differentially expressed in offspring.Conclusions
In this animal model, modulation of paternal B vitamin intake prior to mating alters offspring weight gain, lipid metabolism and tumor growth in a sex-specific fashion. These results highlight the need to better define how paternal nutrition affects the health of offspring. 相似文献83.
Agnes Y. Lai Moses W. Mui Alice Wan Sunita M. Stewart Carol Yew Tai-hing Lam Sophia S. Chan 《PloS one》2016,11(1)
Evidence-based practice and capacity-building approaches are essential for large-scale health promotion interventions. However, there are few models in the literature to guide and evaluate training of social service workers in community settings. This paper presents the development and evaluation of the “train-the-trainer” workshop (TTT) for the first large scale, community-based, family intervention projects, entitled “Happy Family Kitchen Project” (HFK) under the FAMILY project, a Hong Kong Jockey Club Initiative for a Harmonious Society. The workshop aimed to enhance social workers’ competence and performance in applying positive psychology constructs in their family interventions under HFK to improve family well-being of the community they served. The two-day TTT was developed and implemented by a multidisciplinary team in partnership with community agencies to 50 social workers (64% women). It focused on the enhancement of knowledge, attitude, and practice of five specific positive psychology themes, which were the basis for the subsequent development of the 23 family interventions for 1419 participants. Acceptability and applicability were enhanced by completing a needs assessment prior to the training. The TTT was evaluated by trainees’ reactions to the training content and design, changes in learners (trainees) and benefits to the service organizations. Focus group interviews to evaluate the workshop at three months after the training, and questionnaire survey at pre-training, immediately after, six months, one year and two years after training were conducted. There were statistically significant increases with large to moderate effect size in perceived knowledge, self-efficacy and practice after training, which sustained to 2-year follow-up. Furthermore, there were statistically significant improvements in family communication and well-being of the participants in the HFK interventions they implemented after training. This paper offers a practical example of development, implementation and model-based evaluation of training programs, which may be helpful to others seeking to develop such programs in diverse communities. 相似文献
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87.
Transformation of galena to pyromorphite produces bioavailable sulfur for neutrophilic chemoautotrophy
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The aqueous concentration of lead [Pb(II)] in geochemical environments is controlled by the solubility of Pb‐bearing minerals and their weathering products. In contaminated soils, a common method for in situ stabilization of Pb(II) is the addition of phosphate to convert more redox sensitive sulfide minerals into sparingly soluble pyromorphite [Pb5(PO4)3X]. In this study, we conducted experimental studies to investigate the fate of reduced sulfur during the conversion of galena [PbS] to chloropyromorphite [Pb5(PO4)3Cl]. Powder X‐ray diffraction analysis indicated that the reaction of phosphate with galena under oxic conditions resulted in the oxidation of sulfide and formation of elemental sulfur [S8]. Under oxic abiotic conditions, the S8 was retained in the solid phase, and negligible concentrations of sulfur as sulfide and thiosulfate were detected in the aqueous phase and only a small amount of sulfate. When PbS reacted in the presence of the chemoautotrophic organism Bosea sp. WAO, the S8 in the secondary mineral was oxidized to sulfate. Strain WAO produced significantly more sulfate from the secondary S8 than from the primary galena. Microscopic analysis of mineral–microbe aggregates on mineral‐embedded slide cultures showed that the organism was colocalized and increased in biomass over time on the secondary mineral surface supporting a microbial role. The results of this study indicate that stimulation of sulfur‐oxidizing activity may be a direct consequence of phosphate amendments to Pb(II)‐contaminated soils. 相似文献
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