A Prospective Sociocentric Study of 2 Entire Traditional Korean Villages: The Korean Social Life, Health, and Aging Project (KSHAP).

The Korean Social Life, Health, and Aging Project (KSHAP) was a multidisciplinary prospective study conducted in South Korea that measured various health biomarkers from blood, hair, and brain magnetic resonance imaging, and we examined their associations with sociocentric (global) social network data of older adults in 2 entire villages (or cohorts). Cohort K included participants aged 60 years or older, and cohort L included participants aged 65 years or older. We performed a baseline survey involving 814 of the 860 individuals (94.7% response rate) in cohort K in 2012 and 947 of the 1,043 individuals (90.8% response rate) in cohort L in 2017. We gathered longitudinal data for 5 waves in cohort K from 2011 to 2019 and 2 waves in cohort L from 2017 to 2022. Here, we describe for the first time the follow-up design of the KSHAP, the changes in social networks, and various biomarkers over a number of years. The data for cohort K are publicly available via the Korean Social Science Data Archive as well as the project website, and the data for cohort L will be shared soon.

Metheor: Ultrafast DNA methylation heterogeneity calculation from bisulfite read alignments.

Phased DNA methylation states within bisulfite sequencing reads are valuable source of information that can be used to estimate epigenetic diversity across cells as well as epigenomic instability in individual cells. Various measures capturing the heterogeneity of DNA methylation states have been proposed for a decade. However, in routine analyses on DNA methylation, this heterogeneity is often ignored by computing average methylation levels at CpG sites, even though such information exists in bisulfite sequencing data in the form of phased methylation states, or methylation patterns. In this study, to facilitate the application of the DNA methylation heterogeneity measures in downstream epigenomic analyses, we present a Rust-based, extremely fast and lightweight bioinformatics toolkit called Metheor. As the analysis of DNA methylation heterogeneity requires the examination of pairs or groups of CpGs throughout the genome, existing softwares suffer from high computational burden, which almost make a large-scale DNA methylation heterogeneity studies intractable for researchers with limited resources. In this study, we benchmark the performance of Metheor against existing code implementations for DNA methylation heterogeneity measures in three different scenarios of simulated bisulfite sequencing datasets. Metheor was shown to dramatically reduce the execution time up to 300-fold and memory footprint up to 60-fold, while producing identical results with the original implementation, thereby facilitating a large-scale study of DNA methylation heterogeneity profiles. To demonstrate the utility of the low computational burden of Metheor, we show that the methylation heterogeneity profiles of 928 cancer cell lines can be computed with standard computing resources. With those profiles, we reveal the association between DNA methylation heterogeneity and various omics features. Source code for Metheor is at https://github.com/dohlee/metheor and is freely available under the GPL-3.0 license.

Towards multi-omics characterization of tumor heterogeneity: a comprehensive review of statistical and machine learning approaches.

The multi-omics molecular characterization of cancer opened a new horizon for our understanding of cancer biology and therapeutic strategies. However, a tumor biopsy comprises diverse types of cells limited not only to cancerous cells but also to tumor microenvironmental cells and adjacent normal cells. This heterogeneity is a major confounding factor that hampers a robust and reproducible bioinformatic analysis for biomarker identification using multi-omics profiles. Besides, the heterogeneity itself has been recognized over the years for its significant prognostic values in some cancer types, thus offering another promising avenue for therapeutic intervention. A number of computational approaches to unravel such heterogeneity from high-throughput molecular profiles of a tumor sample have been proposed, but most of them rely on the data from an individual omics layer. Since the heterogeneity of cells is widely distributed across multi-omics layers, methods based on an individual layer can only partially characterize the heterogeneous admixture of cells. To help facilitate further development of the methodologies that synchronously account for several multi-omics profiles, we wrote a comprehensive review of diverse approaches to characterize tumor heterogeneity based on three different omics layers: genome, epigenome and transcriptome. As a result, this review can be useful for the analysis of multi-omics profiles produced by many large-scale consortia. Contact:sunkim.bioinfo@snu.ac.kr.

BioVLAB-Cancer-Pharmacogenomics: tumor heterogeneity and pharmacogenomics analysis of multi-omics data from tumor on the cloud.

MOTIVATION: Multi-omics data in molecular biology has accumulated rapidly over the years. Such data contains valuable information for research in medicine and drug discovery. Unfortunately, data-driven research in medicine and drug discovery is challenging for a majority of small research labs due to the large volume of data and the complexity of analysis pipeline. RESULTS: We present BioVLAB-Cancer-Pharmacogenomics, a bioinformatics system that facilitates analysis of multi-omics data from breast cancer to analyze and investigate intratumor heterogeneity and pharmacogenomics on Amazon Web Services. Our system takes multi-omics data as input to perform tumor heterogeneity analysis in terms of TCGA data and deconvolve-and-match the tumor gene expression to cell line data in CCLE using DNA methylation profiles. We believe that our system can help small research labs perform analysis of tumor multi-omics without worrying about computational infrastructure and maintenance of databases and tools. AVAILABILITY AND IMPLEMENTATION: http://biohealth.snu.ac.kr/software/biovlab_cancer_pharmacogenomics. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Optimum Urine Cotinine and NNAL Levels to Distinguish Smokers from Non-Smokers by the Changes in Tobacco Control Policy in Korea from 2008 to 2018.

INTRODUCTION: We examined the age- and sex-specific distributions of biomarkers of tobacco smoke exposure to determine the optimal cutoffs to distinguish smokers from non-smokers over the last 10 years in Korea, during which smoking prevalence and secondhand smoke (SHS) exposure declined due to changes in tobacco control policy. METHODS: We analyzed data from the Korea National Health and Nutrition Examination Survey on creatinine-adjusted urinary cotinine (2008-2018; 33 429 adults: 15 653 males and 17 776 females) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; 2016-2018; 6337 adults: 3091 males and 3246 females). We determined the optimal cutoffs and confidence intervals (CIs) to distinguish smokers from non-smokers using receiver operator characteristic curve analysis and bootstrapping (1000 resamples). RESULTS: The optimal cutoff values of creatinine-adjusted urine cotinine and NNAL concentration were 20.9 ng/mg (95% CI: 20.8-21.0, sensitivity: 96.6%, specificity: 93.8%) and 8.9 pg/mg (95% CI: 8.8-8.9, sensitivity: 94.0%, specificity: 94.7%), respectively, in 2016-2018. The optimal cutoffs of both biomarkers increased with age and were higher in females than in males for NNAL concentration. In both sexes, the optimal cutoff of urine cotinine continuously declined over the study period. CONCLUSIONS: The optimal cotinine cutoff declined along with smoking prevalence and levels of SHS exposure due to enforcement of tobacco control policies, including smoke-free ordinances and tax increases. Monitoring of biomarkers of tobacco exposure appears necessary for verification of smoking status and regulatory use. IMPLICATIONS: Our results based on nationally representative data suggest that a large decrease in the optimal cutoff value of urine cotinine to distinguish smokers from non-smokers was caused by decreases in smoking prevalence and SHS exposure following enforcement of tobacco control policies over the last 10 years. We determined the optimal cutoff values of urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which were not previously reported in representative population in Asia, to enable more accurate estimation of exposure to tobacco smoke and proper assessment of disease risks. Gender- and age-specific differences in the optimal cutoffs require further study. Monitoring of biomarkers of tobacco smoke exposure seems necessary for verification of smoking status and regulatory use.

PRISM: methylation pattern-based, reference-free inference of subclonal makeup.

MOTIVATION: Characterizing cancer subclones is crucial for the ultimate conquest of cancer. Thus, a number of bioinformatic tools have been developed to infer heterogeneous tumor populations based on genomic signatures such as mutations and copy number variations. Despite accumulating evidence for the significance of global DNA methylation reprogramming in certain cancer types including myeloid malignancies, none of the bioinformatic tools are designed to exploit subclonally reprogrammed methylation patterns to reveal constituent populations of a tumor. In accordance with the notion of global methylation reprogramming, our preliminary observations on acute myeloid leukemia (AML) samples implied the existence of subclonally occurring focal methylation aberrance throughout the genome. RESULTS: We present PRISM, a tool for inferring the composition of epigenetically distinct subclones of a tumor solely from methylation patterns obtained by reduced representation bisulfite sequencing. PRISM adopts DNA methyltransferase 1-like hidden Markov model-based in silico proofreading for the correction of erroneous methylation patterns. With error-corrected methylation patterns, PRISM focuses on a short individual genomic region harboring dichotomous patterns that can be split into fully methylated and unmethylated patterns. Frequencies of such two patterns form a sufficient statistic for subclonal abundance. A set of statistics collected from each genomic region is modeled with a beta-binomial mixture. Fitting the mixture with expectation-maximization algorithm finally provides inferred composition of subclones. Applying PRISM for two AML samples, we demonstrate that PRISM could infer the evolutionary history of malignant samples from an epigenetic point of view. AVAILABILITY AND IMPLEMENTATION: PRISM is freely available on GitHub (https://github.com/dohlee/prism). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Chryseobacterium vaccae sp. nov., isolated from raw cow's milk.

Strain CA7T, a Gram-stain-negative, non-motile, non-spore-forming, aerobic and rod-shaped bacterial strain, was isolated from raw cow's milk collected from a farm affiliated with Chung-Ang University, Anseong, Korea, and characterized by a polyphasic approach. Optimal growth of strain CA7T was observed on tryptic soy agar at 30 °C and pH 7.0 with 0 % NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain CA7T belonged to the genus Chryseobacterium. The most closely related strains (16S rRNA gene sequence similarity indicated in parentheses), based on the phylogenetic analysis, were Chryseobacterium rhizosphaerae KCTC 22548T (98.08 %), Chryseobacterium nakagawai CCUG 60563T (98.61 %), Chryseobacterium jejuense KACC 12501T (97.85 %) and Chryseobacterium aurantiacum KCTC 62135T (97.78 %). Whole genome sequencing indicated that the genome size was 5 125 723 bp and had a DNA G+C content of 37.4 mol%. Average nucleotide identity values for strain CA7T with C. rhizosphaerae, C. nakagawai, C. jejuense, C. aurantiacum, and the type species of the genus Chryseobacterium, C. gleum, were 80.2, 79.8, 79.8, 79.6 and 80.4 %, respectively. The digital DNA-DNA hybridization values of CA7T compared to C. rhizosphaerae, C. nakagawai, C. jejuense, C. aurantiacum and C. gleum were 24.1, 23.9, 23.9, 23.7 and 24.3 %, respectively. The major fatty acids were iso-C15 : 0, summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 0 10-methyl), iso-C17 : 0 3-OH and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1 ω7c). Menaquinone-6 was the only respiratory quinone. The major polar lipid was phosphatidylethanolamine. Based on this polyphasic taxonomic study, strain CA7T represents a novel species of the genus Chryseobacterium for which the name Chryseobacterium vaccae sp. nov. is proposed. The type strain is CA7T (=KACC 21402T=JCM 33749T).

Characterization of a non-phosphotransferase system for cis,cis-muconic acid production in Corynebacterium glutamicum.

Cis,cis-muconic acid (CCM) is a biochemical material that can be used for the production of various plastics and polymers and is particularly gaining attention as an adipic acid precursor for the synthesis of nylon-6,6. In the current study, the production of CCM was first attempted by introducing a newly developed protocatechuate (PCA) decarboxylase from Corynebacterium glutamicum 13032 to inha103, which completed the biosynthetic pathway therein. To improve CCM productivity, a phosphoenol pyruvate (PEP)-dependent phosphotransferase system (PTS) that consumed the existing glucose was developed, in the form of a strain with a non-PTS that did not consume PEP. To improve glucose uptake, we developed P25 strain, in which iolR (a transcriptional regulator gene) was additionally deleted. Strain P28, a P25 derivative expressing PCA decarboxylase, produced 4.01 g/L of CCM, which was 14% more than that produced by the parental strain. Moreover, strains P29 and P30, with an active pentose phosphate pathway and overexpressing important genes (qsuB) in the metabolic pathway, produced 4.36 and 4.5 g/L of CCM, respectively. Particularly, the yield per glucose in strain P30 was similar to that of the fed-batch culture of Escherichia coli, which has the highest reported yield of 22% (mol/mol). These results are underpinned by the characteristics of the non-PTS with increased PEP availability and a strain with deletion of the iolR gene, which greatly increased glucose uptake.

Risk of Interval Cancer in Fecal Immunochemical Test Screening Significantly Higher During the Summer Months: Results from the National Cancer Screening Program in Korea.

OBJECTIVES: This study aimed to evaluate the impact of seasonal variations in climate on the performance of the fecal immunochemical test (FIT) in screening for colorectal cancer in the National Cancer Screening Program in Korea. METHODS: Data were extracted from the National Cancer Screening Program databases for participants who underwent FIT between 2009 and 2010. We compared positivity rates, cancer detection rates, interval cancer rates, positive predictive value, sensitivity, and specificity for FIT during the spring, summer, fall, and winter seasons in Korea. RESULTS: In total, 4,788,104 FIT results were analyzed. FIT positivity rate was lowest during the summer months. In the summer, the positive predictive value of FIT was about 1.1 times (adjusted odds ratio (aOR) 1.08, 95% confidence interval (CI) 1.00-1.16) higher in the overall FIT group and about 1.3 times (aOR 1.29, 95% CI 1.10-1.50) higher in the quantitative FIT group, compared to those in the other seasons. Cancer detection rates, however, were similar regardless of season. Interval cancer risk was significantly higher in the summer for both the overall FIT group (aOR 1.16, 95% CI 1.07-1.27) and the quantitative FIT group (aOR 1.31, 95% CI 1.12-1.52). In addition, interval cancers in the rectum and distal colon were more frequently detected in the summer and autumn than in the winter. CONCLUSIONS: The positivity rate of FIT was lower in the summer, and the performance of the FIT screening program was influenced by seasonal variations in Korea. These results suggest that more efforts to reduce interval cancer during the summer are needed in population-based screening programs using FIT, particularly in countries with high ambient temperatures.

Higher satisfaction with an alternative collection device for stool sampling in colorectal cancer screening with fecal immunochemical test: a cross-sectional study.

BACKGROUND: Identifying preferences for stool collection devices may help increase uptake rates for colorectal cancer screening via fecal immunochemical test (FIT). This study surveyed satisfaction with different devices utilized to collect stool samples for FIT: a conventional container and a sampling bottle (Eiken OC-Sensor). METHODS: This cross-sectional study was conducted at the National Cancer Center, Korea. Participants aged 50-74 years who used either a conventional container or a sampling bottle to collect a stool sample for FIT were asked to complete a questionnaire designed to survey their satisfaction with the stool collection process and their intentions to undergo FIT in subsequent screening rounds. In total, 1657 participants (1224 conventional container, 433 sampling bottle) were included for analysis. RESULTS: Satisfaction with the sampling bottle was higher than that with the conventional container (79.9% vs.73.0%, p = 0.005, respectively; aOR = 1.52, 95% CI: 1.16-2.00). Participants satisfied with the sampling bottle were more likely to be female, be of younger age (50-64 years old), have higher household income, and have prior experience with FIT. Intentions to undergo subsequent screening were stronger among those given the sampling bottle than those given the conventional container (aOR = 1.78, 95% CI: 1.28-2 .48). CONCLUSIONS: Satisfaction with the stool collection process was higher with the sampling bottle. However, additional studies are needed to validate whether the increased satisfaction and stronger intentions to undergo subsequent screening with the sampling bottle could actually lead to increased uptake in subsequent rounds, along with analysis of the device's cost effectiveness.

Effect of supercritical carbon dioxide on the enzymatic production of biodiesel from waste animal fat using immobilized Candida antarctica lipase B variant.

BACKGROUND: Waste animal fat is a promising feedstock to replace vegetable oil that widely used in commercial biodiesel process, however the high content of free fatty acid in waste fat makes it unfeasible to be processed with commercial base-catalytic process. Enzymatic process is preferable to convert waste fat into biodiesel since enzyme can catalyze both esterification of free fatty acid and transesterification of triglyceride. However, enzymatic reaction still has some drawbacks such as lower reaction rates than base-catalyzed transesterification and the limitation of reactant concentration due to the enzyme inhibition of methanol. Supercritical CO2 is a promising reaction media for enzyme-catalyzed transesterification to overcome those drawbacks. RESULT: The transesterification of waste animal fat was carried out in supercritical CO2 with varied concentration of feedstock and methanol in CO2. The CO2 to feedstock mass ratio of 10:1 showed the highest yield compared to other ratios, and the highest FAME yield obtained from waste animal fat was 78%. The methanol concentration effect was also observed with variation 12%, 14%, and 16% of methanol to feedstock ratio. The best yield was 87% obtained at the CO2 to feedstock ratio of 10: 1 and at the methanol to feedstock ratio of 14% after 6 h of reaction. CONCLUSION: Enzymatic transesterification to produce biodiesel from waste animal fat in supercritical fluid media is a potential method for commercialization since it could enhance enzyme activity due to supercritical fluid properties to remove mass transfer limitation. The high yield of FAME when using high mass ratio of CO2 to oil showed that supercritical CO2 could increase the reaction and mass transfer rate while reducing methanol toxicity to enzyme activity. The increase of methanol concentration also increased the FAME yield because it might shift the reaction equilibrium to FAME production. This finding describes that the application of supercritical CO2 in the enzymatic reaction enables the application of simple process such as a packed-bed reactor.

Ramlibacter alkalitolerans sp. nov., alkali-tolerant bacterium isolated from soil of ginseng.

A novel bacterial strain, designated CJ661T, was isolated from soil of ginseng in Anseong, South Korea. Cells of strain CJ661T were white-coloured, Gram-staining-negative, non-motile, aerobic and rod-shaped. Strain CJ661T grew optimally at 30 °C and pH 7.0. The analysis of 16S rRNA gene sequence of strain CJ661T showed that it belongs to the genus Ramlibacter within the family Comamonadaceae and was most closely related to Ramlibacter ginsenosidimutans KCTC 22276T (98.1 %), followed by Ramlibacter henchirensis DSM 14656T (97.1 %). DNA-DNA relatedness levels of strain CJ661T were 40.6 % to R. ginsenosidimutans KCTC 22276T and 25.0 % to R. henchirensis DSM 14656T. The major isoprenoid quinone was ubiquinone (Q-8). The predominant polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The major cellular fatty acids of strain CJ661T were summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), C16 : 0 and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The G+C content of the genomic DNA was 65.4 mol%. On the basis polyphasic taxonomic data, strain CJ661T represents a novel species in the genus Ramlibacter, for which name Ramlibacter alkalitolerans sp. nov. is proposed; the type strain is CJ661T (=KACC 19305T=JCM 32081T).

The Simultaneous Effects of Socioeconomic Disadvantage and Child Health on Children's Cognitive Development.

Family socioeconomic status (SES) and child health are so strongly related that scholars have speculated child health to be an important pathway through which a cycle of poverty is reproduced across generations. Despite increasing recognition that SES and health work reciprocally and dynamically over the life course to produce inequality, research has yet to address how these two pathways simultaneously shape children's development. Using longitudinal data from the Fragile Families and Child Wellbeing Study and marginal structural models, we ask three questions: (1) how does the reciprocal relationship between socioeconomic disadvantage and child health affect estimates of each circumstance on children's cognitive development?; (2) how do their respective effects vary with age?; and (3) do family SES and child health have differential effects on cognitive development across population subgroups? The results show that the negative effects of socioeconomic disadvantage and poor health are insensitive to their reciprocal relationships over time. We find divergent effects of socioeconomic disadvantage and poor health on children's cognitive trajectories, with a widening pattern for family SES effects and a leveling-off pattern for child health effects. Finally, the effects of socioeconomic disadvantage are similar across all racial/ethnic groups, while the effects of child health are largely driven by white children. We discuss theoretical and policy implications of these findings for future research.

MicroRNA signatures associated with thioacetamide-induced liver fibrosis in mice.

Multiple etiologies of liver injury are associated with fibrosis in which the key event is the activation of hepatic stellate cells (HSCs). Although microRNAs (miRNAs) are reportedly involved in fibrogenesis, the complete array of miRNA signatures associated with the disease has yet to be elucidated. Here, deep sequencing analysis revealed that compared to controls, 80 miRNAs were upregulated and 21 miRNAs were downregulated significantly in the thioacetamide (TAA)-induced mouse fibrotic liver. Interestingly, 58 of the upregulated miRNAs were localized to an oncogenic miRNA megacluster upregulated in liver cancer. Differential expression of some of the TAA-responsive miRNAs was confirmed, and their human orthologs were similarly deregulated in TGF-ß1-activated HSCs. Moreover, a functional analysis of the experimentally validated high-confidence miRNA targets revealed significant enrichment for the GO terms and KEGG pathways involved in HSC activation and liver fibrogenesis. This is the first comprehensive report of miRNAs profiles during TAA-induced mouse liver fibrosis.

Flavihumibacter sediminis sp. nov., isolated from tidal flat sediment.

A yellow, Gram-staining-positive, aerobic, rod-shaped and non-motile bacterial strain, designated CJ663T, was isolated from the tidal flat sediment in Ganghwa-do, South Korea. Strain CJ663T grew optimally on R2A at 30 °C and pH 7.0 and did not require NaCl for growth. Phylogenetic analysis based on 16S rRNA gene sequence similarity showed that strain CJ663T belonged to the genus Flavihumibacter within the family Chitinophagaceae and was most closely related to Flavihumibacter cheonanensis KACC 17467T (98.3 % similarity), followed by Flavihumibacter solisilvae KACC 17917T (97.4 %). DNA-DNA relatedness levels of strain CJ663T were 42.9 % to F. cheonanensis KACC 17467T and 48.6 % to F. solisilvae KACC 17917T. The major isoprenoid quinone was menaquinone 7 (MK-7). The predominant polar lipids were phosphatidylethanolamine, aminophospholipid and two unidentified lipids. The major cellular fatty acids of strain CJ663T were iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 0 3-OH. The G+C content of the genomic DNA was 47.7 mol%. On the basis of data from this polyphasic taxonomic study, strain CJ663T represents a novel species in the genus Flavihumibacter, for which name Flavihumibacter sediminis sp. nov. is proposed; the type strain is CJ663T (=KACC 18874T=JCM 31431T).

The Great Recession, genetic sensitivity, and maternal harsh parenting.

Using data from the Fragile Families and Child Wellbeing Study, this study examined the effects of the Great Recession on maternal harsh parenting. We found that changes in macroeconomic conditions, rather than current conditions, affected harsh parenting, that declines in macroeconomic conditions had a stronger impact on harsh parenting than improvements in conditions, and that mothers' responses to adverse economic conditions were moderated by the DRD2 Taq1A genotype. We found no evidence of a moderating effect for two other, less well-studied SNPs from the DRD4 and DAT1 genes.

Air Quality, Biomarker Levels, and Health Effects on Staff in Korean Restaurants and Pubs Before and After a Smoking Ban.

INTRODUCTION: The Korean government implemented a smoking ban at square floor area of ≥150 m(2), rather than <150 m(2), restaurants and pubs from July 2013. This study examined the effects of the smoking regulations in restaurants and pubs in terms of the air quality, biomarker levels and health effects on staff. METHODS: Particulate matter smaller than 2.5 µm (PM2.5) was measured in 146 facilities before and 1 month after the ban. The urinary cotinine and 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanol (NNAL) levels were measured in 101 staff members at 77 facilities before and 1 month after the ban. We also measured self-reported respiratory and sensory symptoms on both phases. RESULTS: Of the 146 facilities, 121 facilities were included in the PM2.5 analysis. In ≥150 m(2) pubs, the indoor PM2.5 concentration was significantly reduced after the ban (p < .05). While the urinary cotinine concentrations of the staff in all facilities were not changed after the ban, the total NNAL concentrations of the staff in ≥150 m(2) pubs were significantly reduced after the ban (p < .05). The health effects on staff show that only sensory symptoms significantly improved in ≥150 m(2) facilities after the ban (p < .05). CONCLUSIONS: The smoking ban significantly reduced the levels of PM2.5 and total NNAL concentrations in ≥150 m(2) pubs and improved sensory health among staff in ≥150 m(2) facilities. The results of this study can be useful in supporting an expansion of the smoking ban in all indoor places, including <150 m(2) restaurants and pubs.

Family Structure Transitions and Child Development: Instability, Selection, and Population Heterogeneity.

A growing literature documents the importance of family instability for child wellbeing. In this article, we use longitudinal data from the Fragile Families and Child Wellbeing Study to examine the impacts of family instability on children's cognitive and socioemotional development in early and middle childhood. We extend existing research in several ways: (1) by distinguishing between the number and types of family structure changes; (2) by accounting for time-varying as well as time-constant confounding; and (3) by assessing racial/ethnic and gender differences in family instability effects. Our results indicate that family instability has a causal effect on children's development, but the effect depends on the type of change, the outcome assessed, and the population examined. Generally speaking, transitions out of a two-parent family are more negative for children's development than transitions into a two-parent family. The effect of family instability is stronger for children's socioemotional development than for their cognitive achievement. For socioemotional development, transitions out of a two-parent family are more negative for white children, whereas transitions into a two-parent family are more negative for Hispanic children. These findings suggest that future research should pay more attention to the type of family structure transition and to population heterogeneity.

The relationship between lifetime health trajectories and socioeconomic attainment in middle age.

A large literature demonstrates the direct and indirect influence of health on socioeconomic attainment, and reveals the ways in which health and socioeconomic background simultaneously and dynamically affect opportunities for attainment and mobility. Despite an increasing understanding of the effects of health on social processes, research to date remains limited in its conceptualization and measurement of the temporal dimensions of health, especially in the presence of socioeconomic circumstances that covary with health over time. Guided by life course theory, we use data from the British National Child Development Study, an ongoing panel study of a cohort born in 1958, to examine the association between lifetime health trajectories and socioeconomic attainment in middle age. We apply finite mixture modeling to identify distinct trajectories of health that simultaneously account for timing, duration and stability. Moreover, we employ propensity score weighting models to account for the presence of time-varying socioeconomic factors in estimating the impact of health trajectories. We find that, when poor health is limited to the childhood years, the disadvantage in socioeconomic attainment relative to being continuously healthy is either insignificant or largely explained by time-varying socioeconomic confounders. The socioeconomic impact of continuously deteriorating health over the life course is more persistent, however. Our results suggest that accounting for the timing, duration and stability of poor health throughout both childhood and adulthood is important for understanding how health works to produce social stratification. In addition, the findings highlight the importance of distinguishing between confounding and mediating effects of time-varying socioeconomic circumstances.

Tolerance for and potential indicators of second-hand smoke exposure among nonsmokers: a comparison of self-reported and cotinine verified second-hand smoke exposure based on nationally representative data.

OBJECTIVE: We assessed the extent to which self-reported exposure to SHS underestimates the actual exposure to SHS and what factors are associated with a tolerance for SHS exposure in the Korean setting where the smoke-free policy is incomplete. METHODS: Information on socio-demographic characteristics, alcohol drinking and smoking was collected for 7948 nonsmokers aged ≥ 19 years from the fourth Korea National Health and Nutrition Examination Survey, 2008-2009. Self-reported and cotinine verified SHS exposures were compared. Potential factors associated with cotinine verified but not self-reported SHS exposures were assessed using a logistic regression model. RESULTS: Self-reported SHS exposure significantly underestimated the actual SHS exposure as determined by cotinine verification (kappa coefficient: 0.1066). At younger age, frequent alcohol drinking in females and a longer smoking duration in males were positively associated with cotinine verified exposure but not with the self-reported SHS exposure; they were also positively associated with cotinine verified exposure irrespective of self-reported SHS exposure. CONCLUSIONS: Our findings show a tolerance for smoking in Korea. The current partial ban on smoking does not fully protect people from exposure to SHS. Smoking should be banned in all public places. In addition, efforts to de-normalize smoking in the Korean culture need to be strengthened.