Family ideals in an era of low fertility.

Taking stock of individuals' perceived family ideals is particularly important in the current moment given unprecedented fertility declines and the diversification of households in advanced industrial societies. Study participants in urban China, Japan, South Korea, Singapore, the United States, Italy, Spain, and Norway were asked to evaluate vignettes describing families whose characteristics vary on ten dimensions. In contrast to previous studies that focused on a single dimension, such as fertility ideals or gender roles, this holistic vignette approach identifies the relative importance of each dimension. Multilevel regression analysis reveals both expected and unexpected findings. Parenthood remains a positive ideal, but the number of children does not matter once other family dimensions are considered, a potentially important finding in light of conventional wisdom regarding the two-children ideal. When evaluating families with at least one child, respondents tend to positively evaluate more traditional arrangements, including valuing marriage relative to cohabitation and, particularly, divorce. Also, in addition to financial resources, good communication between immediate and extended family members, as well as maintaining respect in the larger community, are highly salient attributes of an ideal family. Notwithstanding some important cross-national differences, egalitarian gender roles and avoiding work-family conflict are also valued positively. Overall, even as the study reveals some notable variations between societies, respondents across countries identify similar components of an ideal family.

Biological invasion with a porous medium type diffusion in a heterogeneous space.

The knowledge of traveling wave solutions is the main tool in the study of wave propagation. However, in a spatially heterogeneous environment, traveling wave solutions do not exist, and a different approach is needed. In this paper, we study the generation and the propagation of hyperbolic scale singular limits of a KPP-type reaction-diffusion equation when the carrying capacity is spatially heterogeneous and the diffusion is of a porous medium equation type. We show that the interface propagation speed varies according to the carrying capacity.

Two putative probiotic strains improve diet-induced hypercholesterolemia through modulating intestinal cholesterol uptake and hepatic cholesterol efflux.

AIMS: Two putative probiotic strains, Lacticaseibacillus (Lc.) rhamnosus BFE5264 and Lactiplantibacillus (Lp.) plantarum NR74, have been shown to suppress cholesterol uptake and promote cholesterol efflux in Caco-2 cells. However, an in vivo beneficial effect of these strains on plasma cholesterol levels has not been verified yet; neither have the underlying mechanisms of regulating cholesterol metabolism clarified thus far. This study has focused on these two aspects. METHODS AND RESULTS: A murine model has been used, and the animals receiving a high-fat/high-cholesterol diet showed elevated plasma cholesterol levels. However, supplementation of Lc. rhamnosus BFE5264 and Lp. plantarum NR74 resulted in the down regulation of Niemann-Pick C1-like 1 (NPC1L1) in the intestine in addition to counteracting the diet-induced suppression of low-density lipoprotein receptor expression in the liver. ATP Binding Cassette Subfamily A Member 1 (ABCA1) was only significantly increased upon administration of Lc. rhamnosus BFE5264. CONCLUSIONS: The present findings demonstrate that supplementation with Lc. rhamnosus BFE5264 and Lp. plantarum NR74 may improve diet-induced hypercholesterolemia by suppression of cholesterol absorption in the small intestine and by supporting the regulation of cholesterol metabolism in the liver. SIGNIFICANCE AND IMPACT OF THE STUDY: This work contributes to understanding the beneficial effects of probiotics on host cholesterol metabolism and underlying mechanisms related to hypercholesterolemia.

Compressed Deep Learning to Classify Arrhythmia in an Embedded Wearable Device.

The importance of an embedded wearable device with automatic detection and alarming cannot be overstated, given that 15-30% of patients with atrial fibrillation are reported to be asymptomatic. These asymptomatic patients do not seek medical care, hence traditional diagnostic tools including Holter are not effective for the further prevention of associated stroke or heart failure. This is likely to be more so in the era of COVID-19, in which patients become more reluctant on hospitalization and checkups. However, little literature is available on this important topic. For this reason, this study developed efficient deep learning with model compression, which is designed to use ECG data and classify arrhythmia in an embedded wearable device. ECG-signal data came from Korea University Anam Hospital in Seoul, Korea, with 28,308 unique patients (15,412 normal and 12,896 arrhythmia). Resnets and Mobilenets with model compression (TensorFlow Lite) were applied and compared for the diagnosis of arrhythmia in an embedded wearable device. The weight size of the compressed model registered a remarkable decrease from 743 MB to 76 KB (1/10000), whereas its performance was almost the same as its original counterpart. Resnet and Mobilenet were similar in terms of accuracy, i.e., Resnet-50 Hz (97.3) vs. Mo-bilenet-50 Hz (97.2), Resnet-100 Hz (98.2) vs. Mobilenet-100 Hz (97.9). Here, 50 Hz/100 Hz denotes the down-sampling rate. However, Resnets took more flash memory and longer inference time than did Mobilenets. In conclusion, Mobilenet would be a more efficient model than Resnet to classify arrhythmia in an embedded wearable device.

Diverging gaps in childcare time by parental education in South Korea.

BACKGROUND: Parental time is a key resource for children's development. Studies in the United States highlight diverging gaps in parental time for children between highly educated and low-educated parents. South Korea offers an interesting context in which to examine the trend. OBJECTIVE: This study assesses whether differences in childcare time have diverged or converged between parents with higher and lower levels of education over the 15-year period. Utilizing the advantage of household survey, the total amount of childcare time spent by both fathers and mothers is examined, in addition to separate time for each parent. METHODS: The Korean Time Use Surveys (KTUS), conducted in 1999, 2004, 2009, and 2014, provide time diary data for two consecutive days. OLS regression models are applied to 14,044 married mothers and fathers who have at least one child under school age in order to examine how educational differences in childcare time have changed across the four surveys. RESULTS: The OLS results show that both mothers and fathers have spent increasingly more time for childcare between 1999 and 2014, regardless of educational levels. However, the rise of time use is more substantial among mothers and fathers with a university degree than their counterparts with high school or less education. The diverging trend is even more evident for the combined childcare time spent by both mothers and fathers. CONTRIBUTION: The divergence in childcare time by parental education is consistent with emerging trends of growing educational gaps in family behavior in Korea, raising the concern for diverging destinies between advantaged and disadvantaged children.

Introduction to the special collection on family changes and inequality in East Asia.

BACKGROUND: East Asian societies have experienced rapid social changes, among which the extraordinary expansion of higher education for both women and men, rising economic inequality, and increasing labor market uncertainty should be particularly relevant to family changes. At the same time, gender inequality and traditional gender norms still prevail and shape family life in the region. The eight articles in this special collection share the common interest of how families in East Asia have evolved against a backdrop of growing economic inequality and persistent gender inequality - among other key forces affecting family life - across a variety of family-related outcomes: from singlehood, marriage intentions, and dating, through fertility, the time use of adolescents and parents with young children, and women's careers, to intergenerational coresidence and the life satisfaction of older parents. RESULTS: Our eight studies look at connected but distinctive outcomes related to family life, and collectively demonstrate the relevance of increased labor market uncertainty and the continuing male breadwinner norm to emerging patterns of family behavior in East Asia. They illustrate specific ways in which East Asian families are shaped by the joint forces of economic inequality and gender inequality. CONTRIBUTION: This volume highlights the complexity and heterogeneity of contemporary East Asian families, inviting family and demography researchers to conduct more studies on under-researched family behaviors such as cohabitation and nonmarital births and to revisit the conventional perception that family ties are strong and family support is readily available in East Asia.

Marriage Decline in Korea: Changing Composition of the Domestic Marriage Market and Growth in International Marriage.

Explanations for the substantial decline in rates of marriage in East Asian countries often emphasize the role of rapid educational expansion for women in reducing the desirability of marriages characterized by a strong gender-based division of labor. Focusing on South Korea, we consider a very different scenario in which changing educational composition of the marriage market reduces the demographic feasibility of such marriages. Analyses of 1% microsamples of the 1990 and 2010 Korean censuses show that changes in the availability of potential spouses accounted for part of the decline in marriage rates over a period of 20 years (1985-1989 to 2005-2009) for highly educated women and less-educated men. We also show that growth in international marriages played a role in preventing an even more dramatic decline in marriage among low-educated men. These findings support the general relevance of marriage market mismatches in gender-inegalitarian societies and highlight the declining feasibility of marriage for low-educated men in such contexts. Findings also hint at important implications for inequality in a society such as Korea, where marriage remains a symbol of social success and is closely related to women's economic well-being and men's health and subjective well-being.

Educational expansion and trends in intergenerational social mobility among Korean men.

Scholars have explored three channels through which educational expansion contributes to increased intergenerational social mobility: the compositional effect, educational equalization, and class returns to education. Existing literature on impacts of educational expansion on intergenerational social mobility is primarily based on experiences of European societies and the United States. We expand the existing literature by investigating the relationship between educational expansion and intergenerational mobility in Korea showing an exceptional degree of educational expansion over the last few decades. Log-linear models show that social fluidity has increased across birth cohorts of Korean men born between 1950 and 1984, with the recent cohorts experiencing it considerably. Utilizing a counterfactual decomposition method, our study shows that educational expansion has played a crucial role in promoting social fluidity mainly through educational equalization for earlier cohorts and through the compositional effect for more recent cohorts. The role played by the class returns to education was minor.

Do Single-Sex Schools Enhance Students' STEM (Science, Technology, Engineering, and Mathematics) Outcomes?

In many countries, males currently lag behind females in schooling attainment but females are still underrepresented in STEM studies. This pattern has raised renewed interest in the potential of single-sex schools for enhancing STEM outcomes. Utilizing the unique setting in Seoul, where assignment to single-sex or coeducational high schools is random, and with multiple years of administrative data from the national college entrance examinations and a longitudinal survey of high school seniors, we assess causal effects of single-sex schools on students' math test scores and choice of the science-math test. We also assess whether single-sex schools affect students' interests and self-efficacy in math and science, and expectations and actual choices of a STEM college major in university. We find significantly positive effects of all-boys schools consistently across different STEM outcomes but not for girls. We address one possible mechanism by conducting mediation analysis with the proportion of same-gender math teachers.

The catalytic activity of a recombinant single chain variable fragment nucleic acid-hydrolysing antibody varies with fusion tag and expression host.

The antigen-binding properties of single chain Fv antibodies (scFvs) can vary depending on the position and type of fusion tag used, as well as the host cells used for expression. The issue is even more complicated with a catalytic scFv antibody that binds and hydrolyses a specific antigen. Herein, we investigated the antigen-binding and -hydrolysing activities of the catalytic anti-nucleic acid antibody 3D8 scFv expressed in Escherichia coli or HEK293f cells with or without additional amino acid residues at the N- and C-termini. DNA-binding activity was retained in all recombinant forms. However, the DNA-hydrolysing activity varied drastically between forms. The DNA-hydrolysing activity of E. coli-derived 3D8 scFvs was not affected by the presence of a C-terminal human influenza haemagglutinin (HA) or His tag. By contrast, the activity of HEK293f-derived 3D8 scFvs was completely lost when additional residues were included at the N-terminus and/or when a His tag was incorporated at the C-terminus, whereas a HA tag at the C-terminus did not diminish activity. Thus, we demonstrate that the antigen-binding and catalytic activities of a catalytic antibody can be separately affected by the presence of additional residues at the N- and C-termini, and by the host cell type.

Lactobacillus plantarum HAC01 regulates gut microbiota and adipose tissue accumulation in a diet-induced obesity murine model.

The functional features of Lactobacillus plantarum HAC01 (HAC01), isolated from fermented Korean kimchi, were studied with regard to the fat mass, immunometabolic biomarkers and dysbiosis in a diet-induced obesity (DIO) murine model. L. rhamnosus GG (LGG) served as reference strain and a PBS-treated group as control. The administration of L. plantarum HAC01 resulted in reduction of the mesenteric adipose depot, the conjunctive tissue closely associated with the gastrointestinal tract, where lipid oxidative gene expression was upregulated compared to the control group. Metagenome analysis of intestinal microbiota showed that both strains HAC01 and LGG influenced specific bacterial families such as the Lachnospiraceae and Ruminococcaceae rather than the phyla Firmicutes and Bacteroidetes as a whole. The relative abundance of the Lachnospiraceae (phylum Firmicutes) was significantly higher in both LAB-treated groups than in the control. Comparing the impact of the two Lactobacillus strains on microbial composition in the gut also suggests strain-specific effects. The study emphasises the need for deeper studies into functional specificity of a probiotic organism at the strain level. Alleviation of obesity-associated dysbiosis by modulation of the gut microbiota appears to be associated with "indicator" bacterial taxa such as the family Lachnospiraceae. This may provide further insight into mechanisms basic to the mode of probiotic action against obesity and associated dysbiosis.

Growing educational differentials in the retreat from marriage among Korean men.

Applying discrete-time hazard models to person-year data constructed from 1% microdata sample of 2010 Korean Census, we explore how men's education affects their transition to first marriage, and how the relationship between education and marriage has changed across three 10-year birth cohorts of Korean men born from 1946 to 1975. Drawing on Oppenheimer's theory of marriage and review of changing educational and economic contexts of Korean men, we develop a hypothesis on growing educational differentials in marriage. We find that the high educated delay marriage until later ages but catch up to the extent to which they are eventually more likely to marry than the low educated. There is a continued trend across cohorts toward the delay and avoidance of marriage at all educational levels. However, the trend of retreat from marriage has been more substantial for men with high school or less education compared to men with a university degree, leading to growing educational gaps over time in marriage. Among the three cohorts, the youngest cohort, among which low educated men's economic prospects have particularly deteriorated due to rapid educational expansion and economic crisis, shows most pronounced decline in marriage.

When Different Types of Education Matter: Effectively Maintained Inequality of Educational Opportunity in Korea.

Using longitudinal data for a nationally representative sample of ninth graders in South Korea, we examine socioeconomic differences in the likelihood of making transitions into different types of high school and college with a goal of testing the validity of the Effectively Maintained Inequality (EMI) hypothesis. We find significant socioeconomic disparities in the likelihood of attending an academic high school and a four-year university. However, the predicted probabilities suggest that even disadvantaged students typically choose academic high school relative to vocational high school. Further, although disadvantaged students likely end up with a two-year junior college, those disadvantaged students graduating from an academic high school typically choose a four-year university, after controlling for academic achievement and other variables. We discuss the relevance of EMI for South Korea and broad implications for elsewhere where postsecondary education becomes close to be universal.

Development of putative probiotics as feed additives: validation in a porcine-specific gastrointestinal tract model.

Enforced restrictions on the use of antibiotics as growth promoters (AGPs) in animal production have prompted investigations into alternative feed additives in recent decades. Probiotics are currently the main feed additive used in livestock. However, the selection of probiotic candidates relies on human-based methods and little is known about the verification criteria for host-specific selection. We investigated the probiotic potential of Lactobacillus salivarius strains isolated from fed pig feces for their use as porcine feed additives. Two methods were developed that simulated the pig gastrointestinal (GI) tract and the intestinal epithelium, and these were compared with human-based in vitro methods and used for selecting porcine probiotics. Lactobacillus salivarius strain LS6 was identified as a promising probiotic strain for potential use as a porcine feed additive. This strain prevented disruption of the epithelial integrity of pig small intestine (PSI) cells by inhibiting the adherence of enterotoxigenic Escherichia coli K88. It also showed high survival rates in the in vitro pig GI tract model and good adhesion to PSI cells. We propose that host target-specific screening and validation methods are important tools in the development of effective probiotic feed additives, and this approach may support future-oriented agriculture.

Analysis of coordination between thoracic and pelvic kinematic movements during gait in adolescents with idiopathic scoliosis.

PURPOSE: In this research, we investigated the coordination pattern and consistency of coordination between the thorax and pelvis during gait in patients with idiopathic scoliosis. METHODS: Across the study, 69 adolescent girls (controls: 30, patients: 39) participated. All participants were asked to walk 10 m barefoot at a self-selected speed. The walking speed, stride length, and range of motion of the pelvic and thoracic angles were collected using a three-dimensional optical motion analysis system, and the thorax-pelvis coordination was quantified using a vector coding technique. The frequency of four different patterns of coordination (in-phase, anti-phase, pelvis only, and thorax only) and the consistency of coordination including direction and magnitude during the gait cycle of the two groups were investigated. Independent-sample t tests were performed to examine differences between the two groups with regard to coordination patterns and consistency. RESULTS: The patients with idiopathic scoliosis showed significantly higher in-phase and relatively lower anti-phase in the transverse plane compared to controls. Additionally, the pelvis only in the transverse, frontal, and sagittal planes was significantly lower in patients. The consistency of coordination in patients was significantly lower than in controls in direction and magnitude on the transverse and frontal planes. CONCLUSION: From viewpoint of the thorax-pelvis coordination, patients with IS had less gait stability in the trunk than controls.

Kinematic relationship between rotation of lumbar spine and hip joints during golf swing in professional golfers.

BACKGROUND: Understanding the kinematics of the lumbar spine and hip joints during a golf swing is a basic step for identifying swing-specific factors associated with low back pain. The objective of this study was to examine the kinematic relationship between rotational movement of the lumbar spine and hip joints during a golf swing. METHODS: Fifteen professional golfers participated in this study with employment of six infrared cameras to record their golf swings. Anatomical reference system of the upper torso, pelvis and thigh segments, and the location of each hip and knee joint were defined by the protocols of the kinematic model of previous studies. Lumbar spine and hip joint rotational angle was calculated utilizing the Euler angle method. Cross-correlation and angle-angle plot was used to examine the degree of kinematic relationship between joints. RESULTS: A fairly strong coupling relationship was shown between the lumbar spine and hip rotational movements with an average correlation of 0.81. Leading hip contribution to overall rotation was markedly high in the early stage of the downswing, while the lumbar spine contributed greater towards the end of the downswing; however, the relative contributions of the trailing hip and lumbar spine were nearly equal during the entire downswing. CONCLUSIONS: Most of the professional golfers participated in this study used a similar coordination strategy when moving their hips and lumbar spine during golf swings. The rotation of hips was observed to be more efficient in producing the overall rotation during the downswing when compared to the backswing. These results provide quantitative information to better understand the lumbar spine and hip joint kinematic characteristics of professional golfers. This study will have great potential to be used as a normal control data for the comparison with kinematic information among golfers with low back pain and for further investigation of golf swing-specific factors associated with injury.

Outcomes of acute kidney injury patients with and without cancer.

Incidence of AKI in hospitalized patients with cancer is increasing, but there have been few studies on AKI in patients with cancer. We conducted a retrospective cohort study in a South Korean tertiary care hospital. A total of 2211 consecutive patients (without cancer 61.5%; with cancer 38.5%) were included over a 140-month period. Predictors of all-cause death were examined using the Kaplan-Meier method and the Cox proportional hazards model. The main contributing factors of AKI were sepsis (31.1%) and ischemia (52.7%). AKI was multifactorial in 78% of patients with cancer and in 71% of patients without cancer. Hospital mortality rates were higher in patients with cancer (42.8%) than in patients without cancer (22.5%) (p = 0.014). In multivariate analyses, diabetes mellitus (DM) and cancer diagnosis were associated with hospital mortality. Cancer diagnosis was independently associated with mortality [odds ratio = 3.010 (95% confidence interval, 2.340-3.873), p = 0.001]. Kaplan-Meier analysis revealed that subjects with DM and cancer (n = 146) had lower survival rates than subjects with DM and without cancer (n = 687) (log rank test, p = 0.001). The presence of DM and cancer was independently associated with mortality in AKI patients both with and without cancer. Studies are warranted to determine whether proactive measures may limit AKI and improve outcomes.

Do grandparents matter? A multigenerational perspective on educational attainment in Taiwan.

In response to the growing interest in multigenerational effects, we investigate whether grandparents' education affects grandchildren's transitions to academic high school and university in Taiwan. Drawing on social capital literature, we consider potential heterogeneity of the grandparent effect by parents' characteristics and propose that grandparents' education yields differential effects depending on parents' education. Our results show tenuous effects of grandmother's and grandfather's years of schooling, net of parents' education. However, the positive interaction effects between grandparents' and parents' years of schooling indicate that grandparents' additional years of schooling are more beneficial to students with more educated parents than for students with less educated parents. The diverging gap in the likelihood of attending academic high school or university between students with parents in higher and lower ends of the educational hierarchy, along with increased levels of grandparents' education, supports our hypothesis that grandparents' education augments educational inequality by parents' education.

Reduction in cholesterol absorption in Caco-2 cells through the down-regulation of Niemann-Pick C1-like 1 by the putative probiotic strains Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 from fermented foods.

Hypercholesterolaemia is a major risk factor related to atherosclerosis, and it may be influenced by our diet. This study addresses the impact of Lactobacillus rhamnosus BFE5264 (isolated from Maasai fermented milk) and Lactobacillus plantarum NR74 (from Korean kimchi) on the control of cholesterol absorption through down-regulation of Niemann-Pick C1-like 1 (NPC1L1) expression. Caco-2 enterocytes were treated with the live, heat-killed (HK) bacteria, bacterial cell wall extracts and metabolites; mRNA level and protein expression were measured. Caco-2 cells showed lower NPC1L1 expression in the presence of the live test strains than the control, elucidating down-regulation of cholesterol uptake, and were compared well with the positive control, L. rhamnosus GG. This effect was also observed with HK bacteria and cell wall fractions but not with their metabolites. The potential of some Lactobacillus strains associated with traditional fermented foods to suppress cholesterol uptake and promote its efflux in enterocytes has been suggested from these data.

The probiotic Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 promote cholesterol efflux and suppress inflammation in THP-1 cells.

BACKGROUND: The balance between the rate of cholesterol uptake/accumulation and the rate of cholesterol efflux is reflected in the amount of lipid accumulation in macrophages. Based upon the fact that liver X receptors (LXRs) play a role in cholesterol efflux, we studied the effects of probiotics on cholesterol efflux and anti-inflammatory action in macrophages. We confirmed changes in LXR expression by treatment of LXR-transfected CHO-K1 cells with lactic acid bacteria (LAB), and co-cultured THP-1 cells with LAB to investigate changes in cholesterol efflux and inflammation. RESULTS: The experiment with CHO-K1 cells showed upregulation of LXR-ß by LAB. Treatment of THP-1 cells with LAB promoted LXR expression in THP-1, which eventually led to significant upregulation of ABCA1 and ABCG1 expression. The treatment with live LAB also significantly promoted cholesterol efflux. LAB suppressed expression of interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, which resulted from activation of LXR. CONCLUSION: Our study shows that Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 activated LXR and induced cholesterol efflux by promoting expression of ABCA1 and ABCG1. Both strains also suppressed proinflammatory cytokines including IL-1ß and TNF-α. This study could account for the observation that LAB may block foam cell formation by cholesterol efflux and immune modulation.