Assessing the Independent Contribution of Maternal Educational Expectations to Children’s Educational Attainment in Early Adulthood: A Propensity Score Matching Analysis

Background

Parental educational expectations have been associated with children’s educational attainment in a number of long-term longitudinal studies, but whether this relationship is causal has long been debated. The aims of this prospective study were twofold: 1) test whether low maternal educational expectations contributed to failure to graduate from high school; and 2) compare the results obtained using different strategies for accounting for confounding variables (i.e. multivariate regression and propensity score matching).

Methodology/Principal Findings

The study sample included 1,279 participants from the Quebec Longitudinal Study of Kindergarten Children. Maternal educational expectations were assessed when the participants were aged 12 years. High school graduation – measuring educational attainment – was determined through the Quebec Ministry of Education when the participants were aged 22–23 years. Findings show that when using the most common statistical approach (i.e. multivariate regressions to adjust for a restricted set of potential confounders) the contribution of low maternal educational expectations to failure to graduate from high school was statistically significant. However, when using propensity score matching, the contribution of maternal expectations was reduced and remained statistically significant only for males.

Conclusions/Significance

The results of this study are consistent with the possibility that the contribution of parental expectations to educational attainment is overestimated in the available literature. This may be explained by the use of a restricted range of potential confounding variables as well as the dearth of studies using appropriate statistical techniques and study designs in order to minimize confounding. Each of these techniques and designs, including propensity score matching, has its strengths and limitations: A more comprehensive understanding of the causal role of parental expectations will stem from a convergence of findings from studies using different techniques and designs.     

A Statistical Method of Identifying Interactions in Neuron–Glia Systems Based on Functional Multicell Ca2+ Imaging

Crosstalk between neurons and glia may constitute a significant part of information processing in the brain. We present a novel method of statistically identifying interactions in a neuron–glia network. We attempted to identify neuron–glia interactions from neuronal and glial activities via maximum-a-posteriori (MAP)-based parameter estimation by developing a generalized linear model (GLM) of a neuron–glia network. The interactions in our interest included functional connectivity and response functions. We evaluated the cross-validated likelihood of GLMs that resulted from the addition or removal of connections to confirm the existence of specific neuron-to-glia or glia-to-neuron connections. We only accepted addition or removal when the modification improved the cross-validated likelihood. We applied the method to a high-throughput, multicellular in vitro Ca2+ imaging dataset obtained from the CA3 region of a rat hippocampus, and then evaluated the reliability of connectivity estimates using a statistical test based on a surrogate method. Our findings based on the estimated connectivity were in good agreement with currently available physiological knowledge, suggesting our method can elucidate undiscovered functions of neuron–glia systems.     

Health Behaviors of Korean Gastric Cancer Survivors with Hypertension: A Propensity Analysis of KNHANES III-V (2005–2012)

ObjectiveThis study provides a comparison of health behaviors between gastric cancer survivors with hypertension and non-cancer subjects in Korea.MethodsData from the Korean National Health and Nutrition Examination Survey (KNHANES) for the period of 2005-2012 were used in this study. A propensity score matching method was used to compare health behaviors. Before the matching of propensity scores, the number of participants was 11034 (102 gastric cancer survivors and 10932 non-cancer participants). A 1:5 propensity score matching procedure yielded a total of 480 participants (80 gastric cancer survivors and 400 non-cancer participants) for the final analysis. Drinking, smoking, physical activity, antihypertensive medication adherence, self-reported diet control, and sodium intake accordance in the two groups were compared. A complex samples logistic regression analysis was conducted to assess any differences between the two groups.ResultsThe group of hypertensive gastric cancer survivors had lower alcohol consumption (OR = 0.30; 95% CI: 0.14-0.66; p-value = 0.003). They were more likely to be on dietary control than the control group (OR = 3.12; 95% CI: 1.60-6.10; p-value = 0.001). However, there was no significant (p > 0.05) difference in sodium intake accordance or other health behaviors (including medication adherence, smoking, and physical activity) between the two groups.ConclusionsOur results revealed that gastric cancer survivors with hypertension were more likely to be on dietary control with lower alcohol consumption than the control group. However, there was no significant difference in sodium intake accordance or other health behaviors between the two groups. Therefore, primary care physicians should inform cancer survivors about the appropriate health behaviors to reduce their risk of cardiovascular disease and improve their overall survival rate, even though they say they have been doing health behaviors.     

Effects of Hydroxylated Carbon Nanotubes on the Aggregation of Aβ16–22 Peptides: A Combined Simulation and Experimental Study

The pathogenesis of Alzheimer’s disease (AD) is associated with the aggregation of amyloid-β (Aβ) peptides into toxic aggregates with β-sheet character. In a previous computational study, we showed that pristine single-walled carbon nanotubes (SWCNTs) can inhibit the formation of β-sheet-rich oligomers in the central hydrophobic core fragment of Aβ (Aβ_16–22). However, the poor solubility of SWCNTs in water hinders their use in biomedical applications and nanomedicine. Here, we investigate the influence of hydroxylated SWCNT, a water-soluble SWCNT derivative, on the aggregation of Aβ_16–22 peptides using all-atom explicit-water replica exchange molecular dynamics simulations. Our results show that hydroxylated SWCNTs can significantly inhibit β-sheet formation and shift the conformations of Aβ_16–22 oligomers from ordered β-sheet-rich structures toward disordered coil aggregates. Detailed analyses of the SWCNT-Aβ interaction reveal that the inhibition of β-sheet formation by hydroxylated SWCNTs mainly results from strong electrostatic interactions between the hydroxyl groups of SWCNTs and the positively charged residue K16 of Aβ_16–22 and hydrophobic and aromatic stacking interactions between SWCNTs and F19 and F20. In addition, our atomic force microscopy and thioflavin T fluorescence experiments confirm the inhibitory effect of both pristine and hydroxylated SWCNTs on Aβ_16–22 fibrillization, in support of our previous and present replica exchange molecular dynamics simulation results. These results demonstrate that hydroxylated SWCNTs efficiently inhibit the aggregation of Aβ_16–22; in addition, they offer molecular insight into the inhibition mechanism, thus providing new clues for the design of therapeutic drugs against amyloidosis.     

Cooperation without Culture? The Null Effect of Generalized Trust on Intentional Homicide: A Cross-National Panel Analysis, 1995–2009

Sociologists, political scientists, and economists all suggest that culture plays a pivotal role in the development of large-scale cooperation. In this study, I used generalized trust as a measure of culture to explore if and how culture impacts intentional homicide, my operationalization of cooperation. I compiled multiple cross-national data sets and used pooled time-series linear regression, single-equation instrumental-variables linear regression, and fixed- and random-effects estimation techniques on an unbalanced panel of 118 countries and 232 observations spread over a 15-year time period. Results suggest that culture and large-scale cooperation form a tenuous relationship, while economic factors such as development, inequality, and geopolitics appear to drive large-scale cooperation.     

Phylogenetic Analysis of Vertically Transmitted Psyllid Endosymbionts (Candidatus Carsonella ruddii) Based on atpAGD and rpoC: Comparisons with 16S–23S rDNA-Derived Phylogeny

Psyllids are insects that harbor endosymbionts (Candidatuus Carsonella ruddii) within specialized cells found in the insect's body cavity. Previous phylogenetic analyses based on endosymbiont 16S–23S ribosomal DNA and a host gene were concordant (M.L. Thao, et al., Appl. Env. Microbiol. 66:2898, 2000). Additional analyses with atpAGD and rpoBC gave similar trees showing the agreement expected from organisms that evolve through vertical transmission with no gene exchange. Received: 2 November 2000 / Accepted: 17 November 2000     

Pastoralism in Northern Peru during Pre-Hispanic Times: Insights from the Mochica Period (100–800 AD) Based on Stable Isotopic Analysis of Domestic Camelids

Llama (Lama glama) and alpaca (Vicugna pacos) are the only large domesticated animals indigenous to the Americas. Pastoralism occupies a fundamental economic, social and religious role in Andean life. Today, camelid livestock are confined to the ecozone of the puna (above 3,500 masl), while their presence on the Pacific coast during pre-Hispanic times is attested by archaeological skeletal remains. This study aims to document herding practices on the northern Peruvian coast during the Early Intermediate Period (200 BC-600 AD) by gaining insights into diet, location of breeding and mobility of archaeological camelids from the funerary and ritual contexts of two Mochica sites, Uhle Platform in Huacas de Moche and El Brujo. The three first early years and the long-term life histories of the animals were documented by the combined bulk analysis of bone collagen (δ¹³C_col and δ¹⁵N_col) and bone structural carbonate (δ¹³C_bone and δ¹⁸O_bone) and the serial analysis of structural carbonate of molar tooth enamel (δ¹³C_enamel and δ¹⁸O_enamel). Mochica camelids were bred in the low and/or middle valleys, unlike their modern counterparts, who are restricted to highland puna C₃ pastures. Archaeological camelids had diverse and complex life histories, usually with substantial maize foddering. An ontogenetic switch in diet and possible residential mobility during the course of life were identified for some specimens. Although the inference of geographic origin from δ¹⁸O_bone and δ¹⁸O_enamel values was limited because of the lack of understanding of the influence of environmental and biological factors, tooth enamel analysis has great potential for exploring camelid herding practices and Andean pastoralism. Our study suggested that Mochica herders adapted their practices to the difficult lowland environment and that herding practices were varied and not restricted to breeding at higher altitudes. The role of maize in different aspects of the economic life of the Mochicas is also underlined.     

Why Children with Severe Bacterial Infection Die: A Population–Based Study of Determinants and Consequences of Suboptimal Care with a Special Emphasis on Methodological Issues

Introduction

Suboptimal care is frequent in the management of severe bacterial infection. We aimed to evaluate the consequences of suboptimal care in the early management of severe bacterial infection in children and study the determinants.

Methods

A previously reported population-based confidential enquiry included all children (3 months- 16 years) who died of severe bacterial infection in a French area during a 7-year period. Here, we compared the optimality of the management of these cases to that of pediatric patients who survived a severe bacterial infection during the same period for 6 types of care: seeking medical care by parents, evaluation of sepsis signs and detection of severe disease by a physician, timing and dosage of antibiotic therapy, and timing and dosage of saline bolus. Two independent experts blinded to outcome and final diagnosis evaluated the optimality of these care types. The effect of suboptimal care on survival was analyzed by a logistic regression adjusted on confounding factors identified by a causal diagram. Determinants of suboptimal care were analyzed by multivariate multilevel logistic regression.

Results

Suboptimal care was significantly more frequent during early management of the 21 children who died as compared with the 93 survivors: 24% vs 13% (p = 0.003). The most frequent suboptimal care types were delay to seek medical care (20%), under-evaluation of severity by the physician (20%) and delayed antibiotic therapy (24%). Young age (under 1 year) was independently associated with higher risk of suboptimal care, whereas being under the care of a paediatric emergency specialist or a mobile medical unit as compared with a general practitioner was associated with reduced risk.

Conclusions

Suboptimal care in the early management of severe bacterial infection had a global independent negative effect on survival. Suboptimal care may be avoided by better training of primary care physicians in the specifics of pediatric medicine.     

Molecular Evolutionary Analysis of the Influenza A(H1N1)pdm,May–September, 2009: Temporal and Spatial Spreading Profile of the Viruses in Japan

Background

In March 2009, pandemic influenza A(H1N1) (A(H1N1)pdm) emerged in Mexico and the United States. In Japan, since the first outbreak of A(H1N1)pdm in Osaka and Hyogo Prefectures occurred in the middle of May 2009, the virus had spread over 16 of 47 prefectures as of June 4, 2009.

Methods/Principal Findings

We analyzed all-segment concatenated genome sequences of 75 isolates of A(H1N1)pdm viruses in Japan, and compared them with 163 full-genome sequences in the world. Two analyzing methods, distance-based and Bayesian coalescent MCMC inferences were adopted to elucidate an evolutionary relationship of the viruses in the world and Japan. Regardless of the method, the viruses in the world were classified into four distinct clusters with a few exceptions. Cluster 1 was originated earlier than cluster 2, while cluster 2 was more widely spread around the world. The other two clusters (clusters 1.2 and 1.3) were suggested to be distinct reassortants with different types of segment assortments. The viruses in Japan seemed to be a multiple origin, which were derived from approximately 28 transported cases. Twelve cases were associated with monophyletic groups consisting of Japanese viruses, which were referred to as micro-clade. While most of the micro-clades belonged to the cluster 2, the clade of the first cases of infection in Japan originated from cluster 1.2. Micro-clades of Osaka/Kobe and the Fukuoka cases, both of which were school-wide outbreaks, were eradicated. Time of most recent common ancestor (tMRCA) for each micro-clade demonstrated that some distinct viruses were transmitted in Japan between late May and early June, 2009, and appeared to spread nation-wide throughout summer.

Conclusions

Our results suggest that many viruses were transmitted from abroad in late May 2009 irrespective of preventive actions against the pandemic influenza, and that the influenza A(H1N1)pdm had become a pandemic stage in June 2009 in Japan.     

Effects of Hydroxylated Carbon Nanotubes on the Aggregation of Aβ16–22 Peptides: A Combined Simulation and Experimental Study

The pathogenesis of Alzheimer’s disease (AD) is associated with the aggregation of amyloid-β (Aβ) peptides into toxic aggregates with β-sheet character. In a previous computational study, we showed that pristine single-walled carbon nanotubes (SWCNTs) can inhibit the formation of β-sheet-rich oligomers in the central hydrophobic core fragment of Aβ (Aβ_16–22). However, the poor solubility of SWCNTs in water hinders their use in biomedical applications and nanomedicine. Here, we investigate the influence of hydroxylated SWCNT, a water-soluble SWCNT derivative, on the aggregation of Aβ_16–22 peptides using all-atom explicit-water replica exchange molecular dynamics simulations. Our results show that hydroxylated SWCNTs can significantly inhibit β-sheet formation and shift the conformations of Aβ_16–22 oligomers from ordered β-sheet-rich structures toward disordered coil aggregates. Detailed analyses of the SWCNT-Aβ interaction reveal that the inhibition of β-sheet formation by hydroxylated SWCNTs mainly results from strong electrostatic interactions between the hydroxyl groups of SWCNTs and the positively charged residue K16 of Aβ_16–22 and hydrophobic and aromatic stacking interactions between SWCNTs and F19 and F20. In addition, our atomic force microscopy and thioflavin T fluorescence experiments confirm the inhibitory effect of both pristine and hydroxylated SWCNTs on Aβ_16–22 fibrillization, in support of our previous and present replica exchange molecular dynamics simulation results. These results demonstrate that hydroxylated SWCNTs efficiently inhibit the aggregation of Aβ_16–22; in addition, they offer molecular insight into the inhibition mechanism, thus providing new clues for the design of therapeutic drugs against amyloidosis.     

Potential Prevention and Treatment of Maifanite for Alzheimer's Disease Based on Behavior Test, Oxidative Stress Assay, and Trace Element Analysis in Hippocampus of Aβ(25–35)-Induced AD Rats

This study aimed to assess whether maifanite can improve the learning and memory, and antioxidant abilities of Alzheimer’s disease (AD) rats. The 70 rats were divided into seven groups: [A] normal control group, [B] AD model group, [C] sham group, [D] positive control group (donepezil), [E] low-dose maifanite group, [F] middle-dose maifanite group, [G] high-dose maifanite group. For [B], [D], [E], [F], and [G] groups, Aβ_(25–35) ventricle injection was carried out, then respective medicine were administered once a day for 60 consecutive days. The step-down and step-through test were used to measure learning and memory ability. The hippocampus levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were assayed. The hippocampus contents of Al, Fe, Cu, Zn, Se, and Mn were analyzed by inductively coupled plasma–atomic emission spectrometer. Maifanite decreased the acquisition errors and the retention errors while prolonging the step-down latency, and decreased the number of electric shocks while prolonging the first latency of AD rats. Aβ_(25–35) ventricle injection initiated the decrease of SOD and GSH-Px activities and the increase of MDA content, and triggered the rise of Al, Fe, and Cu levels and the decline of Mn, Zn, and Se levels. The SOD and GSH-Px activities were enhanced followed by reduced MDA level, and the levels of Mn, Zn, and Se increased accompanied by Al, Fe, and Cu decreased in the maifanite treat groups. Maifanite could improve the learning and memory, and the antioxidant abilities of AD rats. Maifanite had the potential prevention and treatment for AD.