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An Example of Skills Development with the Instructional Skills Workshop Online

Associations of PON1 and genetic ancestry with obesity in early childhood.

Obesity in children has become an epidemic in the U.S. and is particularly prominent in minority populations such as Mexican-Americans. In addition to physical activity and diet, genetics also plays a role in obesity etiology. A few studies in adults and adolescents suggest a link between obesity and paraoxonase 1 (PON1), a multifunctional enzyme that can metabolize organophosphate pesticides and also has antioxidant properties. We determined PON1192 genotype and arylesterase levels (ARYase, measure of PON1 enzyme quantity), to characterize the relationship between PON1 and obesity in young Mexican-American children (n = 373) living in an agricultural community in California. Since PON1 polymorphisms and obesity both vary between ethnic groups, we estimated proportional genetic ancestry using 106 ancestral informative markers (AIMs). Among children, PON1192 allele frequencies were 0.5 for both alleles, and the prevalence of obesity was high (15% and 33% at ages two and five, respectively). The average proportion of European, African, and Native American ancestry was 0.40, 0.09, and 0.51, yet there was wide inter-individual variation. We found a significantly higher odds of obesity (9.3 and 2.5- fold) in PON1192QQ children compared to PON1192RR children at ages two and five, respectively. Similar relationships were seen with BMI Z-scores at age two and waist circumference at age five. After adjusting for genetic ancestry in models of PON1 and BMI Z-score, effect estimates for PON1192 genotype changed 15% and 9% among two and five year old children, respectively, providing evidence of genetic confounding by population stratification. However even after adjustment for genetic ancestry, the trend of increased BMI Z-scores with increased number of PON1192 Q alleles remained. Our findings suggest that PON1 may play a role in obesity independent of genetic ancestry and that studies of PON1 and health outcomes, especially in admixed populations, should account for differences due to population stratification

Quantum Potential and Cosmological Singularities

We apply the de Broglie-Bohm interpretation to the Wheeler-DeWitt equation for the quantum FRW cosmological model with a minimal massless scalar field. We find that the quantum FRW cosmological model has quantum potential dominated solutions that avoid the initial and the final cosmological singularities. It is suggested that the quantum potential and the back-reaction of geometry and matter fields may change the property of the cosmological singularities of the Universe.Comment: LaTeX, 9 Pages, No Figure

Embryonic stem cell-specific signatures in cancer: insights into genomic regulatory networks and implications for medicine

Embryonic stem (ES) cells are of great interest as a model system for studying early developmental processes and because of their potential therapeutic applications in regenerative medicine. Obtaining a systematic understanding of the mechanisms that control the 'stemness' - self-renewal and pluripotency - of ES cells relies on high-throughput tools to define gene expression and regulatory networks at the genome level. Such recently developed systems biology approaches have revealed highly interconnected networks in which multiple regulatory factors act in combination. Interestingly, stem cells and cancer cells share some properties, notably self-renewal and a block in differentiation. Recently, several groups reported that expression signatures that are specific to ES cells are also found in many human cancers and in mouse cancer models, suggesting that these shared features might inform new approaches for cancer therapy. Here, we briefly summarize the key transcriptional regulators that contribute to the pluripotency of ES cells, the factors that account for the common gene expression patterns of ES and cancer cells, and the implications of these observations for future clinical applications

Deportation Worry, Cardiovascular Disease Risk Factor Trajectories, and Incident Hypertension: A Community-Based Cohort Study.

Background Worry about deportation has been associated with cardiovascular disease risk factors in cross-sectional research. No research has evaluated this association longitudinally or examined the association between deportation worry and incident cardiovascular disease outcomes. Methods and Results We used data from an ongoing community-based cohort of 572 women primarily of Mexican origin. We estimated associations between self-reported deportation worry and: (1) trajectories of blood pressure, body mass index, and waist circumference with linear mixed models, and (2) incident hypertension with Cox proportional hazards models. Nearly half (48%) of women reported "a lot," 24% reported "moderate," and 28% reported "not too much" deportation worry. Higher worry at baseline was associated with nonlinear systolic blood pressure and mean arterial pressure trajectories. For example, compared with not too much worry, a lot of worry was associated with a faster initial increase (β, interaction with linear year term: 4.10; 95% CI, 1.17-7.03) followed by a faster decrease in systolic blood pressure (β, interaction with quadratic year term: -0.80; 95% CI, -1.55 to -0.06). There was weak evidence of an association between deportation worry and diastolic blood pressure and no association with body mass index, waist circumference, or pulse pressure trajectories. Among 408 women without baseline hypertension, reporting a lot (hazard ratio, 2.17; 95% CI, 1.15-4.10) and moderate deportation worry (hazard ratio, 2.48; 95% CI, 1.17-4.30) were each associated with greater risk of incident hypertension compared with reporting not too much worry. Conclusions Deportation worry may contribute to widening disparities in some cardiovascular disease risk factors and outcomes over time

Maternal urinary bisphenol a during pregnancy and maternal and neonatal thyroid function in the CHAMACOS study.

BackgroundBisphenol A (BPA) is widely used in the manufacture of polycarbonate plastic bottles, food and beverage can linings, thermal receipts, and dental sealants. Animal and human studies suggest that BPA may disrupt thyroid function. Although thyroid hormones play a determinant role in human growth and brain development, no studies have investigated relations between BPA exposure and thyroid function in pregnant women or neonates.ObjectiveOur goal was to evaluate whether exposure to BPA during pregnancy is related to thyroid hormone levels in pregnant women and neonates.MethodsWe measured BPA concentration in urine samples collected during the first and second half of pregnancy in 476 women participating in the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) study. We also measured free thyroxine (T4), total T4, and thyroid-stimulating hormone (TSH) in women during pregnancy, and TSH in neonates.ResultsAssociations between the average of the two BPA measurements and maternal thyroid hormone levels were not statistically significant. Of the two BPA measurements, only the one taken closest in time to the TH measurement was significantly associated with a reduction in total T4 (β = -0.13 µg/dL per log2 unit; 95% CI: -0.25, 0.00). The average of the maternal BPA concentrations was associated with reduced TSH in boys (-9.9% per log2 unit; 95% CI: -15.9%, -3.5%) but not in girls. Among boys, the relation was stronger when BPA was measured in the third trimester of pregnancy and decreased with time between BPA and TH measurements.ConclusionResults suggest that exposure to BPA during pregnancy is related to reduced total T4 in pregnant women and decreased TSH in male neonates. Findings may have implications for fetal and neonatal development

Dynamics of bigeye (Thunnus obesus) and yellowfin (T. albacares) tuna in Hawaii’s pelagic fisheries: analysis of tagging data with a bulk transfer model incorporating size-specific attrition

Tag release and recapture data of bigeye (Thunnus obesus) and yellowfin tuna (T. albacares) from the Hawaii Tuna Tagging Project (HTTP) were analyzed with a bulk transfer model incorporating size-specific attrition to infer population dynamics and transfer rates between various fishery components. For both species, the transfer rate estimates from the offshore handline fishery areas to the longline fishery area were higher than the estimates of transfer from those same areas into the inshore fishery areas. Natural and fishing mortality rates were estimated over three size classes: yellowfin 20–45, 46–55, and ≥56 cm and bigeye 29–55, 56–70, and ≥71 cm. For both species, the estimates of natural mortality were highest in the smallest size class. For bigeye tuna, the estimates decreased with increasing size and for yellowfin tuna there was a slight increase in the largest size class. In the Cross Seamount fishery, the fishing mortality rate of bigeye tuna was similar for all three size classes and represented roughly 12% of the gross attrition rate (includes fishing and natural mortality and emigration rates). For yellowfin tuna, fishing mortality ranged between 7% and 30%, the highest being in the medium size class. For both species, the overall attrition rate from the entire fishery area was nearly the same. However, in the specific case of the Cross Seamount fishery, the attrition rate for yellowfin tuna was roughly twice that for bigeye. This result indicates that bigeye tuna are more resident at the Seamount than yellowfin tuna, and larger bigeye tunas tend to reside longer than smaller individuals. This may result in larger fish being more vulnerable to capture in the Seamount fishery. The relatively low level of exchange between the Sea-mount and the inshore and longline fisheries suggests that the fishing activity at the Seamount need not be of great management concern for either species. However, given that the current exploitation rates are considered moderate (10–30%), and that Seamount aggregations of yellowfin and bigeye tuna are highly vulnerable to low-cost gear types, it is recommended that further increases in fishing effort for these species be monitored at Cross Seamount

A model for principals' STEM leadership capability

In this paper we develop a model for the capabilities required by principals for effective Science, Technology, Engineering and Mathematics (STEM) leadership. The model underpinned a large national cross-sectional research and development project across Australian states in both primary and secondary schools. This model is developed via synthesis of research literature across leadership and STEM education. The model consists of five dimensions of principals' STEM capability: (1) STEM discipline-specific and integrated knowledge and practices; (2) contexts; (3) dispositions; (4) tools; and (5) critical orientation. These dimensions represent distinct, but interrelated, capacities required by principals to establish and maintain positive STEM learning cultures within schools. Elaborations have been provided, in the form of capabilities, for each of these dimensions. The model has the potential for shaping principals' STEM leadership development trajectories and structuring targeted professional learning programmes for principals, teachers and other members of the school community