School Size, School Poverty and School-Level Mobility: Interactive Threats to School Outcomes

ABSTRACT SCHOOL SIZE, SCHOOL POVERTY AND SCHOOL-LEVEL MOBILITY: INTERACTIVE THREATS TO SCHOOL OUTCOMES by Sharon M. Thompson School-level mobility is the flow of students moving in and out of schools and has been defined as the rate of student entries and withdrawals per 100 students enrolled in a school during the year (Pike & Weisbender, 1988). Stakeholders report that school mobility disrupts the delivery, pace and effectiveness of classroom instruction, causes problems associated with classroom adjustment, and renders long-term negative effects on schools’ Adequate Yearly Progress rankings (Bruno & Isken, 1996; GAO, 2007; Kerbow, 1996; Lash & Kirkpatrick, 1990; Rhodes, 2005; Sanderson, 2003). Despite these findings very few studies have been conducted to determine the effects of mobility (particularly at the school level) and how it combines with other school-level factors such as school size and school poverty to create threats to positive school outcomes. Of the few relevant studies (e.g., Bourque, 2009; Rhodes, 2007), little attention has been given to understanding mobility’s relationships to achievement in the context of size of student enrollment, degree of poverty and longitudinal examination of achievement across multiple years. To address these gaps in the research literature, this study investigated the effects of school-level mobility on middle school reading achievement after controlling for the effects of school enrollment and poverty. Findings from regression analyses indicated significant relationships between school-level mobility and reading achievement over and beyond the relationships between school size or school-level poverty with achievement. A repeated measures procedure was used to analyze long-term effects on eighth grade reading achievement for Title I middle schools that focused on three, key variables: degree of school mobility (e.g., high versus low rate), size of student enrollment (e.g. big versus small school), test administration year(s) (e.g., 2006, 2007 and 2008) and interactions between these variables. There were significant main effects for school size, school-level mobility as well as for the year of test administration. Reading test scores rose significantly from one year to the next, big schools out-performed small schools , and highly mobile schools performed significantly lower than low mobile schools in reading achievement over a three-year period. No significant interaction effects were found. Results are discussed in terms of research and policy implications

Development of a clinical stereofield test

Several new stereoscope test cards were designed for this study to measure the maximum magnitude of the phenomenal stereofield. The magnitude of the stereofield was then compared to stereoacuity measurements. Using a Brewster stereoscope, 50 volunteer subjects viewed the test cards with each of three different instruction sets. A significant difference was found between two of the instruction sets and the size of the stereofield elicited. No correlation was found between stereoacuity and the perceived limits of the stereofield. Organization of the stereofield cannot be predicted based on geometrical models derived from measuring Panum\u27s area. The effects of temporal and spatial summation and unlimited fixation influence the size of the phenomenal stereofield. Stereoacuity alone cannot be used to predict normal from abnormal stereo-behavior

Glycemic Response to Black Beans and Chickpeas as Part of a Rice Meal: A Randomized Cross-Over Trial

Legumes, such as black beans (Phaseolus vulgaris L.) and chickpeas (Cicer arietinum L.), have a low glycemic index, and may reduce the glycemic load of meals in which they are included. Although the low glycemic response of beans consumed alone has been documented, few studies have examined the glycemic response to traditional food combinations such as black beans and rice or chickpeas and rice. This randomized cross-over study examined the glycemic and insulinemic impact of 50 grams of available carbohydrate from three test meals: plain white rice (control), black beans with rice, and chickpeas with rice among healthy adult women (n = 12, 18–65 years). Treatments were consumed on different mornings, a minimum of 7 days apart. Blood samples were collected at time 0 (fasting), and at 30, 60, 90, and 120 min postprandial, and were subsequently analyzed for glucose and insulin concentrations. Glucose response based on the incremental area under the curve showed a significant difference by treatment (p = 0.027). Changes in blood glucose concentrations were significantly different for the black bean meal and the chickpea meal in comparison to rice alone at 60 min (p = 0.026 and p = 0.024), 90 min (p = 0.001 and p = 0.012) and 120 min post prandial (p = 0.024; black bean meal). Findings indicate that combinations of black beans and chickpeas with white rice improve glycemic response, providing evidence that has promising implications for dietary guidance to reduce postprandial glucose and related health risks through traditional food pattern

Arizona Registered Dietitians Show Gaps in Knowledge of Bean Health Benefits

Registered Dietitians (RDs) promote nutrition practices and policies and can influence food consumption patterns to include nutrient dense foods such as beans. Although many evidence-based health benefits of bean consumption (e.g., cholesterol reduction, glycemic control) have been demonstrated, there is limited research on the knowledge, attitudes, and perceptions of RDs regarding the inclusion of beans in a healthy diet. To fill this existing research gap, this cross-sectional survey explored the perceptions, knowledge, and attitudes of 296 RDs in Arizona, USA, toward beans. The RDs largely held positive attitudes toward the healthfulness of beans and were aware of many health benefits. Some gaps in awareness were evident, including effect on cancer risk, intestinal health benefits, folate content, and application with celiac disease patients. RDs with greater personal bean consumption had significantly higher bean health benefit knowledge. Twenty-nine percent of the RDs did not know the meaning of ‘legume’, and over two-thirds could not define the term ‘pulse’. It is essential that RDs have up-to-date, evidence-based information regarding bean benefits to provide appropriate education to patients, clients, and the publi

The Structural Basis of Actin Organization by Vinculin and Metavinculin

Vinculin is an essential adhesion protein that links membrane-bound integrin and cadherin receptors through their intracellular binding partners to filamentous actin, facilitating mechanotransduction. Here we present an 8.5-Å-resolution cryo-electron microscopy reconstruction and pseudo-atomic model of the vinculin tail (Vt) domain bound to F-actin. Upon actin engagement, the N-terminal "strap" and helix 1 are displaced from the Vt helical bundle to mediate actin bundling. We find that an analogous conformational change also occurs in the H1' helix of the tail domain of metavinculin (MVt) upon actin binding, a muscle-specific splice isoform that suppresses actin bundling by Vt. These data support a model in which metavinculin tunes the actin bundling activity of vinculin in a tissue-specific manner, providing a mechanistic framework for understanding metavinculin mutations associated with hereditary cardiomyopathies

The effect of Vitamin D supplementation on glycaemic control in women with Gestational Diabetes Mellitus: A systematic review and meta-analysis of randomised controlled trials

Vitamin D deficiency is highly prevalent amongst pregnant women and is linked to a range of adverse complications, including gestational diabetes. However, there is no consensus among researchers regarding the impact of vitamin D supplementation in alleviating adverse effects in gestational diabetes. The objective of this systematic review and meta-analysis was to determine whether supplementation of vitamin D given to women with gestational diabetes can promote glycaemic control. EMBASE and PubMed were searched up to November, 2018. The selection criteria included randomised controlled trials of the effect of vitamin D supplementation (1000–4762 IU/day) on pregnant women with gestational diabetes mellitus. Study data and outcome measures (fasting blood glucose, glycated haemoglobin and serum insulin) were extracted from included studies. Random-effects models were used for meta-analyses. Heterogeneity tests, and analysis of the risk of bias were conducted. Most of the studies were graded as having either low risk or moderate risk of bias although two studies had a high risk of bias in the areas of blinding of participants and personnel, and incomplete outcome data. On the other hand, the heterogeneity statistic (I2) ranged from 0–41% in the studies included. Five randomised controlled trials were selected for this review and meta-analysis (involving a total of 173 participants supplemented with vitamin D and 153 participants as control drawn from the studies). Vitamin D supplementation was associated with a decrease in fasting blood glucose by a mean of 0.46 mmol/L (−0.68, −0.25) (p < 0.001), glycated haemoglobin by a mean of 0.37% (−0.65, −0.08) (p < 0.01) and serum insulin concentration by mean of 4.10 µIU/mL (−5.50, −2.71) (p < 0.001) compared to controls. This review shows evidence that vitamin D supplementation has the potential to promote glycaemic control in women with Gestational Diabetes Mellitus (GDM). However, due to the limited number of studies in the meta-analysis, the conclusion should be interpreted with caution. Further studies are needed to fully understand the exact mechanism by which vitamin D influences glucose metabolism

A Structural Model for Vinculin Insertion into PIP 2 -Containing Membranes and the Effect of Insertion on Vinculin Activation and Localization

Vinculin, a scaffolding protein that localizes to focal adhesions (FAs) and adherens junctions, links the actin cytoskeleton to the adhesive super-structure. While vinculin binds to a number of cytoskeletal proteins, it can also associate with phosphatidylinositol 4,5-bisphosphate (PIP2) to drive membrane association. To generate a structural model for PIP2-dependent interaction of vinculin with the lipid bilayer, we conducted lipid-association, nuclear magnetic resonance, and computational modeling experiments. We find that two basic patches on the vinculin tail drive membrane association: the basic collar specifically recognizes PIP2, while the basic ladder drives association with the lipid bilayer. Vinculin mutants with defects in PIP2-dependent liposome association were then expressed in vinculin knockout murine embryonic fibroblasts. Results from these analyses indicate that PIP2 binding is not required for localization of vinculin to FAs or FA strengthening, but is required for vinculin activation and turnover at FAs to promote its association with the force transduction FA nanodomain

Examination of Fluconazole-Induced Alopecia in an Animal Model and Human Cohort.

Fluconazole-induced alopecia is a significant problem for patients receiving long-term therapy. We evaluated the hair cycle changes of fluconazole in a rat model and investigated potential molecular mechanisms. Plasma and tissue levels of retinoic acid were not found to be causal. Human patients with alopecia attributed to fluconazole also underwent detailed assessment and in both our murine model and human cohort fluconazole induced telogen effluvium. Future work further examining the mechanism of fluconazole-induced alopecia should be undertaken