Phenotypic and functional analysis of positive selection in the gamma/delta T cell lineage.

Recent evidence suggests that T cells expressing gamma/delta antigen receptors (T cell receptor [TCR]) are subject to positive selection during development. We have shown that T cells expressing a class I major histocompatibility complex (MHC)-specific gamma/delta TCR transgene (tg) are not positively selected in class I MHC-deficient, beta 2-microglobulin (beta 2m) gene knockout mice (tg+ beta 2m-). In this report, we examine phenotypic and functional parameters of gamma/delta positive selection in this transgenic model system. TCR-gamma/delta tg+ thymocytes of mature surface phenotype (heat stable antigen-, CD5hi) were found in beta 2m+ but not in beta 2m- mice. Moreover, subsets of tg+ thymocytes with the phenotype of activated T cells (interleukin [IL]2R+, CD44hi, or Mel-14lo) were also present only in the beta 2m+ mice. Cyclosporine A, which blocks positive selection of TCR-alpha/beta T cells, also inhibited gamma/delta tg+ T cell development. These results support the idea that positive selection of TCR-gamma/delta requires active TCR-mediated signal transduction. Whereas tg+ beta 2m+ thymocytes produced IL-2 and proliferated when stimulated by alloantigen, TCR engagement of tg+ beta 2m- thymocytes by antigen induced IL-2R expression but was uncoupled from the signal transduction pathway leading to IL-2 production and autocrine proliferation. Overall, these results demonstrate significant parallels between gamma/delta and alpha/beta lineage development, and suggest a general role for TCR signaling in thymic maturation

Perceptions of High School Principals of the Role of Multi-Tiered Systems of Support-- Formally RTI-- In Bringing about Social Justice and Equity for Black Boys

Historically, Black males are disproportionately represented as the least likely to graduate at every level of education and the demographic most likely placed in Special Education courses, incarcerated, as victims of homicide and who live in poverty. The United States of America implemented a voluntary program, Multi-tiered Systems of Support for educators to intervene with proactive measures that target groups that systemically fail: students of color, English learners, students with disabilities and the poor. The purpose of this research is to observe the perceptions of school principals who have implemented Multi-tiered Systems of Support (MTSS) as an education program for a minimum of three years as instructional leaders for the high schools in which they run

Quantizing the electromagnetic field near two-sided semitransparent mirrors

This paper models light scattering through flat surfaces with finite transmission, reflection, and absorption rates, with wave packets approaching the mirror from both sides. While using the same notion of photons as in free space, our model also accounts for the presence of mirror images and the possible exchange of energy between the electromagnetic field and the mirror surface. To test our model, we derive the spontaneous decay rate and the level shift of an atom in front of a semitransparent mirror as a function of its transmission and reflection rates. When considering limiting cases and using standard approximations, our approach reproduces well-known results but it also paves the way for the modeling of more complex scenarios

Percentile reference values for anthropometric body composition indices in European children from the IDEFICS study

INTRODUCTION: To characterise the nutritional status in children with obesity or wasting conditions, European anthropometric reference values for body composition measures beyond the body mass index (BMI) are needed. Differentiated assessment of body composition in children has long been hampered by the lack of appropriate references. OBJECTIVES: The aim of our study is to provide percentiles for body composition indices in normal weight European children, based on the IDEFICS cohort (Identification and prevention of Dietary-and lifestyle-induced health Effects in Children and infantS). METHODS: Overall 18 745 2.0-10.9-year-old children from eight countries participated in the study. Children classified as overweight/obese or underweight according to IOTF (N = 5915) were excluded from the analysis. Anthropometric measurements (BMI (N = 12 830); triceps, subscapular, fat mass and fat mass index (N = 11 845-11 901); biceps, suprailiac skinfolds, sum of skinfolds calculated from skinfold thicknesses (N = 8129-8205), neck circumference (N = 12 241); waist circumference and waist-to-height ratio (N = 12 381)) were analysed stratified by sex and smoothed 1st, 3rd, 10th, 25th, 50th, 75th, 90th, 97th and 99th percentile curves were calculated using GAMLSS. RESULTS: Percentile values of the most important anthropometric measures related to the degree of adiposity are depicted for European girls and boys. Age-and sex-specific differences were investigated for all measures. As an example, the 50th and 99th percentile values of waist circumference ranged from 50.7-59.2 cm and from 51.3-58.7 cm in 4.5-to < 5.0-year-old girls and boys, respectively, to 60.6-74.5 cm in girls and to 59.9-76.7 cm in boys at the age of 10.5-10.9 years. CONCLUSION: The presented percentile curves may aid a differentiated assessment of total and abdominal adiposity in European children

The Response Regulator YycF Inhibits Expression of the Fatty Acid Biosynthesis Repressor FabT in Streptococcus pneumoniae

The YycFG (also known as WalRK, VicRK, MicAB, or TCS02) two-component system (TCS) is highly conserved among Gram-positive bacteria with a low G+C content. In Streptococcus pneumoniae the YycF response regulator has been reported to be essential due to its control of pcsB gene expression. Previously we showed that overexpression of yycF in S. pneumoniae TIGR4 altered the transcription of genes involved in cell wall metabolism and fatty acid biosynthesis, giving rise to anomalous cell division and increased chain length of membrane fatty acids. Here, we have overexpressed the yycFG system in TIGR4 wild-type strain and yycF in a TIGR4 mutant depleted of YycG, and analyzed their effects on expression of proteins involved in fatty acid biosynthesis during activation of the TCS. We demonstrate that transcription of the fab genes and levels of their products were only altered in the YycF overexpressing strain, indicating that the unphosphorylated form of YycF is involved in the regulation of fatty acid biosynthesis. In addition, DNA-binding assays and in vitro transcription experiments with purified YycF and the promoter region of the FabTH-acp operon support a direct inhibition of transcription of the FabT repressor by YycF, thus confirming the role of the unphosphorylated form in transcriptional regulation.This work was supported by the Spanish Ministry of Industry and Laboratorios SALVAT within the European project Eureka Σ! 3554-DEADBUGS by the Spanish Ministry of Economics and Competitiveness grants AGL2012-40084C03-01 and AGL2015-65010-C3-1-R, and by the European Union grant FP7-PEOPLE-ITN-2008-238490. The work at the CIB was performed under the auspices of the Consejo Superior de Investigaciones Científicas.S

Effectiveness of a hospital-initiated smoking cessation programme: 2-year health and healthcare outcomes

Background: Tobacco-related illnesses are leading causes of death and healthcare use. Our objective was to determine whether implementation of a hospitalinitiated smoking cessation intervention would reduce mortality and downstream healthcare usage. Methods: A 2-group effectiveness study was completed comparing patients who received the ‘Ottawa Model’ for Smoking Cessation intervention (n=726) to usual care controls (n=641). Participants were current smokers, >17 years old, and recruited during admission to 1 of 14 participating hospitals in Ontario, Canada. Baseline data were linked to healthcare administrative data. Competing-risks regression analysis was used to compare outcomes between groups. Results: The intervention group experienced significantly lower rates of all-cause readmissions, smoking-related readmissions, and all-cause emergency department (ED) visits at all time points. The largest absolute risk reductions (ARR) were observed for allcause readmissions at 30 days (13.3% vs 7.1%; ARR, 6.1% (2.9% to 9.3%); p<0.001), 1 year (38.4% vs 26.7%; ARR, 11.7% (6.7% to 16.6%); p<0.001), and 2 years (45.2% vs 33.6%; ARR, 11.6% (6.5% to 16.8%); p<0.001). The greatest reduction in risk of allcause ED visits was at 30 days (20.9% vs 16.4%; ARR, 4.5% (0.4% to 8.7%); p=0.03). Reduction in mortality was not evident at 30 days, but significant reductions were observed by year 1 (11.4% vs 5.4%; ARR 6.0% (3.1% to 9.0%); p<0.001) and year 2 (15.1% vs 7.9%; ARR, 7.3% (3.9% to 10.7%); p<0.001). Conclusions: Considering the relatively low cost, greater adoption of hospital-initiated tobacco cessation interventions should be considered to improve patient outcomes and decrease subsequent healthcare usage

The Sky is Falling: Chemical Characterization and Corrosion Evaluation of Deposition Produced During the Static Testing of Solid Rocket Motors

Static tests of horizontally restrained rocket motors at the ATK facility in Promontory UT, USA result in the deposition of entrained soil and fuel combustion products, referred to as Test Fire Soil (TFS), over areas as large as 30–50 mile2 (80–130 km2) and at distances up to 10–12 miles (16–20 km) from the test site. Chloride is the main combustion product generated from the ammonium perchlorate–aluminum based composite propellant. Deposition sampling/characterization and a 6-month field corrosivity study using mild steel coupons were conducted in conjunction with the February 25th 2010 FSM-17 static test. The TFS deposition rates at the three study sites ranged from 1 to 5 g/min/m2. TFS contained significantly more chloride than the surface soil collected from the test site. The TFS collected during two subsequent tests had similarly elevated chloride, suggesting that the results obtained in this study are applicable to other tests assuming that the rocket fuel composition remains similar. The field-deployed coupons exposed to the TFS had higher corrosion rates (3.6–5.0 mpy) than paired non-exposed coupons (1.6–1.8 mpy). Corrosion rates for all coupon

The contribution of metacognitions and attentional control to decisional procrastination

Earlier research has implicated metacognitions and attentional control in procrastination and self-regulatory failure. This study tested several hypotheses: (1) that metacognitions would be positively correlated with decisional procrastination; (2) that attentional control would be negatively correlated with decisional procrastination; (3) that metacognitions would be negatively correlated with attentional control; and (4) that metacognitions and attentional control would predict decisional procrastination when controlling for negative affect. One hundred and twenty-nine participants completed the Depression Anxiety Stress Scale 21, the Meta-Cognitions Questionnaire 30, the Attentional Control Scale, and the Decisional Procrastination Scale. Significant relationships were found between all three attentional control factors (focusing, shifting, and flexible control of thought) and two metacognitions factors (negative beliefs concerning thoughts about uncontrollability and danger, and cognitive confidence). Results also revealed that decisional procrastination was significantly associated with negative affect, all measured metacognitions factors, and all attentional control factors. In the final step of a hierarchical regression analysis only stress, cognitive confidence, and attention shifting were independent predictors of decisional procrastination. Overall these findings support the hypotheses and are consistent with the Self-Regulatory Executive Function model of psychological dysfunction. The implications of these findings are discussed