Measurement of the b-jet cross-section with associated vector boson production with the ATLAS experiment at the LHC

A measurement of the cross-section for vector boson production in association with jets containing b-hadrons is presented using 35 pb-1 of data from the LHC collected by the ATLAS experiment in 2010. Such processes are not only important tests of pQCD but also large, irreducible backgrounds to searches such as a low mass Higgs boson decaying to pairs of b-quarks when the Higgs is produced in association with a vector boson. Theoretical predictions of the V+b production rate have large uncertainties and previous measurements have reported discrepancies. Cross-sections measured using in the electron and muon channels will be shown. Comparisons will be made to recent theoretical predictions at the next-to-leading order in alpha_s.Comment: Presented at the 2011 Hadron Collider Physics symposium (HCP-2011), Paris, France, November 14-18 2011, 3 pages,6 figure.

Kin discrimination in cannibalistic tadpoles of the Green Poison Frog, Dendrobates auratus (Anura, Dendrobatidae)

O consumo de indivíduos aparentados pode reduzir a aptidão inclusiva do canibal. Assim, mecanismos que permitam que um girino reconheça seus relativos e modifique seu comportamento pode reduzir os custos do canibalismo. Alternativamente, fatores ecológicos podem tornar o tratamento preferencial dos relativos custoso demais para que seja favorecido pela seleção natural. Testamos essas duas previsões no dendrobatídeo Dendrobates auratus. O efeito do parentesco sobre o canibalismo larval foi examinado por meio de uma série de tentativas de discriminação de parentes. Observamos o comportamento de girinos de grande porte diante de dois girinos menores imobilizados, um irmão e outro não-aparentado. Nesses testes de apresentação simultânea, os girinos mostraram uma preferência significativa por atacar irmãos. Em outra série de tentativas, pares de girinos de tamanhos diferentes foram colocados juntos em aquários. A maioria dos girinos de grande porte (70%) consumiu o girino menor em menos de 24 horas. O parentesco não afetou o tempo de sobrevivência do girino pequeno. Nossos resultados são consistentes com as observações de que D. auratus é um predador indiscriminado. Como os co-específicos podem ser fortes competidores, sua eliminação rápida poderia ser vantajosa, particularmente nas pequenas poças pobres em nutrientes utilizadas por essa espécie.Cannibalizing a related individual can reduce the inclusive fitness of the cannibal. Hence, mechanisms that allow a tadpole to recognize and modify its behavior toward kin may reduce the inclusive fitness costs of cannibalism. Alternatively, ecological factors may cause preferential treatment of kin to be too costly to be favored by selection. We tested these two predictions in the Green Poison Frog, Dendrobates auratus. The effect of kinship on larval cannibalism was examined through a series of kin-discrimination trials. The behavior of large tadpoles was observed when presented with two small, tethered tadpoles, one a clutchmate and one an unrelated tadpole. In these simultaneous presentation tests, tadpoles displayed a significant preference for attacking kin. In a series of timed trials, pairs of unequally sized tadpoles were placed together in containers. The majority (70%) of large tadpoles took less than 24 hr to consume the small tadpole. Kinship did not affect the survival time of the small tadpole. Our results are consistent with observations that D. auratus is an indiscriminate predator. As conspecifics may be serious competitors, their swift elimination would be an advantage, particularly in the small, nutrient-poor pools used by this species

Reading Recovery: An Evaluation of the Four-Year i3 Scale-Up

CPRE released its evaluation of one of the most ambitious and well-documented expansions of a U.S. instructional curriculum. The rigorous independent evaluation of the Investing in Innovation (i3) scale-up of Reading Recovery, a literacy intervention for struggling first graders, was a collaboration between CPRE and the Center for Research on Education and Social Policy (CRESP) at the University of Delaware. The CPRE/CRESP evaluation revealed that students who participated in Reading Recovery significantly outperformed students in the control group on measures of overall reading, reading comprehension, and decoding. These effects were similarly large for English language learners and students attending rural schools, which were the student subgroups of priority interest for the i3 scale-up grant program. The study included an in-depth analysis of program implementation. Key findings focus on the contextual factors of the school and teachers that support the program’s success and the components of instructional strength in Reading Recovery

Scientific justification for the participation of children and adolescents in HIV-1 vaccine trials in South Africa

No Abstract

Evaluation of the i3 Scale-up of Reading Recovery | Year One Report, 2011-12

Reading Recovery (RR) is a short-term early intervention designed to help the lowest-achieving readers in first grade reach average levels of classroom performance in literacy. Students identified to receive Reading Recovery meet individually with a specially trained Reading Recovery (RR) teacher every school day for 30-minute lessons over a period of 12 to 20 weeks. The purpose of these lessons is to support rapid acceleration of each child's literacy learning. In 2010, The Ohio State University received a Scaling Up What Works grant from the U.S. Department of Education's Investing in Innovation (i3) Fund to expand the use of Reading Recovery across the country. The award was intended to fund the scale-up of Reading Recovery by training 3,675 new RR Teachers in U.S. schools, thereby expanding capacity to allow service to an additional 88,200 students.The Consortium for Policy Research in Education (CPRE) was contracted to conduct an independent evaluation of the i3 scale up of Reading Recovery over the course of five years. The evaluation includes parallel rigorous experimental and quasi-experimental designs for estimating program impacts, coupled with a large-scale mixed-methods study of program implementation under the i3 scale-up. This report presents findings through the second year of the evaluation. The primary goals of this evaluation were: a) to assess the success of the scale-up in meeting the i3 grant's expansion goals; b) to document the implementation of scale-up and fidelity to program standards; and, c) to provide experimental evidence of the impacts of Reading Recovery on student learning under this scale-up effort

Lung function in HIV-infected children and adolescents

Background The advent of antiretroviral therapy has led to the improved survival of human immunodeficiency virus (HIV)-infected children to adulthood and to HIV becoming a chronic disease in older children and adolescents. Chronic lung disease is common among HIV-infected adolescents. Lung function measurement may help to delineate the spectrum, pathophysiology and guide therapy for HIV-related chronic lung disease. Aim The aim of this study was to review the available data on the spectrum and determinants of lung function abnormalities and the impact of antiretroviral therapy on lung function in perinatally HIV-infected children and adolescents. Methods Electronic databases “PUBMED”, “African wide” and “CINAHL” via EBSCO Host, using the MeSH terms “Respiratory function” AND “HIV” OR “Acquired Immunodeficiency Syndrome” AND “Children” OR “Adolescents”, were searched for relevant articles on lung function in HIV-infected children and adolescents. The search was limited to English language articles published between January 1984 and September 2017. Results Eighteen articles were identified, which included studies from Africa, the United States of America (USA) and Italy, representing 2051 HIV-infected children and adolescents, 68% on antiretroviral therapy, aged from 50 days to 24 years. Lung function abnormalities showed HIV-infected participants had increased irreversible lower airway expiratory obstruction and reduced functional aerobic impairment on exercise, compared to HIV-uninfected participants. Mosaic attenuation, extent of bronchiectasis, history of previous pulmonary tuberculosis or previous lower respiratory tract infection and cough for more than 1 month were associated with low lung function. Pulmonary function tests in children established on antiretroviral therapy did not show aerobic impairment and had less severe airway obstruction. Conclusion There is increasing evidence that HIV-infected children and adolescents have high prevalence of lung function impairment, predominantly irreversible lower airway obstruction and reduced aerobic function

Dynamic Perturbations of the T-Cell Receptor Repertoire in Chronic HIV Infection and following Antiretroviral Therapy

HIV infection profoundly affects many parameters of the immune system and ultimately leads to AIDS, yet which factors are most important for determining resistance, pathology, and response to antiretroviral treatment - and how best to monitor them - remain unclear. We develop a quantitative high-throughput sequencing pipeline to characterize the TCR repertoires of HIV-infected individuals before and after antiretroviral therapy, working from small, unfractionated samples of peripheral blood. This reveals the TCR repertoires of HIV(+) individuals to be highly perturbed, with considerably reduced diversity as a small proportion of sequences are highly overrepresented. HIV also causes specific qualitative changes to the repertoire including an altered distribution of V gene usage, depletion of public TCR sequences, and disruption of TCR networks. Short-term antiretroviral therapy has little impact on most of the global damage to repertoire structure, but is accompanied by rapid changes in the abundance of many individual TCR sequences, decreases in abundance of the most common sequences, and decreases in the majority of HIV-associated CDR3 sequences. Thus, high-throughput repertoire sequencing of small blood samples that are easy to take, store, and process can shed light on various aspects of the T-cell immune compartment and stands to offer insights into patient stratification and immune reconstitution

Evaluation of the i3 Scale-Up of Reading Recovery | Year Two Report, 2012-13

Reading Recovery is a short-term early intervention designed to help the lowest-achieving readers in first grade reach average levels of classroom performance in literacy. Students identified to receive Reading Recovery meet individually with a specially trained Reading Recovery teacher every school day for 30-minute lessons over a period of 12 to 20 weeks. The purpose of these lessons is to support rapid acceleration of each child’s literacy learning. In 2010, The Ohio State University received a Scaling Up What Works grant from the U.S. Department of Education Investing in Innovation (i3) Fund to expand the use of Reading Recovery across the country. The award was intended to fund the training of 3,675 new Reading Recovery teachers in U.S. schools, thereby expanding service to an additional 88,200 students. The Consortium for Policy Research in Education (CPRE) was contracted to conduct an independent evaluation of the i3 scale-up of Reading Recovery over the course of five years. The evaluation includes parallel rigorous experimental and quasi-experimental designs for estimating program impacts, coupled with a large-scale mixed-methods study of program implementation. This report presents the findings of the second year of the evaluation. The primary goals of this evaluation are: a) to provide experimental evidence of the impacts of Reading Recovery on student learning under this scale-up effort ; b) to assess the success of the scale-up in meeting the i3 grant’s expansion goals; and c) to document the implementation of the scale-up and fidelity to program standards. This document is the second in a series of three reports based on our external evaluation of the Reading Recovery i3 Scale-Up. This report presents results from the impact and implementation studies conducted over the 2012-2013 school year—the third year of the scale-up effort and the second full year of the evaluation. In order to estimate the impacts of the program, a sample of first graders who had been selected to receive Reading Recovery were randomly assigned to a treatment group that received Reading Recovery immediately, or to a control group that did not receive Reading Recovery until the treatment group had exited the intervention. The reading achievement of students in this sample was assessed using a standardized assessment of reading achievement—the Iowa Tests of Basic Skills (ITBS). The data for the implementation study include extensive interviews and surveys with Reading Recovery teachers, teacher leaders, site coordinators, University Training Center directors, members of the i3 project leadership team at The Ohio State University, and principals and first-grade teachers in schools involved in the scale-up. Case studies were also conducted in nine i3 scale-up schools to observe how Reading Recovery operates in different contexts

Towards Space-like Photometric Precision from the Ground with Beam-Shaping Diffusers

We demonstrate a path to hitherto unachievable differential photometric precisions from the ground, both in the optical and near-infrared (NIR), using custom-fabricated beam-shaping diffusers produced using specialized nanofabrication techniques. Such diffusers mold the focal plane image of a star into a broad and stable top-hat shape, minimizing photometric errors due to non-uniform pixel response, atmospheric seeing effects, imperfect guiding, and telescope-induced variable aberrations seen in defocusing. This PSF reshaping significantly increases the achievable dynamic range of our observations, increasing our observing efficiency and thus better averages over scintillation. Diffusers work in both collimated and converging beams. We present diffuser-assisted optical observations demonstrating $62^{+26}_{-16}$ppm precision in 30 minute bins on a nearby bright star 16-Cygni A (V=5.95) using the ARC 3.5m telescope---within a factor of $\sim$2 of Kepler's photometric precision on the same star. We also show a transit of WASP-85-Ab (V=11.2) and TRES-3b (V=12.4), where the residuals bin down to $180^{+66}_{-41}$ppm in 30 minute bins for WASP-85-Ab---a factor of $\sim$4 of the precision achieved by the K2 mission on this target---and to 101ppm for TRES-3b. In the NIR, where diffusers may provide even more significant improvements over the current state of the art, our preliminary tests have demonstrated $137^{+64}_{-36}$ppm precision for a $K_S =10.8$ star on the 200" Hale Telescope. These photometric precisions match or surpass the expected photometric precisions of TESS for the same magnitude range. This technology is inexpensive, scalable, easily adaptable, and can have an important and immediate impact on the observations of transits and secondary eclipses of exoplanets.Comment: Accepted for publication in ApJ. 30 pages, 20 figure