Clinical implications of the anisotropic analytical algorithm for IMRT treatment planning and verification

PURPOSE: To determine the implications of the use of the Anisotropic Analytical Algorithm(AAA) for the production and dosimetric verification of IMRT plans for treatments of the prostate, parotid, nasopharynx and lung. METHODS: 72 IMRT treatment plans produced using the Pencil Beam Convolution (PBC)algorithm were recalculated using the AAA and the dose distributions compared. 24 of the plans were delivered to inhomogeneous phantoms and verification measurements made using a pinpoint ionisation chamber. The agreement between the AAA and measurement was determined. RESULTS: Small differences were seen in the prostate plans, with the AAA predicting slightly lower minimum PTV doses. In the parotid plans, there were small increases in the lens and contralateral parotid doses while the nasopharyngeal plans revealed a reduction in the volume of the PTV covered by the 95% isodose (the V95%) when the AAA was used. Large changes were seen in the lung plans, the AAA predicting reductions in the minimum PTV dose and large reductions in the V95%. The AAA also predicted small increases in the mean dose to the normal lung and the V20. In the verification measurements, all AAA calculations were within 3% or 3.5mm distance to agreement of the measured doses. Conclusions: The AAA should be used in preference to the PBC algorithm for treatments involving low density tissue but this may necessitate re-evaluation of plan acceptability criteria. Improvements to the Multi-Resolution Dose Calculation algorithm used in the inverse planning are required to reduce the convergence error in the presence of lung tissue. There was excellent agreement between the AAA and verification measurements for all sites

So Many Books They Don’t Even All Fit on the Bookshelf”: An Examination of Low-income and Ethnic Minority Mothers’ Home Literacy Practices, Beliefs, and Influencing Factors

Given the need to enhance the academic language and early literacy skills of young children from low-income homes and the importance of the home literacy environment (HLE) in supporting children’s development, the purpose of this qualitative study was to better understand the HLE of low-income African-American and Latino mothers of preschool children living in the United States. Specifically, research aims were to examine HLE practices, beliefs and influential factors as well as to compare the HLE of African-American and Latino, specifically Puerto Rican, families. Semi-structured interviews were conducted with 10 African-American and 10 Puerto Rican mothers. Data were analyzed using the consensual qualitative research method. Twelve themes were identified: provision of educational materials, engagement with books, focus on print, implicit language opportunities, focus on other pre-academic skills, social interactions with books, influence of school, influence of other adults, parent reading interest/ability, child reading interest, parent commitment to child’s success, and family stressors. Few differences emerged between African-American and Puerto Rican mothers. Implications for language and literacy intervention development are discussed

Depression, Control, and Climate: An Examination of Factors Impacting Teaching Quality in Preschool Classrooms

This study investigated the relationship of preschool teachers’ self-reported depressive symptomatology, perception of classroom control, and perception of school climate to classroom quality as measured by the Classroom Assessment Scoring System (CLASS Pre-K). The sample consisted of 59 urban preschool classrooms serving low-income and linguistically diverse students in the northeastern and southeastern United States. Results of hierarchical linear modeling revealed that teachers’ individual report of depressive symptomatology was significantly and negatively predictive of their observed instructional support and classroom organization quality domains. The findings of this study have implications for increasing access to mental health supports for teachers in an effort to minimize depressive symptoms and potentially improve classroom quality

A Partnered Approach to School Change in a Rural Community: Reflections and Recommendations

With so many education policies and practices made at the local level, community-based foundations are in a unique position to support their local school districts in taking a comprehensive, systematic approach to improving the lives of young people. This article describes a research–practice partnership designed to produce school improvement in a rural community in western Virginia and reflects on a three-year collaboration among The Alleghany Foundation, two school districts, and the University of Virginia. The partners identified challenges and strengths within the school districts and the community; gathered and analyzed existing district data and new findings from interviews and surveys of stakeholders; identified problems and promising programs to address them; and developed and communicated a plan for action. Now, the schools, working with the foundation and the community, are implementing that plan. The collaboration provided clear evidence that sustained change will occur only if it aligns with the goals of school leaders and fully engages members of the community, and it sheds light on the unique challenges and strengths present in a small rural community that will influence foundation work. The process also produced five recommendations for foundations that seek a partnered approach to school change

Electrophysiology of Concatameric Pannexin 1 Channels Reveals the Stoichiometry of C-Terminal Autoinhibition

Codi d'Art Públic: 8008-1 (La República); Reportatge realitzat als dies 4 i 18-7-1990Pericas, Enric (arquitecte); Viaplana, Albert (arquitecte i estructura); Viladomat Massanas, Josep (escultura);Joan Pie (Medalló); Piñón, Helio (Estr

The language and literacy development of young dual language learners: A critical review

The number of children living in the United States who are learning two languages is increasing greatly. However, relatively little research has been conducted on the language and literacy development of dual language learners (DLLs), particularly during the early childhood years. To summarize the extant literature and guide future research, a critical analysis of the literature was conducted. A search of major databases for studies on young typically developing DLLs between 2000–2011 yielded 182 peer-reviewed articles. Findings about DLL children’s developmental trajectories in the various areas of language and literacy are presented. Much of these findings should be considered preliminary, because there were few areas where multiple studies were conducted. Conclusions were reached when sufficient evidence existed in a particular area. First, the research shows that DLLs have two separate language systems early in life. Second, differences in some areas of language development, such as vocabulary, appear to exist among DLLs depending on when they were first exposed to their second language. Third, DLLs’ language and literacy development may differ from that of monolinguals, although DLLs appear to catch up over time. Fourth, little is known about factors that influence DLLs’ development, although the amount of language exposure to and usage of DLLs’ two languages appears to play key roles. Methodological issues are addressed, and directions for future research are discussed

Factor Analysis of the Classroom Assessment Scoring System Replicates the Three Domain Structure and Reveals no Support for the Bifactor Model in German Preschools

The quality of early childhood education and care (ECEC) is important for children’s development. One instrument that was developed to assess an aspect of ECEC quality is the Classroom Assessment Scoring System for pre-kindergarten children (CLASS Pre-K). We examined the factorial validity of the instrument using data from 177 German preschool classrooms. The three-factor teaching through interaction model (Hamre et al., 2013) was contrasted to a one-factor, a two-factor, and a bifactor model as proposed by Hamre et al. (2014). Our results indicated that the three-factor structure with the domains of emotional support, classroom organization, and instructional support fit the data best. The fit of the teaching through interaction model was satisfying after adding a cross-loading of the dimension language modeling on emotional support, and two correlated residuals. Evidence of convergent and discriminant validity are provided. In terms of factor structure and pattern score comparisons, the results were similar to previous United States and German studies. The discussion concerns the justifiability of the factor model revisions and draws directions for further research. We concluded that our study offers further evidence of the applicability of the CLASS Pre-K for the assessment of teacher–child interaction quality in the German context

Pannexin 1 channels mediate ‘find-me’ signal release and membrane permeability during apoptosis

Apoptotic cells release ‘find-me’ signals at the earliest stages of death to recruit phagocytes1. The nucleotides ATP and UTP represent one class of find-me signals2, but their mechanism of release is not known. Here, we identify the plasma membrane channel pannexin 1 (PANX1) as a mediator of find-me signal/nucleotide release from apoptotic cells. Pharmacological inhibition and siRNA-mediated knockdown of PANX1 led to decreased nucleotide release and monocyte recruitment by apoptotic cells. Conversely, PANX1 over-expression enhanced nucleotide release from apoptotic cells and phagocyte recruitment. Patch-clamp recordings showed that PANX1 was basally inactive, and that induction of PANX1 currents occurred only during apoptosis. Mechanistically, PANX1 itself was a target of effector caspases (caspases 3 and 7), and a specific caspase-cleavage site within PANX1 was essential for PANX1 function during apoptosis. Expression of truncated PANX1 (at the putative caspase cleavage site) resulted in a constitutively open channel. PANX1 was also important for the ‘selective’ plasma membrane permeability of early apoptotic cells to specific dyes3. Collectively, these data identify PANX1 as a plasma membrane channel mediating the regulated release of find-me signals and selective plasma membrane permeability during apoptosis, and a new mechanism of PANX1 activation by caspases

Dosimetry tools and techniques for IMRT

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98734/1/MPH001313.pd