Addressing School Dropout in Texas: A Summary for Administrators and Policymakers of "Dropout Prevention: A Practice Guide"

This booklet summarizes the information from: Dropout Prevention: A Practice Guide, available on the Institute of Education Sciences web site at http://ies.ed.gov/ncee/wwc.Educatio

Ab Initio Liquid Hydrogen Muon Cooling Simulations with ELMS in ICOOL

This paper presents new theoretical results on the passage of muons through liquid hydrogen which have been confirmed in a recent experiment. These are used to demonstrate that muon bunches may be compressed by ionisation cooling more effectively than suggested by previous calculations. Muon cooling depends on the differential cross section for energy loss and scattering of muons. We have calculated this cross section for liquid H2 from first principles and atomic data, avoiding traditional assumptions. Thence, 2-D probability maps of energy loss and scattering in mm-scale thicknesses are derived by folding, and stored in a database. Large first-order correlations between energy loss and scattering are found for H2, which are absent in other simulations. This code is named ELMS, Energy Loss & Multiple Scattering. Single particle trajectories may then be tracked by Monte Carlo sampling from this database on a scale of 1 mm or less. This processor has been inserted into the cooling code ICOOL. Significant improvements in 6-D muon cooling are predicted compared with previous predictions based on GEANT. This is examined in various geometries. The large correlation effect is found to have only a small effect on cooling. The experimental scattering observed for liquid H2 in the MUSCAT experiment has recently been reported to be in good agreement with the ELMS prediction, but in poor agreement with GEANT simulation.Comment: 6 pages, 3 figure

Benefits of belonging: experimental manipulation of social inclusion to enhance psychological and physiological health parameters.

OBJECTIVE: Acute changes in social belonging are important triggers for alterations in health and well-being, yet research has emphasised the negative effects of 'exclusion' at the expense of evaluating the potentially positive effects of 'inclusion'. This study examined the impact of acute belonging on physiological and psychological outcomes. DESIGN AND MAIN OUTCOME MEASURES: A healthy population (N = 138) were randomly allocated to 'included' or 'excluded' conditions. Condition-dependent differences in pre/during-task heart rate and pre/post-task self-reports of negative/positive mood, and social self-esteem, were assessed. RESULTS: Included participants showed decreased heart rate and negative mood, and increased social self-esteem. No inclusion-related change in positive mood was shown. An increase in heart rate was observed in excluded participants though no changes in negative/positive mood or social self-esteem were shown. Shifts in social self-esteem acted as a mechanism through which inclusion/exclusion impacted upon negative and positive mood alterations. Results remained significant in presence of covariates (sex, global self-esteem, rumination and social anxiety). CONCLUSION: Findings suggest that acting to enhance belonging through 'inclusion' resulted in adaptive physiological and psychological outcomes. Neutral and potentially protective responses were observed in the immediate aftermath of 'exclusion'. Self-esteem served as one route through which these effects were transmitted

Role of Dicer Enzyme in the Regulation of Store Operated Calcium Entry (SOCE) in CD4+ T Cells

Background/Aims: Activation of T cell receptors (TCRs) in CD4+ T cells leads to a cascade of signalling reactions including increase of intracellular calcium (Ca2+) levels with subsequent Ca2+ dependent stimulation of gene expression, proliferation, cell motility and cytokine release. The increase of cytosolic Ca2+ results from intracellular Ca2+ release with subsequent activation of store-operated Ca2+ entry (SOCE). Previous studies suggested miRNAs are required for the development and functions of CD4+ T cells. An enzyme called Dicer is required during the process of manufacturing mature miRNAs from the precursor miRNAs. In this study, we explored whether loss of Dicer in CD4+ T cells affects SOCE and thus Ca2+ dependent regulation of cellular functions. Methods: We tested the expression of Orai1 by q-RT-PCR and flow cytometry. Further, we measured SOCE by an inverted phase-contrast microscope with the Incident-light fluorescence illumination system using Fura-2. Intracellular Ca2+ was also measured by flow cytometry using Ca2+ sensitive dye Fluo-4. Results: We found that in Dicer deficient (DicerΔ/Δ) mice Orai1 was downregulated at mRNA and protein level in CD4+ T cells. Further, SOCE was significantly smaller in DicerΔ/Δ CD4+ T cells than in CD4+ T cells isolated from wild-type (Dicerfl/fl) mice. Conclusion: Our data suggest that miRNAs are required for adequate Ca2+ entry into CD4+ T cells and thus triggering of Ca2+ sensitive immune functions

The Remains of the Fray: Nascent Colonialism and Heterogeneous Hybridity

Investigations at the Native American site complex of Stark Farms in Mississippi, USA, have yielded numerous examples of metal artifacts of European origin. Our study suggests that they derive from contact between the AD 1540–1541 winter encampment of the Spanish Hernando de Soto expedition and the local Indigenous polity. The artifacts display a wide range of modifications, uses, and depositional contexts congruent with hybrid practices. We argue that the early colonial setting of Stark Farms requires a different perspective on cultural mixing than is often applied in studies of European colonialism. This is highlighted by the strongly improvisational nature of the modification of the metal objects, embodying a political climate in which European incursions were precarious and in which hybridity and power were heterogeneous and fluid

Structured evaluation of virtual environments for special-needs education

This paper describes the development of a structured approach to evaluate experiential and communication virtual learning environments (VLEs) designed specifically for use in the education of children with severe learning difficulties at the Shepherd special needs school in Nottingham, UK. Constructivist learning theory was used as a basis for the production of an evaluation framework, used to evaluate the design of three VLEs and how they were used by students with respect to this learning theory. From an observational field study of student-teacher pairs using the VLEs, 18 behaviour categories were identified as relevant to five of the seven constructivist principles defined by Jonassen (1994). Analysis of student-teacher behaviour was used to provide support for, or against, the constructivist principles. The results show that the three VLEs meet the constructivist principles in very different ways and recommendations for design modifications are put forward

Immersive virtual reality enables technical skill acquisition for scrub nurses in complex revision total knee arthroplasty.

INTRODUCTION: Immersive Virtual Reality (iVR) is a novel technology which can enhance surgical training in a virtual environment without supervision. However, it is untested for the training to select, assemble and deliver instrumentation in orthopaedic surgery-typically performed by scrub nurses. This study investigates the impact of an iVR curriculum on this facet of the technically demanding revision total knee arthroplasty. MATERIALS AND METHODS: Ten scrub nurses completed training in four iVR sessions over a 4-week period. Initially, nurses completed a baseline real-world assessment, performing their role with real equipment in a simulated operation assessment. Each subsequent iVR session involved a guided mode, where the software taught participants the procedural choreography and assembly of instrumentation in a simulated operating room. In the latter three sessions, nurses also undertook an assessment in iVR. Outcome measures were related to procedural sequence, duration of surgery and efficiency of movement. Transfer of skills from iVR to the real world was assessed in a post-training simulated operation assessment. A pre- and post-training questionnaire assessed the participants knowledge, confidence and anxiety. RESULTS: Operative time reduced by an average of 47% across the 3 unguided sessions (mean 55.5 ± 17.6 min to 29.3 ± 12.1 min, p > 0.001). Assistive prompts reduced by 75% (34.1 ± 16.8 to 8.6 ± 8.8, p < 0.001), dominant hand motion by 28% (881.3 ± 178.5 m to 643.3 ± 119.8 m, p < 0.001) and head motion by 36% (459.9 ± 99.7 m to 292.6 ± 85.3 m, p < 0.001). Real-world skill improved from 11% prior to iVR training to 84% correct post-training. Participants reported increased confidence and reduced anxiety in scrubbing for rTKA procedures (p < 0.001). CONCLUSIONS: For scrub nurses, unfamiliarity with complex surgical procedures or equipment is common. Immersive VR training improved their understanding, technical skills and efficiency. These iVR-learnt skills transferred into the real world

Impact of deforestation on solid and dissolved organic matter characteristics of tropical peat forests: implications for carbon release

This study compares the organic chemistry of peat beneath one of last remaining pristine tropical peat forests in Southeast Asia with a neighbouring peat dome that has been deforested, but not intentionally drained, in the Belait district of Brunei Darussalam, Borneo. We characterized the solid and dissolved organic matter collected from the two domes, through a combination of methods including elemental analysis, phenolic content and Fourier transform infrared spectroscopy (FTIR) investigation of solid peat, as well as optical characterisation (absorbance, fluorescence) of dissolved organic matter (DOM). The peat had a high content of lignin, consistent with its origin from the Shorea albida trees on the domes. Dissolved organic carbon (DOC) concentration in the pore water was significantly greater in the deforested site (79.9 ± 5.5 mg l[superscript −1]) than the pristine site (62.2 ± 2.2 mg l[superscript −1]). The dissolved organic matter was richer in nitrogen and phenolics in the deforested site. The optical properties (Fluorescence Index) indicated a modification of DOM cycling in the deforested site (enhanced decomposition of the peat and fresh litter). Comparison of the solid peat composition between the two sites also suggests effects of deforestation: sulphur, nitrogen and phenolic contents were higher in the deforested site. Taken together, these observations are consistent with peat enhanced decomposition in the deforested site, even without engineered drainage.Singapore-MIT Alliance for Research and Technology. Center for Environmental Sensing and Modelin