10,033 research outputs found
Examination of the Circle Spline Routine
The Circle Spline routine is currently being used for generating both two and three dimensional spline curves. It was developed for use in ESCHER, a mesh generating routine written to provide a computationally simple and efficient method for building meshes along curved surfaces. Circle Spline is a parametric linear blending spline. Because many computerized machining operations involve circular shapes, the Circle Spline is well suited for both the design and manufacturing processes and shows promise as an alternative to the spline methods currently supported by the Initial Graphics Specification (IGES)
UHE neutrino searches using a Lunar target: First Results from the RESUN search
During the past decade there have been several attempts to detect cosmogenic
ultra high energy (UHE) neutrinos by searching for radio Cerenkov bursts
resulting from charged impact showers in terrestrial ice or the lunar regolith.
So far these radio searches have yielded no detections, but the inferred flux
upper limits have started to constrain physical models for UHE neutrino
generation. For searches which use the Moon as a target, we summarize the
physics of the interaction, properties of the resulting Cerenkov radio pulse,
detection statistics, effective aperture scaling laws, and derivation of upper
limits for isotropic and point source models. We report on initial results from
the RESUN search, which uses the Expanded Very Large Array configured in
multiple sub-arrays of four antennas at 1.45 GHz pointing along the lunar limb.
We detected no pulses of lunar origin during 45 observing hours. This implies
upper limits to the differential neutrino flux E^2 dN/dE < 0.003 EeV km^{-2}
s^{-1} sr^{-1} and < 0.0003 EeV km$^{-2} s^{-1} at 90% confidence level for
isotropic and sampled point sources respectively, in the neutrino energy range
10^{21.6} < E(eV) < 10^{22.6}. The isotropic flux limit is comparable to the
lowest published upper limits for lunar searches. The full RESUN search, with
an additional 200 hours observing time and an improved data acquisition scheme,
will be be an order of magnitude more sensitive in the energy range 10^{21} <
E(eV) < 10^{22} than previous lunar-target searches, and will test Z burst
models of neutrino generation.Comment: 26 pages, 14 figure
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Obesity Group Medical Visits
Background: Obesity is a major risk factor associated with multiple chronic diseases, presenting a significant global health challenge. Current evidence supports that group medical visits, an alternative format for the provision of primary care, are effective in disease management.
Purpose: The goal of this project was to examine the effectiveness of group medical visits for the management of obesity in primary care.
Methods: Individuals with a BMI greater than 30 participated in a series of six multidisciplinary group medical visits over a 12-week period. Each session included a brief individual medical visit followed by group education and discussion. Topics included; introduction and goal setting, behavior changes, nutrition, physical activity, challenges/struggles, and future goals.
Results: Data was obtained pre and post 12 week group sessions from health records and from questionnaires. Nine individuals age 52 to 76, with a variety of chronic medical conditions in addition to obesity, participated. Following with 12-week group sessions, attendees, as a group had a decrease in weight (P=.006), BMI (P=.007) and waist circumference (P=.019). Participants and providers indicated high levels of satisfaction. All participants found that they were able to make better choices about general health, identified group visits as more helpful than individual healthy life style discussions, and would participate in this type of visit again.
Conclusions: This collaborative model of care needs further evaluation with larger groups; however, the group medical visit appears to be a successful method for educating and supporting lifestyle modifications for individuals with obesity in this clinical setting
Large phenotype jumps in biomolecular evolution
By defining the phenotype of a biopolymer by its active three-dimensional
shape, and its genotype by its primary sequence, we propose a model that
predicts and characterizes the statistical distribution of a population of
biopolymers with a specific phenotype, that originated from a given genotypic
sequence by a single mutational event. Depending on the ratio g0 that
characterizes the spread of potential energies of the mutated population with
respect to temperature, three different statistical regimes have been
identified. We suggest that biopolymers found in nature are in a critical
regime with g0 in the range 1-6, corresponding to a broad, but not too broad,
phenotypic distribution resembling a truncated Levy flight. Thus the biopolymer
phenotype can be considerably modified in just a few mutations. The proposed
model is in good agreement with the experimental distribution of activities
determined for a population of single mutants of a group I ribozyme.Comment: to appear in Phys. Rev. E; 7 pages, 6 figures; longer discussion in
VII, new fig.
Struggling readers? Using theory to complicate understandings of what it means to be literate in school
Theories guide many aspects of literacy research. In this article we describe four theoretical approaches that we have used in qualitative research with students who are perceived to struggle with reading in school, including: New Literacy Studies, Disability Studies in Education, Bioecological Systems Theory, and Cultural Historical Activity Theory. We provide a brief overview of each of the theories and then explain how we have used them to gain insights about students with whom we have worked in the context of our research. Although grounded in distinct perspectives, we argue that each of the theories are lenses through which we were better able to understand the complexities of students’ struggles with reading. We further argue that the theories are united in their ability to broaden the perspectives of researchers and teachers to better account for the social, cultural, and institutional factors that shape literacy teaching and learning in schools. We conclude by questioning the use of the term “struggling reader” and highlighting the implications of our individual theoretical frames and analyses for both research and practice.Accepted manuscrip
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