7,096 research outputs found
Isomorphism in expanding families of indistinguishable groups
For every odd prime and every integer there is a Heisenberg
group of order that has pairwise
nonisomorphic quotients of order . Yet, these quotients are virtually
indistinguishable. They have isomorphic character tables, every conjugacy class
of a non-central element has the same size, and every element has order at most
. They are also directly and centrally indecomposable and of the same
indecomposability type. The recognized portions of their automorphism groups
are isomorphic, represented isomorphically on their abelianizations, and of
small index in their full automorphism groups. Nevertheless, there is a
polynomial-time algorithm to test for isomorphisms between these groups.Comment: 28 page
Nano-Engineering Defect Structures on Graphene
We present a new way of nano-engineering graphene using defect domains. These
regions have ring structures that depart from the usual honeycomb lattice,
though each carbon atom still has three nearest neighbors. A set of stable
domain structures is identified using density functional theory (DFT),
including blisters, ridges, ribbons, and metacrystals. All such structures are
made solely out of carbon; the smallest encompasses just 16 atoms. Blisters,
ridges and metacrystals rise up out of the sheet, while ribbons remain flat. In
the vicinity of vacancies, the reaction barriers to formation are sufficiently
low that such defects could be synthesized through the thermally activated
restructuring of coalesced adatoms.Comment: 4 pages, 5 figure
Insect Problems that Develop on Alfalfa Following Treatment with Certain Insecticides
Author Institution: Departments of Entomology and Agronomy, Purdue University Agricultural Experiment Station, Lafayette, Indian
The Five-Question Method For Framing A Qualitative Research Study
The Five-Question Method is an approach to framing Qualitative Research, focusing on the methodologies of five of the major traditions in qualitative research: biography, ethnography, phenomenology, grounded theory, and case study. Asking Five Questions, novice researchers select a methodology appropriate to the desired perspective on the selected topic. The Method facilitates identifying and writing a Problem Statement. Through taking a future perspective, the researcher discovers the importance and direction of the study and composes a Purpose Statement. The process develops an overarching research question integrating the purpose and the research problem. The role of the researcher and management of assumptions and biases is discussed. The Five-Question Method simplifies the framing process promoting quality in qualitative research design. A course outline is appended
The Practitioner\u27s Corner: An exploration of municipal active living charter development and advocacy
Background: Numerous municipal active living-‐related charters have been adopted to promote physical activity in Canada throughout the past decade. Despite this trend, there are few published critical examinations of the process through which charters are developed and used.
Purpose: Thus, the purpose of this study was to establish greater understanding of active living charter development and advocacy.
Methods: Semi-‐structured interviews were conducted with eight primary contributors to different active living-‐related charters across Ontario, Canada. Interview questions explored participants’ experiences developing and advocating for an active living charter. Interviews were analyzed using open, axial, and selective coding.
Results and Conclusions: Participants consistently described a process whereby an impetus triggered the development of a charter, which was subsequently adopted by regional or municipal council. Continued advocacy to develop awareness of the charter and to promote desired outcomes in the community was valued and the capacity of the working group as well as the local political context played pivotal roles in determining how the charter was implemented. Outcomes were, however, only objectively evaluated in one case that was described – evaluation being a process that many participants thought was omitted in regard to their own charter. This work provides practical guidance for health professionals developing regional active living charters as a component of broader advocacy efforts
Pultrusion Die Assembly
This invention relates generally to pultrusion die assemblies, and more particularly, to a pultrusion die assembly which incorporates a plurality of functions in order to produce a continuous, thin composite fiber reinforced thermoplastic material. The invention is useful for making high performance thermoplastic composite materials in sheets which can be coiled on a spool and stored for further processing
Early Interferon-γ Production in Human Lymphocyte Subsets in Response to Nontyphoidal Salmonella Demonstrates Inherent Capacity in Innate Cells
Background
Nontyphoidal Salmonellae frequently cause life-threatening bacteremia in sub-Saharan Africa. Young children and HIV-infected adults are particularly susceptible. High case-fatality rates and increasing antibiotic resistance require new approaches to the management of this disease. Impaired cellular immunity caused by defects in the T helper 1 pathway lead to intracellular disease with Salmonella that can be countered by IFNγ administration. This report identifies the lymphocyte subsets that produce IFNγ early in Salmonella infection.
Methodology
Intracellular cytokine staining was used to identify IFNγ production in blood lymphocyte subsets of ten healthy adults with antibodies to Salmonella (as evidence of immunity to Salmonella), in response to stimulation with live and heat-killed preparations of the D23580 invasive African isolate of Salmonella Typhimurium. The absolute number of IFNγ-producing cells in innate, innate-like and adaptive lymphocyte subpopulations was determined.
Principal Findings
Early IFNγ production was found in the innate/innate-like lymphocyte subsets: γδ-T cells, NK cells and NK-like T cells. Significantly higher percentages of such cells produced IFNγ compared to adaptive αβ-T cells (Student's t test, P<0.001 and ≤0.02 for each innate subset compared, respectively, with CD4+- and CD8+-T cells). The absolute numbers of IFNγ-producing cells showed similar differences. The proportion of IFNγ-producing γδ-T cells, but not other lymphocytes, was significantly higher when stimulated with live compared with heat-killed bacteria (P<0.0001).
Conclusion/Significance
Our findings indicate an inherent capacity of innate/innate-like lymphocyte subsets to produce IFNγ early in the response to Salmonella infection. This may serve to control intracellular infection and reduce the threat of extracellular spread of disease with bacteremia which becomes life-threatening in the absence of protective antibody. These innate cells may also help mitigate against the effect on IFNγ production of depletion of Salmonella-specific CD4+-T lymphocytes in HIV infection
Playing by the rules: A developmentally appropriate introduction to rugby union
The current study examined the effect of rules changes on game behaviours and opinions of under-nine rugby union players. Eighty-nine games were filmed in five counties in England; two governed by the then current rules and three governed by new pilot rules. The pilot rules were designed to create a less structured game; reducing numbers on the pitch and limiting set pieces and specialised skills. Games played under the pilot rules had 25% more ball-in-play time; 55% more runs with the ball; more than twice as many successful passes; and nearly twice as many tries scored (ps<.001). 272 players participated in a survey. Irrespective of the rules, players identified that passing, running and tackling were key activities, while having fun and playing with friends were their main reasons for playing rugby. The results suggest that the pilot rules create a competitive game that closely matches child-led informal activities.This research was funded by a CASE studentship from the ESRC’s Capacity Building Cluster in Sport, Leisure and Tourism, based at the University of Exeter (RES-187-24-0002), in partnership with the Rugby Football Union. The authors would like to thank all the clubs and players who took part in this research and to Gary Townsend (RFU) for facilitating the process. We would also like to thank Kris James for his assistance in performance analysis of matches
A Spectroscopic Survey of the Fields of 28 Strong Gravitational Lenses: The Group Catalog
With a large, unique spectroscopic survey in the fields of 28 galaxy-scale
strong gravitational lenses, we identify groups of galaxies in the 26
adequately-sampled fields. Using a group finding algorithm, we find 210 groups
with at least five member galaxies; the median number of members is eight. Our
sample spans redshifts of 0.04 0.76 with a median of 0.31,
including 174 groups with . Groups have radial velocity
dispersions of 60 1200 km s with a median of 350
km s. We also discover a supergroup in field B0712+472 at 0.29
consisting of three main groups. We recover groups similar to 85% of
those previously reported in these fields within our redshift range of
sensitivity and find 187 new groups with at least five members. The properties
of our group catalog, specifically 1) the distribution of , 2)
the fraction of all sample galaxies that are group members, and 3) the fraction
of groups with significant substructure, are consistent with those for other
catalogs. The distribution of group virial masses agrees well with theoretical
expectations. Of the lens galaxies, 12 of 26 (46%) (B1422+231, B1600+434,
B2114+022, FBQS J0951+2635, HE0435-1223, HST J14113+5211, MG0751+2716,
MGJ1654+1346, PG 1115+080, Q ER 0047-2808, RXJ1131-1231, and WFI J2033-4723)
are members of groups with at least five galaxies, and one more (B0712+472)
belongs to an additional, visually identified group candidate. There are groups
not associated with the lens that still are likely to affect the lens model; in
six of 25 (24%) fields (excluding the supergroup), there is at least one
massive ( 500 km s) group or group candidate projected
within 2 of the lens.Comment: 87 pages, 8 figures, a version of this was published in Ap
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