3,667 research outputs found
Midlife risk factor exposure and incidence of cardiac arrest depending on cardiac or non-cardiac origin
Objective: Little is known about midlife risk factors of future cardiac arrest. Our objective was to evaluate cardiovascular risk factors in midlife in relation to the risk of cardiac arrest (CA) of cardiac and non-cardiac origin later in life. Methods: We cross-matched individuals of the population based MalmĂś Diet and Cancer study (n = 30,447) with the local CA registry of the city of MalmĂś. Baseline exposures were related to incident CA. Results: During a mean follow-up of 17.6. Âą. 4.6. years, 378 CA occurred, of whom 17.2% survived to discharge. Independent midlife risk factors for CA of cardiac origin included coronary artery disease (HR 2.84 (1.86-4.34) (p 30kg/m2) (HR 2.37 (1.51-3.71) (p <0.001)), smoking (HR 2.05 (1.33-3.15) (p <0.001)) and being on antihypertensive treatment (HR 2.25 (1.46-3.46) (p <0.001)). Conclusion: Apart from smoking, which increases the risk of CA in general, the midlife risk factor pattern differs between CA of cardiac and non-cardiac origin. Whereas CA of cardiac origin is predicted by history of cardiovascular disease, dyslipidemia and diabetes mellitus, the main risk factors for CA of non-cardiac origin are obesity and hypertension. In addition to control of classical cardiovascular risk factors for prevention of CA, our results suggest that prevention of midlife obesity may reduce the risk of CA of non-cardiac origin
Guiding explanation construction by children at the entry points of learning progressions
Policy documents in science education suggest that even at the earliest years of formal schooling, students are capable of constructing scientific explanations about focal content. Nonetheless, few research studies provide insights into how to effectively provide scaffolds appropriate for late elementaryâage students' fruitful creation of scientific explanations. This article describes two research studies to address the question, what makes explanation construction difficult for elementary students? The studies were conducted in urban fourth, fifth, and sixth grade classrooms where students were learning science through curricular units that contained 8 weeks of scaffoldârich activities focused on explanation construction. The first study focused on the kind and amount of information scaffoldârich assessments provided about young students' abilities to construct explanations under a range of scaffold conditions. Results demonstrated that fifth and sixth grade tests provided strong information about a range of students' abilities to construct explanations under a range of supported conditions. On balance, the fourth grade test did not provide as much information, nor was this test curricularâsensitive. The second study provided information on preâpost test achievement relative to the amount of curricular intervention utilized over the 8âweek time period with each cohort. Results demonstrated that when taking the amount of the intervention into account, there were strong learning gains in all three gradeâlevel cohorts. In conjunction with the preâpost study, a typeâofâerror analysis was conducted to better understand the nature of errors among younger students. This analysis revealed that our youngest students generated the most incomplete responses and struggled in particular ways with generating valid evidence. Conclusions emphasize the synergistic value of research studies on scaffoldârich assessments, curricular scaffolds, and teacher guidance toward a more complete understanding of how to support young students' explanation construction. Š 2011 Wiley Periodicals, Inc. J Res Sci Teach 49: 141â165, 2012Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90320/1/20454_ftp.pd
Nail abnormalities identified in an ageing study of 30 inbred mouse strains.
In a large-scale ageing study, 30 inbred mouse strains were systematically screened for histologic evidence of lesions in all organ systems. Ten strains were diagnosed with similar nail abnormalities. The highest frequency was noted in NON/ShiLtJ mice. Lesions identified fell into two main categories: acute to chronic penetration of the third phalangeal bone through the hyponychium with associated inflammation and bone remodelling or metaplasia of the nail matrix and nail bed associated with severe orthokeratotic hyperkeratosis replacing the nail plate. Penetration of the distal phalanx through the hyponychium appeared to be the initiating feature resulting in nail abnormalities. The accompanying acute to subacute inflammatory response was associated with osteolysis of the distal phalanx. Evaluation of young NON/ShiLtJ mice revealed that these lesions were not often found, or affected only one digit. The only other nail unit abnormality identified was sporadic subungual epidermoid inclusion cysts which closely resembled similar lesions in human patients. These abnormalities, being age-related developments, may have contributed to weight loss due to impacts upon feeding and should be a consideration for future research due to the potential to interact with other experimental factors in ageing studies using the affected strains of mice.American Hair Research Society Mentorship Grants (to SL and AM)
Ellison Medical Foundation (to JPS)
National Institutes of Health (AG025707, for the Shock Aging Center). The Jackson Laboratory Shared Scientific Services were supported in part by a Basic Cancer Center Core Grant from the National Cancer Institute (CA034196)
Two species of Hoploscaphites.
72 pages : illustrations (some color), map ; 26 cm.Two species of scaphitid ammonites (Ammonoidea: Ancyloceratina) from the Upper Cretaceous (lower Maastrichtian) of the Western Interior of North America are described. Hoploscaphites macer, n. sp., is medium size, with coarse ribs on the phragmocone, which become finer on the body chamber, and closely spaced ventrolateral tubercles. It occurs in the upper part of the Baculites baculus Zone and lower part of the overlying B. grandis Zone in the Pierre Shale in Montana, Wyoming, and Colorado, and in the Bearpaw Shale in Montana. Hoploscaphites criptonodosus (Riccardi, 1983) is larger and more coarsely ornamented, including one or two rows of lateral tubercles on the flanks of the phragmocone. It occurs in the upper part of the Baculites baculus Zone and overlying B. grandis Zone in the Pierre Shale in Montana, Wyoming, Colorado, and possibly South Dakota, and in the Bearpaw Shale in Montana and Saskatchewan, Canada. Both species form part of an evolving lineage of Hoploscaphites that first appears in the Western Interior of North America in the middle Campanian
Increased p53 mutation load in nontumorous human liver of Wilson disease and hemochromatosis: Oxyradical overload diseases
An investigation of the structural requirements for ATP hydrolysis and DNA cleavage by the EcoKI Type I DNA restriction and modification enzyme
Type I DNA restriction and modification enzym
Analysis of Campylobacter jejuni infection in the gnotobiotic piglet and genome-wide identification of bacterial factors required for infection
To investigate how Campylobacter jejuni causes the clinical symptoms of diarrhoeal disease in humans, use of a relevant animal model is essential. Such a model should mimic the human disease closely in terms of host physiology, incubation period before onset of disease, clinical signs and a comparable outcome of disease. In this study, we used a gnotobiotic piglet model to study determinants of pathogenicity of C. jejuni. In this model, C. jejuni successfully established infection and piglets developed an increased temperature with watery diarrhoea, which was caused by a leaky epithelium and reduced bile re-absorption in the intestines. Further, we assessed the C. jejuni genes required for infection of the porcine gastrointestinal tract utilising a transposon (Tn) mutant library screen. A total of 123 genes of which Tn mutants showed attenuated piglet infection were identified. Our screen highlighted a crucial role for motility and chemotaxis, as well as central metabolism. In addition, Tn mutants of 14 genes displayed enhanced piglet infection. This study gives a unique insight into the mechanisms of C. jejuni disease in terms of host physiology and contributing bacterial factors.This work was funded by BBSRC awards BB/F020988/1 and BB/K004514/1. Moredun Research Institute receives funding via Rural and Environment Science and Analytical Services (RESAS) division of the Scottish Government. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
The performance of muon reconstruction, identification, and triggering in CMS
has been studied using 40 inverse picobarns of data collected in pp collisions
at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection
criteria covering a wide range of physics analysis needs have been examined.
For all considered selections, the efficiency to reconstruct and identify a
muon with a transverse momentum pT larger than a few GeV is above 95% over the
whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4,
while the probability to misidentify a hadron as a muon is well below 1%. The
efficiency to trigger on single muons with pT above a few GeV is higher than
90% over the full eta range, and typically substantially better. The overall
momentum scale is measured to a precision of 0.2% with muons from Z decays. The
transverse momentum resolution varies from 1% to 6% depending on pseudorapidity
for muons with pT below 100 GeV and, using cosmic rays, it is shown to be
better than 10% in the central region up to pT = 1 TeV. Observed distributions
of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO
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