378 research outputs found
Review of indigenous knowledge in Uganda: Implications for its promotion
Indigenous knowledge (IK) has a role to play for households and community well-being in Uganda. However, IK is undergoing significant change and is on the decline in Uganda because of factors such as acculturation or the loss of IK through exposure to external cultures. In this paper we review some of the roles of, and threats to, IK with particular reference to the local community of Kaliro District. We make some recommendations on how to conserve IK in Kaliro and elsewhere in Uganda
Saxion Emission from SN1987A
We study the possibility of emission of the saxion, a superpartner of the
axion, from SN1987A. The fact that the observed neutrino pulse from SN1987A is
in excellent agreement with the current theory of supernovae places a strong
bound on the energy loss into any non-standard model channel, therefore
enabling bounds to be placed on the decay constant, f_a, of a light saxion. The
low-energy coupling of the saxion, which couples at high energies to the QCD
gauge field strength, is expected to be enhanced from QCD scaling, making it
interesting to investigate if the saxion could place stronger bounds on f_a
than the axion itself. Moreover, since the properties of the saxion are
determined by f_a, a constraint on this parameter can be translated into a
constraint on the supersymmetry breaking scale. We find that the bound on f_a
from saxion emission is comparable with the one derived from axion emission due
to a cancellation of leading-order terms in the soft-radiation expansion.Comment: 18 pages, 2 figures; minor changes, typos corrected, version to
appear in JHE
Cardiac catheterization under echocardiographic control in a pregnant woman
A 22 year old woman had signs of rheumatic mitral and aortic valve disease early in pregnancy. Cardiac catheterization was performed during her third month of pregnancy under two-dimensional echocardiographic control without the use of ionizing radiation. Severe mitral stenosis with mild aortic stenosis was found. Five cubic centimeters of 5 percent dextrose in water were injected by hand to obtain left ventriculograms and supravalvular aortograms of sufficient quality to diagnose valvular regurgitation. The use of "echo-catheterization" may have significant advantages in selected clinical situations
Videodensitometric processing of contrast two-dimensional echocardiographic data
We developed a computer program to analyze videodensity changes due to contrast appearance within a given operator-designated rectangle using two-dimensional echocardiograms previously recorded on videotape. Videodensity curves have been obtained from two-dimensional echocardiographic recordings in 14 patients after a total of 32 injections of 5% dextrose solution into the left ventricle during cardiac catheterization. The resulting videodensity vs time curves have some characteristics of indicator-dilution curves. The decay phase of these curves is largely mono-exponential. Potential clinical applications of this technique in measurement of ejection fraction, cardiac output and shunt quantification are discussed, as well as some potential limitations
Restenosis, reocclusion and adverse cardiovascular events after successful balloon angioplasty of occluded versus nonoccluded coronary arteries: Results from the multicenter american research trial with cilazapril after angioplasty to prevent transluminal coronary obstruction and restenosis (MARCATOR)
OBJECTIVES: This study sought to compare the frequency of restenosis, reocclusion and adverse cardiovascular events after angioplasty of occluded versus nonoccluded coronary arteries.
BACKGROUND: Angioplasty of chronically occluded coronary arteries is believed to be associated with a higher frequency of restenosis and reocclusion than angioplasty of subtotal stenoses. Whether this leads to adverse cardiovascular events is unknown.
METHODS: The Multicenter American Research Trial With Cilazapril After Angioplasty to Prevent Restenosis (MARCATOR) was a placebo-controlled trial with angiographic follow-up to determine the effect of the angiotensin-converting enzyme inhibitor cilazapril on the frequency of restenosis. In this trial, restenosis was defined as 1) angiographic reduction of minimal lumen diameter > or = 0.72 mm between angioplasty and the follow-up visit; and 2) > 50% diameter stenosis on the follow-up angiogram. We identified
Big Corrections from a Little Higgs
We calculate the tree-level expressions for the electroweak precision
observables in the SU(5)/SO(5) littlest Higgs model. The source for these
corrections are the exchange of heavy gauge bosons, explicit corrections due to
non-linear sigma-model dynamics and a triplet Higgs VEV. Weak isospin violating
contributions are present because there is no custodial SU(2) global symmetry.
The bulk of these weak isospin violating corrections arise from heavy gauge
boson exchange while a smaller contribution comes from the triplet Higgs VEV. A
global fit is performed to the experimental data and we find that throughout
the parameter space the symmetry breaking scale is bounded by f > 4 TeV at 95%
C.L. Stronger bounds on f are found for generic choices of the high energy
gauge couplings. We find that even in the best case scenario one would need
fine tuning of less than a percent to get a Higgs mass as light as 200 GeV.Comment: 20 pages, 5 figures included, typos fixed, comments on the effects of
extra vector-like heavy fermions adde
Direct stenting with the Bx VELOCITY balloon-expandable stent mounted on the Raptor rapid exchange delivery system versus predilatation in a European randomized Trial: the VELVET trial.
Abstract
AIMS: This study examined the six-month angiographic results of direct coronary stenting, and compared the nine-month safety, efficacy and cost of this strategy versus stenting after balloon predilatation.
METHODS: In phase I of VELVET, 122 patients (mean age = 62.3 +/- 10.1 years, 77% male, 11% with diabetes) with angina pectoris or myocardial ischemia resulting from a single de novo 51% to 95% coronary stenosis underwent direct stenting. The endpoints of phase I included angiographic findings and rates of major adverse cardiac events up to six months of follow-up. In phase II, 401 patients (mean age = 61.3 +/- 10.8 years, 79% male, 16% with diabetes) with angina pectoris or documented myocardial ischemia resulting from single or multiple, de novo or restenotic, coronary lesions were randomized between direc
Non-Random mtDNA Segregation Patterns Indicate a Metastable Heteroplasmic Segregation Unit in m.3243A>G Cybrid Cells
Many pathogenic mitochondrial DNA mutations are heteroplasmic, with a mixture of mutated and wild-type mtDNA present within individual cells. The severity and extent of the clinical phenotype is largely due to the distribution of mutated molecules between cells in different tissues, but mechanisms underpinning segregation are not fully understood. To facilitate mtDNA segregation studies we developed assays that measure m.3243A>G point mutation loads directly in hundreds of individual cells to determine the mechanisms of segregation over time. In the first study of this size, we observed a number of discrete shifts in cellular heteroplasmy between periods of stable heteroplasmy. The observed patterns could not be parsimoniously explained by random mitotic drift of individual mtDNAs. Instead, a genetically metastable, heteroplasmic mtDNA segregation unit provides the likely explanation, where stable heteroplasmy is maintained through the faithful replication of segregating units with a fixed wild-type/m.3243A>G mutant ratio, and shifts occur through the temporary disruption and re-organization of the segregation units. While the nature of the physical equivalent of the segregation unit remains uncertain, the factors regulating its organization are of major importance for the pathogenesis of mtDNA diseases
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