Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Am J Trop Med Hyg ; 102(2): 339-345, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31802738

RESUMO

Infection with Strongyloides stercoralis can cause life-threatening disease in immunocompromised patients. Strongyloidiasis is thought to be hyper-endemic in tropical Australia, but there are limited contemporary seroprevalence data to inform local elimination strategies. To define the temporospatial epidemiology of strongyloidiasis in Far North Queensland, tropical Australia, the serology results of 2,429 individuals tested for the infection between 2000 and 2018 were examined. The proportion of positive tests fell from 36/69 (52.2%) in 2000 to 18/222 (8.1%) in 2018 (P < 0.001). Indigenous patients were more likely to have a positive result (Odds Ratio [OR]: 3.9, 95% CI: 3.0-5.0); however, by the end of the study period, residence in a rural or remote location (OR 3.9 (95% CI: 1.2-13.0), P = 0.03) was a more important risk factor for seropositivity than Indigenous status (OR 1.1 (95% CI: 0.4-3.1) P = 0.91). Ivermectin prescription data were available for the period 2004-2018, with annual prescriptions increasing from 100 to 185 boxes (P = 0.01). The volume of ivermectin dispensed correlated negatively with seropositivity (Spearman's rho = -0.62, P = 0.02). An expanded environmental health program was implemented during the study period and likely contributed to the declining seroprevalence; however, the relative contributions of the individual components of this program are difficult to quantify. The seroprevalence of strongyloidiasis has declined markedly in this region of tropical Australia despite there being no targeted campaign to address the disease. Expanded prescription of ivermectin and public health interventions targeting the few remaining high-prevalence communities would be expected to expedite disease elimination.


Assuntos
Ivermectina/uso terapêutico , Strongyloides stercoralis/imunologia , Estrongiloidíase/tratamento farmacológico , Estrongiloidíase/epidemiologia , Animais , Anticorpos Anti-Helmínticos/sangue , Humanos , Prevalência , Queensland/epidemiologia , Estudos Retrospectivos , População Rural , Estudos Soroepidemiológicos
2.
Mon Not R Astron Soc ; 481(2): 2371-2383, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30319155

RESUMO

Low-redshift measurements of baryon acoustic oscillations (BAO) measure the late-time evolution of the Universe and are a vital probe of dark energy. Over the past decade both the 6-degree Field Galaxy Survey (6dFGS) and Sloan Digital Sky Survey Main Galaxy Sample (SDSS MGS) have provided important distance constraints at [Formula: see text] < 0.3. In this paper we re-evaluate the cosmological information from the BAO detection in 6dFGS making use of halo occupation distribution (HOD)-populated COmoving Lagrangian Acceleration (COLA) mocks for an accurate covariance matrix and take advantage of the now commonly implemented technique of density field reconstruction. For the 6dFGS data, we find consistency with the previous analysis, and obtain an isotropic volume-averaged distance measurement of [Formula: see text] but with a highly non-Gaussian likelihood. We combine our measurement from both the post-reconstruction clustering of 6dFGS and SDSS MGS offering an updated constraint in this redshift regime, [Formula: see text]. This measurement tightens the constraint in comparison to the result from SDSS MGS alone, especially at the 2σ and higher significance levels. These measurements are consistent with standard Λcold dark matter (ΛCDM) and after fixing the standard ruler using a Planck prior on Ω m h 2, the joint analysis gives [Formula: see text]. This result is consistent with other BAO and Cosmic microwave background (CMB) studies but is in >2σ tension with supernova distance ladder measurements. In the near future both the Taipan Galaxy Survey and the Dark Energy Spectroscopic Instrument (DESI) will improve this measurement to [Formula: see text] at low redshift.

3.
Med Phys ; 34(4): 1496-505, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17500480

RESUMO

We investigated the utility of three manual planimetric methods to quantify carotid plaque volume. A single observer measured 15 individual plaques from 15 three-dimensional (3D) ultrasound (3D US) images of patients ten times each using three different planimetric approaches. Individual plaque volumes were measured (range: 32.6-597.1 mm3) using a standard planimetric approach (M1) whereby a plaque end was identified and sequential contours were measured. The same plaques were measured using a second approach (M2), whereby plaque ends were first identified and the 3D US image of the plaque was then subdivided into equal intervals. A third method (M3) was used to measure total plaque burden (range: 165.1-1080.0 mm3) in a region (+/- 1.5 cm) relative to the carotid bifurcation. M1 systematically underestimated individual plaque volume compared to M2 (V2 = V1 + 14.0 mm3, r = 0.99, p = 0.006) due to a difference in the mean plaque length measured. Coefficients of variance (CV) for M1 and M2 decrease with increasing plaque volume, with M2 results less than M1. Root mean square difference between experimental and theoretical CV for M2 was 3.2%. The standard deviation in the identification of the transverse location of the carotid bifurcation was 0.56 mm. CVs for plaque burden measured using M3 ranged from 1.2% to 7.6% and were less than CVs determined for individual plaque volumes of the same volume. The utility of M3 was demonstrated by measuring carotid plaque burden and volume change over a period of 3 months in three patients. In conclusion, M2 was determined to be a more superior measurement technique than M1 to measure individual plaque volume. Furthermore, we demonstrated the utility of M3 to quantify regional plaque burden and to quantify change in plaque volume.


Assuntos
Algoritmos , Anatomia Transversal/métodos , Estenose das Carótidas/diagnóstico por imagem , Ecocardiografia Tridimensional/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Idoso , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Mon Not R Astron Soc ; 464(4): 4807-4822, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28066154

RESUMO

We present results from the 2D anisotropic baryon acoustic oscillation (BAO) signal present in the final data set from the WiggleZ Dark Energy Survey. We analyse the WiggleZ data in two ways: first using the full shape of the 2D correlation function and secondly focusing only on the position of the BAO peak in the reconstructed data set. When fitting for the full shape of the 2D correlation function we use a multipole expansion to compare with theory. When we use the reconstructed data we marginalize over the shape and just measure the position of the BAO peak, analysing the data in wedges separating the signal along the line of sight from that parallel to the line of sight. We verify our method with mock data and find the results to be free of bias or systematic offsets. We also redo the pre-reconstruction angle-averaged (1D) WiggleZ BAO analysis with an improved covariance and present an updated result. The final results are presented in the form of Ω c h2, H(z), and DA (z) for three redshift bins with effective redshifts z = 0.44, 0.60, and 0.73. Within these bins and methodologies, we recover constraints between 5 and 22 per cent error. Our cosmological constraints are consistent with flat ΛCDM cosmology and agree with results from the Baryon Oscillation Spectroscopic Survey.

5.
Acta Crystallogr B ; 63(Pt 3): 396-401, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17507752

RESUMO

The structure of a new mineral jadarite, LiNaSiB(3)O(7)(OH) (IMA mineral 2006-36), has been determined by simulated annealing and Rietveld refinement of laboratory X-ray powder diffraction data. The structure contains a layer of corner-sharing, tetrahedrally coordinated Li, Si and B forming an unbranched vierer single layer, which is decorated with triangular BO(3) groups. The Na ion is situated between the tetrahedral layers in a distorted octahedral site. As the very high boron content in this mineral makes obtaining neutron diffraction data very problematic, ab initio optimization using VASP was used to validate the structure and to better localize the H atom. The H atom is located on the apex of the triangular BO(3) group and is involved in a weak intralayer hydrogen bond. The final Rietveld refinement agrees with the ab initio optimization with regard to a hydrogen bond between the H atom and one of the tetrahedral corner O atoms. The refined structure seems to be of a remarkably high quality given the complexity of the structure, the high proportion of very light elements and the fact that it was determined from relatively low-resolution laboratory data over a limited 2theta range (10-90 degrees 2theta).

6.
Nature ; 416(6877): 150-2, 2002 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-11894086

RESUMO

The motion of our Galaxy through the Universe is reflected in a systematic shift in the temperature of the cosmic microwave background-because of the Doppler effect, the temperature of the background is about 0.1 per cent higher in the direction of motion, with a correspondingly lower temperature in the opposite direction. This effect is known as dipole anisotropy. If our standard cosmological model is correct, a related dipole effect should also be present as an enhancement in the surface density of distant galaxies in the direction of motion. The main obstacle to finding this signal is the uneven distribution of galaxies in the local supercluster, which drowns out the small cosmological signal. Here we report a detection of the expected cosmological dipole anisotropy in the distribution of galaxies. We use a survey of radio galaxies that are mainly located at cosmological distances, so the contamination from nearby clusters is small. When local radio galaxies are removed from the sample, the resulting dipole is in the same direction as the temperature anisotropy of the microwave background, and close to the expected amplitude. The result therefore confirms the standard cosmological interpretation of the microwave background.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA