4,457 research outputs found
A Principal Component Analysis approach to the Star Formation History of elliptical galaxies in Compact Groups
(Abridged) Environmental differences in the stellar populations of early-type
galaxies are explored using principal component analysis (PCA), focusing on
differences between elliptical galaxies in Hickson Compact Groups (HCGs) and in
the field. The method is model-independent and relies on variations between the
observed spectra. The projections (PC1,PC2) reveal a difference with respect to
environment, with a wider range in PC1 and PC2 in the group sample. We define a
spectral parameter (zeta=0.36PC1-PC2) which simplifies this result to a single
number: field galaxies have a very similar value of zeta, whereas HCG galaxies
span a wide range in this parameter. We obtain a strong correlation between the
values of zeta and the mass fraction in younger stars, so that some group
galaxies present a higher fraction of them. PCA is more sensitive than other
methods based on a direct analysis of observables such as the structure of the
surface brightness profile or the equivalent width of absorption lines. The
latter do not reveal any significant variation between field and compact group
galaxies. Our results imply that the presence of young stars only amounts to a
fraction of a percent in its contribution to the total variance.Comment: 9 pages, 8 figures. Accepted for publication in MNRA
Granulosa cells express three inositol 1,4,5-trisphosphate receptor isoforms: cytoplasmic and nuclear Ca2+ mobilization
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Verbal Memory and IQ Predict Adaptive Behavior in Children and Adolescents with High-Functioning Autism Spectrum Disorders
Adaptive deficits are commonly found in high functioning autism spectrum disorders (HF-ASD) despite of cognitive potential. Most studies have focused on the relationships between adaptive behavior and intellectual quotient (IQ) and have used correlations to study relationships between them. Few studies have analyzed cognitive variables other than IQ as potential predictors of adaptive behavior in HF-ASD using regression methods. This study aimed to analyze the impact of several cognitive variables on adaptive behavior in a sample of children and adolescents with HF-ASD. METHODS: Sample included 16 child and adolescent boys with HF-ASD (age between 7-17 years). Cognitive assessment included measures of general intelligence, visual memory, verbal memory, working memory and problem solving/flexibility tests. Vineland Adaptive Behavior Scales (VABS) was used to evaluate adaptive behavior. To establish the predictive capacity of the cognitive variables for adaptive functioning, linear regression models were fitted for each adaptive domain using a stepwise method. RESULTS: Verbal memory and IQ emerged as the main independent predictors for VABS adaptive scores. The 41% of the variance in Communication was predicted by IQ. The 35% of the variance in Daily Living Skills was predicted by verbal memory. Almost half of the variance in Socialization was predicted by both, verbal memory and IQ (49%). No other cognitive functions were associated with adaptive scores. CONCLUSIONS: The results highlight the strong impact of IQ and verbal memory on adaptive behavior in HF-ASD patients. These findings could contribute to identify potential targets of intervention
Decreased peripheral health service utilisation during an outbreak of Marburg haemorrhagic fever, UĂge, Angola, 2005.
In 2005, a Marburg haemorrhagic fever (MHF) outbreak occurred in UĂge province, Angola, which had its epicentre in UĂge municipality. Concurrently, a health facility located a considerable distance from the outbreak's epicentre reported a drastic reduction in attendance, possibly due to a remote effect of the ongoing MHF outbreak. Health officials should devise strategies to ensure that communities far from a filovirus haemorrhagic fever epicentre are not adversely affected by interventions at the epicentre and, to the greatest extent possible, ensure that these peripheral communities receive essential medical care during an epidemic
Prehospital neurological deterioration in stroke
BACKGROUND AND PURPOSE:
Patients with stroke can experience neurological deterioration in the prehospital setting. We evaluated patients with stroke to determine factors associated with prehospital neurological deterioration (PND).
METHODS:
Among the Greater Cincinnati/Northern Kentucky region (population ~1.3 million), we screened all 15 local hospitals' admissions from 2010 for acute stroke and included patients aged ≥20. The GCS was compared between emergency medical services (EMS) arrival and hospital arrival, with decrease ≥2 points considered PND. Data obtained retrospectively included demographics, medical history and medication use, stroke subtype (eg, ischaemic stroke (IS), intracerebral haemorrhage (ICH), subarachnoid haemorrhage (SAH)) and IS subtype (eg, small vessel, large vessel, cardioembolic), seizure at onset, time intervals between symptom onset, EMS arrival and hospital arrival, EMS level of training, and blood pressure and serum glucose on EMS arrival.
RESULTS:
Of 2708 total patients who had a stroke, 1092 patients (median (IQR) age 74 (61-83) years; 56% women; 21% black) were analysed. PND occurred in 129 cases (12%), including 9% of IS, 24% of ICH and 16% of SAH. In multivariable analysis, black race, atrial fibrillation, haemorrhagic subtype and ALS level of transport were associated with PND.
CONCLUSION:
Haemorrhage and atrial fibrillation is associated with PND in stroke, and further investigation is needed to establish whether PND can be predicted. Further studies are also needed to assess whether preferential transport of patients with deterioration to hospitals equipped with higher levels of care is beneficial, identify why race is associated with deterioration and to test therapies targeting PND
MAP entropy estimation: applications in robust image filtering
We introduce a new approach for image filtering in a Bayesian framework. In this case the probability density function (pdf) of thelikelihood function is approximated using the concept of non-parametric or kernel estimation. The method is based on the generalizedGaussian Markov random fields (GGMRF), a class of Markov random fields which are used as prior information into the Bayesian rule, whichprincipal objective is to eliminate those effects caused by the excessive smoothness on the reconstruction process of images which arerich in contours or edges. Accordingly to the hypothesis made for the present work, it is assumed a limited knowledge of the noise pdf,so the idea is to use a non-parametric estimator to estimate such a pdf and then apply the entropy to construct the cost function for thelikelihood term. The previous idea leads to the construction of Maximum a posteriori (MAP) robust estimators, since the real systems arealways exposed to continuous perturbations of unknown nature. Some promising results of three new MAP entropy estimators (MAPEE) forimage filtering are presented, together with some concluding remarks
Estudio de las deformidades de la columna vertebral mediante la topografĂa de superficie de la espalda basada en luz estructurada
Actualmente, la prueba “gold estándar” para el diagnóstico de la escoliosis y otras deformidades
de la columna vertebral es la radiografĂa de raquis completo (ángulo de Cobb), pero este mĂ©todo presenta una
serie de limitaciones ya que no caracteriza completamente la deformidad tridimensional del raquis y puede conllevar,
en dosis repetidas, graves riesgos para la salud. Por estos motivos, se presenta un nuevo método óptico,
no invasivo, de topografĂa de superficie de espalda basada en luz estructurada para el estudio de las deformidades
vertebrales, que permite cuantificar las asimetrĂas de la forma de la espalda en los tres planos del espacio
mediante tres variables topográficas: DHOPI, POTSI y PC. Esta tĂ©cnica puede tener gran utilidad clĂnica como
complementaria al estudio radiográficoCurrently the gold standard test for the diagnosis of scoliosis and other spinal deformities is the
full-spine radiograph (Cobb angle). However this method has a number of limitations since it does not fully characterize
the three-dimensional deformation of the spine resulting in some cases, in unnecessary repeated doses,
which could cause serious health risks. Therefore, a new non-invasive optical method to assess the topography
of the back has been developed. This method is based on structured light and it has been used in this study to
evaluate spinal deformities. The method quantifies the asymmetry of the back in three planes of space using
three topographic variables: DHOPI, POTSI and PC. This technique might be of the greatest clinical utility as a
complementary method to the radiographic study
Pepper mild mottle virus in different water matrices
Abstract
Background
Pepper mild mottle virus (PMMoV), a plant virus belonging to Virgoviridae, has recently been suggested as a potential viral indicator for faecal pollution in aquatic environments, since it has been found to be abundantly excreted from healthy human subjects.
Methods
The occurrence, amount and diversity of PMMoV was investigated in water environments by nested RT-PCR and TaqMan based quantitative PCR. During 2017-2019, 251 water samples (92 urban wastewaters, 32 treated effluents, 16 surface water samples, 9 estuarine samples, 20 seawater samples, 67 groundwater samples, and 15 drinking waters) were analysed.
Results
PMMoV was detected in 73/92 (79%) wastewater samples, 22/32 (69%) treated sewages, 11/16 (69%) river samples, 6/9 (67%) estuarine samples, 5/20 (25%) bathing waters, and 9/67 (13%) groundwaters, whilst drinking water samples tested always negative. Mean viral concentrations (genome copies/L) were: raw sewage 4.2 × 106, treated sewage 7.4 × 105, river 3.2 × 103, estuarine waters 9.6 × 102, seawaters 3.0 × 102, groundwaters 7.7 × 101.
Conclusions
This study highlights the significant occurrence of PMMoV in aquatic environment in Italy, and a clear gradient of viral prevalence and concentrations from polluted to clean waters (wastewaters to drinking waters).
Key messages
PMMoV is ubiquitous throughout the water cycle in Italy with different concentrations. Studies are needed to evaluate the suitability of PMMoV as a viral indicator for human fecal pollution in waters
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