847 resultados para sample
Resumo:
Despite strong evidence of high rates of childhood and adult trauma in schizophrenia, the area remains under-researched. Our objectives in the study were first, to examine the rates of exposure to childhood, adult and lifetime (child plus adult) trauma in a population with schizophrenia and a population with non-psychotic psychiatric diagnoses and second, to examine the effect of trauma on the symptoms of schizophrenia. Two groups, those with schizophrenia (n = 40), and those with a non-psychotic diagnosis (n = 30), were recruited. Data were collected for demographic, psychiatric and trauma histories for all participants and on psychosocial functioning and psychiatric symptomatology for the patients with schizophrenia. Childhood exposure to trauma was significantly more common in the schizophrenia group (t = 5.196, df = 68, p <0.001, Eta squared = 0.28), with the strongest relationship being childhood physical assault. In the schizophrenia group a history of trauma was significantly related to poor communication skills (r = -0.529, p <0.001) and depressive symptoms (r = 0.443, p = 0.004). Evidence that childhood exposure to trauma is more common in a population with schizophrenia is consistent with other studies and raises the possibility that such trauma is of etiological importance. Further research is required to replicate those findings, to elucidate possible pathways by which the experience of trauma may contribute to the development of schizophrenia, and to explore the relationship between a history of childhood trauma and the experience of depressive symptoms in schizophrenia.
Resumo:
To understand academic performance of students, the variable of conscientiousness from personality inventory Big Five, has been recognized as an important key. The aim of this paper is to analyze the relationship established between the personality factor conscientiousness itself and two of its facets, laboriousness and planning, with academic performance, and observe if there are genre differences in consciousness personality factor. A total of 456 Spanish students of high school and college participated in the study. They were requested to answer a personality report and a self inform questionnaire. The results show that both conscientiousness as a personality dimension and the consideration of laboriousness facet are able to predict academic performance, especially with regard to student’s exam marks, classroom attendance and dedication to study. The genre variable pointed out that feminine genre is more conscious than male in that personality factor. From a practical perspective, these results indicate that the establishment of a routine of continuous work is suitable for improving student grades and their adaptation to the educational environment.
Resumo:
Background:
The relationship between PTSD and complex PTSD remains unclear. As well as further addressing this issue, the current study aimed to assess the degree to which DESNOS (complex PTSD) was related to interpersonal trauma and had relational consequences.
Methods:
Eighty one treatment-receiving participants with a history of exposure to the ‘Troubles’ in Northern Ireland, were assessed on various forms of interpersonal trauma, including exposure to the Troubles, and measures of interpersonal and community connectedness.
Results:
DESNOS symptom severity was related to childhood sexual abuse and perceived psychological impact of Troubles-related exposure. A lifetime diagnosis of DESNOS was related to childhood Troubles-related experiences, while a current diagnosis of DESNOS was associated with childhood emotional neglect. PTSD avoidance predicted current DESNOS diagnosis and severity. Feeling emotionally disconnected from family and friends (i.e., interpersonal disconnectedness) was related to all three indices of DESNOS (i.e., lifetime diagnosis, current diagnosis and current symptom severity).
Limitations:
Sample characteristics (i.e., treatment-receiving) and size may limit the generalizability of findings.
Conclusions:
Complex PTSD is associated with PTSD but when present should be considered a superordinate diagnosis.
Resumo:
High-resolution optical spectra of 57 Galactic B-type supergiant stars have been analysed to determine their rotational and macroturbulent velocities. In addition, their atmospheric parameters (effective temperature, surface gravity and microturbulent velocity) and surface nitrogen abundances have been estimated using a non-local thermodynamic equilibrium grid of model atmospheres. Comparisons of the projected rotational velocities have been made with the predictions of stellar evolutionary models and in general good agreement was found. However, for a small number of targets, their observed rotational velocities were significantly larger than predicted, although their nitrogen abundances were consistent with the rest of the sample. We conclude that binarity may have played a role in generating their large rotational velocities. No correlation was found between nitrogen abundances and the current projected rotational velocities. However, a correlation was found with the inferred projected rotational velocities of the main-sequence precursors of our supergiant sample. This correlation is again in agreement with the predictions of single star evolutionary models that incorporate rotational mixing. The origin of the macroturbulence and microturbulent velocity fields is discussed and our results support previous theoretical studies that link the former to subphotospheric convection and the latter to non-radial gravity mode oscillations. In addition, we have attempted to identify differential rotation in our most rapidly rotating targets.
Resumo:
The light emission spectrum from a scanning tunnelling microscope (LESTM) is investigated as a function of relative humidity and shown to provide a novel and sensitive means for probing the growth and properties of a water meniscus on the nanometre scale. An empirical model of the light emission process is formulated and applied successfully to replicate the decay in light intensity and spectral changes observed with increasing relative humidity. The modelling indicates a progressive water filling of the tip-sample junction with increasing humidity or, more pertinently, of the volume of the localized surface plasmons responsible for light emission; it also accounts for the effect of asymmetry in structuring of the water molecules with respect to the polarity of the applied bias. This is juxtaposed with the case of a non-polar liquid in the tip-sample nanocavity where no polarity dependence of the light emission is observed. In contrast to the discrete detection of the presence/absence of a water bridge in other scanning probe experiments through measurement of the feedback parameter for instrument control, LESTM offers a means of continuously monitoring the development of the water bridge with sub-nanometre sensitivity. The results are relevant to applications such as dip-pen nanolithography and electrochemical scanning probe microscopy.
Resumo:
This paper examines the finite sample properties of three testing regimes for the null hypothesis of a panel unit root against stationary alternatives in the presence of cross-sectional correlation. The regimes of Bai and Ng (2004), Moon and Perron (2004) and Pesaran (2007) are assessed in the presence of multiple factors and also other non-standard situations. The behaviour of some information criteria used to determine the number of factors in a panel is examined and new information criteria with improved properties in small-N panels proposed. An application to the efficient markets hypothesis is also provided. The null hypothesis of a panel random walk is not rejected by any of the tests, supporting the efficient markets hypothesis in the financial services sector of the Australian Stock Exchange.
Resumo:
The ability to detect harmful algal bloom (HAB) species and their toxins in real- or near real-time is a critical need for researchers studying HAB/toxin dynamics, as well as for coastal resource managers charged with monitoring bloom populations in order to mitigate their wide ranging impacts. The Environmental Sample Processor (ESP), a robotic electromechanical/fluidic system, was developed for the autonomous, subsurface application of molecular diagnostic tests and has successfully detected several HAB species using DNA probe arrays during field deployments. Since toxin production and thus the potential for public health and ecosystem effects varies considerably in natural phytoplankton populations, the concurrent detection of HAB species and their toxins onboard the ESP is essential. We describe herein the development of methods for extracting the algal toxin domoic acid (DA) from Pseudonitzschia cells (extraction efficiency >90%) and testing of samples using a competitive ELISA onboard the ESP. The assay detection limit is in the low ng/mL range (in extract), which corresponds to low ng/L levels of DA in seawater for a 0.5 L sample volume acquired by the ESP. We also report the first in situ detection of both a HAB organism (i.e., Pseudo-nitzschia) and its toxin, domoic acid, via the sequential (within 2-3 h) conduct of species- and toxin-specific assays during ESP deployments in Monterey Bay, CA, USA. Efforts are now underway to further refine the assay and conduct additional calibration exercises with the aim of obtaining more reliable, accurate estimates of bloom toxicity and thus their potential impacts. Published by Elsevier B.V.
Resumo:
Robust associations between the dysbindin gene (DTNBP1) and schizophrenia have been demonstrated in many but not all samples, and evidence that this gene particularly predisposes to negative symptoms in this illness has been presented. The current study sought to replicate the previously reported negative symptom associations in an Irish case-control sample. Association between dysbindin and schizophrenia has been established in this cohort, and a factor analysis of the assessed symptoms yielded three factors, Positive, Negative, and Schneiderian. The sequential addition method was applied using UNPHASED to assess the relationship between these symptom factors and the high-risk haplotype. No associations were detected for any of the symptom factors indicating that the dysbindin risk haplotype does not predispose to a particular group of symptoms in this sample. Several possibilities, such as differing risk haplotypes, may explain this finding. (C) 2009 Wiley-Liss, Inc.
Resumo:
A recent genome-wide association study reported association between schizophrenia and the ZNF804A gene on chromosome 2q32.1. We attempted to replicate these findings in our Irish Case-Control Study of Schizophrenia (ICCSS) sample (N=1021 cases, 626 controls). Following consultation with the original investigators, we genotyped three of the most promising single-nucleotide polymorphisms (SNPs) from the Cardiff study. We replicate association with rs1344706 (trend test one-tailed P=0.0113 with the previously associated A allele) in ZNF804A. We detect no evidence of association with rs6490121 in NOS1 (one-tailed P=0.21), and only a trend with rs9922369 in RGRIP1L (one-tailed P=0.0515). On the basis of these results, we completed genotyping of 11 additional linkage disequilibrium-tagging SNPs in ZNF804A. Of 12 SNPs genotyped, 11 pass quality control criteria and 4 are nominally associated, with our most significant evidence of association at rs7597593 (P=0.0013) followed by rs1344706. We observe no evidence of differential association in ZNF804A on the basis of family history or sex of case. The associated SNP rs1344706 lies in approximately 30 bp of conserved mammalian sequence, and the associated A allele is predicted to maintain binding sites for the brain-expressed transcription factors MYT1l and POU3F1/OCT-6. In controls, expression is significantly increased from the A allele of rs1344706 compared with the C allele. Expression is increased in schizophrenic cases compared with controls, but this difference does not achieve statistical significance. This study replicates the original reported association of ZNF804A with schizophrenia and suggests that there is a consistent link between the A allele of rs1344706, increased expression of ZNF804A and risk for schizophrenia.