4,131 research outputs found
Development of the Variable Dexterity Test: construction, reliability and validity
Background/Aims: This article introduces a dexterity test designed to assess individual types of
dexterity used to carry out activities of daily living (ADL). The Variable Dexterity Test (VDT) was
developed as part of a wider study, the broader aim being to fully understand dexterity and its effect
on human-product interaction during ADL. This was done with a view to improve occupational therapy
methods when assessing dexterity and general hand function.
Methods: The control group consisted of 24 healthy participants. Estimates of reliability and validity
were evaluated in this pilot study. Inter-rater and test-retest reliability were assessed using a one-way
ANOVA. The validity of the test was estimated by correlating participantsâ VDT scores with their
proficiency to complete four ADL task actions and a standardised dexterity test (Purdue Pegboard Test).
Results: The test produced consistent results among the control group with both a single assessor
(testâretest reliability) and multiple assessors (interârater reliability). High correlations between
participantsâ VDT scores and proficiency to perform ADL were found for most of the subtests. There
was also a high correlation between participantsâ scores from the Purdue Pegboard Test and the VDT.
Conclusions: The VDT proved to be a flexible, reliable and valid tool that assesses dexterity based on
ability to carry out ADL. Validity and reliability estimates show encouraging values, which recognises
that the VDT can be used as an accurate method to assess more than one type of dexterity.</p
Common Genetic Variants Explain the Majority of the Correlation Between Height and Intelligence : The Generation Scotland Study
Creative Commons Attribution LicensePeer reviewedPublisher PD
Convergence to stable laws for multidimensional stochastic recursions: the case of regular matrices
Given a sequence of i.i.d.\ random variables with
generic copy , we consider the random
difference equation (RDE) , and assume
the existence of such that \lim_{n \to \infty}(\E{\norm{M_1 ...
M_n}^\kappa})^{\frac{1}{n}} = 1 . We prove, under suitable assumptions, that
the sequence , appropriately normalized, converges in
law to a multidimensional stable distribution with index . As a
by-product, we show that the unique stationary solution of the RDE is
regularly varying with index , and give a precise description of its
tail measure. This extends the prior work http://arxiv.org/abs/1009.1728v3 .Comment: 15 page
Linear and nonlinear optical spectroscopy of a strongly-coupled microdisk-quantum dot system
A fiber taper waveguide is used to perform direct optical spectroscopy of a
microdisk-quantum-dot system, exciting the system through the photonic (light)
channel rather than the excitonic (matter) channel. Strong coupling, the regime
of coherent quantum interactions, is demonstrated through observation of vacuum
Rabi splitting in the transmitted and reflected signals from the cavity. The
fiber coupling method also allows the examination of the system's steady-state
nonlinear properties, where saturation of the cavity-QD response is observed
for less than one intracavity photon.Comment: adjusted references, added minor clarification
SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables
We present a SOFIA FORCAST grism spectroscopic survey to examine the mineralogy of the circumstellar dust
in a sample of post-asymptotic giant branch (post-AGB) yellow supergiants that are believed to be the precursors
of planetary nebulae. Our mineralogical model of each star indicates the presence of both carbon-rich and oxygenrich dust speciesâcontrary to simple dredge-up modelsâwith a majority of the dust in the form of amorphous
carbon and graphite. The oxygen-rich dust is primarily in the form of amorphous silicates. The spectra do not
exhibit any prominent crystalline silicate emission features. For most of the systems, our analysis suggests that the
grains are relatively large and have undergone significant processing, supporting the hypothesis that the dust is
confined to a Keplerian disk and that we are viewing the heavily processed, central regions of the disk from a
nearly face-on orientation. These results help to determine the physical properties of the post-AGB circumstellar
environment and to constrain models of post-AGB mass loss and planetary nebula formatio
Influenza infection and risk of acute pulmonary embolism
<p>Abstract</p> <p>Background</p> <p>Influenza infections have been associated with procoagulant changes. Whether influenza infections lead to an increased risk of pulmonary embolism remains to be established.</p> <p>Methods</p> <p>We conducted a nested case control study in a large cohort of patients with a clinical suspicion of having pulmonary embolism. Blood samples were collected to investigate the presence of influenza A and B by complement fixation assay (CFA). We compared case patients, in whom pulmonary embolism was proven (n = 102), to controls, in whom pulmonary embolism was excluded (n = 395). Furthermore, we compared symptoms of influenza-like illness in both patient groups 2 weeks prior to inclusion in the study, using the influenza-like illness (ILI) score, which is based on a questionnaire. We calculated the risk of pulmonary embolism associated with influenza infection.</p> <p>Results</p> <p>The percentage of patients with influenza A was higher in the control group compared to the case group (4.3% versus 1.0%, respectively, odds ratio 0.22; 95% CI: 0.03â1.72). Influenza B was not detectable in any of the cases and was found in 3 of the 395 controls (0.8%). The ILI score was positive in 24% of the cases and 25% in the control persons (odds ratio 1.16, 95% CI: 0.67â2.01). We did not observe an association between the ILI score and proven influenza infection.</p> <p>Conclusion</p> <p>In this clinical study, influenza infection was not associated with an increased risk of acute pulmonary embolism. The ILI score is non-specific in this clinical setting.</p
Influence of laser shock peening on the residual stresses in additively manufactured 316L by Laser Powder Bed Fusion: A combined experimental-numerical study
Detrimental subsurface tensile residual stresses occur in laser powder bed fusion (LPBF) due to significant temperature gradients during the process. Besides heat treatments, laser shock peening (LSP) is a promising technology for tailoring residual stress profiles of additively manufactured components. A multi step process simulation is applied aiming at predicting the residual stress state after applying LSP to a cuboid shaped specimen manufactured by LPBF in two different building directions as well as comparing it with a post-build heat treatment. The validity of the numerical simulation is evaluated based on comparisons of residual stresses determined by incremental hole drilling technique within different stages of the multi step process: in the as-build condition, after subsequent heat treatment as well as after applying LSP to the as-build and heat treated specimens, showing overall a good experimentalânumerical agreement throughout each of the process stages. Applying a heat treatment to the as-build LPBF sample at 700 °C for 6 h showed not to be effective in eliminating the surface tensile stress entirely, reducing the tensile residual stresses by 40%. However, the application of LSP on LPBF components showed promising results: LSP was able even to convert the detrimental near surface tensile residual stresses in the LPBF component into compressive residual stresses next to the surface, which is known to be beneficial for the fatigue performance
POZ-, AT-hook-, and Zinc Finger-containing Protein (PATZ) Interacts with Human Oncogene B Cell Lymphoma 6 (BCL6) and Is Required for Its Negative Autoregulation.
The PATZ1 gene encoding a POZ/AT-hook/Kruppel zinc finger (PATZ) transcription factor, is considered a cancer-related gene because of its loss or misexpression in human neoplasias. As for other POZ/domain and Kruppel zinc finger (POK) family members, the transcriptional activity of PATZ is due to the POZ-mediated oligomer formation, suggesting that it might be not a typical transactivator but an architectural transcription factor, thus functioning either as activator or as repressor depending on the presence of proteins able to interact with it. Therefore, to better elucidate PATZ function, we searched for its molecular partners. By yeast two-hybrid screenings, we found a specific interaction between PATZ and BCL6, a human oncogene that plays a key role in germinal center (GC) derived neoplasias. We demonstrate that PATZ and BCL6 interact in germinal center-derived B lymphoma cells, through the POZ domain of PATZ. Moreover, we show that PATZ is able to bind the BCL6 regulatory region, where BCL6 itself acts as a negative regulator, and to contribute to negatively modulate its activity. Consistently, disruption of one or both Patz1 alleles in mice causes focal expansion of thymus B cells, in which BCL6 is up-regulated. This phenotype was almost completely rescued by crossing Patz1(+/-) with Bcl6(+/-) mice, indicating a key role for Bcl6 expression in its development. Finally, a significant number of Patz1 knock-out mice (both heterozygous and homozygous) also develop BCL6-expressing lymphomas. Therefore, the disruption of one or both Patz1 alleles may favor lymphomagenesis by activating the BCL6 pathway
Escherichia coli induces apoptosis and proliferation of mammary cells
Mammary cell apoptosis and proliferation were assessed after injection of Escherichia coli into the left mammary quarters of six cows. Bacteriological analysis of foremilk samples revealed coliform infection in the injected quarters of four cows. Milk somatic cell counts increased in these quarters and peaked at 24 h after bacterial injection. Body temperature also increased, peaking at 12 h postinjection, The number of apoptotic cells was significantly higher in the mastitic tissue than in the uninfected control. Expression of Bax and interleukin-1 beta converting enzyme increased in the mastitic tissue at 24 h and 72 h postinfection, whereas Bcl-2 expression decreased at 24 h but did not differ significantly from the control at 72 h postinfection, Induction of matrix metalloproteinase-g, stromelysin-1 and urokinase-type plasminogen activator was also observed in the mastitic tissue. Moreover, cell proliferation increased in the infected tissue, These results demonstrate that Escherichia coli-induced mastitis promotes apoptosis and cell proliferation
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