638 research outputs found
Neuroanatomical correlates of perceived usability
Usability has a distinct subjective component, yet surprisingly little is known about its neural basis and relation to the neuroanatomy of aesthetics. To begin closing this gap, we conducted two functional magnetic resonance imaging studies in which participants were shown static webpages (in the first study) and videos of interaction with webpages (in the second study). The webpages were controlled so as to exhibit high and low levels of perceived usability and perceived aesthetics. Our results show unique links between perceived usability and brain areas involved in functions such as emotional processing (left fusiform gyrus, superior frontal gyrus), anticipation of physical interaction (precentral gyrus), task intention (anterior cingulate cortex), and linguistic processing (medial and bilateral superior frontal gyri). We use these findings to discuss the brain correlates of perceived usability and the use of fMRI for usability evaluation and for generating new user experiences
MRI Pattern Recognition in Multiple Sclerosis Normal-Appearing Brain Areas
Objective Here, we use pattern-classification to investigate diagnostic information for multiple sclerosis (MS; relapsingremitting type) in lesioned areas, areas of normalappearing grey matter (NAGM), and normal-appearing white matter (NAWM) as measured by standard MR techniques. Methods A lesion mapping was carried out by an experienced neurologist for Turbo Inversion Recovery Magnitude (TIRM) images of individual subjects. Combining this mapping with templates from a neuroanatomic atlas, the TIRM images were segmented into three areas of homogenous tissue types (Lesions, NAGM, and NAWM) after spatial standardization. For each area, a linear Support Vector Machine algorithm was used in multiple local classification analyses to determine the diagnostic accuracy in separating MS patients from healthy controls based on voxel tissue intensity patterns extracted from small spherical subregions of these larger areas. To control for covariates, we also excluded group-specific biases in deformation fields as a potential source of information. Results Among regions containing lesions a posterior parietal WM area was maximally informative about the clinical status (96% accuracy, p<10−13). Cerebellar regions were maximally informative among NAGM areas (84% accuracy, p<10−7). A posterior brain region was maximally informative among NAWM areas (91% accuracy, p<10−10). Interpretation We identified regions indicating MS in lesioned, but also NAGM, and NAWM areas. This complements the current perception that standard MR techniques mainly capture macroscopic tissue variations due to focal lesion processes. Compared to current diagnostic guidelines for MS that define areas of diagnostic information with moderate spatial specificity, we identified hotspots of MS associated tissue alterations with high specificity defined on a millimeter scale
Identifying Trustworthy Experts: How Do Policymakers Find and Assess Public Health Researchers Worth Consulting or Collaborating With?
This paper reports data from semi-structured interviews on how 26 Australian civil servants, ministers and ministerial advisors find and evaluate researchers with whom they wish to consult or collaborate. Policymakers valued researchers who had credibility across the three attributes seen as contributing to trustworthiness: competence (an exemplary academic reputation complemented by pragmatism, understanding of government processes, and effective collaboration and communication skills); integrity (independence, “authenticity”, and faithful reporting of research); and benevolence (commitment to the policy reform agenda). The emphases given to these assessment criteria appeared to be shaped in part by policymakers' roles and the type and phase of policy development in which they were engaged. Policymakers are encouraged to reassess their methods for engaging researchers and to maximise information flow and support in these relationships. Researchers who wish to influence policy are advised to develop relationships across the policy community, but also to engage in other complementary strategies for promoting research-informed policy, including the strategic use of mass media
Nonthermal Emission from Star-Forming Galaxies
The detections of high-energy gamma-ray emission from the nearby starburst
galaxies M82 & NGC253, and other local group galaxies, broaden our knowledge of
star-driven nonthermal processes and phenomena in non-AGN star-forming
galaxies. We review basic aspects of the related processes and their modeling
in starburst galaxies. Since these processes involve both energetic electrons
and protons accelerated by SN shocks, their respective radiative yields can be
used to explore the SN-particle-radiation connection. Specifically, the
relation between SN activity, energetic particles, and their radiative yields,
is assessed through respective measures of the particle energy density in
several star-forming galaxies. The deduced energy densities range from O(0.1)
eV/cm^3 in very quiet environments to O(100) eV/cm^3 in regions with very high
star-formation rates.Comment: 17 pages, 5 figures, to be published in Astrophysics and Space
Science Proceeding
Prolonged Graft Survival in Older Recipient Mice Is Determined by Impaired Effector T-Cell but Intact Regulatory T-Cell Responses
Elderly organ transplant recipients represent a fast growing segment of patients on the waiting list. We examined age-dependent CD4+ T-cell functions in a wild-type (WT) and a transgenic mouse transplant model and analyzed the suppressive function of old regulatory T-cells. We found that splenocytes of naïve old B6 mice contained significantly higher frequencies of T-cells with an effector/memory phenotype (CD4+CD44highCD62Llow). However, in-vitro proliferation (MLR) and IFNγ-production (ELISPOT) were markedly reduced with increasing age. Likewise, skin graft rejection was significantly delayed in older recipients and fewer graft infiltrating CD4+T-cells were observed. Old CD4+ T-cells demonstrated a significant impaired responsiveness as indicated by diminished proliferation and activation. In contrast, old alloantigen-specific CD4+CD25+FoxP3+ T-cells demonstrated a dose-dependent well-preserved suppressor function. Next, we examined characteristics of 18-month old alloreactive T-cells in a transgenic adoptive transfer model. Adoptively transferred old T-cells proliferated significantly less in response to antigen. Skin graft rejection was significantly delayed in older recipients, and graft infiltrating cells were reduced. In summary, advanced recipient age was associated with delayed acute rejection and impaired CD4+ T-cell function and proliferation while CD4+CD25+FoxP3+ T-cells (Tregs) showed a well-preserved function
The splicing regulators Tra and Tra2 are unusually potent activators of pre-mRNA splicing
Sexual differentiation in Drosophila is regulated through alternative splicing of doublesex. Female-specific splicing is activated through the activity of splicing enhancer complexes assembled on multiple repeat elements. Each of these repeats serves as a binding platform for the cooperative assembly of a heterotrimeric complex consisting of the SR proteins Tra, Tra2 and 9G8. Using quantitative kinetic analyses, we demonstrate that each component of the enhancer complex is capable of recruiting the spliceosome. Surprisingly, Tra, Tra2 and 9G8 are much stronger splicing activators than other SR protein family members and their activation potential is significantly higher than expected from their serine/arginine content. 9G8 activates splicing not only through its RS domains but also through its RNA-binding domain. The RS domains of Tra and Tra2 are required but not sufficient for efficient complex assembly. Thus, the regulated assembly of the dsx enhancer complexes leads to the generation of an extended activation domain to guarantee the ‘all or none’ splicing switch that is required during Drosophila sexual differentiation
A Comprehensive Predictive Corrosion Model incorporating varying Environmental Gas Pollutants applied to Wider Steel Applications
A comprehensive model has been developed to predict uniform corrosion rate of structural steel under the effect of low pH conditions for example acid rain. Acid rain is mainly caused by emissions of sulfur dioxide (SO2) which reacts with the water droplets in atmosphere to produce acidic solution which is the primary cause of corrosion of steel structures such as bridges, and weathering of stone buildings and statues. A five-stage division was applied to mathematically describe the model as: (i) the growth rate of air-suspended water droplets (i.e. moisture) depending on the condensation/evaporation rate, (ii) the absorption of gas phase SO2 in the droplets forming bisulfite HSO_3^- ions, (iii) the coalescence of these SO2 absorbed water droplets under the effects of wind speed and gravity, (iv) the deposition rate of SO2 absorbed droplets on steel substrate depending on the inclination and azimuth angles of steel surfaces and, (v) the corrosion rate of steel due to the deposition of these SO2 absorbed droplets. The incorporation of all the above stages develops a comprehensive corrosion prediction model which not only includes the electrochemical parameters but also large number of physical, environmental and material parameters. Experiment was performed to analyse the corrosion rate of steel samples by exposing them to moist SO2 corrosion test. A comparative analysis between the model predictions and experimental results was performed to verify the reliability of model. The predictive trends of corrosion rate of steel were also generated for different values of temperature, relative humidity, and SO2 mole percentage
SR proteins and galectins: what's in a name?
Although members of the serine (S)- and arginine (R)-rich splicing factor family (SR proteins) were initially purified on the basis of their splicing activity in the nucleus, there is recent documentation that they exhibit carbohydrate-binding activity at the cell surface. In contrast, galectins were isolated on the basis of their saccharide-binding activity and cell surface localization. Surprisingly, however, two members (galectin-1 and galectin-3) can be found in association with nuclear ribonucleoprotein complexes including the spliceosome and, using a cell-free assay, have been shown to be required splicing factors. Thus, despite the difference in terms of their original points of interest, it now appears that members of the two protein families share four key properties: (a) nuclear and cytoplasmic distribution; (b) pre-mRNA splicing activity; (c) carbohydrate-binding activity; and (d) cell surface localization in specific cells. These findings provoke stimulating questions regarding the relationship between splicing factors in the nucleus and carbohydrate-binding proteins at the cell surface
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