1,040 research outputs found
Attention and associative learning in humans: An integrative review
This article presents a comprehensive survey of research concerning interactions between associative learning and attention in humans. Four main findings are described. First, attention is biased toward stimuli that predict their consequences reliably (learned predictiveness). This finding is consistent with the approach taken by Mackintosh (1975) in his attentional model of associative learning in nonhuman animals. Second, the strength of this attentional bias is modulated by the value of the outcome (learned value). That is, predictors of high-value outcomes receive especially high levels of attention. Third, the related but opposing idea that uncertainty may result in increased attention to stimuli (Pearce & Hall, 1980), receives less support. This suggests that hybrid models of associative learning, incorporating the mechanisms of both the Mackintosh and Pearce-Hall theories, may not be required to explain data from human participants. Rather, a simpler model, in which attention to stimuli is determined by how strongly they are associated with significant outcomes, goes a long way to account for the data on human attentional learning. The last main finding, and an exciting area for future research and theorizing, is that learned predictiveness and learned value modulate both deliberate attentional focus, and more automatic attentional capture. The automatic influence of learning on attention does not appear to fit the traditional view of attention as being either goal-directed or stimulus-driven. Rather, it suggests a new kind of “derived” attention
Multiple imputation of missing covariates for the Cox proportional hazards cure model
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134146/1/sim7048_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134146/2/sim7048.pd
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The peripheral blood transcriptome in septic cardiomyopathy: an observational, pilot study.
BACKGROUND:Septic cardiomyopathy (SCM) is common in sepsis and associated with increased morbidity and mortality. Left ventricular global longitudinal strain (LV GLS), measured by speckle tracking echocardiography, allows improved identification of impaired cardiac contractility. The peripheral blood transcriptome may be an important window into SCM pathophysiology. We therefore studied the peripheral blood transcriptome and LV GLS in a prospective cohort of patients with sepsis. RESULTS:In this single-center observational pilot study, we enrolled adult patients (age > 18) with sepsis within 48 h of admission to the ICU. SCM was defined as LV GLS > - 17% based on echocardiograms performed within 72 h of admission. We enrolled 27 patients, 24 of whom had high-quality RNA results; 18 (75%) of 24 had SCM. The group was 50% female and had a median (IQR) age of 59.5 (48.5-67.0) years and admission APACHE II score of 21.0 (16.0-32.3). Forty-six percent had septic shock. After filtering for low-expression and non-coding genes, 15,418 protein coding genes were expressed and 73 had significantly different expression between patients with vs. without SCM. In patients with SCM, 43 genes were upregulated and 30 were downregulated. Pathway analysis identified enrichment in type 1 interferon signaling (adjusted p < 10-5). CONCLUSIONS:In this hypothesis-generating study, SCM was associated with upregulation of genes in the type 1 interferon signaling pathway. Interferons are cytokines that stimulate the innate and adaptive immune response and are implicated in the early proinflammatory and delayed immunosuppression phases of sepsis. While type 1 interferons have not been implicated previously in SCM, interferon therapy (for viral hepatitis and Kaposi sarcoma) has been associated with reversible cardiomyopathy, perhaps suggesting a role for interferon signaling in SCM
High-throughput synthesis and characterization of BiMoVOX materials
The high throughput synthesis and characterization of a particular family of ceramic materials, bismuth
molybdenum vanadium oxides (BiMoVOX), suitable as inorganic yellow pigments and low temperature oxidation
catalysts, is described. Samples, synthesized by calcination and peroxo sol-gel methods, are characterized by X-ray
powder diffraction, UV-visible and XAFS spectroscopy. A combined high-throughput XRD/XAFS study of a 54
samples array, with simultaneous refinement of data of both techniques, has been performed. Molybdenum doping of
bismuth vanadate results in a phase transition from monoclinic BiV04 to tetragonal Bi(V,Mo)04, both of scheelite type.
Both central metals, V5+ and Mo6+, remain in a tetrahedral coordination. UV/visible spectroscopy identifies a linear blue
shift as a function of Mo6+ amount
Effects of biochar amendment on root traits and contaminant availability of maize plants in a copper and arsenic impacted soil
Biochar has been proposed as a tool to enhance phytostabilisation of contaminated soils but little data are available to illustrate the direct effect on roots in contaminated soils. This work aimed to investigate specific root traits and to assess the effect of biochar amendment on contaminant availability. Amendment with two different types of biochar, pine woodchip and olive tree pruning, was assessed in a rhizobox experiment with maize planted in a soil contaminated with significant levels of copper and arsenic. Amendment was found to significantly improve root traits compared to the control soil, particularly root mass density and root length density. Copper uptake to plants and ammonium sulphate extractable copper was significantly less in the biochar amended soils. Arsenic uptake and extractability varied with type of biochar used but was not considered to be the limiting factor affecting root and shoot development. Root establishment in contaminated soils can be enhanced by biochar amendment but choice of biochar is key to maximising soil improvement and controlling contaminant availability
Predicting the effects of biochar on volatile petroleum hydrocarbon biodegradation and emanation from soil: a bacterial community finger-print analysis inferred modelling approach
We investigated the response of the dominant bacterial taxa in gravelly sand to the addition of biochar and/or mixtures of volatile petroleum hydrocarbons (VPHs) using denaturing gradient gel electrophoresis (DGGE) and sequencing of cut bands. Biochar addition alone had only weak effects on the soil bacterial community composition in batch study samples, while VPH addition had strong effects. Indirect effects of biochar on soil bacterial communities were apparent in column study samples, where biochar-enhanced sorption affected VPH spreading. Following VPH addition, cell abundance increased by no more than a factor of 2 and several Pseudomonas spp. became dominant in soil with and without biochar. We present a VPH fate model that considers soil bacterial biomass dynamics and a nutrient limited soil biomass carrying capacity. The model simulates an apparent lag phase before the onset of a brief period of intensive VPH biodegradation and biomass growth, which is followed by substantially slower VPH biodegradation, when nitrogen needs to be recycled between decaying and newly formed biomass. If biomass growth is limited by a factor other than the organic pollutant bioavailability, biochar amendment may enhance VPH attenuation in between a VPH source below ground and the atmosphere by reducing the risk of overloading the soil's biodegradation capacity
Individualized outcome prognostication for patients with laryngeal cancer
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142424/1/cncr31087.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142424/2/cncr31087_am.pd
The supportive care needs of women experiencing gynaecological cancer: a Western Australian cross-sectional study
Background: Women diagnosed with gynaecological cancer experience supportive care needs that require care provision to reduce the impact on their lives. International evidence suggests supportive care needs of women with gynaecological cancer are not being met and provision of holistic care is a priority area for action. Knowledge on gynaecological cancer supportive care needs is limited, specifically comparison of needs and cancer gynaecological subtype. Our aim was to identify supportive care needs of Western Australian women experiencing gynaecological cancer, their satisfaction with help and explore associations between participant’s demographic characteristics and identified needs. Methods: A cross-sectional design incorporating a modified version of the Supportive Care Needs Survey - short form (SCNS-SF34) assessed 37 supportive care needs under five domains in conjunction with demographic data. Three hundred and forty three women with gynaecological cancer attending a tertiary public referral hospital completed the survey over 12 months. Statistical analysis was performed using the R environment for statistical computing. A linear regression model was fitted with factor scores for each domain and demographic characteristics as explanatory variables. Results: Three hundred and three women (83%) identified at least one moderate or high level supportive care need. The five highest ranked needs were, ‘being informed about your test results as soon as feasible’ (54.8%), ‘fears about cancer spreading’ (53.7%), ‘being treated like a person not just another case’ (51.9%), ‘being informed about cancer which is under control or diminishing (that is, remission)’ (50.7%), and ‘being adequately informed about the benefits and side-effects of treatments before you choose to have them’ (49.9%). Eight of the top ten needs were from the ‘health system and information’ domain. Associations between supportive care items and demographic variables revealed ‘cancer type’, and ‘time since completion of treatment’ had no impact on level of perceived need for any domain. Conclusions: Western Australian women with gynaecological cancer identified a high level of supportive care needs. The implementation of a supportive care screening tool is recommended to ensure needs are identified and care is patient-centred. Early identification and management of needs may help to reduce the burden on health system resources for managing ongoing needs
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