Bayesian nonstationary autoregressive models for biomedical signal analysis

We describe a variational Bayesian algorithm for the estimation of a multivariate autoregressive model with time-varying coefficients that adapt according to a linear dynamical system. The algorithm allows for time and frequency domain characterization of nonstationary multivariate signals and is especially suited to the analysis of event-related data. Results are presented on synthetic data and real electroencephalogram data recorded in event-related desynchronization and photic synchronization scenarios.     

Recent advances in titanium dioxide/graphene photocatalyst materials as potentials of energy generation

The properties of titanium dioxide (\(\hbox {TiO}_{2})\)/graphene/graphene oxides (GO) are examined in this study. These views summarize the recent theoretical and experimental novel approaches in the catalytic activity of \(\hbox {TiO}_{2}\)/graphene interface. Imperative results at a level of detail, suitable for upcoming experimental and theoretical researchers involved an overview of the enthralling characteristics of \(\hbox {TiO}_{2}\) and graphene composites were presented. Aspects like crystal lattice, electronic band structure and phonon dispersion, among others that were used to describe the properties of a \(\hbox {TiO}_{2}\) interface with pristine graphene and graphene dioxide among other composites are discussed. In particular, this review covers reactivity, binding energies, geometric structures as well as the photocatalytic activity of anatase \(\hbox {TiO}_{2}\) surfaces with graphene and graphene oxide with hybrid nanocomposites. These views also explore the understanding of the \(\hbox {TiO}_{2}\) interactions with graphene and possible applications. Finally, highlights on the challenges and proposed strategies in developing advanced photocatalytic semiconductor-based composites for water-splitting applications are provided.     

Thrombotic events and markers of oxidation and inflammation in hemodialysis

The goal of this study was to determine whether antioxidant therapy with vitamin E would alter the rate of vascular access complications or other macrovascular complications in hemodialysis (HD) patients. A secondary goal of the study was to explore the relationship between baseline pretreatment markers of oxidative stress (the advanced glycation end product pentosidine and basal levels of vitamin Eα and γ) and the subsequent development of access failure. Thirty‐five stable patients treated by HD were recruited for the study. Patients were provided with vitamin E (800 IU) or placebo capsules to be taken daily. Clinical variables, vascular access function (flow meter access flow measurements), and circulating blood markers were obtained initially and every 3 months throughout the study. Vitamin Eα levels rose in treated patients from 12.7 ± 4.4 to 25.1 ± 15.1 µg/mL at 3 months and 28.6 ± 14.8 µg/mL at 6 months. Vitamin Eγ levels fell in treated patients from 3.9 ± 1.7 to 2.3 ± 1.5 µg/mL at 3 months and 1.7 µg/mL at 6 months. Patients who subsequently developed repeated thrombotic vascular access events were characterized by higher baseline pentosidine content of circulating proteins. Patients who developed a myocardial infarction had higher pentosidine, lower vitamin Eα, and much lower vitamin Eγ than patients who did not develop thrombotic events. These findings lead to the speculation that the anti‐inflammatory effects of vitamin Eγ may play a more important role in thrombotic vascular events than the antioxidant effects of vitamin Eα. Additional studies of these interactions are in progress.     

Evaluation of illustration‐inspired techniques for time‐varying data visualization

Illustration‐inspired techniques have provided alternative ways to visualize time‐varying data. Techniques such as speedlines, flow ribbons, strobe silhouettes and opacity‐based techniques provide temporal context to the current timestep being visualized. We evaluated the effectiveness of these illustrative techniques by conducting a user study. We compared the ability of subjects to visually track features using snapshots, snapshots augmented by illustration techniques, animations, and animations augmented by illustration techniques. User accuracy, time required to perform a task, and user confidence were used as measures to evaluate the techniques. The results indicate that the use of illustration‐inspired techniques provides a significant improvement in user accuracy and the time required to complete the task. Subjects performed significantly better on each metric when using augmented animations as compared to augmented snapshots.     

The shelf life of chilled sheep livers packed in closed tubs

Livers incubated at 30°C in closed tubs developed floras dominated by Enterobacteriaceae. At chiller temperatures, floras were ultimately dominated by psychrotrophic lactobacilli. Tub-packed livers can have an extended shelf life similar to that reported for vacuum-packed liver.     

How Surveillance Begets Perceptions of Dishonesty: The Case of the Counterfactual Sinner.

Three studies support the hypothesis that observers' impressions of actors reflect not only what actors do but also what they can easily be imagined doing. Participants in Studies 1 and 2 observed a 10-year-old boy take a math test in a context in which the incentive to cheat and the constraints against cheating varied. When the incentive to cheat was high but the likelihood of getting caught was also high, observers perceived a target who resisted the temptation to cheat as less honest than the average boy. This effect was not found when the incentive to cheat was low, which suggests that its occurrence under high temptation resulted from observers in that condition generating the counterfactual thought that the target would have cheated had the likelihood of detection been low. Study 3 further supported the link between spontaneous counterfactual thought and inferences of dishonesty. The implications of the counterfactual correspondence bias are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Strategies for CO2 capture from different CO2 emission sources by vacuum swing adsorption technology☆

Different VSA(Vacuum Swing Adsorption) cycles and process schemes have been evaluated to find suitable process configurations for effectively separating CO2 from flue gases from different industrial sectors. The cycles were studied using an adsorption simulator developed in our research group, which has been successfully used to predict experimental results over several years. Commercial zeolite APGIII and granular activated carbon were used as the adsorbents. Three-bed VSA cycles with- and without-product purge and 2-stage VSA systems have been investigated. It was found that for a feed gas containing 15% CO2(representing flue gas from power plants), high CO2 purities and recoveries could be obtained using a three-bed zeolite APGIII VSA unit for one stage capture, but with more stringent conditions such as deeper vacuum pressures of 1–3 k Pa. 2-stage VSA process operated in series allowed us to use simple process steps and operate at more realistic vacuum pressures. With a vacuum pressure of 10 k Pa, final CO2 purity of 95.3% with a recovery of 98.2% were obtained at specific power consumption of 0.55 MJ·(kg CO2)-1from feed gas containing15% CO2. These numbers compare very well with those obtained from a single stage process operating at1 k Pa vacuum pressure. The feed CO2 concentration was very influential in determining the desorption pressure necessary to achieve high separation efficiency. For feed gases containing N 30% CO2, a singlestage VSA capture process operating at moderate vacuum pressure and without a product purge, can achieve very high product purities and recoveries.     

Speech perception, vocabulary, and the development of reading skills in english among Korean- and English-speaking children.

This study examined the roles of speech perception and phonological processing in reading and spelling acquisition for native and nonnative speakers of English in the 1st grade. The performance of 50 children (23 native English speakers and 27 native Korean speakers) was examined on tasks assessing reading and spelling, phonological processing, speech perception, and receptive vocabulary at the start and end of the school year. Korean-speaking children outperformed native English speakers on each of the literacy measures at the start and end of 1st grade, despite differences in their initial phonological representations and processing skills. Furthermore, speech perception and phonological processing were important contributors to early literacy skills, independent of oral language skills, for children from both language groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attitude Importance and the Accumulation of Attitude-Relevant Knowledge in Memory.

People who attach personal importance to an attitude are especially knowledgeable about the attitude object. This article tests an explanation for this relation: that importance causes the accumulation of knowledge by inspiring selective exposure to and selective elaboration of relevant information. Nine studies showed that (a) after watching televised debates between presidential candidates, viewers were better able to remember the statements made on policy issues on which they had more personally important attitudes; (b) importance motivated selective exposure and selective elaboration: Greater personal importance was associated with better memory for relevant information encountered under controlled laboratory conditions, and manipulations eliminating opportunities for selective exposure and selective elaboration eliminated the importance-memory accuracy relation; and (c) people do not use perceptions of their knowledge volume to infer how important an attitude is to them, but importance does cause knowledge accumulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)