Controlled synthesis of TiO2 hierarchical nanofibre structures via electrospinning and solvothermal processes : photocatalytic activity for degradation of methylene blue

The present article describes a new titanium oxide‐based (TiO2) photocatalyst that shows promise for acceleration of dye degradation. A hierarchical TiO2 nanostructure comprising nanorods on‐nanofibres has been prepared using a sol&ndash;gel route and electrospinning. Calcination of electrospun nanobre mats was performed in air at 500 &deg;C. The TiO2 nanofibre surface was then exploited as a &lsquo;seeding ground&rsquo; to grow TiO2 nanorods by a solvothermal process in NaOH. The nanofibres had a diameter of approximately 100 nm while the nanorods were evenly distributed on the nanofibre surface with a mean diameter of around 50&ndash;80 nm. The hierarchical nanostructure showed enhanced photocatalytic activity when compared to pure TiO2 nanofibres. This improved efficiency in degrading methylene blue through the photocatalytic process was attributed to the larger specific surface area of the TiO2 nanostructures, as well as high surface‐to‐volume ratio and higher reactive surface resulting in enhanced surface adsorption and interfacial redox reaction.<br /

PlinyCompute: A Platform for High-Performance, Distributed, Data-Intensive Tool Development

This paper describes PlinyCompute, a system for development of high-performance, data-intensive, distributed computing tools and libraries. In the large, PlinyCompute presents the programmer with a very high-level, declarative interface, relying on automatic, relational-database style optimization to figure out how to stage distributed computations. However, in the small, PlinyCompute presents the capable systems programmer with a persistent object data model and API (the "PC object model") and associated memory management system that has been designed from the ground-up for high performance, distributed, data-intensive computing. This contrasts with most other Big Data systems, which are constructed on top of the Java Virtual Machine (JVM), and hence must at least partially cede performance-critical concerns such as memory management (including layout and de/allocation) and virtual method/function dispatch to the JVM. This hybrid approach---declarative in the large, trusting the programmer's ability to utilize PC object model efficiently in the small---results in a system that is ideal for the development of reusable, data-intensive tools and libraries. Through extensive benchmarking, we show that implementing complex objects manipulation and non-trivial, library-style computations on top of PlinyCompute can result in a speedup of 2x to more than 50x or more compared to equivalent implementations on Spark.Comment: 48 pages, including references and Appendi

Deformation modes and anisotropy in magnesium alloy AZ31

A strongly textured sheet of magnesium alloy AZ31 has been subjected to tensile testing at temperatures between ambient and 300&deg;C. Structures have been examined by optical and transmission electron microscopy and also by atomic force microscopy to quantify surface displacements seen at grain boundaries. Plastic anisotropy varies strongly with test temperature as was observed previously by Agnew and Duygulu. The present findings do not support the view that crystallographic &lt;c + a&gt; becomes a major contributor to deformation at higher temperatures. Rather, the material behaviour reflects an increasing contribution from grain boundary sliding despite the relatively high strain rate (I 0-3 s-1) used in the mechanical tests.<br /

Alcohol Perceptions and Behavior in a Residential Peer Social Network

Personalized normative feedback is a recommended component of alcohol interventions targeting college students. However, normative data are commonly collected through campus-based surveys, not through actual participant-referent relationships. In the present investigation, we examined how misperceptions of residence hall peers, both overall using a global question and those designated as important peers using person-specific questions, were related to students’ personal drinking behaviors. Participants were 108 students (88% freshman, 54% White, 51% female) residing in a single campus residence hall. Participants completed an online baseline survey in which they reported their own alcohol use and perceptions of peer alcohol use using both an individual peer network measure and a global peer perception measure of their residential peers. We employed network autocorrelation models, which account for the inherent correlation between observations, to test hypotheses. Overall, participants accurately perceived the drinking of nominated friends but overestimated the drinking of residential peers. Consistent with hypotheses, overestimating nominated friend and global residential peer drinking predicted higher personal drinking, although perception of nominated peers was a stronger predictor. Interaction analyses showed that the relationship between global misperception and participant self-reported drinking was significant for heavy drinkers, but not non-heavy drinkers. The current findings explicate how student perceptions of peer drinking within an established social network influence drinking behaviors, which may be used to enhance the effectiveness of normative feedback interventions

Randomized double-blind placebo-controlled trial of 40 mg/day of atorvastatin in reducing the severity of sepsis in ward patients (ASEPSIS Trial)

Introduction: Several observational studies suggest that statins modulate the pathophysiology of sepsis and may prevent its progression. The aim of this study was to determine if the acute administration of atorvastatin reduces sepsis progression in statin naïve patients hospitalized with sepsis. Methods: A single centre phase II randomized double-blind placebo-controlled trial. Patients with sepsis were randomized to atorvastatin 40 mg daily or placebo for the duration of their hospital stay up to a maximum of 28-days. The primary end-point was the rate of sepsis progressing to severe sepsis during hospitalization. Results: 100 patients were randomized, 49 to the treatment with atorvastatin and 51 to placebo. Patients in the atorvastatin group had a significantly lower conversion rate to severe sepsis compared to placebo (4% vs. 24% p = 0.007.), with a number needed to treat of 5. No significant difference in length of hospital stay, critical care unit admissions, 28-day and 12-month readmissions or mortality was observed. Plasma cholesterol and albumin creatinine ratios were significantly lower at day 4 in the atorvastatin group (p < 0.0001 and p = 0.049 respectively). No difference in adverse events between the two groups was observed (p = 0.238). Conclusions: Acute administration of atorvastatin in patients with sepsis may prevent sepsis progression. Further multi-centre trials are required to verify these findings. Trial Registration: International Standard Randomized Control Trial Registry ISRCTN64637517

Spatial Structure and Collisionless Electron Heating in Balmer-dominated Shocks

Balmer-dominated shocks in supernova remnants (SNRs) produce strong hydrogen lines with a two-component profile composed of a narrow contribution from cold upstream hydrogen atoms, and a broad contribution from hydrogen atoms that have undergone charge transfer reactions with hot protons. Observations of emission lines from edge-wise shocks in SNRs can constrain the gas velocity and collisionless electron heating at the shock front. Downstream hydrogen atoms engage in charge transfer, excitation and ionization reactions, defining an interaction region called the shock transition zone. The properties of hot hydrogen atoms produced by charge transfers (called broad neutrals) are critical for accurately calculating the structure and radiation from the shock transition zone. This paper is the third in a series describing the kinetic, fluid and emission properties of Balmer-dominated shocks, and is the first to properly treat the effect of broad neutral kinetics on shock transition zone structure. We use our models to extract shock parameters from observations of Balmer-dominated SNRs. We find that inferred shock velocities and electron temperatures are lower than those of previous calculations by <10% for v_s<1500 km/s, and by 10-30% for v_s>1500 km/s. This effect is primarily due to the fact that excitation by proton collisions and charge transfer to excited levels favor the high speed part of the neutral hydrogen velocity distribution. Our results have a strong dependence on the ratio of electron to proton temperatures, \beta=T_e/T_p, which allows us to construct a relation \beta(v_s) between the temperature ratio and shock velocity. We compare our calculations to previous results by Ghavamian et al. (2007).Comment: 41 pages, 15 figures, 2 tables. Improved comparison to previous results, added discussion, and incorporated referee's suggestions. Submitted to Ap

Information technology in support of research, scholarship, and creative activities: A strategic plan for Research Technologies – a division of UITS and a PTI Service and Cyberinfrastructure Center

Stewart, C.A., M.R. Link, E. Wernert, W.K. Barnett, T.M. Miller. 2012. Information technology in support of research, scholarship, and creative activities: A strategic plan for Research Technologies – a division of UITS and a PTI Service and Cyberinfrastructure Center. Indiana University, Bloomington, IN. PTI Technical Report PTI-TR12-007.IU is currently executing its second information technology strategic plan – Empowering People: Indiana University's Strategic Plan for Information Technology 2009 (hereafter referred to as Empowering People). In this document, we set out long-term goals for the Research Technologies (RT) division of UITS, reaffirm specific goals set for RT for 2019, describe Actions within Empowering People for which RT is responsible, and describe the new internal structure of Research Technologies. The mission of the Research Technologies division of UITS is to develop, deliver, and support advanced technology solutions that improve productivity of and enable new possibilities in research, scholarly endeavors, and creative activity at Indiana University and beyond; and to complement this with education and technology translation activities to improve the quality of life of people in Indiana, the nation, and the world

A comparison of the effects of manual hyperinflation and ventilator hyperinflation on restoring end-expiratory lung volume after endotracheal suctioning: a pilot physiologic study

Purpose: Endotracheal suctioning (ES) of mechanically ventilated patients decreases end-expiratory lung volume (EELV). Manual hyperinflation (MHI) and ventilator hyperinflation (VHI) may restore EELV post-ES but it remains unknown which method is most effective. The primary aim was to compare the efficacy of MHI and VHI in restoring EELV post-ES. Materials and methods: ES was performed on mechanically ventilated intensive care patients, followed by MHI or VHI, in a randomised crossover design. The washout period between interventions was 1 h. End-expiratory lung impedance (EELI), measured by electrical impedance tomography, was recorded at baseline, during ES, during hyperinflation and 1, 5, 15 and 30 min post-hyperinflation. Results: Nine participants were studied. ES decreased EELI by 1672z (95% CI, 1204 to 2140) from baseline. From baseline, MHI increased EELI by 1154z (95% CI, 977 to 1330) while VHI increased EELI by 769z (95% CI, 457 to 1080). Five minutes post-VHI, EELI remained 528z (95% CI, 4 to 1053) above baseline. Fifteen minutes post-MHI, EELI remained 351z (95% CI, 111 to 592) above baseline. At subsequent time-points, EELI returned to baseline. Conclusions: MHI and VHI effectively restore EELV above baseline post-ES and should be considered post suctioning

Enrollment and Assessment of a First-Year College Class Social Network for a Controlled Trial of the Indirect Effect of a Brief Motivational Intervention

Heavy drinking and its consequences among college students represent a serious public health problem, and peer social networks are a robust predictor of drinking-related risk behaviors. In a recent trial, we administered a Brief Motivational Intervention (BMI) to a small number of first-year college students to assess the indirect effects of the intervention on peers not receiving the intervention. Objectives: To present the research design, describe the methods used to successfully enroll a high proportion of a first-year college class network, and document participant characteristics. Methods: Prior to study enrollment, we consulted with a student advisory group and campus stakeholders to aid in the development of study-related procedures. Enrollment and baseline procedures were completed in the first six weeks of the academic semester. Surveys assessed demographics, alcohol use, and social network ties. Individuals were assigned to a BMI or control group according to their dormitory location. Results: The majority of incoming first-year students (1342/1660; 81%) were enrolled (55% female, 52% nonwhite, mean age 18.6 [SD = 0.51]). Differences between the intervention and control group were noted in alcohol use, but were in large part a function of there being more substance-free dormitory floors in the control group. Conclusions: The current study was successful in enrolling a large proportion of a first-year college class and can serve as a template for social network investigations