A small-scale comparison of the equivalence of paper-and-pencil and computerized versions of student end-of-course evaluations

This study compared responses to two versions of an end-of-course evaluation instrument completed by graduate students: the traditional printed form completed using pencil and paper, and a microcomputer-based form that presented equivalent items and accepted student responses. A finding of no significant difference in favorableness of composite ratings between the two versions prompted the researcher to perform item-by-item analyses of the two instruments. These analyses revealed that ratings of the individual items on one instrument were highly correlated with the ratings of their matched corresponding items on the other instrument. The paper-and-pencil and computerized evaluation instruments were found to be of almost identically high reliability. Possible limitations of the findings and areas for future research are discussed.     

EU renewable energy support policy: Faith or facts?

The recent EU Commission proposal for promoting the supply of power from renewable energy sources was originally based on a pan-European, harmonised tradable green certificate (TGC) scheme. We suggest, on the basis of a multi-disciplinary analysis, that a pan-EU TGC system is not the way forward for Europe. It is vital that the Commission (and the majority of Member States) avoids implementation of such policy designs put forward by a coalition of vested interests. They should instead look at, and act upon, the available evidence from those countries that have experimented with TGCs (e.g. Flanders, UK and Sweden) and design policies that stand a better chance of meeting the criteria of effectiveness, efficiency and equity. In particular, the policies must enable EU to meet the immense innovation/industrialisation challenge by inducing the development of a capital goods industry that can, eventually, diffuse a broad range of technologies that use renewable energy sources. Only then we can acquire an ability to implement an industrial revolution in the energy system in a way that broadly meets the criteria of effectiveness and dynamic efficiency.     

Hierarchical virtual screening for the discovery of new molecular scaffolds in antibacterial hit identification

One of the initial steps of modern drug discovery is the identification of small organic molecules able to inhibit a target macromolecule of therapeutic interest. A small proportion of these hits are further developed into lead compounds, which in turn may ultimately lead to a marketed drug. A commonly used screening protocol used for this task is high-throughput screening (HTS). However, the performance of HTS against antibacterial targets has generally been unsatisfactory, with high costs and low rates of hit identification. Here, we present a novel computational methodology that is able to identify a high proportion of structurally diverse inhibitors by searching unusually large molecular databases in a time-, cost- and resource-efficient manner. This virtual screening methodology was tested prospectively on two versions of an antibacterial target (type II dehydroquinase from Mycobacterium tuberculosis and Streptomyces coelicolor), for which HTS has not provided satisfactory results and consequently practically all known inhibitors are derivatives of the same core scaffold. Overall, our protocols identified 100 new inhibitors, with calculated K_i ranging from 4 to 250 μM (confirmed hit rates are 60% and 62% against each version of the target). Most importantly, over 50 new active molecular scaffolds were discovered that underscore the benefits that a wide application of prospectively validated in silico screening tools is likely to bring to antibacterial hit identification.     

Spiritual struggle related to plasma interleukin-6 prior to cardiac surgery.

Spiritual struggle appeared consistently to predict poor health outcomes, including mortality. Despite surging interest in the health benefits of religion and spirituality, the health hassle of existential conflicts and proinflammatory cytokines as a potential physiological mechanism has been overlooked. Based on psychological and theological assumptions, we argue for the universal nature of spiritual struggle, a crisis-related existential conflict, and for investigating its physiological influence as essential to understanding human nature. Increased levels of inflammatory cytokines such as interleukin-6 (IL-6) have been linked with adverse health outcomes and negative emotions. This study thus examined spiritual struggle related to plasma IL-6 in 235 adult patients undergoing cardiac surgery, along with positive religious coping, general coping, and optimism, controlling for standardized clinical medical indicators. Multiple regression analysis, following a preplanned sequence, showed that spiritual struggle (p = .011), behavioral coping (p = .013) were positively associated with excess plasma IL-6, controlling for medical correlates (e.g., left ventricular ejection fraction). We conclude that spiritual struggle, indicating the crisis in an existential relation, and behavioral coping strategies are associated with elevated pre-operative plasma IL-6. The interdisciplinary implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessing the effects of bacterial predation on membrane biofouling

Membrane biofouling is one of the major obstacles limiting membrane applications in water treatment. In this study, Bdellovibrio bacteriovorus HD 100, a Gram-negative predatory bacterium, was evaluated as a novel way to mitigate membrane biofouling and its subsequent performance decline. Dead-end microfiltration (MF) tests were carried out on Escherichia coli DH5α and B. bacteriovorus HD 100 co-culture feed solutions. Predation of E. coli was performed at either a low or high multiplicity of infection (MOI), which is defined as the predator to prey cell ratio. The MOIs tested were 2 and 200, and the viability of both the E. coli prey and the predator was monitored over 48 h. The higher MOI (high predator, HP) culture showed a nearly 6-log loss in E. coli number after 24 h when compared to both the control and low MOI (low predator, LP) cultures, whereas the E. coli population within both predated cultures (HP and LP) became nearly identical at 48 h and 4-log lower than that of the control. The unpredated cultures led to significant loss in water flux at 12, 24, and 48 h of culture, but the HP and LP membranes showed less loss of flux by comparison. Analysis of the total membrane resistance showed a similar trend as the flux decline pattern; however, irreversible resistance of the membrane was much higher for the 48 h LP culture compared to the unpredated and HP cultures at 48 h. This increase in irreversible resistance was attributed mainly to E. coli debris, which accumulated in the medium after the predator lysed the prey cells. These results show that pretreatment of wastewater using a suitable concentration of predatory bacteria such as B. bacteriovorus can enhance membrane performance.     

Dielectrophoretically assembled particles: feasibility for optofluidic systems

This work presents the dielectrophoretic manipulation of sub-micron particles suspended in water and the investigation of their optical responses using a microfluidic system. The particles are made of silica and have different diameters of 600, 450, and 250 nm. Experiments show a very interesting feature of the curved microelectrodes, in which the particles are pushed toward or away from the microchannel centerline depending on their levitation heights, which is further analyzed by numerical simulations. In doing so, applying an AC signal of 12 V_p–p and 5 MHz across the microelectrodes along with a flow rate of 1 μl/min within the microchannel leads to the formation of a tunable band of particles along the centerline. Experiments show that the 250 nm particles guide the longitudinal light along the microchannel due to their small scattering. This arrangement is employed to study the feasibility of developing an optofluidic system, which can be potentially used for the formation of particles-core/liquid-cladding optical waveguides.     

Adaptive modelling for adaptive water quality management in the Great Barrier Reef region,Australia

The development and use of a Bayesian Belief Network (BBN) model, within an adaptive management process for the management of water quality in the Mackay Whitsunday region of Queensland, Australia is described. The management goal is firstly to set achievable targets for water quality entering the Great Barrier Reef lagoon from the Mackay Whitsunday natural resource management region and then secondly to define and implement a strategy to achieve these targets. The BBN serves as an adaptive framework that managers and scientists may use to articulate what they know about the managed system. It then provides a tool to guide where, when and what interventions (including research) are most likely to achieve management outcomes. Importantly the BBN provides a platform for collective learning.BBN estimates of total suspended sediment (TSS) loads and event mean concentrations (EMCs) were compared to observed data and results from current best practice models. The BBN estimates were reasonable relative to empirical observations. Example results from the BBN are thereafter used to illustrate the use of the model in estimating the likelihood of exceeding water quality targets with and without proposed actions to improve water quality. Example results are also used to illustrate what spatial or land use elements might contribute most to exceeding water quality targets. Finally key limitations of the tool are discussed and important learnings from the process are highlighted.     

The role of docosahexaenoic acid in retinal function

An important role for docosahexaenoic acid (DHA) within the retina is suggested by its high levels and active conservation in this tissue. Animals raised on n-3-deficient diets have large reductions in retinal DHA levels that are associated with altered retinal function as assessed by the electroretinogram (ERG). Despite two decades of research in this field, little is known about the mechanisms underlying altered retinal function in n-3-deficient animals. The focus of this review is on recent research that has sought to elucidate the role of DHA in retinal function, particularly within the rod photoreceptor outer segments where DHA is found at its highest concentration. An overview is also given of human infant studies that have examined whether a neonatal dietary supply of DHA is required for the normal development of retinal function.