Blue bottle light: lecture demonstrations of homogeneous and heterogeneous photo-induced electron transfer reactions

The classic, non-photochemical blue bottle experiment involves the reaction of methylene blue (MB) with deprotonated glucose, to form a bleached form of the dye, leuco-methylene blue (LMB), and subsequent colour recovery by shaking with air. This reaction is a popular demonstrator of key principles in kinetics and reaction mechanisms. Here it is modified so as to highlight features of homogenous and heterogeneous photoinduced electron transfer (PET) (Pure Appl. Chem., 2007, 79, 293-465) reactions, i.e. blue bottle light experiments. The homogeneous blue bottle light experiment uses methylene blue, MB, as the photo-sensitizer and triethanolamine as the sacrificial electron donor. Visible light irradiation of this system leads to its rapid bleaching, followed by the ready restoration of its original colour upon shaking away from the light source. The heterogeneous blue bottle light experiment uses titania as the photo-sensitizer, MB as a redox indicator and glucose as the sacrificial electron donor. UVA light irradiation of this system leads to the rapid bleaching of the MB and the gradual restoration of its original colour with shaking and standing. The latter 'dark' step can be made facile and more demonstrator-friendly by using platinised titania particles. These two photochemical versions of the blue bottle experiment are used to explore the factors which underpin homogeneous and heterogeneous PET reactions and provide useful demonstrations of homogeneous and heterogeneous photochemistry.

Design of a deployment rotation mechanism for microsatellite

Solar array rotation mechanism provides a hinged joint between the solar panel and satellite body, smooth rota-tion of the solar array into deployed position and its fixation in this position. After unlocking of solar panel (while in orbit), rotation bracket turns towards ready-to-work position under the action of driving spring. During deployment, once reached the required operating angle (defined by power subsystem engineer), the rotation bracket collides with the fixed bracket that is mounted on body of the satellite, to stop rotation. Due to the effect of collision force that may alter the rotation mechanism function, design of centrifugal brake is essential. At stoppage moment micro-switches activate final position sensor and a stopper locks the rotation bracket. Design of spring and centrifugal brake components, static finite element stress analysis of primary structure body of rotation mechanism at stoppage moment have been obtained. Last, reliability analysis of rotation mechanism is evaluated. The benefit of this study is to aid in the design of rotation mechanism that can be used in micro-satellite applications.

DESIGN, ANALYSIS, AND RELIABILTY OF SOLAR PANEL ROTATION MECHANISM FOR MICROSATELLITE

Solar array rotation mechanism provides a hinged joint between the solar panel and satellite body, smooth rotation of the solar array into deployed position and its fixation in this position. After unlocking of solar panel (while in orbit), rotation bracket turns towards ready-to-work position under the action of driving spring. During deployment, once reached the required operating angle (defined by power subsystem engineer), the rotation bracket collides with the fixed bracket that is mounted on body of the satellite, to stop rotation. Due to the effect of collision force that may alter the rotation mechanism function, design of centrifugal brake is essential. At stoppage moment micro-switches activate final position sensor and a stopper locks the rotation bracket. Design of spring and centrifugal brake components, static finite element stress analysis of primary structure body of rotation mechanism at stoppage moment have been obtained. Last, reliability analysis of rotation mechanism is evaluated. The benefit of this study is to aid in the design of rotation mechanism that can be used in micro-satellite applications.

Behavioural consequences of imagining intergroup contact with stigmatized outgroups

We investigated whether imagining contact with an outgroup member would change intergroup behaviour. Participants who had imagined a positive interaction with an outgroup member or an unspecified stranger were told that they were about to take part in a discussion task with an outgroup member. They were taken to a room and asked to set out two chairs ready for the discussion while the experimenter left, ostensibly to find the other participant. The distance between the two chairs was then measured. Undergraduate students who imagined talking to an obese individual (Experiment 1) or a Muslim individual (Experiment 2) placed the chairs significantly closer than those in the control condition. They also reported more positive feelings and beliefs regarding Muslims. These findings highlight an important practical application of imagined contact: preparing people for successful face-to-face contact.

Arsenic accumulation and metabolism in rice (Oryza sativa L.)

The use of arsenic (As) contaminated groundwater for irrigation of crops has resulted in elevated concentrations of arsenic in agricultural soils in Bangladesh, West Bengal (India), and elsewhere. Paddy rice (Oryza sativa L.) is the main agricultural crop grown in the arsenic-affected areas of Bangladesh. There is, therefore, concern regarding accumulation of arsenic in rice grown those soils. A greenhouse study was conducted to examine the effects of arsenic-contaminated irrigation water on the growth of rice and uptake and speciation of arsenic. Treatments of the greenhouse experiment consisted of two phosphate doses and seven different arsenate concentrations ranging from 0 to 8 mg of As L(-1) applied regularly throughout the 170-day post-transplantation growing period until plants were ready for harvesting. Increasing the concentration of arsenate in irrigation water significantly decreased plant height, grain yield, the number of filled grains, grain weight, and root biomass, while the arsenic concentrations in root, straw, and rice husk increased significantly. Concentrations of arsenic in rice grain did not exceed the food hygiene concentration limit (1.0 mg of As kg(-1) dry weight). The concentrations of arsenic in rice straw (up to 91.8 mg kg(-1) for the highest As treatment) were of the same order of magnitude as root arsenic concentrations (up to 107.5 mg kg(-1)), suggesting that arsenic can be readily translocated to the shoot. While not covered by food hygiene regulations, rice straw is used as cattle feed in many countries including Bangladesh. The high arsenic concentrations may have the potential for adverse health effects on the cattle and an increase of arsenic exposure in humans via the plant-animal-human pathway. Arsenic concentrations in rice plant parts except husk were not affected by application of phosphate. As the concentration of arsenic in the rice grain was low, arsenic speciation was performed only on rice straw to predict the risk associated with feeding contaminated straw to the cattle. Speciation of arsenic in tissues (using HPLC-ICP-MS) revealed that the predominant species present in straw was arsenate followed by arsenite and dimethylarsinic acid (DMAA). As DMAA is only present at low concentrations, it is unlikely this will greatly alter the toxicity of arsenic present in rice.

Determining the regional potential for a grass biomethane industry

Grass biogas/biomethane has been put forward as a renewable energy solution and it has been shown to perform well in terms of energy balance, greenhouse gas emissions and policy constraints. Biofuel and energy crop solutions are country-specific and grass biomethane has strong potential in countries with temperate climates and a high proportion of grassland, such as Ireland. For a grass biomethane industry to develop in a country, suitable regions (i.e. those with the highest potential) must be identified. In this paper, factors specifically related to the assessment of the potential of a grass biogas/biomethane industry are identified and analysed. The potential for grass biogas and grass biomethane is determined on a county-by-county basis using multi-criteria decision analysis. Values are assigned to each county and ratings and weightings applied to determine the overall county potential. The potential for grass biomethane with co-digestion of slaughter waste (belly grass) is also determined. The county with the highest potential (Limerick) is analysed in detail and is shown to have ready potential for production of gaseous biofuel to meet either 50% of the vehicle fleet or 130% of the domestic natural gas demand, through 25 facilities at a scale of ca. 30ktyr of feedstock. The assessment factors developed in this paper can be used in other resource studies into grass biomethane or other energy crops. © 2010 Elsevier Ltd.

A Unified Scheduler for Recursive and Task Dataflow Parallelism

Task dataflow languages simplify the specification of parallel programs by dynamically detecting and enforcing dependencies between tasks. These languages are, however, often restricted to a single level of parallelism. This language design is reflected in the runtime system, where a master thread explicitly generates a task graph and worker threads execute ready tasks and wake-up their dependents. Such an approach is incompatible with state-of-the-art schedulers such as the Cilk scheduler, that minimize the creation of idle tasks (work-first principle) and place all task creation and scheduling off the critical path. This paper proposes an extension to the Cilk scheduler in order to reconcile task dependencies with the work-first principle. We discuss the impact of task dependencies on the properties of the Cilk scheduler. Furthermore, we propose a low-overhead ticket-based technique for dependency tracking and enforcement at the object level. Our scheduler also supports renaming of objects in order to increase task-level parallelism. Renaming is implemented using versioned objects, a new type of hyper object. Experimental evaluation shows that the unified scheduler is as efficient as the Cilk scheduler when tasks have no dependencies. Moreover, the unified scheduler is more efficient than SMPSS, a particular implementation of a task dataflow language.

Pre-storage of gelified reagents in a lab-on-a-foil system for rapid nucleic acid analysis

Reagent pre-storage in a microfluidic chip can enhance operator convenience, simplify the system design, reduce the cost of storage and shipment, and avoid the risk of cross-contamination. Although dry reagents have long been used in lateral flow immunoassays, they have rarely been used for nucleic acid-based point-of-care (POC) assays due to the lack of reliable techniques to dehydrate and store fragile molecules involved in the reaction. In this study, we describe a simple and efficient method for prolonged on-chip storage of PCR reagents. The method is based on gelification of all reagents required for PCR as a ready-to-use product. The approach was successfully implemented in a lab-on-a-foil system, and the gelification process was automated for mass production. Integration of reagents on-chip by gelification greatly facilitated the development of easy-to-use lab-on-a-chip (LOC) devices for fast and cost-effective POC analysis.

GELIFICATION - A SIMPLE AND EFFICIENT METHOD FOR ON-CHIP STORAGE OF REAGENTS: TOWARDS LAB-ON-A-CHIP SYSTEMS FOR POINT-OF-CARE DIAGNOSTICS

In this study, we describe a simple and efficient method for on-chip storage of reagents for point-of-care (POC) diagnostics. The method is based on gelification of all reagents required for on-chip PCR-based diagnostics as a ready-to-use product. The result reported here is a key step towards the development of a ready and easy to use fully integrated Lab-on-a-chip (LOC) system for fast, cost-effective and efficient POC diagnostics analysis.

Protocolized versus non-protocolized weaning for reducing the duration of invasive mechanical ventilation in critically ill paediatric patients

Background:Mechanical ventilation is a critical component of paediatric intensive care therapy. It is indicated when the patient’s spontaneous ventilation is inadequate to sustain life. Weaning is the gradual reduction of ventilatory support and the transfer of respiratory control back to the patient. Weaning may represent a large proportion of the ventilatory period. Prolonged ventilation is associated with significant morbidity, hospital cost, psychosocial and physical risks to the child and even death. Timely and effective weaning may reduce the duration of mechanical ventilation and may reduce the morbidity and mortality associated with prolonged ventilation. However, no consensus has been reached on criteria that can be used to identify when patients are ready to wean or the best way to achieve it.Objectives:To assess the effects of weaning by protocol on invasively ventilated critically ill children. To compare the total duration of invasive mechanical ventilation of critically ill children who are weaned using protocols versus those weaned through usual (non-protocolized) practice. To ascertain any differences between protocolized weaning and usual care in terms of mortality, adverse events, intensive care unit length of stay and quality of life.Search methods:We searched the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library, Issue 10, 2012), MEDLINE (1966 to October 2012), EMBASE (1988 to October 2012), CINAHL (1982 to October 2012), ISI Web of Science and LILACS. We identified unpublished data in the Web of Science (1990 to October 2012), ISI Conference Proceedings (1990 to October 2012) and Cambridge Scientific Abstracts (earliest to October 2012). We contacted first authors of studies included in the review to obtain further information on unpublished studies or work in progress. We searched reference lists of all identified studies and review papers for further relevant studies. We applied no language or publication restrictions.Selection criteriaWe included randomized controlled trials comparing protocolized weaning (professional-led or computer-driven) versus non-protocolized weaning practice conducted in children older than 28 days and younger than 18 years.Data collection and analysis:Two review authors independently scanned titles and abstracts identified by electronic searching. Three review authors retrieved and evaluated full-text versions of potentially relevant studies, independently extracted data and assessed risk of bias.Main results:We included three trials at low risk of bias with 321 children in the analysis. Protocolized weaning significantly reduced total ventilation time in the largest trial (260 children) by a mean of 32 hours (95% confidence interval (CI) 8 to 56; P = 0.01). Two other trials (30 and 31 children, respectively) reported non-significant reductions with a mean difference of -88 hours (95% CI -228 to 52; P = 0.2) and -24 hours (95% CI -10 to 58; P = 0.06). Protocolized weaning significantly reduced weaning time in these two smaller trials for a mean reduction of 106 hours (95% CI 28 to 184; P = 0.007) and 21 hours (95% CI 9 to 32; P < 0.001). These studies reported no significant effects for duration of mechanical ventilation before weaning, paediatric intensive care unit (PICU) and hospital length of stay, PICU mortality or adverse events.Authors' conclusions:Limited evidence suggests that weaning protocols reduce the duration of mechanical ventilation, but evidence is inadequate to show whether the achievement of shorter ventilation by protocolized weaning causes children benefit or harm.

Suspected giant cell arteritis:A study of referrals for temporal artery biopsy

Background: The purpose of this study is to describe the nature of cases undergoing temporal artery biopsy (TAB) for suspected giant cell arteritis (GCA). Methods: A retrospective review of case notes was undertaken for all patients on whom ophthalmologists had performed TAB in 2 teaching hospitals between 1995 and 2001. Presenting symptoms, referring specialty, TAB result, treatment, and discharge diagnosis were recorded. Results: Ophthalmologists performed TAB on 110 patients for suspected GCA. A variety of specialties referred patients to ophthalmology for TAB; presenting symptoms varied with referral source. Of the 110 TABs, 21 (19%) were reported as positive for GCA, 84 (76%) were negative, and 5 (4.5%) were reported as inadequate. The symptoms most commonly associated with a positive TAB were visual disturbance (15/21) and headache (15/21).The odds ratios for having a positive TAB result rather than a negative result were 1.0 for the presence of headache, 4.1 for visual disturbance, and 6.7 for jaw claudication. Interpretation: Physicians were faced with a different population of GCA suspects than ophthalmologists. While physicians should be alert to the significance of visual symptoms or jaw claudication, ophthalmologists should be ready to facilitate prompt TABs when appropriate. TAB should be performed promptly and an adequate length of artery taken for biopsy. An argument can be made that TAB is not needed in cases of suspected GCA. However, a positive result provides firm justification for the use of steroids. We feel that TAB has a useful role and we make reference to methods to maximize its usefulness.

Universal tight binding model for chemical reactions in solution and at surfaces. I. Organic molecules

As is now well established, a first order expansion of the Hohenberg-Kohn total energy density functional about a trial input density, namely, the Harris-Foulkes functional, can be used to rationalize a non self consistent tight binding model. If the expansion is taken to second order then the energy and electron density matrix need to be calculated self consistently and from this functional one can derive a charge self consistent tight binding theory. In this paper we have used this to describe a polarizable ion tight binding model which has the benefit of treating charge transfer in point multipoles. This admits a ready description of ionic polarizability and crystal field splitting. It is necessary in constructing such a model to find a number of parameters that mimic their more exact counterparts in the density functional theory. We describe in detail how this is done using a combination of intuition, exact analytical fitting, and a genetic optimization algorithm. Having obtained model parameters we show that this constitutes a transferable scheme that can be applied rather universally to small and medium sized organic molecules. We have shown that the model gives a good account of static structural and dynamic vibrational properties of a library of molecules, and finally we demonstrate the model's capability by showing a real time simulation of an enolization reaction in aqueous solution. In two subsequent papers, we show that the model is a great deal more general in that it will describe solvents and solid substrates and that therefore we have created a self consistent quantum mechanical scheme that may be applied to simulations in heterogeneous catalysis.

Elements of A New Framework for the principle of Equal Treatment of persons in EC Law

In June and November 2000, the European Parliament and the Council adopted two Directives referring to ‘the principle of equal treatment irrespective of’ in their title, one relating to racial and ethnic origin, the other to disability, age, religion and belief or sexual orientation. A thorough reform of Directive 76/207/EEC on the principle of equal treatment for women and men in employment matters is pending between the European Parliament's second reading and adoption while this is written. Community secondary legislation on equal treatment of persons has thus expanded in scope and number of reasons which must not serve as starting points for differentiation. Does this signify progress in legal protection against personal discrimination? While not providing a ready answer, this article proposes an analytical framework to answer this question, concentrating on conceptions of equality in general and in particular on the problems multi-dimensional discrimination might pose for the law.

Cases, Materials and Text on National, Supranational and International Non-Discrimination Law

This casebook, the result of the collaborative efforts of a panel of experts from various EU Member States, is the latest in the Ius Commune Casebook series developed at the Universities of Maastricht and Leuven. The book provides a comprehensive and skilfully designed resource for students, practitioners, researchers, public officials, NGOs, consumer organisations and the judiciary. In common with earlier books in the series, this casebook presents cases and other materials (legislative materials, international and European materials, excerpts from books or articles). As non-discrimination law is a comparatively new subject, the chapters search for and develop the concepts of discrimination law on the basis of a wide variety of young and often still emerging case law and legislation. The result is a comprehensive textbook with materials from a wide variety of EU Member States. The book is entirely in English (i.e. materials are translated where not available in English). At the end of each chapter a comparative overview ties the material together, with emphasis, where appropriate, on existing or emerging general principles in the legal systems within Europe.
The book illustrates the distinct relationship between international, European and national legislation in the field of non-discrimination law. It covers the grounds of discrimination addressed in the Racial Equality and Employment Equality Directives, as well as non-discrimination law relating to gender. In so doing, it covers the law of a large number of EU Member States, alongside some international comparisons.
The Ius Commune Casebook on Non-Discrimination Law
- provides practitioners with ready access to primary and secondary legal material needed to assist them in crafting test case strategies.
- provides the judiciary with the tools needed to respond sensitively to such cases.
- provides material for teaching non-discrimination law to law and other students.
- provides a basis for ongoing research on non-discrimination law.
- provides an up-to-date overview of the implementation of the Directives and of the state of the law.
This Casebook is the result of a project which has been supported by a grant from the European Commission's Anti-Discrimination Programme.

Deliberative Perfectionism: Why We Can and Should Talk about the Good

In contemporary political theory, perfectionists believe that the state should promote substantive conceptions of the good through its legislation. Supporters of neutrality, instead, claim that the state should refrain from doing so. In this article I analyse perfectionism in relation to Jürgen Habermas’ theory of discourse and deliberative politics (1996) and critique Habermas’ distinction between ‘ethical’ and ‘moral’ discourses (1984, 1990). By relating Habermas’ theory to George Sher’s account of perfectionism (1997), I argue that we can establish the meta-ethical grounds for a model of deliberation encompassing ethical matters (that is, questions concerning the good life) not confined to the limits of specific communities. I conclude by arguing that ethical deliberation is not only feasible but also desirable. Given the fact of ethical pluralism, and in order to show respect towards their fellow citizens, political perfectionists ought to be ready to show how their ethical claims (which they want to see translated into state policy) relate to deeper meta-ethical human goals on which we can ideally find a consensus through deliberation.