Measurement of substrate thermal resistance using DNA denaturation temperature

Heat Transfer and Thermal Management have become important aspects of the developing field of uTAS systems particularly in the application of the the uTAS philosophy to thermally driven analysis techniques such as PCR. Due to the development of flowing PCR thermocyclers in the field of uTAS, the authors have previously developed a melting curve analysis technique that is compatible with these flowing PCR thermocyclers. In this approach a linear temperature gradient is induced along a sample carrying microchannel. Any flow passing through the microchannel is subject to linear heating. Fluorescent monitoring of DNA in the flow results in the generation of DNA melting curve plots. This works presents an experimental technique where DNA melting curve analysis is used to measure the thermal resistance of microchannel substrates. DNA in solution is tested at a number of different ramp rates and the di®erent apparent denaturation temperatures measured are used to infer the thermal resistance of the microchannel substrates. The apparent variation in denaturation temperature is found to be linearly proportional to flow ramp rate. Providing knowledge of the microchannel diameter and a non-varying cross-section in the direction of heat flux the thermal resistance measurement technique is independent of knowledge of substrate dimensions, contact surface quality and substrate composition/material properties. In this approach to microchannel DNA melting curve analysis the difference between the measured and actual denaturation temperatures is proportional to the substrate thermal resistance and the ramp-rate seen by the sample. Therefore quantitative knowledge of the substrate thermal resistance is required when using this technique to measure accurately DNA denaturation temperatur

Exhibition Layout and Visitor Movement in Science Museums

Two arguments are made based on the analysis of traveling science exhibitions. First, sufficiently refined techniques of spatial analysis allow us to identify the impact of layout upon visitors' paths and behaviors even in moderately sized open plans which afford almost random sequences of movement and relatively unobstructed visibility. Specifically, contact with exhibits is associated with their relative accessibility while active engagement is associated with exhibit cross-visibility. Second, newly developed or adapted techniques of analysis allow us to make a transition from modeling the mechanics of spatial movement (the way in which movement is affected by the distribution of obstacles and boundaries) to modeling the manner in which movement registers additional aspects of visual information, particularly the arrangement of exhibits according to conceptual organizing themes. The advantages of such purely spatial modes of analysis extend into providing us with a sharper understanding of some of the underlying constraints within which exhibition content is conceived and designed

ICNMM2008-62014 Microchannel Fluorescent Melting Curve Analysis

ABSTRACT I

Fifth-grade students’ digital retellings and the Common Core: Modal use and design intentionality

Multimodal composing is part of the Common Core vision of the twenty-first-century student. Two descriptive studies were conducted of fifth-grade students’ digital folktale retellings. Study 1 analyzed 83 retellings in relation to the types and frequencies of modal use, such as image, sound, movement, and written text, as well as their retelling accuracy. Students composed within a scaffolded digital composing environment which comprised the PowerPoint authoring/presentation tool and a researcher-developed story frame. All students’ retellings included writing and visual design, 80% included animation, and 70% included sound. Retelling accuracy scores averaged 54%. Study 2 was conducted with a new group of 14 fifth-grade students who had previous digital retelling experience. The retellings included the same types of modal use, but at a higher level of frequency. In their retrospective design interviews, students expressed design intentionality and a metamodal awareness of how modes work together to create an appealing story

Using positive behavioural support as a treatment for trauma symptoms with a man with intellectual disabilities

Background. There is robust evidence that psychological therapies are an effective treatment for trauma-related symptoms, including post-traumatic stress disorder. However, there are relatively few studies involving people with intellectual disabilities, and no studies drawing on positive behavioural support as the mechanism for the delivery of treatment. Method and materials. This study was a descriptive case report of a young man with intellectual disabilities who had a history of early trauma. His challenging behaviour was associated with demand avoidance. A positive behavioural support plan, incorporating psychological therapies and medication, was developed, implemented and is described. Results. Over time, challenging behaviours reduced and were eventually extinguished. This was associated with an increase in engagement in a variety of activities and a reduction in trauma-related symptoms. Discussion. Using positive behaviour support plans as the organisational framework for the adaptation and delivery of both psychological therapies and medication for complex cases is advantageous. Excellent team working is necessary to ensure that interventions are successful

Integrated methodologies of economics and socio-economics assessments in ocean renewable energy : private and public perspectives

This paper offers a holistic approach to the evaluation of an ocean renewable energy (ORE) technology type or specific project in order to provide a comprehensive assessment of both narrow economic and broader socio-economic performance. This assessment incorporates methods from three pillars areas: Economic - financial returns and efficient use of resources, Social - employment, social and community cohesion and identity, and Environmental - including the physical environment and pollution. These three pillars are then considered in the broader context of governance. In order to structure this evaluation, a novel parameter space model was created, defined by the three pillars and by the scale of the system under assessment. The scale of the system ranged from individual components of an ORE project; to projects comprising of a number of devices; through to a geographic regions in which multiple farms may be deployed. The parameter space consists of an inner circle representing the boundary of interest for a private investor, or a firm, developing an ORE project. The outer circle is characterised by assessment tools typically employed at the broader stakeholder level including economic, social, and environmental methods that can be employed at local, regional or national scale and which are typically employed to inform policy and decision making regarding ORE. Governance sets the stage within which management occurs. Wider impacts to the firm undertaking the project will take into account “externalities” of the project across the three fields. In this model, key methods identified are mapped onto this parameter space and the connectivity explored. The paper demonstrates that the three pillars are inter-connected and each must be considered in any meaningful assessment of ORE sustainability. An integrated assessment approach has the ability to address both the private and the public aspects of an ORE development,. This analysis provides insights on existing best practice, but also reveals the potential for disconnect between an ORE project’s commercial viability and its contribution to environmental and social goals

Effect of substrate thermal resistance on space-domain microchannel

In recent years, Fluorescent Melting Curve Analysis (FMCA) has become an almost ubiquitous feature of commercial quantitative PCR (qPCR) thermal cyclers. Here a micro-fluidic device is presented capable of performing FMCA within a microchannel. The device consists of modular thermally conductive blocks which can sandwich a microfluidic substrate. Opposing ends of the blocks are held at differing temperatures and a linear thermal gradient is generated along the microfluidic channel. Fluorescent measurements taken from a sample as it passes along the micro-fluidic channel permits fluorescent melting curves to be generated. In this study we measure DNA melting temperature from two plasmid fragments. The effects of flow velocity and ramp-rate are investigated, and measured melting curves are compared to those acquired from a commercially available PCR thermocycler

Next generation PCR microfluidic system

Stokes Bio, founded in 2005, develops innovative microfluidic technologies. In 2008 in collaboration with Monsanto, an application driven development for a high-throughput instrument in the detection and characterisation of Single Nucleotide Polymorphisms (SNPs) in agricultural crops was initiated. Stokes technology is designed to generate aqueous nanolitre scale droplets of reagents and samples, wrapped in a carrier fluid from standard microtitre plates and to mix them using Stokes Bio’s proprietary liquid bridge mixers. Following mixing the complete assay is transferred in the carrier fluid through the use of a continuous flow system, to a flow through thermal cycler and an optical reading station. This poster summarises results collated using the Stokes Bio genotyping platform currently based in Monsanto. Data will be presented to illustrate the dynamic capabilities of the instrument, highlighting the enhanced sensitivity and reproducibility of PCR in droplet format compared to well-based technologies

Smoking in film in New Zealand: measuring risk exposure

BACKGROUND: Smoking in film is a risk factor for smoking uptake in adolescence. This study aimed to quantify exposure to smoking in film received by New Zealand audiences, and evaluate potential interventions to reduce the quantity and impact of this exposure. METHODS: The ten highest-grossing films in New Zealand for 2003 were each analysed independently by two viewers for smoking, smoking references and related imagery. Potential interventions were explored by reviewing relevant New Zealand legislation, and scientific literature. RESULTS: Seven of the ten films contained at least one tobacco reference, similar to larger film samples. The majority of the 38 tobacco references involved characters smoking, most of whom were male. Smoking was associated with positive character traits, notably rebellion (which may appeal to adolescents). There appeared to be a low threshold for including smoking in film. Legislative or censorship approaches to smoking in film are currently unlikely to succeed. Anti-smoking advertising before films has promise, but experimental research is required to demonstrate cost effectiveness. CONCLUSION: Smoking in film warrants concern from public health advocates. In New Zealand, pre-film anti-smoking advertising appears to be the most promising immediate policy response

First Isolation of Hepatitis E Virus Genotype 4 in Europe through Swine Surveillance in the Netherlands and Belgium

Hepatitis E virus (HEV) genotypes 3 and 4 are a cause of human hepatitis and swine are considered the main reservoir. To study the HEV prevalence and characterize circulating HEV strains, fecal samples from swine in the Netherlands and Belgium were tested by RT-PCR. HEV prevalence in swine was 7–15%. The Dutch strains were characterized as genotype 3, subgroups 3a, 3c and 3f, closely related to sequences found in humans and swine earlier. The HEV strains found in Belgium belonged to genotypes 3f and 4b. The HEV genotype 4 strain was the first ever reported in swine in Europe and an experimental infection in pigs was performed to isolate the virus. The genotype 4 strain readily infected piglets and caused fever and virus shedding. Since HEV4 infections have been reported to run a more severe clinical course in humans this observation may have public health implications