458 research outputs found
Development of Organic Breads and Confectionery
End of project reportIn recent years, concern for the environment and consumer dissatisfaction
with conventional food has led to growing interest in organic farming and
food. The demand has also been fuelled by highly-publicised food scares. Food
safety and genetic modification issues have led some consumers to opt for
organic food as a safer alternative.
Recently, there has been a significant increase in the number of launches of
organic bakery products in Ireland. As a result, there is an increased need to
identify suitable organic bakery ingredients for use in bread and confectionery
formulations. However, only a limited number of scientific studies on the
physical, chemical and functional properties of organic flours and ingredients
exist. The effects of commonly-used ingredients in baking, i.e. organic
improvers and fats, on the baking characteristics of organic products have not
yet been reported and little is known about the influence of approved
additives that may be beneficial to organic baking.
Arising from these gaps in the knowledge base on the use of organic flours and
ingredients, the objective of this study was to evaluate the chemical,
rheological and baking characteristics of white, wholemeal and confectionery
organic flours and to assess the baking potential of organic bakery ingredients,
in particular improvers, fats and additives. Ingredients and baked goods were
compared to non-organic controls.National Development Plan (NDP
Effect of Microstructure on Mechanical Properties of High Strength Steel Weld Metals
The effects of variations in alloying content on the microstructure and mechanical properties of high strength steel weld metals have been studied. Based on neural network modelling, weld metals were produced using shielded metal arc welding with nickel at 7 or 9 wt. %, manganese at 2 or 0.5 wt. % while carbon was varied between 0.03 and 0.11 wt. %. From mechanical testing, it was confirmed that a large gain in impact toughness could be achieved by reducing the manganese content. Carbon additions were found to increase strength with only a minor loss to impact toughness as predicted by the modelling. The highest yield strength (912 MPa) in combination with good impact toughness (over 60 J at –100 oC) was achieved with an alloying content of 7 wt. % nickel, 0.5 wt. % manganese and 0.11 wt. % carbon.
Based on thermodynamic calculations and observed segregation behaviour it was concluded that the weld metals solidify as austenite. The microstructure was characterised using optical, transmission electron and high resolution scanning electron microscopy. At interdendritic regions mainly martensite was found. In dendrite core regions of the low carbon weld metals a mixture of upper bainite, lower bainite and a novel constituent—coalesced bainite—formed. Coalesced bainite was characterised by large bainitic ferrite grains with cementite precipitates and is believed to form when the bainite and martensite start temperatures are close to each other. Carbon additions were found to promote a more martensitic microstructure throughout the dendrites.
Mechanical properties could be rationalised in terms of microstructural constituents and a constitutional diagram was constructed summarising microstructure as a function of manganese and nickel contents
Annual Average Daily Traffic (AADT) Estimation with Regression Using Centrality and Roadway Characteristic Variables
Accurate estimation of annual average daily traffic (AADT) is critical in nearly every roadway decision, such as allocations of funding for roadway improvements and maintenance. While some roadway locations have permanent count stations capable of counting vehicles 24-hours a day throughout the entire year, they are typically only installed at selected locations on major roadways (i.e., freeways and major arterials) with high traffic volumes. On lower functional class roads and roadway segments on higher functional class roads without permanent count stations, short-term coverage counts are collected and adjusted with data from permanent count stations to estimate AADT. Short-term coverage counts are essential because they provide data from roadways of all functional classes and lane configurations, accounting for varying volumes on all roads maintained by an agency. Although necessary, coverage counts can be expensive and can exhaust resources such as investment in data collection workforce, equipment and data analysis. This study develops a strategy for estimating AADT on every roadway within a given jurisdiction using permanent count stations and short term coverage counts, while limiting the number of coverage counts needed. The goal of this thesis is to illustrate a noteworthy time and cost savings using a new centrality based AADT estimation method. A set of new deterministic variables, based on the theory of centrality, are introduced. This study revealed that estimated root mean square error (RMSE) for the new centrality based AADT method is half of the estimated RMSE in the travel demand based AADT model for the same area. Additionally, it was found that using centrality based AADT estimation model, the number of coverage count stations necessary can be reduced by more than 60% compared to the standard factor method for AADT estimation without compromising the AADT estimation accuracy
Generic trending and analysis system
The Generic Trending and Analysis System (GTAS) is a generic spacecraft performance monitoring tool developed by NASA Code 511 and Loral Aerosys. It is designed to facilitate quick anomaly resolution and trend analysis. Traditionally, the job of off-line analysis has been performed using hardware and software systems developed for real-time spacecraft contacts; then, the systems were supplemented with a collection of tools developed by Flight Operations Team (FOT) members. Since the number of upcoming missions is increasing, NASA can no longer afford to operate in this manner. GTAS improves control center productivity and effectiveness because it provides a generic solution across multiple missions. Thus, GTAS eliminates the need for each individual mission to develop duplicate capabilities. It also allows for more sophisticated tools to be developed because it draws resources from several projects. In addition, the GTAS software system incorporates commercial off-the-shelf tools software (COTS) packages and reuses components of other NASA-developed systems wherever possible. GTAS has incorporated lessons learned from previous missions by involving the users early in the development process. GTAS users took a proactive role in requirements analysis, design, development, and testing. Because of user involvement, several special tools were designed and are now being developed. GTAS users expressed considerable interest in facilitating data collection for long term trending and analysis. As a result, GTAS provides easy access to large volumes of processed telemetry data directly in the control center. The GTAS archival and retrieval capabilities are supported by the integration of optical disk technology and a COTS relational database management system
Senior Recital:Anna Keehan, Oboe Tiffany Toennies, Oboe
Kemp Recital Hall Sunday Afternoon October 14, 2007 2:30p.m
Painting and Materiality: Three Creative Strategies for Transformation
This thesis proposes potential material devices to transform the concerns of painting within an expanded field. It suggests that new knowledge is produced in material and subjective relationships. The research began with a propensity towards the subject of drapery and evolved into finding other material conditions that could create a new space for painting. This investigation is conducted through three distinct Creative Strategies, where each one informs methods of thinking for practice. The overarching themes of the individual strategies
are:
Creative Strategy 1: proposes a new theory of prosthetics to transform the physical constraints of painting. I argue that the frame is the crux for expansion and physical transformation. It is achieved through a reductive approach to the physical and material elements of painting within a spatial context.
Creative Strategy 2: explores the material agency of fetish and fabric in making processes and uncovers the underlying fetishistic meaning of the materials associated with my practice.
Creative Strategy 3: reveals the cultural and social significance of drapery in contemporary painting. Significantly, that desire can instigate politicised transformation in painting.
The Creative Strategies provoke a series of linkages between subject and object, which progress through specific analysis on fetishism, femininity, desire and materiality. These explorations advance through the transformative effects of hybridity and multiplicity on expanded painting practices.
Crucially, Estelle Barrett and Barbara Bolt’s concepts concerning material practice and emergent methodologies underpin the practice-led research. Bolt’s idea of a double articulation between practice and theory (2002), is further amplified through the addition of feminist empiricism and feminist autoethnographic methods. These methods are critical lenses in which to examine the research. Moreover, Elizabeth Grosz’ notions on materiality structure the philosophical foundation, which evolved from an initial investigation into Gilles Deleuze’s theories on non-linear thinking. These approaches allow generative and additive
challenges to the construction, assumptions and principal forms of painting.
Through the three Creative Strategies, this PhD delivers a progression of material thinking that will impact upon knowledge around critical modes of enquiry in relation to expanded painting. As an in-depth study of the significance of purposeful tools to enable transformations, the research examines, clarifies and highlights agency in processes and
practices. While significant studies have been carried out on materiality, there are few empirical investigations from within the medium of painting with a focus on drapery and that of an expanded field. Therefore, to summarise, this research contributes to current discourse on material thinking by synthesizing three distinct modes of enquiry, which propose a new approach to contemporary painting
Risks posed by neutron contamination in high energy radiotherapy
Radiotherapy is a common cancer treatment which aims to use radiation energy to kill tumour cells without damaging healthy tissue. High energy x-rays penetrate tissue deeply, depositing most of their energy beyond the skin and shallow tissues. X-rays with energies above 8 MeV may interact to produce neutrons, to which the patient is then exposed. Treatment planning systems (TPS), which calculate the amount of energy deposited to biological structures, do not currently account for contaminant neutrons produced in high energy interactions. Constant improvements in modern radiotherapy techniques have resulted in better patient life expectancy than ever before. The unfortunate corollary of increased life span is increased manifestation of late onset side effects from low dose radiation exposure. This has resulted in an increased drive to reduce the dose to untargeted tissues as much as possible. A perfect treatment plan delivers a prescribed dose to the target volume and no dose to any other tissue. In reality, there is always some tissue through which the radiation must pass in order to reach the target, and some energy which passes beyond the intended target volume. In addition, there is unavoidable scattering of radiation within the patient, which results in out-of-field doses to untargeted tissue. Dose to untargeted tissues resulting from x-ray energy is relatively well understood and is calculated and reported by TPS. Dose resulting from contaminant neutrons is not currently considered by TPS. The overall number of neutrons produced is relatively low, because high energy x-rays may interact in a variety ways and reactions producing neutrons are generally less likely. However, energy deposited by radiation can produce different biological outcomes depending on the type of radiation which deposits the energy. The biological damage inflicted by neutron radiation depends on the energy of the neutrons, and neutrons with energy around 1 MeV may be up to 20 times more damaging than x-rays. So, how do we know the risk associated with neutrons produced from high energy x-rays? Measure the number of neutrons produced? Measure the amount of energy they deposit? Neutron radiation is incredibly difficult to quantify, much more so than alpha, beta, x-ray, gamma or proton radiation. Neutrons are neutrally charged particles, which means they are not attracted or repelled by the positive nuclei or negative electrons which make up all matter. Neutrons primarily pass straight through most materials without leaving a trace of evidence. This makes them quite difficult to detect! Neutrons do interact with the nuclei of some materials, in nuclear reactions, which produce energy and secondary particles which can more easily be detected. The extra energy released in these interactions and their complex probability functions make it difficult to determine the number of neutrons or the energy they would release in human tissue. The high uncertainty in neutron measurement techniques has resulted in some controversy around the use of high energy x-ray beams. There is no question that the deeper penetration of the higher energy x-rays is extremely useful for treatment of some anatomical sites. The source of the contention is the degree of risk posed by the neutrons themselves. Without an accurate and precise method for quantifying the degree of neutron contamination, an accurate determination of the risk cannot be made. Thermoluminescence dosimeters (TLDs) and activation foils have been used in this work to quantify neutrons produced in high energy radiotherapy. TLDs are a common radiotherapy dose measurement tool and are routinely used in existing clinical protocols. Lithium fluoride is a common TLD material and the two naturally occurring isotopes of lithium, 6Li and 7Li, have very different probabilities for neutron interaction. TLDs made from these materials can be used in pairs to produce signals which in combination can be correlated with the degree of neutron exposure. Activation foils are materials which become radioactive when exposed to neutrons. A first principles calculation can be used to determine the number of neutrons causing activation in a material. Both these methods for neutron detection are highly dependent on the energy of the neutrons. Both produce a response related to the number of incident neutrons which needs to be corrected for the energy of the neutrons which are to be measured. The energy deposited by the neutrons in the detector material is not directly related to the energy which would be deposited in tissue in a patient exposure. Another energy correction is required to quantify the biological damage which may occur. This is the primary source of uncertainty and the cause of the disagreement between the vast number of existing publications on the topic. This work determines energy correction values for the calibration of LiF TLDs for neutron measurements. The neutron energy spectrum relevant to high energy radiotherapy is modelled and used to determine energy corrections for activation foils. It is also needed to convert the response of detectors to the energy deposition in tissue and to correct for biological effect. Additional risk from neutron contamination is also examined. The production of neutrons may induce radioactivity in other materials. The medical linear accelerator (linac) used to produce the treatment x-rays may itself become radioactive when it is operated at high energies. The induced activity is low level and is mainly of concern for radiotherapy staff rather than patients as they spend much greater time in proximity to the linac. Implants within the patient may also interact in unexpected ways. Metallic implants such as prosthetic hips can become radioactive from exposure to neutrons or high energy x-rays. This is primarily of concern for patients, as it potentially induces a low level internal source of radiation. Many existing peer reviewed publications investigate the degree of neutron exposure to patients undergoing high energy radiotherapy, but there is no consensus amongst experts regarding the risk. This stems from the high degree of uncertainty in neutron measurement techniques. This thesis discusses the challenges of neutron dosimetry and proposes a methodology for correcting for detector energy dependence. An investigation of the indirect risks of neutron production is also presented. This thesis offers a comprehensive analysis of existing neutron detectors and dosimeters with an in-depth discussion of their properties in relation to their suitability for use in high energy radiotherapy. The energy dependence of LiF TLD response to neutron radiation is carefully examined for calibration sources and for photoneutrons from medical linacs. The energy dependence should be considered for calibration sources, but is shown to be less critical for the energies produced by linacs. The energy dependence of activation foils depends on the material chosen but can be accounted for by calculating an energy spectrum weighted interaction probability, or cross section. Converting neutron measurements to values representing dose to human tissue for a given exposure must be corrected for the energy of the neutrons. This thesis also presents a summary of neutron dose equivalent values from peer reviewed publications and compares the effects of a number of parameters on the neutron dose. Comparison between studies is made difficult by a lack of detail on the magnitude of energy corrections used in published papers. The indirect risk from secondary activations is considerably lower, however may be reduced by employing the existing collimation devices within linacs as shielding. A small amount of activation in hip prostheses does occur, but does not result in a significant dose to surrounding tissue
A frameshift-deletion mutation in Reelin causes cerebellar hypoplasia in White Swiss Shepherd dogs.
Cerebellar hypoplasia is a heterogeneous neurological condition in which the cerebellum is smaller than usual or not completely developed. The condition can have genetic origins, with Mendelian-effect mutations described in several mammalian species. Here, we describe a genetic investigation of cerebellar hypoplasia in White Swiss Shepherd dogs, where two affected puppies were identified from a litter with a recent common ancestor on both sides of their pedigree. Whole genome sequencing was conducted for 10 dogs in this family, and filtering of these data based on a recessive transmission hypothesis highlighted five protein-altering candidate variants - including a frameshift-deletion of the Reelin (RELN) gene (p.Val947*). Given the status of RELN as a gene responsible for cerebellar hypoplasia in humans, sheep and mice, these data strongly suggest the loss-of-function variant as underlying these effects. This variant has not been found in other dog breeds nor in a cohort of European White Swiss Shepherds, suggesting a recent mutation event. This finding will support the genotyping of a more diverse sample of dogs, and should aid future management of the harmful allele through optimised mating schemes
Illustrating potential efficiency gains from using cost-effectiveness evidence to reallocate Medicare expenditures
This article is available open access through the publisher’s website at the linke below. Copyright @ 2013, International Society for Pharmacoeconomics and
Outcomes Research (ISPOR).This article has been made available through the Brunel Open Access Publishing Fund.Objectives - The Centers for Medicare & Medicaid Services does not explicitly use cost-effectiveness information in national coverage determinations. The objective of this study was to illustrate potential efficiency gains from reallocating Medicare expenditures by using cost-effectiveness information, and the consequences for health gains among Medicare beneficiaries.
Methods - We included national coverage determinations from 1999 through 2007. Estimates of cost-effectiveness were identified through a literature review. For coverage decisions with an associated cost-effectiveness estimate, we estimated utilization and size of the “unserved” eligible population by using a Medicare claims database (2007) and diagnostic and reimbursement codes. Technology costs originated from the cost-effectiveness literature or were estimated by using reimbursement codes. We illustrated potential aggregate health gains from increasing utilization of dominant interventions (i.e., cost saving and health increasing) and from reallocating expenditures by decreasing investment in cost-ineffective interventions and increasing investment in relatively cost-effective interventions.
Results - Complete information was available for 36 interventions. Increasing investment in dominant interventions alone led to an increase of 270,000 quality-adjusted life-years (QALYs) and savings of $12.9 billion. Reallocation of a broader array of interventions yielded an additional 1.8 million QALYs, approximately 0.17 QALYs per affected Medicare beneficiary. Compared with the distribution of resources prior to reallocation, following reallocation a greater proportion was directed to oncology, diagnostic imaging/tests, and the most prevalent diseases. A smaller proportion of resources went to cardiology, treatments (including drugs, surgeries, and medical devices, as opposed to nontreatments such as preventive services), and the least prevalent diseases.
Conclusions - Using cost-effectiveness information has the potential to increase the aggregate health of Medicare beneficiaries while maintaining existing spending levels.The Commonwealth Fun
Development of Query Strategies to Identify a Histologic Lymphoma Subtype in a Large Linked Database System
Background: Large linked databases (LLDB) represent a novel resource for cancer outcomes research. However, accurate means of identifying a patient population of interest within these LLDBs can be challenging. Our research group developed a fully integrated platform that provides a means of combining independent legacy databases into a single cancer-focused LLDB system. We compared the sensitivity and specifi city of several SQL-based query strategies for identifying a histologic lymphoma subtype in this LLDB to determine the most accurate legacy data source for identifying a specifi c cancer patient population.Methods: Query strategies were developed to identify patients with follicular lymphoma from a LLDB of cancer registry data, electronic medical records (EMR), laboratory, administrative, pharmacy, and other clinical data. Queries were performed using common diagnostic codes (ICD-9), cancer registry histology codes (ICD-O), and text searches of EMRs. We reviewed medical records and pathology reports to confirm each diagnosis and calculated the sensitivity and specificity for each query strategy.Results: Together the queries identified 1538 potential cases of follicular lymphoma. Review of pathology and other medical reports confirmed 415 cases of follicular lymphoma, 300 pathology-verifi ed and 115 verified from other medical reports. The query using ICD-O codes was highly specific (96%). Queries using text strings varied in sensitivity (range 7–92%) and specifi city (range 86–99%). Queries using ICD-9 codes were both less sensitive (34–44%) and specific (35–87%).Conclusions: Queries of linked-cancer databases that include cancer registry data should utilize ICD-O codes or employ structured free-text searches to identify patient populations with a precise histologic diagnosis.Abbreviations: LLDB: Large Linked Database; SEER: Surveillance Epidemiology and End Results; EMR: Electronic Medical Record; ICD-9: International Classifi cation of Diseases (9th revision); ICD-O: International Classifi cation of Diseases for Oncology; AP: Anatomical Pathology; WHO: World Health Organization
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