1,028 research outputs found

    Testing for the Internal Consistency of Choice Experiments Using Explicit Rankings of Quality Attributes

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    Choice experiments (CEs) are an increasingly important tool in the environmental valuation literature because of their ability to deal with multifaceted environmental issues and their basis in random utility theory. One particularly useful aspect of the CE method is that it allows researchers to estimate marginal rates of substitution between an environmental resource’s various attributes. These marginal rates of substitution provide an implicit ranking of the attributes, which can be compared with other ranking mechanisms. In this paper we describe a method for testing for the internal consistency of choice experiments by comparing the implicit attribute ranking generated by a CE with that generated by an explicit attribute-ranking exercise. The analysis uses data gathered through a unique survey in which respondents completed both a CE exercise and an attribute-ranking exercise indicating their preferences over pollution abatement and water quality improvement strategies for a freshwater lake in north-central Iowa. Comparisons are made on a sample-wide basis as well as an individual basis.Environmental valuation, choice experiments, internal consistency

    Neoarchean Mantle-derived Magmatism within the Repulse Bay Block, Melville Peninsula, Nunavut: Implications for Archean Crustal Extraction and Cratonization

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    SUMMARYThe Repulse Bay block (RBb) of the southern Melville Peninsula, Nunavut, lies within the Rae craton and exposes a large (50,000 km2) area of middle to lower crust. The block is composed of ca. 2.86 Ga and 2.73–2.71 Ga tonalite-trondhjemite-granodiorite (TTG) and granitic gneiss that was derived from an older 3.25 and 3.10 Ga crustal substrate. This period of crustal generation was followed by the emplacement of ca. 2.69–2.66 Ga enderbite, charnockite, and granitoid intrusions with entrained websterite xenoliths. These voluminous batholith-scale bodies (dehydrated and hydrated intrusions), and the associated websterite xenoliths, have similar whole rock geochemical properties, including fractionated light rare earth element (LREE)–heavy (H)REE whole rock patterns and negative Nb, Ti, and Ta anomalies. Dehydrated intrusions and websterite xenoliths also contain similar mineralogy (two pyroxene, biotite, interstitial amphibole) and similar pyroxene trace element compositions. Based on geochemical and mineralogical properties, the two lithologies are interpreted to be related by fractional crystallization, and to be the product of a magmatic cumulate processes. Reworking of the crust in a ca. 2.72 Ga subduction zone setting was followed by ca. 2.69 Ga upwelling of the asthenospheric mantle and the intrusion of massif-type granitoid plutons. Based on a dramatic increase in FeO, Zr, Hf, and LREE content of the most evolved granitoid components from the 2.69–2.66 Ga cumulate intrusion, we propose that those granitoid plutons were in part derived from a metasomatized mantle source enriched by fluids from the subducting oceanic slab that underwent further hybridization (via assimilation) with the crust. Large-scale, mantle-derived Neoarchean sanukitoid-type magmatism played a role in the development of a depleted lower crust and residual sub-continental lithospheric mantle, a crucial element in the preservation of the RBb.RÉSUMÉLe bloc de Repulse Bay (RBb) dans le sud de la pĂ©ninsule de Melville, au Nunavut, est situĂ© dans le craton de Rae et expose une large zone (50 000 km2) de croĂ»te moyenne Ă  infĂ©rieur. Ce bloc est composĂ© de tonalite-trondhjĂ©mite-granodiorite (TTG) datĂ© Ă  ca. 2,86 Ga et 2,73–2,71 Ga, et de gneiss granitique dĂ©rivĂ© d’un substrat crustal plus ancien datĂ© Ă  3,25 Ga et 3,10 Ga. Cette pĂ©riode de croissance crustale a Ă©tĂ© suivie par la mise en place entre ca. 2,69 et 2,66 Ga d’intrusions d’enderbite, charnockite et de granitoĂŻde incluant des xĂ©nolites d’entraĂźnement de websterite. Ces intrusions de taille batholitique (intrusions dĂ©shydratĂ©es et hydratĂ©es) ainsi que les xĂ©nolites d’entraĂźnement de websterite associĂ©s, ont des propriĂ©tĂ©s gĂ©ochimiques sur roche totale semblables notamment leurs profils de fractionnement des terres rares lĂ©gers (LREE) et des terres rares lourds (HREE) ainsi que leurs anomalies nĂ©gatives en Nb, Ti et Ta. Les intrusions dĂ©shydratĂ©es et les xĂ©nolites de websterite ont aussi des minĂ©ralogies similaires (deux pyroxĂšnes, biotite, amphibole interstitielle) ainsi que des compositions semblables en Ă©lĂ©ments traces de leurs pyroxĂšnes. Étant donnĂ© leurs propriĂ©tĂ©s gĂ©ochimiques et minĂ©ralogiques, ces deux lithologies sont interprĂ©tĂ©es comme provenant d’une cristallisation fractionnĂ©e, et comme Ă©tant le produit de processus d'accumulations magmatiques. Le remaniement de la croĂ»te dans un contexte de subduction vers ca. 2,72 Ga, a Ă©tĂ© suivi vers ca. 2,69 Ga d’une remontĂ©e du manteau asthĂ©nosphĂ©rique et de l’intrusion de granitoĂŻdes de type massif. D'aprĂšs l’importante augmentation en FeO, Zr, Hf et LREE dans les granitoĂŻdes les plus Ă©voluĂ©s du magmatisme ayant pris place entre ca. 2,69 Ga et 2,66 Ga, nous proposons que ces plutons aient Ă©tĂ© en partie dĂ©rivĂ©s d’une source mantĂ©lique mĂ©tasomatisĂ©e enrichies par des fluides d’une plaque ocĂ©anique en subduction et qui a subi une hybridation supplĂ©mentaire (par assimilation) avec la croĂ»te. Le magmatisme nĂ©o-archĂ©en de type sanukitoĂŻde, dĂ©rivĂ© du manteau et de grande Ă©chelle, a jouĂ© un rĂŽle dans le dĂ©veloppement d’une croĂ»te infĂ©rieure et d’un manteau lithosphĂ©rique continental rĂ©siduel appauvri, un Ă©lĂ©ment dĂ©terminant pour la prĂ©servation du RBb

    Evaluation of Pharmacy-implemented Medication Reconciliation Directed at Antiretroviral Therapy in Hospitalized HIV/AIDS Patients [letter]

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    Short communications published in Annals of Pharmacotherapy, 44(1)

    Identifying Task Engagement: Towards Personalised Interactions with Educational Robots

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    Abstract-The focus of this project is to design, develop and evaluate a new computational model for automatically detecting change in task engagement. This work will be applied to robotic tutors to enhance and support the learning experience, enabling timely pedagogical and empathic intervention. This work is intended to forward the current state of the art by 1) exploring how to automatically detect engagement with a learning task, 2) designing and developing new approaches to machine learning for adaptive platform-independent modelling and 3) evaluation of its effectiveness for building and maintaining learner engagement across different tutor embodiments, for example a physical and virtual embodiment

    Lithotectonic Framework of the Core Zone, Southeastern Churchill Province, Canada

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    The Core Zone, a broad region located between the Superior and North Atlantic cratons and predominantly underlain by Archean gneiss and granitoid rocks, remained until recently one of the less well known parts of the Canadian Shield. Previously thought to form part of the Archean Rae Craton, and later referred to as the Southeastern Churchill Province, it has been regarded as an ancient continental block trapped between the Paleoproterozoic Torngat and New Quebec orogens, with its relationships to the adjacent Superior and North Atlantic cratons remaining unresolved. The geochronological data presented herein suggest that the Archean evolution of the Core Zone was distinct from that in both the Superior and North Atlantic (Nain) cratons. Moreover, the Core Zone itself consists of at least three distinct lithotectonic entities with different evolutions, referred to herein as the George River, Mistinibi-Raude and Falcoz River blocks, that are separated by steeply-dipping, crustal-scale shear zones interpreted as paleosutures. Specifically, the George River Block consists of ca. 2.70 Ga supracrustal rocks and associated ca. 2.70–2.57 Ga intrusions. The Mistinibi-Raude Block consists of remnants of a ca. 2.37 Ga volcanic arc intruded by a ca. 2.32 Ga arc plutonic suite (Pallatin) and penecontemporaneous alkali plutons (Pelland and Nekuashu suites). It also hosts a coarse clastic cover sequence (the Hutte Sauvage Group) which contains detrital zircons provided from locally-derived, ca. 2.57–2.50 Ga, 2.37–2.32 Ga, and 2.10–2.08 Ga sources, with the youngest concordant grain dated at 1987 ± 7 Ma. The Falcoz River Block consists of ca. 2.89–2.80 Ga orthogneiss intruded by ca. 2.74–2.70 granite, tonalite, and granodiorite. At the western margin of the Core Zone, the George River Block and Kuujjuaq Domain may have been proximal by ca. 1.84 Ga as both appear to have been sutured by the 1.84–1.82 Ga De Pas Batholith, whereas at its eastern margin, the determination of metamorphic ages of ca. 1.85 to 1.80 Ga in the Falcoz River Block suggests protracted interaction with the adjacent Lac Lomier Complex during their amalgamation and suturing, but with a younger, ‘New Quebec’ overprint as well. The three crustal blocks forming the Core Zone add to a growing list of ‘exotic’ Archean to earliest Paleoproterozoic microcontinents and crustal slices that extend around the Superior Craton from the Grenville Front through Hudson Strait, across Hudson Bay and into Manitoba and Saskatchewan, in what was the Manikewan Ocean realm, which closed between ca. 1.83–1.80 Ga during the formation of supercontinent Nuna.RÉSUMÉLa Zone noyau, une vaste rĂ©gion situĂ©e entre les cratons du SupĂ©rieur et de l’Atlantique Nord et reposant principalement sur des gneiss archĂ©ens et des roches granitiques, est demeurĂ©e jusqu’à rĂ©cemment l’une des parties les moins bien connues du Bouclier canadien. ConsidĂ©rĂ©e auparavant comme faisant partie du craton archĂ©en de Rae, puis comme la portion sud-est de la Province de Churchill, on l’a perçue comme un ancien bloc continental piĂ©gĂ© entre les orogĂšnes palĂ©oprotĂ©rozoĂŻques des Torngat et du Nouveau-QuĂ©bec, ses relations avec les cratons supĂ©rieurs adjacents et de l’Atlantique Nord demeurant nĂ©buleuses. Les donnĂ©es gĂ©ochronologiques prĂ©sentĂ©es ici permettent de penser que l’évolution archĂ©enne de la Zone noyau a Ă©tĂ© diffĂ©rente de celle des cratons du SupĂ©rieur et de l’Atlantique Nord (Nain). De plus, la Zone noyau elle-mĂȘme se compose d’au moins trois entitĂ©s lithotectoniques distinctes avec des Ă©volutions diffĂ©rentes, appelĂ©es ici les blocs de la riviĂšre George, de Mistinibi-Raude et de la riviĂšre Falcoz, lesquels sont sĂ©parĂ©es par des zones de cisaillement crustales Ă  forte inclinaison, conçues comme des palĂ©osutures. Plus prĂ©cisĂ©ment, le bloc de la riviĂšre George est constituĂ© de roches supracrustales d'env. 2,70 Ga, et d’intrusions connexes d'env. 2,70–2,57 Ga. Le bloc Mistinibi-Raude est constituĂ© de vestiges d’un arc volcanique d'env. 2,37 Ga, recoupĂ© par une suite plutonique d’arc d'env. 2,32 Ga (Pallatin) et de plutons alcalins pĂ©nĂ©-contemporains (suites Pelland et Nekuashu). Il contient Ă©galement une sĂ©quence de couverture clastique grossiĂšre (le groupe Hutte Sauvage) renfermant des zircons dĂ©tritiques de sources locales, ĂągĂ©s d'env. 2,57–2,50 Ga, 2,37–2,32 Ga et 2,10–2,08 Ga, le grain concordant le plus jeune Ă©tant ĂągĂ© de 1987 ± 7 Ma. Le bloc de la riviĂšre Falcoz est formĂ© d’un orthogneiss ĂągĂ© d'env. 2,89–2,80 Ga, recoupĂ© par des intrusions de granite, tonalite et granodiorite ĂągĂ©es d'env. 2,74–2,70 Ga. À la marge ouest de la Zone noyau, le bloc de la riviĂšre George et du domaine de Kuujjuaq peuvent avoir Ă©tĂ© proximaux il y a 1,84 Ga env., car les deux semblent avoir Ă©tĂ© suturĂ©s par le batholithe De Pas il y a environ 1,84–1,82 Ga, alors qu’à sa marge est, la dĂ©termination des datations mĂ©tamorphiques de 1,85 Ă  1,80 Ga dans le bloc de la riviĂšre Falcoz suggĂšre une interaction prolongĂ©e avec le complexe adjacent du lac Lomier durant leur amalgamation et leur suture, mais affectĂ© aussi d’une surimpression « Nouveau QuĂ©bec » plus jeune. Les trois blocs crustaux formant la Zone noyau s’ajoutent Ă  une liste croissante de micro-continents et d’écailles crustales « exotiques » archĂ©ennes Ă  palĂ©oprotĂ©rozoĂŻques trĂšs prĂ©coces qui s’étalent autour du craton SupĂ©rieur depuis le front de Grenville jusqu’au Manitoba, Ă  travers le dĂ©troit d’Hudson, la baie d’Hudson jusque dans le Manitoba et la Saskatchewan, lĂ  oĂč s’étendait l’ocĂ©an Manikewan, lequel s’est refermĂ© il y a environ 1,83–1,80 Ga, pendant la formation du supercontinent Nuna

    How safe is your curry? Food allergy awareness of restaurant staff

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    Background: Incidents of severe and fatal anaphylaxis to accidentally ingested food allergens are increasing. Individuals are more likely to encounter difficulties when eating away from home. In restaurants, front-of-house and kitchen staff may be called upon to provide information about ingredients or ensure certain food allergens are excluded from dishes. Following a series of reactions related to the accidental ingestion of peanuts in curries we assessed food allergy awareness and allergen avoidance practices amongst the staff of Asian-Indian restaurants. Methods: A questionnaire survey was administered by telephone to one member of staff in each restaurant. Results: Fifty percent (40/80) of restaurants participated. Responders included managers, owners, waiters and chefs. Most (90%) had received food hygiene training, but only 15% food allergy training. 25% could name three common food allergens. 3 in 4 listed nuts, but less than 1in 5 mentioned peanuts. Common misunderstandings included 60% of staff believing an individual experiencing an allergic reaction should drink water to dilute the allergen. A less prevalent, but perhaps more concerning, was the misunderstanding that cooking food would prevent it causing an allergic reaction (25%). Despite poor knowledge, all respondents were comfortable and 65% were “very comfortable” with providing a “safe” meal for a customer with a food allergy. 60% expressed interest in future food allergy training. Conclusions: Despite high confidence in their own understanding of allergy, many staff lacked the knowledge to provide “safe” meals for food allergic customers. Traditionally tree nuts are a common ingredient in Asian-Indian dishes cuisine and there was widespread, but not universal, awareness of tree nuts as a common allergen. Peanuts were less commonly recognised as a common allergen, an observation of extreme concern as peanuts are being substituted for tree nuts as they are cheaper and avoid having to inflate meal prices. Our data highlights the need for greater training of restaurant staff. In parallel, food allergic customers need to exercise vigilance when making meal choices and develop skills to order a safe meal. The management of allergy is multifaceted, and this study indicates the importance of health professionals working beyond the clinical setting to collaborate with colleagues in the hospitality industry, public health and environmental health in coordinated endeavours to improve patient safety

    Developing a low-cost, simple-to-use electrochemical sensor for the detection of circulating tumour DNA in human fluids

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    It is well-known that two major issues, preventing improved outcomes from cancer are late diagnosis and the evolution of drug resistance during chemotherapy, therefore technologies that address these issues can have a transformative effect on healthcare workflows. In this work we present a simple, low-cost DNA biosensor that was developed specifically to detect mutations in a key oncogene (KRAS). The sensor employed was a screen-printed array of carbon electrodes, used to perform parallel measurements of DNA hybridisation. A DNA amplification reaction was developed with primers for mutant and wild type KRAS sequences which amplified target sequences from representative clinical samples to detectable levels in as few as twenty cycles. High levels of sensitivity were demonstrated alongside a clear exemplar of assay specificity by showing the mutant KRAS sequence was detectable against a significant background of wild type DNA following amplification and hybridisation on the sensor surface. The time to result was found to be 3.5 h with considerable potential for optimisation through assay integration. This quick and versatile biosensor has the potential to be deployed in a low-cost, point-of-care test where patients can be screened either for early diagnosis purposes or monitoring of response to therapy

    Cattle handling technique can induce fatigued cattle syndrome in cattle not fed a beta adrenergic agonist

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    Citation: Frese, D. A., Reinhardt, C. D., Bartle, S. J., Rethorst, D. N., Hutcheson, J. P., Nichols, W. T., . . . Thomson, D. U. (2016). Cattle handling technique can induce fatigued cattle syndrome in cattle not fed a beta adrenergic agonist. Journal of Animal Science, 94(2), 581-591. doi:10.2527/jas2015-9824Angus crossbred steers (n = 40; 563 +/- 44 kg) were used to examine the effects of handling method and fat thickness on the blood chemistry and physiology of market steers. Steers were blocked by backfat (BF) thickness and were randomly assigned to treatment groups: low-stress handling (LSH) and aggressive handling (AH). Cattle were then ran-domly assigned to one of 5 blocks containing 4 steers from the LSH and AH treatments. Steers in the LSH treatment were walked and AH cattle were run through a course of 1,540 m. Blood samples were obtained via jugular venipuncture before handling (BASE), at 770 m (LAP1), at 1,540 m (LAP2), and at1 h (1H) and 2 h (2H) after finishing the course. Blood samples were analyzed for plasma lactate (LAC), creatinine kinase (CK), base excess (BE), blood pH (pH), serum cortisol (CORT) concentrations, and venous carbon dioxide (PvCO2) and oxygen (PvO2) pressures. Heart rate (HR), respiratory rate (RR), and rectal temperature (TEMP) were measured at the same intervals. Cattle in the AH treatment had greater (P 0.14). Blood pH in AH cattle was decreased compared with that in LSH cattle (P 0.13) at BASE, 1H, or 2H. Heart rate and TEMP were increased in AH cattle compared to LSH (P > 0.01). Serum cortisol was increased (P < 0.05) in AH compared to that in LSH cattle at LAP1 (87.5 vs. 58.9 nmol/ L), LAP2 (144.4 vs. 93.1 nmol/ L), and 1H (113.5 vs. 53.1 nmol/ L). Although RR was not differ-ent between LSH and AH, PvCO2 was decreased in AH compared to that in LSH (P < 0.05) at LAP2 (30.6 vs. 39.3 mmHg) and PvO2 was increased at LAP1 (42.7 vs. 33.5 mmHg) and at LAP2 (51.5 vs. 36.6 mmHg). Lactate was increased in AH cattle in the thicker BF group at 1H (P < 0.05), and blood pH was decreased at LAP1, LAP2, and 1H (P < 0.05) compared to the thinner BF cohorts. Four AH steers became exhausted (EXH) and did not complete the course. Increased CK, decreased PvCO2, and muscle tremors occurred in EXH steers compared to non-exhausted AH cohorts. Results of this study show that AH causes physiologic and blood chemistry changes in steers, which can be potentially detrimental to cattle, emphasizing the need for lowstress handling practices
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