2,486 research outputs found

    Quantum Correlations from the Conditional Statistics of Incomplete Data

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    We study, in theory and experiment, the quantum properties of correlated light fields measured with click-counting detectors providing incomplete information on the photon statistics. We establish a correlation parameter for the conditional statistics, and we derive the corresponding nonclassicality criteria for detecting conditional quantum correlations. Classical bounds for Pearson's correlation parameter are formulated that allow us, once they are violated, to determine nonclassical correlations via the joint statistics. On the one hand, we demonstrate nonclassical correlations in terms of the joint click statistics of light produced by a parametric down conversion source. On the other hand, we verify quantum correlations of a heralded, split single-photon state via the conditional click statistics together with a generalization to higher-order moments. We discuss the performance of the presented nonclassicality criteria to successfully discern joint and conditional quantum correlations. Remarkably, our results are obtained without making any assumptions on the response function, quantum efficiency, and dark-count rate of the photodetectors

    Timing of Tertiary Extension in the Railroad Valley Pioche Transect, Nevada: Constraints from Ar-40/Ar-39 Ages of Volcanic Rocks

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    Time-space relations of extension and volcanism place critical constraints on models of Basin and Range extensional processes. This paper addresses such relations in a 130-km-wide transect in the eastern Great Basin, bounded on the east by the Ely Springs Range and on the west by the Grant and Quinn Canyon ranges. Stratigraphic and structural data, combined with 40Ar/39Ar isotopic ages of volcanic rocks, document a protracted but distinctly episodic extensional history. Field relations indicate four periods of faulting. Only one of these periods was synchronous with nearby volcanic activity, which implies that volcanism and faulting need not be associated closely in space and time. Based on published dates and the analyses reported here, the periods of extension were (1) prevolcanic (pre-32 Ma), (2) early synvolcanic (30 to 27 Ma), (3) immediately postvolcanic (about 16 to 14 Ma), and (4) Pliocene to Quaternary. The break between the second and third periods is distinct. The minimum gap between the first two periods is 2 Ma, but the separation may be much larger. Temporal separation of the last two periods is only suggested by the stratigraphic record and cannot be rigorously demonstrated with present data. The three younger periods of faulting apparently occurred across the entire transect. The oldest period is recognized only at the eastern end of the transect, but appears to correlate about 150 km northward along strike with extension in the Northern Snake Range-Kern Mountains area. Therefore the oldest period also is regional in extent, but affected a different area than that affected by younger periods. This relation suggests that distinct extensional structures and master detachment faults were active at different times. The correlation of deformation periods of a few million years duration across the Railroad Valley-Pioche transect suggests that the scale of active extensional domains in the Great Basin may be greater than 100 km across strike

    'Men give in to chips and beer too easily': How working-class men make sense of gender differences in health

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    This article, based on qualitative research with working-class men, explores men's perceptions and experiences regarding gender differences in health. It demonstrates how men put forward a range of behavioural/cultural, materialist/structural and psychosocial factors, which were believed to differently impact men's health compared to women. A common theme underpinning their explanations was the ways in which men and women were located within two distinct gender categories. These characterisations were used to explain why health-damaging beliefs and behaviours were more prevalent among men and also why men were better suited for certain kinds of jobs, albeit with potential costs to their health. Men also believed that women were protected from the damaging physical and emotional impact of manual employment because of their primary role within the home and because they were less emotionally robust, which required men to shield women from the stresses they experienced. However, men's emotional withdrawal can also be viewed as another example of how men use whatever resources are available to achieve and maintain dominance over women. Finally, the article demonstrates how a gender- and class-based approach can capture the impact of men's health-related practices alongside the broader cultural and structural influences on men's health

    Technological and Implementation Issues in Moodle-Based Digital Badge System

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    Digital badges, touted as a gamification tool that can potentially influence learner motivation, engagement and participation, are being used increasingly in a variety of educational domains to facilitate and motivate learning. Using a badge system design implemented in the Moodle learning management platform, data was collected from four experiments from 2015 to 2017 to examine the effects of gamification with the use of digital badges on introductory programming students' intrinsic motivation. This paper provides an in-depth examination of seldomly discussed technological and implementation issues we encountered in implementing our Moodle-based badge system, worthy of exploration to support future gamification studies in this area. Our gamified implementation is analyzed according to five main factors primarily adopted from an IT implementation framework: (1) assessment of needs, (2) choice of technology, (3) technological infrastructure, (4) system and environmental factors and (5) evaluation. The findings highlight enabling and challenging factors associated with the technology and badge implementation. Our experience shows that badge systems may be influenced by contextual factors such as cost and scale of implementation. We provide recommendations to guide educational stakeholders, particularly those considering Moodle as their badge implementation platform

    Technological and Implementation Issues in Moodle-Based Digital Badge System

    Get PDF
    Digital badges, touted as a gamification tool that can potentially influence learner motivation, engagement and participation, are being used increasingly in a variety of educational domains to facilitate and motivate learning. Using a badge system design implemented in the Moodle learning management platform, data was collected from four experiments from 2015 to 2017 to examine the effects of gamification with the use of digital badges on introductory programming students' intrinsic motivation. This paper provides an in-depth examination of seldomly discussed technological and implementation issues we encountered in implementing our Moodle-based badge system, worthy of exploration to support future gamification studies in this area. Our gamified implementation is analyzed according to five main factors primarily adopted from an IT implementation framework: (1) assessment of needs, (2) choice of technology, (3) technological infrastructure, (4) system and environmental factors and (5) evaluation. The findings highlight enabling and challenging factors associated with the technology and badge implementation. Our experience shows that badge systems may be influenced by contextual factors such as cost and scale of implementation. We provide recommendations to guide educational stakeholders, particularly those considering Moodle as their badge implementation platform

    Oral dosing with papaya latex is an effective anthelmintic treatment for sheep infected with Haemonchus contortus

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    Background The cysteine proteinases in papaya latex have been shown to have potent anthelmintic properties in monogastric hosts such as rodents, pigs and humans, but this has not been demonstrated in ruminants. Methods In two experiments, sheep were infected concurrently with 5,000 infective larvae of Haemonchus contortus and 10,000 infective larvae of Trichostrongylus colubriformis and were then treated with the supernatant from a suspension of papaya latex from day 28 to day 32 post-infection. Faecal egg counts were monitored from a week before treatment until the end of the experiment and worm burdens were assessed on day 35 post-infection. Results We found that the soluble fraction of papaya latex had a potent in vivo effect on the abomasal nematode H. contortus, but not on the small intestinal nematode T. colubriformis. This effect was dose-dependent and at tolerated levels of gavage with papaya latex (117 μmol of active papaya latex supernatant for 4 days), the H. contortus worm burdens were reduced by 98%. Repeated treatment, daily for 4 days, was more effective than a single dose, but efficacy was not enhanced by concurrent treatment with the antacid cimetidine. Conclusions Our results provide support for the idea that cysteine proteinases derived from papaya latex may be developed into novel anthelmintics for the treatment of lumenal stages of gastro-intestinal nematode infections in sheep, particularly those parasitizing the abomasum

    Estimating the changing nature of Scotland's health inequalities using a multivariate spatiotemporal model

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    Health inequalities are the unfair and avoidable differences in people's health between different social groups. These inequalities have a huge influence on people's lives, particularly those who live at the poorer end of the socio‐economic spectrum, as they result in prolonged ill health and shorter lives. Most studies estimate health inequalities for a single disease, but this will give an incomplete picture of the overall inequality in population health. Here we propose a novel multivariate spatiotemporal model for quantifying health inequalities in Scotland across multiple diseases, which will enable us to understand better how these inequalities vary across disease and have changed over time. In developing this model we are interested in estimating health inequalities between Scotland's 14 regional health boards, who are responsible for the protection and improvement of their population's health. The methodology is applied to hospital admissions data for cerebrovascular disease, coronary heart disease and respiratory disease, which are three of the leading causes of death, from 2003 to 2012 across Scotland

    Increased expression of a microRNA correlates with anthelmintic resistance in parasitic nematodes

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    Resistance to anthelmintic drugs is a major problem in the global fight against parasitic nematodes infecting humans and animals. While previous studies have identified mutations in drug target genes in resistant parasites, changes in the expression levels of both targets and transporters have also been reported. The mechanisms underlying these changes in gene expression are unresolved. Here, we take a novel approach to this problem by investigating the role of small regulatory RNAs in drug resistant strains of the important parasite Haemonchus contortus. microRNAs (miRNAs) are small (22 nt) non-coding RNAs that regulate gene expression by binding predominantly to the 3′ UTR of mRNAs. Changes in miRNA expression have been implicated in drug resistance in a variety of tumor cells. In this study, we focused on two geographically distinct ivermectin resistant strains of H. contortus and two lines generated by multiple rounds of backcrossing between susceptible and resistant parents, with ivermectin selection. All four resistant strains showed significantly increased expression of a single miRNA, hco-miR-9551, compared to the susceptible strain. This same miRNA is also upregulated in a multi-drug-resistant strain of the related nematode Teladorsagia circumcincta. hco-miR-9551 is enriched in female worms, is likely to be located on the X chromosome and is restricted to clade V parasitic nematodes. Genes containing predicted binding sites for hco-miR-9551 were identified computationally and refined based on differential expression in a transcriptomic dataset prepared from the same drug resistant and susceptible strains. This analysis identified three putative target mRNAs, one of which, a CHAC domain containing protein, is located in a region of the H. contortus genome introgressed from the resistant parent. hco-miR-9551 was shown to interact with the 3′ UTR of this gene by dual luciferase assay. This study is the first to suggest a role for miRNAs and the genes they regulate in drug resistant parasitic nematodes. miR-9551 also has potential as a biomarker of resistance in different nematode species
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