371 research outputs found

    Woodland Type and Spatial Distribution of Nymphal Ixodes scapularis (Acari: Ixodidae)

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    Spatial distribution patterns of black-legged ticks, Ixodes scapularis, in deciduous and coniferous woodlands were studied by sampling ticks in different woodland types and at sites from which deer had been excluded and by quantifying movement patterns of tick host animals (mammals and birds) at the Lighthouse Tract, Fire Island, NY, from 1994 to 2000. Densities of nymphal ticks were greater in deciduous than coniferous woods in 3 of 7 yr. Only engorged ticks survived the winter, and overwintering survival of engorged larvae in experimental enclosures did not differ between deciduous and coniferous woods. Nymphs were not always most abundant in the same forest type as they had been as larvae, and the habitat shift between life stages differed in direction in different years. Therefore, forest type by itself did not account for tick distribution patterns. Nymphal densities were lower where deer had been excluded compared with areas with deer present for 3 yr after exclusion, suggesting that movement patterns of vertebrate hosts influenced tick distribution, but nymphal densities increased dramatically in one of the enclosures in the fourth year. Therefore, movements of ticks on animal hosts apparently contribute substantially to tick spatial distribution among woodland types, but the factor(s) that determine spatial distribution of nymphal I. scapularis shift from year to year

    Luring houseflies (Musca domestica Diptera: Muscidae) to traps: Do cuticular hydrocarbons and visual cues increase catch?

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    Houseflies (Musca domestica L.) are a major pest species of livestock units and landfill sites used for the disposal of domestic waste. Of the many methods used to limit housefly populations, the most common are chemical control and lure-and-kill trap systems. Insecticide resistance has seen increased emphasis on lure-and-kill, but the success of this method relies on effective attraction of houseflies using olfactory or visual stimuli. Here we examine the efficacy of olfactory (cuticular hydrocarbons) or visual (colours and groups of flies) attractants in a poultry unit. Despite simulating the cuticular hydrocarbon profiles of male and female houseflies, we found no significant increase in the number of individuals lured to traps, or any sex-specific responses. Similarly the use of target colours selected to match the three peaks in housefly visual spectral sensitivity yielded no improvement in catch rate. We also demonstrate that male and female flies have significantly different spectral reflectance (males are brighter between 320-470nm; females are brighter between 470-670nm). An experiment incorporating groups of recently killed flies from which cuticular hydrocarbons were either removed by solvent or left in-tact also failed to show any evidence of olfactory or visual attraction for houseflies of either sex. Thus variations on the most commonly applied methods of luring houseflies to traps in commercial livestock units failed to significantly increase capture rates. Our results support commonly observed inconsistencies associated with using olfactory or visual stimuli in lure-and-kill systems, possibly because field conditions lessen the attractant properties observed in laboratory experiments

    Experimental Evidence for the Effects of Calcium and Vitamin D on Bone: A Review

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    Animal models fed low calcium diets demonstrate a negative calcium balance and gross bone loss while the combination of calcium deficiency and oophorectomy enhances overall bone loss. Following oophorectomy the dietary calcium intake required to remain in balance increases some 5 fold, estimated to be approximately 1.3% dietary calcium. In the context of vitamin D and dietary calcium depletion, osteomalacia occurs only when low dietary calcium levels are combined with low vitamin D levels and osteoporosis occurs with either a low level of dietary calcium with adequate vitamin D status or when vitamin D status is low in the presence of adequate dietary calcium intake. Maximum bone architecture and strength is only achieved when an adequate vitamin D status is combined with sufficient dietary calcium to achieve a positive calcium balance. This anabolic effect occurs without a change to intestinal calcium absorption, suggesting dietary calcium and vitamin D have activities in addition to promoting a positive calcium balance. Each of the major bone cell types, osteoblasts, osteoclasts and osteocytes are capable of metabolizing 25 hydroxyvitamin D (25D) to 1,25 dihydroxyvitamin D (1,25D) to elicit biological activities including reduction of bone resorption by osteoclasts and to enhance maturation and mineralization by osteoblasts and osteocytes. Each of these activities is consistent with the actions of adequate circulating levels of 25D observed in vivo

    Racial Disparity and Socioeconomic Status in Association With Survival in Older Men with Local/Regional Stage Prostate Cancer: Findings From a Large Community-Based Cohort

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    BACKGROUND Few studies have examined the outcomes for Hispanic men with prostate carcinoma and incorporated socioeconomic factors in association with race/ethnicity in affecting survival, adjusting for factors on cancer stage, grade, comorbidity, and treatment. METHODS We studied a population-based cohort of 61,228 men diagnosed with local or regional stage prostate carcinoma at age 65 years or older between 1992 and 1999 in the 11 SEER (Surveillance, Epidemiology, and End Results) areas, identified from the SEER-Medicare linked data with up to 11 years of followup. RESULTS Low socioeconomic status was significantly associated with decreasing survival in all men with prostate carcinoma. Those living in the community with the lowest quartile of socioeconomic status were 31% more likely to die than those living in the highest quartile (hazard ratio [HR] of all-cause mortality: 1.31; 95% confidence interval [CI]: 1.25–1.36) after adjustment for patient age, comorbidity, Gleason score, and treatment. The HR remained almost unchanged after controlling for race/ethnicity (HR: 1.32; 95% CI: 1.26–1.38). Compared with Caucasians, the risk of mortality in African American men was marginally significantly higher (HR: 1.06; 95% CI: 1.01–1.11) after controlling for education, and no longer significant after adjusting for poverty, income, or composite socioeconomic variable; the HR was lower for Hispanic men (HR: 0.80; 95% CI: 0.72–0.89) after adjustment for education and other socioeconomic variables. CONCLUSION Racial disparity in survival among men with local or regional prostate carcinoma was largely explained by socioeconomic status and other factors. Lower socioeconomic status appeared to be one of the major barriers to achieving comparable outcomes for men with prostate carcinoma

    Development of a single-session physiotherapy and self-management intervention for the treatment of primary traumatic anterior shoulder dislocation for the ‘Acute Rehabilitation following Traumatic anterior shoulder dISlocAtioN (ARTISAN)’ multi centre RCT

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    Objective Optimum physiotherapy management for people with a conservatively managed primary traumatic anterior shoulder dislocation is not known. The purpose of the ARTISAN trial is to compare the clinical and cost-effectiveness of a course of usual care physiotherapy with a single session of physiotherapy and self-management, the ARTISAN intervention. ARTISAN is a UK multi-centre, two-arm, parallel group, randomised controlled trial with 1:1 treatment allocation. Design The intervention was developed following the Medical Research Council framework for developing and evaluating complex interventions and will be reported in line with the template for intervention description and replication checklist (TIDieR) and the Consensus on Exercise Reporting Template (CERT). It was informed by published research, national clinical guidelines, current clinical practice and patient and public involvement. Results The ARTISAN intervention comprises education (Phase 1), progressive exercise (Phase 2 and Phase 3) and an optional return to sport component (Phase 4). Behaviour change strategies are embedded throughout intervention. The single session of physiotherapy is delivered by a chartered physiotherapist, within the first six weeks of injury, in an NHS outpatient setting. At the end of the initial session, paper-based booklets and/or a patient website with the same content are provided to participants to aid self-management and progression though the four phases of the trial intervention. Conclusion The ARTISAN intervention was successfully implemented throughout the internal pilot and is suitable for testing in the subsequent definitive RCT ARTISAN trial

    CCTV observation: The effects of event type and instructions on fixation behaviour in an applied change blindness task

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    Little is known about how observers’ scanning strategies affect performance when monitoring events in CCTV footage. We examined the fixation behaviour of change detectors and non-detectors monitoring dynamic scenes. 147 participants observed mock CCTV video featuring either a mock crime or no crime. Participants were instructed to look for a crime, something unusual, or simply to watch the video. In both videos, two of the people depicted switched locations. Eye movements (the number of fixations on the targets and the average length of each fixation on targets) were recorded prior to and during the critical change period. Change detection (24% overall) was unaffected by event type or task instruction. Fixation behaviour differed significantly between the criminal and non-criminal event conditions. There was no effect of instructions on fixation behaviour. Change detectors fixated for longer on the target directly before the change than did non-detectors. Although fixation behaviour before change predicted change detection, fixation count and durations during the critical change period did not. These results highlight the potential value of studying fixation behaviour for understanding change blindness during complex, cognitively demanding tasks (e.g., CCTV surveillance)

    Response of the solar atmosphere to magnetic field evolution in a coronal hole region

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    Methods. We study an equatorial CH observed simultaneously by HINODE and STEREO on July 27, 2007. The HINODE/SP maps are adopted to derive the physical parameters of the photosphere and to research the magnetic field evolution and distribution. The G band and Ca II H images with high tempo-spatial resolution from HINODE/BFI and the multi-wavelength data from STEREO/EUVI are utilized to study the corresponding atmospheric response of different overlying layers. Results. We explore an emerging dipole locating at the CH boundary. Mini-scale arch filaments (AFs) accompanying the emerging dipole were observed with the Ca II H line. During the separation of the dipolar footpoints, three AFs appeared and expanded in turn. The first AF divided into two segments in its late stage, while the second and third AFs erupted in their late stages. The lifetimes of these three AFs are 4, 6, 10 minutes, and the two intervals between the three divisions or eruptions are 18 and 12 minutes, respectively. We display an example of mixed-polarity flux emergence of IN fields within the CH and present the corresponding chromospheric response. With the increase of the integrated magnetic flux, the brightness of the Ca II H images exhibits an increasing trend. We also study magnetic flux cancellations of NT fields locating at the CH boundary and present the obvious chromospheric and coronal response. We notice that the brighter regions seen in the 171 A images are relevant to the interacting magnetic elements. By examining the magnetic NT and IN elements and the response of different atmospheric layers, we obtain good positive linear correlations between the NT magnetic flux densities and the brightness of both G band (correlation coefficient 0.85) and Ca II H (correlation coefficient 0.58).Comment: 9 pages, 9 figures. A&A, in pres

    Modified Habitats Influence Kelp Epibiota via Direct and Indirect Effects

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    Addition of man-made structures alters abiotic and biotic characteristics of natural habitats, which can influence abundances of biota directly and/or indirectly, by altering the ecology of competitors or predators. Marine epibiota in modified habitats were used to test hypotheses to distinguish between direct and indirect processes. In Sydney Harbour, kelps on pier-pilings supported greater covers of bryozoans, particularly of the non-indigenous species Membranipora membranacea, than found on natural reefs. Pilings influenced these patterns and processes directly due to the provision of shade and indirectly by altering abundances of sea-urchins which, in turn, affected covers of bryozoans. Indirect effects were more important than direct effects. This indicates that artificial structures affect organisms living on secondary substrata in complex ways, altering the biodiversity and indirectly affecting abundances of epibiota. Understanding how these components of habitats affect ecological processes is necessary to allow sensible prediction of the effects of modifying habitats on the ecology of organisms
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