82 research outputs found

    Diel Flight Pattern and Flight Performance of Cactoblastis cactorum (Lepidoptera: Pyralidae) Measured on a Flight Mill: Influence of Age, Gender, Mating Status, and Body Size

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    Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) is an invasive herbivore that poses a serious risk to Opuntia cacti in North America. Knowledge of the flight behavior of the cactus moth is crucial for a better understanding of natural dispersal, and for both monitoring and control. We used computer-linked flight mills to investigate diel flight activity and flight performance in relation to gender, age, mating status, and body size. Maximal flight activity for both mated and unmated moths occurred during twilight, whereas flight activity was low during photophase. The total distance flown and the number of initiated flights within a diel cycle were higher in both unmated and mated females than in males, but the longest single flight was similar in both genders. These findings suggest that pheromone trap captures of males likely indicate the simultaneous presence of females and that mated females might even be in areas where males are not detected yet. Flight performance heterogeneity was large, with a small portion of the population (both males and females) performing long unbroken flights, whereas the majority made short flights. Females had higher pupal and adult body size and shorter longevity than males. A few individuals, particularly young mated females, flying long distances may be important for active spread of a population and the colonization of new habitats. Implications of this study in the control of the cactus moth by using the sterile insect technique are discusse

    Identification of Factors Influencing Flight Performance of Field-Collected and Laboratory-Reared, Overwintered, and Nonoverwintered Cactus Moths Fed with Field-Collected Host Plants

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    Environmental conditions during egg and larval development may influence the dispersal ability of insect pests, thus requiring seasonal adjustment of control strategies. We studied the longest single flight, total distance flown, and the number of flights initiated by wild Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) to determine whether the flight performance of overwintered cactus moths with a prolonged feeding phase during development differs from nonoverwintered cactus moths. Pupae of field-collected and laboratory-reared moths were transported together from the United States to Switzerland, and flight mills were used to characterize the flight capacity of 24- to 48-h-old adults during their most active period of the diel cycle. The lack of seasonal variation in flight performance of those moths that developed under controlled environment but were fed with field-collected Opuntia cacti showed that seasonal changes in host plant quality did not affect flight. This consistent flight performance in the mass-reared laboratory population throughout the year is beneficial for sterile insect technique programs, which aim to limit the dispersal of this pest. For field-collected C. cactorum, the larger overwintered females performed similarly to nonoverwintered females, indicating that longer feeding time at lower temperature increases body size but does not influence female flight capacity. Young mated females had a similar flight capacity to unmated ones, suggesting that gravid females may play an important role in invading new habitats. For males, overwintering increased the proportion of long-distance flyers, suggesting that they are well-adapted to locate the more sparsely dispersed females in the sprin

    Motion Rail: A Virtual Reality Level Crossing Training Application

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    This paper presents the development and usability testing of a Virtual Reality (VR) based system named 'Motion Rail' for training children on railway crossing safety. The children are to use a VR head mounted device and a controller to navigate the VR environment to perform a level crossing task and they will receive instant feedback on pass or failure on a display in the VR environment. Five participants consisting of two male and three females were considered for the usability test. The outcomes of the test was promising, as the children were very engaging and will like to adopt this training approach in future safety training

    Diffusion of Subsidized ACTs in Accredited Drug Shops in Tanzania: Determinants of Stocking and Characteristics of Early and Late Adopters.

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    Many households in sub-Saharan Africa utilize the private sector as a primary source of treatment for malaria episodes. Expanding access to effective treatment in private drug shops may help reduce incidence of severe disease and mortality. This research leveraged a longitudinal survey of stocking of subsidized artemisinin combination therapies (ACTs), an effective anti-malarial, in Accredited Drug Dispensing Outlets (ADDOs) in two regions of Tanzania. This provided a unique opportunity to explore shop and market level determinants of product diffusion in a developing country retail market. 356 ADDOs in the Rukwa and Mtwara regions of Tanzania were surveyed at seven points between Feb 2011 and May 2012. Shop level audits were used to measure the availability of subsidized ACTs at each shop. Data on market and shop level factors were collected during the survey and also extracted from GIS layers. Regression and network based methodologies were used. Shops classified as early and late adopters, following Rogers' model of product diffusion, were compared. The Bass model of product diffusion was applied to determine whether shops stocked ACTs out of a need to imitate market competitors or a desire to satisfy customer needs. Following the introduction of a subsidy for ACTs, stocking increased from 12% to nearly 80% over the seven survey rounds. Stocking was influenced by higher numbers of proximal shops and clinics, larger customer traffic and the presence of a licensed pharmacist. Early adopters were characterized by a larger percentage of customers seeking care for malaria, a larger catchment and sourcing from specific wholesalers/suppliers. The Bass model of product diffusion indicated that shops were adopting products in response to competitor behavior, rather than customer demand. Decisions to stock new pharmaceutical products in Tanzanian ADDOs are influenced by a combination of factors related to both market competition and customer demand, but are particularly influenced by the behavior of competing shops. Efforts to expand access to new pharmaceutical products in developing country markets could benefit from initial targeting of high profile shops in competitive markets and wholesale suppliers to encourage faster product diffusion across all drug retailers

    Good practice in health care for migrants: views and experiences of care professionals in 16 European countries

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    <p>Abstract</p> <p>Background</p> <p>Health services across Europe provide health care for migrant patients every day. However, little systematic research has explored the views and experiences of health care professionals in different European countries. The aim of this study was to assess the difficulties professionals experience in their service when providing such care and what they consider constitutes good practice to overcome these problems or limit their negative impact on the quality of care.</p> <p>Methods</p> <p>Structured interviews with open questions and case vignettes were conducted with health care professionals working in areas with high proportion of migrant populations in 16 countries. In each country, professionals in nine primary care practices, three accident and emergency hospital departments, and three community mental health services (total sample = 240) were interviewed about their views and experiences in providing care for migrant patients, i.e. from first generation immigrant populations. Answers were analysed using thematic content analysis.</p> <p>Results</p> <p>Eight types of problems and seven components of good practice were identified representing all statements in the interviews. The eight problems were: language barriers, difficulties in arranging care for migrants without health care coverage, social deprivation and traumatic experiences, lack of familiarity with the health care system, cultural differences, different understandings of illness and treatment, negative attitudes among staff and patients, and lack of access to medical history. The components of good practice to overcome these problems or limit their impact were: organisational flexibility with sufficient time and resources, good interpreting services, working with families and social services, cultural awareness of staff, educational programmes and information material for migrants, positive and stable relationships with staff, and clear guidelines on the care entitlements of different migrant groups. Problems and good care components were similar across the three types of services.</p> <p>Conclusions</p> <p>Health care professionals in different services experience similar difficulties when providing care to migrants. They also have relatively consistent views on what constitutes good practice. The degree to which these components already are part of routine practice varies. Implementing good practice requires sufficient resources and organisational flexibility, positive attitudes, training for staff and the provision of information.</p

    The importance of olfactory and visual cues in developing better monitoring tools for \u3ci\u3eSirex noctilio\u3c/i\u3e (Hymenoptera: Siricidae)

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    1. To improve the monitoring of the invasive European woodwasp, both sexes of Sirex noctilio were studied in a walk-in wind tunnel.We evaluated three trap types: unbaited traps, traps baited with a three-component pheromone lure and traps baited with a commercial Sirex kairomone lure and ultraviolet light. 2. When no lure was present, the black intercept trap caught more females than the clear jar trap. The increase in pheromone concentration from 0.1 to 1mg increased the capture of females, and not males, in the black intercept panel trap. Both of these findings suggest that the visual cues provided by the black intercept trap play an important role in attraction for females. 3. Capture rates between unbaited clear versus black intercept traps did not differ but the addition of a ultraviolet light increased trap efficacy. Intercept traps baited with light were more attractive than the commercial kairomone lure. 4. Both olfactory and visual cues were found to play important roles in the response of S. noctilio to traps. A black trap may enhance the capture of females, whereas the addition of ultraviolet light could enhance capture for both sexes. Integrating these different components may help in developing an improved species-specific trap for S. noctilio

    Could the high level of cirrhosis in Central and Eastern Europe be due partly to the quality of alcohol consumed? An exploratory investigation

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    BACKGROUND: The burden of alcohol-related diseases differs widely among countries. Since the 1980s, a band of countries in Central and Eastern Europe have experienced a steep rise in deaths from chronic liver diseases and cirrhosis. A possible risk factor is the consumption of illegally produced home-made spirits in these countries containing varying amounts of aliphatic alcohols and which may be hepatotoxic. However, little is known about the composition of such beverages. AIMS: To compare the concentration of short-chain aliphatic alcohols in spirits from illegal and legal sources in Hungary. DESIGN: Samples taken from commercial retailers and illegal sources were collected and their aliphatic patterns and alcohol concentrations were determined by gas chromatographic/mass spectrometric (GC/MS) analysis. FINDINGS: The concentrations of methanol, isobutanol, 1-propanol, 1-butanol, 2-butanol and isoamyl alcohol were significantly higher in home-made spirits than those of from commercial sources. CONCLUSIONS: The results suggest that the consumption of home-made spirits is an additional risk factor for the development of alcohol-induced cirrhosis and may have contributed to high level of liver cirrhosis mortality in Central and Eastern Europe. Restrictions on supply and sale of alcohol from illicit sources are needed urgently to reduce significantly the mortality from chronic liver disease

    Training children in Safe Use of Designated Crossing

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    Despite the intention that they should increase pedestrian safety, designated crossings (that is, marked out points for road crossing such as stand-alone signal-controlled crossings, zebras, and junction lights with a pedestrian phase) are known to be problematic in character (Carsten, Sherborne and Rothengatter, 1998). Bly, Dix and Stephenson (1999), comparing child pedestrian injury events in Great Britain, France and the Netherlands, found that children in Britain face a higher risk when using designated crossings. The most recent figures (2001) on pedestrian casualties for the UK bear out this point, with cases at all levels of severity tending to be more common at designated crossing sites than within 50 metres of them. Whilst the precise reasons for this are unclear, it may be the result of children in Britain also making less use of such crossings, and thus having a poorer grasp of what behaviours are appropriate at these points and why. It would therefore be valuable to ascertain what children do understand about designated crossings, and to attempt to ameliorate any gaps via educational intervention, especially since there has been little previous work of this kind. Indeed, at present, none of the practical pedestrian training schemes for children in use in the UK address safe use of designated crossings
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