1,001 research outputs found

    Evaluation of Methods for Sampling the Malaria Vector Anopheles darlingi (Diptera, Culicidae) in Suriname and the Relation With Its Biting Behavior

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    The effectiveness of CO2-baited and human-baited mosquito traps for the sampling of Anopheles darlingi Root was evaluated and compared with human landing collections in Suriname. Biting preferences of this mosquito on a human host were studied and related to trapping data. Traps used were the Centers for Disease Control and Prevention Miniature Light trap, the BG Sentinel mosquito trap, the Mosquito Magnet Liberty Plus mosquito trap (MM-Plus), and a custom-designed trap. Carbon dioxide and humans protected by a bed net were used as bait in the studies. The number of An. darlingi collected was greater with human landing collections than with all other collection methods. An. darlingi did not show a preference for protected humans over CO2 bait. The BG Sentinel mosquito trap with CO2 or human odor as bait and the MM-Plus proved the best alternative sampling tools for An. darlingi. The BG Sentinel mosquito trap with CO2 or human odor as bait was also very efficient at collecting Culex spp. In a field study on biting preferences of wild An. darlingi, the females showed directional biting behavior (P <0.001), with a majority of females (93.3%) biting the lower legs and feet when approaching a seated human host. Higher efficiency of the closer-to-the-ground collecting MM-Plus and BG Sentinel mosquito trap when compared with the other trapping methods may be a result of a possible preference of this mosquito species for low-level biting. It is concluded that odor-baited sampling systems can reliably collect An. darlingi, but the odor bait needs to be improved, for instance, by including host-specific volatiles, to match live human baits

    Carbon dioxide baited trap catches do not correlate with human landing collections of Anopheles aquasalis in Suriname

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    Three types of carbon dioxide-baited traps, i.e., the Centers for Disease Control Miniature Light Trap without light, the BioGents (BG) Sentinel Mosquito Trap (BG-Sentinel) and the Mosquito Magnet® Liberty Plus were compared with human landing collections in their efficiency in collecting Anopheles (Nyssorhynchus) aquasalis mosquitoes. Of 13,549 total mosquitoes collected, 1,019 (7.52%) were An. aquasalis. Large numbers of Culex spp were also collected, in particular with the (BG-Sentinel). The majority of An. aquasalis (83.8%) were collected by the human landing collection (HLC). None of the trap catches correlated with HLC in the number of An. aquasalis captured over time. The high efficiency of the HLC method indicates that this malaria vector was anthropophilic at this site, especially as carbon dioxide was insufficiently attractive as stand-alone bait. Traps using carbon dioxide in combination with human odorants may provide better results

    Mechanical Design of the SMC (Short Model Coil) Dipole Magnet

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    The Short Model Coil (SMC) working group was set in February 2007 within the Next European Dipole (NED) program, in order to develop a short-scale model of a Nb3_{3}Sn dipole magnet. The SMC group comprises four laboratories: CERN/TE-MSC group (CH), CEA/IRFU (FR), RAL (UK) and LBNL (US). The SMC magnet was originally conceived to reach a peak field of about 13 T on conductor, using a 2500 A/mm2 Powder-In-Tube (PIT) strand. The aim of this magnet device is to study the degradation of the magnetic properties of the Nb3_{3}Sn cable, by applying different level of pre-stress. To fully satisfy this purpose, a versatile and easy-to-assemble structure has to be realized. The design of the SMC magnet has been developed from an existing dipole magnet, the SD01, designed, built and tested at LBNL with support from CEA. In this paper we will describe the mechanical optimization of the dipole, starting from a conceptual configuration based on a former magnetic analysis. Two and three-dimensional Finite Element Method (FEM) models have been implemented in ANSYS™ and in CAST3M, aiming at setting the mechanical parameters of the dipole magnet structure, thus fulfilling the design constraints imposed by the materials

    Construction and measurement of the pre-series twin aperture resistive quadrupole magnet for the LHC beam cleaning insertions

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    CERN's Large Hadron Collider (LHC) requires 48 twin aperture resistive quadrupoles in the beam cleaning insertions. Canada is contributing these magnets to CERN in the framework of the TRIUMF-LHC collaboration contracts. A pre-series magnet was produced by Canadian industry and delivered in March 2001. This magnet incorporates important design changes that resulted from experience with a prototype magnet. The construction of this pre-series magnet and the measurements made at ALSTOM and at CERN are reported. A comparison is made between high precision pole distance measurements and the magnetic measurements performed with a rotating coil mole. Conclusions for series production and possibilities for multipole corrections are outlined. (6 refs)

    Experimental and analytical assessment of the capacity of traditional single notch joints and impact of retrofitting by self-tapping screws

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    The joints are the most crucial parts of a timber building and determine the overall structural behaviour, load-bearing capacity and failure mechanisms. Therefore, keeping the joints fully functional is of utmost importance to ensure a desired structural performance of timber buildings under various actions. Since replacement of damaged parts of an existing structure is expensive and in many cases very difficult to perform in situ, retrofitting to avoid failure becomes an increasingly widespread strategy. In this paper, the capacity and failure mechanisms of single notch joints before and after a simple retrofitting intervention by means of self-tapping screws were investigated. To this end, a series of tests were carried out during the 5th COST FP 1101 Training School, held in University of Minho, Portugal. The joints were first tested under compression, and the load-bearing capacity values obtained at the end of tests were compared to the capacity values calculated using theoretical models proposed in a variety of national codes. Then, tested joints were retrofitted using self-tapping screws. The retrofitting strategy aimed to prevent failure mechanism that was shown to dominate joints' behaviour in the unreinforced state, rather than to increase the load-bearing capacity or stiffness. The impact of retrofitting on the joints' performance was discussed and the success of the proposed intervention was further debated.- The authors are grateful to COST Action for funding the FP1101 and RILEM 245 Training School at University of Minho in Guimaraes, Portugal, and to Dr. Jorge M. Branco and other members of Civil Engineering Department for making this study possible

    Electrical Integrity Tests during Production of the LHC Dipoles

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    For the LHC dipoles, mandatory electrical integrity tests are performed to qualify the cold mass (CM) at four production stages: individual pole, collared coil, CM before end cover welding and final CM. A description of the measurement equipment and its recent development are presented. After passing the demands set out in the specification, the results of the tests are transmitted to CERN where they are further analyzed. The paper presents the most important results of these measurements. We also report a review of the electrical non-conformities encountered e.g. interturn shorts and quench heater failure, their diagnostic and the cures

    Stakeholder perspectives on primary school pupils and sickness absence:Exploring opportunities and challenges

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    School absenteeism and its underlying causes can have negative effects on the cognitive, psychosocial and health development of a child. Research in primary education shows high rates of sickness absence. Many stakeholders are involved in addressing school absenteeism, including primary school professionals, child and youth healthcare physicians, school attendance officers and parents. This study explores these stakeholders’ perspectives, their approaches and what they envisage to be necessary in order to improve. It also aims to unveil opportunities and challenges in addressing sickness absence among primary school pupils. Qualitative research was performed with six semi-structured focus group interviews and involving 27 participants from the West-Brabant and Amsterdam regions of the Netherlands. Thematic analysis was used. The overarching theme was aiming for the child’s wellbeing. Each focus group interview started with low awareness of sickness absence as a threat to this wellbeing, but awareness grew during the interviews. The participating stakeholders regarded problematic sickness absence as complex due to a wide variety of causes, and felt that each other’s expertise was necessary to reduce sickness absence. Schools registered absence, but only occasionally used planned steps; they based the identification of problematic sickness on gut feeling rather than any agreed-upon criteria. To be able to systematically address sickness absence and thus improve the wellbeing of children, stakeholders felt the need for a clearly structured approach, including monitoring of sickness absence of all pupils, identifying problematic absence and promoting collaboration with other stakeholders. An approach should allow for tailoring solutions to the individual child

    Koppeling tussen bestrijdingsmiddelen in het oppervlaktewater en landgebruik op basis van de BasisRegistratie gewasPercelen (BRP)

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    Op de website van de Bestrijdingsmiddelenatlas (BMA) is de koppeling tussen landgebruik enerzijds en bestrijdingsmiddelen in het oppervlaktewater anderzijds een belangrijke productgroep, waarmee een mogelijke relatie tussen teelt (landgebruik) en het gebruik van bestrijdingsmiddelen kan worden onderzocht. In dit rapport wordt de BasisRegistratie gewasPercelen en CBS-bodemgebruik als nieuwe bronnen voor het landgebruik voor de koppeling onderzocht en uitgewerkt. Alleen de resultaten van de koppeling worden getoond voor de stoffen in middelen die zijn toegelaten. In dit rapport wordt de nieuwe Ctgb-API als bron hiervoor uitgewerkt. Daarnaast worden vergelijkingen gemaakt tussen oude en nieuwe bronnen en resultaten.Environmental Biolog

    The challenge of return to work in workers with cancer : employer priorities despite variation in social policies related to work and health

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    This study explored employer's perspectives on (1) their experience of good practice related to workers diagnosed with cancer and their return to work (RTW), and (2) their perceived needs necessary to achieve good practice as reported by employers from nine separate countries. Twenty-five semi-structured interviews were held in eight European countries and Israel with two to three employers typically including HR managers or line managers from both profit and non-profit organisations of different sizes and sectors. Interviews were recorded and transcribed verbatim. A grounded theory/thematic analysis approach was completed. Employers' experience with RTW assistance for workers with cancer appears to be a dynamic process. Results indicate that good practice includes six phases: (1) reacting to disclosure, (2) collecting information, (3) decision-making related to initial actions, (4) remaining in touch, (5) decision-making on RTW, and (6) follow-up. The exact details of the process are shaped by country, employer type, and worker characteristics; however, there was consistency related to the need for (1) structured procedures, (2) collaboration, (3) communication skills training, (4) information on cancer, and (5) financial resources for realizing RTW support measures. Notwithstanding variations at country, employer, and worker levels, the employers from all nine countries reported that good practice regarding RTW assistance in workers with a history of cancer consists of the six phases above. Employers indicate that they would benefit from shared collaboration and resources that support good practice for this human resource matter. Further research and development based on the six phases of employer support as a framework for a tool or strategy to support workers with a history of cancer across countries and organisations is warranted
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