66 research outputs found

    Field trial of the spatial repellency of metofluthrin-impregnated plastic strip against mosquitoes in shelters without walls (Beruga) in Lombok, Indonesia.

    Get PDF
    Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for the prevention of mosquito bites without using electricity or heat to evaporate the metofluthrin

    Sleeping arrangement and house structure affect bed net use in villages along Lake Victoria

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Although insecticide-treated bed nets are effective tools, use often does not follow ownership. House structure and space arrangements may make the attempt to use bed nets difficult, especially for school age children. The objectives of this study were to explore whether an individual's sleeping arrangements and house structure affect bed net use in villages along Lake Victoria in western Kenya.</p> <p>Methods</p> <p>Sleeping arrangements of residents were directly observed for use of a bed net, use of a bed, and location. House size, number and types of rooms, bed availability, and residents' ages were estimated. The family heads and mothers were asked about the reason for not using bed nets. Individual bed net use was examined against age and sleeping arrangement. Net use at the household level was examined against four variables: bed availability, bed net availability, house size, and number of rooms.</p> <p>Results</p> <p>Bed net use by children between five and 15 years of age was lower than that among the other age classes. However, age was dropped from the final model, and sleeping arrangement was significantly associated with net use. Net use was significantly associated with bed availability, number of rooms and their interaction.</p> <p>Conclusion</p> <p>Net use was affected by sleeping arrangement and availability of suitable locations for hanging nets, in addition to net availability. Most residents had likely not realized that sleeping arrangement was a factor in net use. The ease of hanging a net is particularly important for children.</p

    Cavitation Erosion of Titanium Alloys

    Get PDF
    Cavitation erosion was studied for various types of titanium alloys and for Ti-6 AI-4V with various heat treatments. The erosion resistance is the highest for β type alloy and decreases in order of a+β type alloy and pure titanium (a type). The resistance is macroscopically evaluated in terms of HV^2/E (HV : Vickers hardness and E : Young's modulus), but the erosion proceeds depending on the microstructures. Heat treatments changes the microstructure of Ti-6 AI-4V drastically. Therefore, annealing at high temperature produces the large second phase and results in the accerelation of the erosion depth, in spite of low mass loss rate

    Leukotriene E4–induced pulmonary inflammation is mediated by the P2Y12 receptor

    Get PDF
    Of the potent lipid inflammatory mediators comprising the cysteinyl leukotrienes (LTs; LTC4, LTD4, and LTE4), only LTE4 is stable and abundant in vivo. Although LTE4 shows negligible activity at the type 1 and 2 receptors for cys-LTs (CysLT1R and CysLT2R), it is a powerful inducer of mucosal eosinophilia and airway hyperresponsiveness in humans with asthma. We show that the adenosine diphosphate (ADP)–reactive purinergic (P2Y12) receptor is required for LTE4-mediated pulmonary inflammation. P2Y12 receptor expression permits LTE4 -induced activation of extracellular signal-regulated kinase in Chinese hamster ovary cells and permits chemokine and prostaglandin D2 production by LAD2 cells, a human mast cell line. P2Y12 receptor expression by LAD2 cells is required for competition between radiolabeled ADP and unlabeled LTE4 but not for direct binding of LTE4, suggesting that P2Y12 complexes with another receptor to recognize LTE4. Administration of LTE4 to the airways of sensitized mice potentiates eosinophilia, goblet cell metaplasia, and expression of interleukin-13 in response to low-dose aerosolized allergen. These responses persist in mice lacking both CysLT1R and CysLT2R but not in mice lacking P2Y12 receptors. The effects of LTE4 on P2Y12 in the airway were abrogated by platelet depletion. Thus, the P2Y12 receptor is required for proinflammatory actions of the stable abundant mediator LTE4 and is a novel potential therapeutic target for asthma

    Automated Workflow for Preparation of cDNA for Cap Analysis of Gene Expression on a Single Molecule Sequencer

    Get PDF
    Background: Cap analysis of gene expression (CAGE) is a 59 sequence tag technology to globally determine transcriptional starting sites in the genome and their expression levels and has most recently been adapted to the HeliScope single molecule sequencer. Despite significant simplifications in the CAGE protocol, it has until now been a labour intensive protocol. Methodology: In this study we set out to adapt the protocol to a robotic workflow, which would increase throughput and reduce handling. The automated CAGE cDNA preparation system we present here can prepare 96 ‘HeliScope ready ’ CAGE cDNA libraries in 8 days, as opposed to 6 weeks by a manual operator.We compare the results obtained using the same RNA in manual libraries and across multiple automation batches to assess reproducibility. Conclusions: We show that the sequencing was highly reproducible and comparable to manual libraries with an 8 fold increase in productivity. The automated CAGE cDNA preparation system can prepare 96 CAGE sequencing samples simultaneously. Finally we discuss how the system could be used for CAGE on Illumina/SOLiD platforms, RNA-seq and fulllengt

    Multimodal pyrethroid resistance in malaria vectors, Anopheles gambiae s.s., Anopheles arabiensis, and Anopheles funestus s.s. in western Kenya.

    Get PDF
    Anopheles gambiae s.s., Anopheles arabiensis, and Anopheles funestus s.s. are the most important species for malaria transmission. Pyrethroid resistance of these vector mosquitoes is one of the main obstacles against effective vector control. The objective of the present study was to monitor the pyrethroid susceptibility in the 3 major malaria vectors in a highly malaria endemic area in western Kenya and to elucidate the mechanisms of pyrethroid resistance in these species. Gembe East and West, Mbita Division, and 4 main western islands in the Suba district of the Nyanza province in western Kenya were used as the study area. Larval and adult collection and bioassay were conducted, as well as the detection of point mutation in the voltage-gated sodium channel (1014L) by using direct DNA sequencing. A high level of pyrethroid resistance caused by the high frequency of point mutations (L1014S) was detected in An. gambiae s.s. In contrast, P450-related pyrethroid resistance seemed to be widespread in both An. arabiensis and An. funestus s.s. Not a single L1014S mutation was detected in these 2 species. A lack of cross-resistance between DDT and permethrin was also found in An. arabiensis and An. funestus s.s., while An. gambiae s.s. was resistant to both insecticides. It is noteworthy that the above species in the same area are found to be resistant to pyrethroids by their unique resistance mechanisms. Furthermore, it is interesting that 2 different resistance mechanisms have developed in the 2 sibling species in the same area individually. The cross resistance between permethrin and DDT in An. gambiae s.s. may be attributed to the high frequency of kdr mutation, which might be selected by the frequent exposure to ITNs. Similarly, the metabolic pyrethroid resistance in An. arabiensis and An. funestus s.s. is thought to develop without strong selection by DDT

    A newly developed snow vehicle (SM100S) for Antarctica IV. Low temperature properties of crawler belt

    No full text
    In order to discover a high cold-resistance material for use in the crawler belt of snow vehicles, the physical properties at very low temperatures of a recently developed material, isoprene/butadiene (70/30) random copolymer filled with carbon black, was investigated in comparison with a blended rubber NR/BR (65/35) as well as a currently used NR. It has been found that this material can keep rubber elasticity even at low temperatures blow -70℃, though it is somewhat inferior to the other two materials as to strengths such as stress-at-break and tear; and hence, it is considered as quite worthy of a practical test under equipped for a snow vehicle in the Antarctic area

    Field trial of the spatial repellency of metofluthrin-impregnated plastic strip against mosquitoes in shelters without walls (Beruga) in Lombok, Indonesia.

    Get PDF
    Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for the prevention of mosquito bites without using electricity or heat to evaporate the metofluthrin

    ナンキョク オオガタ セツジョウシャ (SM100S) ノ カイハツ IV. ゴム リタイ ノ テイオン トクセイ

    Get PDF
    耐超低温特性の観点から, 最近開発されたイソプレン・ブタジエン共重合体の雪上車用履帯ゴムとしての実用の可否を現行の天然ゴムのみの系と天然ゴム/ブタジエンゴムのブレンド系との比較において検討した。その結果, 強度的にはこれら二者より劣るが, -70℃においても十分なゴム弾性を保持しており, 実用試験をしてみる価値があることがわかった。In order to discover a high cold-resistance material for use in the crawler belt of snow vehicles, the physical properties at very low temperatures of a recently developed material, isoprene/butadiene (70/30) random copolymer filled with carbon black, was investigated in comparison with a blended rubber NR/BR (65/35) as well as a currently used NR. It has been found that this material can keep rubber elasticity even at low temperatures blow -70℃, though it is somewhat inferior to the other two materials as to strengths such as stress-at-break and tear; and hence, it is considered as quite worthy of a practical test under equipped for a snow vehicle in the Antarctic area
    corecore