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Trapping mosquitoes using milk products as odour baits in western Kenya
Eunice A Owino
Parasites & Vectors , 2010, DOI: 10.1186/1756-3305-3-55
Abstract: Comparative efficacy studies were carried out in the field using Latin square experimental designs. In the first study, a counterflow geometry (CFG) trap (MM-x model; American Biophysics Corp., USA.) baited with Limburger cheese, man landing catches (MLC), Centres for Disease Control (CDC) light trap and an entry trap were compared. In the second study, three CFG traps baited with either Limburger cheese, African traditional milk cream or with no bait were compared and in the third study four CDC traps baited with either Limburger cheese, African traditional milk cream, light or with no bait were compared. Parameters like species, catch size, abdominal status, parity status and size of the collected mosquitoes were compared.A total of 1,806 mosquitoes were collected (60% An. gambiae s.l and 25% An.funestus, culicines 15%). There was no significant difference in the number of An. funestus trapped by the CFG trap baited with Limburger cheese from those trapped by the MLC (P = 0.351). The Limburger cheese baited CFG trap collected significantly more gravid An. funestus than the MLC (P = 0.022). Furthermore, when the CFG trap baited with Limburger cheese and the CFG trap baited with milk cream were compared, there was no significant difference in the number of An. funestus collected (P = 0.573). The same trend was observed in the comparison of Limburger cheese baited CDC trap and milk cream baited CDC trap.Limburger cheese and African traditional milk cream have a potential as effective odour baits for sampling/surveillance and as oviposition attractants for the malaria vector, Anopheles funestus.Ample evidence has shown that host-seeking female mosquitoes mainly locate their hosts by odours produced by the hosts [1-5]. It could, therefore, be useful if traps baited with host odours would lure mosquitoes as strongly as normal healthy humans [5] or even lure more mosquitoes than healthy human beings [6]. Such traps could then be used in the trapping of mosquitoes in larg
Anopheles gambiae s.s. breeding in polluted water bodies in urban Lagos, southwestern Nigeria  [PDF]
T.S. Awolola, A.O. Oduola, J.B. Obansa, N.J. Chukwurar & J.P. Unyimadu
Journal of Vector Borne Diseases , 2007,
Abstract: Background & objective: Urban malaria is on the rise in Nigeria due to rapid industrialisation anddevelopmental activities. A study was undertaken in Lagos, Nigeria to study the Anopheles breedingin polluted water bodies.Methods: Anopheles larval breeding habitats were surveyed and water samples from 24 larval breedingsites from four strategic areas in urban Lagos were analysed. The relationship between eight abioticvariables (pH, dissolved oxygen, conductivity, hardness, nitrate, total dissolved solids, turbidity andoil) and density of Anopheles larvae were investigated. The levels of heavy metals (Zn, Co, Cu, Pb,Mn, Fe, Hg and Ni) pollution were analysed by Atomic Absorption Spectrophotometry.Results: Morphological and PCR analysis of 2358 anopheline larvae revealed only the presence oftwo members of the Anopheles gambiae complex consisting of 93.1% Anopheles gambiae s.s. and6.9% An. arabiensis. Multiple regression analysis revealed a significant association betweenoccurrence of An. arabiensis larvae and two independent variables: pH and turbidity but not for An.gambiae s.s. The levels of three heavy metals: Fe, Cu and Pb from more than half of the sites surveyedwere three times higher than the values obtained in natural breeding sites of An. gambiae s.s. from arural area of Lagos. Over 85% of An. gambiae s.s. larvae were found in water bodies characterisedby low dissolved oxygen (<3 mg/L), high conductivity (>900 uS/cm), turbidity (>180 FAU), oil(>11 mg/L) and heavy metals: Fe, Cu, and Pb (>0.4 mg/L).Interpretation & conclusion: These results indicate that An. gambiae s.s. is adapting to a wide rangeof water pollution in this urban area. The survival of the mosquito in widespread polluted waterbodies across Lagos metropolis could be responsible for the rise in the incidence of malaria.
Fibre Bragg Gratings Inscribed in Homemade Microstructured Fibres
JIN Long,KAI Gui-Yun,LI Jin-Yan,CHEN Wei,LIU Jian-Guo,LIU Yan-Ge,WANG Zhi,ZHANG Jian,LIU Bo,YUAN Shu-Zhong,DONG Xiao-Yi,
金龙
,开桂云,李进延,陈伟,刘建国,刘艳格,王志,张键,刘波,袁树忠,董孝义

中国物理快报 , 2007,
Abstract: Fibre Bragg gratings (FBGs) are inscribed in homemade microstructured fibres by the standard phase mask method. Enhanced couplings between the forward fundamental mode and backward cladding modes are obtained.The mode coupling and spectral characteristics are investigated experimentally. The cladding mode resonances can be affected by fillingactive materials into the air holes, which will be useful for the implementation of tunable photonic devices in optical fibre communication and sensing systems.
Toxicity of fruit fly baits to beneficial insects in citrus
J.P. Michaud
Journal of Insect Science , 2003,
Abstract: Two fruit fly baits, Nu-Lure /malathion and GF-120 (Spinosad ) were evaluated in the laboratory for non-target impacts on beneficial insects. Nu-Lure/malathion proved attractive and toxic to adults and larvae of the coccinellid species, Curinus coeruleus Mulsant, Cycloneda sanguinea L. and Harmonia axyridis Pallas, a lacewing species, Chrysoperla rufilabris Burmeister. The coccinellids Olla v-nigrum Mulsant, Scymnus sp. and nymphs of the insidious flower bug, Orius insidiosus (Say) did not succumb to Nu-Lure baits, even in no-choice situations. Nu-Lure was also attractive and lethal to adults of two aphidophagous flies; Leucopis sp. and the syrphid fly Pseudodorus clavatus (F.). Both Nu-Lure and GF-120 caused significant mortality to the parasitoid wasps, Aphytis melinus De Bach and Lysiphlebus testaceipes Cresson, within 24 h of exposure. However, GF-120 caused no significant mortality to any coccinellid in either choice or no-choice situations, despite considerable consumption of baits. Adults of P. clavatus tended to avoid GF-120, although mortality was significant in no-choice tests. Although larvae and adults of the lacewing C. rufilabris consumed GF-120, mortality was delayed; adults died 48 -96 h post-exposure and those exposed as larvae died two weeks later in the pupal stage. The Nu-Lure bait did not appear palatable to any of the insects, but the high concentration of malathion (195,000 ppm) caused rapid mortality to susceptible insects. Nu-Lure bait without malathion also caused significant mortality to flies and lacewings in cage trials. Although GF-120 bait appeared more benign overall, further research efforts are warranted to increase its selectivity for target fly species and reduce its attractiveness to parasitoids and lacewings. I conclude that the Florida "fly free zone" protocol in its current form is not compatible with an IPM approach to commercial citrus production.
Oviposition deterrence induced by Ocimum kilimandscharicum and Ocimum suave extracts to gravid Anopheles gambiae s.s (Diptera: Culicidae) in laboratory
Kweka Eliningaya,Lyatuu Ester,Mboya Michael,Mwang′onde Beda
Journal of Global Infectious Diseases , 2010,
Abstract: Background: In most of the past decades, mosquito control has been done by the use of indoor residual spray and insecticides-treated bed nets. The control of mosquitoes by targeting the breeding sites (larval habitat) has not been given priority. Disrupting the oviposition sensory detection of mosquitoes by introducing deterrents of plant origin, which are cheap resources, might be add value to integrated vector control. Such knowledge is required in order to successfully manipulate the behavior of mosquitoes for monitoring or control. Materials and Methods: Twenty gravid mosquitoes were placed in a cage measuring 30 Χ 30 Χ 30 cm for oviposition. The oviposition media were made of different materials. Experiments were set up at 6:00 pm, and eggs were collected for counting at 7:30 am. Mosquitoes were observed until they died. The comparisons of the number of eggs were made between the different treatments. Results: There was significant difference in the number of eggs found in control cups when compared with the number of eggs found in water treated with Ocimum kilimandscharicum (OK) (P=0.02) or Ocimum suave (OS) (P=0.000) and that found in water with debris treated with OK (P=0.011) or OS (P=0.002). There was no significant difference in the number of eggs laid in treated water and the number of eggs laid in water with debris treated either with OK (P=0.105) or OS (P=0.176). Oviposition activity index for both OS and OK experiments lay in a negative side and ranged from 0.19% to 1%. The results show that OS and OK deter oviposition in An.gambiae s.s. Conclusions: Further research needs to be done on the effect of secondary metabolites of these plant extracts as they decompose in the breeding sites. In the event of favorable results, the potential of these plant extracts can be harnessed on a larger scale.
Simple homemade apparatus for harvesting uncultured magnetotactic microorganisms
Lins, Ulysses;Freitas, Flavia;Keim, Carolina Neumann;Barros, Henrique Lins de;Esquivel, Darci Motta S.;Farina, Marcos;
Brazilian Journal of Microbiology , 2003, DOI: 10.1590/S1517-83822003000200004
Abstract: a simple apparatus for harvesting uncultured magnetotactic microorganisms is described. this apparatus consists of a glass container with two openings. a large opening on the topside is used to introduce the sediment and water. the sediment and water are previously stored in loosely capped bottles previously tested for the presence of magnetotactic bacteria. the apparatus is exposed to a properly aligned magnetic field of a homemade coil and the bacteria are removed through the capillary end of the second opening of the container. harvested bacteria can then be used to ultrastrucutral studies using electron spectroscopic imaging. large numbers of magnetotactic bacteria consisting of cocci and rod-shaped cells were efficiently collected from different environments. this apparatus is useful for microbiological studies on uncultured magnetotactic bacteria, especially in molecular approaches for phylogenetic investigations that give information on the natural diversity of microbial communities.
Simple homemade apparatus for harvesting uncultured magnetotactic microorganisms  [cached]
Lins Ulysses,Freitas Flavia,Keim Carolina Neumann,Barros Henrique Lins de
Brazilian Journal of Microbiology , 2003,
Abstract: A simple apparatus for harvesting uncultured magnetotactic microorganisms is described. This apparatus consists of a glass container with two openings. A large opening on the topside is used to introduce the sediment and water. The sediment and water are previously stored in loosely capped bottles previously tested for the presence of magnetotactic bacteria. The apparatus is exposed to a properly aligned magnetic field of a homemade coil and the bacteria are removed through the capillary end of the second opening of the container. Harvested bacteria can then be used to ultrastrucutral studies using electron spectroscopic imaging. Large numbers of magnetotactic bacteria consisting of cocci and rod-shaped cells were efficiently collected from different environments. This apparatus is useful for microbiological studies on uncultured magnetotactic bacteria, especially in molecular approaches for phylogenetic investigations that give information on the natural diversity of microbial communities.
Rapid Elimination of German Cockroach, Blatella germanica, by Fipronil and Imidacloprid Gel Baits
H Nasirian
Iranian Journal of Arthropod-Borne Diseases , 2008,
Abstract: Background: Baits have become popular and effective formulations against urban insect pests. Compared with re-sidual sprays toxic gel baits are used more and more frequently to control urban cockroach populations. The aim of this study was to investigate the usage of two commercially available fipronil and imidacloprid gel bait formulations against Blattella germanica field infested in Iran. Methods: The study was carried out in an urban area at Tehran from March 2004 to September 2005. The 0.05% fipronil and 2.15% imidacloprid gel baits were placed continuously in 3 residential German cockroach infested units. Pre- and post-treatment cockroach density was assessed by visual count method. Results: Pre- and post-treatment visual count of cockroaches in treatment and control areas, and percentage reduc-tion in cockroach density in treatment areas in comparison to control areas was showed that density reduction was increased with the 0.05% fipronil and 2.15% imidacloprid gel baits in treated areas from 1st to 9th week in compari-son to control area. After 60 days, German cockroaches eliminated completely from these areas. Conclusion: These results show that fipronil and imidacloprid gel baits are highly effective in field German cock-roach infested after insecticide spraying control failure German cockroach infested fields where spraying of pyrethroid insecticides failed to control the situation and confirm previous reports stating that avermectin and hydramethylnon are more effective than conventional insecticides in baits against cockroaches. Therefore, fipronil and imidacloprid gel baits are appropriate candidates for controlling German cockroach infested dwellings in Iran where control with other insectices failed because of resistance.
ANEWSPECIESOFTHEGENUSTOMOCERUS(S.S.)(COLLEMBOLA:TOMOCERIDAE)FROMCHINA  [PDF]
昆虫分类学报 , 1997,
Abstract: 本文记述了鳞?属华东地区1新种――近似鳞?Tomocerus(s.s.)similis,sp.nov.。本新种和克洛鳞?T.(s.s.)kinoshitaiYosi,1954非常相似,但可从小爪内齿、头部毛序及弹器齿节上棘状刚毛等特征相区别。正模♀,江苏滁县琅琊山,1990-IV-8,8040;副模:1♀,同正模;安徽黄山:1♂,2♀♀,1990-VI-3,8164、8169和8172;2♀♀,1990-VI-16,8222;1♀,1993-IX-12,8344;江苏:1♂,句容县宝华山,1990-V-28,8125;1♀,南京紫金山,1994-IV-9,8355;1♀,灌云县,1995-I,8437。模式标本保存于南京大学生物系。
Homemade Experimental Platform Used in Major Course Experiment Class
Minming Gu,Haipeng Pan
Education Research Frontier , 2012,
Abstract: This paper discusses the effect of homemade experiment instrument in the laboratory construction and the experimental teaching reform. Firstly this paper analyzes the necessity and feasibility of the homemade experiment platform. Then taking embedded motor control experimental platform as an example, it introduces the operation of the Institute of automation, whose teachers combine scientific research with practical teaching and turn the achievements into laboratory construction and students' practical teaching to initiative the students’ study interest. By changing the teaching concept, introducing new teaching mode, improving the experimental approaches and combing with the basic theory of embedded motor control, theory teaching and experimental teaching are integrated organically via the homemade experiment platform. Thus, students can better master the relevant knowledge of motor control, and their innovation ability and comprehensive abilities can be strengthened.
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