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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Olfactory response of Lygus hesperus Knight to chemicals naturally found in alfalfa

Zaugg, Jerry Lynn, 1942- January 1971 (has links)
No description available.
32

Miško želdinių ir žėlinių būklė ir apsauga VĮ Kauno miškų urėdijoje / Protection of artificial and natural afforestation in Kaunas State Forest Enterprise

Kovalčikas, Edmundas 21 June 2010 (has links)
2008 metais Kauno miškų urėdijoje atkurta 236,8 ha miško želdinių ir žėlinių, o apsaugota repelentais 97,8 ha. Iš to galima spręsti, kad nevisi miško želdiniai ir žėliniai yra apsaugoti nuo neigiamo elninių žvėrių poveikio. Apdoroti repelentais miško želdiniai ir žėliniai sudaro 41 % nuo visų įveistų miško želdinių ir žėlinių. Dar 8,7% miško želdinių ir žėlinių buvo apsaugota panaudojant tvoras, taip pat apie 2% panaudojant individualias apsaugos priemones. Iš to galima spręsti, kad buvo įveista 236,8 ha miško želdinių ir žėlinių, iš kurių 56,9% buvo apsaugota įvairiomis apsaugos priemonėmis nuo neigiamo elninių žvėrių poveikio. 2009 metais Kauno miškų urėdijoje atkurta 201,6 ha miško želdinių ir žėlinių, o apdorota repelentais 115,2 ha. Tai sudaro 57,1% nuo visų įveistų miško želdinių ir žėlinių ploto ir palyginus su ankstesniais metais galima spręsti jog jaunuolynų apsauga nuo elninių žvėrių padidėjo. Tuo pačiu 6,6% miško želdinių nuo bendro atkurtų želdinių ploto buvo apsaugota panaudojant vielos tinklą ir 2,9% miško želdinių ir žėlinių apsaugota panaudojant individualias apsaugos priemones. 2009 metais Kauno miškų urėdijoje įveista 201,6 ha miško želdinių ir žėlinių iš kurių 73,6 % apsaugota įvairiomis apsaugos priemonėmis nuo neigiamo elninių žvėrių poveikio. / In 2008 there were afforested 236,8 ha of forest land Kaunas State Forest Enterprise, both naturally and artificially. Among them 97,8 ha were covered by repellents. This shows, that not all artificially and naturally afforested plots were protected from negative impact of deer animals. Covered by repellents plots compose 41% from all afforested plots. Another 8,7% of afforested plots were fenced, yet 2% were protected by using of individual protective measures. This shows, that out of total afforested area (236,8 ha), 56,9% were protected by using different protective measures to avoid negative impact, caused by deer species. In 2009 there were afforested 201,6 ha of forest land Kaunas State Forest Enterprise, both naturally and artificially. Among them only 115,2 ha were covered by repellents. It compose 57,1% of all afforested areas. Comparing this with previous years, conclusion could be made, that protection from browsing and striping of young stands has increased. As well 6,6% of total afforested area were fenced, and 2,9% were protected by using individual protective measures. In total there were afforested 201,6 ha in Kaunas State Forest Enterprise during 2009, 73,6% of them were protected by using different protective measures to avoid negative impact, caused by deer animals.
33

Native plants as repellents against malaria mosquitoes : ethnobotanical, behavioural & electrophysiological studies /

Waka, Maedot. January 2005 (has links)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
34

Avaliação da atividade de formulações comerciais de repelentes sobre mosquitos Aedes aegypti (Diptera - Culicidae) / Evaluation of the activity of commercial formulations of mosquito repellents Aedes aegypti (Diptera - Culicidae)

Estevam, Adriana dos Santos 18 June 2018 (has links)
Objectives: To evaluate the efficacy of commercially used insect repellents against Aedes aegypti stings. Material and Methods: Was used method standard the World Health Organization to evaluate the sensitivity of the mosquito by estimating the total protection time (TPT) of the repellent. The test consists of application of the product and introduction of the volunteer arm into cages containing 50 female mosquitoes, aged between five and seven days. The initial product was 10% technical grade N, N diethylbenzamine (DEET) and four formulations with different concentrations of DEET, OFF Family (7,125%), Baruel (9,5%), Expert Total : 1612043 and 16144314, Super Repelex Aerosol (11%), product based on IR3535 (Repeden Spray 12%, Jonsons Baby Lotion 12.5%), and the ICARIDINE base (Exposis Extreme Tetra 25%), by the median of each product in 6 volunteers, being three men and three women. Results: The OFF Family brand (DEET 7,125%), Baruel (DEET 9,5) and analytical DEET (10%) demonstrated a median of 30 minutes, even presenting different concentrations; Super Repelex Aerosol (DEET 11%) among the products containing DEET was the one that presented a higher median, with a TPT of 90 minutes; Expert Total (DEET 15%) (1st batch) and Expert Total (DEET 15%) (2nd batch) are shown with medians equal with a time of 60 minutes; Repeden Spray (IR3535 12%) and Johnsons baby (IR3535 12.5%) presented a median TPT of 60 and 30 minutes respectively, differing only in the degree of concentration of the active principle; Exposis Extreme (25% Icaridina) presented a median of 120 minutes, showing a superiority in relation to the other products. Conclusion: The products had a complete protection time lower than the one specified in their labels, and may leave the population that use them as a control measure against several unprotected diseases, requiring a greater number of reapplications of the products. / Objetivos: Avaliar a eficácia de repelentes utilizados comercialmente contra picadas de Aedes aegypti. Material e Métodos: Foi utilizado o método padrão da Organização Mundial da Saúde para avaliar a sensibilidade do mosquito através da estimativa de tempo de proteção completa (TPC) do repelente. O teste consiste na aplicação do produto e introdução do braço de voluntário em gaiolas contendo 50 mosquitos fêmeas, com idade entre cinco a sete dias. Foi avaliado inicialmente produto a base de N,N dietilbenzamina (DEET) grau técnico a 10% e quatro formulações com diferentes concentrações de DEET, OFF Family (7,125%), Baruel (9,5%), Expert Total (15%) lotes: 1612043 e 16144314, Super Repelex Aerossol (11%), produto a base de IR3535 (Repeden Spray 12%, Loção Jonsons Baby 12,5%,) e a base de ICARIDINA (Exposis Extreme Tetra 25%), e estimado o TPC pela mediana de cada produto em 6 voluntários, sendo três homens e três mulheres. Resultados: A marca OFF Family (DEET 7,125%), Baruel (DEET 9,5) e DEET analítico (10%) demostraram uma mediana de 30 minutos, mesmo apresentando diferentes concentrações; Super Repelex Aerossol (DEET a 11%), dentre os produtos contendo DEET, foi o que apresentou uma maior mediana, com TPC de 90 minutos; Expert total (DEET 15%) (1º lote) e o Expert Total (DEET 15%) (2º lote) mostram-se com medianas iguais com um tempo de 60 minutos; Repeden Spray (IR3535 12%) e Johnsons baby (IR3535 12,5%) apresentaram uma mediana com TPC de 60 e 30 minutos respectivamente, diferindo apenas no grau da concentração do princípio ativo; Exposis Extreme (Icaridina a 25%) apresentou uma mediana de 120 minutos, mostrando uma superioridade em relação aos outros produtos. Conclusão: Os produtos apresentaram tempo de proteção completa inferior a especificada em seus rótulos, podendo deixar a população que os utilizam como medida de controle contra diversas doenças desprotegida, sendo necessário maior número de reaplicações dos produtos para atingir a o período de proteção desejado. / São Cristóvão, SE
35

An integrated subterranean termite management system coupling soil amendments with insect repellent plant tissues

Kitchens, Shane Clinton 03 May 2008 (has links)
Currently, soil termiticides are the primary termite defense mechanism used under and around living spaces in the continental United States. While this form of treatment has been effective for many years, the creation of a new, more environmentally friendly termite management system could reduce the amount of termiticides introduced annually into the environment around structures. A natural barrier containing soil amendments and mulches amended with insect-repellent plant tissues discourages termite foraging and directs the termites away from the structure. The proposed integrated management system developed during this project, divides a structure into three zones. Each zone has particular responsibilities to the overall biological durability of the structure. This study concentrates on the inner-detritus zone, which extends 24” (0.61m) from the outer wall of the structure, an area that can harbor potential hazards such as moisture traps, conducive termite food, water and protection sources, and other factors that could put undue biological pressures on the structure. Altering this zone, more specifically the pH of the soil and the mixture of products used as mulch, creates an environment unsuitable for termite foraging. This integration of several termite repelling strategies should obviate or significantly reduce the need for termiticidal soil barriers under and around houses.
36

The water-repellent treatment of cotton fabrics with organo chlorosilanes

Deane, Talbert S. January 1947 (has links)
The use of methylchlorosilanes as an agent to produce water-repellent characteristics in cotton fabrics was patented by W.I. Patnode of the General Electric Company. Since very little information has been published on the process, this investigation was undertaken to determine the optimum conditions for treating cotton fabric. Experimental tests were made using 10 inch square samples of three different poplin type cotton fabrics dried to constant weight in a vacuum dryer and over P₂O₅ in a desiccator. Each cotton sample was treated with one of five different organo chlorosilanes or a mixture of methyltrichlorosilane and dimethyldichlorosilane. The time of contact between the fabric and silane was established at 60 seconds by a number of preliminary tests. Room temperature of approximately 30°C and pressure of approximately 710 mm were arbitrarily chosen for the reaction. The tests were made with the fabric in a three liter distilling apparatus and the required amount of silane for the volume concentration desired was vaporized and transported into the reactor by a difference in pressure of the vaporizer and reaction vessel. Fabric samples were supported in the reactor over a glass distributor ring which disbursed the silane. Volume concentrations of silanes of 0.1, 0.5, 1.0, and 5.0 percent were used in the investigation. Neutralization of end products was attempted with a 10 minute dried-air wash, 13-16 percent volume concentration of ammonia and five percent solution of sodium acetate. Data on results of tests on end products indicated the following conclusions: 1. Neutralization of end products is necessary to prevent deterioration of the fabric, as indicated by a maximum reduction in tensile strength of 80 percent as compared to an untreated sample. 2. The 60 second time of silane-fabric contact is sufficient to produce a water-repellent fabric. 3. Fabrics treated with a one percent volume concentration of mixtures of methyltrichlorosilane and dimethyldichlorosilane show a spray test rating of 90 as compared to a rating of 70-80 for fabrics treated with individual silanes. 4. Standard methods of testing treated fabrics do not indicate the hygienic properties of the treated fabrics. / Master of Science
37

The odor components of the defense mechanism of the "green worm", Amynthas hupeiensis and wheat insect repellent in bay leaves, (Laurus nobilis, L.)

Saim, Norashikin. January 1985 (has links)
Call number: LD2668 .T4 1985 S245 / Master of Science
38

Physico-chemical characterization of African traditional cosmetics produced by the Ovahimba tribes of Northern Namibia

Molefe, Ontibile January 2015 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2015. / Ovahimba people from Kunene region, northern Namibia, are known for covering their bodies with red ochre mixed with clarified butterfat, traditionally known as otjize to give them a distinct red appearance. Ochre refers to a clay-like earth pigment which contains some form of iron-containing mineral. A mixture of traditional herbs with clarified butterfat, otjizumba, is also applied around the necks as a perfume. This study was prompted by ethnographic interviews amongst the Ovahimba people which revealed functional uses of the traditional cosmetics, specifically the red ochre-derived cosmetic, as a mosquito repellent. Several analytical techniques were used to determine the presence of mosquito repellent compounds in the red ochre- derived cosmetic and the aromatic plant derived-cosmetic. GC-MS was used to identify the presence of compounds which have previously been found to have mosquito repellent capabilities. GC-MS analysis identified mostly oxygenated compounds which include ketones (2-dodecanone, 2-nanonone, 2-undecanone and 2-tridecanone), aldehydes (heptanal and nonanal) and carboxylic acids (hexanoic acid and heptanoic acid) in dichloromethane extracts of otjize and mostly hydrocarbons (o-cymene, α-pinene, limonene, and squalene) and less oxygenated compounds (terpinen-4-ol and α-campholenal) in plant derived cosmetic extracts. The chemical composition of the cosmetics was also analyzed using FTIR. FTIR analysis for organics in both cosmetics showed presence of vibrational motions including O-H, C=O, C-H, C=C and C-C which affirmed the presence of organic functional groups including aldehydes, ketones, esters, alkenes and alkanes. Peak patterns observed using GC-FID showed that the mixture of red ochre and clarified butterfat released higher quantities of volatiles than when individual samples were analyzed. Mineralogical composition of red ochre was determined by PXRD, supported by FTIR which revealed as significant amount of hematite (Fe2O3), the primary mineral responsible for the red hue of the ochre. Other major minerals including quartz (SiO2), kaolinite (Al2(Si2O5)(OH)4, calcites (CaCO3) and chalconatronite(Na2Cu(CO3)2.3H2O) were found to be present in the ochre powder. Elemental analysis of the ochre determined using EDXRF and ICP-OES supported mineralogical composition as iii Ovahimba red ochre exhibited high content of iron (Fe) and silicon (Si) and a significant amount of aluminum (Al), calcium (Ca) and copper (Cu). Based on % weight, presence of transition metals in red ochre powder identified using ICP-OES was observed in the descending order; Fe> V> Cu> Au> Ti> Zr. Based on the analysis carried out in this study, it is suggested that red ochre provides catalytic role, due to its diverse metal content especially the presence of transition metals including Fe and Cu, which might be influencing the production of secondary products during autoxidation of fatty acids present in otjize, specifically ketones and aldehydes. It was also concluded that the composition of clarified butterfat could be attributed to the release of mosquito repellent compounds in the red ochre derived cosmetic because when animal fat (kudufat) was used as an organic binder, the mixture did not release any of the identified possible mosquito repellent compounds. Keywords: Aldehydes, autoxidation, clarified butterfat, fatty acids, ketones, mosquito repellents, and red ochre
39

Uso de compostos repelentes produzidos por cães resistentes ao Rhipicephalus sanguineus sensu lato para o seu controle em cães susceptiveis / Use of repellent compounds produced by dogs resisting to Rhipicephalus sanguineus sensu lato for its control in susceptiple dogs

Oliveira Filho, Jaires Gomes de 21 February 2018 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-02-28T16:12:09Z No. of bitstreams: 2 Tese - Jaires Gomes de Oliveira Filho - 2018.pdf: 1814554 bytes, checksum: 3897a940820688b6672b09b6a409c4b8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-02-28T16:12:35Z (GMT) No. of bitstreams: 2 Tese - Jaires Gomes de Oliveira Filho - 2018.pdf: 1814554 bytes, checksum: 3897a940820688b6672b09b6a409c4b8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-28T16:12:35Z (GMT). No. of bitstreams: 2 Tese - Jaires Gomes de Oliveira Filho - 2018.pdf: 1814554 bytes, checksum: 3897a940820688b6672b09b6a409c4b8 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Rhipicephalus sanguineus sensu lato, the "brown dog tick", preferentially parasite the domestic dog, in the latter can parasite others mammals species including humans. This tick demonstrates a hunting behavior by its host, being widely attracted by the bark and the CO2 among other signs related to the presence of its hosts. Despite being commonly found parasite on dogs, it is known that some breeds such as beagles are less parasitic than other breeds like English Cocker Spaniel which can present a parasitic load about up to 11.5 times higher than mongrel dogs. It is notable a capacity of ticks and other arthropods in their hosts in relation to desirable or undesirable characteristics that can perceive these by means of chemoreception of volatile compounds emanated by these hosts. This adaptive tool is called olfactory aposematism. Olfactory apostotism is capable of an ectoparasite in avoiding its hosts through a perception of a volatile chemical emanated by it that signals a negative adaptive response to the arthropod. Usually this response may be linked to immune factors, excessive grooming, inaccessibility or other factors. One of the big problems nowadays undoubtedly is the control of ticks and diseases that are transmitted to their hosts during the blood repast. One of the alternatives for control of parasitism in order to deter ticks from the search for their hosts is a use of compounds found in resistant hosts that are interpreted by these arthropods as non-hosts. These compounds demonstrate a more specific activity between arthropod parasites and their hosts, since they were selected during an adaptation between species involved in this parasite-host relationship forging bases of parasite selection by susceptible and resistant hosts. / Rhipicephalus sanguineus sensu lato, também conhecido como “carrapato marrom do cão”, parasita preferencialmente o cão doméstico, no entanto pode parasitar inúmeras outras espécies mamíferas inclusive seres humanos. Este carrapato demonstra um comportamento de busca ativa por seu hospedeiro, sendo amplamente atraído pelo latido e pelo CO2 e outros sinais relacionados a presença de seus hospedeiros. Apesar de parasitar preferencialmente cães sabe-se que algumas raças como o beagle são menos parasitadas que outras raças como Cocker spaniel inglês que podem apresentar uma carga parasitaria cerca de até 11,5 vezes maior que cães mestiços. É notável a capacidade de carrapatos e demais artrópodes tem em selecionar seus hospedeiros em relação a características desejáveis ou indesejáveis que conseguem perceber destes, por meio da quimiorrecepção de compostos voláteis emanados pelos hospedeiros. A esta ferramenta adaptativa damos o nome aposematismo olfativo que é capacidade de um de parasito em evitar seus hospedeiros mediante a percepção de um químico emanado por este que sinalize uma resposta adaptava negativa ao artrópode. Geralmente esta resposta pode estar ligada a fatores imunes, excesso de grooming ou inacessibilidade ou demais fatores. Um dos grandes problemas na atualidade sem dúvida e o controle de carrapatos e doenças que são transmitem a seus hospedeiros durante o repasto sanguíneo. Uma das alternativas para o controle de parasitismo afim de dissuadir os carrapatos da busca por seus hospedeiros é uma utilização de compostos encontrados em hospedeiros resistentes que são interpretados por estes artrópodes como não hospedeiros. Estes compostos demonstram atividade mais especifica entre artrópode parasitos e seus hospedeiros, pois foram selecionados durante uma adaptação entre espécies envolvidas nesta relação parasitohospedeiro forjando bases da seleção de parasitos por hospedeiros suscetíveis e resistentes.
40

Réactivité des polyéthers ionophores et des coumarines : vers des systèmes moléculaires efficaces pour la santé animale / Chemical reactivity of polyether ionophores and coumarins : towards effective molecular systems for animal health

Vialle, Émilie 22 September 2011 (has links)
L’objectif de cette thèse, réalisée en collaboration avec la société Mérial, concerne la santé animale et s’oriente vers la synthèse de molécules actives à visée préventive ou thérapeutique. Deux sujets distincts sont abordés. Dans un premier temps, le but recherché est la synthèse d’une série de molécules présentant une activité anti-coccidienne pour le traitement préventif des poulets. Quarante-trois composés originaux, issus d’une synthèse courte à deux ou trois étapes, ont été préparés par hémi-synthèse de la monensine. Quinze molécules ont été testées in vitro et trois d’entre elles montrent une activité importante vis-à-vis du parasite Eimeria tenella. Dans un second temps, nous nous sommes intéressés à la synthèse de nouveaux répulsifs pour un large panel d’insectes. Après avoir fait une étude bibliographique approfondie, nos recherches se sont concentrées sur la réactivité de la coumarine. Environ soixante-dix molécules ont été synthétisées par modifications fonctionnelles des 4-, 6- et 7- hydroxycoumarines et de la coumarine. La grande majorité a été testée en présence de drosophiles. Six molécules présentant une activité répulsive équivalente à celle du DEET, produit de référence, ont été identifiées / This thesis was completed in collaboration with the Animal Health Company Merial. The objective of the thesis is the synthesis of preventive and therapeutic bioactive molecules. Two separate subjects were treated. First, the aim was the synthesis of a series of molecules having an anticoccidial activity for the preventive treatment of chickens. Forty-three original compounds, issued from a short synthesis with two or three steps, were prepared from monensin by hemi-synthesis. Among them, fifteen were tested in vitro and three of them showed a significant activity against Eimeria tenella. Thereafter, we have worked on the synthesis of new repellents for a wide range of insects. After a comprehensive bibliographic study, our research was focused on the coumarin reactivity. More than seventy molecules were synthesized by structural modifications of 4-, 6- and 7-hydroxycoumarins and of coumarin. Almost all the compounds were tested in the presence of drosophila. Six molecules showing a repellent activity equivalent to DEET, used as a reference product, were identified

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