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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.
91

Resistência de Brevipalpus phoenicis (Geijskes, 1939) (Acari: Tenuipalpidae) ao acaricida hexitiazox em citros. / Resistance of Brevipalpus phoenicis (Geijskes, 1939) (Acari: Tenuipalpidae) to the acaricide hexythiazox in citrus.

Fernando Joly Campos 28 January 2002 (has links)
O objetivo desse trabalho foi o de coletar informações básicas para a implementação de um programa de manejo da resistência de Brevipalpus phoenicis (Geijskes, 1939) ao acaricida hexitiazox na cultura de citros. A suscetibilidade de ovos de B. phoenicis a hexitiazox foi avaliada através de um bioensaio de contato direto. Foi verificado que há efeito da idade de ovos de B. phoenicis na suscetibilidade, sendo que ovos no início do desenvolvimento embrionário (1 a 3 dias) foram menos tolerantes a hexitiazox do que ovos de 4 a 9 dias de idade. A CL50 estimada para a população suscetível de referência (linhagem S) foi de 0,89 mg de hexitiazox/L de água (IC 95% 0,75-1,03). Para o isolamento da resistência de B. phoenicis a hexitiazox (linhagem R), um trabalho de seleção em condições laboratoriais foi realizado a partir de uma população coletada em um pomar de citros da região de Barretos-SP, onde o uso de hexitiazox tinha sido intenso e falhas no controle do ácaro haviam sido reportadas com esse acaricida. A intensidade da resistência de B. phoenicis a hexitiazox foi maior que 10.000 vezes. Concentrações discriminatórias entre 10 e 320 mg de hexitiazox/L de água foram definidas para um programa de monitoramento da resistência de B. phoenicis ao hexitiazox. Resultados do levantamento da suscetibilidade a hexitiazox em populações de B. phoenicis provenientes de diferentes pomares dos Estados de São Paulo e Minas Gerais revelaram uma grande variabilidade na freqüência de resistência. Não foi observada relação entre o regime de uso do hexitiazox e a freqüência de resistência. Estudos da dinâmica da resistência em laboratório revelaram que a resistência de B. phoenicis a hexitiazox é estável, isto é, a freqüência de resistência não diminui significativamente na ausência de pressão de seleção. Portanto, os resultados obtidos no presente trabalho indicam a necessidade de implementação imediata de estratégias de manejo da resistência de B. phoenicis a hexitiazox para a prolongar a vida útil desse acaricida. / The objective of this study was to collect baseline information for implementing an acaricide resistance management program of Brevipalpus phoenicis (Geijskes, 1939) to hexythiazox in citrus. The egg susceptibility of B. phoenicis to hexythiazox was measured by a direct contact bioassay. It was observed a significant effect of the egg developmental stage on susceptibility; that is, 1 to 3-day old eggs were less tolerant to hexythiazox than 4 to 9-day old eggs. The estimated LC50 for the S strain was 0.89 mg of hexythiazox/L of water (95% CI 0.75-1.03). To isolate hexythiazox-resistant B. phoenicis, a laboratory selection was conducted with a field population collected in a citrus grove located in Barretos-SP, where the intensity of hexythiazox use was high and field failures in the control of B. phoenicis were reported with the use of this acaricide. The intensity of resistance was greater than 10,000- fold. Discriminating concentrations between 10 and 320 mg of hexythiazox/L of water were defined for monitoring the resistance of B. phoenicis to hexythiazox. Results from a survey of susceptibility of B. phoenicis populations collected from citrus groves located in the State of São Paulo and Minas Gerais revealed a great variability in the frequency of resistance. No correlation was observed between the intensity of hexythiazox use and the frequency of resistance. Studies on dynamics of resistance showed that the resistance of B. phoenicis to hexythiazox is stable under laboratory conditions; that is the frequency of resistance did not decline significantly in the absence of selection pressure. Therefore, results obtained herein indicate the urgent need to implement resistance management strategies of B. phoenicis to hexythiazox in order to prolong the lifetime of this acaricide.
92

Die stiefma, ou mites en nuwe verhale : 'n pastorale narratiewe dekonstruksie

Kruidenier, Carina Maretha (Retha) January 2014 (has links)
In hierdie studie word stiefma’s en die mites wat daar oor stiefma’s bestaan, ondersoek. Dit word gedoen in die postfundamentele praktiese teologie en volgens die narratiewe benadering. Die studie word ook gedoen in die sosiaal-konstruksionistiese paradigma. Vier stiefma’s se unieke verhale oor stiefma-wees word weergegee. Nadat die stories geinterpreteer is, is diskoerse vasgestel wat ‘n invloed het op die mites wat daar oor stiefma’s bestaan. Daar word onder andere gekyk na sprokies en die oorsprong daarvan. Daar word ook gekyk na families deur die eeue, asook na moederskap. Die Godstaal wat die stiefma’s gebruik het, word ook ondersoek. Daar is ‘n interdissiplinêre ondersoek gedoen aan die hand van transversale rasionaliteit. Hierdie verhale wys onder andere op die druk wat op stiefma’s geplaas word deur die kerk en gemeenskap om onmiddelik in die rol van ‘n ma te funksioneer en die perfekte gesin te hê. Konflik in die nuwe gesin gee ook aanleiding tot skuldgevoelens by die stiefma. Met hierdie studie word daar gepoog dat daar beter begrip vir stiefma’s se unieke omstandighede en rolle sal wees. Dus ontstaan nuwe verhale, wat weer moontlikhede vir nuwe navorsing skep. / Thesis (PhD)--University of Pretoria, 2014. / gm2014 / Practical Theology / Unrestricted
93

β-Glucan Exacerbates Allergic Airway Responses to House Dust Mite Allergen

Hadebe, Sabelo, Kirstein, Frank, Fierens, Kaat, Redelinghuys, Pierre, Murray, Graeme I., Williams, David L., Lambrecht, Bart N., Brombacher, Frank, Brown, Gordon D. 02 April 2016 (has links)
β-(1,3)-Glucan is present in mould cell walls and frequently detected in house dust mite (HDM) faeces. β-Glucan exposure is thought to be associated with pulmonary allergic inflammation in mouse and man, although the published data are inconsistent. Here, we show that highly purified β-glucan exacerbates HDM-induced eosinophilic, T helper 2 type airway responses by acting as an adjuvant, promoting activation, proliferation and polarisation of HDM-specific T cells (1-Derβ T cells). We therefore provide definitive evidence that β-glucan can influence allergic pulmonary inflammation.
94

A New Microinvertebrate With Features of Mites and Tardigrades in Dominican Amber

Poinar, George, Nelson, Diane R. 01 December 2019 (has links)
From time to time, small, fragile, previously unknown fossil invertebrates are found in specialized habitats. Occasionally, as in the present case, a fragment of the original habitat that existed millions of years ago is also preserved. The present article describes a previously unknown microinvertebrate in Dominican amber that cannot be placed in any group of extant invertebrates. Placed in a new family, genus, and species, the fossil shares characters with both tardigrades and mites, but clearly belongs to neither group. The several hundred fossil individuals preserved in the amber shared their moist, warm habitat with pseudoscorpions, nematodes, fungi, and protozoa. The large number of fossils provided additional evidence of their biology, including their reproductive behavior, developmental stages, and food. While there is no extant group that can accommodate these fossils, and we have no knowledge of any extant descendants, this discovery shows that unique lineages of minute invertebrates were surviving in the mid-Tertiary.
95

Indoor Environmental Quality within an Elementary School Classroom: Measurements of <em>Felis domesticus</em> I, <em>Dermatophagoides pteronyssinus</em> I, <em>Dermatophagoides farinae</em> I, and <em>Blatella germanica</em> in Carpeting

Fowler, Jennifer 03 April 2009 (has links)
The United States Environmental Protection Agency acknowledges that indoor environments can impact the health of students and can affect concentration, attendance, and student performance (USEPA 2008). In a school year, children are required by the Florida Department of Education to be in school for a total of 180 days, which is 795 hours spent in a classroom (FLDOE 2008). In the elementary school setting, kindergarten classes typically spend a portion of the school day with floor-based activities. The American Lung Association (ALA) states that over 6.8 million children under the age of 18 are affected by asthma (ALA 2008). Allergic reactions and/or sensitization to allergens such as dust, animal dander, and cockroaches are among triggers associated with asthma cases. Literature suggests looking at the areas where individuals spend a considerable amount of time to identify potential exposure sources. Currently, many of these studies have been done regarding the home indoor environment; however, few specifically document the concentrations in carpeting in elementary schools and the exposure time associated with floor-based activities. The objective of this research was to quantify the concentrations of cat (Felis domesticus I), dust mite (Dermatophagoides pteronyssinus I, Dermatophagoides farinae I), and cockroach (Blatella germanica) allergens in carpeting in an elementary school kindergarten class and to document and quantify student group activities that are floor-based. One Florida elementary school classroom was identified as the study site. A total of eight reservoir dust samples were collected during the school year to be analyzed for Felis domesticus I, Dermatophagoides pteronyssinus I, Dermatophagoides farinae I, and Blatella germanica allergens. The sampling reservoir was the carpeting used for group floor-based activities by the school children. Dust samples from the carpet were analyzed by The Johns Hopkins University Reference Laboratory for Dermatology, Allergy, and Clinical Immunology (DACI). The sample collection methodology followed the "Dust Analysis Instructions for Use" provided by the DACI laboratory, along with the "nozzle sock" sampling media. Following discussions with the kindergarten teacher regarding curriculum and scheduled classroom activities, group floor activities were identified. The kindergarten class was observed periodically throughout a school year to document and quantify classroom activities that were floor-based. The information documented includes: occupancy of classroom, occupied floor area, occupant density, and time spent on carpeting. Felis domesticus I (Fel d I) measurements ranged from 2,206 - 10,558 ng of allergen/g of settled dust, Dermatophagoides pteronyssinus I (Der p I) measurements ranged from 3,408 - 86,704 ng/g and Dermatophagoides farinae I (Der f I) measurements ranged from 704 - 6,720 ng/g, and Blatella germanica (Bla g I) measurements were below detection limits. Based upon the DACI criteria, dust mite concentrations were moderate to high and cat concentrations were low to moderate. Kindergarten children spent approximately 38% of classroom time in floor-based activities.
96

Application of Food-grade Ingredient Treated Nets to Control Tyrophagus Putrescentiae (Schrank) (Sarcoptiformes: Acaridae) Infestations on Dry Cured Hams

Zhang, Xue 08 December 2017 (has links)
Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), also known as the ham mite, may infest dry cured hams during the aging process. The fumigant methyl bromide is currently used to control mite infestations, but eventually will not be available for use since it contributes to the depletion of the ozone layer. The use of ham nets treated with xanthan gum, carrageenan, propylene glycol alginate, propylene glycol (PG), and lard were evaluated for their impact on mite orientation to or oviposition on treated or untreated ham cubes, mite reproduction and population growth over a 10-week period. When nets were infused with gum and PG, behavioral tests indicated that greater than 95% of the mites oriented to the ham cubes that were wrapped in untreated nets when compared to treated nets and no eggs were laid on the latter. The reproduction assays indicated that there were fewer (P < 0.05) T. putrescentiae produced over a two-week period on ham cubes covered with both gum and PG treated nets when compared to the untreated or gum-only treated nets over the 10-week storage period of the experiment. Medium and high concentrations of PG treatments had the lowest mite reproduction rates. No more than four mites could be found on each of these treatments in comparison to 200-300 mites that were on the untreated ham cubes. When nets were infused with gum, PG, and lard, behavioral tests indicated that fewer mites oriented to the ham cubes that were wrapped with gum, lard, and medium PG than those with untreated nets. The oviposition assays revealed that on average less than three eggs were laid on the ham cubes with treated nets in comparison to 69-165 eggs on the untreated ham cubes. Reproduction assays demonstrated that fewer T. putrescentiae (P < 0.05) were on ham cubes with treated nets containing PG when compared to the number of mites on ham cubes with untreated nets over 10 weeks of storage. Lard infused nets without PG did not decrease the mite population (P > 0.05). The net without coating slowed the growth and reproduction of T. putrescentiae since net controls had fewer mites (P < 0.05) than controls without nets. With a few exceptions, fungi were not present on ham cubes that were treated with PG-containing nets over 10 weeks of storage. This research demonstrated the efficacy of using nets treated with food-grade ingredients during ham aging to control mite infestations on a laboratory scale. Further research will be conducted to determine the effectiveness of the same treated nets on whole hams in commercial aging rooms.
97

BMPR2 and mTOR Signaling Pathways in Inflammatory Lung Diseases

Mushaben, Elizabeth M. January 2012 (has links)
No description available.
98

Role of the EGFR Pathway in Lung Remodeling and Disease

Kramer, Elizabeth L. January 2009 (has links)
No description available.
99

Phenotyping of chronic respiratory diseases in the South of Vietnam

Chu Thi, Ha 25 June 2019 (has links) (PDF)
Chronic respiratory diseases (CRDs) include chronic diseases involving the airways and other structures of the lung. In the current circumstance of Vietnam, people are exposed to numerous risk factors of CRD, such as heavy smoking, high frequency of pulmonary tuberculosis, chronic helminthiasis, allergic factors, migration and urbanization (the last associated with traffic-related pollution). The phenotype diagnoses should take into account the risk factors of each individual besides the clinical features, while the differential diagnoses mostly depend on the available techniques in each healthcare center. Our aim was to improve the differential diagnoses of the 3 most frequent CRDs: chronic obstructive pulmonary disease (COPD), asthma and COPD – asthma overlap syndrome (ACOS), in Vietnam. In the first part, we evaluated the prevalence of the allergen sensitization among patients with CRD, in regard to the urban and rural area in the South of Vietnam. House dust mites and cockroach droppings were the most frequent sensitizer. Compared with participants born in the urban setting, those born in the rural environment were less frequently sensitized and this protective effect disappeared in the case of migration from rural to urban areas. In the second part, we evaluated skin prick test as a method to screen dust mite sensitization in CRD in southern Vietnam. The data suggested that, in the present circumstance, skin prick test can be used to screen mite sensitization. In the third part, we evaluated the risk of mite sensitization in the native and migrant population, in regard to several environmental factors. Consistently with the hygiene hypothesis, compared to urban, exposure to high endotoxin concentration in rural was a protective factor against allergic sensitization. We reported for the first time that this effect was reversible among the migrants from rural to urban setting in association with lower endotoxin exposure. In the fourth part, we have defined asthma, COPD and ACOS based on clinical symptoms, cumulative smoking and airway expiratory flow with reversibility, on one side, and the age-related of the different phenotypes, on the other side. We hypothesized that the cumulative exposure to noxious particles should increase the age-related prevalence of COPD, while due to the immunosenescence process, the prevalence of IgE-mediated asthma should decrease with age, and ACOS prevalence being not related to age due to the combined mechanisms.  In conclusion, we showed in the South of Vietnam that:1) mites and cockroach allergens were the most frequent sensitizer in chronic respiratory diseases;2) the skin prick test to mite has been validated to screen mite sensitization;3) associated with a reduced level of endotoxin level, migration from rural to the urban setting was a risk factor of mite sensitization in chronic respiratory diseases;4) based on the clinical symptoms, spirometric values, and cumulative smoking, the diagnosis of asthma, COPD and ACOS have been made and their prevalence were 25, 42 and 33%, respectively. / Doctorat en Sciences biomédicales et pharmaceutiques (Médecine) / info:eu-repo/semantics/nonPublished
100

Ação de biofertilizantes líquidos sobre a bioecologia do ácaro Brevipalpus phoenicis. / Biofertilizer action in the Brevipalpus phoenicis bioecology.

Medeiros, Marcos Barros de 25 September 2002 (has links)
Esta pesquisa foi conduzida para avaliar os efeitos de interações entre a planta hospedeira e um biofertilizante líquido sobre o ácaro Brevipalpus phoenicis (Geijskes). Primeiramente avaliaram-se os efeitos residual e sistêmico de biofertilizantes aplicados a plantas de Canaialia etlçifbrmis (L.) DC. sobre parâmetros bioecológicos de uma população de B. phoenicis. Para o efeito residual foram testados os seguintes tratamentos: a) Água destilada (Controle); b) Biofert -- biofertilizante produzido em um único bioreactor; e) Biornix - uma mistura com biol@ertilizantes produzidos em quatro bioreatores; e d) Bio+VL - Biofert + Verticillium leca;,iii (Zimm.) Viégas. Para o efeito sistêmico somente dois tratamentos foram avaliados: a) Biofert e b) Água destilada (Controle). A seguida avaliou-se a interação tópica e residual entre concentrações do biofertilízante nas plantas hospedeiras: C. ensíformis e Ligustnim lucindum Aiton. Utilizando-se n-úcroscopia eletrônica de varredura (MEV), caracterizaram-se as manifestações patológicas sobre os cadáveres de 8. phoenicis. Foram observados efeitos adversos do biofertilizante sobre os parânietros de sobrevivência e de oviposição. A taxa líquida de reprodução (Ro)foi de 18,1; 12,9; 12,5 e 10,5 fêmea/fêmea (efeito residual) e 19,4 e 13,0 fêmea/fêrnea (efeito sistêmico), respectivamente para os tratamentos nas ordens supra mencionadas. Tanto na ação residual quanto via sistêmica houve redução significativa do potencial de crescimento populacional de B. phoenicis. Nas duas plantas hospedeiras a sobrevivência e oviposição do ácaro foram significativamente reduzidas com o aw-nento de concentração do biofertilizante, sendo mais severo em C ensijbrmis. Evidenciou-se uma colonização microbiana nos ácaros mortos pela ação do biofertilizante e também verificou-se que um composto coloidal do biofertilizante causou imobilização e obstrução do sistema digestivo do ácaro. A interação entre a planta hospedeira e o biofertilizante, numa relação de equilíbrio trofobiótico, contribui para um melhor manejo desse ácaro. / This study was conducted to evaluate interactions between host plants and the effect of biofertilizers on Brevipalpits phoeiiicis (Geijskes) bioecology. The residual and systemic effects of biofertilizer mjxtures sprayed on Canavalia ensiformis (L.) DC. plants on the bioecology parameters were firstly evaluated. For the residual effect bioassay the following treaúnents were tested: a) Distilled water (Control); b) Biofert biofertilizer produced in a single bioreactor; e) Biomix - a mix of biofertilizers produced in four bioreactors; and d) Bio+VL - Biofei-t, + Verticilliuin lecanii (Zimm.) Viégas. For tbe systemic effect bloassay two stispensions were tested: a) Biofert and b) Distilled water (Control). Thereafter the topical and residual interaction effects between concentrations of the biofertilizer and C. ensiformis and Ligustrum lucidum Aiton. Host plants were evaluated. Were also characterized pathological manifestations in the dead mites by using seanning electronic microscopy images. Adverse effects of biofertilizers on both survival and oviposition parameters were verified. The net reproduction rates (Ro) were 18.09; 12.92; 12.52 and 10.52 female/female (residual effect) and 19.42 and 13.00 female/female (systemic effect), respectively, for the treatments in the above mentioned orders. The results showed that the biofertilizers reduced the potential population growth of B. phoenicis in the residual and in the systemie effect assays. The biofertilizer demonstrated deleterious effect on fertility and survival of R. phoenicis on both host plants, mostly on C ens@formis. The mites dead by biofertilizer action showed evidences of microbial colonization. A colloidal coinpound of biofertilizer induced mite immobilization and obstruction in its digestivo tract. The interaction between host plant and biofertilizer deleterious effects will contribute to enhance mite management based on trophobiotic relationships.

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