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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.
41

Toxoptera citricidus (Kirkaldy,1907) (HEMIPTERA : APHIDIDAE) : aspectos biológicos e respostas às ações de bioinseticidas / Toxoptera citricidus (Kirkaldy, 1907) (Hemiptera : Aphididae) : biological aspects and answers to bioinsecticides actions

Gambarra, Wanessa Porto Tito 11 September 2015 (has links)
Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-09-26T19:12:51Z No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:33:46Z (GMT) No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-04T18:33:51Z (GMT) No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) / Made available in DSpace on 2016-10-04T18:34:00Z (GMT). No. of bitstreams: 1 TeseWPTG.pdf: 8829688 bytes, checksum: b3e17827424a33d80b946014119c4790 (MD5) Previous issue date: 2015-09-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Aphids are important pests in agriculture, mainly because they are vectors of phyto-pathogenic virus. One of the ways to control these insects, is the use of botanical insecticides. However in order to the control to be effective it is also necessary to know their biological characteristics. In this context, the aim of the present study was to evaluate the bioactivity of several plant extracts upon Toxoptera citricidus, presently considered one of the most important pests of citric plantations. For this purpose its life cycle has been studies and important metabolic processes as: consumption, production, respiration and excretion were quantified. Based on these data the species life table and energy budget were constructed. The bioactivity of 11 species of plants including a nanoformulation of the neen, Azadirachta indica, was evaluated through acute toxicity tests. T. citricidus was maintained on Citrus limonia under controlled constant conditions in the laboratory. Among these 5 had insecticide activity upon T. citricidus causing mortality to 80 % of the individuals tested or more. The lethal median concentration (CL50 48h) varied from 0.17 to 4.10 mg/mL for the nynphal phases and from 0.30 to 5.01 mg/mL to adults thus evidencing insecticide properties and presenting high to be used in the management of this pest. A magnetic nuclear ressonance of honeydew, the excretion product of this aphid, evidenced the presence of important aminoacids besides carbohydrates allowing an advance in the knowledge on aphid-ants and aphid- host plant. The total energy budget of of T. citricidus varied According to the aphid age. Mean daily energy consumption were 0.3717 cal for nymphs and 0.4761cal for adults. The energy fraction invested in production by T. citricidus was high, with a mean value around 60%, evidencing high efficiency of energy retention. It was concluded that considering its biological characteristics T. citricidus has a relevant role in the energy transference across the ecosystem. / Os afídeos são importantes pragas na agricultura, principalmente por serem vetores de vírus fitopatogênicos. Entre as formas de controle desses insetos, estão incluídos os inseticidas botânicos, no entanto, para que o seu controle seja eficiente é necessário também que se conheçam as suas características biológicas. Nesse contexto, esse trabalho teve como objetivo avaliar a bioatividade de diversos extratos vegetais sobre Toxoptera citricidus, considerado uma das mais importantes pragas das plantações cítricas. Para isso foi estudado o ciclo de vida e quantificados importantes processos metabólicos, como: consumo, produção, respiração e excreção, e com base nestes, determinado o balanço energético e construída a tabela de vida da espécie. A bioatividade de 11 espécies de plantas incluindo uma nanoformulação do nim, Azadirachta indica, foi avaliada por meio de toxicidade aguda. Para isso T. citricidus foi mantida sobre Citrus limonia em condições controladas e contantes de laboratório. Destas, 5 espécies tiveram ação inseticida sobre T. citricidus, causando mortalidade igual ou superior a 80%. A concentração letal mediana (CL50) variou de 0,17 a 4,10 mg/mL para ninfas e de 0,30 a 5,01 mg/mL para adultos, assim evidenciando propriedades inseticidas e apresentando elevado potencial para serem utilizados no manejo dessa praga. Uma análise por ressonância magnética nuclear do honeydew permitiu evidenciar a presença de importantes aminoácidos além de carboidratos permitindo aprofundar o conhecimento sobre as interações afídeo-formiga e afídeoplanta hospedeira. O balanço energético total do T. citricidus variou dependendo da idade do afídeo. O consumo energético diário foi em média 0,3717 cal para as ninfas e de 0,4761 cal para os adultos. A fração energética à produção foi bastante elevada, em média 60%, evidenciando alta eficiência na retenção de energia. Conclui-se que T. citricidus tem importante papel na transferência de energia através dos ecossistemas.
42

Desenvolvimento e reprodução do predador Podisus nigrispinus (Het.: Pentatomidae) em plantas de soja com os fungicidas epoxiconazole + piraclostrobina, tetraconazole ou tebuconazole / Development and reproduction of the predator Podisus nigrispinus (Het.: Pentatomidae) in soybean plants with the fungicides epoxiconazole + piraclostrobina, tetraconazole or tebuconazole

Lacerda, Mabio Chrisley 15 February 2006 (has links)
Made available in DSpace on 2015-03-26T13:40:08Z (GMT). No. of bitstreams: 1 texto completo.pdf: 492515 bytes, checksum: 668ea65946c1df0b0c6b0aa8a1574dc3 (MD5) Previous issue date: 2006-02-15 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The predator Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) is an important agent of biological control found in different cultures including soybean. The use of pesticides can reduce the diversity of the fauna and to increase the susceptibility of this culture to pests. The objective of this research was to verify the effect of fungicides, commonly used in the soybean culture, in the reproductive parameters of P. nigrispinus. The treatments consisted of the control with the application of only water and spreader-sticker (treatment T1); plants treated with the fungicide epoxiconazole + piraclostrobina (Opera®) (treatment T2); tetraconazole (Domark®) (treatment T3); tebuconazole (Folicur®) (treatment T4); and rotation of these products (Opera®/Domark®/ Folicur®/ Opera®) (treatment T5). Soybean plants were immersed during five seconds in the fungicide solution with the dosage recommended by the manufacturers. Second instar nymphs of P. nigrispinus were taken to the field and conditioned in organza bags involving a trifoliate soybean leaf, two hours after the treatment with the fungicide solution. Seventy five percent or more of the eggs of P. nigrispinus were laid up to the 37th day after the emergency of its females. The numbers of eggs and of nymphs per female and of nymphs per egg mass were higher in the treatment with the tebuconazole than that with the tetraconazole. The oviposition peak of P. nigrispinus was recorded between the 20th and the 30th days (60% of the eggs laid) of the adult stage in all treatments. The finite (λ) and the infinitesimal (rm) reason of population increase showed higher values in the control, but P. nigrispinus had population growth in all treatments. The period of the population of this predator to double its population in number of individuals (TD) was longer in the treatments with the fungicides epoxiconazole + piraclostrobina, tebuconazole and the rotation of these products than in the control and in the treatment with the tetraconazole. The liquid reproductive rate (Ro) was lower in the control and in the treatment with the tetraconazole than in that with the tebuconazole. The fungicides tested are compatible with P. nigrispinus what indicates that these products can be used in programs of biological control in the soybean culture with this predator. However, the tebuconazole presented better results and it can stimulate the population increase of P. nigrispinus. / O percevejo predador Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) destaca-se entre os agentes de controle biológico encontrados na cultura da soja. O uso de agrotóxicos pode reduzir a diversidade faunística e aumentar a suscetibilidade dessa cultura ao ataque de pragas. Assim, o objetivo desse trabalho foi verificar o efeito de fungicidas, comumente utilizados na cultura da soja, nos parâmetros reprodutivos de P. nigrispinus. Os tratamentos constaram da testemunha com apenas água e espalhante adesivo (tratamento T1); plantas tratadas com o fungicida epoxiconazole + piraclostrobina (Opera®) (tratamento T2); tetraconazole (Domark®) (tratamento T3); tebuconazole (Folicur®) (tratamento T4); e rotação desses produtos (Opera®/Domark®/Folicur®/Opera®) (tratamento T5). Plantas de soja foram imersas por cinco segundos na calda fungicida na dosagem recomendada pelo fabricante. Ninfas de segundo estádio de P. nigrispinus foram levadas a campo e acondicionadas em sacos de tecido organza envolvendo uma folha trifoliolada de soja, duas horas após o tratamento com a calda fungicida. Setenta e cinco por cento ou mais dos ovos de P. nigrispinus foram colocados até o 37º dia da emergência de suas fêmeas. O número de ovos e de ninfas por fêmea e de ninfas por postura foram maiores no tratamento com tebuconazole em relação ao com tetraconazole. O pico de oviposição de P. nigrispinus ocorreu entre os 20º e 30º dias (60% dos ovos colocados) em todos os tratamentos. A razão finita (λ) e a infinitesimal (rm) de aumento populacional tiveram maiores valores na testemunha, porém P. nigrispinus mostrou crescimento populacional em todos os tratamentos. O período para a população desse predador dobrar em número de indivíduos (TD) foi maior nos tratamentos com os fungicidas epoxiconazole + piraclostrobina, tebuconazole e a rotação de produtos que na testemunha e no tratamento com tetraconazole. A taxa líquida de reprodução (Ro) foi menor na testemunha e no tratamento com o tetraconazole que naquele com o tebuconazole. Os fungicidas foram compatíveis com P. nigrispinus, o que indica que esses produtos podem ser utilizados em programas de controle biológico na cultura da soja com esse predador. No entanto, o tebuconazole apresentou melhores resultados e pode estimular o aumento populacional de P. nigrispinus.
43

Estudos bioecológicos de Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) para o controle de Diaphorina citri Kuwayama, 1907 (Hemiptera: Psyllidae) / Bioecological studies on Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in the control of Diaphorina citri Kuwayama, 1907 (Hemiptera: Psyllidae)

Gómez Torres, Mariuxi Lorena 08 April 2009 (has links)
Desde 2004 foram detectadas, nas áreas citrícolas paulistas, as bactérias responsáveis pela principal doença de citros no mundo, o huanglongbing ou greening. A ampla distribuição no Brasil do psilídeo vetor, Diaphorina citri e a presença do patógeno nas áreas citrícolas é um fator limitante à produção. Tamarixia radiata é o principal agente de controle biológico de D. citri. Assim, os objetivos do presente estudo foram: a) realizar o levantamento populacional de T. radiata nas regiões citrícolas do estado São Paulo; b) caracterizar o policromismo em populações do parasitóide provenientes das principais regiões citrícolas do estado; c) estudar a biologia de T. radiata em condições de laboratório; d) avaliar a capacidade de parasitismo em diferentes temperaturas; e) determinar, mediante liberações em pomares cítricos comerciais, a eficiência de T. radiata para o controle de D. citri; f) determinar a ocorrência e efeitos no parasitismo da associação T. radiata - Wolbachia; g) realizar o zoneamento agroecológico de D. citri e T. radiata com base nas exigências térmicas e higrométricas para o estado de São Paulo. As populações de T. radiata coletadas em Itirapina, Pederneiras, Piracicaba e São Carlos apresentaram variações cromáticas em relação à espécie típica, sendo que as regiões ITS1 e ITS2 do rDNA das populações analisadas apresentaram de 98 a 99% de identidade. Assim, estas variações cromáticas estão relacionadas à plasticidade fenotípica intra-específica, própria de populações que se encontram em processo de adaptação ecológica. Em 24 horas, o maior parasitismo foi obtido nas temperaturas de 25 e 30°C. Este parasitóide desenvolveu-se na faixa térmica de 15 a 35°C, sendo que 25°C foi a temperatura mais adequada por proporcionar maior viabilidade do período ovo-adulto e os maiores valores da taxa liquida de reprodução (Ro) e da razão finita de aumento (). No município de Araras, oito dias após a liberação, a porcentagem de parasitismo de T. radiata se manteve entre 51,57 e 72,75%. Nos municípios de Cordeirópolis e Limeira, após três liberações, a porcentagem de parasitismo variou entre 30 e 60%. As populações coletadas em Cafelândia, Ribeirão Bonito e Piracicaba apresentaram infecção múltipla por Wolbachia. O limite térmico inferior de desenvolvimento (Tb) foi de 7,13°C e a constante térmica de 188,7GD. Mediante um Sistema de Informação Geográfica, foram obtidos mapas de distribuição do desenvolvimento de T. radiata e D. citri. Assim, ao longo do ano podem ocorrer, na região norte, de 10 a 13 ciclos de D. citri e de 31 a 35 ciclos de T. radiata; na região nordeste, o número de ciclos pode variar de 6 a 10 e de 24 a 31 para a praga e para o parasitóide, respectivamente; nas regiões sudoeste e sudeste, o número de gerações pode variar de 3 a 10 e de 19 a 31 para D. citri e T. radiata. Verificando estes aspectos da interação T. radiata e D. citri, os dados obtidos no presente trabalho poderão auxiliar para a implementação de um programa de controle biológico, como parte do manejo de D. citri, em regiões ecologicamente distintas do estado de São Paulo. / Since 2004, have been detected in citrus-growing areas of São Paulo, the bacterias that are responsible for the main disease of citrus worldwide, known as greening or huanglongbing. The widespread distribution in Brazil of the vector psyllid, Diaphorina citri and the presence of the pathogen in citrus-growing areas is a limiting factor for production. Tamarixia radiata is the most important biological control agent against D. citri. Therefore, the objectives of this study were to: a) conduct a population survey of T. radiata in the citrus-growing regions of the State of São Paulo; b) characterize polychromism in populations of the parasitoid from the main growing regions in the State of São Paulo; c) study the biology of T. radiata under laboratory conditions; d) evaluate the parasitism capacity at different temperatures; e) determine, by means of releases in commercial citrus orchards, the effectiveness of T. radiata for the control of D. citri; f) determine the occurrence and effects on parasitism of the T. radiata - Wolbachia association; g) prepare an agroecological zoning of D. citri and T. radiata for the State of São Paulo based on their temperature and humidity requirements. T. radiata populations collected in Itirapina, Pederneiras, Piracicaba, and São Carlos showed chromatic variations in relation to the typical species; the ITS1 and ITS2 rDNA regions of the populations analyzed had between 98 and 99% identity. Consequently, these chromatic variations are related to the intraspecific phenotypic plasticity characteristic of populations that are undergoing a process of ecological adaptation. In a 24-hour period, the highest parasitism of T. radiata was obtained at 25 and 30°C. This parasitoid developed in the temperature range from 15 to 35°C; the most suitable temperature was 25°C, since it gave the highest viability for the egg-adult period, and the highest net reproductive rate (Ro) and finite rate of increase values (). In the municipality of Araras, T. radiata parasitism percentage values eight days after release remained between 51.57 and 72.75%. In the areas selected in the municipalities of Cordeirópolis and Limeira, the parasitism percentage of T. radiata after three releases ranged between 30 and 60%. The populations collected in Cafelândia, Ribeirão Bonito, and Piracicaba showed multiple infections by Wolbachia. The parasitoids lower temperature development threshold (Tb) was 7.13°C, with a thermal constant of 188.7 GDD. Distribution maps for T. radiata and D. citri development in the State of São Paulo were obtained by means of a Geographic Information System (GIS). According to those, from 10 to 13 D. citri cycles and from 31 to 35 T. radiata cycles may occur in the northern region over the course of one year; in the northeastern region, the numbers of cycles may vary from 6 to 10 and from 24 to 31 for the pest and the parasitoid, respectively; in the southwest and southeast regions the numbers of generations may vary from 3 to 10 and from 19 to 31 for D. citri and T. radiata. Based on these aspects of the T. radiata × D. citri interaction, the data obtained in this work can be useful for the implement a biological control program as part of D. citri management in ecologically distinct regions of the State of São Paulo.
44

居住地的死亡風險:一九九七年台灣地區鄉鎮市區平均餘命的統計地圖

林孫弘, Curtis Lin Unknown Date (has links)
從1906到1999年間,台灣地區男性出生時平均餘命增加了43.55歲,女性增加了47.63歲,雖然台灣地區平均餘命不斷地在增加,地區間死亡風險的差異情形則未有所改善。本研究以生命表方式計算台灣地區縣市級、鄉鎮級平均餘命,尤以鄉鎮級為研究重心,配合統計地圖的使用以瞭解小地區間死亡風險的差異情形。 在縣市層級方面,男性與女性出生時平均餘命皆以七大都市較高,西部其他地區次之,東部地區的花蓮縣、台東縣最低。各縣市出生時平均餘命的差異,正指出各縣市之間的死亡風險差異甚大,特別是東部地區明顯地比西部地區更處於不利的狀態。 在鄉鎮層級方面,男性與女性各生命階段平均餘命皆呈現出西部地區高、東部地區低的明顯差異,而且平均餘命數值越低的地區其兩性平均餘命的差距也越大,此種現象尤以男性平均餘命越低的地區越為明顯。在空間模式上,男、女平均餘命最高的地區皆以大都市為中心向外擴散至其鄰近地區,平均餘命最低的地區則廣散在山地鄉之間。總的來說,中央山脈兩側的鄉鎮不僅死亡風險較其他地區高、兩性的死亡風險差異大,山地鄉之間的死亡風險結構更是呈現高度的異質性。 關鍵字:鄉鎮市區、死亡風險、平均餘命、性別差異、統計地圖、空間模式。 / Over the twentieth century (1906-1999), the life expectancy at birth in Taiwan has increased 43.55 and 47.63 years for males and females respectively. Undoubtedly, such a dramatic increase in life expectancy is resulted from the improvement of living quality in Taiwan over the past century. Nevertheless, after detailed examination of historical data, it shows that the areal variation in life expectancy over the life cycle is significant and has never diminished. This study, by applying the life table methods and statistical maps, attempts to analyze the areal variation in risks of death at small areas in Taiwan. The data sources for achieving this purpose come from the vital statistics and death-registration- profiles. The research findings show that life expectancies for both males and females are highest in the most-developed urban counties. On the contrary, the life expectancies are lower in rural counties. The gaps in life expectancies at birth between Taipei City and Taitung county reach 11 years and 7 years for males and females respectively. The spatial pattern of variation in life expectancy at the township-level is consistent with the research findings at the county-level. In general, the life expectancies for townships within the central metropolitan area are highest, and then gradually decrease for townships distant from the metropolis center. The life expectancies for both males and females are lowest in the rural-mountain townships. The gap in life expectancies between males and females is also larger in these rural-mountain areas. Finally, the life expectancies for the aboriginal townships are lowest in Taiwan. However, the age profiles for risks of death are heterogeneous in these aboriginal townships. Keywords: life expectancy, life table, statistical maps, spatial pattern
45

慢性B型肝炎病毒感染之年齡相關模型及存活機率分析 / An age-dependent model with survival analysis on chronic hepatitis b virus infection

陳炘毓, Chen, Shin Yu Unknown Date (has links)
在此篇論文中,我們提出一個慢性B型肝炎病毒感染病程之數學模型。因為在病症間的轉移機率(Transition probability)是隨著患者的年齡變動,所以在過去的文獻中,已經有學者提出,在疾病轉移機率模型中,應加入國民生命表(Life table),藉此讓機率模型更符合B型肝炎病患的生命歷程。但是過去的文獻中,學者並沒有利用加入國民生命表之後疾病模型做進一步的病程分析。在這篇論文當中,我們假設原始的疾病轉移模型是符合馬可夫鏈的性質,並且提出一種加入國民生命表的方法,賦予疾病有年齡相關特性之模型。根據文獻數據和類馬可夫機率性質,我們使用著名的Chapman-Kolmogorov公式計算B型肝炎的自然病程機率,並畫出病人的生存機率曲線(Survival curve)。文章最後將會藉由兩個例子來介紹此篇論文提出的模型。實驗數據結果證實,此模型不僅提供了一個更精確的方法去分析在病症與死亡間的轉移機率、平均餘命(Life expectancy)、以及在不同年齡的存活機率(Survival probability),並且可以更進一步的分析且瞭解病情狀態之間的轉移狀況。 / In this thesis, we propose a new mathematical model extending the natural history of hepatitis B virus (HBV) prognosis progression on chronic HBV infection. Since the actual transition probabilities between symptoms are dependent of ages, it has been proposed that the life table should be accommodated to the HBV prognosis progression model so that it can more properly explain the disease progression of the HBV patients. But in the literature, no further disease analysis and applications of it with the life table are discussed. In this thesis, we assume that the original disease progression is described by a Markov model, and propose a new method to combine the HBV progression with the life table so that the proposed model integrates data from the life table and allows the accommodation of age-dependent properties of the target disease. With clinical data based on annual incidence rates, the entire model is Semi-Markov based in nature. Computation methods similar to the celebrated Chapman-Kolmogorov equation can be applied to study the associated probability of each likely trajectory with desired initial ages and health states under the scenarios of natural history and various treatment policies. This method provides a more accurate way to analyze the transitions between symptoms, such as the mean life expectancy or the survival probabilities at different ages. We will give examples to demonstrate the proposed method in this thesis. Numerical results show the proposed model not only provides a more accurate method to analyze the mean life expectancy, the survival probabilities at different ages, and the transition probabilities from symptoms to death but also helps us to understand the transitions between symptoms.
46

小區域死亡率模型與生命表編算 / A Study of Mortality Models and Life Table Construction of Small Areas

鍾陳泰, Chung, Chen Tai Unknown Date (has links)
臺灣各縣市人口結構差異明顯,各縣市的人口出生、老化程度都不盡相同,而且在醫療分配及社會資源的使用也有很大的差異,因此各縣市應因應各地特性發展不同的小區域人口推估方法。由於樣本數與變異數成反比,人數較少者的死亡率(像是高齡人口)通常震盪較大,藉由適當的修勻(Graduation)調整,通常可降低年齡層間的死亡率震盪。然而,當縣市層級的人數太少時,只依賴修勻往往不足,多半會再參考人口較多的大母體之死亡率。例如:傳統的的貝氏修勻,使用Lee-Carter之類的參數死亡模型(Lee and Carter, 1992),或是透過小區域及大母體的死亡率比值(王信忠, 2012)。然而過去研究較少全面性的比較這些方法,尤其是用於人數較少(如:十萬人)的地區。 本文以探討小區域生命表及死亡率推估為目標,著眼於人數不多於五萬人,尋求較為適合臺灣及類似國家的死亡率編算方法。由於修勻或貝氏等方法可視為增加樣本數,本文將擴大樣本分為四種方式:「同地同時」、「同地異時」、「異地同時」、「異地異時」,亦即將死亡資料的整併分成是否限定於小區域,以及是否可擴及其他年度。本文藉由電腦模擬測試,提供在各種限制之下,最合適小區域生命表建構的準則。其中,本文假設大、小區域的死亡率間存有三種情境的關係:定值、遞增、V字型,藉由調整大小區域死亡率比值間的幅度,探討大母體及小區域間的差異對實務使用的影響。研究發現,Partial SMR方法是一個值得參考的方法,當大小區域死亡率類型接近時的效果不錯,甚至可用於人數小於一萬人,但若死亡率類型差異過大,修勻方法會有限制,使用時需格外謹慎。 / The population structure, life expectancy (and age-specific mortality rates), and the speed of population aging vary a lot in different county of Taiwan. Each county has its own policy planning according to the needs. However, the county level population is usually not enough to provide stable estimates, such as of the life expectancies and mortality rates at the county level. Thus, certain graduation methods are applied to stabilize these estimates. However, only a few studies focus on comparing different types of graduation methods, including traditional graduation methods, Bayesian methods, and parametric mortality models. In this study, we separate the graduation methods into four types, according to if using only the small area data and if one year or multiple years of data are used, and explore which methods are appropriate to the areas with population fewer than 100,000. We use computer simulation to evaluate the graduation methods. We found that the Standard Mortality Ratio is promising when the mortality profiles of small and large populations are similar, and it is a feasible solution even for the areas with population fewer than 10,000. However, if the mortality profiles differ significantly, all graduation methods need to be applied with care.
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Controle natural de Triozoida limbata em goiabeira / Natural control of Triozoida limbata in guava plants

Semeão, Altair Arlindo 21 December 2006 (has links)
Made available in DSpace on 2015-03-26T13:30:45Z (GMT). No. of bitstreams: 1 texto completo.pdf: 223081 bytes, checksum: ea7b424d6d7a895c4d5b4b0948ed6537 (MD5) Previous issue date: 2006-12-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / It was evaluated in this work, the natural control of Triozoida limbata (Enderlein) (Hemiptera: Sternorrhyncha: Triozidae) at three different times of the year: in the periods from 06/02/2006 to 07/25/2006, 07/29/2006 to 09/15/2006 and from 10/11/2006 to 11/24/2006. The research was carried out in an orchard of guava in the Campus of the Federal University of Viçosa, in Viçosa, MG. Ecological life table for each time had been constructed. From these life tables, the critical stages and the key factors of mortality of T. limbata had been determined. The critical stage, which determine the size of the population of T. limbata in all the evaluated times was the nymph stage. The critical instars of mortality, in the period from 06/02/2006 to 07/25/2006, were the 2º and 5º instars; and the key factors were predation in the 2nd instar and the parasitoid Psyllaephagus sp. and predation by Syrphidae larvae in the 5th instar. In the period from 07/29/2006 to 09/15/2006 the critical instars of mortalities were the 1st and the 4th. In the 1st instar, the key factor of mortality was predation. In the 4th instar, it was the predation by Vespidae the only which presented a significant correlation with the total mortality being this the mortality key factor. Finally, in the period from 10/11/2006 to 11/24/2006 the critical instar of mortality was the 4th, in this instar the predation by Vespidae was the key factor. Being the nymph stage, the one that determines the population size in all periods evaluated, then the control of T. limbata must be done during this stage and must be in a way that preserve and increase the natural control agents, which were the key factors. / Avaliou-se neste trabalho, o controle natural de Triozoida limbata (Enderlein) (Hemiptera: Sternorrhyncha: Triozidae) em três épocas do ano: nos períodos de 02/06/2006 a 25/07/2006, 29/07/2006 a 15/09/2006 e de 11/10/2006 a 24/11/2006. A pesquisa foi realizada em pomar de goiaba no Campus da Universidade Federal de Viçosa, em Viçosa, MG. Foram confeccionadas tabelas de vida ecológica para cada época. A partir dessas tabelas de vida determinaram-se as fases críticas e os fatores chave de mortalidade de T. limbata. A fase determinante do tamanho da população do T. limbata em todas as épocas avaliadas foi a fase ninfal. Os ínstares críticos de mortalidade no período de 02/06/2006 a 25/07/2006, foram o 2º e o 5º ínstares; e os fatores-chave de mortalidade foram a predação no 2º ínstar e parasitismo por Psyllaephagus sp. (Hymenoptera: Encyrtidae) e predação por larvas de Diptera: Syrphidae no 5º ínstar. No período de 02/06/2006 a 25/07/2006, os ínstares críticos de mortalidade foram o 1º e o 4º. No 1º ínstar o fator chave de mortalidade foi a predação. Já no 4º ínstar a predação por Vespidae foi a única que apresentou correlação significativa com a mortalidade total sendo este o fator chave de mortalidade. Já no período de 11/10/2006 a 24/11/2006, o ínstar crítico de mortalidade foi o 4º. Neste ínstar, a predação por Vespidae foi o fator chave de mortalidade neste período. Sendo o estádio ninfal, o período crítico determinante do tamanho da população, em todas as épocas avaliadas, então o controle da população de T. limbata deve ser realizado durante esse período, e deve ser de forma que preserve e aumente os agentes de controle natural, os quais foram os fatores-chaves de mortalidade no período crítico.
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Estudos bioecológicos de Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) para o controle de Diaphorina citri Kuwayama, 1907 (Hemiptera: Psyllidae) / Bioecological studies on Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in the control of Diaphorina citri Kuwayama, 1907 (Hemiptera: Psyllidae)

Mariuxi Lorena Gómez Torres 08 April 2009 (has links)
Desde 2004 foram detectadas, nas áreas citrícolas paulistas, as bactérias responsáveis pela principal doença de citros no mundo, o huanglongbing ou greening. A ampla distribuição no Brasil do psilídeo vetor, Diaphorina citri e a presença do patógeno nas áreas citrícolas é um fator limitante à produção. Tamarixia radiata é o principal agente de controle biológico de D. citri. Assim, os objetivos do presente estudo foram: a) realizar o levantamento populacional de T. radiata nas regiões citrícolas do estado São Paulo; b) caracterizar o policromismo em populações do parasitóide provenientes das principais regiões citrícolas do estado; c) estudar a biologia de T. radiata em condições de laboratório; d) avaliar a capacidade de parasitismo em diferentes temperaturas; e) determinar, mediante liberações em pomares cítricos comerciais, a eficiência de T. radiata para o controle de D. citri; f) determinar a ocorrência e efeitos no parasitismo da associação T. radiata - Wolbachia; g) realizar o zoneamento agroecológico de D. citri e T. radiata com base nas exigências térmicas e higrométricas para o estado de São Paulo. As populações de T. radiata coletadas em Itirapina, Pederneiras, Piracicaba e São Carlos apresentaram variações cromáticas em relação à espécie típica, sendo que as regiões ITS1 e ITS2 do rDNA das populações analisadas apresentaram de 98 a 99% de identidade. Assim, estas variações cromáticas estão relacionadas à plasticidade fenotípica intra-específica, própria de populações que se encontram em processo de adaptação ecológica. Em 24 horas, o maior parasitismo foi obtido nas temperaturas de 25 e 30°C. Este parasitóide desenvolveu-se na faixa térmica de 15 a 35°C, sendo que 25°C foi a temperatura mais adequada por proporcionar maior viabilidade do período ovo-adulto e os maiores valores da taxa liquida de reprodução (Ro) e da razão finita de aumento (). No município de Araras, oito dias após a liberação, a porcentagem de parasitismo de T. radiata se manteve entre 51,57 e 72,75%. Nos municípios de Cordeirópolis e Limeira, após três liberações, a porcentagem de parasitismo variou entre 30 e 60%. As populações coletadas em Cafelândia, Ribeirão Bonito e Piracicaba apresentaram infecção múltipla por Wolbachia. O limite térmico inferior de desenvolvimento (Tb) foi de 7,13°C e a constante térmica de 188,7GD. Mediante um Sistema de Informação Geográfica, foram obtidos mapas de distribuição do desenvolvimento de T. radiata e D. citri. Assim, ao longo do ano podem ocorrer, na região norte, de 10 a 13 ciclos de D. citri e de 31 a 35 ciclos de T. radiata; na região nordeste, o número de ciclos pode variar de 6 a 10 e de 24 a 31 para a praga e para o parasitóide, respectivamente; nas regiões sudoeste e sudeste, o número de gerações pode variar de 3 a 10 e de 19 a 31 para D. citri e T. radiata. Verificando estes aspectos da interação T. radiata e D. citri, os dados obtidos no presente trabalho poderão auxiliar para a implementação de um programa de controle biológico, como parte do manejo de D. citri, em regiões ecologicamente distintas do estado de São Paulo. / Since 2004, have been detected in citrus-growing areas of São Paulo, the bacterias that are responsible for the main disease of citrus worldwide, known as greening or huanglongbing. The widespread distribution in Brazil of the vector psyllid, Diaphorina citri and the presence of the pathogen in citrus-growing areas is a limiting factor for production. Tamarixia radiata is the most important biological control agent against D. citri. Therefore, the objectives of this study were to: a) conduct a population survey of T. radiata in the citrus-growing regions of the State of São Paulo; b) characterize polychromism in populations of the parasitoid from the main growing regions in the State of São Paulo; c) study the biology of T. radiata under laboratory conditions; d) evaluate the parasitism capacity at different temperatures; e) determine, by means of releases in commercial citrus orchards, the effectiveness of T. radiata for the control of D. citri; f) determine the occurrence and effects on parasitism of the T. radiata - Wolbachia association; g) prepare an agroecological zoning of D. citri and T. radiata for the State of São Paulo based on their temperature and humidity requirements. T. radiata populations collected in Itirapina, Pederneiras, Piracicaba, and São Carlos showed chromatic variations in relation to the typical species; the ITS1 and ITS2 rDNA regions of the populations analyzed had between 98 and 99% identity. Consequently, these chromatic variations are related to the intraspecific phenotypic plasticity characteristic of populations that are undergoing a process of ecological adaptation. In a 24-hour period, the highest parasitism of T. radiata was obtained at 25 and 30°C. This parasitoid developed in the temperature range from 15 to 35°C; the most suitable temperature was 25°C, since it gave the highest viability for the egg-adult period, and the highest net reproductive rate (Ro) and finite rate of increase values (). In the municipality of Araras, T. radiata parasitism percentage values eight days after release remained between 51.57 and 72.75%. In the areas selected in the municipalities of Cordeirópolis and Limeira, the parasitism percentage of T. radiata after three releases ranged between 30 and 60%. The populations collected in Cafelândia, Ribeirão Bonito, and Piracicaba showed multiple infections by Wolbachia. The parasitoids lower temperature development threshold (Tb) was 7.13°C, with a thermal constant of 188.7 GDD. Distribution maps for T. radiata and D. citri development in the State of São Paulo were obtained by means of a Geographic Information System (GIS). According to those, from 10 to 13 D. citri cycles and from 31 to 35 T. radiata cycles may occur in the northern region over the course of one year; in the northeastern region, the numbers of cycles may vary from 6 to 10 and from 24 to 31 for the pest and the parasitoid, respectively; in the southwest and southeast regions the numbers of generations may vary from 3 to 10 and from 19 to 31 for D. citri and T. radiata. Based on these aspects of the T. radiata × D. citri interaction, the data obtained in this work can be useful for the implement a biological control program as part of D. citri management in ecologically distinct regions of the State of São Paulo.
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Prévalence, déterminants et dynamique des arrangements de temps parental postséparation chez les enfants québécois nés à la fin des années 1990

Pelletier, David 09 1900 (has links)
Puisque de plus en plus d’enfants sont exposés à la séparation de leurs parents, plusieurs d’entre eux doivent partager leur temps entre les logements et la supervision de leur mère et leur père. Qu’on nomme cette réalité « garde », « résidence » ou « temps parental », elle complique grandement la description et la mesure des structures familiales dans lesquelles évoluent les enfants. Dans ce contexte, la thèse comporte deux objectifs principaux. Le premier consiste à préciser l’évolution historique des différents concepts légaux et sociologiques en jeu et à montrer comment le flou terminologique entourant la garde entraîne des problèmes lors de la mesure des arrangements résidentiels des enfants. Pour exposer la problématique, je tente de déterminer la prévalence de la double résidence égalitaire en faisant une évaluation critique des sources de données disponibles au Québec et au Canada. En fin de compte, en raison des lacunes de ces diverses sources et de leurs résultats parfois divergents, il s’avère pratiquement impossible de répondre à la question : « Combien d’enfants vivent en garde partagée (ou en double résidence) ? ». Le second objectif, qui occupe la majeure partie de la thèse, vise à illustrer le caractère dynamique des arrangements de temps parental, un aspect souvent ignoré dans la littérature scientifique. À partir des données des treize premiers passages de l’Étude longitudinale du développement des enfants du Québec (ÉLDEQ) (n=2120), je distingue quatre arrangements de temps parental postséparation : 1) la résidence maternelle (avec peu ou pas de contacts père-enfant) ; 2) la résidence maternelle (avec contacts père-enfant réguliers) ; 3) la double résidence ; 4) la résidence paternelle. En ordonnant les informations disponibles à différents points dans le temps pour un même enfant, j’ai pu reconstituer des trajectoires de temps parental complètes. Les analyses réalisées sur ces trajectoires sont rapportées dans deux articles. Je m’intéresse, dans le premier article, aux caractéristiques familiales liées à l’établissement d’un arrangement donné au moment de la séparation ainsi qu’à la durée de cet arrangement. J’y montre par exemple que la part du temps parental assumée par le père au moment de la séparation est positivement associée au niveau de scolarité des parents, au travail à temps plein des mères et au sentiment de plaisir parental des pères. On y constate aussi que les arrangements initiaux ne sont pas tous aussi durables les uns que les autres. Même si les facteurs associés à cette durée sont plus difficiles à discerner, le niveau de scolarité des parents semble être important dans le processus. Dans le second article, je construis des tables de survie multiétats afin de résumer les trajectoires de temps parental de la perspective d’un enfant « moyen ». Je cherche entre autres à déterminer combien de temps les enfants passent dans chacun des quatre arrangements définis plus tôt et à identifier les facteurs sociodémographiques associés à cette répartition. J’y conclus que le temps passé en double résidence par un enfant moyen est faible, mais qu’il augmente avec le niveau de scolarité des deux parents. La double résidence est cependant une composante centrale de la paternité postrupture. Malgré une grande fluidité dans les trajectoires de temps parental, l’arrangement établi au moment de la séparation demeure un bon prédicteur de l’expérience parentale ultérieure. Les enfants initialement en double résidence, par exemple, perdent rarement contact avec leur père au cours des cinq années qui suivent la séparation, et ce, même si plusieurs d’entre eux finiront par habiter principalement avec leur mère. / As more children are exposed to the separation of their parents, many of them have to share their time between the homes and the supervision of their mother and father. Whether this reality is referred to as “custody”, “residence” or “parenting time”, it greatly complicates the description and measurement of the family structures in which children evolve. In this context, the thesis has two main objectives. The first is to clarify the historical evolution of the various legal and sociological concepts involved and to show how the terminological confusion surrounding child custody raises problems when trying to measure children’s living arrangements. In particular, I try to determine the prevalence of egalitarian dual residence by critically assessing the various data sources available in Quebec and Canada. In the end, because of the shortcomings of these various sources and their sometimes divergent results, it is virtually impossible to answer the question: “How many children live in shared physical custody (or dual residence) ?” The second objective, which comprises most of the thesis, aims to illustrate the dynamic nature of parenting-time arrangements, an element often overlooked in the scientific literature. With data from the first thirteen waves of the Quebec Longitudinal Study of Child Development (QLSCD) (n = 2120), I distinguish four postseparation parenting-time arrangements: 1) mother residence (with little or no father-child contact); 2) mother residence (with regular father-child contact); 3) dual residence; 4) father residence. By ordering the information available at different time points for each child, I was able to reconstruct complete parenting-time trajectories. The analyzes carried out on these trajectories are reported in two articles. In the first article, I look at family characteristics related to the establishment of specific arrangements at separation and at the duration of this arrangement. For instance, I show that the share of parenting time assumed by fathers following separation is positively associated with parents’ education level, mothers’ full-time employment and father’s feeling of parental enjoyment. The article also shows that initial arrangements are not all as durable as each other. Although the factors associated with this duration are difficult to identify, the parents’ level of education appears to be play an important role. In the last article, I build multistate life tables in order to summarize parenting-time trajectories from the perspective of an average child. I try to determine, inter alia, how much time children spend in each of the four arrangements defined earlier and what sociodemographic factors are associated with this distribution of time. I show that time spent in dual residence by an average child is low, but that it increases with the education level of both parents. Dual residence is, however, a central component of postseparation fatherhood. Despite great fluidity in parenting-time trajectories, arrangements established at separation remain good predictors of the subsequent parenting experience. Children initially in dual residence, for instance, seldom lose contact with their father during the first five years following separation even if many of them eventually end up living mainly with their mother.
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臺灣地區婚姻狀態別預期壽命變遷 / Change of marital status life expectancy in Taiwan

蔣侃學, Chiang ,Kan Hsueh Unknown Date (has links)
臺灣地區近五十年來的人口結構,在婚姻組成上有著相當大的變化。婚姻組成的改變,除了一方面作為瞭解過去社會變遷的重要指標外,對於未來的生育率、勞動力及人口結構等重要事件,都會產生根本性的影響,是瞭解社會變遷的重要指標之一。此外,婚姻組成的改變,背後蘊含的,是臺灣社會對於婚姻的想像及態度的變遷。由於婚姻生活對於個人生命歷程,有著絕對關鍵性的影響,故而,對於婚姻的態度,也直接改變了人們對於自身生命歷程的想像。也正因為如此,對於婚姻組成狀態以及婚姻生命歷程的分析與理解,是作為瞭解臺灣社會變遷的重要參考指標,也正是構成本論文研究的核心議題。 前輩學者在討論類似議題時,採用的方法,乃是透過估算各婚姻狀態(未婚、離婚、有偶、喪偶、死亡)間的轉移率,建構多重狀態遞增遞減婚姻生命表,以理解婚姻的生命歷程變化。 然而,此一方法雖然可以提供我們相當多關於婚姻生命歷程變遷的訊息,卻由於資料的難以取得,使得在估算的結果上,各學者間莫衷一是、無有定論。有鑑於此,在探討此一問題時,本研究不採取上述的路徑,而是採用目前在學界公認較為穩定的估算方法--「蘇立文法」。此法雖然透露的訊息,不如多重狀態遞增遞減婚姻生命表來得豐富,卻可以提供我們對於各婚姻狀態別預期壽命相對穩定且可靠的訊息。 在上述討論的脈絡下,本研究以「蘇立文法」,透過1956、1966 、1980、1990、2000年五次的普查資料,配合相對應年度的「國民生命表」,建構這五個年度的「年齡別婚姻生命表」,企圖勾勒臺灣地區近五十年來婚姻生命歷程的變遷。 本論文研究的結果發現,隨著預期壽命的不斷延長,臺灣地區人口處於未婚的預期時間不斷增加,未婚佔其一生壽命的比例也持續上升。同時,離婚的預期時間增加,喪偶的預期時間減少,顯示人們一生中處於鰥寡狀態的比例下降。而可能造成婚姻解組的主要風險,從過去的「喪偶」轉變為「離婚」。另外值得注意的是,雖然未婚、離婚的預期時間增加,生命中總共處於有偶狀態的比例,卻幾乎沒有下降。顯見未婚時間的延長,代表的不是人們不進入婚姻,而是「延後進入婚姻」;離婚時間延長,不是人們從此處於單身,而是很可能透過再婚,再次進入婚姻狀態。 承上所述,本研究發現,由於晚婚、離婚、不婚、再婚等等現象的盛行,過去集中且單一的適婚年齡,開始變得分散、延後。人們可能進入婚姻的時間,不僅僅限於過去的「三十大關」,而是整個的延後。同時,婚姻的歷程,不再如過去單一且穩定的「未婚-有偶-(喪偶)-死亡」,而是像「未婚-(有偶)-(離婚)—(再婚)-(喪偶)-(有偶)-(喪偶)-死亡」一般,呈現相對多元、複雜的婚姻生命歷程。

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