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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

Diversidade de ácaros edáficos em um fragmento de mata atlântica e três cultivos agrícolas, em Jaboticabal/SP, com ênfase nos Gamasina (Mesostigmata) / Diversity of edatic mites in an atlantic forest fragment and three agricultural crops, in Jaboticabal / SP, with emphasis in the Gamasine (Mesostigmata)

Junqueira, Barbara Rodrigues 31 October 2017 (has links)
Submitted by BARBARA RODRIGUES JUNQUEIRA null (barbararodriguesj@hotmail.com) on 2017-12-13T12:08:30Z No. of bitstreams: 1 Dissertação_Barbara_Rodrigues_Junqueira (1).pdf: 4886045 bytes, checksum: acd676ff2d3642858699d8bc8b2f628e (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2017-12-13T13:15:16Z (GMT) No. of bitstreams: 1 junqueira_br_me_jabo.pdf: 4886045 bytes, checksum: acd676ff2d3642858699d8bc8b2f628e (MD5) / Made available in DSpace on 2017-12-13T13:15:16Z (GMT). No. of bitstreams: 1 junqueira_br_me_jabo.pdf: 4886045 bytes, checksum: acd676ff2d3642858699d8bc8b2f628e (MD5) Previous issue date: 2017-10-31 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / No Brasil, os estudos que visam avaliar a diversidade e abundância de ácaros edáficos predadores, como os Gamasina (Mesostigmata), ainda são incipientes, focando principalmente em áreas de vegetação natural. No entanto, compreender o impacto da agricultura nestes organismos é importante no aspecto de preservar a biodiversidade e avaliar a sensibilidade destes indíviduos aos tratos culturais. Além disso, conhecer a diversidade desses ácaros edáficos é o primeiro passo na prospecção de novos agentes de controle biológico. Dessa forma, o objetivo dessa dissertação foi determinar e comparar a diversidade e abundância de espécies de ácaros edáficos presentes em um fragmento de Mata Atlântica e em três cultivos agrícolas, em Jaboticabal, estado de São Paulo, com ênfase nos Gamasina. As coletas de solo e serrapilheira (quando presente) foram realizadas bimenstralmente, entre os meses de agosto de 2015 a junho de 2017. Foram avaliadas quatro áreas: um fragmento de Mata Atlântica e cultivos de milho, soja e mangueiras. Cada coleta consistiu em 10 pontos amostrais aleatórios. No laboratório, as amostras foram colocadas em equipamento do tipo Funil de Berlese-Tullgren modificado para extração dos ácaros. O material extraído foi triado, os ácaros foram separados por ordem, sendo os Gamasina montados em lâminas de microscopia. Em seguida, os Gamasina foram identificados, sempre que possível, até o nível de espécie. Os resultados deste estudo demonstraram que o grupo de ácaros edáficos mais abundante, para as quatro áreas de coleta, foi Oribatida (Sarcoptiformes), representando 73,5% dos ácaros coletados. Os Gamasina foram o segundo grupo mais encontrado (19%). Dentre os Gamasina foram encontradas 12 famílias, 35 gêneros e 50 morfoespécies, com destaque para Ologamasidae, representando 33,9% dos Gamasina coletados, seguida de Blattisociidae (18,3%), Laelapidae (13,2%) e Phytoseiidae (11,8%). No fragmento de vegetação natural foram coletados cerca de 52% dos Gamasina, com 25% no cultivo de mangueira, 19% na soja e 4% no milho. A área de vegetação natural também foi a que apresentou maior diversidade de gêneros e morfoespécies seguido pelo cultivo de mangueiras, soja e milho. Nesse estudo também foram encontradas novas espécies para ciência e até um novo gênero, Ologamasidae n. gen. n. sp., que é descrito baseado na morfologia de fêmeas e machos adultos coletados no fragmento de Mata Atlântica. Esse estudo demonstra que o impacto da ação antrópica afeta a comunidade de ácaros edáficos qualitativa e quantitativamente, ou seja, nas áreas de cultivo agrícola obteve-se menor diversidade e abundância de Gamasina. / In Brazil, studies aimed to evaluate the diversity and abundance of edaphic predatory mites, such as the Gamasina (Mesostigmata), are still incipient, focusing mainly on areas of natural vegetation. However, understanding the impact of agriculture on these organisms is important in terms of preserving biodiversity and assessing the sensitivity of these individuals to agricultural managements. In addition, knowing the diversity of these soil mites is the first step in prospecting for new biological control agents. Thus, the objective of this study was to determine and compare the diversity and abundance of edaphic mite species present in a fragment of Atlantic Forest and three agricultural crops, in Jaboticabal, state of São Paulo, with an emphasis on Gamasina. Soil and litter (when present) were collected bi-monthly, between August 2015 and June 2017. Four areas were evaluated: a fragment of Atlantic Forest, corn, soybean and mango crops. Each sample consisted on ten random sampling points. In the laboratory, the samples were placed in a modified Berlese-Tullgren funnel for the extraction of mites. The extracted material was screened and the mites were separated in order, the Gamasina being mounted on microscopic slides. Then were identified, when possible, to species level. The results of this study showed that Oribatida (Sarcoptiforme) was the most abundant mite collected, representing 73.5% of total miltes, for the four areas. Gamasina were the second most abundant group (19%). Among the Gamasina, 12 families, 35 genera and 50 morphospecies were found, mainly Ologamasidae, representing 33.9% of the Gamasina collected, followed by Blattisociidae (18.3%), Laelapidae (13.2%) and Phytoseiidae (11, 8%). In the natural vegetation fragment, about 52% of the Gamasina were collected, 25% in mango culture, 19% in the soybean area and 4% in the corn area. The area of natural vegetation was also the one that presented greater diversity of genera and morphospecies followed by the cultivation of mango, soybean and corn. In this study new species were also found for science and even a new genus, Ologamasidae n. gen. n. sp., which is described based on the morphology of adult females and males collected in the Atlantic Forest fragment. This study demonstrates that the impact of anthropic action affects the community of soil mites qualitatively and quantitatively, that is, in the agricultural cultivation areas, there was less diversity and abundance of Gamasina. / 134530/2015-2
32

The cognitive dimensions of a biological hazard: A study of livestock predation in British Columbia within a hazards framework

Wilkerson, Orland Lee 29 June 2018 (has links)
This study focuses on the cognitive dimensions of two important aspects of the predator-livestock problem in British Columbia: the concrete coping strategies adopted by individual livestock producers and the institutional responses adopted by, or available to, the Provincial Wildlife Branch. The threat posed to domestic stock by wild predators is conceptualized as a biological hazard, and the advantages of this approach are discussed. A conceptual framework integrating theoretical insights from geography, social psychology, psychology, and political science is developed. Several hypotheses are derived from this framework, and a number of these are linked to form two conceptual models, one designed for an analysis of ranchers' cognitions, the other for the examination of nonranchers' cognitions. Both models relate several cognitive variables to the perceived acceptability of a number of lethal methods of wolf control. These variables include: ecological orientation (as measured by the New Environmental Paradigm Scale); attitudes towards wolves; and perceptions of the wolf threat. Two mail survey questionnaires were developed, one (Version A) for nonranchers, the other (Version B) for ranchers. Version A was satisfactorily completed by a total of 574 respondents: 259 from the city of Victoria; 95 from Williams Lake; 87 from Kamloops; and 133 from the Northwest Wildlife Preservation Society (NWWPS). The data from the three urban samples were combined to form a "general public" sample. Version B was completed by 283 ranchers. Questionnaire data were supplemented by the content analysis of several relevant documents and informal interviews with selected personnel from the B.C. Wildlife Branch, the ranching community, and a number of wildlife interest groups. A variety of statistical techniques, including simple correlation, multiple regression, analysis of covariance, and discriminant analysis, were used to analyze the data. The analyses provided strong support for most of the hypotheses. Several of the more important findings are noted here. For all three sample groups (general public, ranchers, and NWWPS), significant relationships were found between ecological orientation and attitudes towards wolves; between attitudes towards wolves and perceptions of the threat that wolves pose to individual cattle producers and the cattle industry as a whole; between attitudes towards wolves and the acceptability of certain lethal wolf control measures; and for nonranchers, between attitudes towards wolves and the perceived humaneness of lethal wolf control, and between the perceived humaneness of lethal wolf control and the acceptability of lethal wolf control. A number of variables exhibited significant differences across the groups: ecological orientation; attitudes towards woIves; and perceptions of the wolf, coyote, and bear threats. Several management implications suggested by the research are discussed and a number of policy recommendations and suggestions for further research are offered. / Graduate
33

Dinâmica populacional e comportamento predatório individual da aranha social Parawixia bistriata (Rengger) (Araneae: Araneidae) /

Barbieri, Eduardo Feltran. January 2005 (has links)
Orientador: José Chaud Netto / Banca: Edilson Divino de Araújo / Banca: Sulene Noriko Shima / Parawixia bistriata é a única espécie da família Araneidae que apresenta comportamento social. Refúgio comunal e cooperação de caça são duas características interessantes observadas nessa espécie. O presente trabalho teve como objetivos analisar a dinâmica populacional das colônias de Parawixia bistriata durante seu desenvolvimento e estudar o comportamento de caça individual das aranhas dessa espécie. Por meio de observações de campo de sete colônias de Parawixia bistriata foi possível verificar que estas passaram por um intenso processo de forrageio, bem como de procura por um hábitat ideal, na medida em que se observa uma constante mudança no local de construção do refúgio comunal. Durante esse processo de forrageio, devido à deficiência na quantidade de recursos, bem como de espaço físico, é comum observar fissões de colônias dessa espécie. Em experimentos realizados na presente pesquisa observou-se que, apesar de ocorrer decréscimo acentuado no número de indivíduos em algumas colônias, a razão sexual das mesmas não foi alterada (1:1) no período em que foi realizada a sexagem dos indivíduos. Também foi observada uma grande tolerância entre indivíduos coespecíficos não aparentados, ou seja, de colônias não irmãs. Essa aceitação confirma a significativa existência de fusões de colônias durante o desenvolvimento dos indivíduos dessa espécie, que reforçam a idéia da formação das super-colônias, mencionada anteriormente por outros autores. No que diz respeito ao comportamento de caça individual em colônias dessa mesma espécie de aranha orbitela, observou-se que estas aranhas conseguem, de certa forma, escolher um determinado tipo de presa. Isso ocorre na medida em que se observa o total desprezo pelas presas de pequeno porte, bem como a preferência pela captura de presas de tamanho grande. Um outro fator importante é o fato de que essas... (Resumo completo, clicar acesso eletrônico abaixo) / Parawixia bistriata is the unique species of Araneidae that shows social behaviour. Communal refuge and cooperative hunting are two interesting features observed in this species. The objectives of this research were to analyze the population dynamics in colonies of Parawixia bistriata and to study the individual predatory behaviour of this species. Field observations of seven colonies of Parawixia bistriata showed that these colonies developed an intense hunting activity and search for an ideal place to build the nest. During these two activities the colonies can separate its members on account of the lack of food or space to build their webs. Although the number of spiders is significantly reduced during the development in some colonies, this research showed that the sex ratio of the colonies is almost 1:1 when it is possible to do the sexual identification. It was also noted that there is a great tolerance between spiders from different colonies and because of this there are fusions of colonies that become supercolonies. In relation to the individual predatory behaviour in Parawixia bistriata it was possible to see that this spider can recognize and choose its prey. Another experiment of this research showed that the spiders refused a small prey or left it after a while, if a bigger prey was captured. It was also observed that the spider "prefers" a big prey than a small one, and the spider feeds on a big prey in the same place of the web where it was caught. This fact can be explained by the existence of intra colonial competition for food and this behaviour maybe is a strategy to avoid the robbery of food by a co-specific that lies beside it / Mestre
34

Voluntold: tactics in U.S. Army enlisted recruitment

Houghton, Helen Grace 18 October 2020 (has links)
The maintenance of the size and strength of the U.S. volunteer military heavily depends on its recruitment arm to prospect and inform potential recruits. In a country where military service is believed to offer benefits such as steady incomes and college education to disadvantaged communities while implying they are unavailable through other means the concern becomes that recruiters target these communities for recruitment. This thesis first draws on the existing literature about citizen-state interactions to derive a new theoretical perspective about predatory practices then begins to evaluate that theory through a qualitative analysis of military recruitment manuals. The findings suggest that predatory practices may be occurring at lower levels of the recruitment hierarchy and those in charge are aware and unable or unwilling to prevent it.
35

Diversidade de ácaros edáficos Gamasina (Mesostigmata) no bioma Caatinga no estado de Alagoas, com descrição de uma espécie nova, e elaboração de um catálogo para a família Podocinidae /

Barros, Ávyla Régia de Albuquerque January 2020 (has links)
Orientador: Gilberto José de Moraes / Resumo: No Brasil, o estudo da diversidade da acarofauna edáfica ainda é pouco conhecido e restrito principalmente a áreas de vegetação natural. Raros estudos têm sido conduzidos em áreas agricultáveis. Na Caatinga do estado de Alagoas não existe, até o momento, nenhum trabalho que busque compreender os impactos que as práticas agrícolas possam exercer sobre a diversidade e abundância da fauna de ácaros Gamasina (Mesostigmata). Os estudos de diversidade são interessantes do ponto de vista aplicado e conservacionista, visto que correspondem ao primeiro passo para compreensão dos sistemas, fornecendo base para desenvolvimento de outros trabalhos. Desta forma, com esse estudo objetivou-se realizar um inventário das espécies de ácaros edáficos, com ênfase nos Gamasina, no bioma Caatinga, em um fragmento de vegetação natural, em dois cultivos agrícolas e uma área de pastagem, em Olho d’ Água das Flores, estado de Alagoas, buscando compreender quais os possíveis impactos que as áreas agricultáveis podem exercer sobre a população dos Gamasina. As coletas foram realizadas a cada três meses, durante um ano (dezembro de 2018 a agosto de 2019). De cada área e em cada coleta foram tomadas 16 amostras de solo (0-5 cm de profundidade). O material extraído foi triado e os ácaros Gamasina foram montados em lâminas com meio de Hoyer, divididos em morfoespécies e identificados, sempre que possível, até o nível de espécie. Os ácaros dos outros grupos foram apenas contabilizados. A análise dos dados foi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In Brazil, the study of the diversity of mite fauna is still incipiente and restricted mostly to areas of natural vegetation. Rare studies have been conducted in agricultural areas. In the Caatinga of Alagoas state, no work has been conducted to understand the impacts that agricultural practices may have on the diversity and abundance of the edaphic mite fauna. Diversity studies are interesting from applied and conservationist points of view, as they are the first step in understanding systems, providing a basis for the development of other works. Thus, this study aimed to carry out an inventory of edaphic mite species, with emphasis on Gamasina (Mesostigmata), in a fragment of natural vegetation the Caatinga biome, two agricultural crops and a pasture area, in Olho d 'Água das Flores, seeking to understand the possible impacts that agricultural areas can have on the population of Gamasina. Samples went collected every three months between December 2018 and August 2019. At each sampling date, 16 soil samples were taken from each area (0-5 cm deep). The extracted material was examined and the Gamasina mites were mounted on slides using Hoyer's medium, divided into morpho-species and identified, whenever possible, at the species level. Data analysis was performed using the PAST and ANAFAU programs, in addition to the quantitative analysis of the Euclidean cluster. The results obtained indicate that the greatest abundance of Gamasina mites was found in natural vegetation, follow... (Complete abstract click electronic access below) / Mestre
36

Faculty Applicants’ Attempt to Inflate CVs Using Predatory Journals

Pond, Brooks B., Brown, Stacy D., Stewart, David W., Roane, David S., Harirforoosh, Sam 01 February 2019 (has links)
Recently, scientific publishing has experienced an expansion of journals and publishers whose primary goal is profit and whose peer review process is virtually non-existent. These “predatory” or “opportunistic” journals pose a threat to the credibility and integrity of legitimate scientific literature, and quality science. Unfortunately, many scientists choose to publish in these journals and/or serve on their editorial boards, either due to ease of rapid publication or naivety. Here, we highlight the extensive use of predatory publications or editorial board involvement by applicants applying for a faculty position in the Pharmaceutical Sciences department at the Bill Gatton College of Pharmacy at East Tennessee State University. We caution search committees at other pharmacy schools to thoroughly examine applicant curricula vitarum (CVs) for predatory publishing.
37

Defining Predatory Mortgage Lending in Utah: A Professional's Perspective

Erickson, Luke V. 01 May 2006 (has links)
The purpose of this study was to define and describe the nature of predatory mortgage lending in the state of Utah . Twelve professionals from the state who work in the mortgage lending market participated. Data consisted of interviewee comments and were analyzed qualitatively using a multi-step method of coding for concepts and themes. Through coding and analysis it was determined that the term predatory mortgage lend ing is defined as an act of abuse that is targeted towards a borrower with one or more vulnerable characteristics. It was al so found that users of this term do not always adhere to this strict definition, but rather use it as a catch-all term for any general mortgage abuse, rather than only for those that are targeted. The term is al so used when referring to instances of fraud, and nearly all other forms of unfair lending. To help increase the measurability of predatory lending, the interviews also gave descriptive detail in terms of its magnitude, underlying factors, commonly occurring practices, victim characteristics, impacts, and suggestions for reduction. Suggestions for reduction of predatory lending include increasing accountability of actors, both legally and by the industry itself bridging state and national jurisdictional gaps, and increasing fun ding for consumer education and neighborhood revitalization. Education was especially emphasized as a tool for preventing occurrences of predatory mortgage lending. not only in the form of pre-homebuyer education but especially in the form of financial education as a requirement in the public school s, beginning at a very young age.
38

The predatory behavior of Pisaster ochraceus (Brandt)

Jillson, David A. 01 January 1973 (has links) (PDF)
The persistence of predator-prey systems in evolutionar time is a function of the efficiency with which the predator obtains its food, and the ability of the prey to avoid ex- tinction. One of the important components of survival of the system is environmental heterogeneity (Huffaker 1958). Along rocky intertidal regions of the northern Pacific coast of North America, a major predator, the starfish Pisast ochraceus has a dominant effect upon patterns of distribution of many intertidal organisms (Paine 1966). Likewise, the distribution of intertidal fauna exert an effect upon the activities of Pisaster. Other biological interactions such an grazing activities of limpets and predatory behavior of emails also affect the intertidal distribution of species (Connell 1961, 1970, Dayton 1971).
39

BIVALVE EPIBIONT ARMOR: THE EVOLUTION OF AN ANTIPREDATORY STRATEGY

JONES, DONNA CARLSON 01 July 2004 (has links)
No description available.
40

The effects of two foraging traits on within-plant foraging efficiency of Phytoseiulus persimilis (Acari: phytoseiidae)

Smith, Ian A. January 1900 (has links)
Master of Science / Department of Entomology / David C. Margolies / James R. Nechols / Many crops grown in greenhouses are damaged by the twospotted spider mite, Tetranychus urticae. The predatory mite, Phytoseiulus persimilis, is a commercially-available predator that is commonly used to control twospotted spider mites on greenhouse crops; but its efficacy varies among crops, and it is generally ineffective at low prey densities. In general, predator foraging efficiency depends on how well predators find prey patches, the length of stay in prey patches, and consumption of prey while in prey patches. With respect to P. persimilis, I asked how this predator responds to different prey distributions, as might be encountered at different stages of spider mite infestations. I also asked how components of foraging, namely consumption rate and dispersal tendency, affected predator efficiency. To examine the former, I established T. urticae eggs on 6-leafed cucumber plants in two distributions. To examine the latter, I imposed artificial selection on a population of P. persimilis to create a line that exhibited extremely high consumption and one that demonstrated a greater tendency for dispersal. Subsequently, foraging efficiency was assessed by observing predator oviposition and consumption of twospotted mite eggs on individual leaves of 6-leafed cucumber plants. The number of eggs laid by predators corresponded to the number of prey consumed regardless of predator line. In addition, predators from both lines distributed their eggs proportional to where they fed. However, prey consumption differed between selected lines in response to prey distribution. Predators selected for high consumption fed more on the basal leaf where they were released; whereas prey consumption by the high dispersal and control lines were more evenly distributed throughout the plant. These results contribute to a better understanding of how foraging behavior is modified in plant landscapes under different levels of expression of foraging traits. They also indicate that predator release strategies likely would need to modified in accordance with the kind of foraging trait(s) used in artificial selection programs. In general, my research, when combined with future studies at a broader landscape level, will facilitate decisions by biological control practitioners about whether changes in foraging efficiency resulting from artificial selection justify the cost investment of producing selected lines of P. persimilis

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