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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

Trait Anxiety and Other Personality Constructs as Predictors of Negative Reactions to Quarantine and Social Isolation

Ambrose, Faith A 01 January 2020 (has links)
Former research has shown a strong relationship between anxiety and various negative reactions to trauma, including widespread traumatic events such as natural disasters, war, and pandemics. COVID-19 has been an ongoing, potentially traumatic event for individuals all over the world. Even individuals who have not experienced serious traumatic consequences because of the pandemic have likely had some negative experiences regarding the mandated quarantine and social distancing. This study seeks to find possible personality predictors for negative reactions, whether they be behavioral or cognitive. Participants completed several questionnaires that test personality constructs, including trait anxiety, need for affiliation, extraversion, and autonomy. Following this, the participants completed a questionnaire divided into two subscales evaluating cognitive and behavioral reactions to quarantine, developed from the list of immediate and delayed reactions to trauma created by the Center for Abuse Treatment in the United States. The most significant finding from this study is the correlation between these negative reactions- both cognitive and behavioral- and trait anxiety. Along with this, extraversion was found to correlate with negative behavioral reactions, and a need for affiliation was found to correlate with negative cognitive reactions. Each item within the reactions scale was tested in correlation with these three constructs which showed significance. These items provide implications that could potentially allow us to prevent these negative thoughts and behaviors provided that the pandemic continues extensively or in the event that another widespread traumatic event occurs in the future.
32

Phenology, impact, and rearing of Lycorma delicatula (White) (Spotted Lanternfly) in Virginia

Dechaine, Andrew C. 02 April 2021 (has links)
The spotted lanternfly, Lycorma delicatula (White) (Hemiptera: Fulgoridae), is a new invasive insect from Asia that is currently spreading in the Mid-Atlantic region of the US, where it has become a pest of economic concern for many industries in their invaded range. The purpose of this research was to document L. delicatula phenology in Virginia, their feeding impact to trees, and to test a rearing protocol in quarantine laboratory conditions. First, using field plots and weekly observational surveys, L. delicatula phenology was documented in 2019 and 2020 in Winchester, Virginia. I showed that L. delicatula were active from late April into November for each sampling year, and that the timing of life stage events varied only slightly between years. I also calculated cumulative average growing degree days for each life stage event using a lower developmental threshold of 10°C. Additionally, I confirmed that the host range of L. delicatula narrows as they progress through development. These results will help growers and land managers develop integrated pest management plans targeting L. delicatula. Second, dendrochronological methods were used to quantify L. delicatula feeding injury to Ailanthus altissima (Miller) Swingle (Sapindales: Simaroubaceae), Juglans nigra L. (Fagales: Juglandaceae), and Liriodendron tulipifera L. (Magnoliales: Magnoliaceae). Two sites in Pennsylvania that have experienced high populations and heavy feeding pressure from L. delicatula since 2016 were used to collect tree cores for analysis. I found evidence suggesting L. delicatula is capable of reducing the growth of A. altissima, but did not find the same evidence in the wood of the other tree species tested. Additionally, I found evidence that systemic insecticide treatments may reduce or prevent damage to A. altissima fed on by L. delicatula. Additional dendrochronological studies on the damage inflicted by L. delicatula feeding could shed light on the long-term impact of this new invasive tree pest. Lastly, a protocol for rearing L. delicatula was tested inside Virginia Tech's Insect Quarantine Laboratory. Three different cuttings of A. altissima (apical meristems, epicormic shoots, and field collected foliage) were tested to determine the best food source for L. delicatula in quarantine laboratory conditions. Overall, I did not find a significant difference between food treatments, however a greater proportion of third instars developed into fourth instars in the apical meristem treatment. I suggest future L. delicatula rearing research include the use of potted plants and/or multiple species. Though I had low success in rearing adult L. delicatula to produce egg masses, this method may prove useful for rearing early instars from eggs or sustaining field collected specimens for short durations. Research expanding our knowledge of L. delicatula will help us reach our goal of more effectively managing this pest species in the future. / Master of Science in Life Sciences / The spotted lanternfly, Lycorma delicatula (White), is a new invasive pest species impacting the eastern and northeastern regions of the United States. This insect uses its straw-like mouth parts to feed on the sap of many different plants including fruit trees, grapes, and several important ornamental and timber trees. Though they do not bite or sting, feeding can result in wilting, the growth of sooty mold, and sometimes plant mortality, making them an economic and nuisance pest in their invaded range. This research primarily focused on studying the timing of the spotted lanternfly's life cycle, feeding impact to trees, and a method for raising them in the laboratory for research purposes. The life-cycle of the spotted lanternfly was documented over two growing seasons in Winchester, VA and the timing of each life stage was shown to be similar between years. Additionally, it was confirmed that the spotted lanternfly feeds on fewer host species as it develops into an adult. Tree-ring analysis was used to identify spotted lanternfly feeding injury to tree-of-heaven, black walnut, and tulip poplar. I found evidence suggesting spotted lanternfly feeding can cause reduced growth in tree-of-heaven, but did not find similar evidence in the other species tested. A laboratory colony of spotted lanternflies would prove beneficial for additional research on this insect. I tested three different types of branches cut from the tree-of-heaven to identify the best food source for spotted lanternfly in laboratory conditions. The findings of this research will help develop pest management strategies to reduce the impact of this new pest in the US.
33

Energy Reserves in Native Freshwater Mussels (Bivalvia:Unionidae) with and without Attached Zebra Mussels: Effects of Food Deprivation

Patterson, Matthew Alan 16 June 1998 (has links)
This project evaluated the feasibility of salvaging zebra mussel-infested freshwater mussels from their native habitat by determining 1) how zebra mussel infestation affects unionid feeding and body condition, 2) how starvation in quarantine affects body condition of unionids, and 3) what feeding regime maintain unionid condition in quarantine. The effects of zebra mussel infestation on two mussel species were evaluated through glycogen analyses of mantle tissue and gut content analysis. Specimens of Amblema p. plicata (Say, 1817) and Quadrula p. pustulosa (I. Lea, 1831), collected from a heavily infested reach of the Ohio River in 1996, had significantly lower (p<0.05) glycogen levels than specimens collected from a low-infestation reach upstream. In 1996 and 1997, heavily infested Amblema p. plicata and Quadrula p. pustulosa had significantly less (p<0.01) organic matter and fewer algal cells in their guts than lightly infested specimens. In addition, gut contents of individual A. p. plicata contained significantly less (p<0.05) organic matter and fewer algal cells than the combined gut contents of all zebra mussels (18-33 mm in length) attached to their shells. Gut analyses also revealed significant diet overlap between native unionids and infesting zebra mussels. Thus, competitive interactions or interference by zebra mussels likely reduced unionid ingestion and consequently reduced glycogen stores. During quarantine, unionids salvaged from a lightly infested area and starved for 30 days had glycogen levels that declined dramatically. After 30 days without supplemental feeding, mean glycogen levels of A. p. plicata declined 85%, and mean glycogen levels of Q. p. pustulosa declined 70%. Thus, feeding of unionids is necessary to maintain their condition during lengthy quarantine. To determine the best feeding regime for unionids in quarantine, assimilation efficiencies and carbon budgets were established for the rainbow mussel, Villosa iris (Lea, 1829), using radio-labelled cultures of Neochloris oleoabundans (Chantanachat and Bold 1962) at three cell concentrations. Assimilation efficiencies for Villosa iris at 100,000cells/ml, 10,000 cells/ml, and 1,000 cells/ml were similar (45-56%); however, regardless of these similarities, assimilation efficiencies from this study indicate that Neochloris oleoabundans is readily assimilated (~50% AE) by Villosa iris . In addition, total assimilation was maximized at 100,000cells/ml, which indicates that Villosa iris has the greatest amount of energy available for growth, reproduction, and maintenance of condition in captivity at this cell concentration. During a second quarantine experiment, specimens were provided with 100,000cells/ml of N. oleoabundans twice per day. Initial mean glycogen levels for Amblema p. plicata (9.4 + 2.4 mg/g) and Quadrula p. pustulosa collected from ORM 175.5 in July 1997 were not significantly different (p>0.3) than the mean glycogen levels of A. p. plicata and Q. p. pustulosa collected from the same site in July 1996. Glycogen stores of unionids entering quarantine, therefore, were similar in both the starvation and controlled feeding experiments. After 7, 14, and 30 days of controlled feeding in quarantine, mean glycogen levels of A. p. plicata and Q. p. pustulosa did not change significantly (p>0.1). Thus, quarantine protocol for salvaged native mussels should include the feeding of algae to captive specimens to sustain glycogen levels prior to relocation. / Master of Science
34

Optimizing quarantine regions through graph theory and simulation

Carlyle, Kyle R. January 1900 (has links)
Master of Science / Department of Industrial & Manufacturing Systems Engineering / Todd W. Easton / Epidemics have been modeled mathematically as a way to safely understand them. For many of these mathematical models, the underlying assumptions they make provide excellent mathematical results, but are unrealistic for practical use. This research branches out from previous work by providing a model of the spread of infectious diseases and a model of quarantining this disease without the limiting assumptions of previous research. One of the main results of this thesis was the development of a core simulation that rapidly simulates the spread of an epidemic on a contact network. This simulation can be easily adapted to any disease through the adjustment of many parameters. This research provides the first definition for a quarantine cut and an ellipsoidal geographic network. This thesis uses the ellipsoidal geographic network to determine what is, and what is not, a feasible quarantine region. The quarantine cut is a new approach to partitioning quarantined and saved individuals in an optimized way. To achieve an optimal quarantine cut, an integer program was developed. Although this integer program runs in polynomial time, the preparation required to execute this algorithm is unrealistic in a disease outbreak scenario. To provide implementable results, a heuristic and some general theory are provided. In a study, the heuristic performed within 10% of the optimal quarantine cut, which shows that the theory developed in this thesis can be successfully used in a disease outbreak scenario.
35

Proposta de implantação de programa de plasma de quarentena na Hemorrede Pública de Santa Catarina / Proposed implementation of quarantine plasma program in Public Blood network Santa Catarina

Jacques, Liliane Wendling 30 April 2015 (has links)
Em todo serviço de hemoterapia, a questão da segurança transfusional gera grande preocupação, visto que não existe transfusão isenta de risco de contaminação. Este trabalho tem como objetivo sugerir ao Centro de Hematologia e Hemoterapia do estado de Santa Catarina (HEMOSC), uma proposta de programa de uso de plasma de quarentena visando a segurança transfusional. O plasma de quarentena é aquele originado de um doador de repetição, que apresentou todos os testes sorológicos para doenças hemotransmissíveis não reagentes em doação anterior, até que o doador realize uma nova doação, este hemocomponente é mantido em quarentena, evitando o uso do mesmo em período de janela imunológica. Se todos os testes laboratoriais exigidos pela legislação vigente mantiverem-se não reativos após a nova doação, a unidade de plasma é liberada para uso. Sugere-se adequações no sistema de informática, referentes a triagem clínica e processamento do sangue, especificações para armazenamento e congelamento de plasma. Após análise da produção de plasma da hemorrede catarinense nos anos de 2012 e 2013, foi possível constatar que a instituição apresenta grande potencial para implantação da proposta, sendo necessário adequações na área física dos setores de processamento da hemorrede / Throughout the hemotherapy service, the question of transfusion safety generates great concern, whereas there is no free risk transfusion of contamination. This work aims to suggest to the Center of Hematology of the state of Santa Catarina (Hemosc) a proposal for use of quarantine plasma program to transfusion safety. The quarantine plasma that is originated from a donor replay, which showed all the non-reactive serologic tests for diseases transmissible by blood previous donation until the donor make a new donation, the blood component is kept in quarantine, avoiding the use of it in window periods. If all laboratory tests required by law are kept non-reactive after the new donation, the plasma unit is released for use. To implement the program for this product, adjustments in the computer system, related to recruitment, clinical screening, processing of blood, and specifications for storage and freezing of plasma is needed. After analysis of plasma production in Santa Catarina in 2012 and 2013, we acknowledge that the institution has a great potential for deployment of the proposal, being necessary adjustments in the physical area of the sectors of processing of the HEMOSC
36

Determinação das doses letais e esterilizantes de radiação gama para todas as fases do ciclo evolutivo de Ecdytolopha aurantiana (Lima, 1927) (Lepidóptera: Tortricidae) bicho-furão-dos-citros, visando o seu controle / Determination of lethal and sterilizing doses of gamma radiation for all phases of the life cycle of Ecdytolopha aurantiana (Lima, 1927) (Lepidoptera: Tortricidae) borer of the citrus, aiming its control

Piero, Edson Antonio Di 18 November 2016 (has links)
O objetivo do trabalho foi determinar as doses letais e esterilizantes de radiação gama para todas as fases do ciclo evolutivo de Ecdytolopha aurantiana (Lima, 1927) (Lepidóptera: Tortricidae) bicho-furão-dos-citros, visando o seu controle. O trabalho foi conduzido no Laboratório de Raiobiologia e Ambiente/Radioentomologia do Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, da Universidade de São Paulo (USP). Para irradiação de todas as fases do inseto foi utilizado uma fonte de Cobalto-60, tipo Gammabeam - 650, as doses utilizadas foram: 0 (controle), 50, 100, 200, 300, 400 e 500 Gy, foram irradiados sob uma taxa de dose de 1,112 kGy/hora. Os ensaios foram realizados em câmara climatizada com temperatura de 25 ? 2?C e umidade relativa de 70 ? 10%. O experimento foi realizado em blocos ao acaso, variando de cinco a oito tratamentos e com três e cinco repetições cada tratamento, com 10 insetos por repetição. Os dados obtidos foram submetidos à análise de variância e as médias foram comparadas pelo teste de Tukey (p<0,05). Pelos resultados obtidos conclui-se que as doses letais e esterilizantes para todas as fases do ciclo evolutivo do E. aurantinana, foram: ovos a dose letal foi 100Gy a esterilizante 50 Gy; larva de segundo instar a dose letal foi150 Gy a esterilizante 100 Gy; larva de ultimo instar a dose letal foi de 200 Gy a esterilizante 150 Gy; pupa a dose letal foi de 400 Gy, a esterilizante de 300 Gy; já para adultos a dose esterilizante também foi de 300 Gy. Portanto uma dose de 400 Gy pode ser utilizada para o tratamento quarentenário de todas as fases do ciclo evolutivo do bicho-furão-dos-citros / The objective was to determine the lethal and sterilizing doses of gamma radiation for all phases of the life cycle of Ecdytolopha aurantiana (Lima, 1927) (Lepidoptera: Tortricidae) borer of the citrus, aiming its control. The work was conducted in Radiobiology Laboratory and Environment / Radioentomology of the Center for Nuclear Energy in Agriculture (CENA) in Piracicaba city, University of São Paulo (USP). For irradiation of all insect stages was used a source of cobalt-60, type Gammabeam - 650 doses were used: 0 (control), 50, 100, 200, 300, 400 and 500 Gy was irradiated in a dose rate of 1,112 kGy/hour. The assays were performed in a climatic chamber with 25 ? 2?C temperature and humidity on 70 ? 10%. The experiment was conducted in randomized blocks, ranging from five and eight treatments and three and five replicates per treatments, with 10 insects per repetition. The data were submitted to analysis of variance and means were compared by Tukey test (p <0.05). From the results obtained it is concluded that the lethal doses and for sterilizing all stages of the life cycle of E. aurantinana were: egg lethal dose was 100 Gy and 50 Gy the sterilizing; second instar larvae lethal dose was 150 Gy and 100 Gy the sterilizing; last instar larvae of the lethal dose was 200 Gy and 150 Gy the sterilizing; pupae lethal dose was 400 Gy and 300 Gy the sterilizing; the sterilizing dose for adults it was also 300 Gy. Therefore a dose of 400 Gy can be used for quarantine treatment of all stages of the life cycle of the borer of the citrus
37

Tuberculose em primatas não humanos mantidos em cativeiro: uma revisão / Tuberculosis in nonhuman primates in captivity: a review

Valvassoura, Tatiana Almeida 06 February 2012 (has links)
A Tuberculose vem acometendo animais selvagens desde o surgimento das primeiras coleções organizadas. Particularmente, macacos são altamente suscetíveis as micobactérias, gerando grandes perdas econômicas para as instituições, além do risco de transmissão para o homem e animais. As principais micobatérias, que causam a doença em primatas em cativeiro, são o Mycobacterium tuberculosis e Mycobacterium bovis. Acredita-se que primatas do &quot;novo mundo&quot; são menos suscetíveis do que os do &quot;velho mundo&quot;, entretanto observa-se que tuberculose tem sido documentada em várias espécies. A principal forma de transmissão é através de aerossóis contendo os bacilos. A doença pode evoluir para a forma ativa ou latente, dependendo do estado imunológico do animal. Os sinais clínicos podem ser insidiosos, com somente uma alteração comportamental, seguido por anorexia e letargia, alterações respiratórias ou simplesmente o animal pode aparecer morto no recinto. O diagnóstico clínico é difícil e problemático, sendo que muitas vezes as lesões consistentes com a doença só são observadas na necropsia. Por isso o uso de outras ferramentas de diagnóstico é importante, como o teste de tuberculinização, cultivo e isolamento bacteriano, que são os mais usados na rotina das instituições, e os exames radiográficos do tórax e abdômen, testes moleculares e sorológicos. Toda instituição que mantém primatas em cativeiro deveriam possuir programas de prevenção para evitar a entrada da micobactéria dentro da coleção, principalmente ao se adquirir novos animais. Por isso, o emprego de medidas de biossegurança é essencial para diminuir o risco de doenças para o homem e para os animais dentro das instituições. Essas medidas consistem na implantação de uma série de procedimentos e normas operacionais rígidas, como programas de quarentena, programas de saúde para os funcionários e formação de equipe capacitada e treinada. / Tuberculosis has been affecting wild animals since the arising of the first organized collections. Specially, monkeys are highly susceptible to mycobacteria, which cause great economic losses in the institutions, beyond the risk of transmission to man and animals. The main species of mycobacteria, that cause disease in nonhuman primates in captivity, are Mycobacerium tuberculosis and Mycobacterium bovis. It is believed that nonhuman primates from the &quot;new world&quot; are less susceptible than the &quot;old world&quot; ones, however it is noted that tuberculosis has been continually documented in several species. Aerosols that contain infectious bacilli are the main transmission mode. The disease can progress to active or latent form, which depends on the animal&#39;s immune status. The clinical signs can be insidious, with only a behavior change, followed by anorexia and lethargy, respiratory alteration or the animal can appear dead in the room. The clinical diagnostic is difficult and problematic, and often lesions are only observed at necropsy. Therefore, the use of other diagnostic tools is important, as the tuberculin skin test, bacterial culture and isolation, that are most used during the routine of institutions, and radiography of the chest and abdomen, molecular and serological tests. Every institution that maintains nonhuman primates in captivity should have prevention programs to avoid the entry of mycobacteria inside of collection, mainly when new animals are acquired. Thus, the use of biosecurity measures is essential to reduce the risk of disease in humans and animals within institutions. These measures consist in implanting series of rigid procedures and operational standards, like quarantine programs, health programs for employees and formation of the qualified team.
38

Eficiência do processo de beneficiamento de laranja doce na redução de incidência de frutos com mancha preta dos citros (Phyllosticta citricarpa) em packinghouse com frutos destinados ao mercado interno / Efficiency of processing sweet orange on the reduction of incidence of fruits with citrus black spot (Phyllosticta citricarpa) in a packinghouse with fruits allocated for the domestic market

Panosso, Paula Schiavolin 17 April 2014 (has links)
A mancha preta dos citros (MPC) é causada pelo fungo Phyllosticta citricarpa e está entre as principais doenças citrícolas do Brasil. Esse fungo provoca lesões superficiais e queda precoce dos frutos. Essas lesões não comprometem a qualidade interna do fruto, porém limita a comercialização no mercado brasileiro de frutos e impede que o Brasil seja exportador do produto in-natura devido à presença dos sintomas. A MPC é uma doença quarentenária A1 na União Europeia (UE) por não estar presente em seus países membros. Essa é a principal razão pela qual o Brasil, embora seja o maior produtor mundial de frutos e suco, não apareça no topo dos países exportadores. O principal controle utilizado para a doença é o controle químico associado a práticas culturais. Os principais fungicidas utilizados são os cúpricos, os benzimidazóis e a mistura de estrobilurinas e triazóis. Porém, em 2012 os benzimidazóis foram retirados da lista de produtos permitidos em pomares com frutos destinados ao mercado externo. Nesse contexto, os produtores se veem com uma opção a menos para o controle da doença no campo. Sabe-se que o beneficiamento em packinghouse é um método de controle dos frutos em pós-colheita, porém a eficiência desse processo nunca foi avaliada. Por essa razão, este trabalho teve por objetivo avaliar a eficiência do processo de beneficiamento em packinghouse na redução de incidência de frutos com MPC. Para isso, foi avaliado quinzenalmente, no período de abril de 2012 a maio de 2013 a incidência e a severidade de MPC nos frutos antes a após o beneficiamento pelo packinghouse. Para a avaliação da severidade foi utilizada a escala diagramática. A redução da incidência no lote chegou a 53,3 %, enquanto que a redução da severidade no lote chegou a 68 %. Foi observado que grande parte dos frutos se agrupa em intervalos baixos de severidade, entre 0,5 a 1,7 %. A eficiência do packinghouse aumenta com o incremento na classe de severidade, por exemplo, a redução da MPC é de 100 % em casos em que a severidade dos frutos é maior que 11,6 %. Os frutos com baixa severidade são dificilmente detectados e não são retirados da linha de beneficiamento, já que o packinghouse tem seus frutos destinados ao mercado interno e menos exigentes na questão fitossanitária. A quantificação de picnídios em lesões novas de mancha sardenta foi realizada em frutos que já apresentavam sintomas da doença. Os frutos foram mantidos em recipientes plásticos, a temperatura de 25 ? C sob luz constante, o acompanhamento era feito a cada dois dias. Foi verificado que o aparecimento de picnídios ocorre de 2 a 18 dias após o aparecimento da lesão e não foi verificado um padrão de produção dos picnídios em manchas sardentas. O efeito da aplicação de cera de carnaúba e fungicida imazalil nos sintomas pós-colheita foi realizado em frutos com três tratamentos, (1) cera de carnaúba, (2) cera de carnaúba + imazalil e (3) controle. Os frutos foram mantidos em recipientes plásticos, a temperatura de 25 ? C sob luz constante, a avaliação era feita a cada quatro dias. Foi verificado que a taxa de progresso da doença foi crescente para os tratamentos (1) cera de carnaúba + imazalil, (2) cera de carnaúba e (3) controle. As taxas diferiram estatisticamente pelo teste-t a 5 % de probabilidade. / The citrus black spot (CBS) is caused by Phyllosticta citricarpa fungus and is one of the main citrus diseases in Brazil. This fungus causes surface lesions and early fruit drop. These lesions do not compromise the internal quality of the fruit; however, they limit its commercialization in the domestic market and hinder exports of the fruit in-natura. The CBS is a quarantine disease classified as A1 by the European Union (EU) with no occurrence in its member countries. For this reason, the EU has tolerance zero for fruits contaminated with CBS. This is the main reason that stops Brazil, the world\"s largest fruit and juice producer, from being the top citrus exporter country. The disease is controlled mainly by the use of chemicals associated with cultural practices. The main chemical products used are cupric, benzimidazols and mixture of strobilurin and triazole. However, in 2012 benzimidazols were banned from the domestic market. Therefore, producers have fewer options for the control of the disease in the field. The processing of fruits at a packinghouse is a method of post-harvest fruit control; nevertheless, the efficiency of this process was never assessed. This study aimed to evaluate the efficiency of packinghouse process in reducing incidence of CBS in oranges. The incidence and severity of CBS in the fruits before and after packinghouse process were evaluated every fifteen days, from April 2012 to May 2013. The diagrammatic scale was used to assess the severity of CBS. Incidence reduction of these fruits can reach 50.5 %, whereas the reduction of fruits severity decreased up to 68 %. We observed that large quantities of fruits are aggregated to low severity breaks on the diagrammatic scale, from 0.5 to 1.7 %. For fruits with high severity, the detection is easier and they are removed from the processing belt, improving efficiency. The efficiency of a packinghouse in reducing the occurrence of CBS is 100% in cases where severity of fruits is greater than 11.6%. The behavior adopted by the packinghouse to detect fruits changes depending on severity. The fruits with low severity are hard to be detected on the belt and are not removed from the processing line, because the packinghouse studied allocates its fruits to the domestic market, which is less demanding in terms of plant health. Quantification of pycnidia in new freckled spot lesions was carried out in fruits that already show symptoms of the disease, the fruits were kept in containers at 25 ? C under constant light, the monitoring was done every two days. It was found that the appearance of pycnidia was between 2 and 18 days after onset of the injury and was not observed standard in pycnidia production. The appearance of freckles spot was performed with three treatments on fruit (1) carnauba wax, (2) carnauba wax + imazalil and (3) control. The fruits were kept in containers at a temperature of 25 ? C under constant light, the assessment was carried out every four days. It was found that the rate of progress of the disease increased for treatment (1) Carnauba wax + imazalil, (2) carnauba wax and (3) control. Rates differed statistically in the t-test at 5% probability.
39

Irradiation as an alternative phytosanitary treatment for Arhopalus ferus and Hylurgus ligniperda

van Haandel, Andre January 2014 (has links)
Wood products all require treatment to mitigate phytosanitary risk prior to exportation. The most common phytosanitary treatment applied to Pinus radiata logs is Methyl Bromide (MeBr). The Environmental Protection Agency (EPA) in 2010 stated that MeBr must not be release into the atmosphere past 2020. This poses a problem for New Zealand log exports. Radiation has been identified as a possible alternative phytosanitary treatment for export wood products. This study aimed to quantify the effective dose of radiation necessary to sterilise two forest pest species; Arhopalus ferus and Hylurgus ligniperda. These species are representative of two different types of forestry pests; bark beetles (H. ligniperda) and wood borers (A. ferus). All applicable life stages for both species were tested. Arhopalus ferus adults were the most susceptible life stage identified with an LD99 of 30.2Gy ± 13.5 Gy (95% confidence interval). Arhopalus ferus eggs were less susceptible with a LD99 of 750Gy ± 776Gy observed; however there is low confidence in this result due to a methodological issue in one treatment replicate. Hylurgus ligniperda eggs were observed to be less susceptible than A. ferus eggs with a LD99 of 289Gy ± 92Gy. Results for the other life stages were inconclusive due to poor control survival, however the information gained was used to develop improved methods for further experimentation, which is on-going and showing positive results so far. The results of this experiment have indicated that radiation can be an effective method of sterilising forestry pests. To date radiation has not been used as phytosanitary risk mitigation for wood exports; however it is widely used for risk mitigation in agricultural products. Currently there remains a large amount of unknown information regarding, the effectiveness for irradiation of logs, the effective dose require for sterilisation of the most tolerant forestry pest and public acceptability of irradiation as a phytosanitary treatment. These knowledge gaps and an economic assessment must be completed before irradiation can be used as a phytosanitary risk mitigation technique for forestry products.
40

Non-pharmaceutical Intervention Strategies for Pandemic Influenza Outbreaks

Martinez, Dayna Lee 01 January 2012 (has links)
In case of a pandemic influenza outbreak, non-pharmaceutical interventions will likely be the only containment measure at the early stages of the pandemic when vaccines are not available. NPIs also oer an option for decreasing the probability of creating antiviral resistant viruses product of a mass prophylaxis campaign. In countries where there are not enough resources for vaccines and antivirals, NPIs may be the only mitigation actions available. NPIs have been increasingly used in preparedness plans. We can see recommendations and guidelines regarding the use of NPIs in countries, health departments and universities. Also, researchers all around the world have study the impact of NPI's in pandemic influenza outbreaks, most of them using simulation as their modeling tool. Our review of the aforementioned plans and literature shows that there is a lack of consensus in how to implement these interventions. They vary widely in the choice of key parameters such as intervention initiation threshold, duration and compliance. We believe that the lack of uniformity in NPI mitigation strategies arise from the uncertainty in the virus epidemiology and the current lack of scientic knowledge about the complex interactions between virus epidemiology with social behavioral factors and mitigation actions. In this dissertation we addressed this problem by modeling pandemic influenza outbreaks using an agent-based simulation approach. The model incorporates detailed popu- lation demographics and dynamics, variety of mixing groups and their contact processes, infection transmission process, and non-pharmaceutical interventions. Using a statistical experimental design approach we examine the influence of characteristic parameters of virus epidemiology, social behavior, and non-pharmaceutical interventions on various measures of pandemic impact such as total number of infections, deaths and contacts. The experimental design approach also yields the knowledge of the extent of interactions among the above parameters. Using this knowledge we develop eective NPI strategies and demonstrate the efficacy of these strategies on large-scale simulated outbreaks involving three dierent scenarios of virus transmissibility. The results show that signicant improvements in the NPI based pandemic mitigation approaches can be attained by the strategies derived from our methodology.

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