For decades scientists believed that herbivory had minimal impact on freshwater ecosystems. We now know that herbivory in freshwater systems equals or exceeds herbivory in terrestrial and marine systems. In extreme cases, herbivores can change clear, macrophyte dominated ecosystems into turbid plankton dominated ecosystems. Even though research on plant-herbivore interactions in freshwater systems has increased, there is still much that is unknown. This thesis is comprised of four studies investigating freshwater plant-herbivore interactions across multiple spatial scales. The first study investigated how induced chemical defenses in Cabomba caroliniana suppress herbivore consumption and growth as well as how this herbivore-generated change in plant chemistry affects the growth of plant associated microbes. At the spatial scale of individual ponds or lakes, consumers that induce their host plants may also be indirectly affecting other consumers and microbial pathogens via changes in this shared resource. The second study moves to an ecosystem scale and investigates how exotic versus native apple snails may impact Everglades' habitats. We investigated plant preference, consumption, growth and conversion efficiencies in the singly native apple snail to occur in the U.S. (Pomacea paludosa) versus four introduced species (P. canaliculata, P. insularum, P. haustrum and P. diffusa). We found that even though plant preferences are similar, invasive snails tend to eat more, grow more rapidly, and sometimes more efficiently than natives. This suggests that invasive species could have a large impact on the environment, especially the abundance of submerged plants. The third study investigated how palatability of freshwater plants varies with latitude (i.e. geographic scale). Increased herbivory at lower latitudes is hypothesized to select for increased plant defenses, which has been shown to be true for tropical forests, salt marshes, and seaweeds. When we contrasted eight confamilial plants collected in Indiana versus Southern Florida, three of four herbivores significantly preferred northern plants. When we evaluated a second set of plants collected from Indiana versus Central Florida, only one of three herbivores preferred the northern plants. Overall, our results suggest a preference for northern plants, but the strength of this relationship was variable. We hypothesize that this variability may be driven by 1) local variance in herbivore pressure that creates variance in plant defenses, and/or 2) the effect of winter length on the survival and feeding rate of herbivores. The final study expanded to a world scale, and investigated herbivore preference for native vs exotic plants. We found that both N. American crayfish and S. American snails preferred exotic plants over confamilial natives, despite responding to different plant characteristics. The single species of apple snail that occurs in N. American showed no preference for native or exotic plants from a N. American perspective, but instead exhibited preferences that correlated with its history of evolution in S. America. As the N. American species is a sister species of the S. American snails, feeding by the N. American snail appears more affected by its S. American lineage than its recent history in N. America. This suggests that phylogenetic legacy will affect choices of the herbivore as well as resistance or susceptibility of plants.

Submitted by Anderson Silva (avargas@icict.fiocruz.br) on 2012-05-09T12:47:47Z No. of bitstreams: 1 zilene_m_pereira_ioc_ebs_0008_2010.pdf: 15520398 bytes, checksum: 493b6f7c7e7dea5020af412b5cc0cffc (MD5) / Made available in DSpace on 2012-05-09T12:47:47Z (GMT). No. of bitstreams: 1 zilene_m_pereira_ioc_ebs_0008_2010.pdf: 15520398 bytes, checksum: 493b6f7c7e7dea5020af412b5cc0cffc (MD5) Previous issue date: 2010 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil. / Achatina fulica, ou caramujo africano, foi introduzido no Brasil em meados da década de 1980 para ser comercializado como “escargot”. No entanto, em virtude da baixa demanda do mercado consumidor, os criadores desativaram seus plantéis, gerando fuga ou liberação intencional de exemplares que, livres no ambiente, espalharam-se rapidamente por quase todo país (24 estados mais o Distrito Federal). As “densas” populações do caramujo africano causam uma série de problemas, como a destruição de hortas e jardins, competição com a fauna nativa, além de poderem transmitir zoonoses como a angiostrongilose abdominal e a meningite eosinofílica. A exemplo do que ocorre em outras partes do país, o Município de Barra do Piraí, Estado do Rio de Janeiro, encontra-se também infestado. Visando contribuir para o enfrentamento dos danos causados por essa espécie, o presente estudo objetivou: pesquisar a helmintofauna de populações de A. fulica em alguns bairros de Barra do Piraí quanto à presença de larvas de helmintos de importância médico-veterinária; analisar as percepções relacionadas ao caramujo africano entre estudantes do Ensino Fundamental de uma escola pública estadual no referido município. A pesquisa, de abordagem qualitativa, foi realizada em duas etapas: 1) coleta de exemplares de A. fulica nos bairros Arthur Cataldi, Dorândia, Química, Boca do Mato e São João no período de fevereiro de 2008 a novembro de 2009, os quais foram analisados no Laboratório de Malacologia do Instituto Oswaldo Cruz/Fiocruz (Referência Nacional em Malacologia Médica); 2) aplicação de 82 questionários e a realização de quatro grupos focais com alunos do Ensino Fundamental, além de observações de campo. Os resultados obtidos ao longo do trabalho “comprovam” que há uma infestação de caramujos africanos no município. A pesquisa da helmitofauna revelou que caramujos provenientes de dois dos cinco bairros analisados, quais sejam, Química e Dorândia, apresentaram o nematódeo Angiostrongylus cantonensis causador da meningite eosinofílica no homem. Além disso, também foram encontrados no município os nematódeos Strongyluris-like e Aelurostrongylus abstrusus que causam doenças em animais. Os dados referentes ao estudo das percepções revelaram que os alunos identificam a presença do caramujo africano no contexto no qual estão inseridos, e embora a maioria acredite que esse animal possa causar doenças, apenas uma minoria afirma conhecer pessoas que tiveram problemas com o caramujo. Os dados igualmente apontam para divergências entre a visão dos alunos e o conhecimento científico sobre as formas de controle de A. fulica e os tipos de agravos, em função do contato ou ingestão dessa espécie. Os laudos referentes ao exame dos moluscos e as recomendações aos órgãos municipais sobre o controle e monitoramento A. fulica já foram encaminhados à secretaria de saúde do município para que sejam tomadas as devidas providências. Da mesma forma o trabalho será disponibilizado aos professores da escola que participou desta pesquisa para que suas contribuições possam auxiliar na prática docente. Espera-se que os resultados deste trabalho possam subsidiar o desenvolvimento de ações de controle e monitoramento de A. fulica no município, bem como ações educativas em contextos formais e não formais de ensino para trabalhar com essa temática, adequadas à realidade da comunidade. / The giant African snail Achatina fulica, was introduced in Brazil in mid-1980 for commercial purposes ("escargot" farming) that were not successful. In spite of marketing efforts the demand was low since Brazilians are not used to eat terrestrial snails. Thus, farmers gave up rearing the snails and unaware of the potential negative consequences released the snails by putting them in the garbage, discarding them on waste land and the edges of highways or throwing them into the rivers. The result was a quick spread throughout most of the country (24 states plus the Federal District). The "dense" populations of A. fulica cause many of problems, such as nuisance and destruction of vegetable gardens and gardens. They may also transmit zoonosis such as abdominal angiostrongylosis and meningoencephalitis. Similarly to other municipalities in the state of Rio de Janeiro, Barra do Piraí is also infested. The present study aimed to investigate the larval helminthes of medical and veterinary importance associated with populations of A. fulica in some districts of that municipality as well as analyze the knowledge and perceptions about that snail among students in a public school. Therefore, methodological procedures were performed in two steps: 1) collecting of specimens of A. fulica from five neighborhoods from February 2008 to November 2009, which were analyzed at the Laboratory of Malacology (Instituto Oswaldo Cruz/Fiocruz), a National Center for Medical Malacology Research; 2) application of 82 questionnaires and conducting four focus groups with elementary school students, and field observations. The search for larval helminthes detected the presence of nematodes of medical-veterinary importance: Strongyluris-like, Aelurostrongylus abstrusus and Angiostrongylus cantonensis larvae (causes eosinophilic meningitis in humans) in the neighborhoods of Química and Dorândia. As for the study of the perceptions the data revealed that students identify the presence of the African snail in the context in which they live. Most of the students believe that the snail can cause disease, but a minority said that knew the health problems related to this animal or even people who had them. The data also point to differences between students' views and scientific knowledge on ways to control A. fulica and the types of injuries, depending on contact or ingestion of this species. The reports concerning the examination of snails and recommendations to the municipal authorities over the control and monitoring A. fulica have been forwarded to the secretary of health of the city for taking appropriate action. Moreover, the work will be available to school teachers who participated in this survey for their contributions to assist in teaching. It is hoped that the results of this study may support the development of control measures and monitoring of A. fulica in the county, as well as educational activities appropriate to the reality of the community.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-03-30T13:50:55Z No. of bitstreams: 1 fabiolaalmeidamatosdesouza.pdf: 1130248 bytes, checksum: af4dc46ef6e65e129aaccbc9a82d075d (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T02:52:30Z (GMT) No. of bitstreams: 1 fabiolaalmeidamatosdesouza.pdf: 1130248 bytes, checksum: af4dc46ef6e65e129aaccbc9a82d075d (MD5) / Made available in DSpace on 2016-04-24T02:52:30Z (GMT). No. of bitstreams: 1 fabiolaalmeidamatosdesouza.pdf: 1130248 bytes, checksum: af4dc46ef6e65e129aaccbc9a82d075d (MD5) Previous issue date: 2013-02-28 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O filo Mollusca é composto por diversas espécies que são amplamente utilizadas pelo ser humano na economia em setores diversos como alimentação e saúde pública. Devido a isto, houve intensa disseminação de espécies exóticas entre diversas regiões do globo, tornando necessário o conhecimento sobre a biologia e o comportamento desses moluscos nas áreas onde foram introduzidos para se prever os possíveis danos à malacofauna e flora nativas. Tais estudos também são relevantes para o desenvolvimento de estratégias de manejo quando o aumento excessivo da população de uma determinada espécie torna-se prejudicial ao ambiente, além de uma possível utilização de moluscos como ferramentas de controle biológico. Rumina decollata (Linnaeus, 1758) é uma espécie oriunda da região Mediterrânea que foi introduzida na América do Norte para o controle biológico de Helix aspersa Müller, 1774 em plantações de frutas cítricas, porém, houve intenso aumento das populações que levou a uma proibição da entrada e criação de R decollata em algumas regiões dos EUA e atualmente, a espécie é encontrada em países da América do Sul como Argentina e Brasil. Não há estudos que descrevam os atos comportamentais nem a biologia da espécie no Brasil, apesar da sua ocorrência em algumas regiões do país. Este estudo foi realizado para esclarecer aspectos biológicos tais como crescimento, reprodução, mortalidade e comportamento de R. decollata em condições de laboratório. Para a realização dos experimentos sobre a biologia da espécie, foram utilizados moluscos criados agrupados (10 moluscos/ grupo) e isolados (30 moluscos/grupo). Para observar o padrão de crescimento os moluscos foram pesados e medidos mensalmente para posterior comparação. Os moluscos foram criados isolados para verificar a ocorrência de autofecundação, e comparar tempo para alcance de maturidade, fecundidade e eclodibilidade dos ovos. Os resultados demonstraram que moluscos agrupados e isolados diferiram quanto ao crescimento entre 0 a 60 dias, com uma maior taxa para os moluscos criados isolados, seguido de uma estabilização, caracterizando um crescimento determinado, padrão que difere do encontrado para outros subulinídeos. O peso diferiu significativamente entre isolados e agrupados, com maiores valores para moluscos agrupados. Não houve mortalidade para os moluscos isolados durante o período de observação. O alcance da maturidade sexual ocorreu a partir de 90 dias para os agrupados e 120 dias para os isolados. Verificou-se a ocorrência de autofecundação, porém, os moluscos realizaram preferencialmente a fecundação cruzada, a qual também foi responsável por um maior número de ovos viáveis. Ficou evidenciado que R. decollata apresentou diferenças em sua biologia quando comparada com os estudos de outros autores em diferentes localidades. Para a descrição do comportamento e interações entre adultos e jovens, foram utilizados 30 moluscos jovens e o mesmo número de adultos observados durante 24 horas através do método scan sample a intervalos de 20 minutos. Os moluscos adultos e jovens apresentaram-se mais ativos durante o período noturno, com somente um ato comportamental (“Interagir”) diferindo significativamente durante as 24 horas de observação, com maior interação entre os adultos. Adultos e jovens diferiram quanto ao ato “Alimentar” e “Deslocar” somente em dois horários e três distintos do período noturno respectivamente. Não houve influência da umidade relativa do ar no comportamento dos moluscos, porém, houve correlação entre a temperatura média e a atividade de adultos e jovens. Tais resultados comprovam que o horário de atividade de R. decollata é semelhante ao descrito para diversos moluscos gastrópodes, inclusive subulinídeos. A diferença entre os atos comportamentais de jovens e adultos demonstra uma possível diferenciação de nichos. / The phylum Mollusca is composed by several species that are largely used in many economic sectors such as food and public health. Because of it, there was a dissemination of alien species among several parts of the world, what make necessary the knowledge of life cycle and behavior in the regions of introduction of these species, in order to predict possible damages to native fauna and flora. These studies are also important to the development of control strategies in case of populations increase, turning a species into a pest, besides, its is useful tin case of using a species as biological control. Rumina decollata (Linnaeus, 1758) is a land snail from Mediterranean area that was introduced in the North of USA to control populations of Helix aspersa Müller, 1774 in citrus sp plantations, however, occurred an overpopulation that lead to a prohibition of R. decollata entrance and rearing in this country and nowadays, the species is found in South America in Argentina and Brazil. There is a lack of studies that describe the behavioral biology and the lifecycle of this species in Brazil, despite its occurrence in some districts of the country. This study was realized in order to clarify biological traits such growth, reproduction and behavior of this species in laboratory conditions. For life cycle assay, snails were created grouped (10 snails/ group) and isolated (30 snails 1/goup). To analyze growth patterns, snails were weighted and measured every month. The isolation was to verify the occurrence of self-fertilization and to compare the time to onset sexual maturity, fecundity and egg hatchability. Results showed that snails grouped and isolated differed in growth between 0 and 60 days, with high rate to isolated snails. There was stabilization that characterize determinate growth pattern that differ from other subulinids. Weight was significantly different, with higher rates to grouped snails. It was not observed mortality in isolated snails during the observation period. The reaching of maturity occurred from 90 days for grouped snails and from 120 days to isolate. It was verified selffertilization, although the cross fertilization seems to be the pattern what can be confirmed by the higher number of viable eggs. It was evidenced that R. decollata showed differences in its biology when compared to studies realized in other regions. To describe behavior of juvenile and adult individuals, it was used 30 snails of each age, observed for 24 hours by the scan samplé method. Adult and juvenile were more active during nocturnal period, with only one act (“Interact”) significantly different during the 24 hours, with more interaction between adults. Adult and juvenile showed difference in the acts “Feed” and “Dislocate” in two and three different hours in nocturnal period respectively. It was not observed influence of relative air humidity, but there was a correlation between mean temperature and the activity of adult and juvenile snails. Such results demonstrate that the activity period of R. decollata is alike to other terrestrial snails, including subulinids. The difference between behavioral displays of juvenile and adults indicate the occurrence of niche differentiation.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-30T15:35:43Z No. of bitstreams: 1 brunaaparecidadesouza.pdf: 2457820 bytes, checksum: fda7842f711a83f2ffb69aab8ce0f319 (MD5) / Rejected by Adriana Oliveira (adriana.oliveira@ufjf.edu.br), reason: Primeira letra de cada palavra chave em maiúsculo on 2016-07-02T12:25:57Z (GMT) / Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-04T10:32:31Z No. of bitstreams: 1 brunaaparecidadesouza.pdf: 2457820 bytes, checksum: fda7842f711a83f2ffb69aab8ce0f319 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-13T16:17:32Z (GMT) No. of bitstreams: 1 brunaaparecidadesouza.pdf: 2457820 bytes, checksum: fda7842f711a83f2ffb69aab8ce0f319 (MD5) / Made available in DSpace on 2016-07-13T16:17:32Z (GMT). No. of bitstreams: 1 brunaaparecidadesouza.pdf: 2457820 bytes, checksum: fda7842f711a83f2ffb69aab8ce0f319 (MD5) Previous issue date: 2012-02-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O molusco terrestre Subulina octona (Bruguière, 1789) atua como hospedeiro intermediário de helmintos parasitos de humanos e animais domésticos. Em alta densidade populacional também pode atuar como praga agrícola, o que levanta a necessidade de medidas de controle. A busca por moluscicidas de origem vegetal tem se intensificado nos últimos anos devido às vantagens que as espécies vegetais apresentam. Os vegetais Bidens pilosa Linné e Mikania glomerata Sprengel apresentam ampla distribuição geográfica, são frequentemente utilizados na medicina popular e apresentam princípios ativos solúveis em água e com reconhecida atividade moluscicida. Objetivou-se com esse trabalho comprovar a presença desses princípios ativos, calcular as concentrações de referência (CL50 e CL90) sobre adultos de S. octona e avaliar os efeitos das CL50 obtidas sobre aspectos biológicos e comportamentais desse molusco em diferentes fases de desenvolvimento. Para a obtenção das CL50 e CL90 foram utilizadas cinco concentrações do extrato aquoso das espécies vegetais, no qual 30 moluscos (10moluscos/grupo) foram utilizados para cada concentração e para o controle. Os grupos tratados foram expostos à 5mL dos extratos por contato direto com a solução por 24 horas seguidas de 24 horas de recuperação e grupos controle foram expostos a água destilada pelo mesmo período. As concentrações de referência foram obtidas pela análise Probito utilizando o software BioStat 2008, versão 2.5 . As CL50 obtidas foram testadas sobre ovos, jovens recém-eclodidos e jovens de 30 dias e adultos que ficaram expostos aos tratamentos por 24 e 48 horas. Grupos controle ficaram expostos pelo mesmo período em água destilada. Para os adultos foram realizadas três aplicações das CL50 em intervalos de 30 dias. As observações para a análise de repelência em adultos foram realizadas nos primeiros 10 minutos após a primeira aplicação. A eclosão, sobrevivência e reprodução foram avaliadas e os dados comparados pelo teste de Kruskal-Wallis (p<0,05) utilizando o software BioEstat versão 5.0. A análise fitoquímica comprovou a presença de flavonóides, taninos e saponinas nos extratos aquosos dos dois vegetais. As CL50 e CL90 obtida para B. pilosa foi de 51,4mg/mL e 74,1mg/mL respectivamente, e para M. glomerata foi de 44,6mg/mL para CL50 e 71,9mg/mL para CL90. A atividade repelente dos extratos foi verificada logo após a aplicação. A sobrevivência dos adultos foi significativamente reduzida após a segunda aplicação dos extratos. Da mesma forma, a fecundidade diminuiu para os grupos expostos por 24 horas. Não foi verificado diferença significativa na eclosão de moluscos da prole provenientes dos adultos expostos aos tratamentos. Todavia, a eclosão dos moluscos provenientes de ovos expostos diretamente aos extratos aquosos das plantas testadas, foi, em média, significativamente reduzida. O tempo de exposição também influenciou, onde os grupos expostos pelo maior tempo tiveram sua eclosão reduzida. Os extratos também influenciaram na sobrevivência dos eclodidos proveniente dos ovos tratados e dos jovens-recém-eclodidos e dos de 30 dias. Alterações sobre o crescimento foi verificado para os tratamentos. Os resultados observados nesse estudo provavelmente foram provocados pela mistura complexa de princípios ativos que podem interagir de forma sinérgica, aditiva ou até facilitando a absorção de algum composto. A facilidade na obtenção, preparação e aplicação desses extratos tornam esses vegetais possíveis candidatos para programas de controle desse molusco. / The land snail Subulina octona (Bruguière, 1789) is an intermediate host of helmints that parasitizes humans and domestic animals. In high densities it can also be a crop pest making necessary the application of control measures. The search for plant molluscicide increased in last years due to its advantages. The plants Bidens pilosa Linné and Mikania glomerata Sprengel are widely distributed and are frequently used in folk medicine. They have active principles that are water soluble and with proven action against snails. The aim of this study was to confirm the presence of these active principles, to calculate the reference concentrations (LC50 e LC90) in adult S. octona and to evaluate the effects of the LC50 obtained on biological and behavioral aspects of this snail in different development phases. To obtain the LC50 e LC90 five concentrations were utilized for each plant aqueous extract, and 30 snails (10snails/group) were utilized for each concentration and for control group. The groups were exposed to 5mL of the extracts by direct contact with the solution for 24 hours followed by 24 hours of recovery period and the control groups were exposed to distilled water for the same time period. The reference concentrations were obtained using the Probit analysis through (BioStat 2008 software, version 2.5). The LC50 obtained were tested on eggs, newly hatched, 30 day old individuals and adults that were exposed to the treatments for 24 and 48 hours period. Control groups were exposed to distilled water. For the adults, were utilized three applications of the LC50 every 30 days. The observations to analyse the repellency in adults were made at the realized at the 10 first minutes after the first application. The hatchability, survival and reproduction were evaluated and the data were compared by using the Kruskal-Wallis (p<0,05) (BioEstat software, version 5.0). The phytochemical analysis confirmed the presence of flavonoids, tannins and saponins in the aqueous extracts of both plants. The LC50 and LC90 obtained for B. pilosa was 51.4mg/mL and 74.1mg/mL respectively, and for M. glomerata was 44.6mg/mL for LC50 and 71.9mg/mL for LC90. The repellency of the extracts was verified after the application. The survival of adult snails was signficantly diminished after the second application of the extracts. In the same way, the fecundity was reduced in groups exposed for 24 hours. It was not verified significantly difference in offspring hatchability from adult snails exposed to the treatment. However, the eggs exposed directly to the treatments had significantly reduction in hatchability means. The mean hatchability of the snail from eggs directly exposed to the treatments were significantly reduced. The extracts also influenced the survival of snails hatched from treated eggs, in newly hatched and 30 day old individuals. Alterations on growth were verified in all treatments. The results obtained in this study were probably due to the complex combination of the active principles that can interact synergistically, aditive or antagonist or even facilitating absorption of some compounds. The facility in the plant collection, extract preparation and application of these extracts turn these plants candidates in the control of this species.

Forecasting the potential range of invasive species is a critical component for risk assessment, monitoring, and management. However, many of these invasive species are not yet at equilibrium which can be problematic for many modelling approaches. Using the climate matching method, MaxEnt, a series of species distribution models (SDMs) and risk analysis maps were created for select apple snail species in Florida: Pomacea canaliculata, P. diffusa, and P. maculata. Apple snails, freshwater gastropods in the family Ampullariidae, are native to South America and were introduced to the United States via the pet trade approximately 40 years ago. These highly invasive species have already been introduced in ten states and established in at least seven. The models and risk analysis in this study show the majority of Florida was at least moderately suitable for all apple snails modeled, with P. maculata posing the greatest threat.

Canals surrounding the Everglades carry enriched and polluted water high in minerals and nutrients. These enriched waters impact adjacent marsh habitats, altering flora and fauna species and abundance. Multiple studies have found gradients in nutrient levels as a function of distance from canals and emphasize the sensitivity of some organisms to these changes in water chemistry. Florida apple snails, Pomacea paludosa Say, are just one of many Everglades species sensitive to changes in water chemistry. They serve as an important staple in the diets of many Everglades predators including turtles, crayfish, limpkins and most importantly the endangered snail kite, Rostrahamus sociabilis which feeds almost exclusively on the apple snail. To examine potential effects of water chemistry on apple snail breeding patterns, we observed snail egg size, egg number per clutch, and carbon and nitrogen contents along water chemistry gradients and among snail breeding months at the Arthur R. Marshall Loxahatchee National Wildlife Refuge. Egg number per clutch and egg diameters were greatest in the most impacted zones and lowest in the pristine, interior zone. Carbon contents of eggs were highest in the interior and east side of the Refuge and lowest in the west side. Nitrogen contents of eggs were highest in the interior and west side of the Refuge, and lowest in the east side. Significant, albeit weak, positive trends were found between N content and egg diameter, C content and egg diameter, and between egg number per clutch and egg diameter, but only among specific zones and months. Results from this study suggest that snails in areas of the Refuge that are influenced by canal-water may produce greater numbers of apple snail offspring with greater egg diameters than those in less impacted areas. However, we do not know if this translates into higher hatchling success and survival.

The digenetic trematode, Bolbophorus damnificus, poses a substantial threat to catfish aquaculture, causing significant economic losses. Infestations lead to suppressed feed consumption, secondary bacterial infections and poor production performance. Survey data reveals widespread infestation in the in the southeastern United States. Current control strategies involve the application of a concentrated copper sulfate solution to reduce snail populations which serve as the first intermediate host of the trematode life cycle. This study aimed to improve treatment efficacy by developing a granular copper sulfate application system. A modified Gandy fertilizer applicator, equipped with a programmable control system, demonstrated accurate distribution of copper sulfate crystals along pond margins at various speeds. Granular copper sulfate was effective in killing snails along the pond margins at treatment rates between 1-3 ppm. The innovative system offers a practical, single-pass solution to combat trematode infestations in catfish ponds and minimizes logistical challenges associated with multiple applications.

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The frequent cause of failure of prostate carcinoma radiotherapy and chemotherapy is the emergence of resistance and a progress into the essentially incurable metastatic form of disease. Although the mechanisms of the radioresistance and chemoresistance are still not well understood, recent studies indicate that transcription factor Snail, a key mediator of the epithelial-mesenchymal transition and subsequent metastasis formation, plays a critical role in the development of the chemoresistance and radioresistance in the tumor cells. As the activation of the optimal DNA damage response pathway is the determining factor for the cell survival after chemotherapy and radiotherapy, we hypothesized the role of Snail in the transcription regulation of these processes. In this study, we first analyzed the relationship between Snail and ATM kinase, as the ATM was recently reported to regulate stability of Snail by its phosphorylation. Although, we observed a modest effect of ATM inhibition on Snail levels after cancer cells exposure to ionizing radiation, we did not fully reproduced the recently published findings. Furthermore, we evaluated the role of Snail in transcription regulation of cyclin-dependent kinase inhibitor p21waf1/cip1 . Our data point towards the suppressive role of Snail in p21waf1/cip1...

For a PV plant it is of fundamental importance that the operation of the PV modules is free from faults or at least that the faults can be detected early, to ensure efficient electricity production. Some defects such as cracks can be seen in visible light while microcracks and damage to the silicon material can only be seen through special lighting. This study focuses on the most common defects in photovoltaic (PV) systems. Compare the infrared (IR) technology with the new ultraviolet (UV) fluorescence image technique for PV characterization, based on their accuracy and uncertainty factors under an experimental field investigation. In this study, first a literature study was conducted to the most common defects in PV system and their impact on electricity generation. Then a simulation model of a PV system was created in PVsyst and exported to Microsoft Excel which was used to evaluate how different defects at different stages of the PV cell's life cycle impact electricity generation, performance parameters and economic exchange. Furthermore, experiments with UV and IR was implemented at a PV system located in Dalarna and some PV modules at MDH. It was conducted that occurrence of snail tracks, delamination and hot spots in combination with bypass failures and non-functioning cell will affect the economic profitability in the long run and the payback time will increase since their impacts on electricity generation and performance parameters are huge. The worst case is when PV modules are affected by the fault in bypass diode and non-functioning cell which result to a payback time longer than the module's lifetime and huge amount electricity losses in different bypass diodes configurations. Since UV and IR are two different methods that are performed in two different ways, different errors occurred during the measurements. The biggest external factor was the weather that determined if the experiment could be implemented. The IR method gave decent results and was quicker to use, but the UV method highlighted some defect which could not be seen with the IR technology.