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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.
271

Ett Färgat Köpbeteende : En studie om färgers påverkan på konsumenters uppfattning av märkning / A Colorful Consumer Behavior

Myhrman, Martin, Uppman, Robin January 2015 (has links)
Titel: Ett Färgat Köpbeteende Nivå: C-uppsats i ämnet företagsekonomi Författare: Martin Myhrman & Robin Uppman Handledare: Jonas KågströmDatum: 2015 - 05 Syfte: Bakgrunden till att vi har utfört denna studie är att forskning om färgers påverkan på beslutsfattande inom ämnet marknadsföring är begränsad, tidigare forskning har även pekat på att vidare forskning borde beröra vilka faktorer som skulle kunna påverka konsumenters uppfattning om genmodifierade produkter. Således är vårt syfte:“Syftet med denna uppsats är att undersöka hur färgkodad märkning kan kompensera för den negativa uppfattningen som kan råda kring genmodifierade livsmedel.” Metod: För att besvara vårt syfte har vi valt att utföra ett experiment. Studien genomfördes på 120 respondenter på en högskola i Sverige, testpersonerna utförde ett smaktest där de tre olika betingelserna var märkta med olika färger (röd, blå och grön). Den data vi fick in analyserades sedan med hjälp av statistikprogrammet IBM SPSS Statistics 22, därefter har vi tolkat och diskuterat resultaten. Resultat & Slutsats: Vårt huvudsakliga fynd är att röd färg på negativ märkning genererar lägre betalningsvilja än grön och blå färg, vårt resultat korroborerar tidigare forskning som bland annat menar att röd färg bidrar till en aggressivare sinnesstämning och ett mer analytiskt tänkande. I övrigt har vi sett tendenser till att färgen på märkningen inte påverkat varken smakupplevelsen eller hälsouppfattning. Förslag till vidare forskning: Flertalet av våra resultat har inte uppnått statistisk signifikans, vilket troligtvis beror på att vårt urval har varit för litet, vidare forskning borde replikera vår studie på ett större urval. Utöver detta förslag till framtida forskning anser vi att följande bör undersökas:- Hur påverkar färgmärkning uppfattningen om andra GMO-produkter?- Hur blir köpbeteendet påverkat av olika färgnyanser?- Hur förhåller sig varumärke och färg till varandra i köpbeslut? Uppsatsens bidrag: Vår studie har bidragit till att branschen bör tänka på att använda färger med viss försiktighet när det kommer till märkning. Vidare har vi visat att färger påverkar kunders betalningsvilja, vilket är vårt bidrag till ämnet marknadsföring. / Title: A Colorful Consumer Behavior Level: Final assignment for Bachelor Degree in Business Administration Author: Martin Myhrman & Robin Uppman Supervisor: Jonas KågströmDate: 2015 – 05 Aim: The background of our study was grounded in the fact that the research of colors impact are limited in the field of marketing. Studies have also shown that future research should examine which factors that affect consumer’s perception of genetically modified products. The aim of our study is as follows: “The aim of this study is to examine how colored labeling might compensate for the negative perception of genetically modified products.” Method: In this study we have performed an experiment. The experiment took place at a University in Sweden and we had 120 respondent commits. The respondents were asked to perform a taste test in which the color of a label was manipulated between three test groups (red, blue and green). The collected data was analyzed with IBM SPSS Statistics 22, further the results were interpreted and discussed. Result & Conclusions: Our main finding is that the color red on a negative label generated a lower willingness to pay than both blue and green. This result confirms previous research which among other things says that the color red trigger an aggressive mindset and encourage analytical thinking. Furthermore we have seen trends that indicate that colors do not affect the taste and health perception. Suggestions for future research: Many of our results have not been statistically significant, which probably depends on our relatively limited sample, further research should replicate our study with a wider sample. In addition to this suggestion we would like to see further research concerning:- Colors impact on the perception of other GMO products.- The impact of color shades on consumer behavior.- The relation between brands and colors in buying decisions. Contribution of the thesis: Our contribution to people working with marketing is that they should be aware that colored labels may affect the consumer perception. Furthermore we have shown that colors affect consumer’s willingness to pay, which is our contribution to the field of marketing.
272

Autenticação de óleos comestíveis empregando espectroscopia UV-Vis e quimiometria

Alves, Francieli Cassia Gomes Barroso Simão 17 December 2015 (has links)
Com a busca pela praticidade e rapidez na obtenção dos resultados, torna-se cada vez mais importante a implementação de métodos que possam ponderar se os resultados quantitativos são realmente necessários. Os métodos qualitativos são utilizados como uma triagem que antecedem a quantificação e que permite uma redução tanto de tempo como de custos. Estes métodos têm cada vez mais ganhado importância e o uso instrumental proporcionou novas perspectivas e garantia de uma maior confiabilidade e aplicabilidade. O desenvolvimento de metodologias qualitativas aliando métodos instrumentais e quimiometria podem ser apropriados para autenticação de amostras. Desta forma, associado à espectroscopia na região do ultravioleta e visível (UV-Vis) o método quimiométrico de reconhecimento de padrões supervisionado de mínimos quadrados parciais com análise discriminante (PLS-DA), mostrou ser uma ferramenta capaz de autenticar amostras de óleo de soja transgênica e não transgênica, bem como, a autenticação de azeite de oliva extra virgem de acordo com os percentuais de acidez. Além disso, o método proposto permite uma análise rápida e não destrutiva da amostra. Nos estudos, a autenticação de óleos de sojas transgênicos e não transgênicos pode ser atribuída ao deslocamento batocrômico, provavelmente devido às diferenças no grupo cromóforo presente nas amostras transgênicas e não transgênicas, enquanto que nos azeites extra virgem de diferentes percentuais de acidez a autenticação pode ser atribuída a ocorrência de efeitos hipercrômico e hipocrômico. A espectroscopia na região do UV-Vis permitiu a autenticação geográfica de azeites de oliva da região do Mediterrâneo através do método quimiométrico de análise de componentes independentes (ICA). Por ser um método baseado na independência estatística, diferenças entre as amostras provenientes de diferentes países banhados pelo mar Mediterrâneo puderam ser discriminadas, bem como amostras provenientes de um mesmo país. / The search for practical and quickly results increase the importance of methodologies that can ponder if the quantitative results are really needed. The qualitative methods are used as a prior screening to quantification and allows a reduction of time and costs. These methods have increasingly its importance and the instrumental employ provided new perspectives and ensuring greater reliability and applicability. The development of qualitative methods combining instrumental and chemometric can be appropriate for authentication samples. Thus, coupled with spectroscopy in the ultraviolet and visible region (UV-Vis) the supervised pattern recognition method of partial least squares with discriminant analysis (PLS-DA), showed be a tool to authenticate transgenic and non-transgenic soybean oil samples, as well, extra virgin olive oil according to the acidity percentage. Furthermore, the proposed method promote a rapid and non-destructive analysis of the samples. Authentication studies of transgenic and non transgenic soybeans oils can be attributed to the bathochromic shift, due to differences in the chromophore group present in the transgenic and non transgenic samples, while in the extra virgin olive oils with different acidity percentages the authentication can be attributed to the occurrence of hyperchromic and hypochromic effects. UV-Vis spectroscopy allowed the geographic authentication of extra virgin olive oils from the Mediterranean region through the chemometric method of independent component analysis (ICA). Due the ICA be a method based on statistical independence, differences between samples from different countries around the Mediterranean Sea were authenticated, as well the samples from the same country.
273

Srovnání GM hybridu kukuřice MON 810 s vybranými hybridy. / Comparison of GM hybrid maize MON 810 with hybrids selected

POSPÍCHAL, Miroslav January 2015 (has links)
The aim of the thesis was to evaluate and to compare the rate of corn borer and the production capability of 4 hybrids of corn (Zeamays L.) of different earliness. For the comparison a variety test was layed out in the land of my father in Klimětice (Central Bohemia). Before the harvest a sampling for detection of dry matter content in the biomass has been made to determinate the date of harvest. The number of samplings depended on the attainment of required dry matter content in the biomass. By the harvest the yield and dry matter content of the biomass, yield and percentage of corn ears, dry matter yield and the starch yield were determined. In the experiments the differences in infestation of corn borer were determined. Further differences in observed parameters were found out, which were dependent on the different utility trends and earliness of the given hybrids. The result was the appreciation of the given hybrids and determining of their suitability for their growing in conditions of my fathers lands.
274

International civil society actors in Genetically Modificied Organisms as a field of struggle: a neo-gramscian study in Brazil and the United Kingdom

Fontoura, Yuna Souza dos Reis da 27 July 2015 (has links)
Submitted by YUNA FONTOURA (yunareis@gmail.com) on 2015-12-18T14:09:58Z No. of bitstreams: 1 Final Thesis Yuna.pdf: 2767793 bytes, checksum: 75dc946b956c5160ac270cb45e4b4eb1 (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2015-12-18T15:27:27Z (GMT) No. of bitstreams: 1 Final Thesis Yuna.pdf: 2767793 bytes, checksum: 75dc946b956c5160ac270cb45e4b4eb1 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-12-21T18:21:43Z (GMT) No. of bitstreams: 1 Final Thesis Yuna.pdf: 2767793 bytes, checksum: 75dc946b956c5160ac270cb45e4b4eb1 (MD5) / Made available in DSpace on 2015-12-21T18:22:01Z (GMT). No. of bitstreams: 1 Final Thesis Yuna.pdf: 2767793 bytes, checksum: 75dc946b956c5160ac270cb45e4b4eb1 (MD5) Previous issue date: 2015-07-27 / Since the international financial and food crisis that started in 2008, strong emphasis has been made on the importance of Genetically Modified Organisms (GMOs) (or 'transgenics') under the claim that they could contribute to increase food productivity at a global level, as the world population is predicted to reach 9.1 billion in the year 2050 and food demand is predicted to increase by as much as 50% by 2030. GMOs are now at the forefront of the debates and struggles of different actors. Within civil society actors, it is possible to observe multiple, and sometime, conflicting roles. The role of international social movements and international NGOs in the GMO field of struggle is increasingly relevant. However, while many of these international civil society actors oppose this type of technological developments (alleging, for instance, environmental, health and even social harms), others have been reportedly cooperating with multinational corporations, retailers, and the biotechnology industry to promote GMOs. In this thesis research, I focus on analysing the role of 'international civil society' in the GMO field of struggle by asking: 'what are the organizing strategies of international civil society actors, such as NGOs and social movements, in GMO governance as a field of struggle?' To do so, I adopt a neo-Gramscian discourse approach based on the studies of Laclau and Mouffe. This theoretical approach affirms that in a particular hegemonic regime there are contingent alliances and forces that overpass the spheres of the state and the economy, while civil society actors can be seen as a 'glue' to the way hegemony functions. Civil society is then the site where hegemony is consented, reproduced, sustained, channelled, but also where counter-hegemonic and emancipatory forces can emerge. Considering the importance of civil society actors in the construction of hegemony, I also discuss some important theories around them. The research combines, on the one hand, 36 in-depth interviews with a range of key civil society actors and scientists representing the GMO field of struggle in Brazil (19) and the UK (17), and, on the other hand, direct observations of two events: Rio+20 in Rio de Janeiro in 2012, and the first March Against Monsanto in London in 2013. A brief overview of the GMO field of struggle, from its beginning and especially focusing in the 1990s when the process of hegemonic formation became clearer, serves as the basis to map who are the main actors in this field, how resource mobilization works, how political opportunities ('historical contingencies') are discovered and exploited, which are the main discourses ('science' and 'sustainability' - articulated by 'biodiversity preservation', 'food security' and 'ecological agriculture') articulated among the actors to construct a collective identity in order to attract new potential allies around 'GMOs' ('nodal point'), and which are the institutions and international regulations within these processes that enable hegemony to emerge in meaningful and durable hegemonic links. This mapping indicates that that the main strategies applied by the international civil society actors are influenced by two central historical contingencies in the GMO field of struggle: 1) First Multi-stakeholder Historical Contingency; and 2) 'Supposed' Hegemony Stability. These two types of historical contingency in the GMO field of struggle encompass deeper hegemonic articulations and, because of that, they induce international civil society actors to rethink the way they articulate and position themselves within the field. Therefore, depending on one of those moments, they will apply one specific strategy of discourse articulation, such as: introducing a new discourse in hegemony articulation to capture the attention of the public and of institutions; endorsing new plural demands; increasing collective visibility; facilitating material articulations; sharing a common enemy identity; or spreading new ideological elements among the actors in the field of struggle.
275

Effects of glyphosate on infant Health indicators

Dias, Mateus Ferraz 26 May 2017 (has links)
Submitted by Mateus Ferraz Dias (mateusdias91@gmail.com) on 2017-06-11T04:22:33Z No. of bitstreams: 1 masters_thesis.pdf: 507645 bytes, checksum: 4af3657d071b94926dc8acc71004616d (MD5) / Approved for entry into archive by Suzinei Teles Garcia Garcia (suzinei.garcia@fgv.br) on 2017-06-12T11:57:08Z (GMT) No. of bitstreams: 1 masters_thesis.pdf: 507645 bytes, checksum: 4af3657d071b94926dc8acc71004616d (MD5) / Made available in DSpace on 2017-06-12T12:52:11Z (GMT). No. of bitstreams: 1 masters_thesis.pdf: 507645 bytes, checksum: 4af3657d071b94926dc8acc71004616d (MD5) Previous issue date: 2017-05-26 / Este trabalho estima o impacto do glifosato sobre indicadores de saúde infantil no Brasil, no período de 2000 a 2009, explorando a adoção da soja transgênica no Brasil e a estrutura hidrográfica do país (ottobacias). Nossos resultados indicam um aumento nas taxas de nascimentos de baixo peso e mortalidade infantil, concentradas em causas de morte associadas aos efeitos esperados do glifosato e em crianças expostas ao glifosato durante o primeiro trimestre de gravidez (período em que o feto é mais suscetível a efeitos negativos sobre seu desenvolvimento). Assim, os resultados sugerem que a regulação do glifosato como herbicida pode ser melhorada levando-se em conta os efeitos negativos sobre a saúde humana, hoje negligenciados. / This work estimates the impact of glyphosate on infant health indicators in Brazil, between 2000 and 2009, exploiting the adoption of genetically engineered soy in Brazil and the country’s hidrographic structure (ottobasins). Our results indicate an increase in low weight birth rate and infant mortality rate, concentrated on death causes associated to glyphosate’s expected effects and on children exposed to glyphosate during the first trimester of pregnancy (when the fetus is more susceptible to negative developmental effects). Hence, the results suggest that regulation regarding use of glyphosate as herbicide can be improved taking into account the nowadays neglected negative effects on human health.
276

Interações da proteína Vip3Aa20, Diatraea saccharalis (Fabricius) e seus parasitóides, Cotesia flavipes (Cameron) e Trichogramma galloi Zucchi

Lohmann, Tiago Rodrigo [UNESP] 11 March 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-11Bitstream added on 2014-06-13T18:26:16Z : No. of bitstreams: 1 lohmann_tr_me_jabo.pdf: 1159043 bytes, checksum: 91192fb7d70eb0a6d02bd04c9badaf8f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente estudo foi avaliar o efeito da proteína Vip3Aa20, originária da bactéria Bacillus thuringiensis Berliner, sobre a broca-do-colmo Diatraea saccharalis (Fabricius) e dois de seus parasitóides: o parasitóide larval Cotesia flavipes (Cameron) e o parasitóide de ovos Trichogramma galloi Zucchi. D. saccharalis mostrou-se suscetível à proteína, apresentando efeitos letais e subletais. Foram afetadas pela proteína as características mortalidade larval, duração do período larval, número de ínstares larvais e peso de larvas, enquanto que a mortalidade pupal e a duração do período pupal não foram afetadas e o peso de pupas apresentou resultados divergentes entre os bioensaios conduzidos. Para os parasitóides, avaliaram-se os efeitos da exposição direta (ingestão da proteína pelos adultos) e indireta (ingestão da proteína por D. saccharalis e posterior parasitismo). Em C. flavipes, não foram observados efeitos pela exposição direta, enquanto que na exposição indireta ocorreu efeito negativo sobre as características peso da massa de casulos e peso do adulto. Estes efeitos podem ser associados ao efeito mediado pelo hospedeiro. Em T. galloi, não foram observados efeitos da proteína Vip3Aa20 sobre os parasitóides, tanto na exposição direta como na indireta / The aim of this study was to evaluate the effect of Vip3Aa20 protein, originating from the Bacillus thuringiensis Berliner bacterium, on sugarcane borer Diatraea saccharalis (Fabricius) and two of its parasitoids: larval parasitoid Cotesia flavipes (Cameron) and egg parasitoid Trichogramma galloi Zucchi. D. saccharalis was susceptible to protein, with lethal and sublethal effects. Larval mortality, larval period, number of instars and larval weight were affected by the protein, while pupal mortality and pupal period were not affected and pupal weight presented discrepant results between bioassays conducted. For the parasitoids, direct (protein ingested by adults) and indirect (protein ingested by sugarcane borer with later parasitism) exposure were evaluated. In C. flavipes, no effects were observed by direct exposure, while in indirect exposure negative effects occurred on the cocoons weight and adult weight. These effects may be associated with the effect mediated by the host. No effects were verified on T. galloi when this species was direct or indirectly exposed to Vip3Aa20 protein
277

Organismos geneticamente modificados na agricultura: histórico, impactos, incertezas e legislação ambiental / Genetically modified organisms and the environment: historical, uncertainties and legislation

Santos, Ana Luiza Marques [UNESP] 27 June 2016 (has links)
Submitted by ANA LUIZA MARQUES DOS SANTOS null (almsrc@yahoo.com.br) on 2016-08-17T16:36:53Z No. of bitstreams: 1 OGMs impressão.pdf: 1737452 bytes, checksum: 4b63e02eaf89d59177e9e14a80bf1e9e (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão com o arquivo completo de seu trabalho em um único arquivo pdf. Agradecemos a compreensão. on 2016-08-18T14:43:07Z (GMT) / Submitted by ANA LUIZA MARQUES DOS SANTOS null (almsrc@yahoo.com.br) on 2016-08-18T16:15:12Z No. of bitstreams: 1 ORGANISMOS GENETICAMENTE MODIFICADOS NA AGRICULTURA HISTÓRICO, IMPACTOS, INCERTEZAS E LEGISLAÇÃO AMBIENTAL.pdf: 3931676 bytes, checksum: 2a6a048b94655516c49a880e09e714fc (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-18T17:18:54Z (GMT) No. of bitstreams: 1 santos_alm_dr_rcla.pdf: 3931676 bytes, checksum: 2a6a048b94655516c49a880e09e714fc (MD5) / Made available in DSpace on 2016-08-18T17:18:54Z (GMT). No. of bitstreams: 1 santos_alm_dr_rcla.pdf: 3931676 bytes, checksum: 2a6a048b94655516c49a880e09e714fc (MD5) Previous issue date: 2016-06-27 / A utilização dos Organismos Geneticamente Modificados (OGMs) na agricultura tem sido alvo da atenção da comunidade internacional, repercutindo sobremaneira nas diferentes áreas do conhecimento humano. Diante das diversas questões decorrentes do uso intensivo destes organismos e dos efeitos causados ao meio ambiente, a presente pesquisa buscou analisar os aspectos históricos, técnicos e sociais relacionados ao tema em questão, observando sobretudo as incertezas acerca dos instrumentos legais pertinentes. Observou-se que em um cenário de incertezas sobre os efeitos danosos quando da utilização do OGM, o uso inconsequente e irresponsável da tecnologia tem provocado impactos diversos, causando ao meio ambiente impactos e danos de complexa mensuração. Neste sentido, também foram verificados a aplicabilidade da proteção ambiental face à implantação dos OGMs no meio ambiente, pelo Princípio da Precaução, acima de qualquer inferência. Assim, foi realizada uma revisão de literatura visando trazer para a sociedade, um levantamento estruturado sobre o uso do OGM e os eventuais prejuízos à biodiversidade. Portanto, a preocupação com o meio ambiente e a biodiversidade assumiu posição de destaque, sendo o cerne de toda a proteção jurídica com maior aplicabilidade do Direito. Por uma legislação mais objetiva, foi tratada a Lei de Biossegurança, para que as populações urbana e rural, entre outras, tenham seus direitos assegurados quanto à saúde ambiental. A partir das referências analisadas, tais como livros, websites, jornais, revistas científicas, entrevistas e documentários, verificou-se a existência dos riscos ambientais a que podem nos remeter os OGMs, bem como de seus efeitos e sérias consequências, potencialmente devastadoras para a preservação e continuidade de nossa biodiversidade. Por fim, foi possível concluir que a aplicabilidade da hipótese levantada, o Princípio da Precaução, deve ser sempre considerada nas questões pertinentes à proteção do meio ambiente e como instrumento de prevenção aos riscos e impactos ambientais decorrentes dos OGMs. / The use of Genetically Modified Organisms (GMOs) in agriculture has been the target of attention of the international community, reverberating greatly in the different areas of human knowledge. In front of the several questions resulting from the intensive use of these organisms and the effects it has generated to the environment, the present research sought to analyze the historical, technical and social aspects related to the subject in question, noticing all the uncertainties about the relevant legal provisions. In a scenario of uncertainties about the harmful effects of the use of GMO, it was observed that the inconsequent and irresponsible use of the technology has provoked several impacts, it has been causing to the environment impacts and damages of complex measurement. In this regard, the applicability of the environmental protection in the light of the implantations of GMOs in the environment as also been verified, by the Precautionary Principle, above any inference. Accordingly, a revision of literature was made aiming to bring to society a structured survey about the use of GMO and the eventually hazards to the biodiversity. Therefore, the concern with the environment and biodiversity has won a prominent position and has become the center of all of the legal protection with most applicability of Law. For a more objective legislation, the Biosafety Law was discussed in order that the urban and rural population, among others, have theirs rights secured regarding the environment health. From the analyzed references, such as book, websites, journals, scientific magazines, interviews and documentaries, the existence of environmental risks that the GMOs can refer us was verified, as well as their effects and serious consequences, potentially devastating for the preservation and continuity of ours biodiversity. Lastly, it was possible to conclude that the applicability of the raised hypothesis, the Precautionary Principle, must always be considered in the relevant issues regarding the environment protection and as a device of risk and impact prevention, resulting from the GMOs.
278

Interações da proteína Vip3Aa20, Diatraea saccharalis (Fabricius) e seus parasitóides, Cotesia flavipes (Cameron) e Trichogramma galloi Zucchi /

Lohmann, Tiago Rodrigo. January 2011 (has links)
Orientador: Odair Aparecido Fernandes / Banca: Celso Omoto / Banca: Ricardo Antonio Polanczyk / Resumo: O objetivo do presente estudo foi avaliar o efeito da proteína Vip3Aa20, originária da bactéria Bacillus thuringiensis Berliner, sobre a broca-do-colmo Diatraea saccharalis (Fabricius) e dois de seus parasitóides: o parasitóide larval Cotesia flavipes (Cameron) e o parasitóide de ovos Trichogramma galloi Zucchi. D. saccharalis mostrou-se suscetível à proteína, apresentando efeitos letais e subletais. Foram afetadas pela proteína as características mortalidade larval, duração do período larval, número de ínstares larvais e peso de larvas, enquanto que a mortalidade pupal e a duração do período pupal não foram afetadas e o peso de pupas apresentou resultados divergentes entre os bioensaios conduzidos. Para os parasitóides, avaliaram-se os efeitos da exposição direta (ingestão da proteína pelos adultos) e indireta (ingestão da proteína por D. saccharalis e posterior parasitismo). Em C. flavipes, não foram observados efeitos pela exposição direta, enquanto que na exposição indireta ocorreu efeito negativo sobre as características peso da massa de casulos e peso do adulto. Estes efeitos podem ser associados ao efeito mediado pelo hospedeiro. Em T. galloi, não foram observados efeitos da proteína Vip3Aa20 sobre os parasitóides, tanto na exposição direta como na indireta / Abstract: The aim of this study was to evaluate the effect of Vip3Aa20 protein, originating from the Bacillus thuringiensis Berliner bacterium, on sugarcane borer Diatraea saccharalis (Fabricius) and two of its parasitoids: larval parasitoid Cotesia flavipes (Cameron) and egg parasitoid Trichogramma galloi Zucchi. D. saccharalis was susceptible to protein, with lethal and sublethal effects. Larval mortality, larval period, number of instars and larval weight were affected by the protein, while pupal mortality and pupal period were not affected and pupal weight presented discrepant results between bioassays conducted. For the parasitoids, direct (protein ingested by adults) and indirect (protein ingested by sugarcane borer with later parasitism) exposure were evaluated. In C. flavipes, no effects were observed by direct exposure, while in indirect exposure negative effects occurred on the cocoons weight and adult weight. These effects may be associated with the effect mediated by the host. No effects were verified on T. galloi when this species was direct or indirectly exposed to Vip3Aa20 protein / Mestre
279

Avaliação da metodologia de detecção e quantificação por PCR em tempo real de organismos geneticamente modificados em alimentos: aspectos de produção, processamento e amostragem / Evaluation of real-time PCR detection and quantification methodology of genetically modified organisms in food: production, processing and sampling aspects

Denise Mayumi Cobaiashi 23 March 2012 (has links)
O recente crescimento da produção de organismos geneticamente modificados (OGM) no mundo tem demandado novas políticas de controle de plantio e comercialização de produtos alimentícios produzidos com ingredientes GM. Vários aspectos influenciam a análise de detecção e quantificação de OGM em alimentos, e em última instância, o monitoramento e atendimento à legislação e rotulagem. Este estudo se propôs a avaliar três destes aspectos, através da metodologia de análise de PCR em tempo real: a degradação de DNA e a presença adventícia de culturas GM e não-GM, ambas decorrentes da produção e processamento dos grãos em matérias-primas e produtos para consumo, bem como os planos de amostragem existentes para coleta de material alimentício destinado às análises de OGMs. Resultados demonstraram que os processos de fabricação degradam o material genético em diferentes graus em algumas matrizes de alimentos, viabilizando ou não, a análise por PCR em tempo real. Na cadeia de manufatura de subprodutos de soja, milho, arroz e trigo, 45% das amostras apresentaram detecção para uma cultura diferente da principal, sendo 44% deste total, GM. A adoção de metodologias de análise que se restringem à detecção de poucos genes-alvo, ou aplicadas somente a amostras compostas de soja ou milho, já não são mais suficientes para o rastreamento e quantificação dos alimentos contendo matérias-primas geneticamente modificadas. O plano de amostragem proposto foi representativo e delineado sob medida para avaliação de bebida à base de soja produzida em escala industrial, porém mais matrizes necessitam ser testadas para uma avaliação global das estratégias de amostragem. / The recent increase in genetically modified organisms (GMO) production is requiring new control policies for cultivation and commercialization of food products containing GM ingredients. There are many factors that can influence detection and quantification of GMO ingredients in food products, and these can ultimately influence the monitoring, labeling and legislation observance. In this work, we intended to evaluate three of these factors, using real-time PCR analysis method: DNA degradation; adventitious presence of GM and non-GM cultures, both caused by grain production and raw materials and finished products processing; and the available sampling plans for the collection of food material for GM analysis. Results in some food matrices showed that the manufacturing processes can degrade the genetic material in different degrees, allowing or not, the real-time PCR analysis. Regarding the soya beans, maize, rice and wheat manufacturing chains, 45% of the samples presented positive detection for a secondary crop, of which 44% were GM. The adoption of analysis methodologies restricted to a few target-genes, or applied solely to samples composed by soya or maize is simply not enough for tracking and quantification of food containing GM raw material. The sampling plan was representative and fit-for-purpose for one tested soya-based beverage and produced in industrial scale, however, more lots and matrices need to be analyzed for a global evaluation of the sampling strategies.
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Efeitos do algodão Bt (Bollgard evento 531) na comunidade bacteriana da rizosfera. / Effect of Bt cotton (Bollgard event 531) on the bacterial community of the rhizosphere.

Luciana Aparecida Avila 30 January 2008 (has links)
O algodão transgênico Bollgard® (algodão Bt) contém o gene cry1Ac da bactéria Bacillus thuringiensis, que confere a planta resistência a Lepidopteros. A expressão deste gene na planta pode acarretar efeitos ecológicos adversos à microbiota do solo e da rizosfera. Em casa-de-vegetação, a comunidade bacteriana associada ao algodão Bt foi comparada a do algodão convencional, em dois tipos de solos e quatro estádios fenológicos. Amostras de rizosfera foram avaliadas por técnicas dependentes e independentes de cultivo. As técnicas de contagem de bactérias e DGGE permitiram observar os efeitos do algodão Bt na densidade e diversidade de Pseudomonas e bactérias totais, durante os estádios iniciais de desenvolvimento da planta. A toxina Cry foi detectada na rizosfera de algodão Bt, em todo ciclo da cultura. Nas fases de formação do botão floral e abertura das maçãs, a atividade microbiana foi maior na rizosfera do algodão Bt. Esses resultados indicam o potencial do ambiente rizosférico em reestabelecer à estrutura da comunidade bacterina após um impacto temporal. / The transgenic cotton Bollgard® (Bt cotton) contains the cry1Ac gene from the Bacillus thuringiensis bacterium, which confers the plant resistance against some insects. The expression of this gene in the plant can cause adverse ecological effects on soil and rhizosphere microbiota. In a greenhouse experiment, the bacterial community associate to Bt cotton was compared to non-transgenic parental cultivar plants, in two types of soil at different plant development stages. Rhizosphere communities were evaluated by culture-dependent and independent approaches. Results reveal the effect of the Bt cotton in the density and diversity of Pseudomonas and total bacteria, during initial plant development stages. The Cry toxin was detected in the rhizosphere of Bt cotton, during all plant cycle. In the phases of flower formation and fruit opening, the microbial activity was greater in the rhizosphere of Bt cotton. These results show the potential of the rhizosphere to reestablish the original structure of the bacterial community after a temporary impact.

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