51 research outputs found

    Solarization in microcosm: effect of plant materials on soil phytopathogen survival and volatile compound production

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    In addition to Brassicaceae species associated with soil solarization, new materials from plants such as cassava and castor bean have shown potential to control soil phytopathogens. Thus, the present study aimed to verify the effects of incorporation and decomposition of shoot of broccoli, castor bean, and bitter and sweet cassava, associated with solarization in microcosm sets under controlled environment conditions, on the survival of resistance structures from Fusarium oxysporum f. sp. lycopersici Race 2, Macrophomina phaseolina, Rhizoctonia solani AG-4 HGI and Sclerotium rolfsii; and to identify volatile compound(s) released by the decomposition of materials, which could be related to phytopathogen inactivation. As to pathogen survival, four identical assays were installed in the microcosms, with four independent exposure periods (7, 14, 21 and 28 days). To identify volatile compounds, assays were performed under the same survival conditions, but using amber glass bottles and gas chromatography with mass spectrometry (GC-MS) and flame ionization detectors (GC-FID), and adopting the Solid-Phase Microextraction Technique - SPME. The treatments soil+plant materials, over the tested periods, reduced the survival of resistance structures for all fungi. In general, expressive results were found for broccoli and bitter cassava, as well as sweet cassava against S. rolfsii. The identified volatile compounds were from broccoli, castor bean and sweet cassava decomposition. The number of volatile compounds identified for broccoli, castor bean and sweet cassava were 26, 37 and 29, respectively. Positive and negative correlations were detected among some volatile compounds and their mean values and the survival of resistance structures from phytopathogens.Além das brassicaceas associadas à solarização do solo, novos materiais vegetais como a mandioca e a mamona têm apresentado potencial no controle de fitopatógenos de solo. Assim, objetivou-se verificar os efeitos da incorporação e decomposição de parte aérea de brócolis, mamona e mandioca brava e mansa, associadas à solarização, em conjuntos de microcosmos, sob condições de ambiente controlado, na sobrevivência das estruturas de resistência de Fusarium oxysporum f. sp. lycopersici Raça 2, Macrophomina phaseolina, Rhizoctonia solani AG-4 HGI e Sclerotium rolfsii; e identificar e apontar o(s) volátil(eis) emanado(s) pela decomposição dos materiais, que poderia(m) estar correlacionado(s) com a inativação dos fitopatógenos. Quanto à sobrevivência dos patógenos, quatro ensaios idênticos foram instalados nos microcosmos, com quatro períodos de exposição independentes (7, 14, 21 e 28 dias). A identificação dos voláteis contou com ensaios realizados sob as mesmas condições da sobrevivência, mas em frascos âmbar e com cromatografia gasosa com detectores por espectrometria de massas (GC-MS) e por ionização em chama (GC-FID), utilizando a técnica de Microextração em Fase Sólida - SPME. Os tratamentos solo+materiais vegetais, ao longo dos períodos testados, reduziram a sobrevivência das estruturas de resistência de todos os fungos. No geral, destacaram-se o brócolis e a mandioca brava, além da mandioca mansa para S. rolfsii. Os voláteis identificados foram oriundos da decomposição de brócolis, mamona e mandioca mansa. Foram identificados 26, 37 e 29 compostos voláteis para brócolis, mamona e mandioca mansa, respectivamente. Correlações positivas e negativas foram observadas entre alguns voláteis e a média dos compostos com a sobrevivência das estruturas de resistência dos fitopatogênicos.123130Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Efeitos da restrição alimentar no desempenho de bovinos jovens confinados

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    The objective of the study was to evaluate compensatory weight gain in the performance of young bulls submitted to feed restriction, in the initial phase of confinement and to study the economic viability of the utilization of three protein sources. Sixty six crossbred bulls Simental-Nelore, eight months old and averaging 220 kg of weight were submitted to three feeding programs in the growth phase that lasted 84 days. The feeding programs were ad libitum, restriction + raw soybean grains and restriction + toasted soybean grains, with a restriction level of 25% on average. In the finishing phase, with a 61 day duration, animals fed with each of the three diets mentioned above received two types of supplementary diets: raw soybean grains and poultry litter. There were no differences between final weights of animals in finishing phase, but the bulls submitted to the restriction had more weight gain per day and better food conversion than ad libitum animals, for both raw soybean grains and poultry litter. The conclusion was that the feeding restriction and consequent compensatory weight gain, presented advantages for feeding efficiency, by decreasing maintenance requirements, although final cost had been equivalent to ad libitum animals.O trabalho objetivou avaliar as respostas do ganho compensatório no desempenho de animais mestiços jovens submetidos à restrição alimentar, na fase inicial de confinamento, e estudar a viabilidade econômica da utilização de três fontes protéicas. Foram utilizados 66 bovinos inteiros mestiços Simental-Nelore, com 8 meses e peso médio de 220±34,03 kg. Na fase de crescimento, com duração de 84 dias, os animais foram submetidos a três dietas alimentares: ad libitum (AL); restrição + soja crua (RSC) e restrição + soja torrada (RST), sendo o nível de restrição em torno de 25%. Na fase de terminação, com duração de 61 dias, os animais alimentados com cada uma das dietas citadas, receberam grãos de soja crus e cama de frango, como fonte suplementar de proteína. Os resultados mostraram que não houve diferenças entre os pesos finais dos animais, em fase de terminação. No entanto, os animais submetidos à restrição apresentaram maior ganho de peso diário e melhor conversão alimentar do que os ad libitum, em ambos os tratamentos, soja crua e cama de frango. Concluiu-se que a restrição alimentar com consequente ganho compensatório apresentou vantagens quanto aos índices de eficiência alimentar, por diminuir as exigências de manutenção, embora os custos finais tenham sido equivalentes aos dos animais ad libitum

    Effects of recombinant bovine somatotropin on performance and chemical characteristics of meat of bulls

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    O presente estudo objetivou avaliar as respostas da aplicação da somatotropina bovina recombinante (rbST) no ganho de peso, eficiência alimentar e características químicas da carne de bovinos jovens. Foram utilizados 59 bovinos inteiros: 30 mestiços Simmental x Nelore e 29 Nelores com idade entre sete a oito meses e pesos de 236 e 116 kg, respectivamente. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 2 x 2, com dois níveis de rbST (0 e 250 mg/animal/14 dias) e dois grupos raciais, subdivididos em duas fases experimentais. A dieta consistiu de silagem de milho e concentrado, balanceada para ganho diário de 0,8 kg na Fase I (70 dias) e 1,3 kg na Fase II (98 dias). Os animais foram abatidos aos 13 meses de idade e analisados quanto ao rendimento de carcaça e características químicas do músculo Longissimus dorsi. Os resultados mostraram que os animais mestiços superaram (P 0,05). A aplicação da rbST melhorou a eficiência alimentar em 11,91% nos mestiços e em 24,32% nos Nelore, na Fase II do experimento.The objective of this study was to evaluate the effects of the use of recombinant bovine somatotropin (rbST) in weight gain, feeding efficiency and chemical characteristics of meat of young bulls. Fifty nine young bulls were used: 30 crossbred Simmental x Nelore and 29 Nelore aging between seven to eight months, weighing 236 and 116 kg, respectively. A randomized experiment in a 2 x 2 factorial arrangement was used. There were two levels of rbST (0 and 250 mg/animal/14 days) and two breed groups subdivided in two experimental phases. Diet was based on corn silage and concentrate aiming at a weight gain of 0.8 a day for Phase I (70 days) and 1.3 kg for Phase II (98 days). Animals were slaughtered at 13 months of age and the measurements of carcass dressing and meat quality were taken. Results showed that cross-breeding animals overcame (p.05). The use of rbST improved feeding efficiency 11.91% for crossbred and 24.32% for Nelore in Phase II

    Toward Shared Decision-Making in Degenerative Cervical Myelopathy: Protocol for a Mixed Methods Study

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    BACKGROUND Health care decisions are a critical determinant in the evolution of chronic illness. In shared decision-making (SDM), patients and clinicians work collaboratively to reach evidence-based health decisions that align with individual circumstances, values, and preferences. This personalized approach to clinical care likely has substantial benefits in the oversight of degenerative cervical myelopathy (DCM), a type of nontraumatic spinal cord injury. Its chronicity, heterogeneous clinical presentation, complex management, and variable disease course engenders an imperative for a patient-centric approach that accounts for each patient's unique needs and priorities. Inadequate patient knowledge about the condition and an incomplete understanding of the critical decision points that arise during the course of care currently hinder the fruitful participation of health care providers and patients in SDM. This study protocol presents the rationale for deploying SDM for DCM and delineates the groundwork required to achieve this. OBJECTIVE The study's primary outcome is the development of a comprehensive checklist to be implemented upon diagnosis that provides patients with essential information necessary to support their informed decision-making. This is known as a core information set (CIS). The secondary outcome is the creation of a detailed process map that provides a diagrammatic representation of the global care workflows and cognitive processes involved in DCM care. Characterizing the critical decision points along a patient's journey will allow for an effective exploration of SDM tools for routine clinical practice to enhance patient-centered care and improve clinical outcomes. METHODS Both CISs and process maps are coproduced iteratively through a collaborative process involving the input and consensus of key stakeholders. This will be facilitated by Myelopathy.org, a global DCM charity, through its Research Objectives and Common Data Elements for Degenerative Cervical Myelopathy community. To develop the CIS, a 3-round, web-based Delphi process will be used, starting with a baseline list of information items derived from a recent scoping review of educational materials in DCM, patient interviews, and a qualitative survey of professionals. A priori criteria for achieving consensus are specified. The process map will be developed iteratively using semistructured interviews with patients and professionals and validated by key stakeholders. RESULTS Recruitment for the Delphi consensus study began in April 2023. The pilot-testing of process map interview participants started simultaneously, with the formulation of an initial baseline map underway. CONCLUSIONS This protocol marks the first attempt to provide a starting point for investigating SDM in DCM. The primary work centers on developing an educational tool for use in diagnosis to enable enhanced onward decision-making. The wider objective is to aid stakeholders in developing SDM tools by identifying critical decision junctures in DCM care. Through these approaches, we aim to provide an exhaustive launchpad for formulating SDM tools in the wider DCM community. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/46809
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