343 research outputs found
Introdução de plantas transgênicas no Brasil: basta avaliar o risco ambiental?
Em 12 de agosto de 2003, numa decisão liminar da Justiça Federal, o plantio e a comercialização de cinco variedades de soja transgênica foram autorizados para todo o Brasil. A decisão da liminar fez o governo federal discutir a edição imediata de uma Medida Provisória que autorizasse o plantio de soja transgênica na safra 2003/2004, considerando, sobretudo, a situação no Estado do Rio Grande do Sul, onde, aparentemente, não era mais possível evitar o plantio de soja transgênica em larga escala. Todavia, de acordo com Marina Silva, a Ministra do Meio Ambiente, "a liminar não libera a concessão de licenciamento e Estudo de Impacto Ambiental (EIA) pelo Ibama para qualquer empreendimento ou pessoa que pretenda desenvolver uma atividade produtiva ou de pesquisa com organismos geneticamente modificados". Em Nota a respeito, o Ministério lamentou a decisão, "pois a liberação do plantio da soja transgênica pode causar sérios riscos (grifo meu) para o meio ambiente do Brasil, tendo em vista não terem sido realizados estudos [dos impactos] ambientais [da introdução dessas plantas] em nosso país"
Modelling the Effect of Process Parameters on the Wet Extrusion and Spheronisation of High-Loaded Nicotinamide Pellets Using a Quality by Design Approach
Open access articleThe aim of the present study was to develop an alternative process to spray granulation in order to prepare high loaded spherical nicotinamide (NAM) pellets by wet extrusion and spheronisation. Therefore, a quality by design approach was implemented to model the effect of the process parameters of the extrusion-spheronisation process on the roundness, roughness and useable yield of the obtained pellets. The obtained results were compared to spray granulated NAM particles regarding their characteristics and their release profile in vitro after the application of an ileocolon targeted shellac coating. The wet extrusion-spheronisation process was able to form highly loaded NAM pellets (80%) with a spherical shape and a high useable yield of about 90%. However, the water content range was rather narrow between 24.7% and 21.3%. The design of experiments (DoE), showed that the spheronisation conditions speed, time and load had a greater impact on the quality attributes of the pellets than the extrusion conditions screw design, screw speed and solid feed rate (hopper speed). The best results were obtained using a low load (15 g) combined with a high rotation speed (900 m/min) and a low time (3–3.5 min). In comparison to spray granulated NAM pellets, the extruded NAM pellets resulted in a higher roughness and a higher useable yield (63% vs. 92%). Finally, the coating and dissolution test showed that the extruded and spheronised pellets are also suitable for a protective coating with an ileocolonic release profile. Due to its lower specific surface area, the required shellac concentration could be reduced while maintaining the release profil
Development and Validation of an In‐Line API Quantification Method Using AQbD Principles Based on UV‐Vis Spectroscopy to Monitor and Optimise Continuous Hot Melt Extrusion Process
open access journalA key principle of developing a new medicine is that quality should be built in, with a
thorough understanding of the product and the manufacturing process supported by appropriate
process controls. Quality by design principles that have been established for the development of
drug products/substances can equally be applied to the development of analytical procedures. This
paper presents the development and validation of a quantitative method to predict the
concentration of piroxicam in Kollidon® VA 64 during hot melt extrusion using analytical quality
by design principles. An analytical target profile was established for the piroxicam content and a
novel in‐line analytical procedure was developed using predictive models based on UV‐Vis
absorbance spectra collected during hot melt extrusion. Risks that impact the ability of the analytical
procedure to measure piroxicam consistently were assessed using failure mode and effect analysis.
The critical analytical attributes measured were colour (L* lightness, b* yellow to blue colour
parameters—in‐process critical quality attributes) that are linked to the ability to measure the API
content and transmittance. The method validation was based on the accuracy profile strategy and
ICH Q2(R1) validation criteria. The accuracy profile obtained with two validation sets showed that
the 95% β‐expectation tolerance limits for all piroxicam concentration levels analysed were within
the combined trueness and precision acceptance limits set at ±5%. The method robustness was tested
by evaluating the effects of screw speed (150–250 rpm) and feed rate (5–9 g/min) on piroxicam
content around 15% w/w. In‐line UV‐Vis spectroscopy was shown to be a robust and practical PAT
tool for monitoring the piroxicam content, a critical quality attribute in a pharmaceutical HME
process
Estratégia reprodutiva do maracujá amarelo (Passiflora edulis Sims F. flavicarpa Deg) em área irrigada do Vale do Submédio São Francisco.
O objetivo deste trabalho foi verificar a estratégia reprodutiva de P. edulis, em cultivo irrigado no projeto Maniçoba, em JuazeiroBA
Nocturnal bee pollinators are attracted to guarana flowers by their scents.
Floral scent is an important component of the trait repertoire of flowering plants, which is used to attract and manipulate pollinators. Despite advances during the last decades about the chemicals released by flowers, there is still a large gap in our understanding of chemical communication between flowering plants and their pollinators. We analyzed floral scents of guarana (Paullinia cupana, Sapindaceae), an economically important plant of the Amazon, using chemical analytical approaches, and determined the attractiveness of the scent to its nocturnal bee pollinators using behavioral assays in the field. Pollen loads of attracted bees were also analyzed. Inflorescences of guarana emit strong scents, both during day and at night, with some semi-quantitative differences between day- and night-time scents
Postpartum incidental solid pseudopapillary tumor of the pancreas : case report
Solid pseudopapillary tumors of the pancreas are usually described as rare lesions with low malignant potential and unpredictable behavior. The prognosis may be favorable even with local or distant dissemination. Despite the steady increase of cases diagnosed, the pathogenesis of this neoplasm remains unclear. We present a case of an incidental tumor discovered because of an acute abdomen in a postpartum woman without previous evidence of a tumor during the pregnancy
Atualizações em calagem de solos em Rondônia.
Este artigo trata da degradação química dos solos e apresenta métodos de recomendação de calagem.Editado por: Paulo Guilherme Salvador Wadt; Alaerto Luiz Marcolan; Stella Cristiani Gonçalves Matoso e Marcos Gervasio Pereira
Caracterização de dez áreas com café conilon arborizado na Zona da Mata de Rondônia.
A presente pesquisa faz parte de um projeto maior de manejo da lavoura cafeeira arborizada e objetivou identificar as principais espécies utilizadas na arborização de áreas com cafeeiro Robusta nos município de Rolim de Moura e Nova Brasilândia do Oeste. A pesquisa foi desenvolvida em dez propriedades, cinco por município, e constou da aplicação de um questionário sócio-econômico, no qual foram levantadas a área total de cada propriedade, área com café Robusta, área com a(s) espécie(s) arborizadora, número de plantas, produtividade e idade do cafeeiro. Em Rolim de Moura a área total das propriedades avaliadas com cafeeiro Robusta arborizado é de 7,9 ha, a produtividade média varia de 10 a 100 sacas/ha, a idade do cafeeiro varia de 5 a 15 anos. No município de Nova Brasilândia a área total com café nas propriedades analisadas é de 15, 58ha, produtividade variando de 9 a 85 sacas/ha, a idade do cafeeiro varia de 5 a 21 anos
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