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Evaluation of Indigenous Grains from the Peruvian Andean Region for Antidiabetes and Antihypertension Potential Using In Vitro Methods

RANILLA, Lena Galvez; APOSTOLIDIS, Emmanouil; GENOVESE, Maria Ines; LAJOLO, Franco Maria; SHETTY, Kalidas
Fonte: MARY ANN LIEBERT INC Publicador: MARY ANN LIEBERT INC
Tipo: Artigo de Revista Científica
ENG
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The health-relevant functionality of 10 thermally processed Peruvian Andean grains (five cereals, three pseudocereals, and two legumes) was evaluated for potential type 2 diabetes-relevant antihyperglycemia and antihypertension activity using in vitro enzyme assays. Inhibition of enzymes relevant for managing early stages of type 2 diabetes such as hyperglycemia-relevant alpha-glucosidase and alpha-amylase and hypertension-relevant angiotensin I-converting enzyme (ACE) were assayed along with the total phenolic content, phenolic profiles, and antioxidant activity based on the 1,1-diphenyl-2-picrylhydrazyl radical assay. Purple corn (Zea mays L.) (cereal) exhibited high free radical scavenging-linked antioxidant activity (77%) and had the highest total phenolic content (8 +/- 1 mg of gallic acid equivalents/g of sample weight) and alpha-glucosidase inhibitory activity (51% at 5 mg of sample weight). The major phenolic compound in this cereal was protocatechuic acid (287 +/- 15 mu g/g of sample weight). Pseudocereals such as Quinoa (Chenopodium quinoa Willd) and Kaniwa (Chenopodium pallidicaule Aellen) were rich in quercetin derivatives (1,131 +/- 56 and 943 +/- 35 mu g [expressed as quercetin aglycone]/g of sample weight, respectively) and had the highest antioxidant activity (86% and 75%...

Influence of temperature on continuous high gravity brewing with yeasts immobilized on spent grains

DRAGONE, Giuliano; MUSSATTO, Solange I.; SILVA, Joao B. Almeida e
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
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Flavor compounds` formation and fermentative parameters of continuous high gravity brewing with yeasts immobilized on spent grains were evaluated at three different temperatures (7, 10 and 15 degrees C). The assays were performed in a bubble column reactor at constant dilution rate (0.05 h(-1)) and total gas flow rate (240 ml/min of CO(2) and 10 ml/min of air), with high-gravity all-malt wort (15 degrees Plato). The results revealed that as the fermentation temperature was increased from 7 to 15 degrees C, the apparent and real degrees of fermentation, rate of extract consumption, ethanol volumetric productivity and consumption of free amino nitrogen (FAN) increased. In addition, beer produced at 15 degrees C presented a higher alcohols to esters ratio (2.2-2.4:1) similar to the optimum values described in the literature. It was thus concluded that primary high-gravity (15 degrees Plato) all-malt wort fermentation by continuous process with yeasts immobilized on spent grains, can be carried out with a good performance at 15 degrees C.

Collection of Pollen Grains by Centris (Hemisiella) tarsata Smith (Apidae: Centridini): Is C. tarsata an Oligolectic or Polylectic Species?

Goncalves, Lia; da Silva, Claudia Ines; Tunes Buschini, Maria Luisa
Fonte: ACAD SINICA INST ZOOLOGY; TAIPEI Publicador: ACAD SINICA INST ZOOLOGY; TAIPEI
Tipo: Artigo de Revista Científica
ENG
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Lia Goncalves, Claudia Ines da Silva, and Maria Luisa Tunes Buschini (2012) Collection of pollen grains by Centris (Hemisiella) tarsata Smith (Apidae: Centridini): Is C. tarsata an oligolectic or polylectic species? Zoological Studies 51(2): 195-203. Among pollinator species, bees play a prominent role in maintaining biodiversity because they are responsible, on average, for 80% of angiosperm pollination in tropical regions. The species richness of the bee genus Centris is high in South America. In Brazil, these bees occur in many types of ecosystems. Centris tarsata is an endemic species occurring only in Brazil. No previous studies considered interactions between plants and this bee species in southern Brazil, where it is the most abundant trap-nesting bee. Accordingly, the goals of this study were to investigate plants used by this species for its larval food supply and determine if this bee is polylectic or oligolectic in this region. This work was conducted in the Parque Municipal das Araucarias, Guarapuava (PR), southern Brazil, from Mar. 2002 to Dec. 2003. Samples of pollen were collected from nests of these bees and from flowering plants in grassland and swamp areas where the nests were built. All of the samples were treated with acetolysis to obtain permanent slides. The family Solanaceae was visited most often (71%). Solanum americanum Mill. (28.6%) and Sol. variabile Mart. (42.4%) were the primary pollen sources for C. tarsata in the study area. We found that although C. tarsata visited 20 species of plants...

TUNGSTEN ISOTOPIC COMPOSITIONS IN STARDUST SiC GRAINS FROM THE MURCHISON METEORITE: CONSTRAINTS ON THE s-PROCESS IN THE Hf-Ta-W-Re-Os REGION

Avila, Janaina N.; Lugaro, Maria; Ireland, Trevor R.; Gyngard, Frank; Zinner, Ernst; Cristallo, Sergio; Holden, Peter; Buntain, Joelene; Amari, Sachiko; Karakas, Amanda
Fonte: IOP PUBLISHING LTD; BRISTOL Publicador: IOP PUBLISHING LTD; BRISTOL
Tipo: Artigo de Revista Científica
ENG
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We report the first tungsten isotopic measurements in stardust silicon carbide (SiC) grains recovered from the Murchison carbonaceous chondrite. The isotopes (182,183,184,186)Wand (179,180)Hf were measured on both an aggregate (KJB fraction) and single stardust SiC grains (LS+ LU fraction) believed to have condensed in the outflows of low-mass carbon-rich asymptotic giant branch (AGB) stars with close-to-solar metallicity. The SiC aggregate shows small deviations from terrestrial (= solar) composition in the (182)W/(184)Wand (183)W/(184)Wratios, with deficits in (182)W and (183)W with respect to (184)W. The (186)W/(184)W ratio, however, shows no apparent deviation from the solar value. Tungsten isotopic measurements in single mainstream stardust SiC grains revealed lower than solar (182)W/(184)W, (183)W/(184)W, and (186)W/(184)W ratios. We have compared the SiC data with theoretical predictions of the evolution of W isotopic ratios in the envelopes of AGB stars. These ratios are affected by the slow neutron-capture process and match the SiC data regarding their (182)W/(184)W, (183)W/(184)W, and (179)Hf/(180)Hf isotopic compositions, although a small adjustment in the s-process production of (183)W is needed in order to have a better agreement between the SiC data and model predictions. The models cannot explain the (186)W/(184)W ratios observed in the SiC grains...

Efeitos do tempo e da temperatura de armazenamento de grãos de feijoeiro Phaseolus vulgaris L. na manifestação da resistência ao caruncho Acanthoscelides obtectus (Say, 1831)(Coleoptera: Bruchidae).; Effects of the time and temperature of storage bean grains Phaseolus vulgaris L. on the expression of the resistance to the bean weevil Acanthoscelides obtectus (Say, 1831) (Coleoptera: Bruchidae).

Baldin, Edson Luiz Lopes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/11/2001 PT
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Visando avaliar os efeitos do tempo e da temperatura de armazenamento de grãos de feijoeiro, Phaseolus vulgaris L., sobre a manifestação da resistência ao caruncho Acanthoscelides obtectus (Say, 1831), realizaram-se ensaios com e sem chance de escolha sob condições de laboratório. Em casa-de-vegetação avaliou-se a preferência para oviposição e os danos causados pelo caruncho em vagens e grãos. Os genótipos utilizados nos ensaios foram Arc.1S, Arc.3S, Arc.5S, Carioca Pitoco, Ipa 6, Porrillo 70, Onix, Arc.1, Arc.2, Arc.3 e Arc.4. Em teste com chance de escolha utilizando-se grãos de diferentes idades, observou-se que os genótipos selvagens Arc.1S e Arc.5S expressaram antibiose e/ou não-preferência para alimentação como mecanismos de resistência a A. obtectus; os genótipos Arc.1 e Arc.2 apresentaram somente antibiose; já Arc.3S expressou não-preferência para oviposição e baixos níveis de antibiose. Em teste sem chance de escolha, os genótipos Arc.1S, Arc.3S, Arc.5S, Arc.1 e Arc.2 expressaram antibiose. Em teste onde avaliou-se a influência do tamanho de grãos na manifestação da resistência, os genótipos selvagens Arc.1S, Arc.3S e Arc.5S expressaram antibiose e/ou não-preferência para alimentação; Arc.1 e Arc.2 expressaram antibiose. No estudo com grãos armazenados sob diferentes temperaturas observou-se antibiose em grãos de Arc.1S e Arc.2...

Levantamento da micoflora de grãos ardidos de milho e avaliação da resistência genética à Fusarium verticillioides; Survey of mycoflora in damaged corn grains and evaluation of genetic resistance to Fusarium verticillioides

Ramos, Adalgisa Thayne Munhoz
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/01/2009 PT
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Este trabalho teve dois objetivos distintos, o primeiro foi realizar um levantamento da micoflora associada a grãos ardidos de híbridos comerciais de milho pertencentes à empresa Dow AgroSciences e o outro foi avaliar linhagens de milho tropical para a resistência a podridão da espiga, incidência de grãos ardidos e produção de fumonisinas por Fusarium verticillioides. Para o primeiro objetivo, coletou-se grãos de dois híbridos (2B587 e 2B710) cultivados em diferentes localidades do Brasil durante a safra verão e safrinha, sob as zonas macro-climáticas SA (subtropical alta), SB (subtropical baixa), TA (tropical alta), TB (tropical baixa) e TT (tropical de transição) afim de, realizar a determinação da incidência fúngica através do método do papel de filtro com congelamento. O delineamento experimental foi inteiramente casualizado, com quatro repetições de 50 grãos de cada amostra. Os resultados indicaram Fusarium spp. e Penicillium spp. como os fungos de maior incidência nos grãos, sendo que na safra verão o comportamento dos híbridos em relação a incidência desses fungos variou de acordo com a zona climática. Na safrinha, o híbrido 2B710 foi o mais resistente a Fusarium spp. e Penicillium spp. independente da zona climática. Para o segundo objetivo...

O novo tempo do cerrado: expansão dos fronts agrícolas e controle do sistema de armazenamento de grãos; The new time of the cerrado: expansion of agricultural fronts and control of the storage of grains system

Frederico, Samuel
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/01/2009 PT
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O presente estudo analisa, numa perspectiva mais ampla, as principais características do novo tempo do Cerrado. Estas estão intimamente relacionadas à propagação dos fronts agrícolas, ou seja, da agricultura moderna, a partir da década de 1970. Esta agricultura, realizada de maneira intensiva e em larga escala, introduziu nos cerrados brasileiros um novo tempo, ao implantar sistemas técnicos extremamente funcionais à produção agrícola moderna, permitindo às grandes empresas um maior domínio da produção. Dentre os sistemas técnicos controlados pelas empresas, o sistema de armazenamento se destaca, ao configurar-se como um dos principais elos logísticos dos diversos circuitos espaciais produtivos agrícolas. Os silos permitem cadenciar a circulação dos grãos no tempo e no espaço, sendo imprescindíveis desde a produção (strictu sensu), até os estágios finais de exportação e consumo. Nos fronts agrícolas, o controle do sistema de armazenamento se torna ainda mais estratégico, por se tratar da principal região produtora de grãos do país, pela grande distância com relação aos portos exportadores e regiões consumidoras e pela precariedade dos sistemas de transporte. Esse contexto torna a posse do sistema de armazenamento um elemento chave para o controle da produção. É por isso que nas principais regiões produtoras a posse dos sistemas de armazenamento é ainda mais seletiva...

Efeitos da variação dos níveis de forragem em dietas contendo grãos de milho inteiro e os benefícios da floculação na terminação de tourinhos Nelore; Effects of various forage levels in feedlot diets containing whole corn grains and the benefits of corn flaking for finishing Nellore bulls

Marques, Rodrigo da Silva
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 03/08/2011 PT
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Foram utilizados 116 tourinhos da raça Nelore (373 Kg) distribuídos aleatoriamente em 20 baias, com o objetivo de comparar dietas com níveis crescentes de bagaço de cana de açúcar (0, 3, 6% da MS) com grãos de milho inteiro do tipo duro ou flint (69,5% de vitreosidade). Também foi incluso um tratamento com maior teor de proteína bruta por meio da adição de nitrogênio de liberação lenta (Optigen ®) e um quinto tratamento com milho floculado, ambos com 6% de bagaço. Os dados foram analisados em delineamento em blocos completos ao acaso, análises de regressão foram realizadas para os tratamentos que continham níveis crescentes de forragem e aplicação de contrastes ortogonais entre os tratamentos com milho inteiro com 6% de forragem Nas dietas com milho inteiro a inclusão de bagaço na dieta, aumentou a IMS (ingestão de matéria seca) de forma quadrática (P<0,05), aumentou o GPD (ganho de peso diário), o PF (peso corporal final) e o PCQ (peso de carcaça quente) de forma linear (P<0,05), mas não teve efeito (P>0,05) na eficiência alimentar (GPD/IMS). O aumento do teor de proteína da dieta com a adição de fonte de nitrogênio de liberação lenta não melhorou (P>0,05) o desempenho dos animais alimentados com grãos inteiro de milho. A floculação do milho melhorou (P<0...

Grãos de pólen anômalos no clone CP76 de Anacardium occidentale L. (Anacardiaceae); Anomalous pollen grains in the clone CP76 of Anacardium occidentale L. (Anacardiaceae)

Oliveira, Joao Marcelo Santos de; Mariath, Jorge Ernesto de Araujo; Bueno, Dalva Maria
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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Durante a investigação do desenvolvimento das anteras e grãos de pólen no clone CP76 de Anacardium occidentale foram observadas anomalias relacionadas ao desenvolvimento do gametófito masculino. Foram observados andrósporos que interromperam seu desenvolvimento momentos antes da primeira mitose, além de grãos que apresentaram anomalias relacionadas à fase inicial da gametogênese masculina. A primeira mitose anômala produziu grãos de pólen binucleados com células idênticas, ou quase, e ainda grãos onde a parede celular, oriunda da primeira mitose, foi incompletamente formada. Fusão nuclear foi observada nos grãos onde a parede celular foi incompletamente formada. A interrupção no desenvolvimento é muito freqüente, ao contrário das anomalias relacionadas à primeira mitose, de ocorrência muito rara.; Anomalies of male gametophyte development was observed during anther development investigation in the clone CP76 of Anacardium occidentale. Androspores that stop development before the first pollen mitosis, and grains that show male gametophyte anomalies in early stage of development, was observed. The anomalous first mitosis generate two identical cells, or quite, or grains where cell plate was partially formed. Nuclear fusion occurs in those cells where partial cell walls were formed. The interruption of development before first pollen mitosis occurs in high frequency...

Cryopreservation at-80A degrees C of Agaricus blazei on rice grains

Colauto, Nelson Barros; da Eira, Augusto Ferreira; Linde, Giani Andrea
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 3015-3018
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); The preservation of Agaricus blazei is generally done by mycelial subculturing, but this technique may cause genetic degenerations. Despite this, there is not an efficient protocol established to preserve this fungus and cryopreservation could be an alternative. This study aimed to evaluate two freezing protocols for cryopreservation at -80A degrees C of A. blazei strains. Five fungus strains grown on rice grains with husk and were transferred to glycerol (10%) in cryovials. Next, the cryovials were submitted to two freezing temperature protocols: (1) cryopreservation starting at 25A degrees C, then at 8A degrees C for 30 min and kept at -80A degrees C; (2) cryopreservation starting at 25A degrees C, then 8A degrees C for 30 min, -196A degrees C for 15 min and kept at -80A degrees C. After 1 year of cryopreservation, the cryovials were thawed in a water bath at 30A degrees C for 15 min and transferred to malt extract agar medium. It was concluded that the one-year cryopreservation process of A. blazei, grown on rice grains and cryopreserved at -80A degrees C in glycerol 10%, is viable. The slow freezing, from 8 to -80A degrees C, is effective whereas the fast freezing...

Spent-grains and zeolites as potential carriers for trypsin immobilisation

Rocha, Cristina M. R.; Ducso, L.; Gonçalves, M. P.; Teixeira, J. A.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2005 ENG
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Trypsin is a widely used enzyme for protein hydrolysis and can be used to improve functional and nutritional properties of foods. The immobilization of enzymes on solid supports can offer several advantages over free enzymes including easy handling, recovery from the reaction medium, reuse and operation in continuous reactors. Traditional carriers include porous silica, porous glass and cellulose derivatives. Zeolites are porous alumino-silicates available in a wide range of particle size and porosity and can also be used as carriers. Spent grains are a brewing by-product with a high content in cellulose and can also be interesting as carriers for enzyme immobilization because, besides having the necessary conditions (as stability, rigidity, low mass transfer limitations, for instance), they are cheap and food grade. This work proposes the use of spent grains and zeolites as alternative carriers for trypsin immobilization and compares them with a traditional support (silica). Physical adsorption, ionic attachment and covalent attachment to the supports were tested. The efficiency of immobilization and activity, as well as the operation and storage stability of free and immobilized enzyme on the three supports were studied. Trypsin was most successfully immobilized on the supports by covalent attachment using glutaraldehyde. Though the best efficiencies were still obtained with silica...

Physicochemical surface properties of brewing yeast influencing their immobilization onto spent grains in a continuous reactor

Brányik, Tomáš; Vicente, A. A.; Oliveira, Rosário; Teixeira, J. A.
Fonte: Wiley Periodicals, Inc. Publicador: Wiley Periodicals, Inc.
Tipo: Artigo de Revista Científica
Publicado em 05/10/2004 ENG
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Immobilization of brewing yeast onto a cellulosebased carrier obtained from spent grains, a brewing byproduct, by acid/base treatment has been studied in a continuously operating bubble-column reactor. The aim of this work was to study the mechanisms of brewing yeast immobilization onto spent grain particles through the information on physicochemical surface properties of brewing yeast and spent grain particles. Three mechanisms of brewing yeast immobilization onto spent grains carrier were proposed: cell-carrier adhesion, cell-cell attachment, and cell adsorption (accumulation) inside natural shelters (carrier’s surface roughness). The possibility of stable cell-carrier adhesion regarding the free energy of interaction was proved and the relative importance of longrange forces (Derjaguin-Landau-Verwey-Overbeek theory) and interfacial free energies was discussed. As for the cell-cell attachment leading to a multilayer yeast immobilization, a physicochemical interaction through localized hydrophobic regions on cell surface was hypothesized. However, neither flocculation nor chain formation mechanism can be excluded so far. The adsorption of brewing yeast inside sufficiently large crevices (pores) was documented with photomicrographs. A positive effect of higher dilution rate and increased hydrophobicity of base-treated spent grains on the yeast immobilization rate has also been found.; Fundação para Ciência e Tecnologia (FCT)

Immobilization of trypsin on spent grains for whey protein hydrolysis

Rocha, Cristina M. R.; Gonçalves, M. P.; Teixeira, J. A.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2011 ENG
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The aims of this work were to establish an efficient protocol for trypsin immobilization on spent grains and to assess the influence of the chosen protocol on whey protein hydrolysis. Trypsin was immobilized onto spent grain or modified spent grain, through adsorption and covalent attachment. The efficiency of immobilization and operation and storage stabilities of free and immobilized enzyme on the supports were studied. The enzyme activity, kinetic parameters and the peptide profile of the protein hydrolysates from free and immobilized enzyme were also analysed. The best activity retention was achieved with the immobilization on spent grains through multipoint covalent attachment using glycidol. This carrier showed also very good storage and operational stability (above 90%). Trypsin immobilized on spent grains showed significant activity towards whey proteins. The immobilized enzyme was slightly more stable than the free enzyme at temperatures between 50 °C and 60 °C allowing its use at a broader range of temperatures. The peptides formed with free enzyme and enzyme immobilized on spent grains were generally similar. However, significant differences existed in the amount of native proteins in the hydrolysates and in the relative amount of smaller peptides.

Effect of spent grains on flow regime transition in bubble column

Mota, André; Vicente, A. A.; Teixeira, J. A.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em 15/07/2011 ENG
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It is well known that two main flow regimes are present in bubble columns, being the evaluation of transition between homogeneous and heterogeneous regimes of crucial importance for reactor design. For air–water systems, several models have been satisfactorily proposed to explain this phenomenon. However when gas–liquid–solids systems are considered, solid particles influence on regime transition is not yet clear, in spite of the amount of research developed over the past years. The objective of this work is to evaluate the effect of a specific solid phase – spent grains – on homogeneous regime stability and regime transition. Spent grains are cellulose-based particles that have been used to immobilize cells on biotechnology process. These particles are wettable and have a density close to water and its influence on bubble column reactors is particularly important in order to establish the limits were both regimes prevail. A cylindrical Plexiglax BC of 18 L volume was used with air, water and spent grains at different concentrations (0–20% (wt.WET BASIS/vol.)) as gas, liquid and solid phases. Regime transition was determined according to the drift-flux and slip speed concept. It was found that at studied concentrations of spent grains...

The relationship between fungi growth and aflatoxin production with ergosterol content of corn grains

Castro,Maria Fernanda Penteado Moretzsohn de; Bragagnolo,Neura; Valentini,Sílvia Regina de Toledo
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2002 EN
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The relationships between fungal growth and ergosterol content and between aflatoxins B1 and B2 production and ergosterol content were verified in corn grains. In the first experiment, fungal growth and ergosterol content were monitored during incubation of corn grains presenting water activities of 0.85a w and 0.92a w at 25ºC over a period of 18 days. For the Taiúba variety, the fungi growth and ergosterol content increased more rapidly for 0.92a w than 0.85a w. Maximum ergosterol levels were 2.8 and 4.6 µg/g, respectively, for 0.85a w and 0.92a w. For the Cargill hybrid 606, a more pronounced increase in fungal growth was verified just at the end of the incubation period, mainly for 0.92a w when an acentuated increase in ergosterol content was also observed. Maximum ergosterol levels detected were 1.6 µg/g and 5.8 µg/g, respectively, for 0.85a w and 0.92a w. There was a significant correlation between ergosterol content and log of CFU g-1 for 0.92a w but not for 0.85 a w. In the second experiment, samples of corn grains of the Taiúba variety at 0.87a w and 0.95a w were inoculated with a toxigenic Aspergillus flavus strain and incubated at 25ºC. Ergosterol levels reached maximum values of 12.1 and 73.4 µg/g, respectively, for 0.87a w and 0.95a w. In both water activities...

Consumption of whole grains and cereal fiber and total and cause-specific mortality: prospective analysis of 367,442 individuals

Huang, Tao; Xu, Min; Lee, Albert; Cho, Susan; Qi, Lu
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN_US
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Background: Intakes of whole grains and cereal fiber have been inversely associated with the risk of chronic diseases; however, their relation with total and disease-specific mortality remain unclear. We aimed to prospectively assess the association of whole grains and cereal fiber intake with all causes and cause-specific mortality. Methods: The study included 367,442 participants from the prospective NIH-AARP Diet and Health Study (enrolled in 1995 and followed through 2009). Participants with cancer, heart disease, stroke, diabetes, and self-reported end-stage renal disease at baseline were excluded. Results: Over an average of 14 years of follow-up, a total of 46,067 deaths were documented. Consumption of whole grains were inversely associated with risk of all-cause mortality and death from cancer, cardiovascular disease (CVD), diabetes, respiratory disease, infections, and other causes. In multivariable models, as compared with individuals with the lowest intakes, those in the highest intake of whole grains had a 17% (95% CI, 14–19%) lower risk of all-cause mortality and 11–48% lower risk of disease-specific mortality (all P for trend <0.023); those in the highest intake of cereal fiber had a 19% (95% CI, 16–21%) lower risk of all-cause mortality and 15–34% lower risk of disease-specific mortality (all P for trend <0.005). When cereal fiber was further adjusted...

Assessing the uncertainty on particle size and shape: implications for ESR and OSL dating of quartz and feldspar grains

Duval, M.; Campaña, I.; Guilarte, V.; Miguens, L.; Iglesias, J.; González Sierra, S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: 7 pages
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Grain size and shape are two important parameters in Electron Spin Resonance (ESR) and Optically Stimulated Luminescence (OSL) dating of sediment, since they have a direct impact on several correction factors that are used for evaluating the dose rate. These parameters were evaluated by static image analysis for a wide range of quartz and feldspar grain samples. Our results indicate that there are many factors that may influence the final grain size and shape. Overall, grains are not perfect spheres, but should be rather approximated to smooth slightly elongated ellipsoids, with a width that is on average about 25% smaller than the length. For multiple grains dating, this may have an influence of a few percents on the beta dose rate evaluation, and thus even less on the total dose rate. However, in the case of single grain dating, the impact may be somewhat more significant given the large variability in size and shape between grains that may be encountered in a natural sediment. For beta micro-dosimetry purpose, it may be thus useful to better characterize the single grain that is going to be dated.; This study was partially sponsored by a project from the Spanish Ministry of Science and Innovation (Grant number: CGL2010- 16821). MD is currently the recipient of an International Outgoing Fellowship from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme (FP7/2007- 2013) under REA grant agreement PIOF-GA-2013-626474. IC is the beneficiary of a PhD scholarship from the Spanish MINECO (project CGL2012-38434-C03-02).

A State Trading Enterprise for Grains in Russia? Issues and Options

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Policy Note; Economic & Sector Work
ENGLISH; EN_US
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The impact of state trading enterprises (STEs) on domestic and international grain markets has been studied extensively over the years, generating a considerable body of theoretical and empirical evidence. The aim of this note is to draw on this body of evidence to analyze possible options for Russia's future state involvement in grain trade. The note covers the following three parts: i) outline of the potential economic impacts of STEs in grain trade from an economic perspective; ii) review of some of the global experience with STEs that are involved in grain exports; and iii) evaluation of options for state involvement in grain trade in Russia. The coverage in this note is limited to grains and to the impacts of STEs in countries that are net exporters of grain. Of the major grains, the note focuses on wheat which is by far the most important Russian export grain. Importing STEs are much more numerous than exporting STEs worldwide. However, unlike Ukraine, which has jumped between net export and net import situations for wheat as recently as 2003/04...

Optical Dating of Deep-Sea Sediments using Single Grains of Quartz: a Comparison with Radiocarbon

Olley, Jonathon; De Deckker, Patrick; Roberts, Richard; Fifield, L Keith; Yoshida, Hiroyuki; Hancock, Gary
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
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In this paper, we demonstrate that optical dating of single grains of quartz offers an alternative means of dating deep-sea sediments. The precision and accuracy of the technique, which has the potential to date sediments deposited during the last 500,000 years or so, is limited by the random and systematic uncertainties associated with producing optical ages. These result in total relative age uncertainties of between 10% and 20% at the 68% confidence interval, which are similar in size to those associated with Late Quaternary oxygen-isotope chronologies. We analysed single grains of quartz from several depth intervals down core Fr10/95-GC17, which was collected offshore from Cape Range Peninsula, Western Australia, from a water depth of 1093 m in the eastern Indian Ocean. The single-grain optical ages are shown to be consistent with AMS radiocarbon ages obtained from planktonic foraminifera from the same core. We also show that marine sediments are not immune from partial or heterogeneous bleaching (incomplete resetting) of the optical dating signal. Where partial or heterogeneous bleaching of the optical dating signal is indicated, we recommend that single-grain dating be employed and the burial dose estimated from the population of grains with the lowest absorbed radiation dose.

Microtextures on quartz grains in the beach sediments of Puerto Peñasco and Bahia Kino, Gulf of California, Sonora, Mexico

Madhavaraju,Jayagopal; García y Barragán,Juan Carlos; Mohammad Hussain,Shaik; Pachaiveedu Mohan,Saidapet
Fonte: Instituto de Geología, UNAM Publicador: Instituto de Geología, UNAM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2009 EN
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Beach sand samples collected from two localities of the Gulf of California (Puerto Peñasco and Bahia Kino, Sonora) were analyzed in order to identify their provenance and depositional history on the basis of the different microtextures on the quartz grains. The quartz grains were examined under a scanning electron microscope which brought out thirty two distinct microtextures that can be grouped into three modes of origin, i.e., mechanical (eighteen features), mechanical and/or chemical (five features) and chemical (seven features) origin. Among nine microtextures of chemical origin, two features are of dissolutional origin, whereas five features are characteristic of precipitational origin. Most of the microtextures are common in both areas (Puerto Peñasco and Bahia Kino) but frequency of occurrence slightly varies. Quartz grains from Puerto Peñasco and Bahia Kino show conchoidal fractures, straight steps and arcuate steps, which are characteristic features of quartz grains derived from crystalline source rocks. The presence of angular to subangular outline together with straight and arcuate steps indicates that these sediments have undergone short transportation and rapid deposition. V-shaped patterns, straight scratches and curved scratches...