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31.
Beatriz Gutiérrez‐Rivera Krzysztof Waliszewski‐Kubiak Octavio Carvajal‐Zarrabal Maria Guadalupe Aguilar‐Uscanga 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(2):263-270
BACKGROUND: Efficient conversion of glucose/xylose mixtures from lignocellulose is necessary for commercially viable ethanol production. Oxygen and carbon sources are of paramount importance for ethanol yield. The aim of this work was to evaluate different glucose/xylose mixtures for ethanol production using S. cerevisiae ITV‐01 (wild type yeast) and P. stipitis NRRL Y‐7124 and the effect of supplying oxygen in separate and co‐culture processes. RESULTS: The complete conversion of a glucose/xylose mixture (75/30 g L?1) was obtained using P. stipitis NRRL Y‐7124 under aerobic conditions (0.6 vvm), the highest yield production being Yp/s = 0.46 g g?1, volumetric ethanol productivity Qpmax = 0.24 g L?1 h?1 and maximum ethanol concentration Pmax = 34.5 g L?1. In the co‐culture process and under aerobic conditions, incomplete conversion of glucose/xylose mixture was observed (20.4% residual xylose), with a maximum ethanol production of 30.3 g L?1, ethanol yield of 0.4 g g?1 and Qpmax = 1.26 g L?1 h?1. CONCLUSIONS: The oxygen present in the glucose/xylose mixture promotes complete sugar consumption by P. stipitis NRRL Y‐7124 resulting in ethanol production. However, in co‐culture with S. cerevisiae ITV‐01 under aerobic conditions, incomplete fermentation occurs that could be caused by oxygen limitation and ethanol inhibition by P. stipitis NRRL Y‐7124; nevertheless the volumetric ethanol productivity increases fivefold compared with separate culture. Copyright © 2011 Society of Chemical Industry 相似文献
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33.
Ana Beatriz Lopes de Sousa Jabbour Charbel José Chiappetta Jabbour Joseph Sarkis Kannan Govindan 《Clean Technologies and Environmental Policy》2014,16(1):7-9
Brazil, one of the world’s largest developing countries, has recently introduced a new solid waste management regulatory policy. This new regulatory policy will have implications for a wide variety of stakeholders and sets the stage for opportunities and lessons to be learned. These issues are discussed in this article. 相似文献
34.
Rafael Llobet Marina Pollán Joaquín Antón Josefa Miranda-García María Casals Inmaculada Martínez Francisco Ruiz-Perales Beatriz Pérez-Gómez Dolores Salas-Trejo Juan-Carlos Pérez-Cortés 《Computer methods and programs in biomedicine》2014
The task of breast density quantification is becoming increasingly relevant due to its association with breast cancer risk. In this work, a semi-automated and a fully automated tools to assess breast density from full-field digitized mammograms are presented. The first tool is based on a supervised interactive thresholding procedure for segmenting dense from fatty tissue and is used with a twofold goal: for assessing mammographic density (MD) in a more objective and accurate way than via visual-based methods and for labeling the mammograms that are later employed to train the fully automated tool. Although most automated methods rely on supervised approaches based on a global labeling of the mammogram, the proposed method relies on pixel-level labeling, allowing better tissue classification and density measurement on a continuous scale. The fully automated method presented combines a classification scheme based on local features and thresholding operations that improve the performance of the classifier. A dataset of 655 mammograms was used to test the concordance of both approaches in measuring MD. Three expert radiologists measured MD in each of the mammograms using the semi-automated tool (DM-Scan). It was then measured by the fully automated system and the correlation between both methods was computed. The relation between MD and breast cancer was then analyzed using a case–control dataset consisting of 230 mammograms. The Intraclass Correlation Coefficient (ICC) was used to compute reliability among raters and between techniques. The results obtained showed an average ICC = 0.922 among raters when using the semi-automated tool, whilst the average correlation between the semi-automated and automated measures was ICC = 0.838. In the case–control study, the results obtained showed Odds Ratios (OR) of 1.38 and 1.50 per 10% increase in MD when using the semi-automated and fully automated approaches respectively. It can therefore be concluded that the automated and semi-automated MD assessments present a good correlation. Both the methods also found an association between MD and breast cancer risk, which warrants the proposed tools for breast cancer risk prediction and clinical decision making. A full version of the DM-Scan is freely available. 相似文献
35.
The use of probiotic cultures in the production of Dutch-type cheeses did not lead to significant changes in their chemical composition but it lowered their acidity. The availability of calcium and magnesium analyzed by in vitro enzymatic hydrolysis was 19 and 35%, respectively; the availability of phosphorus was significantly higher, at >90%. The use of probiotic cultures significantly increased the availability of calcium (~2.5%), phosphorus (~6%), and magnesium (~18%). The in vitro method supports accurate determination of the effect of the Lactobacillus spp. cultures on the availability of mineral compounds ingested with Dutch-type cheese. 相似文献
36.
Multifunctional Silver‐Exchanged Zeolite Micromotors for Catalytic Detoxification of Chemical and Biological Threats 下载免费PDF全文
Virendra V. Singh Beatriz Jurado‐Sánchez Sirilak Sattayasamitsathit Jahir Orozco Jinxing Li Michael Galarnyk Yuri Fedorak Joseph Wang 《Advanced functional materials》2015,25(14):2147-2155
Multifunctional reactive‐zeolite‐based micromotors have been developed and characterized toward effective and rapid elimination of chemical and biological threats. The incorporation of silver ions (Ag+) into aluminosilicate zeolite framework imparts several attractive functions, including strong binding to chemical warfare agents (CWA) followed by effective degradation, and enhanced antibacterial activity. The new zeolite‐micromotors protocol thus combines the remarkable adsorption capacity of zeolites and the efficient catalytic properties of the reactive Ag+ ions with the autonomous movement of the zeolite micromotors for an accelerated detoxification of CWA. Furthermore, the high antibacterial activity of Ag+ along with the rapid micromotor movement enhances the contact between bacteria and reactive Ag+, leading to a powerful “on‐the‐fly” bacteria killing capacity. These attractive adsorptive/catalytic features of the self‐propelled zeolite micromotors eliminate secondary environmental contamination compared to adsorptive micromotors. The distinct cubic geometry of the zeolite micromotors leads to enhanced bubble generation and faster movement, in unique movement trajectories, which increases the fluid convection and highly efficient detoxification of CWA and killing of bacteria. The attractive capabilities of these zeolite micromotors will pave the way for their diverse applications in defense, environmental and biomedical applications in more economical and sustainable manner. 相似文献
37.
Kannan Govindan Devika Kannan K. Mathiyazhagan Ana Beatriz Lopes de Sousa Jabbour Charbel José Chiappetta Jabbour 《The International journal of environmental studies》2013,70(4):477-493
Industries need to adopt the environmental management concepts in the traditional supply chain management. The green supply chain management (GSCM) is an established concept to ensure environment-friendly activities in industry. This paper identifies the relationship of driving and dependence that exists between GSCM practices with regard to their adoption within Brazilian electrical/electronic industry with the help of interpretive structural modelling (ISM). From the results, we infer that cooperation with customers for eco-design practice is driving other practices, and this practice acts as a vital role among other practices. Commitment to GSCM from senior managers and cooperation with customers for cleaner production occupy the highest level. 相似文献
38.
Roseli de Souza Santos da Costa Flavia da Silva Santos Daniela de Barros Mucci Tânia Vignuda de Souza Fátima Lucia de Carvalho Sardinha Célia Regina Moutinho de Miranda Chaves Maria das Graças Tavares do Carmo 《Lipids》2016,51(12):1363-1373
The purpose of this study was to investigate the trans fatty acids (TFA) content and distribution in colostrum, mature milk, and diet of adolescent mothers, after TFA declaration in food labels became mandatory in Brazil. Participants were healthy adolescents (n 54, 15–19 years, 1–90 days postpartum) practicing exclusive breastfeeding. Milk samples were collected 3 days after delivery (colostrum) and in the third month postpartum (mature milk) by hand expression. The fatty acid composition of the milk samples was determined by gas chromatography. TFA intake corresponded to 1.23 % of total energy value. Total 18:2 TFA accounted for less than 0.5 % of the energy intake. The amount of total 18:1 TFA (mean ± SEM) was 1.9 % ± 0.14 in colostrum and 1.5 % ± 0.2 in mature milk. The total content of n‐3 PUFA was inversely correlated with the total content of 18:1 TFA in colostrum. Both in colostrum and in mature milk, vaccenic acid (11t‐18:1) was found to be the most abundant 18:1 trans isomer, followed by elaidic acid (9t‐18:1), whereas rumenic acid (9c,11t‐18:2 CLA) was the predominant 18:2 trans isomer. In conclusion, the levels of TFA of industrial sources found in the mother's diet and breast milk (colostrum and mature milk) showed a decrease in relation to those observed in studies conducted prior to the TFA labeling resolution in Brazil. However, the current low intake levels of n‐3 LCPUFA and DHA content in the milk of lactating adolescents may be insufficient for supporting adequate neurological development of the infants. 相似文献
39.
Beatriz Gandul-Rojas M Isabel Minguez-Mosquera 《Journal of the science of food and agriculture》1996,72(1):31-39
A study of chlorophyll and carotenoid composition of nine single-variety virgin olive oils from the main Spanish producing regions has shown differences depending on variety and ripening degree of the fruits. Pheophytin a was the major pigment in all the oils studied (44–58% total pigments), followed by lutein (18–38%) and β-carotene (6–17%). The chlorophyll pigments group also included pheophytin b and in some cases chlorophylls a and b . The carotenoid fraction also included the xanthophylls neoxanthin, violaxanthin, luteoxanthin, antheraxanthin, mutatoxanthin and β-cryptoxanthin. The mean provitamin A activity of the oils was 260 μg kg−1 expressed as retinol equivalent. cis -α-Carotene (tentative), mono- and di-esterified xanthophylls and pheophorbide a were pigments exclusive to Arbequina variety, a fact that could be used as a chemo-taxonomic differentiator of the oils of this variety. The ratio between the chlorophyll fraction and the carotenoid fraction was maintained in most cases around 1, demonstrating that the green and yellow fractions were in balance, notwithstanding their greater or lesser total pigment content. The considerable range in the lutein/β-carotene ratio (between 1·3 and 5·1 depending on variety) makes this ratio a differentiator of single-variety oils. Despite the different sources of the oils, some general trends have been shown which suggest what chlorophyll and carotenoid pigments should be expected in an olive oil so as to include it within the denomination ‘virgin’. 相似文献
40.
Maria Sofia Vieira-Rocha Pilar Rodriguez-Rodriguez Mariana Ferreira-Duarte Miguel Faria Joana Beatriz Sousa Manuela Morato Silvia Magdalena Arribas Carmen Diniz 《International journal of molecular sciences》2022,23(3)
Fetal stress is known to increase susceptibility to cardiometabolic diseases and hypertension in adult age in a process known as fetal programming. This study investigated the relationship between vascular RAS, oxidative damage and remodeling in fetal programming. Six-month old Sprague-Dawley offspring from mothers that were fed ad libitum (CONTROL) or with 50% intake during the second half of gestation (maternal undernutrition, MUN) were used. qPCR or immunohistochemistry were used to obtain the expression of receptors and enzymes. Plasma levels of carbonyls were measured by spectrophotometry. In mesenteric arteries from MUN rats we detected an upregulation of ACE, ACE2, AT1 receptors and NADPH oxidase, and lower expression of AT2, Mas and MrgD receptors compared to CONTROL. Systolic and diastolic blood pressure and plasma levels of carbonyls were higher in MUN than in CONTROL. Vascular morphology evidenced an increased media/lumen ratio and adventitia/lumen ratio, and more connective tissue in MUN compared to CONTROL. In conclusion, fetal undernutrition indices RAS alterations and oxidative damage which may contribute to the remodeling of mesenteric arteries, and increase the risk of adverse cardiovascular events and hypertension. 相似文献