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991.
Aline M. Bortoletto Ana Carolina Corrêa André R. Alcarde 《Journal of the Institute of Brewing》2016,122(2):293-298
The objective of this study was to evaluate the fatty acid profile and glycerol concentration in cachaças aged for 3 years in barrels made from different types of tropical woods and European oak. Glycerol gives body to spirits, whereas the fatty acid profile influences the spirit sensory characteristics. The concentration of these compounds in aged spirits depends on the wood composition. Tropical wood barrels made from amendoim (Pterogyne nitens Tul), araruva (Centrolobium tomentosum), cabreúva (Myrocarpus frondosus), cerejeira (Amburana cearensis), grápia (Apuleia leiocarpa), ipê roxo (Tabebuia heptaphylla), jequitibá (Cariniana estrellensis), jequitibá rosa (Cariniana legalis) and pereira (Platycyamus regnellii), as well as European oak (Quercus petraea), were used in this study. Glycerol concentrations in aged cachaças were measured using colorimetric methods, and fatty acid profiles were determined by GC‐MS analysis. The main fatty acids found were propanoic (C3:0), butanoic (C4:0), pentanoic (C5:0), octanoic (C8:0), decanoic (C10:0), dodecanoic (C12:0), hexadecanoic (C16:0), octadecanoic (C18:0) and octadecenoic (C18:19) acids. Araruva barrels stood out as the major supplier of C4:0 and cabreúva barrels provided greater amounts of C18:0 to cachaça. Carvalho and araruva barrels conferred more complete fatty acid profiles and higher concentrations of glycerol. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
992.
Children's early approaches to learning and academic trajectories through fifth grade. 总被引:2,自引:0,他引:2
Li-Grining Christine P.; Votruba-Drzal Elizabeth; Maldonado-Carre?o Carolina; Haas Kelly 《Canadian Metallurgical Quarterly》2010,46(5):1062
Children's early approaches to learning (ATL) enhance their adaptation to the demands they experience with the start of formal schooling. The current study uses individual growth modeling to investigate whether children's early ATL, which includes persistence, emotion regulation, and attentiveness, explain individual differences in their academic trajectories during elementary school. Using data from the Early Childhood Longitudinal Study – Kindergarten Cohort (ECLS-K), the present investigation examined the association between ATL at kindergarten entry and trajectories of reading and math achievement across 6 waves of data from kindergarten, 1st, 3rd, and 5th grade (n = 10,666). The current study found a positive link between early ATL and individual trajectories of reading and math performance. Overall, children's early ATL was equally beneficial for children regardless of their race/ethnicity and dimensions of their socioeconomic background. However, links between early ATL and academic trajectories differed by their gender and initial levels of math and reading achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
The typology, number, size, and distribution pattern of labellar and palpal sensilla of male and female Lutzomyia longipalpis (Lutz and Neiva, 1912) sand flies were analyzed by scanning electron and light microscopy, contributing to the construction of a gustatory and olfactory map in this important vector species. About 35 trichoid sensilla, sorted into three different classes according to their lengths, are present on the two labellar lobes. Five distinct structures are observed in the maxillary palps, which could be classified as noninnervated (microtrichia and scales) or the following innervated structures: 1) campaniform sensilla, found near the distal end of palpal segments II and III; 2) multiporous capitate peg sensilla, found in reduced number (1-6) on segment II, but located in a group of 15-25 on the distal third part of segment III; and 3) trichoid sensilla, distributed linearly on segment IV and spirally on segment V. Light microscopy analysis of silver-stained specimens indicated the presence of pores in the trichoid sensilla and their chemosensory function is discussed, as well as the possible function of the other sensilla. 相似文献
994.
Supercritical fluid extraction of potential migrants from paper and board intended for use as food packaging materials 总被引:1,自引:0,他引:1
The optimization of supercritical fluid extraction using CO2 for the extraction of contaminants in 15 samples of recycled paper and board (P&B) has been studied. An experimental design was used for simultaneous optimization of the variables involved in both the extraction step and the collection of the extract. Methanol was used as modifier. Several plastisizers such as diethyl phthalate, diisobutyl phthalate, di-n-butyl phthalate, dioctyl adipate, and diethylhexyl phthalate (from 2 to 100 microg/g of paper) were found in the recycled P&B samples. A discriminate analysis applied to all results obtained allow us to classify the samples in three different groups according to the content of recycled pulp (0, 10-30, and > 80% of recycled pulp), the sample thickness (from <300 to >600 microm), and the surface treatment of the paper. The analytical behavior and the results are discussed. 相似文献
995.
Calvo M Carazo M Arias ML Chaves C Monge R Chinchilla M 《Archivos latinoamericanos de nutrición》2004,54(4):428-432
The presence of Cyclospora sp., Cryptosporidium sp. and microsporidia and the levels of fecal coliforms were determined in lettuce, parsley, cilantro, strawberries and blackberries acquired in local agricultural markets of the Central Valley of Costa Rica, in order to establish the possible transmission risk of these microorganisms and other pathogens from the consumption of these raw products. During the second semester of 2001 and the first of 2002, 50 different samples of each product, 25 taken in the dry season and 25 in the rainy season and coming from five different local agricultural markets were evaluated. The fecal coliforms count was done according to the technique recommended by Vanderzant & Splittstoesser. The parasite determination was done using Zielh Nielsen and Weber staining techniques from a sediment obtained through the rinse of the mentioned products, using sterile peptonated water 0.1% and centrifuging at 900 G for 15 min. One hundred per cent of vegetable samples had fecal coliforms and the greatest prevalence was obtained during the rainy season. Although all vegetables presented fecal coliforms in high concentrations, lettuce and cilantro presented statistical difference between rainy and dry season, being greater during the rainy season. Fecal coliforms were not detected in strawberries and blackberries probablydue to its low pH. All products evaluated presented, at least once, Cryptosporidium sp., Cyclospora sp. and microsporidia, showing the risk they represent to Public Health. Cryptosporidium was present in all products but strawberries. Microsporidia was present in all products except blackberries and Cyclospora was only isolated from lettuce during the dry season. These results show the importance of introducing in the country Good Agricultural Practices, especially due to the resistance of Cryptosporidium and Cyclospora to disinfecting agents. 相似文献
996.
Ferreira PJ L'Abbate C Abrahamsohn PA Gouveia CA Moriscot AS 《Microscopy research and technique》2003,62(5):451-459
In order to further our understanding regarding the temporal and topographic ultrastructural aspects of the myocardium under thyrotoxicosis, thyroxine (T4; 25 and 100 microg/100 g bw) was administered to young rats 24 hours after birth until 15 days. The animals were then sacrificed, the hearts excised and weighed, and the ventricle tissue samples were then processed for confocal and transmission electron microscopy. At 48/72 hours and 1 week after initiation of T4 treatment with 100 microg/100 g bw, numerous lamellar bodies (probably formed by phospholipids) progressively accumulated in the heart. These bodies were observed in the cytosol, inside mitochondria and in the extracellular matrix. At 2 weeks of T4 treatment with 100 microg/100 g bw, lamellar bodies were virtually absent. Changes in cell shape, disorganization of intercellular junctions, and substantial myofibrillar disarray were observed in many cardiomyocytes. A gradient of myofibrillar disarray, which increased in abundance and intensity from the endocardium to the epicardium, was also observed. Immunocytochemical staining for desmin showed that the arrangement of this protein was disorganized in many cells of T4-treated rats as compared with normal ones, confirming ultrastructural data. The predominant appearance of myofibrillar disarray, associated with disorganization of cytoskeletal proteins in the deep myocardium, may be due to higher mechanical wall stress and consequent higher metabolic demand. Alternatively, differential sensitivity of cardiomyocytes to thyroid hormone in different areas is also a possibility. 相似文献
997.
The use of microwave ovens in food industry is a growing trend. It is used for thawing, drying and cooking food, but the microorganism's inactivation that this treatment may exert or not is still a subject of worldwide discussion. At the same time. Escherichia coli O157:H7 now presents itself as an emerging pathogen, distributed worldwide and associated with food. Its resistance to adverse environments has been widely discussed. The purpose of this work was to determine the effect of different times of exposure and cooking intensities of microwave oven on the survival of this bacterium inoculated into minced meat samples. These were inoculated with a high (10(7)-10(9) CFU/mL) or low (10(7)-10(7) CFU/mL) population of E. coli O157:H7, frozen for 3 days at-4 degrees C and thawed in a Whirlpool microwave oven according to their weight. They were radiated at levels of 70%, 80%, 90% and 100% for periods of 30, 60, 90 and 120 seconds. In each sample the rate of survival of the bacteria was determined according to the methodology described by Vanderzant & Splittstoesser. The results obtained showed that the rate of destruction of the bacteria analyzed was significant (p < 0.005). The number of bacteria present in the meat samples diminished dramatically as the exposure time and temperature increased, even though, for the complete elimination of this microorganism, a prolonged exposure was necessary, even though it did cause undesirable organoleptic characteristics in the food samples. 相似文献
998.
999.
1000.
Hana Kokot Boštjan Kokot Aleksandar Sebastijanović Carola Voss Rok Podlipec Patrycja Zawilska Trine Berthing Carolina Ballester-López Pernille Høgh Danielsen Claudia Contini Mikhail Ivanov Ana Krišelj Petra Čotar Qiaoxia Zhou Jessica Ponti Vadim Zhernovkov Matthew Schneemilch Zahra Doumandji Mojca Pušnik Polona Umek Stane Pajk Olivier Joubert Otmar Schmid Iztok Urbančič Martin Irmler Johannes Beckers Vladimir Lobaskin Sabina Halappanavar Nick Quirke Alexander P. Lyubartsev Ulla Vogel Tilen Koklič Tobias Stoeger Janez Štrancar 《Advanced materials (Deerfield Beach, Fla.)》2020,32(47):2003913
On a daily basis, people are exposed to a multitude of health-hazardous airborne particulate matter with notable deposition in the fragile alveolar region of the lungs. Hence, there is a great need for identification and prediction of material-associated diseases, currently hindered due to the lack of in-depth understanding of causal relationships, in particular between acute exposures and chronic symptoms. By applying advanced microscopies and omics to in vitro and in vivo systems, together with in silico molecular modeling, it is determined herein that the long-lasting response to a single exposure can originate from the interplay between the newly discovered nanomaterial quarantining and nanomaterial cycling between different lung cell types. This new insight finally allows prediction of the spectrum of lung inflammation associated with materials of interest using only in vitro measurements and in silico modeling, potentially relating outcomes to material properties for a large number of materials, and thus boosting safe-by-design-based material development. Because of its profound implications for animal-free predictive toxicology, this work paves the way to a more efficient and hazard-free introduction of numerous new advanced materials into our lives. 相似文献