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81.
The KlLYS2 gene, encoding the alpha-aminoadipate reductase of Kluyveromyces lactis, was isolated by complementation of a lysA1 mutant. The deduced amino acid sequence shared an identity of 73% with the LYS2 product of Saccharomyces cerevisiae. Despite the high sequence homology of the alpha-aminoadipate reductase genes, the two yeast species differently responded to the presence of alpha-aminoadipate in the medium. Wild-type S. cerevisiae is known to be sensitive to alpha-aminoadipate, but becomes resistant when mutated to lys2. In contrast, K. lactis strains were found to be naturally resistant to alpha-aminoadipate. Therefore, the positive selection procedure for the isolation of lys2 mutants on alpha-aminoadipate, as practised in S. cerevisiae, cannot be applied to K. lactis. A possible reason of this difference may be that the catalytic rate of the alpha-aminoadipate reductase differs in the two yeasts. The EMBL/Genbank Accession No. for the KlLYS2 gene is AJ504405. 相似文献
82.
Barnan Das Diane J. Cook Maureen Schmitter-Edgecombe Adriana M. Seelye 《Personal and Ubiquitous Computing》2012,16(7):859-873
The growth in popularity of smart environments has been quite steep in the last decade and so has the demand for smart health assistance systems. A smart home-based prompting system can enhance these technologies to deliver in-home interventions to users for timely reminders or brief instructions describing the way a task should be carried out for successful completion. This technology is in high demand given the desire of people who have physical or cognitive limitations to live independently in their homes. In this paper, with the introduction of the “PUCK” prompting system, we take an approach to automate prompting-based interventions without any predefined rule sets or user feedback. Unlike other approaches, we use simple off-the-shelf sensors and learn the timing for prompts based on real data that are collected with volunteer participants in our smart home test bed. The data mining approaches taken to solve this problem come with the challenge of an imbalanced class distribution that occurs naturally in the data. We propose a variant of an existing sampling technique, SMOTE, to deal with the class imbalance problem. To validate the approach, a comparative analysis with cost-sensitive learning is performed. 相似文献
83.
Catarina Petisca Trinidad Pérez-Palacios Adriana Farah Olívia Pinho Isabel M.P.L.V.O. Ferreira 《Food and Bioproducts Processing》2013,91(3):233-241
The profile of major classes of furanic compounds, as well as other volatile compounds, was evaluated by headspace solid-phase microextraction GC/MS in Arabica ground coffee roasted at three speeds, and in their respective espresso coffees. A total of 113 and 105 volatile compounds were respectively identified in ground coffee and espresso coffee. They were clustered in the following chemical classes: furans, pyrroles, pyridines, pyrazines, ketones, hydrocarbons, aldehydes and others. Results from Principal Component Analysis (PCA) using the data of major volatile class as variables showed that the levels (expressed as relative percentage of total peak area) of furans and pyrroles were higher in espresso samples, whereas those of pyrazines and ketones were higher in ground samples. Slow roasting speed favoured pyridines formation, while medium and fast roasting speed favoured ketones formation. The most representative furanic compound in ground samples was furfuryl alcohol, followed by furfuryl acetate, 2-furfural, 2-methylfuran and 5-methylfurfural. In espresso samples, the levels of 2-methylfuran, 2-furfural, furfuryl formate, 5-methylfurfural and furfuryl acetate were largely increased while the proportion of furfuryl alcohol was strongly reduced in comparison to ground coffee. High roast speed increased formation of 2-furfural and 5-methyl furfural in espresso coffee. 相似文献
84.
In a quantitative meta-analysis, the effects of phonological awareness training on reading were shown. In a homogeneous set of U.S. studies with a randomized or matched design, the combined effect sizes for phonological awareness and reading were d?=?0.73 (r?=?.34, N?=?739) and d?=?0.70 (r?=?.33, N?=?745), respectively. Thus, experimentally manipulated phonological awareness explains about 12% of the variance in word-identification skills. The combined effect size for long-term studies of the influence of phonological awareness training on reading was much smaller, d?=?0.16 (r?=?.08, N?=?1,180). Programs combining a phonological and a letter training were more effective than a purely phonological training. Furthermore, training effects were stronger with posttests assessing simple decoding skills than with real-word-identification tests. In sum, phonological awareness is an important but not a sufficient condition for early reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
André O. Menezes Michelly T. Rodrigues Adriana Zimmaro Luiz E.P. Borges Marco A. Fraga 《Renewable Energy》2011,36(2):595-599
Aqueous-phase reforming of oxygenated hydrocarbons for hydrogen production presents several advantages as feed molecules can be easily found in a wide range of biomass, there is no need for its vaporization and the process allows thorough exploitation of the environmental benefits of using hydrogen as an energy carrier. The use of glycerol in particular is motivated due to its availability as a consequence of increasing biodiesel production worldwide. In this contribution, the performance of Pt-based catalysts supported on different oxides (Al2O3, ZrO2, MgO and CeO2) is studied on glycerol reforming. All catalysts led to a hydrogen-rich gas phase. However, a good potential activity with high production of hydrogen and low concentration of undesired hydrocarbons was accomplished over the catalysts supported on MgO and ZrO2. The high electron donating character of such oxides indicates the influence of the nature of the support in catalytic performance for glycerol reforming. 相似文献
86.
87.
Renan C. Chisté Marta T. Benassi Adriana Z. Mercadante 《International Journal of Food Science & Technology》2011,46(9):1863-1870
This study was conducted to obtain annatto extracts with both high antioxidant capacity and colour potential using solvents of different polarities (water, ethanol/water, ethanol, ethanol/ethyl acetate and ethyl acetate). The highest levels of total phenolic compounds were found in the water, ethanol/water and ethanol extracts (0.5 mg GAE mL?1), and the highest level of bixin was found in the ethanol/ethyl acetate extract (5.2 mg mL?1), which was characterised as the reddest and the most vivid one (a* = 40.5, h° = 46.1, C* = 58.4). The ethanol/ethyl acetate extract also showed the highest antioxidant activity (4.7 μm TEAC mL?1) and the highest percentage of tryptophan protection against singlet oxygen (63.6%). On the other hand, ethyl acetate and ethanol/water were the least effective solvents for the extraction of phenolic compounds and bixin, respectively. According to the multivariate statistical analysis, ethanol/ethyl acetate and ethyl acetate were the most promising solvents to obtain annatto extracts with both antioxidant and colour properties. 相似文献
88.
89.
Ana Paula R. Harbach Mara C.R. da Costa Adriana L. Soares Ana M. Bridi M. Shimokomaki Caio A. da Silva Elza I. Ida 《Food chemistry》2007,100(4):1630-1633
The effects of dietary defatted corn germ meal (DCGM) containing phytic acid (PA) on pig health during development and on its Longissimus dorsi m. (LD) lipid oxidative stability has been evaluated. Rations of DCGM were prepared at the level of substitution of 0%, 10%, 20% and 40% and offered to twenty four animals of Landrace x Large White crossbreds throughout 25 days before slaughtering. Animals were sacrificed at an average weight of 91.24 kg (±0.950) and samples for meat lipid oxidation analysis were taken after seven days under refrigeration at 3 °C. Animals fed with DCGM did not show any significant difference, in comparison to the control, in carcass characteristics, such as cold carcass weight, backfat depth, muscle depth, lean meat percentage and carcass dress yielding (p 0.05). Finally, no difference in meat proximate chemical composition was detected solely arising from lipid oxidation since LD from DCGM-treated pigs revealed an inhibition of 63.0%. 相似文献
90.
Writing and drawing produced by children 28-53 months old were compared. Israeli and Dutch preschoolers were asked to draw and write, to classify their products as drawing and writing, and to decide what they had drawn or written. Israeli and Dutch mothers classified the products. Scores on a scale for writing composed of graphic, "writing-like," and symbolic schemes showed improvement with age. Recognition of drawings as drawings preceded recognition of writings as writings. Scores on writing and drawing were substantially correlated, even with age partialed out, suggesting (a) that when children start drawing objects referentially, they write by drawing "print" and (b) that progress in object drawing involves progress in drawing print, so that their writing becomes more writing-like. Children unable to communicate meaning by writing spontaneously resort to drawing-like devices, indicating the primacy of drawing as a representational-communicative system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献