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141.
Fl��via Santos Twardowski Pinto Simone Hickmann Fl?res Carolina Elisa Schneider Marco Antonio Z��chia Ayub Plinho Francisco Hertz 《Food and Bioprocess Technology》2011,4(4):559-565
In this work, the influence of oxygen mass transfer rates on the production of cyclodextrin glycosyltransferase (CGTase) by
the alkaliphilic bacterium Bacillus circulans ATCC 21783 was investigated. Experimental design and response surface methodology were applied to optimize agitation speed
and air flow rate in batch cultivations, in order to identify their significant effects and interactions with the synthesis
of CGTase. Results were expressed as the volumetric mass transfer rates of oxygen (kla, [per hour]). The maximal CGTase productivity of 155 U mL−1 h−1 was achieved with kla of 48 h−1. CGTase production was also studied in fed-batch cultures using the optimized parameters obtained in the batch experiments.
The maximal CGTase productivity on fed-batch cultivations was 137 U mL−1 h−1 with feeding rates of starch at 0.17 g L−1 h−1. 相似文献
142.
The problem of the characterisation of ancient mortars and plasters for restoration purposes is discussed and a methodology is proposed starting from the physical separation of the binder from aggregates. The procedure was applied to the plasters of the Ducal Palace in Mantua [Mantova] (Cavallerizza courtyard, XVI cent.): the results show the suitability of the proposed methodology for the determination of the plasters' nature, microstructure and even original formulation. 相似文献
143.
Francisco Prieto Manuela Rueda José Hidalgo Elisa Martínez Inmaculada Navarro 《Electrochimica acta》2011,(23):7916
The kinetics of azobenzene reduction on mercury electrodes in the absence of diffussional mass transport is studied by electrochemical impedance spectroscopy (EIS) in acetic acid/acetate buffered solutions at different pH values. Cyclic voltammetry experiments confirm the absence of diffusion effects and provide the values of the surface equilibrium potential. The analysis of the impedance frequency spectrums at every potential within the faradaic region conforms well the model and provides the global rate constant of the process, kf. The potential dependence of kf suggests the existence of an EE mechanism, with two electron transfers controlling the overall rate. The kinetic parameters of every step are obtained and their pH dependences clarify the role played by the protonation steps. 相似文献
144.
Stein Catherine H.; Abraham Kristen M.; Bonar Erin E.; Leith Jaclyn E.; Kraus Shane W.; Hamill Alexis C.; Gumber Shinakee; Hoffmann Erica; Fogo Wendy R. 《Canadian Metallurgical Quarterly》2011,25(3):449
The present intergenerational study examined the perceived impact of the recent U.S. economic crisis on a sample of 68 young adult–parent dyads. The relative contribution of perceived economic pressure, reports of adult child–parent relationship quality, and concerns about the economic future in accounting for variation in self-reports of psychological distress for adult children and their middle-aged parents were examined. Parents' concerns about their children's economic future accounted for variation in their reports of anxiety and depressed mood above and beyond that of perceived economic pressures and their views of the parent–child relationship. In contrast, for young adults, reports of personal economic pressure were generally related to self-reported anxiety and depressed mood. Implications of findings for research and practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
145.
Ciaramelli Elisa; Rosenbaum R. Shayna; Solcz Stephanie; Levine Brian; Moscovitch Morris 《Canadian Metallurgical Quarterly》2010,36(3):619
The ability to navigate in a familiar environment depends on both an intact mental representation of allocentric spatial information and the integrity of systems supporting complementary egocentric representations. Although the hippocampus has been implicated in learning new allocentric spatial information, converging evidence suggests that the posterior parietal cortex (PPC) might support egocentric representations. To date, however, few studies have examined long-standing egocentric representations of environments learned long ago. Here we tested 7 patients with focal lesions in PPC and 12 normal controls in remote spatial memory tasks, including 2 tasks reportedly reliant on allocentric representations (distance and proximity judgments) and 2 tasks reportedly reliant on egocentric representations (landmark sequencing and route navigation; see Rosenbaum, Ziegler, Winocur, Grady, & Moscovitch, 2004). Patients were unimpaired in distance and proximity judgments. In contrast, they all failed in route navigation, and left-lesioned patients also showed marginally impaired performance in landmark sequencing. Patients' subjective experience associated with navigation was impoverished and disembodied compared with that of the controls. These results suggest that PPC is crucial for accessing remote spatial memories within an egocentric reference frame that enables both navigation and reexperiencing. Additionally, PPC was found to be necessary to implement specific aspects of allocentric navigation with high demands on spontaneous retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
147.
Since the XIV century the Pio Palace in Carpi (MO, Italy) has been subjected to many additions and rearrangements and, in the last decades, to wide restoration works. Nevertheless the XVII century main portal has not been restored yet, due to its complex and peculiar surface alteration forms in comparison with the other parts of the building, and still suffers a deep decay and degradation by complex chemical-physical processes. 相似文献
148.
Valdir Mano Maria Elisa Scarpelli Ribeiro e Silva Niccoletta Barbani Paolo Giusti 《应用聚合物科学杂志》2004,91(1):501-505
Blends of poly(N‐isopropylacrylamide) (PNIPAM) and an ethylene/vinyl alcohol copolymer (EVAL) were obtained through casting from dimethyl sulfoxide (DMSO) solutions and phase inversion in 50/50 DMSO/H2O solutions. The miscibility and morphology of the PNIPAM/EVAL blends were investigated with thermal and morphological analysis. Differential scanning calorimetry indicated that the crystallinity of EVAL decreased with increasing PNIPAM content and that the blends cast from DMSO/H2O solutions were miscible in the melt state. Measurements of the melting point depression allowed the determination of the interaction energy density (B) and Flory–Huggins interaction parameter (χ12) with the Nishi–Wang equation. The negative B and χ12 values obtained were examined in terms of the specific intermolecular interactions between the polymers. Scanning electron micrographs revealed that blends obtained by the casting method led to dense membranes, whereas the phase‐inversion method rendered typical macroporous membranes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 501–505, 2004 相似文献
149.
Examined the effects of losing and regaining or gaining and relosing body weight in weight cycling (WC) vs weight maintenance (WM) on metabolic control. Ss were 327 adult male outpatient veterans (mean age 62.8 yrs) with non–insulin-dependent diabetes mellitus who were followed an average of 3.4 yrs. When compared with WM, WC, whether defined as a categorical or as a continuous variable, was not associated with deficits in metabolic control or increased need for hypoglycemic medication. Ss who weight cycled had fasting serum glucose and hemoglobin A1c levels comparable to those who remained within 10% of their initial body weights, and these levels of metabolic control were obtained with similar classes and dosages of hypoglycemic medication. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
150.