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141.
Jos Agustín Tapia‐Hernndez Carmen Lizette Del‐Toro‐Snchez Francisco Javier Cinco‐Moroyoqui Saúl Ruiz‐Cruz Josu Jurez Daniela Denisse Castro‐Enríquez Carlos Gregorio Barreras‐Urbina Guadalupe Amanda Lpez‐Ahumada Francisco Rodríguez‐Flix 《Journal of food science》2019,84(4):818-831
Currently, electrospraying is a novel process for obtaining the nanoparticles from biopolymers. Zein nanoparticles have been obtained by this method and used to protect both hydrophilic and hydrophobic antioxidant molecules from environmental factors. The objective of this work was to prepare and characterize gallic acid‐loaded zein nanoparticles obtained by the electrospraying process to provide protection to gallic acid from environmental factors. Thus, it was related to the concentration of gallic acid in physicochemical and rheological properties of the electrosprayed solution, and also to equipment parameters, such as voltage, flow rate, and distance of the collector in morphology, and particle size. The physicochemical properties showed a relationship in the formation of a Taylor cone, in which at a low concentration of gallic acid (1% w/v), low viscosity (0.00464 ± 0.00001 Pa·s), and density (0.886 ± 0.00002 g/cm3), as well as high electrical conductivity (369 ± 4.3 µs/cm), forms a stable cone‐jet mode. The rheological properties and the Power Law model of the gallic acid‐zein electrosprayed solution demonstrated Newtonian behavior (n = 1). The morphology and size of the particle were dependent on the concentration of gallic acid. Electrosprayed parameters with high voltage (15 kV), low flow rate (0.1 mL/hr), and short distance (10 cm) exhibited a smaller diameter and spherical morphology. FT–IR showed interaction in the gallic acid‐loaded zein nanoparticle by hydrogen bonds. Therefore, the electrospraying process is a feasible technique for obtaining gallic acid‐loaded zein nanoparticles and providing potential protection to gallic acid from environmental factors. 相似文献
142.
Mercer Kelly E.; Ahn Christina E.; Coke Amanda; Compadre Cesar M.; Drake Richard R. 《Protein engineering, design & selection : PEDS》2002,15(11):903-911
Understanding the functional and mechanistic properties of themulti-substrate herpes simplex virus type-1 thymidine kinase(HSV-1 TK) remains critical to defining its role as a majorpharmacological target in herpesvirus and gene therapies forcancer. An inherent limitation of the activity of HSV-TK isthe >70-fold difference in the Kms for phosphorylation ofthymidine over the pro-drug ganciclovir (GCV). To engineer anHSV-1 TK isoform that is specific for GCV as the preferred substrate,16 site-specific mutants were generated. The mutations wereconcentrated at conserved residues involved in nucleoside basebinding, Gln125 and near sites 3 and 4 involved in catalysisand substrate binding. The substrate preferences of each mutantenzyme were compared with wild-type HSV-1 TK. One mutant, termedQ7530 TK, had a lower Km for GCV than thymidine. Expressionof the Q7530 TK in tumor cells indicated comparable metabolismto and improved sensitivity to GCV over wild-type HSV-1 TK,with minimal thymidine phosphorylation activity. A molecularmodeling simulation of the different HSV-1 TK active-sites wasdone for GCV and thymidine binding. It was concluded that mutationsat Gln125 and near site 4, especially at Ala168, were responsiblefor loss of deoxypyrimidine substrate binding. 相似文献
143.
Little is currently known about the significance of parents' unequal treatment of siblings and their relationships with their children; for example, are high levels of differential treatment consistently indicative of poorer parent-child relationships? Associations among differential parenting practices, perceptions of the fairness of these practices, and parent-child relationship quality were assessed from the perspectives of adolescent siblings and their parents in 74 maritally intact families. Multilevel random coefficient modeling revealed that the magnitude of differential treatment was associated with more negative parent-child relationships only when adolescents perceived differential treatment to be unfair. Differential treatment judged to be fair is not linked with negative parent-child relationships. Results highlight the importance of examining all family members' viewpoints about the legitimacy of differential treatment and of encouraging family members to discuss their understanding of these events. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
144.
Eisenberg Nancy; Sadovsky Adrienne; Spinrad Tracy L.; Fabes Richard A.; Losoya Sandra H.; Valiente Carlos; Reiser Mark; Cumberland Amanda; Shepard Stephanie A. 《Canadian Metallurgical Quarterly》2005,41(1):193
The relations of children's internalizing and externalizing problem behaviors to their concurrent regulation, impulsivity (reactive undercontrol), anger, sadness, and fearfulness and these aspects of functioning 2 years prior were examined. Parents and teachers completed measures of children's (N = 185; ages 6 through 9 years) adjustment, negative emotionality, regulation, and behavior control; behavioral measures of regulation also were obtained. In general, both internalizing and externalizing problems were associated with negative emotionality. Externalizers were low in effortful regulation and high in impulsivity, whereas internalizers, compared with nondisordered children, were low in impulsivity but not effortful control. Moreover, indices of negative emotionality, regulation, and impulsivity with the level of the same variables 2 years before controlled predicted stability versus change in problem behavior status. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
145.
Some industry analysts believe that the impact of pen-based computers—also referred to as notepad or stylus computers and electronic slates—rivals that of desktop machines. This column describes how pen-based computers work and offers some suggestions for IS managers who want to implement pen-based computers into the current work environment. 相似文献
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147.
Despite widespread speculation that syndrome co-occurrence undermines treatment outcomes, this hypothesis has not been fully examined within clinical care settings. To address this gap, the authors investigated the relation between syndrome co-occurrence and outcome among 325 clinically referred youths. For every syndrome, higher initial severity was predictive of greater treatment gains and higher posttreatment symptom levels; contrary to speculation in the literature, co-occurrence effects were rare and modest in size, accounting for 0.6% of outcome variance on average. The results suggest that co-occurrence, though common in youth clinical care, is not an obstacle to treatment success in most cases. In addition to its substantive findings, the study illustrates how a dimensional approach can be used to shed new light on co-occurrence in clinical care. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
Nathan K Cobb Amanda L Graham Beth C Bock George Papandonatos David B Abrams 《Nicotine & tobacco research》2005,7(2):207-216
To significantly reduce smoking prevalence, treatments must balance reach, efficacy, and cost. The Internet can reach millions of smokers cost-effectively. Many cessation Web sites exist, but few have been evaluated. As a result, the potential impact of the Internet on smoking prevalence remains unknown. The present study reports the results, challenges, and limitations of a preliminary, large-scale evaluation of a broadly disseminated smoking cessation Web site used worldwide (QuitNet). Consecutive registrants (N=1,501) were surveyed 3 months after they registered on the Web site to assess 7-day point prevalence abstinence. Results must be interpreted cautiously because this is an uncontrolled study with a 25.6% response rate. Approximately 30% of those surveyed indicated they had already quit smoking at registration. Excluding these participants, an intention-to-treat analysis yielded 7% point prevalence abstinence (for the responders only, abstinence was 30%). A range of plausible cessation outcomes (9.8%-13.1%) among various subgroups is presented to illustrate the strengths and limitations of conducting Web-based evaluations, and the tensions between clinical and dissemination research methods. Process-to-outcome analyses indicated that sustained use of QuitNet, especially the use of social support, was associated with more than three times greater point prevalence abstinence and more than four times greater continuous abstinence. Despite its limitations, the present study provides useful information about the potential efficacy, challenging design and methodological issues, process-to-outcome mechanisms of action, and potential public health impact of Internet-based behavior change programs for smoking cessation. 相似文献
149.
150.
30 high- and 30 low-hypnotizable Ss saw slides of a purse snatching and then imagined seeing the slides in hypnosis or waking conditions. The experimenter suggested the offender had a moustache (true), wore a scarf (false), and picked up flowers (false). Memory was tested by the experimenter after the suggestion, by another experimenter during an inquiry session, and again by the 2nd experimenter after the experimenter appeared to end the session. Hypnotizability, but not hypnosis, was associated with false memory reports; more high- than low-hypnotizable Ss reported false memories. The context of testing influenced true and false memory reports; fewer reports occurred in an informal rather than a formal test context. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献