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131.
Effect of DAG on milk fat TAG crystallization   总被引:1,自引:0,他引:1  
The effect of milk fat and standard DAG on the crystallization behavior of milk fat TAG (MF-TAG) was investigated. When milk fat DAG were added to MF-TAG at the 0.1 wt% level, crystallization was delayed. Racemic purity was shown to be an important factor in the ability of DAG to influence TAG crystallization. Only sn-1,2 isomers of blends of MF-TAG with 0.1 wt% of the racemic mixtures of dipalmitin and diolein increased the activation free energy barrier to MF-TAG nucleation (ΔG c ) and delayed the subsequent crystallization process by increasing the crystallization induction time (τSFC) determined from solid fat content-time measurements. Although crystallization kinetics were affected, the properties of the resulting network structures remained unchanged upon addition of milk fat minor components at the 0.1 wt% level  相似文献   
132.
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   
133.
The authors reanalyzed assessment center (AC) multitrait-multimethod (MTMM) matrices containing correlations among postexercise dimension ratings (PEDRs) reported by F. Lievens and J. M. Conway (2001). Unlike F. Lievens and J. M. Conway, who used a correlated dimension-correlated uniqueness model, we used a different set of confirmatory-factor-analysis-based models (1-dimension-correlated Exercise and 1-dimension-correlated uniqueness models) to estimate dimension and exercise variance components in AC PEDRs. Results of reanalyses suggest that, consistent with previous narrative reviews, exercise variance components dominate over dimension variance components after all. Implications for AC construct validity and possible redirections of research on the validity of ACs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
134.
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   
135.
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   
136.
[Correction Notice: An erratum for this article was reported in Vol 16(3) of Psychology of Addictive Behaviors (see record 2009-17717-001). On page 121, in the abstract, the penultimate sentence incorrectly reads, “As predicted, participants consumed more alcohol following the anxiety challenge than following the control task; however, the opposite pattern was evidenced for drinking following the 2 activities.” The sentence should read as follows: “As predicted, participants consumed more alcohol following the anxiety challenge than following the control task; however, the opposite pattern was evidenced for drinking preceding the 2 activities.”] K. Abrams, M. Kushner, K. Medina, and A. Voight (2001) showed that alcohol attenuates social anxiety symptoms in socially phobic individuals. This article examines whether social anxiety symptoms can lead to increased alcohol use in this same population. Forty-four individuals with social phobia attended 2 laboratory sessions, spaced 1 week apart, in groups of approximately 10. Participants underwent a social anxiety challenge during 1 session and a control task during the other. Half of the sample self-administered alcohol immediately before, and half immediately after, these 2 activities. As predicted, participants consumed more alcohol following the anxiety challenge than following the control task; however, the opposite pattern was evidenced for drinking following the 2 activities. These findings add to an understanding of why social phobia and alcohol problems tend to co-occur. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
137.
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   
138.
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   
139.
140.
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   
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