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121.
Hoyt Tim; Pasupathi Monisha; Smith Bruce W.; Yeater Elizabeth A.; Kay Virginia S.; Tooley Erin 《Canadian Metallurgical Quarterly》2010,17(1):78
The disclosure of emotional events to various social intimates (disclosure targets) was measured in 2 samples (soldiers and first responders) at risk for posttraumatic stress disorder (PTSD), as well as a comparison sample of college students. These 3 groups completed survey measures of disclosure, and at risk groups also completed measures of PTSD symptoms and social support. Groups at risk for PTSD were less likely to disclose emotions related to potentially traumatic events than were college students reporting general emotional disclosure. Overall, disclosure of positive emotions was more likely than disclosure of negative emotions. Furthermore, amount of disclosure depended on the person to whom the individual disclosed. Within groups at risk for PTSD, social support was associated with lower levels of PTSD. However, this relationship was mediated by emotional disclosure to each target. Disclosure of positive emotions generally was associated with lower levels of PTSD, and disclosure of negative emotions to those with similar at-risk status was associated with greater levels of PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
122.
Virginia Stovin Ian Guymer Shing-Tak Douglas Lau 《Canadian Metallurgical Quarterly》2010,136(5):318-327
Solute transport processes affect the performance of a wide range of water engineering structures. In the context of urban drainage, the effects of dispersion may act to reduce peak concentrations associated with intermittent discharges or cause pollutants to be retained for longer or shorter durations than mean travel times would predict. With respect to surcharged manholes, previous research employed laboratory experiments to identify best-fit parameter values for the first-order advection-dispersion equation (ADE) and aggregated dead zone (ADZ) routing models. This paper presents data from a new set of smaller-scale laboratory measurements and demonstrates that the threshold depth separating two distinct hydraulic regimes can be identified independently of scale. However, the fitted ADE and ADZ routing model parameters are not generally amenable to conventional hydraulic scaling, because the models do not provide good fits to the observed data. An alternative approach is proposed based on the cumulative residence time distribution (CRTD). This approach is shown to be scalable and practical. The solute transport characteristics of a specific configuration of a surcharged manhole are shown to be characterized by just two dimensionless CRTDs corresponding to prethreshold and postthreshold surcharge depths. 相似文献
123.
Sara E. Olesiak Michelle L. Oyen Virginia L. Ferguson 《Mechanics of Time-Dependent Materials》2010,14(2):111-124
A series viscous-elastic-plastic (VEP) indentation model was expanded to include analysis of the common trapezoidal testing
condition, consisting of constant loading—and unloading—rates with an intervening creep hold period. This full VEP model was
applied to analyze nanoindentation test of three polymers and five different types of bone. The full VEP solution allows for
direct determination of the viscous term as calculated from the creep hold, while the elastic and plastic material parameters
were determined from a non-linear curve-fit of the unloading displacement-time data. Additionally, the use of the trapezoidal
loading procedure permitted analysis of the unloading load-displacement data with traditional Oliver-Pharr analysis; the material
properties from this analysis compared well with those obtained with VEP analysis. Using the full VEP solution and fitted
material constants the loading and creep hold displacement-time curves were simulated and matched well to both polymer and
bone experimental data. The full VEP solution shows great promise in for obtaining material parameters for many viscoelastic
materials such as hydrated bone, polymers, and other biological tissues. 相似文献
124.
125.
Effect of Aqueous Extract of the Seaweed Gracilaria domingensis on the Physicochemical,Microbiological, and Textural Features of Fermented Milks
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Adriana Carneiro Tavares Estevam Flávia Carolina Alonso Buriti Tiago Almeida de Oliveira Elainy Virginia dos Santos Pereira Eliane Rolim Florentino Ana Lúcia Figueiredo Porto 《Journal of food science》2016,81(4):C874-C880
The effects of the Gracilaria domingensis seaweed aqueous extract in comparison with gelatin on the physicochemical, microbial, and textural characteristics of fermented milks processed with the mixed culture SAB 440 A, composed of Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium animalis ssp. lactis, were investigated. The addition of G. domingensis aqueous extract did not affect pH, titratable acidity, and microbial viability of fermented milks when compared with the control (with no texture modifier) and the products with added gelatin. Fermented milk with added the seaweed aqueous extract showed firmness, consistency, cohesiveness, and viscosity index at least 10% higher than those observed for the control product (P < 0.05). At 4 h of fermentation, the fermented milks with only G. domingensis extract showed a texture comparable to that observed for products containing only gelatin. At 5 h of fermentation, firmness and consistency increased significantly (P < 0.05) in products with only seaweed extract added, a behavior not observed in products with the full amount of gelatin, probably due to the differences between the interactions of these ingredients with casein during the development of the gel network throughout the acidification of milk. The G. domingensis aqueous extract appears as a promising gelatin alternative to be used as texture modifier in fermented milks and related dairy products. 相似文献
126.
127.
Alessandra Gentili Valeria De Pratti Fulvia Caretti Virginia Pérez-Fernández Pierpaolo Tomai Roberta Curini 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(12):1793-1802
This paper describes a rapid method for confirming residues of thyreostats in meat-based baby foods by using liquid chromatography – dual polarity electrospray – tandem mass spectrometry (LC-ES(±)-MS/MS). Six thioureylenes, belonging to the group of thiouracil and imidazole, were selected for this work: thiouracil (TU), methylthiouracil (MTU), propylthiouracil (PTU), phenylthiouracil (PhTU), mercaptobenzimidazole (MBI) and tapazole (TAP).The amphoteric nature of these compounds allows their electrospray detection in both positive and negative ionisation. Nevertheless, MS detection is not favoured by their low molecular weights, while their chromatographic retention is also thwarted by their high polarity. A pentafluorophenyl (PFP) core-shell phase column was selected to avoid peak asymmetry or peak splitting, and a dual-polarity ionisation method was optimised to obtain a sensitivity as high as possible. The method was validated according to the Commission Decision 657/2002/EC. A simple and fast procedure based on matrix solid phase dispersion (MSPD) was optimised to extract analytes from baby foods with recoveries exceeding 82%. Limit of decision (CCα) and detection capability (CCβ) were lower than the permissible maximum concentration (10 ng g?1). The validated method was then applied to assess the potential occurrence of the six selected thyreostats in nine commercial products. All the samples were found free of contamination. 相似文献
128.
Environmental factors and objectives are formally identified during the scoping stage of environmental impact assessment (EIA) to structure and focus individual assessments. Environmental factors are broad components of the environment, while objectives set the desired outcome for a specific factor. This research assesses the utility of environmental factors and objectives in EIA practice based upon a combination of literature review and interviews with 21 EIA practitioners from Western Australia. Further to providing focus and structure for EIA, practitioners also use environmental factors and objectives for decision-making throughout the process. The majority of practitioners also note that factors and objectives are value adding and useful to their EIA practice. Due to their inherent subjective natures, interviewees noted a lack of consistency regarding how to meet the objectives and challenges in determining the significance of impacts on a factor. Identified opportunities to enhance use of objectives and factors in EIA included provision of more guidance, especially criteria or standards to apply and improve knowledge sharing between EIA stakeholders. 相似文献
129.
Diana Barraza Jiménez Miguel A. Escobedo Bretado Daniel Lardizábal Gutiérrez Jesús M. Salinas Gutiérrez Alejandro López Ortiz Virginia Collins-Martínez 《International Journal of Hydrogen Energy》2013
Hydrogen production through sorption enhanced reforming (SER) use a solid CO2 absorbent to increase hydrogen purity (98%) and to perform reforming and WGS reactions in one single step, thus producing high methane conversions and important energy savings. Na2ZrO3 is as an alternate synthetic CO2 solid absorbent for SER applications. The present research is aimed to establish CO2 sorption kinetics parameters; reaction order, rate constant, apparent, intrinsic and diffusional activation energies. Na2ZrO3 sorption kinetics was studied through TGA as a function of CO2 concentration and temperature. A global reaction rate of first order in CO2 and a strong dependence in temperature was found. The approximate solution to the shrinking core model was used to fit the data. Modeling results indicated the surface reaction as the main resistance to the reaction rate, controlling reaction kinetics with only a minor contribution of the product layer diffusion resistance toward the end of the reaction. 相似文献
130.
In this work, capillary electrophoresis time-of-flight mass spectrometry (CE-TOF-MS) is proposed to identify and quantify the main metabolites in three lines of genetically modified (GM) maize and their corresponding nontransgenic parental lines grown under identical conditions. The shotgun-like approach for metabolomics developed in this work includes optimization of metabolite extraction from GM and non-GM maize, separation by CE, online electrospray-TOF-MS analysis, and data evaluation. A large number of extraction procedures and background electrolytes are tested in order to obtain a highly reproducible and informative metabolomic profile. Thus, using this approach, significant differences were systematically observed between the detected amounts of some metabolites in conventional varieties (Aristis, Tietar, and PR33P66 maize) compared with their corresponding transgenic lines (Aristis Bt, Tietar Bt, and PR33P66 Bt maize). Results point to some of these metabolites as possible biomarkers of transgenic Bt maize, although a larger number of samples needs to be analyzed in order to validate this point. It is concluded that metabolomics procedures based on CE-TOF-MS can open new perspectives in the study of transgenic organisms in order to corroborate (or not) their substantial equivalence with their conventional counterparts. 相似文献