Developmental phases in self-regulation: Shifting from process goals to outcome goals.

The effects of goal setting and self-monitoring during self-regulated practice on the acquisition of a complex motoric skill were studied with 90 high school girls. It was hypothesized that girls who shifted goals developmentally from process to outcome goals would surpass classmates who adhered to only process goals who, in turn, would exceed classmates who used only outcome goals in posttest dart-throwing skill, self-reactions, self-efficacy perceptions, and intrinsic interest in the game. Support for all hypotheses derived from the developmental model was found. The girls' self-reactions to dart-throwing outcomes and self-efficacy perceptions about dart skill were highly correlated with their intrinsic interest in the game. It was also found that self-recording, a formal form of self-monitoring, enhanced dart-throwing skill, self-efficacy, and self-reaction beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A model for European Biogenic Volatile Organic Compound emissions: Software development and first validation

A grid-oriented Biogenic Emission Model (BEM) has been developed to calculate Non-Methane Volatile Organic Compound (NMVOC) emissions from vegetation in high spatial and temporal resolutions. The model allows the emissions calculation for any modeling domain covering Europe on the basis of: 1) the U.S. Geological Survey 1-km resolution land-use database, 2) a land-use specific, monthly isoprene, monoterpene and Other Volatile Organic Compound (OVOC) emission potentials and foliar biomass densities database, 3) temperature and solar radiation data provided by the mesoscale meteorological model MM5. The model was applied for Europe in 30-km spatial resolution for the year 2003. The European total emissions for 2003 consist of 33.0% isoprene, 25.5% monoterpenes and 41.5% OVOC. BEM results are compared with those from the well-documented global Model of Emissions of Gases and Aerosols from Nature (MEGAN). The BEM total emissions compare well with the MEGAN ones. In July 2003, the results of both models agree within a factor of 1.2 for total isoprene emissions and within a factor of 2 for total monoterpene emissions. The comparison of the spatial distributions of the July 2003 isoprene and monoterpene emissions calculated with BEM and MEGAN shows that, in the greater part of the study area, the differences are below the current uncertainty limit for the estimation of spatially-resolved biogenic VOC emissions in Europe being equal to about ±600 kg km^?2 month^?1. Differences that are above this limit are found mainly in the eastern European countries for isoprene and in the Mediterranean countries for monoterpenes.     

Enhancing Fluorescence LC Analysis of Biogenic Amines in Fish Tissues by Precolumn Derivatization with Naphthalene-2,3-dicarboxaldehyde

This work reports a sensitive high-pressure liquid chromatography method for the simultaneous determination of biogenic mono- and diamines in fish tissues. Highly fluorescent derivatives of the amines were obtained by precolumn derivatization with naphthalene-2,3-dicarboxaldehyde, in the presence of cyanide ion as the nucleophile and of heptylamine as the internal standard. The chromatographic separation was performed using a mobile phase of acetonitrile/methanol/10 % (v/v) acetone in water, delivered in gradient mode on an Inertsil ODS-3 column (250?×?4 mm i.d., 5 μm). The method was successfully applied to the analysis of fresh and canned tuna fish tissues, subjected to ultrasound-assisted liquid–liquid extraction. The variables affecting the derivatization yield as well as the extraction recovery of the analytes from the sample matrix were investigated. Results were quantified against the internal standard, according to the matrix-matched approach. Limits of detection between 2.5 and 330 mg kg^?1 sample were achieved. The precision and accuracy of assay in samples was satisfactory, yielding relative standard deviation and recovery values between 0.3 and 4.2 % and 81.0 and 102.5 %, respectively.     

Elongational flow studies of set yogurt

Three series of prepared set yogurt samples were tested using squeezing flow viscometry. Samples were compressed using an Instron UTM at constant deformation rate. The first series containing added caseinates exhibited deformation behaviour of a gel. Firmness was dependent on caseinate concentration. The second series contained skimmed milk powder. Their behaviour was more that of a colloidal dispersion at low added powder content and of a gel at higher added amounts. The third series contained carrageenan salts. Their behaviour was that of a dispersion irrespective of the carrageenan concentration. The consistency of the samples examined was evaluated using plots of stress growth coefficients as function of biaxial strain rate. The results indicated that the technique could be used to distinguish changes in yogurt structure caused by the addition of various additives at various concentration levels, to milk to enhance yogurt consistency.     

Effect of increased wind penetration on system prices in Korea's electricity markets

In this paper, we examine the effect of increased wind penetration on system marginal prices (SMPs) in South Korea's electricity market. Korea's renewable portfolio standard (RPS) went into effect in 2012, with a goal of increasing the share of renewable generation to 10% of the total load by 2022. We examine the output of wind installations across the Korean peninsula and simulate an increase in wind penetration consistent with Korea's RPS targets. Under a variety of assumptions on demand elasticity, we find that higher shares of wind generation in total supply reduce both the average SMP and its variation. In particular, we find that wind energy output on the Korean peninsula is more correlated with peak electricity demand than has been reported for other regions. The per‐unit value of wind energy to owners of wind assets is thus higher for South Korea than would be the case for European or North American locations with a similar mix of fuels other than wind. Copyright © 2013 John Wiley & Sons, Ltd.     

Effect of low-dose radiation on microbiological, chemical, and sensory characteristics of chicken meat stored aerobically at 4 degrees C

The effect of gamma-radiation (0.5, 1, and 2 kGy) on the shelf life of fresh skinless chicken breast fillets stored aerobically at 4 degrees C was evaluated. Microbiological, chemical, and sensorial changes occurring in chicken samples were monitored for 21 days. Irradiation reduced populations of bacteria, i.e., total viable bacteria, Brochothrix thermosphacta, lactic acid bacteria (LAB), and the effect was more pronounced at the highest dose (2 kGy). Pseudomonads, yeasts and molds, and Enterobacteriaceae were highly sensitive to gamma-radiation and were completely eliminated at all doses. Of the chemical indicators of spoilage, thiobarbituric values for nonirradiated and irradiated aerobically packaged chicken samples were in general low (<1 mg of malonaldehyde per kg of muscle) during refrigerated storage for 21 days. With regard to volatile amines, both trimethylamine nitrogen (TMA-N) and total volatile basic nitrogen (TVB-N) values for nonirradiated aerobically packaged chicken increased steeply, with final values of ca. 20.3 and 58.5 mg N/100 g of muscle, respectively. Irradiated aerobically packaged chicken samples had significantly lower TMA-N and TVB-N values (P < 0.05) of ca. 2.2 to 3.6 and 30.5 to 37.1 mg N/100 g of muscle, respectively, during refrigerated storage for 21 days. Of the biogenic amines monitored, only putrescine and cadaverine were detected in significant concentrations in both nonirradiated and irradiated chicken samples, whereas histamine formation was noted only in nonirradiated samples throughout storage. On the basis of sensorial evaluation, low-dose irradiation (0.5 and 1.0 kGy) in combination with aerobic packaging extended the shelf life of fresh chicken fillets by ca. 4 to 5 days, whereas irradiation at 2.0 kGy extended the shelf life by more than 15 days compared with that of nonirradiated chicken.     

Determination of organic compounds in bottled waters

The presence of organic compounds in bottled waters available in the Greek market and their fate when the representative samples exposed at different conditions were the main purposes of this study. The determination of the organic compounds was performed by gas chromatography–mass spectrometry techniques. Disinfection by-products compounds, such as trihalomethanes (THMs) and haloacetic acids (HAAs), were detected at low concentrations in bottled waters. As far as it concerns other organic substances, Greek bottled drinking waters did not contain volatile organic compounds (VOCs), and carbonyl compounds as well as other carcinogen and hormone disrupter phthalates were not identified, except for the plasticiser phthalate, diethylhexyl phthalate (DEHP). Moreover, samples contained other organic chemicals, whose identity has not yet been confirmed. The behavior of organic compounds was influenced by parameters such as conditions of storage, type of water. Finally, a comparison has been performed between the analysis of bottled and local tap waters.     

Effect of microwave heating on the migration of dioctyl adipate and acetyltributyl citrate plasticizers from food grade PVC and PVDC/PVC films into ground meat

 Migration of dioctyl adipate (DOA) and acetyltributyl citrate (ATBC) plasticizers from plasticized poly(vinyl chloride) and poly(vinylidene chloride/vinyl chloride) films into ground meat of varying fat content (3%, 12%, 30%, 55%) during microwave heating has been studied. The plasticizer migrating into ground meat was determined using an indirect gas chromatographic method after saponification of the ester-type plasticizer (DOA or ATBC) and subsequent collection of the alcohol component of the ester, namely 2-ethyl-1-hexanol and 1-butanol, respectively. Identical unwrapped microwave heated (control) samples were also analysed for DOA and ATBC content. Migration was dependent on heating time, fat content of the meat and the initial concentration of the plasticizer in the film. Migration of DOA and ATBC into ground meat did not reach equilibrium after heating for 4 min at full power even for meat samples of high fat content (55%). Migration values of DOA and ATBC into ground meat of 55% fat content after 4 min of heating in a microwave oven were 172.39 mg/kg (14.62 mg/dm²) and 17.24 mg/kg (0.62 mg/dm²), respectively. Migration into control samples was below the detection limit of the method employed (<2 mg/kg for DOA and <2.5 mg/kg for ATBC).