Lipid peroxidation of fish oils

Fish and fish oils are the richest sources of ω-3 fatty acids. However, they are susceptible to lipid peroxidation due to their high degree of unsaturation. In the present study, the level of thiobarbituric acid reactive material in various fish oils available in the market with and without added Vitamin E was determined. The peroxide levels in fish oil heated to food frying temperature of 180°C and the effect of addition of vitamin E has also been studied. The results indicate that the peroxide levels in almost all the products available in the market were abnormally high irrespective of their Vitamin E content. This might be due to the inefficient methods used for processing and storage of fish oils. Addition of vitamin E was found to have a significant effect in lowering the rate of peroxidation of fish oil during thermal stress, showing that association of antioxidants with ω-3 fatty acids lowers the rate of lipid peroxidation.     

“Some explanation here”: a case study of learning opportunities and tensions in an informal science learning environment

Recent scholarship highlights the wealth of varied and interconnected opportunities for learning science that informal environments can provide; yet, participants with different experiences, knowledge, and backgrounds do not all learn in the same ways. Thus, studies are needed that examine how particular participants take up learning opportunities (LOs) in informal contexts. In this ethnographic case study, we focus on the learning experiences of one fifth-grade girl, Nina, who reported that she was not able to learn as much as she had hoped from her participation in an afterschool robotics engineering club. Through analysis of video-recordings, interviews, and field notes, we investigated how instructors and peers shaped LOs for Nina and the environmental tensions that affected how LOs were shaped and how Nina took them up. Comparison of examples in which instructor and peer-afforded LOs were realized and unrealized (i.e., presented in ways that Nina could take them up or not) illuminates multiple tensions. Club members faced tensions related to differing goals and abilities to teach each other, while the instructors faced tensions related to their roles in informal learning environments and their propensity to direct participants to other resources. As a result, many potential LOs for Nina in this rich inquiry learning environment where unrealized because instructors and peers did not shape them in ways that were explicit, elaborated upon, or connected to Nina’s prior knowledge, and because Nina was not necessarily attuned to potential LOs in the informal context. We conclude with implications for instructors in informal learning environments.     

Executive functions as predictors of math learning disabilities

In the past years, an increasing number of studies have investigated executive functions as predictors of individual differences in mathematical abilities. The present longitudinal study was designed to investigate whether the executive functions shifting, inhibition, and working memory differ between low achieving and typically achieving children and whether these executive functions can be seen as precursors to math learning disabilities in children. Furthermore, the predictive value of working memory ability compared to preparatory mathematical abilities was examined. Two classifications were made based on (persistent) mathematical ability in first and second grade. Repeated measures analyses and discriminant analyses were used to investigate which functions predicted group membership best. Group differences in performance were found on one inhibition and three working memory tasks. The working memory tasks predicted math learning disabilities, even over and above the predictive value of preparatory mathematical abilities.     

Traumatic and stressful events in early childhood: can treatment help those at highest risk?

Objective

This study involves a reanalysis of data from a randomized controlled trial to examine whether child-parent psychotherapy (CPP), an empirically based treatment focusing on the parent-child relationship as the vehicle for child improvement, is efficacious for children who experienced multiple traumatic and stressful life events (TSEs).

Methods

Participants comprised 75 preschool-aged children and their mothers referred to treatment following the child's exposure to domestic violence. Dyads were randomly assigned to CPP or to a comparison group that received monthly case management plus referrals to community services and were assessed at intake, posttest, and 6-month follow-up. Treatment effectiveness was examined by level of child TSE risk exposure (<4 risks versus 4+ TSEs).

Results

For children in the 4+ risk group, those who received CPP showed significantly greater improvements in PTSD and depression symptoms, PTSD diagnosis, number of co-occurring diagnoses, and behavior problems compared to those in the comparison group. CPP children with <4 risks showed greater improvements in symptoms of PTSD than those in the comparison group. Mothers of children with 4+ TSEs in the CPP group showed greater reductions in symptoms of PTSD and depression than those randomized to the comparison condition. Analyses of 6-month follow-up data suggest improvements were maintained for the high risk group.

Conclusions

The data provide evidence that CPP is effective in improving outcomes for children who experienced four or more TSEs and had positive effects for their mothers as well.

Practice implications

Numerous studies show that exposure to childhood trauma and adversity has negative consequences for later physical and mental health, but few interventions have been specifically evaluated to determine their effectiveness for children who experienced multiple TSEs. The findings suggest that including the parent as an integral participant in the child's treatment may be particularly effective in the treatment of young children exposed to multiple risks.     

Directionality effects in simultaneous language interpreting: the case of sign language interpreters in The Netherlands

The quality of interpretations produced by sign language interpreters was investigated. Twenty-five experienced interpreters were instructed to interpret narratives from (a) spoken Dutch to Sign Language of The Netherlands (SLN), (b) spoken Dutch to Sign Supported Dutch (SSD), and (c) SLN to spoken Dutch. The quality of the interpreted narratives was assessed by 5 certified sign language interpreters who did not participate in the study. Two measures were used to assess interpreting quality: the propositional accuracy of the interpreters' interpretations and a subjective quality measure. The results showed that the interpreted narratives in the SLN-to-Dutch interpreting direction were of lower quality (on both measures) than the interpreted narratives in the Dutch-to-SLN and Dutch-to-SSD directions. Furthermore, interpreters who had begun acquiring SLN when they entered the interpreter training program performed as well in all 3 interpreting directions as interpreters who had acquired SLN from birth.     

Looking for students’ personal characteristics predicting study outcome

The central goal of this study is to clarify to what degree former education and students’ personal characteristics (the ‘Big Five personality characteristics’, personal orientations on learning and students’ study approach) may predict study outcome (required credits and study continuance). Analysis of the data gathered through questionnaires of 1,471 Universities of Applied Sciences students make clear that former Education did not come forth as a powerful predictor for Credits or Study Continuance. Significant predictors are Conscientiousness and Ambivalence and Lack of Regulation. The higher the scores on Conscientiousness the more credits students are bound to obtain and the more likely they will continue their education. On the other hand students with high scores on Ambivalence and Lack of Regulation will most likely obtain fewer Credits or drop out more easily. The question arises what these results mean for the present knowledge economy which demands an increase of inhabitants with an advanced level of education. Finally, implications and recommendations for future research are suggested.     

Effects of nonmaternal care in the first 3 years on children's academic skills and behavioral functioning in childhood and early adolescence: a sibling comparison study

Nonmaternal care of infant children is increasingly common, but there is disagreement as to whether it is harmful for children. Using data from 9,185 children (5 years and older) who participated in the Children of the National Longitudinal Survey of Youth, the current study compared 2 groups: those for whom nonmaternal care was initiated in the first 3 years and those for whom it was not. Between-family comparisons showed that early nonmaternal care was associated with higher achievement and lower behavior problem scores in childhood and adolescence. However, within-family comparisons failed to detect differences between siblings who had different early nonmaternal care experiences. The study concludes that the timing of entry to nonmaternal care in the first 3 years has neither positive nor negative effects on children's outcomes.     

Beliefs about Genes and Environment as Determinants of Behavioral Characteristics

This study investigates beliefs about the determinants of suchbehavioral characteristics as intelligence, athleticism, obesity,and alcoholism by asking respondents to the 2004 General SocialSurvey to rate vignettes describing individuals exhibiting thesecharacteristics along a 21-point scale ranging from completegenetic determination to complete environmental determination.The vignettes systematically varied the social desirabilityof the characteristic as well as the race and gender of theperson exhibiting it. We analyzed the effect of the carefullycounterbalanced vignette characteristics and the correspondingrater characteristics on respondents’ ratings of the vignettes,hypothesizing that these ratings would reflect mechanisms ofclaiming credit for desirable characteristics and avoiding blamefor undesirable ones. Contrary to our expectations, we foundno effect of any of the vignette characteristics on the ratings,and only two significant main effects of respondent demographiccharacteristics: Black respondents were more likely to use geneticratings; and better educated respondents, environmental ones. Received for publication October 26, 2006. Accepted for publication April 23, 2007.     

Pigeons’ memory for sequences of light flashes when gap duration is an unreliable discriminative cue

In Experiment 1, pigeons were trained with a 1-sec dark and a 1-sec houselight-illuminated delay interval to discriminate between sequences of two and four flashes of light (feeder illumination). The sequences could be discriminated on the basis of the number of flashes, the number of gaps, or the duration of the gap between flashes. A choose-few bias was obtained at extended dark delays, but not at extended illuminated delays. Pigeons appeared to confuse long dark delays with the longer gap between flashes on few-sample trials. In Experiment 2, additional sample sequences were included that made gap duration an unreliable cue for discriminating between the few and many samples. A significant choose-many bias was obtained at extended dark delay intervals, but no biased forgetting was found at extended illuminated delays. The pigeons appeared to discriminate light flash sequences by relying on multiple temporal features of a sequence rather than using an event switch to count flashes. The biased-forgetting effects observed appear to be due to instructional ambiguity that results from the similarity of the delay interval to features of the flash sequences. nt]mis|This research was supported by Grant OGPOOD6378 from the Natural Sciences and Engineering Research Council of Canada to A.S.