Assessment of oxidative stress and effect of antioxidant supplementation during radiotherapy in carcinoma of upper digestive tract

Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity, pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing the desirable therapeutic effect of radiotherapy.     

Reaction to videocolposcopy in the assessment of child sexual abuse.

OBJECTIVE: The purpose of this study was to clinically assess children's reactions to videocolposcopy with real-time observation of magnified anogenital images (VCO), and to evaluate whether these reactions are affected by patient or other characteristics such as response to preparation, disclosure of child sexual abuse (CSA), or examination findings. METHOD: Consecutive cases of children ages less than 18 years referred to a children's hospital clinic for nonemergent evaluation of suspected CSA during 1997 through 1999 were studied. We noted the child's response with clinical observation before and after videocolposcopy, and used the Genital Examination Distress Scale (GEDS) after evaluation. We compared these responses to patient gender, age, ethnicity, pubertal status, disclosure of child sexual abuse (CSA), and physical examination findings using univariate and regression analyses. RESULTS: Two hundred twenty-seven children (mean age 7.2 years, range 0-17) underwent videocolposcopy, of whom 55.1% disclosed sexual abuse and 17.2% had a positive examination. More than 80% were female, prepubertal, and non-Hispanic White. Most (85%) watched their examination on the monitor and were either cooperative or enthusiastic before and after videocolposcopy. Fewer very young children (ages 0-3 years) or female adolescents (13-17 years) watched the monitor. Summed GEDS scores were strongly correlated with observed responses after the procedure (p = .01), and children with CSA disclosure were three times more likely to watch the monitor and five times more likely than those without disclosure to have improved comfort. Other patient characteristics were not significantly associated with patient reaction to VCO. CONCLUSIONS: Most children are interested in watching their anogenital examination using magnified real-time images obtained during videocolposcopy and tolerate the procedure well. The GEDS is highly correlated with subjective clinical observation. While some children may particularly benefit from participating in their examination by using VCO, long-term effects of the evaluation and any relationship of a child's reaction to videocolposcopy with their history of sexual victimization remain to be established.     

The Effects of Gender Interaction Patterns on Student Participation in Computer-Supported Collaborative Argumentation

In this study we examined response patterns in exchanges between males and females and their effects on gender participation in five online debates. Students classified messages into arguments, evidence, critiques, and elaborations while posting messages to the debates to facilitate argumentation and the sequential analysis of message-response sequences. The findings revealed no differences in number of critiques posted in response to arguments because females were just as likely as males to critique messages from both males and females, and because females responded to males with critiques at a higher than expected frequency. Posthoc analysis revealed strong indications that females posted fewer rebuttals to the critiques of females than males, and males posted more rebuttals to the critiques of females than females. The methods used in this study illustrate a process-oriented approach to explain and predict gender differences in participation and serve as a framework for future research on gender participation, group interaction, and strategies for facilitating collaborative argumentation and problem solving.     

Learning design and learning analytics in mobile and ubiquitous learning: A systematic review

Mobile and Ubiquitous Learning (m/u-learning) are finding an increasing adoption in education. They are often distinguished by hybrid learning environments that encompass elements of formal and informal learning, in activities that happen in distributed settings (indoors and outdoors), across physical and virtual spaces. Despite their purported benefits, these environments imply additional complexity in the design, monitoring and evaluation of learning activities. The research literature on learning design (LD) and learning analytics (LA) has started to deal with these issues. This paper presents a systematic literature review of LD and LA, in m/u-learning. Apart from providing an overview of the current research in the field, this review elicits elements of common ground between both communities, as shown by the similar learning contexts and complementary research contributions, and based on the research gaps, proposes to: address m/u-learning beyond higher education settings, reinforce the connection between physical and virtual learning spaces, and more systematically align LD and LA processes.     

Impacts of an Early Childhood Mathematics and Science Intervention on Teaching Practices and Child Outcomes

abstract

This randomized controlled trial examined effects of the MyTeachingPartner-Math/Science intervention on the quality and quantity of teachers’ mathematics and science instruction, and children’s mathematics and science outcomes in 140 pre-kindergarten classrooms. Teachers participated in the intervention for two years with consecutive cohorts of children. Results from Year 1 are considered experimental, however due to high levels of attrition, results from Year 2 are considered quasi-experimental. Across both years, intervention teachers exhibited higher quality and quantity of instruction. In Year 1, there were no significant effects of the intervention on children’s outcomes. In Year 2, children in intervention classrooms made greater gains in teachers’ ratings of mathematics and science skills and performed better on a spring assessment of science skills. These results have implications for designing and evaluating professional development aimed at supporting children’s mathematics and science knowledge and skills.     

Variability in children’s early reading strategies

The present study examines the development of sight word reading in young children by examining changes in their self‐reported reading strategies over time. A sample of 65 five to seven year olds were asked to read 40 real word items, all carefully matched for letter length and word frequency, on three separate occasions. Changes in the children’s word identifications were measured using immediately retrospective verbal self‐reports. Overall, the results showed some variability in the children’s self‐reported reading strategies. Over time the children relied less on phonological strategies and moved towards reliance on directly retrieving words from memory. This change was most evident in the older children; while both year groups showed similar patterns of shifting reliance from explicit phonological strategies to retrieval, this shift was simply less frequent among the younger children. An analysis of word‐specific changes in reading strategies showed that the older children had a better sight vocabulary for more complex word items. These findings provide further support for Ehri’s mediated phase theory in explaining children’s development in learning to read.