Activity of metalloproteinases and adiponectin in obese patients— a possible factor of incisional hernias after bariatric procedures

Purpose

Metalloproteinases are a key component of the pathogenesis of abdominal hernias. Obesity is considered a risk factor in herniogenesis and hernia recurrence. The aim of this study was to evaluate the serum concentrations of metalloproteinase-2 (MMP-2), MMP-9, MMP-13, and adiponectin in morbidly obese and nonoverweight controls.

Materials and methods

The participants were recruited from among patients undergoing bariatric and non-bariatric surgery and divided into two groups: I (body mass index (BMI)≥35 kg/m², n=40) and II (BMI<25 kg/m², n=30). Serum concentrations of MMP-2, MMP-9, MMP-13, and adiponectin were measured using enzyme-linked immunosorbent assay (ELISA).

Results

A statistically significant difference between groups was observed for MMP-2 concentration. The median MMP-9 concentration was higher in the obese group, but the difference was not statistically significant. Median MMP-13 concentrations did not differ between groups. Serum adiponectin concentration was insignificantly higher in the non-obese group.

Conclusions

The elevated serum MMP-2 and MMP-9 concentrations in obese individuals may be related to the higher incidence of incisional hernias in this population.

     

Mothers' Perspectives of the Peer-Related Social Development of Young Children with Developmental Delays and Communication Disorders

Mothers' perspectives of children's peer-related social development were obtained from matched groups of young children with developmental delays, communicative disorders, and typically developing children. Structured interviews elicited information on numerous issues including mothers' views of the importance of children's social skills development, rationales with respect to why children succeed or had difficulties on specific social tasks, and the socialization strategies mothers employ to promote children's peer-related social development. Mothers also reported on their efforts to arrange play with peers for their child and the degree to which they monitored that play. Results indicated that mothers rated children's social development as highly important, offered primarily internal rationales (e.g., traits, dispositions) for success or difficulties in achieving social tasks, and endorsed moderate and low power socialization strategies. Differences across the three groups were minimal. Mothers arranged play with peers least often for children with developmental delays and communication disorders, but monitored play more extensively for children with delays. These finding were discussed in terms of mothers adopting a developmental orientation to understand children's social development and their implications for maternal participation in peer competence intervention programs.     

Students’ perceptions of the academic environment and approaches to studying in British postgraduate business education

Recent research on student learning in higher education has identified clear associations between variations in students’ perceptions of the academic environment and variations in their study behaviour. This study investigated a general theoretical model linking students’ demographic characteristics, perceptions and study behaviour with measures of outcome, and in particular, compared three accounts of the causal relationship between perceptions and study behaviour. Data were obtained from 469 postgraduate students at six British business schools. Path analysis was used to assess the causal relationships among the students’ age and gender, their scores on the Course Experience Questionnaire, their scores on the Revised Approaches to Studying Inventory and their ratings of general satisfaction with their programmes. This yielded evidence for the causal efficacy of most of the paths identified in the general theoretical model. In particular, as in the case of students taking more traditional academic subjects, there exists a bidirectional causal relationship between variations in students’ perceptions of the academic environment and variations in their study behaviour.     

The rewarding effects of number and surface area of food in rats

Visual cues have an important role in food preference for both rats and humans. Here, we aim to isolate the effects of numerosity, density, and surface area on food preference and running speed in rats, by using a forced-choice maze paradigm. In Experiment 1, rats preferred and ran faster for a group of multiple smaller pellets rather than a single large pellet, corroborating previous research (Capaldi, Miller, & Alptekin Journal of Experimental Psychology: Animal Behavior Processes, 15(1), 75–80, 1989). Further experiments tested the prevailing hypothesis that multiple food pieces are more reinforcing because they occupy a larger surface area. Experiment 2 controlled for numerosity by utilizing a continuous food: mashed potatoes flattened to cover a larger surface area or rounded into a ball. The rats preferred and ran faster for the flattened potatoes, suggesting surface area plays a role in quantity estimations. Finally, in Experiment 3, rats displayed no preference or difference in running speed between a group of scattered and clustered pellets when number of pellets were kept constant. Taken together, these results suggest that density has an important role in food perception—that is, the rewarding effect of higher numerosity or larger surface area is removed when the food does not fill out the entire space. Alternative explanations and implications for human diet are discussed.     

Fighting for Desired Versions of a Future Self: How Young Women Negotiated STEM-Related Identities in the Discursive Landscape of Educational Opportunity

In this article, we investigate how the national imperative to increase opportunities for young women of color in science, technology, engineering, and mathematics (STEM) and to broaden their participation was taken up locally at two high schools in one school district. Using ethnographic and longitudinal data, we focus on four young women of color (two at each school) as they negotiated STEM-related identities in the discursive and practice contexts of their lives at school. Using Holland and Lave’s concept of history in person, we view the young women as fighting for particular versions of a future self while entangled in discursive and social relations that threatened to position them differently than they wished to be. We find that their fight for future selves was not—for them—with the national narrative about women of color in STEM but with local school narratives that negatively positioned students of color more broadly and remained silent on issues of gender, the intersection of gender and race, and the implications for STEM. High school success in STEM came as a hopeful but potentially fragile byproduct of struggles to differentiate themselves from people like them (other Blacks, Latinas, the poor). Implications of these findings are discussed.     

The Future of Student Self-Assessment: a Review of Known Unknowns and Potential Directions

Educational Psychology Review - This paper reviews current known issues in student self-assessment (SSA) and identifies five topics that need further research: (1) SSA typologies, (2) accuracy, (3)...     

Large amplitude free vibration of a flexible panel coupled with a leaking cavity

This paper addresses the effect of leakage on the natural frequencies of a large amplitude vibrating panel backed by a cavity, which has not been considered in many other related studies. The structural-acoustic governing equations are employed to study this nonlinear problem. An elliptical integral method, which was recently developed for the nonlinear panel cavity problem, is introduced here to solve for the structural-acoustics responses. The present results agree reasonably well with those obtained from the classical harmonic balance method. Modal convergences of the nonlinear solutions are performed to verify the proposed method. The effects of vibration amplitude and leakage size are studied and discussed. It is found that (1) the edge leakages in a panel cavity system significantly affect the natural frequency properties, and (2) the edge leakages induce a low frequency acoustic resonance.