“How am I supposed to feel?”: Social Support and Black Mothers’ Infant Feeding Decisions

Background: Many of the adverse health outcomes that breastfeeding protects against disparately affect black mothers and children; however, black mothers are the least likely racial group in the U.S. to breastfeed. Black mothers have indicated that breastfeeding barriers include a lack of social support. Qualitative studies examining such breastfeeding barriers often focus on women who have unsuccessfully breastfed and fail to define the experiences of women who have successfully breastfed. This study aims to identify the impacts of social support on the infant feeding decisions of black women with varying levels of breastfeeding success. Methods: Twenty-five black women were interviewed in mini-focus groups and were recruited according to three categorizations of breastfeeding duration: formula-fed only, breastfed for ≤3 months, or breastfed for ≥4 months. Focus group questions addressed mothers’ perceptions, attitudes, intentions, experiences, and perceived barriers and facilitators regarding infant feeding practices. Group interviews were audio-recorded, transcribed, and then analyzed specific to social support using a grounded theory approach. Results: Mothers in all three breastfeeding categorizations reported experiences with tangible, emotional, and informational support from members across sectors of their social networks. Additionally, mothers reported dissonance between informational support received and their personal infant feeding intentions as well as a need for increased social support regardless of infant feeding method. Conclusions: This study provides an in-depth analysis of social support as a facilitator and barrier to infant feeding decisions for black mothers. Given the findings, it is suspected that experiences with social support are integral to women’s infant feeding decisions.https://scholarscompass.vcu.edu/gradposters/1083/thumbnail.jp

Liquid-state theory of charged colloids

A simple theory of the fluid state of a charged colloidal suspension is proposed. The full free energy of a polyelectrolyte solution is calculated. It is found that the counterions condense onto the polyions forming clusters composed of one polyion and n counterions. The distribution of cluster sizes is determined explicitly. In agreement with the current experimental and Monte Carlo results, no liquid-gas phase separation was encountered.Comment: 4 pages, 2 Postscript figures, uses multicol.sty; changed conten

AM-OER: An Agile Method for the Development of Open Educational Resources

Open Educational Resources have emerged as important elements of education in the contemporary society, promoting life-long and personalized learning that transcends social, eco- nomic and geographical barriers. To achieve the potential of OERs and bring impact on education, it is necessary to increase their development and supply. However, one of the current challenges is how to produce quality and relevant OERs to be reused and adapted to different contexts and learning situations. In this paper we proposed an agile method for the development of OERs – AM-OER, grounded on agile practices from Software Engineering. Learning Design practices from the OULDI project (UK Open University) are also embedded into the AM-OER aiming at improving quality and facilitating reuse and adaptation of OERs. In order to validate AM-OER, an experiment was conducted by applying it in the development of an OER on software testing. The results showed preliminary evidences on the applicability, effectiveness and ef ciency of the method in the development of OERs

Using Text Similarity to Detect Social Interactions not Captured by Formal Reply Mechanisms

In modeling social interaction online, it is important to understand when people are reacting to each other. Many systems have explicit indicators of replies, such as threading in discussion forums or replies and retweets in Twitter. However, it is likely these explicit indicators capture only part of people's reactions to each other, thus, computational social science approaches that use them to infer relationships or influence are likely to miss the mark. This paper explores the problem of detecting non-explicit responses, presenting a new approach that uses tf-idf similarity between a user's own tweets and recent tweets by people they follow. Based on a month's worth of posting data from 449 ego networks in Twitter, this method demonstrates that it is likely that at least 11% of reactions are not captured by the explicit reply and retweet mechanisms. Further, these uncaptured reactions are not evenly distributed between users: some users, who create replies and retweets without using the official interface mechanisms, are much more responsive to followees than they appear. This suggests that detecting non-explicit responses is an important consideration in mitigating biases and building more accurate models when using these markers to study social interaction and information diffusion.Comment: A final version of this work was published in the 2015 IEEE 11th International Conference on e-Science (e-Science

Donnan equilibrium and the osmotic pressure of charged colloidal lattices

We consider a system composed of a monodisperse charge-stabilized colloidal suspension in the presence of monovalent salt, separated from the pure electrolyte by a semipermeable membrane, which allows the crossing of solvent, counterions, and salt particles, but prevents the passage of polyions. The colloidal suspension, that is in a crystalline phase, is considered using a spherical Wigner-Seitz cell. After the Donnan equilibrium is achieved, there will be a difference in pressure between the two sides of the membrane. Using the functional density theory, we obtained the expression for the osmotic pressure as a function of the concentration of added salt, the colloidal volume fraction, and the size and charge of the colloidal particles. The results are compared with the experimental measurements for ordered polystyrene lattices of two different particle sizes over a range of ionic strengths and colloidal volume fractions.Comment: 8 pages, 4 Postscript figures, uses multicol.sty, to be published in European Physical Journal

On the r−r-stability of spacelike hypersurfaces

In this paper we study the strong stability of spacelike hypersurfaces with constant $r$-th mean curvature in Generalized Robertson-Walker spacetimes of constant sectional curvature. In particular, we treat the case in which the ambient spacetime is the de Sitter space