Evaluation of the curvature ductility ratio of a circular cross-section of concrete reinforced with GFRP bars

The present study deals with the use of fiberglass reinforced polymer bars (GFRP) as a replacement for the common steel of a reinforced concrete circular pile, in order to avoid the corrosion of durability of reinforcing bars and thus improve them. The comparative analysis was carried out between a pile reinforced with GFRP and another with steel, where the ductility was evaluated by obtaining moment-curvature diagram. As a result, said idealized moment-curvature diagrams and ductility indices are presented, concluding the ductility of the section reinforced with GFRP in 20% more than that of steel

A Heuristic Computational Model of Basic Cellular Processes and Oxygenation during Spheroid-Dependent Biofabrication

An emerging approach in biofabrication is the creation of 3D tissue constructs through scaffold-free, cell spheroid-only methods. The basic mechanism in this technology is spheroid fusion, which is driven by the minimization of energy, the same biophysical mechanism that governs spheroid formation. However, other factors such as oxygen and metabolite accessibility within spheroids impact on spheroid properties and their ability to form larger-scale structures. The goal of our work is to develop a simulation platform eventually capable of predicting the conditions that minimize metabolism-related cell loss within spheroids. To describe the behavior and dynamic properties of the cells in response to their neighbors and to transient nutrient concentration fields, we developed a hybrid discrete-continuous heuristic model, combining a cellular Potts-type approach with field equations applied to a randomly populated spheroid cross-section of prescribed cell-type constituency. This model allows for the description of: (i) cellular adhesiveness and motility; (ii) interactions with concentration fields, including diffusivity and oxygen consumption; and (iii) concentration-dependent, stochastic cell dynamics, driven by metabolite-dependent cell death. Our model readily captured the basic steps of spheroid-based biofabrication (as specifically dedicated to scaffold-free bioprinting), including intra-spheroid cell sorting (both in 2D and 3D implementations), spheroid defect closure, and inter-spheroid fusion. Moreover, we found that when hypoxia occurring at the core of the spheroid was set to trigger cell death, this was amplified upon spheroid fusion, but could be mitigated by external oxygen supplementation. In conclusion, optimization and further development of scaffold-free bioprinting techniques could benefit from our computational model which is able to simultaneously account for both cellular dynamics and metabolism in constructs obtained by scaffold-free biofabrication

Acculturation and gestational weight gain in a predominantly puerto rican population

Background Identifying risk factors that affect excess weight gain during pregnancy is critical, especially among women who are at a higher risk for obesity. The goal of this study was to determine if acculturation, a possible risk factor, was associated with gestational weight gain in a predominantly Puerto Rican population. Methods We utilized data from Proyecto Buena Salud, a prospective cohort study of Hispanic women in Western Massachusetts, United States. Height, weight and gestational age were abstracted from medical records among participants with full-term pregnancies (n=952). Gestational weight gain was calculated as the difference between delivery and prepregnancy weight. Acculturation (measured via a psychological acculturation scale, generation in the US, place of birth and spoken language preference) was assessed in early pregnancy. Results Adjusting for age, parity, perceived stress, gestational age, and prepregnancy weight, women who had at least one parent born in Puerto Rico/Dominican Republic (PR/DR) and both grandparents born in PR/DR had a significantly higher mean total gestational weight gain (0.9 kg for at least one parent born in PR/DR and 2.2kg for grandparents born in PR/DR) and rate of weight gain (0.03 kg/wk for at least one parent born in PR/DR and 0.06 kg/wk for grandparents born in PR/DR) vs. women who were of PR/DR born. Similarly, women born in the US had significantly higher mean total gestational weight gain (1.0 kg) and rate of weight gain (0.03 kg/wk) vs. women who were PR/ DR born. Spoken language preference and psychological acculturation were not significantly associated with total or rate of pregnancy weight gain. Conclusion We found that psychological acculturation was not associated with gestational weight gain while place of birth and higher generation in the US were significantly associated with higher gestational weight gain. We interpret these findings to suggest the potential importance of the US “obesogenic” environment in influencing unhealthy pregnancy weight gains over specific aspects of psychological acculturation

Dzyaloshinskii-Moriya interactions in valence bond systems

We investigate the effect of Dzyaloshinskii-Moriya interactions on the low temperature magnetic susceptibility for a system whose low energy physics is dominated by short-range valence bonds (singlets). Our general perturbative approach is applied to specific models expected to be in this class, including the Shastry-Sutherland model of the spin-dimer compound SrCu_2(BO_3)_2 and the antiferromagnetic Heisenberg model of the recently discovered S=1/2 kagome compound ZnCu_3(OH)_6Cl_2. The central result is that a short-ranged valence bond phase, when perturbed with Dzyaloshinskii-Moriya interactions, will remain time-reversal symmetric in the absence of a magnetic field but the susceptibility will be nonzero in the T\to 0 limit. Applied to ZnCu_3(OH)_6Cl_2, this model provides an avenue for reconciling experimental results, such as the lack of magnetic order and lack of any sign of a spin gap, with known theoretical facts about the kagome Heisenberg antiferromagnet.Comment: 15 pages, 7 figures; An error in version 2 has been corrected which changes our conclusions (Eq. 8 of version 2 does not apply for systems that do not conserve spin

Acceptance and perception of digital health for managing nutrition in people with Parkinson\u27s disease and their caregivers and their digital competence in the United States: A mixed-methods study

Background and aims: This mixed-methods study examined participants\u27 acceptance and perception of using digital health for managing nutrition and participants\u27 digital competence. The results will be formative for making digital nutrition education more effective and acceptable for people with Parkinson\u27s disease (PwPD) and their informal caregivers. Methods: Qualitative data were collected through in-person semi-structured, dyadic interviews, and questionnaires from 20 dyads (20 PwPD and their caregivers) in the Northeastern United States and analyzed throughout the 2018 to 2019 academic year. Interview transcripts were deductively coded using the framework analysis method. Phrases related to acceptance of digital health were sub-coded into accept, neutral, or reject and those related to perceptions of digital health were sub-coded into perceived usefulness, perceived ease of use, and awareness of digital health. Quantitative data were analyzed using independent samples t tests and Fisher\u27s exact tests. Qualitative codes were transformed into variables and compared to digital competence scores to integrate the data. An average acceptance rate for digital health was calculated through examining the mean percent of phrases coded as accept from interview transcripts. Results: Twenty-five of 40 (62.5%) participants used the internet for at least 5 health-related purposes and the average acceptance rate was 54.4%. Dyads rejected digital health devices if they did not see the added benefit. The majority of participants reported digital health to be useful, but hard to use, and about half felt they needed education about existing digital health platforms. There was no difference in digital competence scores between PwPD and their caregivers (28.6 ± 12.6). Conclusion: Findings suggest that dyads accept and use technology but not to its full potential as technology can be perceived as hard to use. This finding, combined with digital competence scores, revealed that education is warranted prior to providing a digital nutrition intervention

EP-1184: Hypofractionated simultaneous integrated boost radiotherapy after breast-conserving surgery: 3 years follow-up

n/