Finite Element Modeling of Axially Loaded CFRP-Confined Rectangular Reinforced Concrete Columns

This paper investigates numerically the behaviour of rectangular RC columns strengthened with carbon fiber reinforced polymer (CFRP) composites under uniaxial loading. For this a reason, a parametric study is conducted and the effects of CFRP layers number, compressive strength of unconfined concrete, and fiber orientation on the behaviour of such columns have been studied. The number of CFRP layers has been changed from one to five layers while the fibers are oriented transversely. Compressive strength of unconfined concrete has been increased from 26 MPa to 45 MPa. In addition, three different fiber orientations are considered. The results show that an increase in the number of CFRP layers would enhance the ultimate strength of specimens. Although increasing the number of layers would not increase the ultimate strength of specimens exponentially, but the rate of strength gain would also decrease. Moreover, it is shown that lateral strains increase as the layer number increases. The effect of unconfined concrete strength on the ultimate strength is less for low strength concrete than high strength concrete. Evaluating the effect of fiber orientation shows that the maximum ultimate strength is obtained from transverse orientation and as the angle of orientation increases, the ultimate strength decreases

Diffusion in Networks and the Unexpected Virtue of Burstiness

Whether an idea, information, infection, or innovation diffuses throughout a society depends not only on the structure of the network of interactions, but also on the timing of those interactions. Recent studies have shown that diffusion can fail on a network in which people are only active in "bursts", active for a while and then silent for a while, but diffusion could succeed on the same network if people were active in a more random Poisson manner. Those studies generally consider models in which nodes are active according to the same random timing process and then ask which timing is optimal. In reality, people differ widely in their activity patterns -- some are bursty and others are not. Here we show that, if people differ in their activity patterns, bursty behavior does not always hurt the diffusion, and in fact having some (but not all) of the population be bursty significantly helps diffusion. We prove that maximizing diffusion requires heterogeneous activity patterns across agents, and the overall maximizing pattern of agents' activity times does not involve any Poisson behavior

Dynamic Matching Market Design

We introduce a simple benchmark model of dynamic matching in networked markets, where agents arrive and depart stochastically and the network of acceptable transactions among agents forms a random graph. We analyze our model from three perspectives: waiting, optimization, and information. The main insight of our analysis is that waiting to thicken the market can be substantially more important than increasing the speed of transactions, and this is quite robust to the presence of waiting costs. From an optimization perspective, naive local algorithms, that choose the right time to match agents but do not exploit global network structure, can perform very close to optimal algorithms. From an information perspective, algorithms that employ even partial information on agents' departure times perform substantially better than those that lack such information. To elicit agents' departure times, we design an incentive-compatible continuous-time dynamic mechanism without transfers

Critical Pedagogy in an EFL Context: Towards Solving the Definition Precision Problem

Some critics mention the definition variety problem, or a lack of definitional precision, as a major problem with Critical Pedagogy (CP). One who has just been familiar with CP may not have enough information regarding its roots and its multidisciplinary nature. S/he may not know about the historical development of CP and thus may not even be acquainted with the possibility of the existence of different definitions and versions for CP. Therefore, a newly-arrived researcher may get confused encountering the different definitions of CP. On the other hand, the literature on CP does not seem to be directed at the new researchers. By having five phases, the present mixed-methods study offered a simple definition of CP encompassing all the common grounds in the literature using an extensive literature review, the Grounded Theory approach, and Factor Analysis. Ten Iranian EFL professionals in CP, besides 306 Iranian EFL teachers, participated in the present work. The results of the present work may be helpful in developing CP-based curricula and courses which look into the real needs of the learners and teachers in order to have a more fruitful educational system

Critical Pedagogy in an EFL Context: Towards Solving the Definition Precision Problem

Some critics mention the definition variety problem, or a lack of definitional precision, as a major problem with Critical Pedagogy (CP). One who has just been familiar with CP may not have enough information regarding its roots and its multidisciplinary nature. S/he may not know about the historical development of CP and thus may not even be acquainted with the possibility of the existence of different definitions and versions for CP. Therefore, a newly-arrived researcher may get confused encountering the different definitions of CP. On the other hand, the literature on CP does not seem to be directed at the new researchers. By having five phases, the present mixed-methods study offered a simple definition of CP encompassing all the common grounds in the literature using an extensive literature review, the Grounded Theory approach, and Factor Analysis. Ten Iranian EFL professionals in CP, besides 306 Iranian EFL teachers, participated in the present work. The results of the present work may be helpful in developing CP-based curricula and courses which look into the real needs of the learners and teachers in order to have a more fruitful educational system

Evaluation of photon, proton, helium, and carbon ion irradiation in prototypic NSCLC and HNSCC preclinical xenograft models

This thesis combines the use of novel radiation qualities with in-vivo functional genetic screens in prototypic head and neck squamous cell carcinoma (HNSCC, FaDu) and non-small cell lung cancer (NSCLC, A549) preclinical xenograft models. Using whole-genome FaDu and A549 CRISPR/Cas9 libraries, in-vivo tumor response to conventional photon radiotherapy as well as a series of particles with gradually enhanced ionization density (LET), i.e., proton, helium, carbon- and oxygen ion irradiation were investigated. Two genome wide - GeCKO A and Brunello – gRNA libraries were integrated in Cas9 expressing FaDu and A549 cells. Transcriptome and guide representation studies using next-generation sequencing (NGS) and quantitative analysis provided insights into the tumor evolutionary landscape and genes/pathways contributing to tumor fitness under different in-vivo and therapeutic selection pressures. A pronounced reduction of library complexity was detected in-vivo vs in-vitro, regardless of tumor model and library. Additional reduction was observed in irradiated samples. Clonal tumor evolution could be recapitulated, as outgrown tumors showed an expansion of few clones constituting the majority of the tumors. Tumor growth rate was negatively linked to library complexity – a potential surrogate for intratumoral heterogeneity – strengthening the previously described association between high intratumoral complexity and increased tumor aggressiveness. High-LET irradiation showed improved capacity for cell killing, with either tumor regression (in FaDu model) or enhanced growth delay (in A549 model). Irradiation type specific transcriptome fingerprints revealed both favorable- and non-favorable changes, comprising modulation of the tumor microenvironment (TGF-β), inflammation and senescence, pro- and anti-angiogenic alterations, DNA damage repair, hypoxia and antigen presentation. Main factors influencing transcriptome profiles differences within particles were LET (high vs. low LET groups). On guide level, radio-resistance seems to be mediated by loss of TGF-β signaling components (BMP8A), chromatin remodeling (KDM5C) and metabolic pathways (MDH2). LET dependency analyses also identified TGF-β signaling as key component, cell-death mediations (BAD, BNIP3) and tumor suppressors (ARID2). Common pattern of upregulation across both tumors and libraries was a gradual LET dependent increase of genes associated immune signaling processes (HLAs, interferon response, MX1, etc.) which correlated well with enrichment of pathways found to be related to immune response. Together, this work provides novel insights into the molecular fitness landscape of tumors under conventional photon irradiation and ion beam therapy

Effect of Spirulina supplementation and aerobic exercise on the level of cortisol and body composition in women with type 2 diabetes

Background: Changes in the hypothalamus-pituitary-adrenal axis and obesity play an important role in the development of diabetes. Aim of this study was to investigate the effect of spirulina supplementation and aerobic exercise on serum cortisol level and body composition in women with high BMI type 2 diabetes.Methods: In this semi-experimental study, 28 women with type 2 diabetes and overweight with mean age of 48.4 ±7 and body mass index 29.7±3.33, were randomly assigned to aerobic training groups + spirulina, aerobic training + placebo, spirulina and placebo. The aerobic training program included six weeks and running with a severity of 60-72% of maximum heart rate. The recipient groups received three 500 mg capsules of spirulina daily for six weeks before each meal. Blood samples were collected for pre-test and post-test stages in order to study the variables studied in fasting conditions. Data analysis was performed using one-way ANOVA and t-test with a significant level (p≤0.05) and using SPSS software.Results: Serum levels of cortisol in the aerobic- Spirulina group (p=0.02), aerobic group (p=0.00), and spirulina group (p=0.02) showed a significant decrease from the pre-test to post-test. Also, there was a significant difference in the level of cortisol between aerobic-spirulina group and aerobic group compared to control group (P≤0.05). However, there was no difference between the groups (fat percentage, BMI, WHR) in body composition indicators (P>0.05).Conclusion: Results of Cortisol Measurement and body composition showed that aerobic training along with supplementation with spirulina has a positive effect on the cortisol reduction in women with type 2 diabetes and can therefore reduce stress and improve the health of patients with type 2 diabetes and overweight.Keywords: Aerobic Exercise; Spirulina; Cortisol; Body Combination; Type 2 Diabetes; Overweigh