214 research outputs found

    Multiphysics Modeling and Analysis of a Solar Desalination Process Based on Vacuum Membrane Distillation

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    A hollow fiber vacuum membrane distillation (VMD) module was modeled using finite element analysis, and the results were used to conduct an exergy efficiency analysis for a solar-thermal desalination scheme. The performance of the VMD module was simulated under various operating conditions and membrane parameters. Membrane porosity, tortuosity, pore diameter, thickness, and fiber length were varied, along with feed temperature and feed configuration. In all cases, polarization phenomena were seen to inhibit the performance of the module. Under VMD operation, polarization of salt concentration was seen to be the main determining factor in the reduction of permeate flux. Within the boundary layer, salt concentration was seen to rapidly increase from the feed mass fraction of 0.035 to the saturation point. The increase in salt concentration led to a decrease in saturation pressure, the driving force for separation. Charging the feed into the shell instead of the lumen side of the membranes resulted in a further decrease in permeate flux. It is shown that adding a baffling scheme to the surface of the fibers can effectively reduce polarization phenomena and improve permeate flux. Increasing the overall recovery ratio was seen to increase the exergy efficiency of the system. Exergy efficiency was seen to have almost no dependency on membrane parameters due to the low recovery ratio in a single pass and the high heating duty required to reach the desired temperature for the feed stream

    Correlation between maternal and cord blood leptin and fetal growth

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    Leptin is a protein secreted mainly by the adipocyte in proportion to fat mass. The serum leptin concentration reflects the amount of adipose tissue in the body and has potential role on the fat deposition in the fetus. In the present study, we investigated whether umbilical and maternal serum leptin concentrations correlate with fetal growth. In addition, we determined the relationship between leptin concentration in the maternal and cord blood. We studied 100 newborn infants (48 female and 52 male; gestational age, 34 - 40 weeks) and their mothers at Alzahra hospital in Tabriz city. Serum leptin concentrations were measured by ELISA and linear regression analysis was used to evaluate correlation. In the results, there was no significant correlation between umbilical and maternal leptin concentrations (r = 0.011; p = 0.459) in all study groups. There was a correlation between umbilicalleptin concentration and birth weight of newborns (r = 0.278; p = 0.003) and correlation with body mass index (BMI) of the newborns (r = 0.249; p = 0.006). Maternal leptin concentrations correlated withmaternal weight and BMI (r = 0.277; p = 0.003, r = 0.290; p = 0.002, respectively). There was no correlation between maternal leptin concentrations and birth weight (r = - 0.162; p = 0.054) and with BMIof the newborns (r = - 0.158; p = 0.058). There was gender difference in leptin concentrations in the newborns (r = 0.331; p = 0.00025) with greater level in females. In conclusion, we have shown that theassociation between umbilical serum leptin and birth weight in this and other studies suggests a pivotal role of fetal leptin in regulating fetal growth and development

    The Possible Impact of Obesity on Androgen, Progesterone and Estrogen Receptors (ERα and ERβ) Gene Expression in Breast Cancer Patients

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    Background Obesity has been associated with increased mortality from hormone dependant cancers such as breast cancer which is the most prevalent cancer in women. The link between obesity and breast cancer can be attributed to excess estrogen produced through aromatization in adipose tissue. The role of steroid hormone receptors in breast cancer development is well studied but how obesity can affect the expression pattern of steroid hormones in patients with different grades of breast cancer was the aim of this study. Methods In this case-control study, 70 women with breast cancer participated with different grades of obesity (36 none obese, BMI < 25 kg/m 2 and 34 obese, BMI ≥ 25 kg/m 2 ). The mean age of participants was 44.53 ± 1.79 yr (21–70 yr). The serum level of estrogen, progesterone and androgen determined by ELISA. Following quantitative expression of steroid hormone receptors mRNA in tumor tissues evaluated by Real-time PCR. Patients with previous history of radiotherapy or chemotherapy were excluded. SPSS 16 was used for data analysis and P < 0.05 considered statistically significant. Results The difference in ERα, ERβ and PR mRNA level between normal and obese patients was significant ( P < 0.001). In addition, the expression of AR mRNA was found to be higher than other steroid receptors. There was no significant relation between ERβ gene expression in two groups ( P = 0.68). We observed a significant relationship between ERα and AR mRNA with tumor stage and tumor grade, respectively ( P = 0.023, P = 0.015). Conclusion According to the obtained results, it is speculated that obesity could paly a significant role in estrogen receptors gene expression and also could affect progression and proliferation of breast cancer cells

    The effect of parental medical history on the prevalence of cerebrovascular diseases in their children in an Iran IAN population

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    Introduction: still a controversial issue, family history is known as a risk factor for the development of Cerebrovascular Diseases (CVD). In this study, we aimed to evaluate the relationship between parental history and risk of CVD in their offspring in Iranian population. Methods: Isfahan Cohort Study (ICS) included total 6504 healthy participants which were randomly selected through a two-stage cluster sampling method from three districts. The participants were followed prospectively for 10 years. The diagnosis of CVD were confirmed by expert panelist. Clinically validated history of CVD was established for definition of parental history of CVD. Types of history were categorized into paternal, maternal, both parents, and no history. Results: The prevalence of CVD is generally higher among female offspring compared with male ones (P<0.001). The relative risk of CVD with maternal history was not significant (95CI=0.95-2.29). By adjusted model analysis, history of CVD in both parents affected the risk of CVD in their male children (RR=2.13, P=0.033, 95CI). By crude model analysis, maternal history of CVD (P=0.047), history of CVD in both parents (P=0.032), and maternal history of hypertension (P=0.005) were determined as risk factors of CVD in offspring. Indeed, the mean age of CVD in offspring decreases based on this order: history of hypertension in parents, paternal history of CVD in both parents, maternal history of CVD, and no history (P<0.001). Conclusion: Early and regular screening for CVD development is necessary in female offspring of the families with the present history of CVD from maternal side. This group are at risk and should be considered as the target group for screening and taking preventive measures. © 2018 Iran University of Medical Sciences. All rights reserved

    Cell responses and hemocompatibility of g-HA/PLA composites

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    The objective of this study was to investigate the hemocompatibility and cell responses to some novel poly(L-lactide) (PLA) composites containing surface modified hydroxyapatite particles for potential applications as a bone substitute material. The surface of hydroxyapatite (HA) particles was first grafted with L-lactic acid oligomers to form grafted HA (g-HA) particles. The g-HA particles were further blended with PLA to prepare g-HA/PLA composites. Our previous study has shown significant improvement in tensile properties of these materials due to the enhanced interfacial adhesion between the polymer matrix and HA particles. To further investigate the potential applications of these composites in bone repair and other orthopedic surgeries, a series of in vitro and in vivo experiments were conducted to examine the cell responses and hemocompatibility of the materials. In vitro experiments showed that the g-HA/PLA composites were well tolerated by the L-929 cells. Hemolysis of the composites was lower than that of pure PLA. Subcutaneous implantation demonstrated that the g-HA/PLA composites were more favorable than the control materials for soft tissue responses. The results suggested that the g-HA/PLA composites are promising and safe materials with potential applications in tissue engineering

    Diagnosing and measuring incompatibilities between pairs of services

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    International audienceThis text presents a tool, from its design to its implementation, which detects all behavioural incompatibilities between two service interfaces. Unlike prior work, the proposed solution does not simply check whether two services are incompatible or not, it rather provides detailed diagnosis, including the incompatibilities and for each one the location in the service interfaces where these incompatibilities occur. A measure of similarity between interfaces which considers outputs from the detection algorithm is proposed too. A visual report of the comparison analysis is also provided which pinpoints a set of incompatibilities that cause a behavioural interface not to simulate another one

    Analysis and Verification of Service Interaction Protocols - A Brief Survey

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    Modeling and analysis of interactions among services is a crucial issue in Service-Oriented Computing. Composing Web services is a complicated task which requires techniques and tools to verify that the new system will behave correctly. In this paper, we first overview some formal models proposed in the literature to describe services. Second, we give a brief survey of verification techniques that can be used to analyse services and their interaction. Last, we focus on the realizability and conformance of choreographies.Comment: In Proceedings TAV-WEB 2010, arXiv:1009.330

    Investigating the Correlation between Performance Scores and Energy Consumption of Mobile Web Apps

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    Context. Developers have access to tools like Google Lighthouse to assess the performance of web apps and to guide the adoption of development best practices. However, when it comes to energy consumption of mobile web apps, these tools seem to be lacking. Goal. This study investigates on the correlation between the performance scores produced by Lighthouse and the energy consumption of mobile web apps. Method. We design and conduct an empirical experiment where 21 real mobile web apps are (i) analyzed via the Lighthouse performance analysis tool and (ii) measured on an Android device running a software-based energy profiler. Then, we statistically assess how energy consumption correlates with the obtained performance scores and carry out an effect size estimation. Results. We discover a statistically significant negative correlation between performance scores and the energy consumption of mobile web apps (with medium to large effect sizes), implying that an increase of the performance score tend to lead to a decrease of energy consumption. Conclusions. We recommend developers to strive to improve the performance level of their mobile web apps, as this can also have a positive impact on their energy consumption on Android devices

    Research Paper: Introducing Transthyretin as a differentially expressed protein in washing subtype of Obsessive- Compulsive Disorder

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    Introduction: Obsessive-Compulsive Disorder (OCD) as one of the important mental problems is valuable topic for proteomic research studies to better understand the underlying mechanisms of this disorder. Methods: In this paper, gel-based proteomic was used to investigate the proteome profile of 16 female patients with OCD, washing subtype before and after treatment with fluoxetine and comparing them with 20 healthy female controls. Results: One of the abnormally expressed protein spots in this study was introduced and examined for protein-protein interaction network analysis via Cytoscape and its plug-ins. Transthyretin (TTR) protein showed significant expression changes (fold change=1.7, P < 0.05). While the expression level of TTR is significantly decreased in OCD patients before any treatments, the trend is partially normalized after treatment with fluoxetine in positive responders. Furthermore, TTR interaction profile shows that the proteins interacting with this protein may get affected as this protein expression trend changes in OCD patients. Conclusion: TTR can be considered for further studies to be validated as a potential biomarker for OCD. © The Author(s)
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