Effects of age and task difficulty on postural sway, variability and complexity

This study aimed to examine the effects of age and the task difficulty on postural sway, variability and complexity. The participants were 90 able-bodied individuals from children (n = 39; age: 5.89 ± 0.94 years), young adults (n = 30; age: 23.23 ± 1.61 years) and older adults (n = 21; age: 64.59 ± 5.24 years) that took part in different balance tasks that were had different levels of cognitive and physical challenges. The main dependent variables were postural sway area, postural variability and postural complexity. The participants stood on a standard force plate for 10 seconds in each task condition, and the centre of pressure displacement was collected at 100 sampling frequency. The results of this study showed that children and older adults, in the more difficult tasks, had greater sway area and complexity and less postural variability. In addition, there was a linear trend in the stability measures as the difficulty of the task was increased. In conclusion, special populations, such as children and older adults, were more sensitive to the balance changes and used active control mechanisms to minimise the risk of losing balance in more challenging conditions

Numerical simulation of gas composition tracking in a gas transportation network

In previous papers of the authors, a new formulation for isothermal flow of gas mixtures with given constant composition in a transportation network including usual devices has been introduced and solved. However, in real networks, different gas qualities are introduced from different entry points. In this case, it is important to track the quality along the network over time and therefore a multi-species model has to be used. The main objective of the present paper is to introduce a model allowing us to simulate the evolution of the gas composition, at each point in the network and over time, and then to couple it with the flow model. The model for tracking the gas composition consists of a system of first order partial differential equations, one per pipe and per species, which are coupled together at the nodes by imposing the mass conservation equation for each species. It is important to notice that the coupling condition at the nodes guarantees that the numerical scheme conserves the mass of each species along the time. In order to validate the overall methodology, it is applied to a test case on a real network. Numerical results show good agreement with measurementsThe first author has been partially supported by ERDF and Xunta de Galicia (Spain) under grant ED431C 2021/15 and by Ministerio de Economía y Competitividad (Spain) and ERDF under research project MTM2017-86459-RS

Nova formulacija optimizacijskog problema za određivanje optimalnog dosega zona udaljenih releja uz stohastičko modeliranje neodređenosti

In this paper, by probabilistic modeling of uncertainties, the problem of determining the reach setting of distance relay zones is presented as a new optimization problem. For this purpose, uncertainties are modeled based on their probability density functions. Then, by using the Monte-Carlo process, the impedance seen by the distance relay is obtained. In this paper, probabilistic sensitivity and selectivity indices are defined for each zone of the distance relay. Therefore, the problem of determining the optimum reach setting of distance relay for each zone is converted to an optimization problem with the objective of maximizing of the probabilities indices of sensitivity and selectivity. The objective function and the constraints of the optimization problem are defined based on the protection philosophy of each of the three different zones of the distance relay. Considering the fact that the optimization problem is nonlinear and non-convex, the particle swarm optimization (PSO) is used to solve this problem. The proposed optimization problem is applied on a 9-bus network, and the reach settings of distance relays are calculated and compared with those of the conventional approach. Also, uncertainties are prioritized based on the amount of their impact on the probabilistic indices of sensitivity and selectivity.U ovom radu je problem određivanja dosega zona udaljenih releja uz stohastičko modeliranje neodređenosti predstavljen kao novi optimizacijski problem. S tim u vezi, neodređenosti su modelirane na osnovu njihovih funkcija gustoće vjerojatnosti. Potom je korištenjem Monte-Carlo procesa dobivena impedancija koju vidi udaljeni relej. U ovom radu su definirani indeksi stohastičke osjetljivosti i selektivnosti za svaku zonu udaljenog releja. Problem određivanja optimalnog dosega udaljenog releja za svaku zonu je transformiran u optimizacijski problem s kriterijem maksimiziranja stohastičkih indeksa ostjetljivosti i selektivnosti. Kriterijska funkcija i ograničenja optimizacijskog problema definirani su na osnovu strategije zaštite svake od tri različite zone udaljenog releja. Uzimajući u obzir da je dobiveni optimizacijski problem nelinearan i nekonveksan, za dobivanje rješenja je u radu korištena optimizacija rojem čestica. Predloženi optimizacijski problem primijenjen je na mrežu s 9 sabirnica, pri čemu je izračunati doseg udaljenih releja uspoređen s konvencionalnim pristupom. Također, prioritet neodređenosti određen je na osnovu njihovog utjecaja na stohastičke indekse osjetljivosti i selektivnosti

Entropy generation of pseudo-plastic non-Newtonian nanofluids in circular duct under constant wall temperature

In this paper the second law analysis of thermodynamic irreversibilities in pseudo-plastic non-Newtonian nanofluids through a circular duct under uniform wall temperature thermal boundary have been carried out for laminar flow condition. This nanofluid consists of sodium carboxymethyl cellulose (CMC)–water and two different types of nanoparticles; namely, CuO and Al2O3. Entropy generation is obtained for various Power law number, various volume concentration of nanoparticles, various dimensionless temperature and various Reynolds number. It is found that with the decreasing Power law number and duct length values, total entropy generation at fixed Reynolds number decreases and with increasing wall temperature values, total entropy generation increases, also entropy generation decreases with increasing volume concentration of nanoparticles

SWAT Modeling of Non-Point Source Pollution in Depression-Dominated Basins under Varying Hydroclimatic Conditions

Non-point source (NPS) pollution from agricultural lands is the leading cause of various water quality problems across the United States. Particularly, surface depressions often alter the releasing patterns of NPS pollutants into the environment. However, most commonly-used hydrologic models may not be applicable to such depression-dominated regions. The objective of this study is to improve water quantity/quality modeling and its calibration for depression-dominated basins under wet and dry hydroclimatic conditions. Specifically, the Soil and Water Assessment Tool (SWAT) was applied for hydrologic and water quality modeling in the Red River of the North Basin (RRB). Surface depressions across the RRB were incorporated into the model by employing a surface delineation method and the impacts of depressions were evaluated for two modeling scenarios, MS1 (basic scenario) and MS2 (depression-oriented scenario). Moreover, a traditional calibration scheme (CS1) was compared to a wet-dry calibration scheme (CS2) that accounted for the effects of hydroclimatic variations on hydrologic and water quality modeling. Results indicated that the surface runoff simulation and the associated water quality modeling were improved when topographic characteristics of depressions were incorporated into the model (MS2). The Nash–Sutcliffe efficiency (NSE) coefficient indicated an average increase of 30.4% and 19.6% from CS1 to CS2 for the calibration and validation periods, respectively. Additionally, the CS2 provided acceptable simulations of water quality, with the NSE values of 0.50 and 0.74 for calibration and validation periods, respectively. These results highlight the enhanced capability of the proposed approach for simulating water quantity and quality for depression-dominated basins under the influence of varying hydroclimatic conditions

The effects of fin parameters on the solidification of PCMs in a fin-enhanced thermal energy storage system

In the present study, a triplex-tube, employing fin-enhanced phase change materials (PCMs), as a thermal energy storage (TES) system was studied numerically. The main flaw of the PCMs is their low thermal conductivity that restricts their e ectiveness for energy storage applications. Metallic (copper) fins are added to the geometry of the system to improve their function by extending the heat transfer area. The e ects of the presence, configuration, and dimensions of copper fins were investigated to understand the best design for minimizing the solidification time and achieving the best performance enhancement for the TES system selected for this study. The results revealed that the best performance belonged to fins with a mix configuration, with an attachment angle of 90 and the length and width of 28 mm and 1 mm, respectively. Using this configuration could reduce the required time for complete solidification by around 42% compared to the system without fins. Moreover, it was concluded that increasing the length of the fin could o er its positive e ect for enhancing the performance of TES system up to an optimal point only while increasing the width showed a diverse influence. Furthermore, the angles between the tube surface and the fin direction were investigated and 90 was found to be the best choice for the TES case selected in this study. In addition, placement of the fins on the surface of internal or external tube or mix method did not show a significant e ect while placing the fins on the external surface of the tube showed even a negative impact on the performance of the TES system compared with when no fins were applied.http://www.mdpi.com/journal/energiesam2020Mechanical and Aeronautical Engineerin

Radioprotective effects of Silymarin on the sperm arameters of NMRI mice irradiated with γ-rays.

Free radicals and reactive oxygen species (ROS) are generated using various endogenous systems or from external sources such as exposure to different physiochemicals. Ionizing radiation damage to the cell can be caused by the direct or indirect effects of radiotherapy processes. Silymarin (SM), a flavanolignan compound, has been identified as a natural potent antioxidant with cytoprotection activities due to scavenging free radicals. The aim of the present study was to evaluate the radioprotective effect of SM on sperm parameters of mice induced by γ-rays. A total number of 40 adult, male NMRI mice were randomly divided into four equal groups. The control group was neither treated with SM nor irradiated by γ-rays. The second group was only irradiated with 2Gy of γ-rays. The third group was firstly treated with 50mg/kg of SM for 7 consecutive days, and one day later, last injections were irradiated by 2Gy of γ-rays. The fourth groups received only 50mg/kg of SM for 7 consecutive days. All the animals were treated intraperitoneally. Histopathological and morphometrical examinations were performed. The data were analyzed using ANOVA and Tukey post hoc test. A value of p<0.05 was considered significant. The results showed that in the radiation-only group when compared with those treated with SM and irradiated, a significant different was observed in testicular parameters and DNA damage (p<0.05). In conclusion, SM can be considered as a promising herbal radioprotective agent in complementary medicine which may play an important role to protect normal spermatocytes against possible effects of γ-radiation-induced cellular damage

Comparative expression profile of orphan receptor tyrosine kinase ROR1 in Iranian patients with lymphoid and myeloid leukemias

It has recently been shown that ROR1, a member of the receptor tyrosine kinase family, is overexpressed in leukemic B cells of Chronic Lymphocytic Leukemia (CLL) and a subset of Acute Lymphoblastic Leukemia (ALL). In this comparative study the expression profile of ROR1 mRNA was investigated in Iranian patients with CLL and Acute Myelogenous Leukemia (AML) and the results were compared with those previously reported in our Iranian ALL patients. RT-PCR was performed on bone marrow and/or peripheral blood samples of 84 CLL and 12 AML patients. CLL samples were classified into immunoglobulin heavy chain variable region (IGHV) gene mutated (n = 55) and unmutated (n = 29) and also indolent (n = 42) and progressive (n = 39) subtypes. ROR1 expression was identified in 94% of our CLL patients, but none of the AML patients expressed ROR1. No significant differences were observed between different CLL subtypes for ROR1 expression. Taken together the present data and our previous results on ROR1 expression in ALL, our findings propose ROR1 as a tumor-associated antigen overexpressed in a large proportion of lymphoid (CLL and ALL), but not myeloid (AML) leukemias. Expression of ROR1 seems to be associated to lineage and differentiation stages of leukemic cells with a potential implication for immunotherapy.Tehran University of Medical SciencesPublishe

Comparative expression profile of orphan receptor tyrosine kinase ror1 in iranian patients with lymphoid and myeloid leukemias

It has recently been shown that ROR1, a member of the receptor tyrosine kinase family, is overexpressed in leukemic B cells of Chronic Lymphocytic Leukemia (CLL) and a subset of Acute Lymphoblastic Leukemia (ALL). In this comparative study the expression profile of ROR1 mRNA was investigated in Iranian patients with CLL and Acute Myelogenous Leukemia (AML) and the results were compared with those previously reported in our Iranian ALL patients. RT-PCR was performed on bone marrow and/or peripheral blood samples of 84 CLL and 12 AML patients. CLL samples were classified into immunoglobulin heavy chain variable region (IGHV) gene mutated (n=55) and unmutated (n=29) and also indolent (n=42) and progressive (n=39) subtypes. ROR1 expression was identified in 94% of our CLL patients, but none of the AML patients expressed ROR1. No significant differences were observed between different CLL subtypes for ROR1 expression. Taken together the present data and our previous results on ROR1 expression in ALL, our findings propose ROR1 as a tumor-associated antigen overexpressed in a large proportion of lymphoid (CLL and ALL), but not myeloid (AML) leukemias. Expression of ROR1 seems to be associated to lineage and differentiation stages of leukemic cells with a potential implication for immunotherapy.Tehran University of Medical Sciences and the Ministry of Health and Medical Education of Iran.Publishe

Association between the rs2241883 polymorphism of the fatty acid-binding protein-1 (FABP1) gene and obesity in a population of MASHAD study cohort

Funding Information: We would like to thank Mashhad University of Medical Sciences Research Council for their financial supports.Peer reviewedPublisher PD