The effects of beam-column connections on behavior of buckling-restrained braced frames

Mohammad Ali Hadianfard,Fateme Eskandari,Behtash JavidSharifi 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.3

Buckling Restrained Braced (BRB) frames have been widely used as an efficient seismic load resisting system in recent years mostly due to their symmetric and stable hysteretic behavior and significant energy dissipation capacity. In this study, to provide a better understanding of the behavior of BRB frames with various beam-column connections, a numerical study using non-linear finite element (FE) analysis is conducted. All models are implemented in the Abaqus software package following an explicit formulation. Initially, the results of the FE model are verified with experimental data. Then, diverse beam-column connections are modeled for the sake of comparison from the shear capacity, energy dissipation and frame hysteresis behavior points of view until appropriate performance is assessed. The considered connections are divided into three different categories: (1) simple beam-column connections including connection by web angle and connection by seat angle; (2) semi-rigid connection including connection by web and seat angles; and (3) rigid beam-column connections by upper-lower beam plates and beam connections with web and flange splices. Results of the non-linear FE analyses show that these types of beam-column connections have little effect on the maximum story drift and shear capacity of BRB frames. However, the connection type has a significant effect on the amount of energy dissipation and hysteresis behavior of BRB frames. Also, changes in length and thickness of the angles in simple and semi-rigid connections and changes in length and thickness of plates in rigid connections have slight effects (less than 4%) on the overall frame behavior.

Antenna Selection and Power Allocation for Energy Efficient MIMO Systems

Mahdi Eskandari,Ali Mohamad Doost-Hoseini,정재훈,이인규 한국통신학회 2018 Journal of communications and networks Vol.20 No.6

In this paper, we investigate a new solution for theenergy efficiency (EE) maximization and power allocation problemin point-to-point multiple-input multiple-output (MIMO) spatialmultiplexing schemes. Different from conventional energyefficientoptimization approaches that require iterative numericalalgorithms, we derive an optimal solution in a closed form, whichprovides an insight upon the relation between the optimum EE andsystem parameters such as circuit power and channel conditions. In addition, using the proposed closed form function, we present anupper bound on the optimum EE in terms of the full active transmitantennas parameters. Based on the derived upper bound, we alsopropose a new antenna selection algorithm which achieves almostthe same performance as the optimum solution with much reducedcomplexity.

Clinical significance of cell-free DNA as a prognostic biomarker in patients with diffuse large B-cell lymphoma

Mahsa Eskandari,Saba Manoochehrabadi,Hossein Pashaiefar,Mohammad Ali Zaimy,Mohammad Ahmadvand 대한혈액학회 2019 Blood Research Vol.54 No.2

BackgroundCell-free DNA (cfDNA) has the potential to serve as a non-invasive prognostic biomarker in some types of neoplasia. The investigation of plasma concentration of cfDNA may re-veal its use as a valuable biomarker for risk stratification of diffuse large B-cell lymphoma (DLBCL). The present prognostic value of plasma cfDNA has not been widely confirmed in DLBCL subjects. Here, we evaluated cfDNA plasma concentration and assessed its potential prognostic value as an early DLBCL diagnostic tool.MethodscfDNA concentrations in plasma samples from 40 patients with DLBCL during diagnosis and of 38 normal controls were determined with quantitative polymerase chain reaction (qPCR) for the multi-locus L1PA2 gene.ResultsStatistically significant elevation in plasma cfDNA concentrations was observed in pa-tients with DLBCL as compared to that in normal controls (P<0.05). A cutoff point of 2.071 ng/mL provided 82.5% sensitivity and 62.8% specificity and allowed successful discrimination of patients with DLBCL from normal controls (area under the curve=0.777; P=0.00003). Furthermore, patients with DLBCL showing higher concen-trations of cfDNA had shorter overall survival (median, 9 mo; P=0.022) than those with lower cfDNA levels. In addition, elevated cfDNA concentration was significantly asso-ciated with age, B-symptoms, International Prognostic Index (IPI) score, and different stages of disease (all P<0.05).ConclusionQuantification of cfDNA with qPCR at the time of diagnosis may allow identification of patients with high cfDNA concentration, which correlates with aggressive clinical out-comes and adverse prognosis.

Effects of phosalone consumption via feeding with or without sodium bentonite on performance, blood metabolites and its transition to milk of Iranian Baluchi sheep

( Mohsen Kazemi ),( Ameneh Eskandary Torbaghan ),( Abdoul Mansour Tahmasbi ),( Reza Valizadeh ),( Abbas Ali Naserian ) 한국동물자원과학회 2017 한국축산학회지 Vol.59 No.5

Background: Transfer of pesticides from environment to animal products is inevitable, so the purpose of the present work was to evaluate phosalone consumption via feeding with or without sodium bentonite (SB) on performance, blood metabolites and its transition to milk of Iranian Baluchi sheep. Methods: Twenty Baluchi ewes were divided into four treatments (P1 as control, P2, P3, and P4) of five animals in which phosalone, an organophosphate pesticide, was given via diet (only for P2 and P3) at a dose of 280 mg/ sheep/day for 63 consecutive days. The SB (32 g/sheep/day; for P3 and P4) was also evaluated for its ability to reduce deleterious effects of phosalone in the sheep diets. The control group (P1) did not receive any phosalone and SB during the experiment. Sampling was conducted in two periods of time including weeks 5 and 9. Results: Phosalone residues were observed in the milk samples of P2 and P3 groups during two sampling periods. During period 1, the transfer rate of phosalone from feed to milk was 0.23 and 0.02%, respectively for the contaminated diets (P2 and P3), which is relatively similar to period 2 (0.22 and 0.02%). Only 0.34 (period 1) and 0. 36% (period 2) of phosalone residue are excreted in the feces of P2 group following its daily consumption. Transfer of phosalone from feed to milk was affected (P < 0.05) by the dietary inclusion of a commercial SB, as it (SB) decreased excretion of phosalone via milk (P3). The phosalone and SB alone or together had no significant effect (P > 0.05) on the dry matter intake (DMI) and body weight (BW) gain, but feed efficiency, milk production, milk fat, dry matter (DM) and organic matter (OM) digestibility, acetylcholinesterase (AChE) inhibitory activity, hemoglobin (Hb), red blood cell (RBC), serum glutamic pyruvic transaminase (SGPT), serum glutamic oxaloacetic transaminase (SGOT), albumin and mean corpuscular hemoglobin concentration (MCHC) affected by the treatments in period 1 or 2 (P < 0.05). The Hb, RBC, and MCHC were significantly decreased (P < 0.05) by about 9.72, 20.77, and 9.71%, respectively in the group P2 as compared to those of the control group during period 1. The AChE inhibitory activity (period 1 and 2) significantly increased when phosalone administered via the diet (P < 0.05). Conclusions: Although there were no adverse effects on the performance of sheep following the intake of phosalone alone (P2 vs. P1), but other research on the long and short times to the phosalone in high and low doses with more animals is suggested. Overall, compared to the control group, addition of SB in the diet of sheep improved nutrient digestibility, animal performance, and milk health.

Red Grape Seed Extract Improves Lipid Profiles and Decreases Oxidized Low-Density Lipoprotein in Patients with Mild Hyperlipidemia

Seyed-Mostafa Razavi,Sharareh Gholamin,Ali Eskandari,Nakta Mohsenian,Amir Ghorbanihaghjo,Abbas Delazar,Nadereh Rashtchizadeh,Maryam Keshtkar-Jahromi,Hassan Argani 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.3

Hyperlipidemia can lead to atherosclerosis by lipoprotein deposition inside the vessel wall and oxidative stress induction that leads to the formation of atherosclerotic plaque. Oxidized low-density lipoprotein particles (Ox-LDL) have a key role in the pathogenesis of atherosclerosis. The lipid-lowering properties and antioxidants of the grape seed can be beneficial in atherosclerosis prevention. We conducted a randomized double-blind placebo-controlled crossover clinical trial. Fifty-two mildly hyperlipidemic individuals were divided into two groups that received either 200 mg/day of the red grape seed extract (RGSE) or placebo for 8 weeks. After an 8-week washout period, the groups were crossed over for another 8 weeks. Lipid profiles and Ox-LDL were measured at the beginning and the end of each phase. RGSE consumption reduced total cholesterol (−10.68±26.76 mg/dL, P=.015), LDL cholesterol (−9.66±23.92 mg/dL, P=.014), and Ox-LDL (−5.47±12.12 mg/dL, P=.008). While triglyceride and very low–density lipoprotein cholesterol were decreased and high-density lipoprotein cholesterol was increased by RGSE, the changes were not statistically significant. RGSE consumption decreases Ox-LDL and has beneficial effects on lipid profile—consequently decreasing the risk of atherosclerosis and cardiovascular disorders—in mild hyperlipidemic individuals.