Amphiphilic A3B3 miktoarm star polymer: synthesis and micellization study by fluorometry, TEM and DLS techniques

Abbas Rezaei,Faezeh Aminian,Hossein Behniafar 한국고분자학회 2023 Macromolecular Research Vol.31 No.9

A new amphiphilic six-armed A3B3-type miktoarm star polymer was synthesized starting from a triazidohydrin as the core. First, three hydrophobic arms of polycaprolactone were formed on the core through ring-opening polymerization (core-first method). Next, presynthesized PEG-based hydrophilic arms were attached to the previous structure using click chemistry (arm-first method). In the vicinity of the junction of the hydrophilic arms to the core, bio-reducible disulfide bonds were embedded. The prepared star polymer was characterized by elemental analysis and spectroscopic techniques (FT-IR and H-NMR). Using transmission electron microscopy (TEM) it was found that the amphiphilic macromolecules at concentrations higher than critical micelle concentration (CMC) formed spherical micelles with an average diameter below 100 nm. The CMC of the synthesized amphiphilic polymer in aqueous solution was determined by fluorometric method via examining the emission spectra of an organic probe. Thus, it was measured to be 1.76 × 10–3 mg/mL (3.90 × 10–7 M). In addition, dynamic light scattering measurements indicated that the spherical micelles had a mean hydrodynamic diameter (DH) of ~ 70 nm and polydispersity index of 0.17.

Letrozole, an aromatase inhibitor, improves seminal parameters and hormonal profile in aged endangered Markhoz bucks

Rezaei, Ako,Vaziry, Asaad,Farshad, Abbas Asian Australasian Association of Animal Productio 2022 Animal Bioscience Vol.35 No.11

Objective: Letrozole, a potent aromatase inhibitor, is known to have the potential to modify male reproductive function by altering sex hormone levels. This study aimed to evaluate the semen and testicular characteristics and hormonal profile of aged Mrakhoz bucks (Capra hircus) treated with letrozole. Methods: Twelve Markhoz male goats, aged between 4.5 to 5.5 years with an average body weight (BW) of 61.05±4.97 kg were used for the study. Animals were randomly divided into two equal groups and subcutaneously received either 0.25 mg/kg BW of letrozole or a control every week for 2 months. The semen collections were performed every 10 days, and blood samples and testicular biometric records were collected at 20 days intervals. Results: Letrozole causes increased testosterone and follicle-stimulating hormone levels, testosterone to estradiol ratio, semen index and reaction time during the period from 20th to 60th days (p<0.05). Furthermore, letrozole-treated bucks had higher semen volume, sperm concentration, and total sperm per ejaculate from 30th to 60th days (p<0.05). However, no differences occurred between the groups in scrotal circumference, relative testicular volume, semen pH, abnormality, acrosome integrity, and membrane integrity of sperm during the study (p>0.05). The serum luteinizing hormone levels, sperm viability, motility, and progressive motility increased, and estradiol levels decreased after 40th to 60th days of letrozole treatment (p<0.05). Conclusion: Letrozole application to aged Markhoz bucks provokes reproductive hormonal axis which, in turn, induces enhancement of semen production and quality.

Performance analysis and modeling of catalytic trickle-bed reactors: a comprehensive review

Abbas Azarpour,Nima Rezaei,Sohrab Zendehboudi 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Trickle-bed reactors (TBRs) are extensively used in industry. There have been great progresses in designand control of the TBRs. However, more improvements are required in the performance/operation ofTBRs. These improvements can lead to more efficient process control and further reduction of the operationcosts. In terms of process efficiency, the product quality can be improved since a large number ofthe TBRs are used in purification processes. In terms of operation costs, the process improvement canresult in longer utilization of the catalysts because the catalytic TBRs’ operations usually suffer fromthe deactivation phenomenon for expensive catalysts. Hydrodynamic parameters play significant rolesin the control and operation of TBRs. We provide comprehensive information and discussion on TBRsapplication and hydrodynamic characteristics. Moreover, a systematic methodology is proposed todevelop a TBR mathematical model. A detailed review on the previous TBRs studies is presented, andtechnical issues in their design and operation are discussed. In addition, current challenges in the TBRmodeling are summarized, and further research plans/topics are suggested. This review provides anexhaustive knowledge and practical and theoretical tips that can be employed to more efficaciouslymodel targeted TBR processes, leading to better understanding of the process behaviours, and more efficientoperation of the relevant plants.

Product quality control in hydropurification process by monitoring reactor feed impurities: Dynamic mathematical modeling

Abbas Azarpour,Nima Rezaei,Sohrab Zendehboudi 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.92 No.-

Control of product quality plays a crucial role in petrochemical industries. In this paper, we propose a newstrategy to control the quality of purified terephthalic acid (PTA) product. In this approach, the PTAquality is controlled by monitoring the concentration of the main impurity in the hydropurificationprocess, which is 4-carboxybenzaldehyde (4-CBA) in the crude terephthalic acid (CTA) powder. To attainthe research objectives, a dynamic dispersion model is developed in the face of catalyst deactivation,considering the vital operating parameters. The CTA powder streams with low and high 4-CBAconcentrations can be effectively used through a proper (and controlled) mixing procedure. This strategycan be applied by controlling the ratio of the massflowrates of the two streams, having high and lowconcentrations. The positive effect of H2 partial pressure on the system performance can be implementedby a small decrease in reactor temperature. Off-spec PTA powder can be used with the CTA powder havinga high 4-CBA concentration. Increasing temperature accelerates the reduction rate of the Pd/C catalystsurface area, leading to an unfavorable sintering phenomenon. The decreased activity of Pd/C catalyst isin good agreement with the normalized ratio of decrease in the surface area of pure Pd with increasingtemperature.

Design and Optimization of Full Comparator Based on Quantum-Dot Cellular Automata

Mohsen Hayati,Abbas Rezaei 한국전자통신연구원 2012 ETRI Journal Vol.34 No.2

Quantum-dot cellular automata (QCA) is one of the few alternative computing platforms that has the potential to be a promising technology because of higher speed, smaller size, and lower power consumption in comparison with CMOS technology. This letter proposes an optimized full comparator for implementation in QCA. The proposed design is compared with previous works in terms of complexity, area, and delay. In comparison with the best previous full comparator, our design has 64% and 85% improvement in cell count and area, respectively. Also, it is implemented with only one clock cycle. The obtained results show that our full comparator is more efficient in terms of cell count, complexity, area, and delay compared to the previous designs. Therefore, this structure can be simply used in designing QCA-based circuits.

Towards modeling growth of apricot fruit: finding a proper growth model

Jannatizadeh Abbasali,Rezaei Mehdi,Rohani Abbas,Lawson Shaneka,Fatahi Reza 한국원예학회 2023 Horticulture, Environment, and Biotechnology Vol.64 No.2

Fruit growth patterns are often exploited in predictions of fi nal fruit size and to inform planting and harvesting decisions. Ten local apricot ( Prunus armeniaca ) varieties with superior genotypes (two early-ripening, fi ve mid-ripening and three late-ripening varieties) were assessed using 20 nonlinear regression models (NRMs) and a radial basis function (RBF) neural network model. Fruit diameter and weight measurements for each genotype were collected at four-day intervals from fruit set to commercial harvest. Patterns based on diameter and weights were attributed to each genotype. Among the NRM tested, only four were able to fl awlessly predict apricot diameter and weight during the growing season. In addition, comparison of nonlinear regression methods with the neural network indicated than the RBF model displayed fewer prediction errors than the NRMs. The RBF model predicted fruit size with a coeffi cient of determination (R 2 value) greater than 0.95. Therefore, predictions of growth patterns in fruit trees can be accomplished with neural network modeling.

Double Gate MOSFET Modeling Based on Adaptive Neuro-Fuzzy Inference System for Nanoscale Circuit Simulation

Mohsen Hayati,Majid Seifi,Abbas Rezaei 한국전자통신연구원 2010 ETRI Journal Vol.32 No.4

As the conventional silicon metal-oxide-semiconductor field-effect transistor (MOSFET) approaches its scaling limits, quantum mechanical effects are expected to become more and more important. Accurate quantum transport simulators are required to explore the essential device physics as a design aid. However, because of the complexity of the analysis, it has been necessary to simulate the quantum mechanical model with high speed and accuracy. In this paper, the modeling of double gate MOSFET based on an adaptive neuro-fuzzy inference system (ANFIS) is presented. The ANFIS model reduces the computational time while keeping the accuracy of physics-based models, like non-equilibrium Green’s function formalism. Finally, we import the ANFIS model into the circuit simulator software as a subcircuit. The results show that the compact model based on ANFIS is an efficient tool for the simulation of nanoscale circuits.

Improved Broiler Chick Performance by Dietary Supplementation of Organic Zinc Sources

Jahanian, Rahman,Moghaddam, Hasan Nassiri,Rezaei, Abbas Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.9

Two inorganic (zinc sulfate and zinc oxide) and three organic (zinc acetate, zinc-methionine, and zinc-lysine) zinc sources were evaluated for their effects on the performance and carcass characteristics of broiler chicks. The birds were randomly assigned to one control (non-supplemented) and 15 treatment (supplemented) groups consisting of four replicates of 10 chicks each in a $5{\times}3$ factorial arrangement of treatments (five zinc sources and three supplemental zinc levels). Birds were kept in floor pens in a temperature-controlled room from 1 to 42 d of age and fed a non-supplemented basal diet (control) or the basal diet supplemented with 40, 80 or 120 mg/kg of Zn as mentioned sources. Dietary zinc source had considerable effect on feed intake in all experimental periods. Increasing Zn level from 80 to 120 mg/kg decreased the average feed intake in the growth stage (p<0.01) and also in the entire experimental period (p<0.001). Similarly, the average daily gain during the entire trial period was affected by the type of Zn source (p<0.001) and supplemental level (p<0.01). One degree of freedom contrast comparisons showed that the inclusion of organic zinc sources into the diets caused significant increases in feed intake and body gain when compared with inorganic counterparts. Except in wk 1, dietary supplementation with organic sources improved (p<0.05) feed conversion ratio; FCR values were not affected by dietary Zn source or supplementation level. Breast meat yield increased with supplemental levels of organic Zn sources; however, other carcass parameters were not affected by dietary Zn source. On the other hand, organic versus inorganic zinc supplementation caused a significant increase in liver, breast and carcass weight percentages. The present findings suggest that supplemental levels of organic Zn compounds had beneficial effects on broiler performance, and Zn requirements can be reduced using these feed supplements in poultry rations.

Alteration of TGFB1, GDF9, and BMPR2 gene expression in preantral follicles of an estradiol valerate-induced polycystic ovary mouse model can lead to anovulation, polycystic morphology, obesity, and absence of hyperandrogenism

Reza Asghari,Vahid Shokri-Asl,Hanieh Rezaei,Mahmood Tavallaie,Mostafa Khafaei,Amir Abdolmaleki,Abbas Majdi Seghinsara 대한생식의학회 2021 Clinical and Experimental Reproductive Medicine Vol.48 No.3

Objective: In humans, polycystic ovary syndrome (PCOS) is an androgen-dependent ovarian disorder. Aberrant gene expression in folliculogenesis can arrest the transition of preantral to antral follicles, leading to PCOS. We explored the possible role of altered gene expression in preantral follicles of estradiol valerate (EV) induced polycystic ovaries (PCO) in a mouse model.Methods: Twenty female balb/c mice (8 weeks, 20.0±1.5 g) were grouped into control and PCO groups. PCO was induced by intramuscular EV injection. After 8 weeks, the animals were killed by cervical dislocation. Blood serum (for hormonal assessments using the enzyme-linked immunosorbent assay technique) was aspirated, and ovaries (the right ovary for histological examinations and the left for quantitative real-time polymerase) were dissected. Results: Compared to the control group, the PCO group showed significantly lower values for the mean body weight, number of preantral and antral follicles, serum levels of estradiol, luteinizing hormone, testosterone, and follicle-stimulating hormone, and gene expression of TGFB1, GDF-9 and BMPR2 (p<0.05). Serum progesterone levels were significantly higher in the PCO animals than in the control group (p<0.05). No significant between-group differences (p>0.05) were found in BMP6 or BMP15 expression. Conclusions: In animals with EV-induced PCO, the preantral follicles did not develop into antral follicles. In this mouse model, the gene expression of TGFB1, GDF9, and BMPR2 was lower in preantral follicles, which is probably related to the pathologic conditions of PCO. Hypoandrogenism was also detected in this EV-induced murine PCO model.

The Effect of Lactobacillus acidophilus PTCC 1643 on Cultured Intestinal Epithelial Cells Infected with Salmonella enterica serovar Enteritidis

Mona Moshiri,Mohammad Mehdi Soltan Dallal,Farhad Rezaei,Masoumeh Douraghi,Laleh Sharifi,Zahra Noroozbabaei,Mehrdad Gholami,Abbas Mirshafiey 질병관리본부 2017 Osong Public Health and Research Persptectives Vol.8 No.1

Objectives: Gastrointestinal disorders caused by Salmonella enterica serovar Enteritidis (SesE) are a significant health problem around the globe. Probiotic bacteria have been shown to have positive effects on the immune responses. Lactobacillus acidophilus was examined for its capability to influence the innate immune response of HT29 intestinal epithelial cells towards SesE. The purpose of this work was to assess the effect of L. acidophilus PTCC 1643 on cultured intestinal epithelial cells infected with SesE. Methods: HT29 cells were cultured in Roswell Park Memorial Institute medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin. The cells were treated with L. acidophilus PTCC 1643 after or before challenge with SesE. At 2 and 4 hours post-infection, we measured changes in the expression levels of TLR2 and TLR4 via real-time polymerase chain reaction. Results: Treatment with L. acidophilus inhibited SesE-induced increases in TLR2 and TLR4 expression in the infected HT29 cells. Moreover, the expression of TLR2 and TLR4 in cells that were pretreated with L. acidophilus and then infected with SesE was significantly higher than that in cells infected with SesE without pretreatment. Taken together, the results indicated that L. acidophilus had an anti-inflammatory effect and modulated the innate immune response to SesE by influencing TLR2 and TLR4 expression. Conclusion: Our findings suggested that L. acidophilus PTCC 1643 was able to suppress inflammation caused by SesE infection in HT29 cells and reduce TLR2 and TLR4 expression. Additional in vivo and in vitro studies are required to further elucidate the mechanisms underlying this anti-inflammatory effect.