49 results on '"Ebrahimi, Mohammad"'
Search Results
2. New hydroxylammonium-based protic ionic liquids: Influence of cation and anion structure on thermal, viscosity and conductive properties
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Ebrahimi, Mohammad, Kobzar, Yaroslav, Kujawski, Wojciech, and Fatyeyeva, Kateryna
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- 2024
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3. CORBES: Radiation belt survey with international small satellite constellation
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Wu, Ji, Deng, Li, Praks, Jaan, Anger, Marius, Oleynik, Philipp, Hajdas, Wojciech, Wang, Jin-Dong, Zhang, Shen-Yi, Zhou, Bin, Zeng, Li, Cao, Jinbin, Fischer, David, Liu, Shuang, Chen, Wen, Wu, Fan, Xi, Rui-Chen, Li, Xinlin, Walter Abrahao, Dos-Santos, Marcos Denardini, Clezio, Li, Yulun, Yang, Xiao-Chao, Dai, Lei, Ma, Ying-Qi, Yu, Tian, Cai, Ming-hui, Yang, Hao-Liang, Ebrahimi, Mohammad, Maurizio, Falanga, Kalegaev, Vladimir, Li, Wen, Miyoshi, Yoshizumi, Nakamura, Rumi, Petrukovich, Anatoli, Baker, Daniel, and Worms, Jean-Claude
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- 2024
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4. Down-regulating CD19 surface markers expression correlates with infectious bursal disease virus replication
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Shahsavandi, Shahla, Torabi, Samira, Ebrahimi, Mohammad Majid, and Ghadiri, Mohammad Bagher
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- 2023
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5. Estimation of soil texture by fusion of near-infrared spectroscopy and image data based on convolutional neural network
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Vakilzadeh Ebrahimi, Mohammad Kazem, Lee, Hansaem, Won, Jongho, Kim, Seonghwan, and Park, Simon S.
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- 2023
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6. Tween 80 improves the infectivity of BCL1 cell-adapted infectious bursal disease virus
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Shahsavandi, Shahla, Ebrahimi, Mohammad Majid, Ghadiri, Mohammad Bagher, and Samiee, Mohammad Reza
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- 2022
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7. Ultrasensitive early detection of insulin antibody employing novel electrochemical nano-biosensor based on controllable electro-fabrication process
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Farrokhnia, Mohammadreza, Amoabediny, Ghassem, Ebrahimi, Mohammad, Ganjali, Mohammadreza, and Arjmand, Mohammad
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- 2022
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8. Numerical algorithm for nonlinearity compensation of hardly constrained actuation for trajectory tracking control of deadzone-included dynamic systems.
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Ebrahimi, Mohammad Moeen and Homaeinezhad, Mohammad Reza
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DISCRETE-time systems ,DYNAMICAL systems ,MATHEMATICAL optimization ,ACTUATORS ,NONLINEAR systems - Abstract
This paper addresses the control of a nonlinear system affected by deadzone effects, using a constrained actuator. The system itself incorporates a second-order oscillatory dynamic actuator, with an unknown nonlinear input-output relationship. The proposed algorithm not only accommodates the deadzone constraints on control inputs but also considers the actuator's saturation limits in control input calculations. It introduces a trajectory tracking mechanism that, instead of directly following the primary trajectory, adheres to an alternative trajectory capable of stable tracking, gradually converging to the main trajectory while accounting for operational constraints. In practical control systems, the actuator's input-output relationship is often nonlinear and unknown, requiring inversion for model-based control. This paper employs an offline-trained neural network trained on synthetic data to identify and approximate the actuator's behavior. To optimize the control system's performance and ensure stability during sudden error changes, the control input operates in two modes: position and velocity control. This dual-mode control allows for continuous switching between the two, facilitated by an innovative optimization technique based on the gradient descent method with a variable step size. Simulation results validate the effectiveness of the proposed algorithm in controlling systems constrained by hard limits and featuring nonlinear oscillatory actuators, providing a valuable contribution to the field of control systems. • Developing a dual mode non-predictive control algorithm based on discrete-time system equations. • Utilizing an offline-trained neural network for estimating the inverse of the nonlinear actuator relationship. • Stable desired trajectory mapping based on inherent and actuation constraints while maintaining asymptotic stability. • Substituting the trajectory within a fixed range outside of the constant deadzone and inside the variable saturation. • Optimized balancing position and velocity control modes through a weighted average of two control forces. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Carbon nanofibers/chitosan nanocomposite thin film for surface modification of poly(ether sulphone) nanofiltration membrane
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Hosseini, Sayed Mohsen, Moradi, Faezeh, Farahani, Samaneh Koudzari, Bandehali, Samaneh, Parvizian, Fahime, Ebrahimi, Mohammad, and Shen, Jiangnan
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- 2021
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10. Fully coupled thermo-hydro-mechanical approach to model fracture response to injection process in enhanced geothermal systems using displacement discontinuity and finite element method
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Ebrahimi, Mohammad, Ameri, Mohammad Javad, Alizadeh Vaghasloo, Younes, and Sabah, Mohammad
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- 2021
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11. Peripheral nerve regeneration in rats by chitosan/alginate hydrogel composited with Berberine and Naringin nanoparticles: in vitro and in vivo study
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Ebrahimi, Mohammad Hossein, Samadian, Hadi, Davani, Shiva Tavakol, Kolarijani, Nariman Rezaei, Mogharabian, Nasser, Salami, Mohammad Saeid, and Salehi, Majid
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- 2020
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12. Reduced effect of mineral oil toxicity using four-well culture dish in sheep embryo production
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Ebrahimi, Mohammad Reza, Mara, Laura, Parham, Abbas, and Dattena, Maria
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- 2020
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13. Application of unconditional simulation methods for quantifying the uncertainties in mud window design of gas reservoirs based on 3-dimensional mechanical earth modeling
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Ebrahimi, Mohammad Amin, Ahmadi, Mohammad, and Ameri, Mohammad Javad
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- 2020
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14. Application of breakthrough curve analysis and response surface methodology for optimization of a hybrid separation system consisting of fixed-bed column adsorption and dead-end depth filtration
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Askari, Mahdi, Salehi, Ehsan, Ebrahimi, Mohammad, and Barati, Aboulfazl
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- 2019
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15. Detecting and investigating crime by means of data mining: a general crime matching framework
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Keyvanpour, Mohammad Reza, Javideh, Mostafa, and Ebrahimi, Mohammad Reza
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- 2011
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16. Development of rHA1-ELISA for specific and sensitive detection of H9 subtype influenza virus
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Shahsavandi, Shahla, Salmanian, Ali-Hatef, Ghorashi, Seyed Ali, Masoudi, Shahin, Fotouhi, Fatemeh, and Ebrahimi, Mohammad Majid
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- 2011
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17. The distribution of neurotransmitters in the brain circuitry: Mesolimbic pathway and addiction.
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Ebrahimi, Mohammad Navid, Banazadeh, Mohammad, Alitaneh, Zahra, Jaafari Suha, Ali, Esmaeili, Ali, Hasannejad-Asl, Behnam, Siahposht-Khachaki, Ali, Hassanshahi, Amin, and Bagheri-Mohammadi, Saeid
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REWARD (Psychology) , *GABA , *NEURAL circuitry , *TRANSCRANIAL magnetic stimulation , *AMINOBUTYRIC acid - Abstract
• Current paper review the different role of dopamine (DA), glutamate (Glu), and gamma aminobutyric acid (GABA) as reward signals in the context of the mesolimbic circuitry. • While the role of several reward signals such as the DA/Glu/GABA systems, in drug reward, is well known, new research using molecular-based methods has shown functional alterations throughout the reward circuitry that contribute to various aspects of addiction. • A new understanding of the fundamental connections between brain regions as well as the molecular alterations within these particular microcircuits, such as molecular signaling or distinct receptor function, that underlie synaptic and structural plasticity evoked by drugs of abuse has been made possible by the ability to observe and manipulate neuronal activity within specific cell types and circuits. Understanding the central nervous system (CNS) circuitry and its different neurotransmitters that underlie reward is essential to improve treatment for many common health issues, such as addiction. Here, we concentrate on understanding how the mesolimbic circuitry and neurotransmitters are organized and function, and how drug exposure affects synaptic and structural changes in this circuitry. While the role of some reward circuits, like the cerebral dopamine (DA)/glutamate (Glu)/gamma aminobutyric acid (GABA)ergic pathways, in drug reward, is well known, new research using molecular-based methods has shown functional alterations throughout the reward circuitry that contribute to various aspects of addiction, including craving and relapse. A new understanding of the fundamental connections between brain regions as well as the molecular alterations within these particular microcircuits, such as neurotrophic factor and molecular signaling or distinct receptor function, that underlie synaptic and structural plasticity evoked by drugs of abuse has been made possible by the ability to observe and manipulate neuronal activity within specific cell types and circuits. It is exciting that these discoveries from preclinical animal research are now being applied in the clinic, where therapies for human drug dependence, such as deep brain stimulation and transcranial magnetic stimulation, are being tested. Therefore, this chapter seeks to summarize the current understanding of the important brain regions (especially, mesolimbic circuitry) and neurotransmitters implicated in drug-related behaviors and the molecular mechanisms that contribute to altered connectivity between these areas, with the postulation that increased knowledge of the plasticity within the drug reward circuit will lead to new and improved treatments for addiction. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Revolutionary auxetic intravascular medical stents for angioplasty applications.
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Sadegh Ebrahimi, Mohammad, Noruzi, Mohammad, Hamzehei, Ramin, Etemadi, Ehsan, and Hashemi, Ramin
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RIB cage , *ANGIOPLASTY , *FINITE element method , *UNIT cell - Abstract
[Display omitted] • This study proposes novel auxetic medical stents. • Two-dimensional metamaterials were fabricated through additive manufacturing technique. • Finite element analysis was employed to investigate the mechanical behaviour. • An excellent correlation was observed between the FEA and experimental results. • The modifications made to the rib-unit cells had a significant effect on the stent's recoil behaviour. Due to the significant mortality rate associated with atherosclerosis-induced cardiovascular disease, the utilization of advanced intravascular stents with superior mechanical performance is imperative for the restoration of obstructed arteries. This study proposes novel auxetic medical stents that aim to enhance critical parameters of biomedical stents. This includes load-bearing capacity, expanded opening percentage, and reduced recoil percentage. On this matter, the missing rib auxetic unit cell has been considered and geometrically modified to achieve these objectives. Two-dimensional (2D) metamaterials were fabricated through additive manufacturing technique and subjected to experimental testing. Then, finite element analysis (FEA) was employed to gain comprehensive insights into the mechanical behaviour of the proposed medical stents. Remarkably, an excellent correlation was observed between the FEA and experimental results, validating the high precision of the analysis. The findings reveal that the stents classified as "E-category" exhibit the highest final opening percentage while concurrently demonstrating the lowest recoil percentage. The base stent exhibited a relatively high recoil percentage of 15.56%, indicating a significant amount of recoil or spring-back after deformation. In contrast, the modified "E-category" stent displayed a substantially lower recoil percentage of 1.62%. This notable reduction in recoil percentage indicates that the modifications made to the rib-unit cells had a significant and beneficial effect on the stent's recoil behaviour and minimizing potential damage to arterial tissue during stent deployment (angioplasty) and balloon pressure. The modified design likely enhances the stent's ability to maintain its shape and resist recoil, making it more effective and reliable in its intended application. Additionally, more aspects of biomedical stents such as foreshortening, and dog-boning of the modified missing rib stents were meticulously examined through FEA. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Adaptive robust optimization framework for day-ahead microgrid scheduling.
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Ebrahimi, Mohammad Reza and Amjady, Nima
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MICROGRIDS , *ROBUST optimization , *ELECTRIC power distribution scheduling , *WIND power , *SOLAR energy , *TURBINE generators , *POWER distribution networks , *DISTRIBUTED power generation - Abstract
Highlights • Day-ahead microgrid scheduling is modeled in this paper. • The uncertainties are modeled by robust optimization with recourse approach. • Test results of the proposed method on 69 bus distribution system are presented. • Superiority of the proposed method compared with deterministic method is shown. Abstract This paper proposes a framework to address day-ahead scheduling of a microgrid (MG) with wind, solar and micro-turbine distributed generators as well as batteries, considering the associated uncertainties and AC power flow constraints. The problem uncertainties are wind and solar generations, demand, and grid electricity price. The uncertainties are modelled using bounded intervals within adaptive robust optimization method. Unlike previous robust models presented for MG scheduling, our proposed adaptive robust model optimizes both wait-and-see and here-and-now decisions simultaneously which leads to obtaining a better operating point. In order to make wait-and-see and here-and-now decisions and immunize the model against worst case realizations, the proposed MG scheduling model has been formulated as a tri-level optimization framework. In the first level, here-and-now commitment decisions are made (these are decisions made before realization of uncertainties). In the second stage, the worst case realization of the uncertain parameters is determined. In the third level, the wait-and-see recourse decisions are made (these are decisions made after realization of uncertainties). Since there are before uncertainty-realization decisions, worst uncertainty-realization determination, and after uncertainty-realization decisions, the proposed model becomes a tri-level optimization framework. The proposed adaptive robust tri-level MG scheduling model, the proposed solution approach including AdptRob and ConvAC problems, and the proposed out-of-sample analysis are the main contributions of this paper. A convexified AC power flow model is used in the proposed framework for modeling the distribution network. The 69-bus distribution test system is used to test the proposed adaptive robust model as well as the proposed solution approach which converges very fast. Moreover, the results of the out-of-sample analysis shows that the proposed adaptive robust model results in lower expected cost and lower cost variance. [ABSTRACT FROM AUTHOR]
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- 2019
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20. Optimal sparse linear array design with reduced mutual coupling effect.
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Ebrahimi, Mohammad, Karimi, Mahmood, and Modarres-Hashemi, Mahmoud
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OPTIMIZATION algorithms , *DEGREES of freedom , *LINEAR programming - Abstract
Sparse linear arrays (SLAs) provide a high number of degrees of freedom (DOF) and reduce the mutual coupling effect between sensors of the array. Many design methods for SLAs have been proposed in the last two decades but most of the existing SLA design methods fail to achieve minimum number of sensors for a desired DOF. In this paper, a design method is proposed which utilizes the branch and bound (B & B) optimization algorithm to give a SLA with the desired DOF and minimum number of physical sensors. The proposed SLA design method is obtained by generalizing the minimum sensor array (MSA) design method which is recently proposed in the literature. This generalized method provides the same DOF as the MSA method but with a smaller number of physical sensors. In addition, a version of this design method is proposed which provides more robustness against mutual coupling effect between the sensors of the array. Simulation results demonstrate the superiority of the performance of the SLAs obtained with the proposed method over the arrays obtained with the MSA method and also over the other existing SLAs. [ABSTRACT FROM AUTHOR]
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- 2023
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21. Negative differential resistance effect and current rectification in WS2 nanotubes: A density functional theory study.
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Ebrahimi, Mohammad Acef, Ahmadi, Somaieh, Molla, Abdus Salam Sepahi, and Maiti, Santanu K.
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DENSITY functional theory , *GREEN'S functions , *BAND gaps , *NANOTUBES - Abstract
Electronic properties of (n,0) zigzag tungsten disulfide WS 2 nanotubes and transport properties of (7,0) zigzag nanotube heterojunction are investigated by utilizing non-equilibrium Green's function formalism (NEGF). The results reveal that inclusion of the spin-orbit (SO) coupling significantly reduces the value of the band gap about 15.52\%. Additionally, strong negative differential resistances take place in voltage regions between −0.2 and −0.4 V as well as between −0.5 and −0.6 V. Moreover, temperature dependent transport properties are elaborately investigated in this work. The results show that, as the temperature increases to 600 K the stronger negative differential resistance occurs in both positive and negative bias voltages. Finally, a reasonably large degree of rectification ratio can be established. Our analysis can provide a comprehensive perspective on the NDR effect and current rectification in WS 2 nanotubes and can be used as a beneficial guide for future designing of novel logical and nanoelectronic and spintronic devices. • All electronic calculations were carried out using ab-initio DFT-NEGF method. • Transport characteristics were discussed with and without SO coupling. • Reduction of band gap and strong NDR were obtained in the percent of SO coupling. • Stronger NDR was occurred by temperature increasing. [ABSTRACT FROM AUTHOR]
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- 2023
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22. Performance of rural cooperatives' production in Iran: Implications for sustainable development.
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Akbari, Mohammad, Sadegh Ebrahimi, Mohammad, Amini, Amir Mozafar, Shahzad, Umer, Janečková, Kristina, Sklenička, Petr, Miceikienė, Astrida, and Azadi, Hossein
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SUSTAINABLE development , *COOPERATIVE societies , *INSURANCE companies , *SATISFACTION , *RURAL development - Abstract
One of the most important dimensions of cooperative systems, which have existed in Iran since 1974, is cooperative rural production enterprises. In this study, the performance of rural production cooperatives in Iran is examined in relation to the social capital components of the members. This study's statistical population consisted of 16,870 members from 41 cooperatives. 217 samples of cooperative members and 98 samples of the cooperative's management and board of directors were selected using the Cochran formula, and questionnaires were filled out for each group. The results showed that from the viewpoint of the members of rural cooperatives, the most important factor in improving the performance of cooperatives was the use of effective extension training (model-extension sites). The results also showed that members' satisfaction and training members of cooperatives can play an important role in improving the performance of cooperatives. The results of this research, while emphasizing the role of education (especially extension activities), can help rural development planners in improving the performance of rural cooperatives in their regions. [Display omitted] • The study identified the impacts of social capitals on the performance of rural production cooperatives. • The most important factor in improving the performance was the use the extension trainings. • Members' satisfaction and training play an important role in improving the performance. • The level of education in production cooperatives has a direct relationship with trust and satisfaction. • Cooperatives do not perform well in the fields of sales, marketing and insurance. [ABSTRACT FROM AUTHOR]
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- 2023
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23. A novel approach to investigation of the pathogenesis of pterygium based on assessment of promoter hyper-methylation and expression profile of CTLA4 gene: A credible report of CTLA4 gene expression in human eye tissue.
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Ebrahimi, Mohammad Essmail, Kordi-Tamandani, Dor Mohammad, and Arish, Mohammed
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PTERYGIUM , *CYTOTOXIC T lymphocyte-associated molecule-4 , *METHYLATION , *GENE expression , *EYE physiology , *OCULAR injuries , *DISEASE prevalence - Abstract
Background Pterygium is the human eye lesion whose prevalence in the general population is estimated about 2%. The disease, in extreme phase, can lead to visual disturbance and eventually causes complete loss of vision due to the lesion growth over the papillary axis. Pterygium invasive tissue is a tumor-like tissue that is initially identified and then is attacked by cytotoxic T cells. Cytotoxic T lymphocyte associated antigen 4 (CTLA4), as a modulator molecule of the adaptive immune system, plays a critical role in maintaining peripheral T cell tolerance by diminishing its responsiveness and increasing its activation threshold. The aim of this study is to investigate the association between some epigenetic changes of the CTLA4 gene, such as promoter methylation and gene expression, and pathogenesis of pterygia. Materials and methods Genomic DNA was extracted from 75 formalin-fixed, paraffin-embedded tissues of pterygia and 70 specimens of normal conjunctiva from eyes without pterygium as the control group, collected from Sistan and Baluchestan population. CTLA4 gene promoter methylation was carried out by methylation-specific PCR technique. The gene expression analysis was done on extracted total RNA from 20 healthy and 23 pterygium tissue samples using Real-Time PCR technique. Results Promoter methylation changes of CTLA4 gene were not statistically different in patients with pterygium in comparison with healthy controls (OR = 1.614; 95% CI = 0.57–4.75; P value = 0.37). However, gene expression level of CTLA4 was remarkably different in patients and healthy controls (Mean ± SD: 1.343 ± 0.133 and 2.027 ± 0.219, respectively; P value = 0.009). Conclusion This is a credible evidence of CTLA4 gene expression in human eye tissue. This first hand attempt of investigating the association of epigenetic changes of the CTLA4 gene and pathogenesis of pterygia, indicated a significant intensification of the gene expression of CTLA4 in patients with pterygia. We suggest that increasing CTLA4 gene expression can be a trigger which promotes pterygium enlargement. However, further studies on more populations with larger sample sizes need to be done to verify this hypothesis in the future. [ABSTRACT FROM AUTHOR]
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- 2016
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24. Applying memory polynomial model to linearize wideband multi-bit delta-sigma based transmitters
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Ebrahimi, Mohammad Mojtaba, Bassam, S. Aidin, Helaoui, Mohamed, and Ghannouchi, Fadhel M.
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BROADBAND communication systems , *POLYNOMIALS , *RADIO transmitters & transmission , *ELECTRIC distortion , *ELECTRONIC modulators , *ROBUST control , *SIGNAL processing , *SIGNAL-to-noise ratio - Abstract
Abstract: This paper presents a new predistortion linearization technique based on the memory polynomial model of the power amplifier (PA) and a multi-bit delta-sigma modulator (DSM), in order to avoid reverse modeling and the associated instability problems. In this topology, a multi-bit DSM is utilized as a digital predistorter by locating the forward model of the PA in its feedback path. The technique has two main advantages. First, it applies the forward model instead of the reverse model of the PA, which leads to less implementation complexity and, therefore, greater robustness against instability. Second, using a dynamic model instead of a static model makes it more applicable for the linearization of wideband signals, due to the compensation for memory effects. To justify its advantages, linearizers based on both static and dynamic models have been designed and tested. For a 4MHz WiMAX signal, the measurement results show an improvement of 17.2dB in the signal-to-noise and distortion ratio (SNDR) by using a dynamic polynomial model, compared to an improvement of 13dB for a static model. [Copyright &y& Elsevier]
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- 2012
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25. Multi-Objective Optimization of aluminum hollow tubes for vehicle crash energy absorption using a genetic algorithm and neural networks
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Marzbanrad, Javad and Ebrahimi, Mohammad Reza
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AXIAL loads , *ARTIFICIAL neural networks , *GENETIC algorithms , *MATHEMATICAL optimization , *ALUMINUM tubes , *THIN-walled structures , *TRAFFIC accidents - Abstract
Abstract: A numerical study of the crushing of thin-walled circular aluminum tubes has been carried out to investigate their behaviors under axial impact loading. These kinds of tubes are usually used in automobile and train structures to absorb the impact energy. A Multi-Objective Optimization of circular aluminum tubes undergoing axial compressive loading for vehicle crash energy absorption is performed for five crushing parameters using the weighted summation method. To improve the accuracy of the optimization process, artificial neural networks are used to reproduce the behavior of the crushing parameters in crush dynamics conditions. An explicit finite element method (FEM) is used to model and analyzed the behavior. A series of aluminum cylindrical tubes are simulated under axial impact condition for the experimental validation of the numerical solutions. A finite element code, capable of evaluating parameters crush, is prepared of which the outputs are used for training and testing the developed neural networks. In order to find the optimal solution, a genetic algorithm is implemented. With the purpose of illustrating optimum dimensional ratios, numerical results are presented for thin-walled circular aluminum AA6060-T5 and AA6060-T4 tubes. Multi-Objective Optimization of circular aluminum tubes has been performed in the basis of different priorities to create the ability for designer to select the optimum dimension ratio. Also, crush parameters of two aluminum alloys has been compared. [Copyright &y& Elsevier]
- Published
- 2011
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26. Detection of stator winding faults in induction motors using three-phase current monitoring.
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Sharifi, Rasool and Ebrahimi, Mohammad
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FAULT location (Engineering) ,COMPRESSOR blades ,MONITORING of machinery ,WINDING machines ,ELECTRIC potential ,MOTORS ,DETECTORS ,ELECTRICAL harmonics ,ELECTRIC balances - Abstract
Abstract: The objective of this paper is to propose a new method for the detection of inter-turn short circuits in the stator windings of induction motors. In the previous reported methods, the supply voltage unbalance was the major difficulty, and this was solved mostly based on the sequence component impedance or current which are difficult to implement. Some other methods essentially are included in the offline methods. The proposed method is based on the motor current signature analysis and utilizes three phase current spectra to overcome the mentioned problem. Simulation results indicate that under healthy conditions, the rotor slot harmonics have the same magnitude in three phase currents, while under even 1 turn (0.3%) short circuit condition they differ from each other. Although the magnitude of these harmonics depends on the level of unbalanced voltage, they have the same magnitude in three phases in these conditions. Experiments performed under various load, fault, and supply voltage conditions validate the simulation results and demonstrate the effectiveness of the proposed technique. It is shown that the detection of resistive slight short circuits, without sensitivity to supply voltage unbalance is possible. [Copyright &y& Elsevier]
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- 2011
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27. A case study of a patient with diabetic retinopathy.
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Ebrahimi, Mohammad Hossein and Gharibi, Hamed
- Abstract
Summary The patient, in this report, is a 52 years old male driver who had been diagnosed with type 2 diabetes mellitus (T2DM) five years ago without diabetic retinopathy at the baseline. The patient was being monitored for two intervals. It was at the second interval which he was diagnosed with proliferative retinopathy; in fact, the progression rate of retinopathy from its first sign, which occurred at the middle of the first and second interval, to the point at which the patient lost his vision from the left eye occurred within a year. In this work, we introduce a new factor ignored through all the previously conducted studies, namely, type of profession. This factor which contributes to occupational stress plays an important role in the progression of proliferative retinopathy. We speculate that this factor can accelerate the progression of this disease dramatically, even when the other risk factors are not present. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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28. Fully coupled thermo-hydro-mechanical approach to model fracture response to injection process in enhanced geothermal systems using displacement discontinuity and finite element method.
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Ebrahimi, Mohammad, Ameri, Mohammad Javad, Alizadeh Vaghasloo, Younes, and Sabah, Mohammad
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FINITE element method , *INDUCED seismicity , *FLUID injection , *SPATIOTEMPORAL processes , *HYDRAULIC fracturing - Abstract
Assessing, predicting, and controlling injection-induced seismicity is a major challenge for developing enhanced geothermal systems (EGS) due to the complexity of coupled thermo-hydro-mechanical (THM) processes. This study aimed to develop a fully coupled numerical model to assess the complex behavior of a low permeable matrix-fracture during non-isothermal single-phase fluid injection process. A thermo-poroelastic displacement discontinuity (DD) method combining with different forms of finite element method are implemented to encapsulate the fractured medium response and transport processes, respectively. The nonlinear characteristics of normal (changing the joint to hydraulic fracture status) and shear (changing the stick to slip fracture status) fracture deformation are taken into account through fracture constitutive relations. Developed numerical approach was applied to simulate cool water injection into fracture/matrix systems, analyzing the role of coupled processes on spatiotemporal variation of matrix-fracture stresses, temperature and pore pressure and assessing induced seismicity (slippage) and permeability alteration. Numerical simulations demonstrate a fully coupled relation between matrix dilation, shrinkage, and non-linear fracture deformation. The redistribution of dynamic and kinematic parameters along with non-linear fracture deformation showed that although the poroelastic effects are dominant in the early stages, thermoelastic effects dominate in the long-term injection stages. • A fully-coupled Thermo-Hydro-Mechanical approach was developed to model injection process in EGS. • Displacement discontinuity and finite element methods were combined to encapsulate fracture deformation and transport processes, respectively. • Fracture constitutive laws were implemented to model non-linear crack deformation. • Poroelastic effects are dominant in the early stages, and thermoelastic effects dominate in the long-term injection stages. [ABSTRACT FROM AUTHOR]
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- 2022
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29. Hybrid PSO enhanced ANN model and central composite design for modelling and optimization of Low-Intensity magnetic separation of hematite.
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Ebrahimi, Mohammad, Azimi, Ebrahim, Nasiri Sarvi, Mehdi, and Azimi, Yousef
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HEMATITE , *MAGNETIC separation , *PARTICLE swarm optimization , *INDUCTIVE effect - Abstract
• Effect of key parameters on LIDM hematite beneficiation was determined. • Evolving MLPs' architecture was successfully optimized by PSO. • DOE-RSM and PSO-MLP neural network, successfully modelled LIDM separation. • PSO-MLP model out-performed DOE model in predicting product Fe content and SE. • Optimization of the operating parameters led to the product Fe = 60.1% and SE = 36.1% The low intensity dry magnetic beneficiation of hematite was studied in this study, and the effect of field intensity (FI: 800–2000 G), drum speed (DS: 25–75 rpm), separating gate position (SG: 55–83°), and mean particle size (PS: 0.5–1.18 mm) on the products' Fe content and system separation efficiency were determined. A new hybrid particle swarm optimization enhanced multilayer perceptron (PSO-MLP) neural network and design of experiment have been employed to model and predict such a beneficiation result. Based on the CCD-RSM response surfaces, the effectiveness of variables on both evaluation criteria was determined to be DS > FI > SG. The mutual interaction between DS-SG was a common interaction for both responses, while FI-DS interaction was found to be significant only for separation efficiency. Compared to the desired levels of the statistical evaluators, the trained PSO-MLP outperformed the CCD-RSM model in predicting the hematite beneficiation results. Product Fe grade of 60.1% and corresponding SE of 36.1% was achieved for FI = 1200 G, DS = 75 rpm, SG = 83°, and PS = 0.5 mm, concluded from optimizing the parameters. [ABSTRACT FROM AUTHOR]
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- 2021
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30. Determination of the most effective control methods of SO2 Pollution in Tehran based on adaptive neuro-fuzzy inference system.
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Ebrahimi, Mohammad and Qaderi, Farhad
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FUZZY systems , *VORONOI polygons , *GASOLINE , *AIR pollution control , *FUZZY neural networks , *STANDARD deviations , *SULFUR dioxide - Abstract
Air pollution in metropolises is one of the serious problems of human life. Tehran is one of the cities facing air pollution problem. Urban managers concern about choosing different management methods to control air pollution. In this study, a combination of fuzzy systems and neural networks has been used to select the most suitable scenario for controlling SO 2 pollution. According to the method presented in this paper, 8 input data categories such as wind speed, precipitation, temperature, pressure, humidity, gas oil consumption, gasoline consumption and urban green space levels have been used as independent parameters and SO 2 pollutant concentration has been considered as the dependent parameter. The contribution of each meteorological station to the meteorological data was determined by Thiessen Polygon Method. Then, using adaptive neural fuzzy inference systems, modeling was done in Sugeno Method and the least root mean square error (3.19) was determined for the model. Then, by changing each of the independent parameters, the effect of each of these independent parameters on SO 2 pollutant was measured. The results showed that the parameters of pressure, urban green space, gasoline consumption, gas oil consumption, temperature, wind speed and humidity, respectively, had the greatest effect on reducing the SO 2 concentration. Since the parameters of gasoline and gas oil consumption as well as the area of green space are changeable by different policies and by human decisions, the concentration of SO 2 pollutant can be controlled by reducing the consumption of gasoline and gas oil and increasing the green space in Tehran. • Finding the lowest error rate in any of the models predicting sulfur dioxide concentration. • Determine the effect of each of the independent parameters on the concentration of SO 2. • Determination of the best predictive model for sulfur dioxide emissions based on ANFIS model. • Providing solutions to improve air pollution. [ABSTRACT FROM AUTHOR]
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- 2021
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31. The effects of alone and combination tamoxifen, raloxifene and estrogen on lipid profile and atherogenic index of ovariectomized type 2 diabetic rats.
- Author
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Ebrahimi, Mohammad Navid, Khaksari, Mohammad, Sepehri, Gholamreza, Karam, Gholamreza Asadi, Raji-amirhasani, Alireza, and Azizian, Hossein
- Subjects
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SELECTIVE estrogen receptor modulators , *RALOXIFENE , *STREPTOZOTOCIN , *TAMOXIFEN , *PEOPLE with diabetes , *TYPE 2 diabetes - Abstract
The cardiovascular dysfunctions in postmenopausal diabetic women increase relative to premenopausal women. In this study we evaluated protective effects of selective estrogen receptor modulators (SERMs), alone and in combination with estrogen (E2) in diabetic rats with menopausal model. Female rats groups are included: Sham-Control (CTL), Diabetes (DM), and ovariectomized rats divided to DM, DM + Vehicle (Veh), DM + Tamoxifen (TAM), DM + Raloxifene (RLX), DM + Veh + Oil, DM + Oil, DM + E2, DM + E2 + Veh, DM + TAM + E2, DM + RLX + E2. DM was induced by high fat diet and followed by a light dose of streptozotocin. SERMs and E2 were administrated for four weeks after establishment of type 2 diabetes mellitus (T2DM). Our results depicts that, T2DM increased triglyceride, total cholesterol, low-density lipoprotein, and fasting blood glucose. Also it decreased high-density lipoprotein, which had exacerbated by ovariectomy. These changes were reversed by using SERMs, E2 and SERMs+E2, although combinatory treatment is more effective than individual treatment. Additionally the cardiovascular indices were also significantly disrupted in ovariectomized diabetic rats, but all therapeutic groups equally improved these disturbances, whereas in TAM + E2 group, the atherogenic index was more decreased than TAM group. We concluded that SERMs treatment, individual or in combination with E2 in menopausal model can be efficient substitute for E2 replacement therapy. This study suggests cellular mechanisms of SERMs in future studies. [ABSTRACT FROM AUTHOR]
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- 2020
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32. Regulation of drought-related responses in tomato plants by two classes of calcineurin B-like (SlCBL1/2) proteins.
- Author
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Hosseini Tafreshi, Seyed Ali, Aghaie, Peyman, Ebrahimi, Mohammad Ali, and Haerinasab, Maryam
- Subjects
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CALCINEURIN , *PLANT life cycles , *DROUGHT tolerance , *TOMATOES , *GENE silencing , *GENES - Abstract
Calcineurin-B-like proteins (CBLs) are essential components of the calcium signaling network and act during plant's response to stress and normal conditions. A combined research strategy of in-silico analysis and gene silencing experiment was employed to investigate the role of different classes of CBLs in tomato (Solanum lycopersicum L.) during the response to drought stress. Two different classes of CBL genes, including SlCBL3-1 , and SlCBL3-2 , with the minimum and a maximum number of drought-responsive cis-elements, were selected and were targeted for transient gene silencing in tomato followed by the drought treatment. The effect of silencing events was evaluated by determining of further growth and physiological traits in plants under both control and drought stress conditions. The results showed that silencing of SlCBL3-1 significantly reduced shoot and root growth, relative water content (RWC), and the concentration of pigments while increased free radical accumulation, lipid peroxidation, and leakage from the cells. On the other hand, no antioxidant enzyme activity or proline induction was triggered in plants after SlCBL3-1 silencing. Some of these adverse events were more significantly enhanced when the silenced plants were exposed to drought stress. Overall, a significant role for SlCBL3-1 in the life cycle of plant suggested under both normal and stress conditions. The SlCBL3-2 silencing showed more efficient plants recovery from silencing or drought stress conditions. Therefore, SlCBL3-2 gene may act as a negative regulator under stress conditions. The results might provide new theoretical insight and genetic resources for developing resistant crops against environmental stresses. • Different classes of Calcineurin B-like (CBL) proteins regulate the plant responses during normal or stress conditions. • SlCBL3-1 plays a critical role in maintaining hemostasis in life cycle of plants under both normal and stress conditions. • SlCBL3-2 that is another class of CBL may act as a negative regulator under stress conditions. • A low copy number of cis-element in the promoter of CBL gene is sufficient to trigger a proper stress-induced response. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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33. Prevalence of metabolic syndrome among Iranian occupational drivers.
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Ebrahimi, Mohammad Hossein, Delvarianzadeh, Mehri, and Saadat, Saeed
- Abstract
Aims Compared with other members of a society, drivers are under more periodic and constant surveillance due mainly to this fact that their type of work requires them to spend most of their times in a sedentarily position. The recent survey had done to evaluate the prevalence of Met Syn among professional drivers in northeast area of Iran. Materials and methods To evaluate the prevalence of Met Syn among long-haul drivers, 1018 male drivers were studied. Definition of Met Syn was based on ATP III, IDF and AHA. The statistical tests were composed of chi-square and independent t tests. Results and conclusion The participants’ mean age was 42.17 ± 10.65 years. The prevalence of Met Syn according to ATP III, IDF and AHA criteria was 26.1%, 35.2% and 31.6% respectively. 6.6% of drivers were impaired fasting glucose. The drivers with the bus, minibus, taxi formed the greatest number of smokers (82.9%) among all drivers ( p = 0.023). The average of body mass index (BMI) was 26.2 ± 4.06. The most prevalence of Mets according to IDF criteria were observed in drivers of heavy vehicles and also the ones of passenger vehicles, with 36.7% and 43.9% respectively. Based on high prevalence of Met Syn and other risk factors in this study, and considering these factors, should be more careful about this point. It is recommended to control risk factors such as, control of high BMI and TG, LDL, waist circumfernce, education. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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34. Tolerance evaluation and clustering of fourteen tomato cultivars grown under mild and severe drought conditions.
- Author
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Aghaie, Peyman, Hosseini Tafreshi, Seyed Ali, Ebrahimi, Mohammad Ali, and Haerinasab, Maryam
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TOMATO varieties , *CROPS , *DROUGHT tolerance , *MALONDIALDEHYDE , *SUPEROXIDE dismutase , *PRINCIPAL components analysis - Abstract
The growth and physiological parameters of fourteen tomato cultivars were measured during both mild and severe drought. The tomato cultivars showed decrease in growth traits, relative water content and pigments content under both drought treatments compared with the control. By contrast, proline accumulation, malondialdehyde and electrolyte leakage increased in the cultivars. The activity of superoxide dismutase was more correlated to drought stress than those of ascorbate peroxidase or catalase. The combined approach of principal component analysis, hierarchical clustering analysis and calculating mean tolerance value showed relative differences in drought tolerance among the cultivars. The studied cultivars were clustered into four groups. Four cultivars were placed in cluster I as the drought-tolerant group. Moderately tolerant cultivars were grouped into Cluster II. The clusters III and IV represented the sensitive and highly sensitive cultivars, respectively. Early orbana, Roma and Cal-j cultivars were indicated as the highly sensitive tomato cultivars. It was concluded that such an approach could be used as a useful tool to screen the other abiotic or even biotic stress tolerance in tomato. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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35. Evaluation of the magnitude of hip joint deformation in subjects with avascular necrosis of the hip joint during walking with and without Scottish Rite orthosis.
- Author
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Karimi, Mohammad Taghi, Mohammadi, Ali, Ebrahimi, Mohammad Hossein, and McGarry, Anthony
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NECROSIS , *HIP joint , *BONE density , *MOTION capture (Human mechanics) , *ORTHOPEDIC apparatus , *THERAPEUTICS - Abstract
The femoral head in subjects with leg calve perthes disease (LCPD) is generally considerably deformed. It is debatable whether this deformation is due to an increase in applied loads, a decrease in bone mineral density or a change in containment of articular surfaces. The aim of this study was to determine the influence of these factors on deformation of the femoral head. Two subjects with LCPD participated in this study. Subject motion and the forces applied on the affected leg were recorded using a motion analysis system ( Qualsis TM ) and a Kistler force plate. OpenSim software was used to determine joint contact force of the hip joint whilst walking with and without a Scottish Rite orthosis. 3D Models of hip joints of both subjects were produced by Mimics software . The deformation of femoral bone was determined by Abaqus . Mean values of the force applied on the leg increased while walking with the orthosis. There was no difference between bone mineral density (BMD) of the femoral bone of normal and LCPD sides ( p -value>0.05) and no difference between hip joint contact force of normal and LCPD sides. Hip joint containment appeared to decrease follow the use of the orthosis. It can be concluded that the deformation of femoral head in LCPD may not be due to change in BMD or applied load. Although the Scottish Rite orthosis is used mostly to increase hip joint containment, it appears to reduce hip joint contact area. It is recommended that a similar study is conducted using a higher number of subjects. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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36. The effect of Brucella abortus on glial activation and cell death in adult male rat's hippocampus.
- Author
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Fathi, Mobina, Vakili, Kimia, Mohammadzadeh, Ibrahim, Sani, Mojtaba, Khakpour, Yaser, Azimi, Helia, Norouzian, Mohsen, Moghaddam, Meysam Hassani, Khodagholi, Fariba, Sadrinasab, Shayan, Gilavand, Helia Karami, Ebrahimi, Mohammad Javad, Moafi, Maral, Beirami, Amirreza, Hasanzadeh, Maral, Bahar, Reza, Bayat, Amir‑Hossein, Alamian, Saeed, and Aliaghaei, Abbas
- Abstract
A zoonotic disease called brucellosis can cause flu-like symptoms and heart inflammation. The bacteria responsible for this disease can also enter the brain, causing a condition called neurobrucellosis that can result in long-term neurological problems. In this study, researchers aimed to determine the changes in the hippocampal cells of rats infected with Brucella. For the study, 24 adult male albino rats were inoculated with 1 × 106 CFU Brucella abortus 544. The rats were then deeply anesthetized, and their hippocampus samples were taken for stereological, histological, and molecular studies. The results showed that the infected rats had increased microgliosis and astrogliosis. Furthermore, a high level of caspase-3 in their hippocampal tissue indicated their susceptibility to apoptosis. Additionally, there was a decrease in expression of Ki67, which further supported this. Sholl's analysis confirmed a significant failure in glial morphology. The study demonstrated that the pathogen has the ability to destroy the hippocampus and potentially affect its normal physiology. However, more research is needed to clarify various aspects of neurobrucellosis. • Brucella increases astrogliosis and changes the morphological characteristics of astrocytes in the hippocampus. • Brucella Increases microgliosis in rats' hippocampus and alters microglia cells' morphological characteristics. • Brucella infection induces the expression of caspase-3 in Pyramidal cells and reduces neurogenesis in the hippocampus. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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37. On application of high-order compact finite-difference schemes to compressible vorticity confinement method.
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Sadri, Maryam, Hejranfar, Kazem, and Ebrahimi, Mohammad
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FINITE difference method , *VORTEX motion , *DIFFERENTIAL equations , *EULER equations , *DISCRETIZATION methods - Abstract
The main goal of this study is to assess the application of high-order compact finite-difference schemes for the solution of the Euler equations in conjunction with the compressible vorticity confinement method on both uniform Cartesian and curvilinear grids. Here, the spatial discretization of the governing equations is performed by the fourth-order compact finite-difference scheme and the temporal term is discretized by the fourth-order Runge–Kutta method. To stabilize the numerical solution, appropriate dissipation terms are applied and a detail assessment is performed to study the effects of the values of confinement and dissipation coefficients on the solution to reasonably preserve the structure of vortical flows. The accuracy and performance of the proposed solution procedure by applying the fourth-order compact finite-difference scheme are also examined by comparison with the solution obtained by the second-order central finite-difference scheme. Low-pass high-order filters are also applied to the fourth-order compact finite-difference scheme to investigate the performance of the vorticity confinement with the filtering scheme. The advection of a 2D isentropic vortex and a shock–vortex interaction problem are two test cases simulated for the assessment of the present solution methodology. The study shows that the high-order compact finite-difference schemes in conjunction with the vorticity confinement method can reasonably preserve the structure of vortical flows in coarse uniform Cartesian and curvilinear grids. Indications are that the present solution methodology is accurate and effective for solving compressible flow problems with vortical structures when coarse grids are used. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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38. Biosensors for detection of Tau protein as an Alzheimer's disease marker.
- Author
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Ameri, Mehrdad, Shabaninejad, Zahra, Movahedpour, Ahmad, Sahebkar, Amirhossein, Mohammadi, Soheila, Hosseindoost, Saereh, Ebrahimi, Mohammad Saeid, Savardashtaki, Amir, Karimipour, Mohammad, and Mirzaei, Hamed
- Subjects
- *
TAU proteins , *ALZHEIMER'S disease , *TUBULINS , *BIOSENSORS , *NUCLEIC acids , *NEUROFIBRILLARY tangles , *CEREBROSPINAL fluid , *NEURODEGENERATION - Abstract
Known as a main neural MAP (microtubule associated protein), tau protein contributes to stabilizing microtubules involved in cellular transmission. Tau dysfunction is mainly associated with neurodegenerative diseases, particularly Alzheimer's disease (AD). In these patients, all the six tau isoforms, which are in hyperphosphorylated form, are first aggregated and then polymerized into neurofibrillary tangles inside the brain. Tau protein detected in cerebrospinal fluid (CSF) is significantly correlated with AD and is well recognized as a hallmark of the disease. Served for detection of analytes of interest, biosensor device comprises a physical transducer and a keen biological recognition component. Qualitative and quantitative evaluations may be performed through analyzation of the data, which is gathered by measurable signals converted from biological reaction. Antibodies, receptors, microorganisms, nucleic acids, enzymes, cells and tissues, as well as some biomimetic structures, normally constitute the biosensor biological recognition part. Production of nanobiosensor, which was made possible through several accomplishments in nano- and fabrication technology, opens up new biotechnological horizons in diagnosis of multiple diseases. In recent years, many researches have been focused on developing novel and effective tau protein biosensors for rapid and accurate detection of AD. In this review, tau protein function and correlation with AD as well as the eminent research on developing nanobiosensor based on optical, electrochemical and piezoelectric approaches will be highlighted. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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39. Integration of molecular and geographical data analysis of Iranian Prunus scoparia populations in order to assess genetic diversity and conservation planning.
- Author
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Zeinalabedini, Mehrshad, Majidian, Parastoo, Ashori, Reyhaneh, Gholaminejad, Ameneh, Ebrahimi, Mohammad Ali, and Martinez-Gomez, Pedro
- Subjects
- *
PRUNUS , *PLANT genetics , *PLANT conservation , *PLANT germplasm , *GEOGRAPHIC information systems - Abstract
Highlights • Variation analysis of Prunus scoparia by molecular marker. Abstract Evaluation of spatial and non-spatial distribution is of great importance for protection of plant's genetic resources. Prunus scoparia , a wild almond species, is an important economically and ecologically food resource plant in Iran with specific characteristics such as self-compatibility, resistant to drought and fungus, bitterness as well as small nuts. This wild species can provide an enlarged gene pool and may be considered as a valuable germplasm source for breeding the cultivated almond. In this study, the conservation planning and genetic variation of 158 Prunus scoparia accessions was investigated with the aid of 36 SSR markers to reveal genetic distinctness and structure. The molecular markers studied showed quite high level of genetic diversity on the basis of N a = 6.47, H o = 0.603 and H e = 0.737. The result of Neighbor net analysis was not in parallel with STRUCTURE data as classified samples into two and 12 main groups, respectively. On the other hand, the results of GENELAND analysis ensured the population classification and the genetic relatedness between populations from STRUCTURE analysis due to use of geographical data. All samples were grouped based on their geographical location. Moreover, utilization of GIS data accompanied by appropriate number of SSR markers could provide the possibility of prioritizing of distribution regions in natural and unnatural environments. The species distribution modeling would also help gain comprehensive information on conservation strategies of this wild almond species. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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40. Numerical modeling of injection-induced earthquakes based on fully coupled thermo-poroelastic boundary element method.
- Author
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Sabah, Mohammad, Ameri, Mohammad Javad, Hofmann, Hannes, and Ebrahimi, Mohammad
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- *
BOUNDARY element methods , *FLUID injection , *INDUCED seismicity , *ATMOSPHERIC pressure , *FINITE element method - Abstract
• A fully-coupled Thermo-Hydro-Mechanical approach was developed to study injection-induced seismicity and permeability enhancement in low permeable reservoirs. • Fracture deformation and transport processes were modeled using thermo-poroelastic displacement discontinuity method combined with Galerkin and Petrov Galerkin finite element methods. • Constitutive behavior of fault friction was captured using rate-and-state friction model incorporating aging law for history of sliding. • Traffic Light System-based injection protocols yield higher potential in enhancing the fault permeability. • Volume-Controlled fluid injection are far more effective in reducing the seismic risk. In recent years, there has been a substantial increase in the induced seismicity associated with geothermal systems. However, understanding and modeling of injection-induced seismicity have still remained as a challenge. This paper presents a two-dimensional fully thermo-hydro-mechanical (THM) coupled boundary element approach to characterize the fault response to forced fluid injection and assess the effect of different injection protocols on seismic risk mitigation as well as permeability enhancement. The laboratory-derived rate-and-state friction law was used to capture the frictional paradigm observed in mature faults produced in granite rocks. All phases of stick-slip cycles, including aseismic slip, propagation of dynamic rupture, and interseismic periods, were simulated. The modeling results showed that the residual values of effective normal stress and static shear stress after a particular event completely dominate the constitutive behavior of fault friction during the next seismic event. The seismic energy analyses indicated that there is a negative correlation between the seismic magnitude and the total injected volume, such that a prolonged monotonic injection eventually results in the steady slip, rather than the seismic slip. Several fluid injection protocols were designed based on a volume-controlled (VC) approach and traffic light systems (TLS) to explore their effectiveness on the seismic risk mitigation and permeability enhancement. The results showed that cyclic injection based on TLS is the most effective approach for irreversible permeability enhancement of faults through promoting slow and steady slips. Our numerical simulations also revealed that fluid extraction (backflow-fixing bottom hole pressure at atmospheric pressure), regardless of the injection style, can considerably reduce the seismicity-related risks by preventing the fast-accelerated fracture slip during the post-injection stage. This study presents novel insights into modeling the rate-and-state governed faults exposed to forced fluid injection, and provides useful approaches for shear stimulation of faults with reduced seismic risks. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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41. Protective effects of combining SERMs with estrogen on metabolic parameters in postmenopausal diabetic cardiovascular dysfunction: The role of cytokines and angiotensin II.
- Author
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Khaksari, Mohammad, Raji-Amirhasani, Alireza, Bashiri, Hamideh, Ebrahimi, Mohammad Navid, and Azizian, Hossein
- Subjects
- *
CARDIOVASCULAR diseases , *SELECTIVE estrogen receptor modulators , *TYPE 2 diabetes , *ANGIOTENSINS , *ANGIOTENSIN II - Abstract
• Administration of selective estrogen receptor modulators (SERMs) in combination with estrogen (E2), could be an effective in the treatment of menopausal diabetes. • Combined treatments of SERMs and E2 were more effective than the effects of E2 or SERMs alone. • E2 or SERMs have beneficial effects on cardiovascular system by improving inflammatory balance and reducing Ang II levels. The beneficial effects of the administration of selective estrogen receptor modulators (SERMs) and estrogen (E2), alone or in combination with each other, have been reported in postmenopausal diabetic cardiovascular dysfunction. In the present study, we determined the mechanism of action of SERMs and E2 on inflammatory balance, angiotensin II (Ang II) serum levels, and glycemic profile in a postmenopausal diabetic rat model. Ovariectomized rats with type 2 diabetes received daily SERMs (tamoxifen and raloxifene) and E2 for one month. After treatment, cardiovascular risk indices, glycemic profile, and serum Ang II, TNF-α and IL-10 levels were measured. Type 2 diabetes caused an abnormal glycemic profile, which was exacerbated by ovariectomy. All treatments inhibited the effects of diabetes and ovariectomy on the glycemic profile, with combined treatments (SERMs + E2) showing stronger effects. Cardiovascular risk indices that became abnormal by diabetes and worsened by ovariectomy were improved in all treatment modalities. Also, combined treatment reduced serum Ang II, TNF-α, and the ratio of TNF-α to IL-10, indicating an improvement in inflammatory balance. Our study showed the administration of SERMs and E2, alone or in combination, could be an effective alternative in the treatment of menopausal diabetes, and generally, the beneficial effects of combined treatments were more effective than the effects of E2 or SERMs alone. It appears that E2 or SERMs benefit the cardiovascular system by improving inflammatory balance and reducing Ang II levels. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
42. Evaluation of cellular and humoral immune response in chickens immunized with flagellin-adjuvanted inactivated newcastle disease virus.
- Author
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Bagheri, Masoumeh, Khani, Mohammad-Hosein, Zahmatkesh, Azadeh, Barkhordari, Maryam, Ebrahimi, Mohammad Majid, Asli, Esmaeel, Shahsavandi, Shahla, Banihashemi, Seyed Reza, Esmaeilnejad-Ahranjani, Parvaneh, and Moradi Bidhendi, Soheila
- Subjects
- *
HUMORAL immunity , *NEWCASTLE disease virus , *CHICKENS , *ANTIBODY titer , *CELLULAR immunity , *POULTRY breeding - Abstract
The aim of the present study was to evaluate the potential effect of flagellin as adjuvant in Newcastle disease virus (NDV) vaccine on the cellular and humoral immunity in chickens. Fifty-six specific pathogen-free chickens were assigned to seven groups of eight chickens and immunized twice with a two-week interval, intramuscularly. Group 1, received phosphate buffered saline as control (C), groups 2, 3, 4, 5, 6 and 7 were immunized with inactivated NDV [Ag], Ag + full FliC protein [AgF], Ag + truncated Flic protein [AgT], Ag + native Flic protein [AgN], commercial NDV vaccine [Vac] and Vac + N [VacN], respectively. After 45 days, spleen and bursa of Fabricius samples were collected and analyzed by flow cytometry and responses in control/vaccinated chickens were studied by immunophenotyping. Humoral response was also, evaluated by ELISA during the experiment. Results showed that immunized chickens with Ag + flagellin proteins had significantly higher frequency of circulating CD3+, CD4+ and CD8+ T cells in bursa of Fabricius in AgF, AgT and AgN, respectively, compared with other groups. Similar results were observed for spleen; however, the highest frequency of circulating CD3+, CD4+ and CD8+ T cells belonged to AgT and AgF, respectively. ELISA results showed that all flagellin-adjuvanted groups had higher antibody titers than other groups with the highest antibody response in VacN. It can be concluded that flagellin may induce both humoral and cellular immune responses against ND and is suggested for use as an efficient adjuvant. • Flagellin-adjuvanted groups had higher frequency of CD4 and CD8 T cells. • All flagellin-adjuvanted groups had higher antibody titers than other groups. • Native flagellin enhanced antibody response in commercial vaccine. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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43. Extensive genetic diversity in Iranian pomegranate (Punica granatum L.) germplasm revealed by microsatellite markers
- Author
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alamuti, Mehrbanoo Kazemi, Zeinalabedini, Mehrshad, Derazmahalleh, Mahsa Mousavi, RoodbarShojaie, Taha, Irandoost, Hashem Poor, Zahravi, Mehdi, Vazifehshenas, Mohammad, Ebrahimi, Mohammad Ali, Nekouei, Sayed Mojtaba Khayam, Salekdeh, Ghasem Hossini, and Mardi, Mohsen
- Subjects
- *
PLANT diversity , *MICROSATELLITE repeats in plants , *PLANT genetics , *POMEGRANATE , *BIOMARKERS , *GENETIC polymorphisms in plants , *AMINO acid sequence , *PLANT germplasm - Abstract
Abstract: A set of twelve simple sequence repeat markers was used to evaluate the genetic background of 738 pomegranate (Punica granatum L.) accessions, which belonged to the Iranian National Pomegranate Collection, from 23 provinces of Iran. Genetic diversity among the accessions was analysed using several variability parameters. Forty-three alleles were detected with a mean of 3.59 alleles per locus. The highest levels of polymorphism were found for the locus ABRII-MP26. The mean values of expected heterozygosity and polymorphic information content were 0.521 and 0.458, respectively. Neighbour-Net analysis based on uncorrected P distances and a model-based method separated the accessions into 8 main groups and several subgroups, with a tendency to cluster by geographical origin. From the simple sequence repeat analysis, it can be concluded that the genetic base of the Iranian National Pomegranate Collection is broad enough to ensure future progress in breeding programmes and these markers are effective tools for conducting genetic diversity studies in pomegranate and developing strategies for germplasm management. [Copyright &y& Elsevier]
- Published
- 2012
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44. Evolutionary characterization of hemagglutinin gene of H9N2 influenza viruses isolated from Asia
- Author
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Shahsavandi, Shahla, Salmanian, Ali-Hatef, Ghorashi, Seyed Ali, Masoudi, Shahin, and Ebrahimi, Mohammad Majid
- Subjects
- *
HEMAGGLUTININ , *INFLUENZA viruses , *ANIMAL genetics , *PHYLOGENY , *BAYESIAN analysis , *PROTEIN binding - Abstract
Abstract: The full length hemagglutinin (HA) genes of 287 H9N2 AI strains isolated from chickens in Asia during the period 1994–2009 were genetically analyzed. Phylogenetic analysis showed that G1-like viruses circulated in the Middle East and Indian sub-continent countries, whereas other sublineages existed in Far East countries. It also revealed G1-like viruses with an average 96.7% identity clustered into two subgroups largely based on their time of isolation. The Ka/Ks ratio was calculated 0.34 for subgroup 1 and 0.57 for subgroup 2 indicates purifying/stabilizing selection, but despite this there is evidence of localized positive selection when comparing the subgroups 1 and 2 protein sequences. Five sites in HA H9N2 viruses had a posterior probability >0.5 using the Bayesian method, indicating these sites were under positive selection. These sites were found to be associated with the globular head region of HA. To identify sites under positive selection; amino acid substitution classified depends on their radicalism and neutrality. The results indicate that, although most positions in HAs were under purifying selection and can be eliminated, a few positions located in the antigenic regions and receptor binding sites were subject to positive selection. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
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45. Kinetic study of cytokines production by human peripheral blood mononuclear cells in response to Brucella DNA
- Author
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Lashkarbolouki, Taghi, Ardestani, Sussan K., Kariminia, Amina, Ziaee, Abed-Ali, Torkabadi, Ebrahim, and Ebrahimi, Mohammad
- Subjects
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CYTOKINES , *DNA , *ANTINEOPLASTIC agents , *ANTIVIRAL agents - Abstract
Summary: In spite of reports on cytokines induction by the Brucella DNA in murine model, there is no comparison between pathogenic and appropriate vaccine strains in human. We investigated the cytokines profile of human peripheral blood mononuclear cells (PBMCs) induced by DNA extracted from pathogenic isolates of Brucella melitensis and B. abortus as well as Rev1 and S19; the appropriate vaccine strains. It was observed that despite differential induction of Interleukin(IL)-12 and IL-10 production, identical IL-12/IL-10 concentration ratio was obtained by all Brucella strains DNAs that was 2 after 24h and 4 after 5 days of incubation. In addition, IL-2 and Interferon(IFN)-γ production were profoundly increased compared to the medium at day 3 and 5 respectively but IFN-α was not induced. Therefore, Brucella strains DNAs are Th1 inducing component with similar pattern in human PBMCs. [Copyright &y& Elsevier]
- Published
- 2008
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46. Comparison of flagellin and an oil-emulsion adjuvant in inactivated Newcastle disease vaccine in stimulation of immunogenic parameters.
- Author
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Barkhordari, Maryam, Bagheri, Masoumeh, Irian, Saeed, Khani, Mohammad-Hosein, Ebrahimi, Mohammad Majid, Zahmatkesh, Azadeh, and Shahsavandi, Shahla
- Subjects
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NEWCASTLE disease vaccines , *FLAGELLIN , *NEWCASTLE disease virus , *POULTRY breeding , *BACTERIAL inactivation , *CHICKEN diseases , *BLOOD cells , *ANTIBODY formation - Abstract
• The most IL-6 and TNF-α gene expression was observed in full flagellin adjuvanted group. • The recombinant full flagellin adjuvanted group showed the highest cellular activity. • The highest HI titer was observed in commercial vaccine and recombinant flagellin adjuvanted groups. The present study was designed to investigate the potential application of native (N) and recombinant (truncated modified [tmFliC] and full-length [flFliC]) flagellin proteins along with inactivated Newcastle disease virus (NDV). Fifty six SPF chickens were immunized twice with PBS (control), inactivated NDV (Ag), inactivated NDV/flFliC (AgF), inactivated NDV/tmFliC (AgT), inactivated NDV/N (AgN), commercial vaccine containing Montanide (Vac) and Vac/N (VacN), with a two-week interval. Blood was collected weekly and spleens were harvested after chickens were sacrificed. Interleukin-6 (IL-6) and tumor necrotic factor-α (TNF-α) gene expression in peripheral blood mononuclear cells were analyzed by Real-Time PCR. Antibody response was assessed by haemagglutination inhibition (HI). Cellular activity was quantified by MTT assay. Results showed that the most IL-6 and TNF-α gene expression was observed in AgF group (P < 0.01). The lowest gene expression among vaccinated groups was observed in Ag group for IL-6 and Ag and Vac group for TNF-α. The highest HI titer was observed in Vac, VacN, AgF and AgT groups. The AgF group showed the highest cellular activity (P < 0.01). In conclusion, flagellin-adjuvanted groups showed a pro-inflammatory effect and acted similarly to or better than the Vac group. Hence, flagellin can be proposed as a potential adjuvant for ND vaccine. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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47. Chitosan-based nanoparticles against bacterial infections.
- Author
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Rashki, Somaye, Asgarpour, Kasra, Tarrahimofrad, Hossein, Hashemipour, Maryam, Ebrahimi, Mohammad Saeid, Fathizadeh, Hadis, Khorshidi, Ahmad, Khan, Haroon, Marzhoseyni, Zeynab, Salavati-Niasari, Masoud, and Mirzaei, Hamed
- Subjects
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BACTERIAL diseases , *NANOPARTICLES , *BACTERIAL cell walls , *BIODEGRADABLE nanoparticles , *DRUG carriers , *ANTIMICROBIAL bandages , *CHITOSAN , *CELL membranes - Abstract
• Bacterial infections in serious burns have been a constant threat to human health throughout history. • Chitosan has significant antibacterial activity against a broad spectrum of bacteria. • Chitosan nanoparticles could be used as drug carriers and gene carrier to enhance their transfer efficiency in the cells. • Chitosan-based nanomaterials could be used against bacterial infections. Chitosan nanomaterials have become a hot topic in biomedicine due to exerting antimicrobial effects with interestingly high levels of biodegradability and biocompatibility without causing toxicity. Regarded as a potential means of wound dressing with antimicrobial activity, chitosan exhibits higher efficiency when it is functionally modified with other natural compounds, metallic antimicrobial particles and antibiotics. Mechanistically, the antibacterial effect of chitosan is mostly, associated with the death-proceeding leakage of intracellular content, induced by malfunction and altered permeability of the negatively charged cell membrane, on which chitosan is adsorbed. Moreover, chitosan nanoparticles (NPs) are endowed with favorable features of NPs (i.e., large surface-to-volume ratio, high functionalization possibilities and a greater capacity for drug loading), as well as that of their chitosan base, thereby possessing strengthened antibacterial potential. In addition, polycations target negatively charged bacterial membranes, so bacteria cells are more strongly affected by polycationic chitosan NPs than pure chitosan. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
48. Voluntary exercise modulates learning & memory and synaptic plasticity impairments in sleep deprived female rats.
- Author
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Rajizadeh, Mohammad Amin, Esmaeilpour, Khadijeh, Haghparast, Elham, Ebrahimi, Mohammad Navid, and Sheibani, Vahid
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NEUROPLASTICITY , *HIPPOCAMPUS (Brain) , *SLEEP deprivation , *LONG-term potentiation , *EXERCISE , *INTELLIGENCE tests - Abstract
• Sleep deprivation impaired Learning and memory in Barnes and Novel location tasks. • Sleep deprivation disrupted Synaptic plasticity. • Prior voluntary exercise modulated impairments resulting from subsequent SD. Previous studies have indicated that forced exercise plays a preventive role in synaptic plasticity deficits in the hippocampus and behavioral impairments in sleep-deprived male and female rats. The objective of the present study was to evaluate the effects of voluntary exercise on early long-term potentiation (E-LTP) at the Cornu Ammonis (CA1) area of the hippocampus and behavioral functions by barnes maze and novel location tests in sleep-deprived female rats. Intact female Wistar rats were used in the present study. The exercise protocol was four weeks wheel running and the multiple platform method was applied to induce 72 h Sleep deprivation (SD). We examine the effect of exercise and/or SD on synaptic plasticity using in vivo extracellular recording in the CA1 area of the hippocampus. Spatial learning and memory examined by Barnes maze and recognition memory assessed by novel location test. Field potential recording indicated that the induction and maintenance phase of E-LTP impaired in the sleep deprived animals compared to the other groups. After 72 h SD, LTP impairments were reduced by 4 weeks of voluntary exercise but do not go back to control values. SD impairs learning and memory and exercise could improve these deficits. In conclusion, the synaptic plasticity deficit in sleep-deprived female rats was improved by voluntary exercise. Further studies are suggested to evaluate the possible underlying mechanisms. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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49. Attentional bias and its temporal dynamics among war veterans suffering from chronic pain: Investigating the contribution of post-traumatic stress symptoms.
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Mazidi, Mahdi, Vig, Kelsey, Ranjbar, Seyran, Ebrahimi, Mohammad-Reza, and Khatibi, Ali
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ATTENTIONAL bias , *POST-traumatic stress , *CHRONIC pain , *VETERANS , *REACTION time , *FACIAL expression , *SELF-expression - Abstract
• Chronic pain is highly comorbid with PTSD symptoms in war veterans. • Attentional bias in pain is suggested to be relevant to anxiety in chronic pain. • Veterans showed a greater attentional bias away from pain-related cues. • Avoidance from pain may indicate suppression of emotion in stressful situations. • Veterans showed significantly elevated attentional bias variability for both happy and pain faces compared to controls. Cognitive models propose that attentional dysregulation, including an attentional bias towards threat, is one of the factors through which chronic pain and post-traumatic stress symptoms (PTSS) maintain and exacerbate one another. The current investigation assessed the attentional bias for painful facial expressions and its relationship with PTSS, using both traditional and variability-based attentional bias measures, among veterans with chronic pain and PTSS and controls. Fifty-four veterans with chronic pain and 30 age/education-matched controls participated in this investigation. Participants completed a self-report measure of PTSS and a modified version of the dot-probe task with painful, happy, and neutral facial expressions. Attention was assessed using both traditional and variability-based reaction time measures of attentional bias. Veterans directed attention away from painful facial expressions (i.e., avoidance) relative to both the control group (between-subject effect) and relative to neutral faces (within-subject effect). Veterans also showed significantly elevated attentional bias variability for both happy and painful facial expressions compared to controls. Attentional bias variability for happy and painful facial expressions was correlated with PTSS among all participants. Veterans with chronic pain and PTSS avoided pain-related stimuli and displayed an overall attentional dysregulation for emotional facial expressions. Avoidance of pain cues may be a coping strategy that these individuals develop under stressful conditions. Implications, limitations, and directions for future research are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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