36 results on '"Ebrahimi, Mohammad"'
Search Results
2. The impact of acceptance and commitment therapy on college students' suicidal ideations, a tendency to self-harm, and existential anxiety.
- Author
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Jalali Azar, Rojin, Ebrahimi, Mohammad Ismail, Haddadi, Arya, and Yazdi-Ravandi, Saeid
- Subjects
ACCEPTANCE & commitment therapy ,SUICIDAL behavior ,SUICIDAL ideation ,ANXIETY ,CONVENIENCE sampling (Statistics) ,COLLEGE students ,FOSTER children ,ANALYSIS of covariance - Abstract
Individuals experiencing suicidal thoughts and self-harming behaviors often struggle with various mental health, social, family, and personal challenges. Existential anxiety or meaninglessness may contribute to these thoughts and behaviors. The current study aims to examine the impact of Acceptance and Commitment Therapy on reducing existential anxiety and the propensity for self-harming behaviors and suicidal ideations among students. The present study was quasi-experimental, and its research design was pre-test-post-test with a control group. The statistical population of the research consisted of the students of Hamedan Azad University in 2022. The convenience sampling method was used to select the sample. After the Self-Harm Inventory (1998), Lawrence Good's Preliminary Measure of Existential Anxiety (1974), and Beck's Scale-for-Suicidal-Ideation (1961) were implemented among the statistical population of the research. The essential data was collected and analyzed using SPSS-26 software. Sixteen individuals with scores above the cut-off point were chosen and randomly divided into two groups of eight people each: An intervention group and a control group. The intervention group was exposed to the Acceptance and Commitment Therapy group for eight sessions. Multivariate analysis of covariance (MANCOVA) was used to analyze the data. The results revealed that Acceptance and Commitment Therapy significantly reduced existential anxiety (P ≤ 0.001), self-harming tendencies (P ≤ 0.001), and suicidal ideations (P ≤ 0.001). The study's findings suggest that Acceptance and Commitment Therapy is essential in reducing suicidal ideations, self-harm tendencies, and existential anxiety. As a result, it effectively promotes mental health and fosters community well-being. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Taxonomy and new pictorial key of Iranian scorpions (Arachnida: Scorpionida).
- Author
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Azizi, Kourosh, Ebrahimi, Mohammad, Amin, Masoumeh, Soltani, Aboozar, Vahedi, Mozaffar, and Kalantari, Mohsen
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SCORPIONS , *ARACHNIDA , *SCORPION venom , *DIAGNOSTIC specimens , *TAXONOMY , *RESEARCH personnel - Abstract
Scorpions (Arachnida: Scorpions) are one of the medically important oldest arthropods. They have been one of the humans' interests in terms of special morphology, painful stings, mortality, and behavioral attractions for many years. Diagnosis of scorpions is based on morphological characteristics and molecular methods. But, one of the most important and fundamental problems of identifying the Iranian scorpions is the lack of a comprehensive method. Due to the fact that a relatively long time has not passed since the classification of scorpions in Iran and there are no definitive divisions about the genera and species in the country, the current pictorial key was provided to identify the Iranian scorpions. In this study, various methods were used to catch the scorpions. For preparing the pictorial key, different genera of scorpions were collected from urban, rural, plain, and mountain areas in different parts of Iran as well as some archived specimens from the medical arachnid's Museum of Shiraz University of Medical Sciences were used from 2010 to 2020 collection boxes. The key presented in this study was prepared only based on morphological features. It was necessary to remind a few points about this key and its use. Considering the above-mentioned points, this key was provided for 16 genera, 64 species, and 3 families of Iranian scorpions, and the results of other researchers are included in it. The study of various aspects of scorpion life, especially faunistic studies has been recently considered in Iran. Various methods such as molecular methods and composition of scorpion venom can be used for classification, the most common of which are morphological features that have a long history. Therefore, the need to provide a key to detect scorpions in the country has a special priority. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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4. A narrative from the right to the city in Iran: the theoretical–practical continuum of urban development in Bandar Abbas.
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Ebrahimi, Mohammad, Alavi, Ali, Meshkini, Abolfazl, and Sadri, Hossein
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URBAN growth ,PUBLIC spaces ,LABOR organizing ,CAPACITY building ,URBAN planners ,URBAN life - Abstract
Many urban planners have used Lefebvre's concept of the right to the city as a dominant approach in urban studies. In this research, we try to draw a framework for the urban development of Bandar Abbas through the application of urban development components based on the right-to-the-city approach. Interpretive structural modeling is used in drawing urban development based on the right-to-the-city approach. The centrality of citizens in decision-making, self-management of space, the right to planning and designing the space, the right to transparency, and access to information at the first class are considered the key variables of Bandar Abbas urban development. The right to manage and organize the space, the right to accountability, democratic (institutional) capacity building, and social priorities in the decision-making process are the subcomponents of Bandar Abbas urban development. The presented model is the realization of people in space, where people take over the space and enjoy the benefits of urban life, if needed, they can freely express their opinions and limitations in the space and organize the city according to their needs. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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5. Investigation of the biofilm formation in extra-intestinal pathogenic Escherichia coli ST131 strains and its correlation with the presence of fimH, afa, and kpsMSTII genes.
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Ebrahimi, Mohammad Taha, Hedayati, Manouchehr Ahmadi, Pirlar, Rima Fanaei, Mortazavi, Newsha, Nazari, Mohsen, Ahmadi, Amjad, Hemmati, Jaber, and Erfani, Yousef
- Abstract
Escherichia coli sequence type 131 (ST131) is a multidrug-resistant strain with the global dissemination. Biofilm formation-related factors include the most important virulence factors in extra-intestinal pathogenic E. coli (ExPEC) ST131 strains causing infections with treatment-limited subjects. This study aims to investigate the biofilm formation ability and its correlation with the presence of fimH, afa, and kpsMSTII genes in clinical isolates of ExPEC ST131. In this regard, the prevalence and characteristics of these strains collected and evaluated. The results revealed strong, moderate, and weak attachment abilities related to biofilm formation attributes in 45%, 20%, and 35% of strains, respectively. In the meantime, the frequency of the fimH, afa, and kpsMSTII genes among the isolates was observed as follows: fimH positive: 65%; afa positive: 55%; and kpsMSTII positive: 85%. The results convey a significant different of biofilm formation ability between clinical E. coli ST131 and non-ST131 isolates. Furthermore, while 45% of ST131 isolates produced strong biofilms, only 2% of non-ST131 isolates showed the ability to form strong biofilms. The attending of fimH, afa, and kpsMSTII genes in the majority of ST131 strains demonstrated a key role leading to biofilm formation. These findings suggested the application of fimH, afa, and kpsMSTII gene suppressors for treating biofilm infections caused by drug-resistant ST131 strains. [ABSTRACT FROM AUTHOR]
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- 2023
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6. The effect of dopaminergic neuron transplantation and melatonin co-administration on oxidative stress-induced cell death in Parkinson's disease.
- Author
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Asemi-Rad, Azam, Moafi, Maral, Aliaghaei, Abbas, Abbaszadeh, Hojjat-Allah, Abdollahifar, Mohammad-Amin, Ebrahimi, Mohammad-Javad, Heidari, Mohammad Hasan, and Sadeghi, Yousef
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PARKINSON'S disease ,CELL death ,DOPAMINERGIC neurons ,CELL size ,WESTERN immunoblotting ,SUBSTANTIA nigra ,NEUROGLIA - Abstract
A gradual degeneration of the striatum and loss of nigral dopamine cells are characteristic of Parkinson's disease. Nowadays, combination therapy for neurodegenerative disease is considered. This study aimed to investigate the effects of melatonin and dopaminergic neurons derived from adipose tissue stem cells (ADSCs) in a rat model of Parkinson's disease. Parkinson's disease was induced in rats using neurotoxin 6-Hydroxydopamine. The treatment was performed using melatonin and dopaminergic neurons transplantation. Subsequently, behavioral tests, western blot analysis for Caspase-3 expression, GSH (Glutathione) content and stereology analysis for the volume and cell number of substantia nigra and striatum were performed. Treatment with melatonin and dopaminergic neuron transplantation increased the number of neurons in substantia nigra and striatum while the number of glial cell and the volume of substantia nigra and striatum did not show significant change between groups. Western blot analysis for caspase 3 indicated the significant differences between groups. The results also indicated the increased level of glutathione (GSH) content in treatment groups. this study showed that combination therapy with melatonin and dopaminergic neurons could greatly protect the neurons, reduce oxidative stress and improve the symptoms of PD. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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7. Stability improvement of polyaniline nanocomposite immunosensor for early detection of insulin receptor antibody as biomarker of type 2 diabetes.
- Author
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Farrokhnia, Mohammadreza, Amoabediny, Ghassem, Ebrahimi, Mohammad, Ganjali, Mohammad Reza, and Arjmand, Mohammad
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POLYANILINES ,RECEPTOR antibodies ,INSULIN antibodies ,TYPE 2 diabetes ,INSULIN receptors ,NANOCOMPOSITE materials ,BIOMARKERS - Abstract
Polyaniline nanocomposite with controllable properties was used to design and fabricate a novel electrochemical immunosensor for the early detection of type 2 diabetes. Insulin receptor antibody is a powerful predictor of type 2 diabetes development in individuals. A systematic study was carried out to investigate the effects of different polyaniline layers and the Nafion layer on the morphological, chemical, and electrochemical properties of nanocomposite immunosensor, especially the stability. The bioengineered Nafion-Au nanoparticles-polyaniline/gold electrode demonstrated outstanding electrocatalytic performance in the detection of insulin receptor antibodies with a high sensitivity (136.21 µA.ng
−1 .ml.cm−2 ) in a linear range from 0.001 to 200 ng.ml−1 as well as a low detection limit of 1.827 pg.ml−1 , response time within 10 min, remarkable selectivity, and significant stability of 80 days. Therefore, the developed immunosensor is a suitable nanocomposite platform for insulin receptor antibody level determination in human plasma. [ABSTRACT FROM AUTHOR]- Published
- 2022
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8. A new region-specific empirical model for prediction of ground motion significant duration in Turkey.
- Author
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Yaghmaei-Sabegh, Saman, Karimzadeh, Shaghayegh, Ebrahimi, Mohammad, Ozsarac, Volkan, and Du, Wenqi
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GROUND motion ,PREDICTION models ,EARTHQUAKE damage ,SEISMIC waves ,MOTION ,EARTHQUAKES - Abstract
Ground motion amplitude, frequency content, and duration are commonly identified as the main features of seismic waves affecting structural demand. Among these parameters, earthquake duration can have a substantial influence on assessment of structural seismic demand. The paper proposes a new empirical model for predicting the significant duration of ground-motion records in Turkey. Significant duration is an important parameter in determining the damage potential of earthquakes and is defined as the time interval between two specific values of Arias intensity. The proposed model is as function of moment magnitude ( M w ), Joyner-Boore distance ( R jb ), time-averaged shear-wave velocity in the top 30 m ( V S 30 ), and fault mechanism ( F m ). In the regression process, a database consisting of 850 records from 408 earthquakes in Turkey is used. According to the physics of the problem, mixed effect regression is employed. Next, besides residual analysis, comparison of the mean values with the other prediction models are performed. The results of this study indicate that the new model is satisfactory while reliable estimates of significant duration could be assessed for the Turkish region. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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9. Intensifying antibacterial and electrochemical behaviors of CuO induced-ion exchange membrane for water treatment.
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Mohsen Hosseini, Sayed, Golshanikia, Parisa, Habibi, Morteza, Jashni, Elham, Shen, Jiangnan, and Ebrahimi, Mohammad
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ION-permeable membranes ,WATER purification ,COPPER oxide ,COMPOSITE membranes (Chemistry) ,UNIFORM spaces - Abstract
The PVC-based heterogeneous type cationic membranes were constructed by incorporation of copper oxide nanoparticles to enhance the antimicrobial and electrochemical behaviors of them in water treatment. The SOM and SEM/EDX indicated uniform structure for the fabricated membranes. Contact-angle results showed improvement of membrane surface hydrophilicity in presence of CuO NPs. Water uptake also changed by incorporation of CuO. According to 3D surface results, composite membranes showed rougher surface in comparison with pristine ones. The potential, t-number and permselectivity enhanced initially up to 1%wt CuO concentration and then declined by further CuO from 1 to 4%wt. All mentioned parameters increased again at 8%wt nanoparticles concentration. Ionic flux promoted for blended membranes up to 2%wt CuO and then declined by growing CuO. Blended membrane containing 0.5%wt CuO with lowest electrical resistance (< 9.6 Ω.cm
2 ) and (> 94%) selectivity showed more appreciate act compared to reported ones. The CuO induced-ion exchange membranes exhibited superior antibacterial effect. [ABSTRACT FROM AUTHOR]- Published
- 2022
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10. A fault-tolerant steer-by-wire system based on angular position estimation.
- Author
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Mortazavizadeh, Seyed Abolfazl, Ghaderi, Ahmad, Hajian, Masood, and Ebrahimi, Mohammad
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POSITION sensors ,RELIABILITY in engineering ,REDUNDANCY in engineering ,SENSOR placement ,AUTOMOBILE steering gear ,FAULT-tolerant computing - Abstract
While steer-by-wire (SBW) systems benefit from improved performance and comfort, they require a large number of sensors impacting whole system reliability. In order to address this challenge fault tolerance property against sensor faults has to be improved. Application of redundancy for the sensors is the best solution proposed so far. This paper proposes a novel solution of analytical redundancy based on various position estimation methods for both electrical motor and steering wheel position sensors. Three different estimation techniques including extended programmable cascaded low-pass filter (EPCLPF), stator flux linkage estimator using stator currents, as well as stator flux linkage estimator using stator voltages are proposed for this purpose. The faulty sensors are recognized using a voting technique in which a comparison between the sensors' outputs with the estimated values is made. In this way, the SBW system reliability is highly improved with no additional cost and space. Simulation and experimental results are presented to confirm the presented fault tolerant SBW system capabilities. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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11. Temporal correction of irregular observed intervals of groundwater level series using interpolation techniques.
- Author
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Zaghiyan, Mohammad Reza, Eslamian, Saeid, Gohari, Alireza, and Ebrahimi, Mohammad Saleh
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INTERPOLATION ,WATER table ,GROUNDWATER recharge ,GROUNDWATER flow ,WATER levels ,HERMITE polynomials ,GROUNDWATER - Abstract
Groundwater level observations due to the lack of synoptic water-level measurements are often available with irregular time intervals. The results lead to an inaccurate understanding of the parameters affecting groundwater level changes and their time delays. This paper presents a simple and low-cost approach to interpolate the irregular, periodic intervals of recorded groundwater level data for the Najafabad aquifer located in central Iran. Forty-six monitoring wells with an average of 20 years of data were used for this study. Piecewise cubic Hermite interpolating polynomial (PCHIP), cubic spline, linear, and nearest neighbor are the selected interpolation methods. Cross-validation with leave-one-out technique was also applied to evaluate the accuracy of the methods under three conditions, including low, average, and high groundwater level decline. The analysis proved that (1) PCHIP interpolation showed a high performance in all of the groundwater level decline conditions (0.22 < RMSE < 0.59 and 0.72 < R
2 < 0.98). (2) Under slight and without abrupt fluctuations of groundwater level conditions, cubic spline showed a better performance than the linear interpolation (R2 = 0.98, RMSE = 0.49 for cubic spline and R2 = 0.98, RMSE = 0.51 for linear). The selected approach reduces the uncertainty in the study of issues such as changes in groundwater recharge and storage, groundwater flow directions, surface–groundwater interaction, and groundwater modeling. [ABSTRACT FROM AUTHOR]- Published
- 2021
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12. Fault-tolerant control of steer-by-wire systems under voltage and current sensors faults.
- Author
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Mortazavizadeh, Seyed Abolfazl, Ebrahimi, Mohammad, Ghaderi, Ahmad, and Hajian, Masood
- Abstract
Steer-by-wire (SBW) systems benefit from several advantages including lower weight, volume, and cost compared to counterpart electric power steering systems. However, system reliability is impacted since SBW performance is highly dependent on correct operation of several voltage, current, speed, yaw rate, and position sensors. This paper presents a new method in SBW system reliability improvement by introducing a novel fault detection, isolation, and reconstruction (FDIR) control technique. The proposed FDIR method detects if any fault is observed on voltage or current sensors and identifies the faulty sensor location. Additionally the identified faulty sensor's output is replaced with an estimated value to allow system continuous fault-ride through operation. The SBW system equipped with proposed FDIR technique provides fault-tolerance property against up to 3 faulty voltage or current sensors. Therefore, enhanced overall reliability is obtained at no further hardware costs associated with additional sensors redundancy solutions. The proposed technique is studied using system modelling and hardware prototyping, and its effectiveness is demonstrated using simulation and experimental results. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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13. The Immunogenicity of a Novel Chimeric Hemagglutinin-Neuraminidase-Fusion Antigen from Newcastle Disease Virus by Oral Delivery of Transgenic Canola Seeds to Chickens.
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Motamedi, Mohammad Javad, Ebrahimi, Mohammad Majid, Shahsavandi, Shahla, Amani, Jafar, Kazemi, Rouhollah, Jafari, Mahyat, and Salmanian, Ali-Hatef
- Abstract
Newcastle disease (ND) is considered as one of the most devastating infectious diseases targeting domestic birds and has considerable threat to the commercial poultry production. Two surface glycoproteins, hemagglutinin-neuraminidase (HN) and fusion (F), act as antigens in the virus structure and also play important roles in infecting host cells. In the current study, the expression of the chimeric HN-F protein in canola seeds and its immunogenicity in chickens were investigated. The HN-F gene was cloned downstream of the fatty acid elongase 1 (FAE1) promoter in the binary expression vector, pBI1400-HN-F, and introduced into rapeseed (Brassica napus L.) using Agrobacterium-mediated transformation. The amount of the HN-F glycoprotein was estimated up to 0.18% and 0.11% of the total soluble protein (TSP) in transgenic seeds and leaves of canola, respectively. Confirmatory analyses of 36 transgenic lines revealed that the HN-F gene was integrated into the genome. Subsequently, HN-F protein could be expressed and accumulated in the seed tissue. Specific pathogen-free (SPF) chickens immunized orally with recombinant HN-F showed a significant rise in specific and hemagglutination inhibition (HI) antibodies 35 to 42 days post the first administration. The results implied the potential of transgenic canola seed-based expression for oral delivery of NDV immunogenic glycoproteins. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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14. Trend and status of out-of-pocket payments for healthcare in Iran: equity and catastrophic effect.
- Author
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Rezaei, Satar, Woldemichael, Abraha, Ebrahimi, Mohammad, and Ahmadi, Sina
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- 2020
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15. The effects of industrial noise exposure on lipid peroxidation and antioxidant enzymes among workers.
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Bagheri Hosseinabadi, Majid, Khanjani, Narges, Ebrahimi, Mohammad Hossein, Mirbadie, Seyed Reza, and Biganeh, Jamal
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OXIDANT status ,NOISE control ,SOUND pressure ,LIPIDS ,NOISE ,INSULIN aspart - Abstract
Purpose: The aim of this study was to measure individual exposure to noise and its effect on the levels of lipid peroxidation and enzymatic antioxidant defense. Methods: In this cross-sectional study, 94 male workers working in a food factory in Shahroud, Iran, were selected as the case group and 112 people were also included as the control group. The level of exposure to noise was measured using a dosimeter and the equivalent level was calculated. The levels of malondialdehyde (MDA), catalase (Cat), superoxide dismutase (SOD), and Total Antioxidant Capacity (TAC) were measured in the serum samples of all participants. Independent t test, one-way ANOVA, and multivariate linear regression were used to analyze the data. Results: The levels of MDA, Cat, and TAC were significantly higher in staff exposed to noise than in the controls. The starch and warehouse units' staff were exposed to the highest (99.3 ± 3.23 dB) and lowest (77.1 ± 9.68 dB) mean levels of sound pressure. Based on the linear regression model, noise exposure level was the most important predictor variable for levels of MDA (β = 0.48, CI 95% = 0.04–0.93), Cat (β = 0.43, CI 95% = 0.05–0.83), and TAC (β = 0.11, CI 95% = 0.06–0.16). Conclusions: Noise exposure increases the production of free radicals. As exposure rate increases, the levels of MDA, Cat, and TAC enzymes increase as well. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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16. The ideal entropy of BCI-algebras and its application in the binary linear codes.
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Ebrahimi, Mohammad and Izadara, Alireza
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BINARY codes , *CODING theory , *LINEAR codes , *AUTOMORPHISMS , *ISOMORPHISM (Mathematics) - Abstract
This paper defines the concept of ideal entropy for BCI-algebras in general, and it tries to describe some of its properties. Moreover, the present study will show that F2n (i.e., sets of every binary code word of length n) is a BCI-algebra, and that each ideal of F2n is a linear code. The present study defines the concept of cosets by using the quotient BCI-algebra F2nI and obtains their properties. This study defines the complement of a linear code, which is itself a linear code, which is denoted by the symbol Cc. Further, the present study defines the standard complement of a linear code, which is unique. This study proves that each equivalence class in F2n/Cc contains one and only one code word of the linear code C. This property can be used for decoding. Finally, the present study shows that two linear codes are equivalent if and only if they have the same ideal entropy. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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17. Human Umbilical Cord Matrix Stem Cells Reverse Oxidative Stress-Induced Cell Death and Ameliorate Motor Function and Striatal Atrophy in Rat Model of Huntington Disease.
- Author
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Ebrahimi, Mohammad Javad, Aliaghaei, Abbas, Boroujeni, Mahdi Eskandarian, Khodagholi, Fariba, Meftahi, Gholamhoussein, Abdollahifar, Mohammad Amin, Ahmadi, Houssein, Danyali, Samira, Daftari, Mahtab, and Sadeghi, Yousef
- Subjects
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HUNTINGTON disease , *UMBILICAL cord , *STEM cells , *OXIDATIVE stress , *CELL death , *MOTOR ability , *LABORATORY rats - Abstract
Huntington disease (HD) is an inherited disorder hallmarked by progressive deterioration of specific neurons, followed by movement and cognitive anomalies. Cell therapy approaches in neurodegenerative conditions have concentrated on the replenishment of lost/dying neurons with functional ones. Multipotent mesenchymal stem cells (MSCs) have been represented as a potential remedy for HD. In this study, we evaluated the in vitro and in vivo efficacy of umbilical cord matrix stem cells (UCMSCs) and their paracrine effect against oxidative stress with a specific focus on HD. To this end, UCMSCs were isolated, immunophenotypically characterized by the positive expression of MSC markers, and exhibited multilineage potentiality. Besides, synthesis of neurotrophic factors of GDNF and VEGF by UCMSC was confirmed. Initially, PC12 cells were exposed to superoxide in the presence of conditioned media (CM) collected from UCMSC (UCMSC-CM) and cell viability plus neuritogenesis were measured. Next, bilateral striatal transplantation of UCMSC in 3-nitropropionic acid (3-NP) lesioned rat models was conducted, and 1 month later, post-graft analysis was performed. According to our in vitro results, CM of UCMSC protected PC12 cells against oxidative stress and considerably enhanced cell viability and neurite outgrowth. On the other hand, transplanted UCMSC survived, decreased gliosis, and ameliorated motor coordination and muscle activity, along with an increase in striatal volume as well as in dendritic length of the striatum in HD rats. Collectively, our findings imply that UCMSCs provide an enriched platform by largely their paracrine factors, which downgrades the unfavorable effects of oxidative stress. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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18. A comparison of ocular complaints and their relationship with sleepiness between professional and non-professional computer users.
- Author
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Ebrahimi, Mohammad Hossein, Shayestefar, Mina, Firoozi, Ghazale, and Ghadamgahi, Samane
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COMPUTER users , *DROWSINESS , *DRY eye syndromes , *ASTHENOPIA , *EYESTRAIN , *DESCRIPTIVE statistics , *CROSS-sectional method , *QUESTIONNAIRES - Abstract
This study was conducted to investigate ocular complications and their relationship with sleep problems between IT students at Shahroud University of Technology as professional computer users and public health students at Shahroud University of Medical Sciences as non-professional computer users. This descriptive, cross-sectional study was conducted in 2014-2015 on 290 students, including 145 IT and 145 public health students. The students were selected by simple random sampling. Data were collected using five questionnaires, including a demographic questionnaire, the Ocular Surface Disease Index (OSDI), the Visual Fatigue Questionnaire, the Epworth Sleepiness Scale (ESS) and the STOP-BANG, and an examination for visual acuity. Data were analyzed in SPSS-22 using descriptive and inferential statistics and the level of statistical significance was set at P < 0.05. The comparisons showed a significant difference in the mean scores of the OSDI, VFQ and ESS between the male and female students, as all these scores were higher in the female students; however, no significant differences were observed in these scores between the professional and non-professional users. Given the significant direct relationships between the scores of the four questionnaires, it can be argued that sleep disorders and ocular disorders have reciprocal effects on each other. Sleepiness, dry eye and eye strain were not different between the groups of professional and non-professional computer users, but long hours of computer and cellphone use were observed so all students need to receive further education and correct ergonomics regardless of their field of study. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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19. Recombinant VP2 expressed in baculovirus and adjuvanted with TIR-TLR7: a vaccine candidate against infectious bursal disease virus.
- Author
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Ebrahimi, Mohammad Majid, Shahsavandi, Shahla, Shayan, Parviz, Goudarzi, Hossein, and Masoudi, Shahin
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BACULOVIRUSES , *IMMUNOLOGICAL adjuvants , *ANTIGENS , *TOLL-like receptors , *IMMUNE response - Abstract
Currently, a variety of immunostimulatory molecules are used as adjuvants in combination with poor immunogenic recombinant infectious bursal disease virus (IBDV) vaccine antigen. TIR domain of Toll-like receptors (TLRs) triggers the interleukin-1 (IL-1) signaling cascade which plays a critical role in immune responses against infectious agents. For this study, the bacmid DNA pBac-VP2 of a field isolate was generated and transfected to Sf9 insect cells to produce recombinant VP2 (rVP2). In addition, based on in silico analysis, the cDNA encoding the conserved TIR domain of TLR7 (TIR-TLR7) contain the IL-1 receptor was synthesized and used as an adjuvant. We further evaluated the ability of rVP2/TIR-TLR7 vaccine candidate to induce specific immune responses in specific pathogen-free (SPF) chickens and compared the efficacy by challenging with the virulent IBDV. The results indicate that rVP2/TIR-TLR7-adjuvanted vaccine elicited humoral immune responses and protected chickens against IBDV infection. Higher levels of neutralizing IBDV antibody titers were observed in chickens intramuscularly immunized with rVP2/TIR-TLR7 than those injected with rVP2 alone. The antibody titers were higher in chickens which received booster injection. Furthermore, chickens immunized with rVP2/TIR-TLR7 in the prime and boost groups had significant protection against a virus challenge. The survival rate was 70 and 90% after the primary and booster rVP2/TIR-TLR7 vaccinations, respectively, and indicated that they were protected from virus challenge. Despite the unvaccinated control group, the immunized chickens with rVP2/TIR-TLR7 did not show any clinical signs and histopathological changes of the bursa. Our results demonstrate that TIR-TLR7 is a potential vaccine adjuvant and can induce antigen-specific immune responses induced by rVP2 for protection against IBDV infection. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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20. Eccentricity fault detection in permanent magnet synchronous generators using stator voltage signature analysis.
- Author
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Safa, Hossein, Ebrahimi, Mohammad, Zarchi, Hossein, and Abshari, Mohammad
- Abstract
In this paper, an index is proposed for the detection of static eccentricity (SE), dynamic eccentricity (DE), and mixed eccentricity (ME) in a three-phase permanent magnet synchronous generator (PMSG). The proposed index is the amplitude of the sideband components with a particular frequency pattern which is extracted from the spectrum of the stator voltage. This index can be used in no load state prior to the loading of the generator which can cause damage in eccentricity conditions. Moreover, the proposed index works properly in loaded condition. Extraction of the proper indexes highly depends on precise computation of the necessary signals. Therefore, in order to fulfil the required precision, the time-stepping finite element method (TSFEM) is used to model the PMSG under eccentricity fault and to calculate the stator voltage as an appropriate signal for processing. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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21. Two dissimilar approaches to dynamical systems on hyper MV -algebras and their information entropy.
- Author
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Mehrpooya, Adel, Ebrahimi, Mohammad, and Davvaz, Bijan
- Abstract
Measuring the flow of information that is related to the evolution of a system which is modeled by applying a mathematical structure is of capital significance for science and usually for mathematics itself. Regarding this fact, a major issue in concern with hyperstructures is their dynamics and the complexity of the varied possible dynamics that exist over them. Notably, the dynamics and uncertainty of hyper MV -algebras which are hyperstructures and extensions of a central tool in infinite-valued Lukasiewicz propositional calculus that models many valued logics are of primary concern. Tackling this problem, in this paper we focus on the subject of dynamical systems on hyper MV -algebras and their entropy. In this respect, we adopt two varied approaches. One is the set-based approach in which hyper MV -algebra dynamical systems are developed by employing set functions and set partitions. By the other method that is based on points and point partitions, we establish the concept of hyper injective dynamical systems on hyper MV -algebras. Next, we study the notion of entropy for both kinds of systems. Furthermore, we consider essential ergodic characteristics of those systems and their entropy. In particular, we introduce the concept of isomorphic hyper injective and hyper MV -algebra dynamical systems, and we demonstrate that isomorphic systems have the same entropy. We present a couple of theorems in order to help calculate entropy. In particular, we prove a contemporary version of addition and Kolmogorov-Sinai Theorems. Furthermore, we provide a comparison between the indispensable properties of hyper injective and semi-independent dynamical systems. Specifically, we present and prove theorems that draw comparisons between the entropies of such systems. Lastly, we discuss some possible relationships between the theories of hyper MV -algebra and MV -algebra dynamical systems. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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22. Reflected shock tube experiments on aeroacoustic signature of hot jets.
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Jahromi, Iman, Ebrahimi, Mohammad, and Ghorbanian, Kaveh
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SHOCK tubes , *REPLICATION (Experimental design) , *BALLISTIC ranges , *MECHANICAL shock , *AZIMUTHAL equidistant projection (Cartography) - Abstract
We used a reflected shock tube to investigate the acoustic signature of a hot jet at the far-field. Experiments were performed at Mach = 1.4 and a total temperature of T = 950 Kelvin. Far-field acoustic signatures of the hot jet at six polar angles θ = 15˚ to θ = 90˚ from the jet axis) were measured and imaged by the means of continuous wavelet transform in scalograms. The results were compared with experiments from a steady test facility at similar test conditions. Further, the primary characteristics of noise events in jet far-field were compared with analytical models considering wavepacket as the main source of jet noise. The results indicate that higher frequency events at θ = 90˚ occur with a small time shift relative to the low azimuthal mode base event. This phenomenon might be the main reason why the acoustic signal at the side angles behaves more noisily than at low polar angles. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
23. Evaluation of the influences of various force magnitudes and configurations on scoliotic curve correction using finite element analysis.
- Author
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Karimi, Mohammad, Ebrahimi, Mohammad, Mohammadi, Ali, and McGarry, Anthony
- Abstract
Scoliosis is a lateral curvature in the normally straight vertical line of the spine, and the curvature can be moderate to severe. Different treatment can be used based on severity and age of subjects, but most common treatment for this disease is using orthosis. To design orthosis types of force arrangement can be varied, from transverse loads to vertical loads or combination of them. But it is not well introduced how orthoses control scoliotic curve and how to achieve the maximum correction based on force configurations and magnitude. Therefore, it was aimed to determine the effect of various loads configurations and magnitudes on curve correction of a degenerative scoliotic subject. A scoliotic subject participated in this study. The CT-Scan of the subject was used to produce 3D model of spine. The 3D model of spine was produced by Mimics software and the finite element analysis and deformation of scoliotic curve of the spine under seven different forces and in three different conditions was determined by ABAQUS software. The Cobb angle in scoliosis curve decreased significantly by applying forces. In each condition depends on different forces, different corrections have been achieved. It can be concluded that the configurations of the force application mentioned in this study is effective to decrease the scoliosis curve. Although it is a case study, it can be used for a vast number of subjects to predict the correction of scoliosis curve before orthotic treatment. Moreover, it is recommended that this method and the outputs can be compared with clinical findings. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
24. Examining responses of chicken embryonic neural stem cell to infectious laryngotracheitis virus infections.
- Author
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Shahsavandi, Shahla, Jamshidi-Navroud, Zahra, Firouzi, Masoumeh, and Ebrahimi, Mohammad
- Subjects
CHICKEN diseases ,POULTRY industry ,NEURAL stem cells ,MICROBIAL virulence ,EMBRYONIC stem cells - Abstract
Infectious laryngotracheitis virus (ILTV) infection causes economic losses in the poultry industry. Outbreaks of the infection in commercial poultry are controlled by using attenuated live vaccines. The genomic and antigenic characteristics between virulent and vaccine strains of ILTV are very similar, thus the differential diagnosis of ILTV strains is targeted in controlling programs. Here, the chicken embryonic neural stem (cENS) cell serves as a host model to study virulence characteristics of ILTVs. The susceptibility of cENS cells to different ILTV strains infection was investigated by analyzing the impact of infection on cell death, virus latency, and determining the host cell responses. We found that cENS cells are highly susceptible to vaccine strain ILTV infection. Upon infection, the strain showed faster replication kinetics in cell culture and marked cytopathic effects with affecting the expression of cellular neuropeptide Y (NPY). Virulent strain was able to enter cENS cells, but no infectious virus was produced at third passage. The establishment of latency state was confirmed by molecular detection of viral ICP4 gene and virus reactivation assay. In contrast to vaccine strain, transcription level of cellular NPY was also upregulated significantly following virulent strain infection. The difference expression pattern of NPY in ILTV strains-infected cells is most closely with the presence of CPE in culture. The neural stem cell system may provide the most relevant tool for differential diagnosis of ILTV strains. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
25. The investigation of laser shock peening effects on corrosion and hardness properties of ANSI 316L stainless steel.
- Author
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Ebrahimi, Mohammad, Amini, Saeid, and Mahdavi, Seyed
- Subjects
- *
LASER peening , *MECHANICAL behavior of materials , *STAINLESS steel corrosion , *HARDNESS , *SHOCK waves - Abstract
Laser shock peening (LSP) is known as a post processing surface treatment which can improve the mechanical properties of some materials. Shock waves are generated by confining the laser-induced plasma to cause a large pressure shock wave over a significant surface area. In the present study, effects of LSP on the electrochemical corrosion and micro hardness properties of 316L stainless steel alloy were investigated by changing the laser parameters such as the laser spot size, the average number of impacts, and the laser intensity. Since laser parameters do not cover the desired region of LSP, we have to use the proper design of experiment method, in which the D-optimal design of MATLAB was selected. Results revealed that by increase in irradiance, number of impacts and spot size of laser beam, improvement in the surface micro hardness, and corrosion resistance is achieved. Also, due to unexpected drop into the outcome of our experiments, it was found that the contamination of the transparent overlay and reduction of the absorption coefficient of the absorbent layer play a key role to reduce the efficiency of the mechanical impacts. So, by changing the experimental conditions, even better results are expected. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
26. Evaluation of slip rate on Astara fault system, North Iran.
- Author
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Barzegari, Amir, Esmaeili, Rasoul, Ebrahimi, Mohammad, Faghih, Ali, Ghorashi, Manucher, and Nazari, Hamid
- Subjects
GEOLOGIC faults ,GEOLOGICAL research ,EARTHQUAKES ,EARTHQUAKE hazard analysis ,GEODETIC techniques - Abstract
Due to its strategic location, the Astara fault system (AFS), which is located in Iran, has given rise to a number of earthquakes. In spite of its frequent seismic events, limited information is available for AFS. Slip rate is one of the important variables for future scrutiny of seismic risk of this fault system. The main objective of this research is to study slip rates at intermediate and short terms for this fault system using geological, geodetic observations and empirical method. Using the geological data, the intermediate-term horizontal and vertical slip rates for AFS have been determined to be 2.8±0.2 and 0.27±0.03 mm/year, respectively. In addition, the short-term slip rates of the fault, based on the geodetic method (using displacement values of two GPS stations: HASH and DAMO) and assuming attenuation of 60% (to fold the sediment of South Caspian Basin and shortening of Talesh Mountain range), determined to be 1.23±0.03 and 2.05±0.05 mm/year for the horizontal and vertical slips, respectively. Finally, evaluation of the slip rate using empirical relationship yields 10 mm/year for the entire fault system, which seems rather implausible. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
27. Evaluating Hydrogeochemical Processes Regulating Groundwater Quality in an Unconfined Aquifer.
- Author
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Nematollahi, Mohammad, Ebrahimi, Pooria, and Ebrahimi, Mohammad
- Published
- 2016
- Full Text
- View/download PDF
28. Valproic acid may exerts its cytotoxic effect through rassf1a expression induction in acute myeloid leukemia.
- Author
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Davood, Zare-Abdollahi, Shamsi, Safari, Ghaedi, Hamid, Sahand, Riazi-Isfahani, Mojtaba, Ghadyani, Mahdi, Tabarraee, Reza, Mirfakhraie, Ebrahimi, Mohammad, Miri-Moosavi, Reyhaneh, Boosaliki, Sara, and Davood, Omrani
- Abstract
In acute myeloid leukemia (AML), despite the acceptance of standard intensive chemotherapy as an optimal induction regimen for all age groups, in the elderly patients, the best treatment should meet the challenge of multiple factors like age, comorbidities, and cytogenetics, making them ineligible for standard induction chemotherapy. Using the current low-intensity therapies like decitabine, azacitidine, and low-dose cytarabine as a single arm, outcomes for these patients remain poor. As a histone deacetylase inhibitor valproic acid (VPA) exhibit anticancer activity by triggering apoptosis, the mechanism of which is not yet completely clarified. To explore the possible connection between VPA treatment and the Hippo pathway as an apoptosis stimulating route, we also explore the expression of major components of this pathway and for the first time we postulate a relationship between VPA treatment and cell death induction through RASSF1A expression induction. Furthermore, we demonstrate that autophagy inhibition by chloroquine (CQ) significantly augmented the cytotoxic effect of VPA on AML cells, especially in those with unfavorable and normal karyotype. Regarding that VPA and CQ are well-tolerated drugs and our presumptive results of usefulness of VPA + CQ in three cytogenetic risk groups of AML, this combinatorial therapy could represent an attractive treatment option for older AML patients unfit for intensive therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
29. The entropy of semi-independent hyper MV-algebra dynamical systems.
- Author
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Mehrpooya, Adel, Ebrahimi, Mohammad, and Davvaz, Bijan
- Subjects
- *
FUZZY mathematics , *ENTROPY , *DYNAMICAL systems , *ATTRACTORS (Mathematics) , *MATHEMATICS theorems - Abstract
In this paper, the notion of a semi-independent dynamical system on a hyper MV-algebra is introduced. The concept of the entropy for a semi-independent hyper MV-algebra dynamical system is developed, and its characteristics are considered. The notion of equivalent semi-independent systems is defined, and it is proved the fact that two equivalent semi-independent hyper MV-algebra dynamical systems have the same entropy. Theorems to help calculate the entropy are given. Specifically, a new version of Kolmogorov-Sinai Theorem has been proved. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
30. Analysis of Genetic Diversity and Population Structure of Confectionery Sunflower (Helianthus annuus L.) Native to Iran.
- Author
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Jannatdoust, Marjan, Darvishzadeh, Reza, Ziaeifard, Roghayyeh, Ebrahimi, Mohammad Ali, Malek, Hamid Hatami, Gholinezhad, Esmaeel, and Hatamnia, Ali Asghar
- Abstract
Genetic diversity within and among 50 populations of confectionery sunflower (Helianthus annuus L.) collected from different geographical areas of Iran was evaluated by using microsatellite and retrotransposon markers. The number of alleles (Na) in SSR loci ranged from 2 to 3 with an average of 2.1. The polymorphic bands in retrotransposon markers ranged from 7 in locus CR-UR1 to 15 in locus CR-816 with a mean value of 11.33. Herarchical clustering of individuals (50 × 5 = 250) by neighbor joining method in DARwin5 software subdivided them into three groups. Using Bayesian method in the software pakage of Structure, the studied individuals were subdivided into two sub-populations. Principal coordinate analysis revelaed that the two first components explaine 7.86 and 6.16% of the total variance, respectively. Analysis of molecular variance revealed a higher level of genetic variation within (70%) than between (30%) populations. High molecular variation among individuals within population possibly is due to high allogamy nature of the sunflower plant. Low genetic variation observed between populations could be considered as a consequence of genetic equilibrium that has occurred over the long period of cultivation of confectionery sunflower in this area as well as seed exchange among regions. The traditional assumption that selecting genotypes of different geographical origin will maximize the diversity available to a breeding project does not hold in confectionery sunflower. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
31. An ant-based approach to cluster peers in P2P database systems.
- Author
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Ebrahimi, Mohammad and Rouhani Rankoohi, Seyed
- Subjects
PEER-to-peer architecture (Computer networks) ,SEARCH algorithms ,COMPUTER network architectures ,COMPUTER networks ,SCALABILITY - Abstract
Peer-to-Peer (P2P) systems with distinct advantages such as scalability, robustness and low cost have developed quickly in recent years. The resource search problem, that is to find out a peer having a desired resource, is a fundamental problem to be initially solved in most P2P applications. P2P systems can also be categorized under database systems. One of the most important problems of P2P database systems is the query processing algorithms. Even a rather small improvement over these algorithms can have a significant impact on the performance of a P2P database system. One of the most effective methods to reduce query processing cost is peer clustering. Hence, clustering peers with similar contents makes the queries directed to the appropriate cluster and thus to be efficiently answered. In this paper, we present a new peer clustering algorithm for P2P database systems that uses ant-based clustering algorithms. We have adjusted ant-based clustering algorithm to peer clustering problem. Performance evaluation of the algorithm shows its strength in clustering peers in P2P database systems to be of a higher quality and accuracy compared to the existing systems, to have a relatively short running time and to quickly converge to an optimum. Moreover, our algorithm achieves a high scalability to the increasing problem size. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
32. Apoptotic response of chicken embryonic fibroblast cells to infectious bursal disease virus infections reflects viral pathogenicity.
- Author
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Shahsavandi, Shahla, Ebrahimi, Mohammad, Sadeghi, Kaveh, and Mahravani, Homayoon
- Abstract
Infectious bursal disease virus (IBDV) induces immunodeficiency in young chickens and apoptosis in chicken embryos. To understand the relation between the viral pathogenesis and the induction of cell death, chicken embryonic fibroblast (CEF) cells were infected with IBDV intermediate (im) and very virulent (vv) strains at different MOIs. The cell viability and DNA fragmentation were evaluated in infected cells. The cellular apoptotic pathway involve was investigated by determining the activities of caspase cascade. The imIBDV strain was replicated well in CEF cells and shown higher viral titers than vvIBDV. Apoptosis changes were observed only in vvIBDV-infected CEF cells at higher MOI 48 h post infection. Efflux of cytochrome c suggests that the intrinsic pathway of the apoptotic process induced by vvIBDV infection independently of virus replication. Prediction of caspase substrates cleavage sites revealed that different IBDV strains have conserved cleavage motif pattern for VP2 and VP5 viral proteins. These findings suggest the pathogenicity of IBDV strains might be involved in the induction of apoptosis in host cells. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
33. Crystal structure of the two-subunit tRNA m1A58 methyltransferase TRM6-TRM61 from Saccharomyces cerevisiae.
- Author
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Wang, Mingxing, Zhu, Yuwei, Wang, Chongyuan, Fan, Xiaojiao, Jiang, Xuguang, Ebrahimi, Mohammad, Qiao, Zhi, Niu, Liwen, Teng, Maikun, and Li, Xu
- Published
- 2016
- Full Text
- View/download PDF
34. Dental stem cells improve memory and reduce cell death in rat seizure model.
- Author
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Shoja, Aliakbar, Sani, Mojtaba, Mirzohreh, Seyedeh-Tarlan, Ebrahimi, Mohammad Javad, Moafi, Maral, Balaghirad, Nika, Jafary, Hosein, Sagharichi, Mastoore, Aalipour, Mohammad Amin, Yassaghi, Younes, Nazerian, Yasaman, Moghaddam, Meysam Hassani, Bayat, Amir-Hossein, Ashraf, Hengameh, Aliaghaei, Abbas, and Olyayi, Paria Davoudi Bavil
- Abstract
Epilepsy is a common neurological disorder that significantly affects the quality of life of patients. In this study, we aim to evaluate the effectiveness of dental pulp stem cell (DPSC) transplantation in decreasing inflammation and cell death in brain cells, thus reducing seizure damage. We induced seizures in rats using intraperitoneal injections of pentylenetetrazole (PTZ). In the PTZ + DPSC group, we conducted bilateral hippocampal transplantation of DPSCs in PTZ-lesioned rat models. After 1 month, we performed post-graft analysis and measured some behavioral factors, such as working memory and long-term memory, using a T-maze test and passive avoidance test, respectively. We investigated the immunohistopathology and distribution of astrocyte cells through light microscopy and Sholl analysis. Additionally, we employed the Voronoi tessellation method to estimate the spatial distribution of the cells in the hippocampus. Compared to the control group, we observed a reduction in astrogliosis, astrocyte process length, the number of branches, and intersections distal to the soma in the hippocampus of the PTZ + DPSC group. Further analysis indicated that the grafted DPSCs decreased the expression of caspase-3 in the hippocampus of rats with induced seizures. Moreover, the DPSCs transplant protected hippocampal pyramidal neurons against PTZ toxicity and improved the spatial distribution of the hippocampal neurons. Our findings suggest that DPSCs transplant can be an effective modifier of astrocyte reactivation and inflammatory responses. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Application of switchable solvent-based liquid phase microextraction for preconcentration and trace detection of cadmium ions in baby food samples.
- Author
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Vessally, Esmail, Ghorbani-Kalhor, Ebrahim, Hosseinzadeh-Khanmiri, Rahim, Babazadeh, Mirzaagha, Hosseinian, Akram, Omidi, Fariborz, and Ebrahimi, Mohammad
- Subjects
- *
FOOD chemistry , *EXTRACTION (Chemistry) , *SOLVENTS , *CHEMICAL preconcentration , *CADMIUM , *BABY foods , *METAL ions - Abstract
In this paper, switchable solvent-based liquid phase microextraction was developed for preconcentration of cadmium ions and its detection by flame atomic absorption spectrometry. 2,9-dimethyl-1,10-phenanthroline (neocuproine) was used as a complexing agent in the developed sample preparation method. Conversion features of triethylamine and protonated triethylamine bicarbonate were used as a switchable solvent pair. Protonated triethylamine bicarbonate as polar form of switchable polarity solvent was successfully synthesized from triethylamine via proton transfer reaction and used for microextraction of hydrophobic cadmium complex with 2,9-dimethyl-1,10-phenanthroline at pH 7.0. The factors influencing the extraction procedure were investigated and optimized. Under the optimized conditions, limit of detection, limit of quantification, and enrichment factor for the proposed method were 0.02, 0.1 µg L, and 54.2, respectively. The calibration curve was linear in the range of 0.1-60 µg L with a correlation of determination ( r ) of 0.99. The relative standard deviation for determination of 40 µg L of Cd (II) was 3.1% ( n = 6). The intraday and inter-day precisions for real samples analysis were in the range of 4.4-5.6 and 4.9-5.7%, respectively. The proposed method was applied for the determination of cadmium in baby food samples with satisfactory analytical results. In comparison with other methods, the proposed method is very easy, rapid, simple, and sensitive for determination of cadmium at trace levels in complex matrices. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
36. Inhibitory effect of safranal and crocin, two principle compounds of Crocus sativus, on fibrillation of lysozyme.
- Author
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Joloudar, Tahereh, Saboury, Ali, Shasaltaneh, Marzieh, Bahramikia, Seifollah, Ebrahimi, Mohammad, and Ghasemi, Atiyeh
- Subjects
- *
CROCIN , *SAFFRON crocus , *VENTRICULAR fibrillation , *LYSOZYMES , *THIOFLAVINS - Abstract
A key feature in more than twenty amyloid-related diseases is the aggregation of intra-and/or extracellular misfolded proteins as amyloid fibrils. Therefore, preventing or reversing amyloid aggregation by using of small molecules is considered as useful approaches to the treatment of these diseases. We have evaluated the ability of safranal and crocin, to inhibit amyloid self-assembly of hen egg white lysozyme (HEWL), as an in vitro model system. Structural properties of HEWL in the presence of these compounds were investigated individually using thioflavin T, anilinonaphthalene-8-sulfonic acid fluorescence assays, far-UV circular dichroism and scanning electron microscopy as well as docking method. Our results showed that incubation of HEWL with either crocin or safranal at various concentrations leads a significant inhibition in the rate of amyloid formation. Docking analysis revealed crocin and safranal interact with the central hydrophobic region of lysozyme through van der Waals interaction. Hydroxyl group in crocin through hydrogen bonds connected to the several hydrophilic amino acids of lysozyme, while in safranal there are just one aldehyde group that through hydrogen bonds connected to aspartic acid in lysozyme. It can be concluded that both hydrophobic and hydrophilic groups contribute to lower lysozyme fibril accumulation. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
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