Showing 13 results for Ebrahimzadeh
Volume 3, Issue 2 (, (Articles in Persian) 2012)
Abstract
In this study, first using documentary research method, the nature of language in the web-based electronic communication, besides different methods of improving communicative and linguistics competence in teaching languages online, were investigated. Then considering the importance of language faculties' familiarity with the role of computer-based teaching in the development of linguistic competence and communicative skills necessary for translating or teaching all foreign languages (esp. Persian to non-natives), a descriptive survey method was used to investigate the familiarity of foreign language faculties with the strategies and technologies used in e-teaching-learning process applied in teaching languages online. The results of the 68 questionnaires filled in by English, French, German and Persian faculties of seven universities offering classical and virtual programs indicated that most of language faculties are not familiar with web-based strategies and techniques in teaching or learning foreign languages. Considering the need of our country for the experts who are able to communicate with the scientific scholarly networks in the world to obtain or transfer related knowledge and those who are able to use at least one international language of their fields thoroughly, planning an online faculty training program can be an essential measure to improve teaching or translating foreign languages at the academic level and also lead Persian language to find its proper position in the cultural, educational and scientific world networks.
Volume 3, Issue 2 (Number 2 - 2001)
Abstract
Leaf and root explants from 10 to 20 day– old seedlings of Plantago lanceolata, were
cultured on MS, MSH, NT and B5 basal media with various concentrations of different
plant growth regulators. The best callus induction was obtained with 0.4 mgl-1 2,4-D in
MSH I with 400 callus index. Callus growth was significantly stimulated (P=0.05)with 0.8
mgl-1 2,4-D and 0.1 mgl-1 Kin in MSH II, with 799 mg fresh weight and 79 mg dry weight.
A higher production of mucilage was obtained in MSH II. The mucilage content of different
media varied from 10.40 to 14.73% dry weight. Perusal of the data reveals significant
differences with regard to the total mucilage content. Callus has nearly 3 times and 1.5
times more mucilage than seeds and leaf and root parts respectively.
Volume 4, Issue 1 (Winter 2024)
Abstract
Specialization and turning away from macro systematizations in philosophy can be commonly seen as relatively common practices of analytic philosophers. However, the contemporary philosopher Nicholas Rescher, as one of the exceptions to this tradition, is not only alien to this pattern but even considers it a methodological flaw. This article deals with the philosophical foundations of this point of view, the philosophical methodology derived from it, and its strategic methods by researching Rescher's works. Relying on his epistemological foundations (especially coherentism), Rescher believes that we should solve philosophical problems with a holistic approach and by considering the entire field of philosophy. Although Rescher's type of systemization is safe from some criticisms due to not neglecting the details of the system components, it still needs to be corrected or completed from a methodological perspective. One of the most important gaps in this point of view is the lack of a regulated model in managing the balance between comprehensiveness and specialization, as well as in determining the boundaries of maximality of the system.
M. Naderi Jolodar, A. Roohi, M. Ebrahimzadeh,
Volume 7, Issue 1 (Winter 2018)
Abstract
Aims: Being important both economically and in terms of protection, Luciobarbus capito is at risk of extinction. There are very few studies about the fish of Shahid Rajaee dam and the Tajan River. A significant number of Luciobarbus capitos is present in the dam and upstream. The present study was conducted with the aim of evaluating the growth characteristics and nutritional strategies of Luciobarbus capito in reservoir behind the Shahid Rajaee dam, Sari.
Materials & Methods: The present experimental study was carried out on 180 Luciobarbus capitos in Shahid Rajaee dam, Sari during 4 seasons of 2014 to 2015. The samples were fixed in formalin 10% and the biological and nutritional factors related to growth were investigated. The data were analyzed with SYSTAT 9 and Excel 2003 software.
Findings: The sex ratio of males to females was 1.14/1. The growth pattern of this allometric species was negative (w=0.015×L2.888; b=2.888). In males, allometric was positive and in females, allometric was negative. The mean length and weight of male and female had a significant difference (p<0.05), and the relationship between length and weight in fish was progressive. This species approaches the maximum predicted length with a growth rate of 0.1; the maximum estimated length for fish was 138.6 cm. Nutritional behavior index for under 4 years group showed a herbal diet (RLG=2.4±0.1) and, after puberty, it was inclining to a whole foods diet (RLG=1.2±0.6).
Conclusion: The allometric growth pattern is a negative for Luciobarbus capito, and in all seasons, it has a whole foods diet.
Volume 8, Issue 3 (Summer 2022)
Abstract
Backgrounds: Toxoplasma gondii is a zoonotic parasite of increasing concern to humans and animals. Considering the side effects of drugs used to treat toxoplasmosis, it is essential to find alternative drugs.
Materials & Methods: In this study, colchicine and propranolol at four concentrations (1, 5, 10, and 15 µg/mL) were added to the RPMI medium containing peritoneal macrophages and incubated for 60 min, Then tachyzoites were added to the medium, and the efficacy rates of colchicine and propranolol in inhibiting tachyzoites entry into macrophages were evaluated after 30 and 60 min. For in vivo assay, one group received no drugs, and the second group was treated with colchicine and propranolol at different concentrations for different durations.
Findings: The in vitro experiment showed that treatment with 15 mg/mL of colchicine and propranolol for 60 min following tachyzoites addition was the most efficient method to inhibit tachyzoites penetration, indicating the efficacy rates of 80.20%±1.20 and 89.97%±1.30, respectively (p< .05). Based on the in vivo test, pretreatment with 2 mg/kg of colchicine one hour before tachyzoites injection had the best inhibitory effect (70.32%±4.07). Also, pretreatment with 2 mg/kg of propranolol 90 min before tachyzoites injection (78.54%±1.99) induced the best inhibitory effect (p< .05).
Conclusion: According to the results, colchicine and propranolol could inhibit tachyzoites entrance into nucleated cells in vitro and in vivo. In this study, the most efficient concentrations and times for using these substances were determined.
Volume 9, Issue 2 (Spring 2018)
Abstract
Aims: Alchemilla L. genus (Rosaceae) has various biological activities such as anti-inflammatory, anticarcinogenic, antioxidant and antimicrobial. The aim of the present study was to investigate antioxidant activity and free radical scavenging of the extract obtained from Alchemilla persica by percolation, polyphenol fraction, and ultrasonic methods.
Materials and Methods: In the present experimental research, Alchemilla persica was used and percolation, polyphenol, and ultrasonics methods were used for extraction and the antioxidant activities of the extracts were determined by different tests, including 1, 1-Diphenyl-2-picrylhydrazyl (DPPH), nitric oxide scavenging activity, Iron chelating activity, and reducing power. Total phenolic and flavonoid content were measured by the Folin Ciocalteu and AlCl3 methods, respectively. The data were analyzed by SPSS 22 software, using one-way ANOVA and tukey test.
Findings: In DPPH radical scavenging activity, the polyphenol extract had a significant different with other extracts (p=0.001). Polyphenolic extract showed higher reducing power than other extacts and Vitamin C (p=0.001). Percolation extract had higher amounts of total phenolic and flavonoid content than other extracts.
Conclusion: Polyphenolic extracts have the highest DPPH, nitric oxide scavenging activity, Iron chelating activity, and reducing power compared to ultrasonic and percolation methods. Aerial parts of Alchemilla persica extracts have high levels of antioxidant activity including phenols and flavonoids.
Volume 9, Issue 3 (Summer 2021)
Abstract
Aims: Eating disorders are making a point of challenge for health-related researches. Using big data for this type of researches can effectively help researchers use a beneficial resource of information worldwide in real-time. This study aimed to introduce a more accurate index for analyzing food-related data and making relations between people's opinions and the prevention treatments for eating disorders.
Instrument & Methods: In this data mining study, more than 2 million eating-related tweets were collected from Twitter in 2017 and analyzed by novel methods for big data research. Three main indicators (Basic-sentiment-rate, Health-rate, and Relation-rate) were used to predict if every user is more likely to have a healthy or unhealthy diet. Finally, these parameters were normalized, clustered, and combined to obtain an overall sentiment rate.
Findings: Location and gender were estimated as effective indicators making the relationship between peoples' opinion and prevention treatments for eating disorders. Some combinations of factors were also considered influencing indicators when applied together, such as gender+age and gender+location.
Conclusion: Punishment/reward combination criteria that are predicted with both gender and location data by FSR index is the most effective factor in making the relationship between peoples' opinion and prevention treatments for eating disorders.
Volume 10, Issue 3 (Summer 2024)
Abstract
Background: In this comprehensive study, the prevalence of sepsis, a potentially life-threatening condition, was investigated among 477 patients displaying sepsis symptoms.
Materials & Methods: A detailed questionnaire was used to capture the patients' demographic information and clinical treatment outcomes.The E-test method was employed to determine the susceptibility of Gram-positive bacteria to vancomycin and Gram-negative bacteria to cefepime, ceftriaxone, and imipenem.
Findings: Among the participants, 40 patients (8.6%) were diagnosed with septicemia, a condition whose prevalence significantly increased with age (p= .001). Out of 40 patients with positive blood cultures, 14 (35%) were infected by Gram-positive bacteria, while 26 (65%) were infected by Gram-negative bacteria. Acinetobacter lwoffii and Staphylococcus epidermidis were identified as the most common causes of sepsis among Gram-negative (30.7%) and Gram-positive (57.1%) bacteria, respectively Gram-negative bacteria exhibited the highest resistance to ceftriaxone (38.4%) and the highest susceptibility to imipenem (84.6%) in both laboratory and clinical settings. Gram-positive bacteria demonstrated the high susceptibility to vancomycin (78.5%), with only four patients exhibiting resistance to vancomycin in both laboratory and clinical settings. Encouragingly, there was a 77.5% concordance between laboratory and clinical antibiotic susceptibility testing results.
Conclusion: Based on these findings, vancomycin and imipenem are recommended as the preferred antibiotics for Gram-positive and Gram-negative bacteria, respectively. Given the high concordance (77.5%) between laboratory and clinical results, it is suggested to perform antibiogram test using E-test method on blood culture isolates in septicemia cases to guide appropriate antibiotic treatment.
Volume 13, Issue 2 (1-2023)
Abstract
Poly-γ-glutamic acid (γ-PGA) is a beneficial, biocompatible, and biodegradable biopolymer. These properties have been led to the development of the use of this compound in various industries such as bio-medicine, biopharmaceutical, biotechnology, and tissue engineering. The limitation of the industrial development of γ-PGA is the high cost of its production. To reduce γ-PGA production costs, various strategies are used, such as culture medium optimization using inexpensive compounds, the development of efficient cultivation processes of batch and fed-batch. In this research, first, an efficient batch culture medium was developed to produce γ-PGA of
Bacillus licheniformis ATCC 9945
a. Then, the γ-PGA production increased by the pulsed feeding method and its optimization. By optimal culture medium development, the production of this product in batch culture was increased from 11 g/L to 47 g/L. Then, using the optimized pulsed feeding strategy of citrate (γ-PGA precursor), γ-PGA production was increased to 59.5 g/L, which is one of the highest production values reported with this strain. To optimize two-pulse feeding, the effect of feeding times, stock citrate solution concentration, and time of calcium and manganese solutions addition on γ-PGA production were investigated and optimized. Finally, FTIR confirmed the chemical structure of poly gamma glutamic acid, and the study of γ-PGA morphological properties with SEM showed a nanostructure ideal for biological applications.
Volume 15, Issue 3 (10-2012)
Abstract
Objective: Biodegradable polycaprolactone/starch composites can be used for bone tissue engineering applications. The effect of the ratio of components on composite properties is of tremendous importance. Methods: Polycaprolactone/starch composite of 80/20 and 70/30 ratios were fabricated by dissolving them in chloroform followed by evaporation of the solvent. Results: The composites were characterized by fourier transform infrared spectroscopy. Their bioactivity was evaluated by studying the apatite formation ability after immersing the specimens in simulated body fluid. The results of compressive test on samples showed that the composite’s modulus and strength approximated that of human trabecular bone. Mass loss in distilled water and starch degradation rate in PBS was evaluated, which showed that the starch ratio was effective in composite degradation. MTT analysis and alkaline phosphatase levels showed that this composite had no toxicity and could increase G-299 cell line osteoblastic activities. Conclusion: The increase in cellular osteoblastic activities and the ability for apatite formation on the composite surface, in addition to the polycaprolactone/starch samples' mechanical properties shows their capability to be used as substitutes for bone. Because this composite degradation rate is controlled by changing the starch ratio, it has the potential for use in bone tissue engineering applications. Samples that have a 70/30 ratio are considered optimal due to their enhanced cellular response and better mechanical properties.
Volume 20, Issue 136 (June 2023)
Abstract
The survival of probiotics in food products face various challenges during the production process. One of the emerging processes in the production of food products is 3D printing. The effect of this process on the viability of probiotics has not been studied so far. In this research, the effect of micro-encapsulation on cell viability during the process of 3D printing and cookie baking (based on waste from confectionery products) was investigated. First, the conditions for the production of micro-capsules were optimized by modulating the percentage of sodium alginate and calcium chloride solutions. Then, the effect of micro-encapsulation with different concentrations of micro-capsules (10, 5, 0% w/w) on the firmness of the dough texture was also investigated as an important factor in the printability of the dough. Finally, the cell viability was evaluated during the printing and baking process (150°C and 180°C for 10 minutes). The results of the microscopic images showed that with the increase in the concentration of sodium alginate and calcium chloride solution, the uniformity and sphericity of the micro-capsule increases. The efficiency of alginate-based micro-encapsulation in this method was 89.41%. The optimal concentration of micro-capsules in order to have the desired printability of baked dough, was reported as 5% w/w. Microencapsulation increased the survival rate of probiotics during 3D printing and baking. The survival percentage of microencapsulated probiotics (T2) after 3D printing and baking (150°C temperature) was 96.86% and 62.58%, respectively. Meanwhile, the survival percentage for the sample containing free cells (T1) was reported 60.77% and 43.05%, respectively. However, no viable probiotic cells were observed in both free and encapsulated cells conditions at 180°C.
Volume 22, Issue 3 (5-2022)
Abstract
In this paper, a finite element analysis of the behavior of embedded CFST columns to the foundation under axial-lateral combined loading. First, the proposed finite element model is compared and analyzed by the experimental results of previous research, which showed that the local damage, failure patterns and hysteresis curves were consistent. A detailed parametric study to evaluate the cyclic behavior of embedded CFST columns to the foundation with the characteristics, the ration diameter to thickness, embedded length, compressive strength and connection conditions CFST column to the foundation. Based on the parametric study, the values of stiffness, strength, ductility and energy for the studied specimen have been calculated. The results showed that using the proposed finite element model, weak cyclic behavior for CFST connection to the foundation in the conditions of connection with the base plate and better cyclic behavior for the CFST column and its connection to the foundation in the embedded conditions is obtained. In addition, the hysteresis behavior of the CFST column connection with the embedded stiffener plate is much better than the embedded connection without the stiffener. The rings stiffener of the hysteresis diagram changes compact condition with increasing concrete strength. In addition, lateral strength, lateral stiffness, ductility performance and cumulative energy dissipation also increased in compact specimens with increasing confine concrete. The failure modes of the CFST connection to the foundation with the base plate are the same as the embedded connection mode without the stiffener and with the ring stiffener. The failure modes in these three modes are from the connection as a tearing steel pipe at the end of the column. In the case of an embedded connection with a longitudinal stiffener, it is a diagonal crack of the concrete on the foundation. Lateral strength, lateral stiffness, ductility performance, and cumulative energy also increase with increasing steel pipe thickness. CFST column burial conditions with hardeners have a positive effect on the hysteresis rings of CFST connection to the foundation, and this type of connection has been able to significantly improve lateral strength, lateral stiffness, ductility and dissipative cumulative dissipation energy.
Volume 23, Issue 4 (7-2021)
Abstract
In this research, production of a probiotic drink based on jujube extract by means of fermentation with Lactobacillus plantarum and Lactobacillus delbrueckii as probiotic lactic acid bacteria was studied. The fermentation was performed for 72 hours at 37°C. The changes in microbial population, pH and titratable acidity as well as sugar and organic acid metabolism during the fermentation period were evaluated. In addition, before and after fermentation, the changes in total phenolic compounds and antioxidant activity in the extract were also investigated. Eventually, different drink formulations were developed employing fermented and non-fermented jujube extract, carbonatation, and sour cherry concentrate. Then, sensory properties of the formulated drinks were evaluated. Appropriate growth of L. plantarum and L.delbruckii resulted in an increase in acidity to 1.86 and 1.75, and a decline in pH to 3.4 and 3.56, respectively, after 72 hours. Glucose and fructose were significantly consumed by the strains. Citric acid concentration dropped to 1.12 and 5.8 g L-1 in the extract fermented by L. plantarum and L. delbrueckii, respectively, after 72 hours. At the end of fermentation, 23.8 and 11.4 g L-1 lactic acid was produced by L. plantarum and L. Delbrueckii, respectively. The contents of phenolic compounds and antioxidant activity in jujube extract after fermentation were significantly increased.The results of sensory evaluation of different drink formulations showed that the carbonated drink containing jujube extract fermented by L.plantarum mixed with sour cherry concentrate obtained the highest score among different drink formulations.
