mohammad mahdi salehi

Numerical simulation of turbulent flames with laminar flamelet models is not easily possible under high turbulence intensity conditions. Experimental results and direct numerical simulations show that introducing strain effects in the production of flamelet tables can significantly increase the accuracy of modeling. In this work, implementing the strain effects in the model results in 30 mm increase in the flame height relative to the unstrained model. In this work, a strained flamlet model has been implemented and evaluated in the simulation of turbulent premixed flames. The premixed counterflow flame has been used to produce the flamelet tables. These tables are used in the computational fluid dynamics solver using two reaction progress variables and the presumed probability density function method. The model obtained in this research has been used in Reynolds-Averaged simulation of a turbulent piloted premixed flame in a bunsen burner. This burner utilized a novel approach to highly increase the input turbulence intensity. The results show that the strained flamelet model predicts the flame propagation speed and consequently the flame length, significantly better compared to the unstrained flamelet model.
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The coronavirus disease 2019 (COVID?19) pandemic in Iran has led to a lack of intensive care unit (ICU) facilities. This study examines C?reactive protein (CRP), D?dimer, erythrocyte sedimentation rate (ESR), and troponin in ICU patients with COVID?19 in comparison to COVID?19 patients admitted to the wards in Iran.

In a case–control study, troponin, CRP, ESR, and D?dimer were compared in the case samples of 109 COVID?19 patients admitted to the ICU, and in the control group, 140 COVID?19 patients admitted to the wards.

The mean of CRP (P < 0.001) and D?dimer (P < 0.001) was higher, whereas troponin (P < 0.001) was lower in patients admitted to the ICU, but no significant difference was observed between the values of ESR (P = 0.292) in the two groups.

This study showed that the values of CRP and D?dimer were higher in patients admitted to the ICU, but no significant difference was observed between the values of ESR in the two groups.

Nowadays using 3D printing for prototyping is well known in industrial applications and there are efforts to make functional parts with this technology to reach low volume production markets. By using pellets rather than filaments, the limitations caused by lack of variety of materials can be conquered. Also there will be no need to make a massive part as several divided parts and then glue them together.In this article pellets of ABS, that are well known and functional in industry, are analysed for an extruder to investigate the ability of pellet material extruding. Characteristic specifications of extruder such as operating pressure, screw rotational speed and required torque for rotating the screw are achieved for they are important factors to find out the mechanism for experimental tests and selecting suitable operating parts such as motor and gearbox. At the end, the experimental tests on designed system are done and the result approved the trends of theoretical data.

The role of anti‑phospholipid antibodies (aPLs) in the prognosis of COVID‑19 patients is controversial. In order to prove the role of this factor, the necessary measures such as early initiation of anticoagulants should be started even in the early stages of the disease and in outpatients or the use of other drugs in addition to anticoagulants. We decided to investigate the role of these antibodies in ICU admission outcomes in critically ill COVID‑19 patients.

The case‑control study was carried out in Isfahan, Iran, from March to September 2021. One hundred nine patients in the case group were selected, including patients admitted to the ICU with a COVID‑19 diagnosis. The 140 patients in the control group were selected from hospitalized and outpatients with COVID‑19 with PCR + and pulmonary involvement, similar to the case group without the need for ICU hospitalization. The anti B2GP1 (IgM, IgG) and anti‑cardiolipin (IgM, IgG)) were compared in two groups.

The frequency percentage of patients in the abnormal group of anti‑phospholipid antibodies was about 10% in total. No statistically significant difference in these aPLs in continued measures was observed between the two groups of patients admitted to the ICU and those outside the ICU. Also, in the logistics regression analysis, no significant association was observed.

Therefore, the cause of coagulation in patients admitted to the ICU is not related to these aPLs. This means that aPLs could not be a good predictor of patient admission to the ICU.

In this work, a non-intrusive method is developed to measure the CH* chemiluminescence in a laminar non-premixed flame. In this method, a digital camera and optical band-pass filters are used. CH* chemiluminescence happens in a sharp band around 430 nm, but in the case of a soot formation in the flame, the resulting thermal radiation partly happens in the CH* chemiluminescence band. In this work, two other band-pass filters with central frequencies of 420 and 440 nm are used to estimate the thermal radiation of soot particles near 430 nm. Using this approximation, the effect of the thermal radiation of soot particles on CH* chemiluminescence is removed. Comparing the experimental results in this work with the numerical simulations show that the proposed method can effectively remove the soot thermal radiation when the soot concentration is low. However, as the soot concentration increases, resulting in enhanced thermal radiation, the accuracy of the method decreases.

This research is intended to have a comparative study on the place of altruism in the moral training of John White and Martyr Morteza Motahhari. This is a theoretical research conducted in a comparative analytical method for comparing the theories of moral training of John White and Martyr Morteza Motahhari. This research is aimed at answering the question of what sharing points as well as differences exist between altruism theories of White and Motahhari in the field of moral training. The research came to the result that both scholars settle the issue of altruism in the theory of moral training by adopting a unifying approach. Regarding personal well-being, White places the interests of others and personal interests under the title of well-being, while Motahhari, by presenting his theory of true self and developing the concept of self, emphasizes that the conflicting point must be turned from self and others to self and true self in the moral training. Hence, both thinkers believe in psychological altruism on the basis of weak interpretation, meaning that human beings can do something to benefit others. According to White, the ultimate goal of moral training encompasses the well-being of educators. Motahhari, however, based on Islamic teachings, considers the ultimate goal of moral training as intimacy to God. Moreover, due to the fundamental intellectual-philosophical differences between the ideas of White and Motahhari, White rejects religion and pursues training in a completely liberal-democratic context. On the contrary, Motahhari uses religious teachings to validate his views.

Enterococcus faecalis is a resistant bacterium which is the most abundant species in infected root canals. Photodynamic therapy (PDT) is a method for killing the bacteria with active Oxygen radicals generated in a photosensitizer when exposed to centralized light. Furthermore, as a new method of canal disinfection, a variety of irrigation activation systems have been introduced, one of which is GentleFile (GF) with rotary movements and spiral effects for antibacterial action. This study aimed to compare the effectiveness of the two mentioned methods when used with and without Sodium Hypochlorite in eliminating E. faecalis from infected root canals.

Fifty-eight uniradicular teeth were randomly divided into 4 experimental groups of 14. Two specimens were selected for later scanning electron microscopy in order to screen the procedure steps. In each experimental group, 10 samples were selected to be treated with GF or PDT; 3 of them were selected as positive controls and the other one sample was chosen as a negative control. Experimental groups were as follows: (1) Irrigation activation system, (2) Irrigation activation system + sodium hypochlorite, (3) PDT, and (4) PDT+ sodium hypochlorite. The specimens were then cultured for a bacterial colony count.

The decrease in the bacterial count after the treatment with the irrigation activation system was 99.8% (P = 0.011) and when the system was used with sodium hypochlorite, it was 100% (P = 0.001). The antibacterial effect of PDT was 90.08% (P = 0.011) and it was 99.7% when PDT was combined with sodium hypochlorite (P = 0.011).

All four methods can be administered as complementary methods in root canal disinfection. According to the results of disinfection in the experimental groups of current study it is concluded that integration of new technologies such as activation irrigation system or PDT in Combination with NaOCl ameliorates disinfection of root canal and can provide several advantages in the endodontic outcome.

Conventional hepatitis B virus vaccination fails to achieve efficient protection in about 5%–10% of the world population. Different factors influence the immunogenicity of hepatitis B vaccine. This study aimed to evaluate these factors in health‑care workers.

This was a descriptive study which was implemented among 140 of medical and dental staff working as health‑care workers who were low responder after vaccination entered the study.

Age (>40 years), weight (body mass index >25), immunodeficiency diseases, (primary immune deficiency and immunosuppressant drugs), diabetes mellitus, and smoking were the important factors.

In the high‑risk group of hepatitis B disease, the risk factors of immunogenicity must be evaluated at vaccination and check titers of antibody after vaccination.

Polypropylenes loaded with different alkyl ammonium-modified montmorillonite are prepared to utilize a melt-mixing technique in various ways. Two types of polypropylene and compatibilizer are incorporated to improve the dispersion of various types of nanoclay and the dyeing behavior of the nanocomposites with various disperses, so acid and basic dyes were studied. For the first time, the aim of this study was to investigate the effect of operational and material parameters in dyeing behavior and color buildup of producing nanocomposite due to better understanding of the dyeability mechanism of PP/nanoclay composite. The extent of exfoliation and dispersion of the nanoclay in PP was analyzed by XRD and TEM analytical techniques and the dyeability was studied through color build up and spectrophotometric measurement. The results showed that the mixing condition had not any significant effect on dyeability and lower the molecular weight of polypropylenes and that the compatibilizer causes better dyeability. The most intercalated nanocomposite also showed better dyeability and within various types of dye, disperses dye showed better dyeability. All things considered, it is appeared that between the two mechanisms suggested for dyeing improvement in the PP/nanoclay composite, the dominant mechanism is creating the path.

Mastitis is an inflammatory disorder in breast tissues due to bacterial factors, mycobacterial infections or autoimmune diseases. Idiopathic granulomatous mastitis (IGM) is a form of mastitis which may be affected by systematic diseases such as sarcoidosis, and infectious causes such as mycobacterium and fungus. This study evaluates the efficacy of medical therapy with a combination of corticosteroid and Azithromycin in patients with IGM.

This study is a clinical trial research carried out in Alzahra Hospital (Isfahan, Iran) in 2013 on granulomatous mastitis patients. It was administered 250 mg of Azithromycin per 12 hour and 60 mg of Prednisolone per day within 2 weeks. Next, they took 40 mg/day within 8 weeks, and this dosage was tapered during 6 months and the patients clinically and radiologically followed up. The studied patients were examined within 1 week, 2 weeks, 1 month, 3 months, and 6 months, from the beginning of treatment.

This study investigated granulomatous mastitis patients in Alzahra hospital in 2013. The mean age of these patients was 33.6 ± 8.9, and their age range was 18–56 years old. Among 26 studied patients, 24 persons (92.3%) according to follow‑up the patients by physical examination and sonography responded to treatment of corticosteroid and Azithromycin. The remaining (7.7%) underwent surgery. Treatment periods in case of drug use were respectively, 8.5 ± 0.71 months.

Treatment with corticosteroid and Azithromycin is an effective and appropriate treatment for IGM.

Failure of elastomeric seals due to Rapid Gas Decompression (RGD) under high pressure is a known problem in the oil and gas industry. This phenomenon has significant importance in valves, blow out preventers and compressors. Elastomeric materials because of flexibility, resilience, ability to Self-energize and to compensate for housing tolerances, surface textures and scratches are still the first choice of sealing materials. However O-ring decomposition due to the rapid gas decompression (RGD) is a serious threat for rubbers because of their low tensile strength. In this paper, after studying the effective parameters in design of under pressure seals, design and manufacture of sour gas resistant O-rings applied in high pressure valves of a petrochemical unit (water absorption from sour gas plant of Masjed Soleyman) were investigated. The effect of structural parameters and design variables on the performance of O-rings was also evaluated.

Conventional hepatitis B virus (HBV) vaccination fails to achieve efficient protection in about 5–10% of the world population. Hence, different strategies have been adopted to ameliorate HBV antibody titers. This study aimed to evaluate the concurrent application of tetanus‑diphtheria (Td) and HBV vaccination on hepatitis B surface (HBs) antibody titer in low‑responder healthy individuals.
This was a randomized clinical trial, which was implemented among 140 of medical staff working as health‑care workers assumed as low‑responders. The subjects were randomly allocated to either control or interventional groups. The control and interventional groups received HBV recombinant vaccine while the latter group was also vaccinated through Td. Enzyme‑linked immunosorbent assay was applied to measure HBs antibody (HBsAb) titers just before and 6 months after the last vaccination. All data were entered into SPSS software. Independent t‑test, paired t‑test, and Chi‑square or Fisher’s exact test were applied for data comparison.
Antibody titers of the subjects in the intervention and control groups soared from 49.08 ± 20.08 IU/L to 917.78 ± 204.80 IU/L and from 46.95 ± 18.55 to 586.81 ± 351.77 IU/L, respectively (both P Concurrent application of Td and HBV vaccine could effectively enhance protective levels of HBsAb titers in low‑responder individuals.

In this article various pipes used for transporting of gas are introduced and pros and cons of each one are elucidated. The pipes are categorized in three different subgroups including metallic, polymeric and metallic-wire reinforced polymeric pipes. Metallic-wire reinforced polymeric pipes are nominated as the best option for usage in high pressure pipelines transporting natural gas. As a result, some information about major manufacturers of this kind of polymeric pipes, raw material, production process and metallic-wire orientation are presented. Finally, from economical point of view, some calculations are done to estimate required amount of polymer and metallic-wire to manufacture such pipes. It is also possible to compare their manufacturing cost with usual metallic and polymeric pipes.

The main objective of the present work was to synthesis polyamide 6 through anionic polymerization of ε-caprolactam in an internal mixer. The reaction time and the rheological properties of samples during the polymerization were studied. The samples were characterized by Thermo Gravimetry Analysis (TGA), Differential Scanning Calorimeter (DSC) and FT-IR spectrometer. The melt flow behavior and viscoelastic properties of the samples were studied by using a Rheometric Mechanical Spectrometer (RMS). The polymerization reaction was found to be very fast such that it completed within 6 minutes as could be detected by following the mixing torque which reached to a steady state after passing a maximum. These results suggest that there is a reaction time above which the viscoelastic behavior of the samples almost remained unchanged, while the viscosity and elasticity of the samples continue to decrease with polymerization reaction time as a result of thermochemical degradation.

Hepatitis B virus (HBV) fails to produce appropriate immune responses in some healthy individuals; thus, different strategies have been adopted to promote immune responses. The current study aimed at evaluating the efficacy of HBV vaccine coadministered with tetanus-diphtheria (Td) vaccine compared with HBV vaccine in healthy individuals through measuring hepatitis B surface antibody (HBsAb) levels. This was a randomized controlled clinical trial, which was implemented in Isfahan, Isfahan Province (Iran) in 2013. One hundred and forty healthy individuals, whose HBsAb titers were less than 10 IU/L were recruited. The subjects were randomly assigned to either in intervention or control trials. The control group received 40 µg of recombinant HBV vaccines intramuscularly injected at 0, 1, and 6 months; however, the intervention group was simultaneously vaccinated by Td with the first dose of HBV vaccine. HBV antibody levels (titer) were measured before the vaccination and 6 months after the last vaccination. Antibody titers of the subjects in the intervention and control groups increased from 5.07 ± 2.9 IU/L to 744.45 ± 353.07 IU/L and from 4.45 ± 3.4 IU/L to 589.94 ± 353 IU/L, respectively (both P < 0.001). Also, the mean difference of antibody titer was significantly different between the two groups (P = 0.011). Td vaccination can be applied as a feasible approach to promote efficient and persistent immunity in healthy individuals with insufficient HBsAb titers.

In this work, ternary polymer blends based on polypropylene (PP)/ polyethylene terephthalate (PET) /poly(styrene-b (ethylene-co-butylene)-b-styrene) (SEBS) triblock copolymer and a reactive maleic anhydride grafted SEBS (SEBS-g-MAH) at various compositions were prepared by co-rotating twin screw extruder. The effects of PET, SEBS and SEBS-g-MAH compatibilizer on morphology of the blends were examined by scanning electron microscopy (SEM). The blends morphology was also estimated by some predicting methods, however, SEM results revealed some contrasts between results of predicting methods and the real morphology. Population of individual and core-shell particles as well as average diameter of the rubber-based cavities is extremely dependent on SEBS, SEBS-g-MA and PET content. Mechanical inspection tests showed that in comparison with the pure PP, addition of SEBS/SEBS-MA causes an increase in the impact strength of the system. Keeping other parameters constant, with increase in SEBS rubbery phase, the core-shell morphology was affected and the impact strength increased consequently. On the other hand, increase in PET content results in modulus increase and the impact strength decrease. Finally, the optimum processing conditions for compounding ternary PP/PET/SEBS blends were achieved.

Soils reinforced by geogrids exhibit different behavior, compared to unreinforced soils, due to having high tensile strength elements. In this paper, the main factors influencing the behavior of such reinforced soil under a strip footing are investigated and discussed. A numerical model for the reinforced soil is developed using FLAC-2D finite difference software. The model is calibrated, and then different important factors such as width, number, distance and depth of the first layer of geogrid are studied and evaluated. The qualitative behavior of the reinforced soil under different conditions of reinforcement elements is also studied in this work. The results of several analyses show that the optimum depth of the first layer of geogrid is one fourth of the footing width, and the other layers would have effective role up to 1.75 times of the width. Also, the distance between geogrid layers needs to be decreased in case of increasing their number, whose optimum value is less than half of the footing width. The geogrid width and its tensile strength have considerable effect on the behavior of the reinforced soil, when geogrid layers are in optimum position.

Idiopathic granulomatous mastitis (IGM) is defi ned as a rare, infl ammatory, chronic and benign disease mimicking malignant hyperplasia of mammary glands. Th ere is no defi nitive therapeutic strategy for IGM; nevertheless, some approaches can be exploited as benefi cial strategies. In this study, the surgery strategy was compared with coincident treatment with azithromycin and corticosteroid in IGM patients.

Th is study was implemented as clinical trial during 2011-2013 in Isfahan, Iran. Th e target population comprised women whose IGM was substantiated. Th e medical group consisted of 20 patients, which were compared with a historical control group treated through surgical approach. Surgical group comprised 39 patients. Partial mastectomy was implemented in the surgical group whereas treatment protocol comprising azithromycin and prednisolone administered in medical group. Recurrence of mass was followed for 12 months. Fischer exact test, Chi-square test, Mann-Whitney and regression tests were applied for statistical analysis. Th is study was registered in Iranian Registry of clinical trial (IRCT number: IRCT 2013123015999N1).

No signifi cant diff erences were recognized in side of lesions, lymphadenopathy, fever and pain; however, number of abscesses, number of lesions and size of lesions were signifi cantly higher in the surgical group (P < 0.0001). Furthermore, probability of relapse correlated with the number of lesions, (odds ratio = 24.67 confi dence interval [CI] = 2.2-269.3), whereas methods of IGM treatment did not contribute to the likelihood of relapse (odds ratio = 12.5 CI = 0.52-299).

Th is clinical trial demonstrated that pharmaceutical treatment has appropriate effi cacy, in treatment and prevention of IGM relapse. Moreover, this study presented hazf gardad number of the lesions as the most appropriate criteria for IGM prognosis, thus the probability of relapse decreases whether earlier IGM recognizing could be implemented.