m. rahbar

This study presents the optimized shape and thickness of thin continuous concrete shell structures, minimizing their weight, deflection, and elastic energy change while meeting the performance requirements and minimizing material usage. Unlike previous studies that focused on single-objective optimization, this research focuses on multi-objective optimization (MOO) by considering three objective functions. This combination of objective functions has not been reflected in previous research, distinguishing this study. The computational design workflow incorporates a parametric model, multiple components for measuring objective functions in the grasshopper of Rhino, and a metaheuristic algorithm, the non-dominated sorting multi-objective genetic algorithm (NSGA-II), as the search tool, which was coded in Python. This workflow allows us to perform form-finding and optimization simultaneously. To demonstrate the effectiveness of this metaheuristic algorithm in structural optimization, we applied it in a case study of a well-known shell designed using the physical prototyping hanging model technique. Interpretations of samples of optimized results indicate that although solution 1 weighs nearly the same as solution 2, it has less deflection and strain energy. Solution 3, with a three-fold mass, has significantly less deflection and strain energy than solution 1 and solution 2, with deflection reductions of over 50 and 17%, respectively. Solutions 3 and 4 show better deflection and strain energy performance. Furthermore, a comparison of the MOO results with the Isler shell revealed that this method found a solution with less weight and deflection while being stiffer, confirming its practicality. The study found that MOO is a reliable method for form-finding and optimization, generating accurate and reasonable results.

despite the many benefits of dental implants, their cost remains a controversial issue. No study in Iran evaluated the costs and benefits of this treatment accurately, so the present study aimed to investigate the economic burden of implant surgery on the urban households of Ardabil province in 2021.

in this descriptive-analytical, cross-sectional study, the economic burden of implant surgery was estimated using the cost of illness method and human capital method. In this study, based on the content and purpose, the prevalence-based approach was used and a suitable checklist was prepared. The statistical population was patients referred to public and private centers providing dental services in Ardabil city. The sample size was calculated to be 160 people and a random sampling method was used for sampling. . Data analysis was done with SPSS version 21 software and Excel software.

The results of the investigation showed that the total cost of implant surgery per unit was (118680744 Rials), 82.11% of these costs were related to direct medical costs, 10.92% were related to non-medical direct costs, and 6.97% were related to indirect medical expenses. Also, the economic burden of implant surgery on Ardabil society was estimated at 71 trillion 467 billion 62 million 235 thousand 635 Rials.

Implant surgery imposes a huge cost on society, so by planning the essential preventive tooth decay strategy, the economic burden imposed by implant surgery on the society of Ardabil can be reduced in the future.

Contaminated foods with Shiga toxigenic serotypes of Escherichia coli (STEC) can cause diarrhea and severe diseases in consumers. The aim of this study was to investigate frequency of Shiga toxigenic Escherichia coli serotypes and their antibiotic resistance patterns in vegetable samples from Tehran, Iran.

In this study, a total of 97 vegetable samples from 22 urban areas of Tehran, Iran, were investigated, July 2018 to March 2019. To identify Shiga toxigenic Escherichia coli strains, standard method of enrichment and culture in selective media and polymerase chain reaction for verifying presence of stx1 and stx2 genes were used. Presence of eae and ehxA genes was investigated in Shiga toxigenic Escherichia coli isolates. Antibiotic resistance was assessed using disk diffusion method for 15 antibiotics and the multidrug resistance phenotype was assessed.

Shiga toxigenic Escherichia coli strains were isolated in 14/4% of vegetable samples (stx1, stx2, stx1/stx2 of 8, 1 and 5%, respectively). Presence of eae and ehxA genes was shown in 1 and 2% of Shiga toxigenic Escherichia coli isolates, respectively. The highest resistance was detected to trimethoprim-sulfamethoxazole (100%), erythromycin (73.33%) and tetracycline (85.7%) and the lowest against meropenem (0%) and imipenem/ceftazidime (7/7%).

In this study, contamination of vegetables with multidrug resistant Shiga toxigenic Escherichia coli was verified in Tehran, Iran. Further studies on human samples can clarify this contamination.

Salmonella is considered as a main cause of community-acquired diarrhea in humans, however, sources of the multi-drug resistant (MDR) strains and their link with the disease are not well known.

This study aimed to investigate the frequency, serogroup diversity, and antimicrobial susceptibility patterns of Salmonella strains in poultry meat and stool samples of patients with community acquired diarrhea in Tehran.

We compared the frequency of non-typhoidal Salmonella serogroups, the similarities of their resistance patterns to 10 antimicrobial compounds, the prevalence of extended spectrum β-lactamase (ESBL) and ampicillinase C (AmpC) genetic determinants, and class 1 and 2 integrons in 100 chicken meat and 400 stool samples of symptomatic patients in Tehran during June 2018 to March 2019.

Salmonella was isolated from 75% and 5.5% of the chicken meats and human stool samples, respectively. The chicken meat isolates mainly belonged to serogroup C (88%, 66/75), while the human stool isolates were mainly related to serogroup D (59.1%, 13/22). The MDR phenotype and the most common rates of resistance to antibiotics, including tetracycline, trimethoprim/sulfamethoxazole (TS) and azithromycin, were detected in 4.5% and 45.3%, 59% and 13.6%, 43% and 9.1%, 42% and 9.1% of the human stool and chicken meat samples, respectively. Carriage of blaCTX, blaSHV, and blaPER genes in the meat isolate with ESBL resistance phenotype and blaACC, blaFOX, and blaCMY-2 among the 7 meat strains with AmpC resistance phenotype was not confirmed using polymerase chain reaction (PCR). High prevalence of class 1 and 2 integrons was characterized and showed a correlation with resistance to TS and chloramphenicol.

These findings showed a lack of association between chicken meats and human isolates due to discrepancy between the characterized serogroups and resistance phenotypes.

The present study aimed to determine the optimal concentration of three anaesthetics, name MS222, ketamine, and tobacco extract, in grass carp juveniles (107.78±22.11 g body weight and 226.74±13.06 mm total body length). Treatments were as follows: 100 mg L-1 of MS222 (control group), 5.5, 8, 11, 18.5, and 22 mg L-1 of ketamine, and 10, 13.33, 20, 26.27, and 40 mg L-1 of tobacco extract. In addition, changes in blood and biochemical parameters were measured at different concentrations. Considering the anaesthesia induction and recovery durations times, the optimal concentration for anaesthesia of studied substances was obtained as follows: 100 mg L-1 of MS222 (139.00±20.00 seconds), 18.5 mg L-1 of ketamine (140.10±20.20 seconds), and 40 mg L-1 of tobacco extract (174.00±20.09 seconds). Based on the results, the shortest recovery time from anaesthesia was observed at 26.27 mg L-1 of tobacco extract (870.00±5.3 seconds) and 8 mg L-1 of ketamine (967.00±5.5 seconds), respectively. The results indicated that the anaesthesia induction and recovery duration was dependent on the concentration of anaesthetics. Moreover, significant differences were observed between the three anaesthetics in terms of blood parameters. The study findings also revealed a significant difference between treatments in biochemical parameters (cortisol, glucose, and lactate).

 Perivalvular and valve involvement are prevalent in patients with end-stage renal disease (ESRD), especially in younger patients compared with normal population. Kidney transplantation improves the prognosis of these patients. Patients with cardiac valvular disease is also be improved following kidney transplantation.

 To evaluate the impact of renal transplantation on the severity of mitral regurgitation (MR).

 We studied 95 kidney transplantation candidates in Sina Hospital. The patients underwent echocardiography preoperatively and at the 3rd, 6th, and 12th months post-operatively.

 Pre-operatively, the average MR fraction was 30%; MR volume 30 mL/beat; mitral valve mean gradient 1.8 mm Hg; mitral valve area 4.6 cm2; and mitral annular size 3 cm. No significant difference was observed among the measurements made at the 3rd, 6th, and 12th months post-operatively.

 There was no significant association between the variables measured pre- and post-operatively. The reason might be the fact that patients with ESRD in Iran do not have to expect long transplant waiting lists and dialysis cannot affect their heart adversely.

Oral candidiasis is the most common fungal disease, and it is often considered as a local opportunistic infection. Oral candidiasis is usually treated with local use of antifungal medications. Since probiotic bacteria have the ability to inhibit the growth of pathogens and modulate human immune responses, they could provide new possibilities in antifungal therapy. The aim of the present study was to examine the effect of probiotic yoghurt on the frequency of salivary candida. This randomized double-blind crossover clinical trial involved 34 healthy adults divided to two groups: 17 subjects in case group (probiotic yoghurt) and 17 subjects in control group (regular yoghurt). At the beginning of the experiment and after 3 weeks of intervention (consumption of regular or probiotic yoghurt), saliva samples were collected from both groups and candida colonies were counted. After a two-week wash out period, the groups were interchanged (crossover study design), and the sampling process was repeated. The data were analyzed using Mann-U-Whitney and Chi-square tests. The level of significance was set at p<0/05. Variations of salivary candida equaled 1.8±9.3 cfu/ml in regular yoghurt group and -3.8±7.9 cfu/ml in probiotic yoghurt group (p=0.01). The amount of salivary candida decreased in 47% of the cases in probiotic yoghurt group and in 29.4% of the cases in regular yoghurt group (p=0.07). The results of the present study showed that short-term consumption of probiotic yoghurt decreases the frequency of salivary candida colonies after 3 weeks.

Stressful life events are seen frequently, prior to suicide in persons who attempted. This study was done to survey problematic life events prior to suicide attempt in patients who had been admitted in emergency ward of Razi Hospital in Rasht 2001. To achieve this goal , 173 patients who had been admitted due to suicide attempt were interviewed by two trained male and female general practitioner .For collection of data , a questionnaire was used. Findings of investigation showed that the most common life event was family problem (76.1%). problem in interpersonal relationships (25%), especially break in love , financial problems (12.1%) death of close friends or relatives(4%),somatic illness(3.4%), academic problems(2.3%) and legal problems (1.1% )were less frequent. Significant statistical relationships were found between life evens of death of close friends or relatives (p=0.02), financial problems(p=0.04), problem in interpersonal relationships (p<0.01) with age groups and financial problems (p<0.001),job problems (p<0.0001), problems in interpersonal relationships(p<0.02)with sex and death of close friends or relatives with academic level and job problems(p<0.02), problem in interpersonal relationships (p<0.01),family problems (p<0.01), academic problems (p<0.03) with marital status financial problems with place of living (p<0.01). It is concluded that, problematic life events prior to suicide attempt in two sexes, age groups, different academic levels, marital status and place of living was vary and significant relationships were seen between them. More study about this relationships and their patterns for identifying of high risk groups in front of problematic life events and presenting appropriate programs for reducing suicide attempt is recommended.

We report a case of a 40 year old man with portal hypertension caused by a splenic arteriovenous fistula that was diagnosed at laparotomy. He presented with bleeding esophageal varices and was initially treated by sclerotherapy. At laparotomy, portal pressure was 40 cmH20 but fell to 20 cm H20 after the fistula was treated with splenectomy. All symptoms disappeared shortly after operation and the patient has remained well for the past two years.

In this study, twenty-five strains of Mycobacterium tuberculosis resistant to isoniazid (INH) were isolated from patients with tuberculosis (TB). Nine strains (36%) were found to be virulent in guinea-pigs [root index virulence (RIV» 1 ]. The remaining sixteen strains (64%) were non-virulent (RIV <1). Of the nine strains resistant to INH as well as virulent to guinea-pigs, eight of them were found to be catalase positive and only one strain was catalase negative, whereas the remaining sixteen INH resistant strains were catalase negative. A strong association was observed between INH resistance and catalase positivity and virulence (p<0.0001 chi-square test). This study supports the hypothesis that catalase has an important role in the virulence of INH-resistant strains of M tuberculosis.