Portfolio Selection Problem Using CVaR Risk Measures Equipped with DEA, PSO, and ICA Algorithms

Investors always pay attention to the two factors of return and risk in portfolio optimization. There are different metrics for the calculation of the risk factor, among which the most important one is the Conditional Value at Risk (CVaR). On the other hand, Data Envelopment Analysis (DEA) can be used to form the optimal portfolio and evaluate its efficiency. In these models, the optimal portfolio is created by stocks or companies with high efficiency. Since the search space is vast in actual markets and there are limitations such as the number of assets and their weight, the optimization problem becomes difficult. Evolutionary algorithms are a powerful tool to deal with these difficulties. The automotive industry in Iran involves international automotive manufacturers. Hence, it is essential to investigate the market related to this industry and invest in it. Therefore, in this study we examined this market based on the price index of the automotive group, then optimized a portfolio of automotive companies using two methods. In the first method, the CVaR measurement was modeled by means of DEA, then Particle Swarm Optimization (PSO) and the Imperial Competitive Algorithm (ICA) were used to solve the proposed model. In the second method, PSO and ICA were applied to solve the CVaR model, and the efficiency of the portfolios of the automotive companies was analyzed. Then, these methods were compared with the classic Mean-CVaR model. The results showed that the automotive price index was skewed to the right, and there was a possibility of an increase in return. Most companies showed favorable efficiency. This was displayed the return of the portfolio produced using the DEA-Mean-CVaR model increased because the investment proposal was basedon the stock with the highest expected return and was effective at three risk levels. It was found that when solving the Mean-CVaR model with evolutionary algorithms, the risk decreased. The efficient boundary of the PSO algorithm was higher than that of the ICA algorithm, and it displayed more efficient portfolios.Therefore, this algorithm was more successful in optimizing the portfolio

Clinical features, management and in-hospital outcome of ST elevation myocardial infarction (STEMI) in young adults under 40 years of age

Objectives: This study was designed to evaluate the demographic and clinical findings and in-hospital management and outcome in patients with an acute ST-segment elevation myocardial infarction (STEMI). Material and methods: By review of the Cardiovascular Tehran Heart Center Registry (CVDTHCR), 2028 patients were found to have the acute STEMI. We compared the patients’ characteristics in 109 (5.4%) subjects ≤40 and 1919 subjects > 40 years old. Results: The young patients had less diabetes, hypertension, dyslipidemia and history of MI or prior revascularization, and were more likely to be male (92.7% vs. 74%), smoker (58.7% vs. 31.7%) and have family history of CVD (50.5% vs. 23.4%). The young patients had higher prevalence of angiographically normal coronary artery (13.7% vs. 0.9%; p<0.001). The young patients were more likely to undergo percutaneous coronary intervention (38.5% vs. 18.6%), whereas coronary artery bypass grafting was more common in the old ones (p<0.001). In-hospital death was markedly different among young and old patients (0.9% and 6.1%, respectively; p<0.01). Conclusion: In STEMI population, the risk profile, clinical findings and severity of coronary disease of the young differ substantially from the elderly counterparts. Young patients with STEMI have a favorable outcome compared with that in older patients

Use of brief culture on Lowenstein–Jensen media as pre-polymerase chain reaction (Pre-PCR) to detect Mycobacterium

Background and aim: Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis (TB), does not retain any bacteriological stain due to the high lipid content in its wall. Classic methods like acid-fast staining or Ziehl–Neelsen staining are used for the diagnosis. Nucleic acid amplification techniques, such as polymerase chain reaction (PCR), are very useful in the rapid diagnosis of infections by MTB, but the sensitivity of PCR is considerably lower because of the presence of inhibitory substances in tissues. The aim of this study is to improve the sensitivity of PCR in inhibiting tissue samples. Method and material: Thirty-six lymph nodes isolated from inoculated guinea pigs with BCG vaccine were used. After grinding and suspending samples in sterile distilled water, they were cultured on Lowenstein–Jensen media. DNA extraction was done after 5 days by cetyltrimethylammonium bromide (CTAB) method. Finally, PCR was done for each extracted DNA. Result: This study began with 40 guinea pigs; 4 died before the fourth week. Thirty-six lymph nodes were sent to PRIC lab; all 36 samples were positive in culture and ZN stain. All specimens were assessed by two methods: PCR before and after 5 days of culture. 27.8% (10 samples) and 69.4% (25 samples) were positive PCR before and after brief-culture, respectively. Conclusion: In summary, the aim of this study was to demonstrate the importance of optimal DNA extraction and brief-culture for elevating the efficacy and accuracy of PCR for the rapid detection of lymph node TB

The relationship between neonatal factors and involving with glucose-6-phosphate dehydrogenase deficiency (G6PD) and patients\' outcome in Fars Province

Introduction: Glucose-6-phosphate dehydrogenase deficiency (G6PD) or fauvism is the most common enzyme deficiency in human, so that 400 million people are living with this disease worldwide. This study aimed to investigate the role of some neonatal factors among newborns suffering from G6PD deficiency and neonatal outcomes associated with this disease. Materials and methods: In this study, two methods including case-control and retrospective cohort regarding some neonatal factors associated with G6PD deficiency were used. These methods were performed on 142 children with this kind of deficiency and 142 healthy infants in the city of Marvdasht during 2013- 2014. The analysis of data was based on chi-square tests, t-test, logistic regression, descriptive statistics and estimation of odds ratios or relative risks via SPSS16 software. Results: Totally 284 newborns including 132 (46.6%)/ 152 (53.4%) boys/girls and mean weight on birth of 3163 ± 471 (gr) were analyzed. Comparison of case and control samples did not show any significant differences between sex and involving with G6PD deficiency but the chance of having a baby with this defect in pregnancy intervals between 6 to 8 years was increased (95% CI: 1- 4.4, OR: 2). Relative risk of jaundice in infected and healthy infants was estimated as 3.73, which demonstrated a statistically significant association (95% CI: 1.33- 10.4). The frequency of low birth weight, birth order and type of delivery was associated with the disease, but their differences were insignificant compared to the healthy group. Conclusion: The results of this study showed that the number of hospitalization is increased due to jaundice in infants with G6PD. There is also an insignificant relation between low birth weight, rank of birth and type of delivery. Thus, it is recommended that other consequences of this deficiency need to be revealed by screening other populations with more samples

Impact of Isolated Coronary Artery Bypass Grafting on Non-Organic Tricuspid Regurgitation Severity

Background: Moderate non-organic tricuspid regurgitation (TR) concomitant with coronary artery disease is not uncommon. Whether or not TR improves after pure coronary artery bypass grafting (CABG), however, is unclear. The aim of this study was to evaluate the effect of isolated CABG on moderate non-organic TR.Methods: This study recruited 50 patients (40% female, mean age: 65.38±8.01 years, mean left ventricular ejection fraction (LVEF): 45.74±13.05%) with moderate non-organic TR who underwent isolated CABG. TR severity before and after CABG was compared. Pulmonary arterial systolic pressure (PAPs)>30mmHg and LVEF<50% were considered elevated PAPs (EPAPs) and LV systolic dysfunction, respectively. Presence of Q-wave in leads II, III, and aVF was considered inferior myocardial infarction (inf. MI).Results: Pre-operatively, 81.5% of the patients had EPAPs, 16% right ventricle (RV) dilation, and 50% left ventricle (LV) and 16% RV systolic dysfunction. TR severity improved in 64% after CABG, whereas it remained unchanged or even worsened in others (P value<0.001). Patients with inf. MI showed no improvement in TR, while patients without inf. MI had significant TR regression after CABG (P value=0.050). Improvement of TR severity after CABG was not related to pre-operative RV size and function, LV systolic function, or PAPs reduction.Conclusion: Although TR severity decreased remarkably after isolated CABG, a considerable number of the patients had no TR regression. In addition, only absence of inf. MI was significantly correlated to TR improvement after CABG. Further prospective studies with long-term follow-up are needed to determine the other factors predicting TR regression after isolated CABG