Fuzzy Decision Mechanism for Stock Market Trading

Investors utilize various methods to make buy/sell decisions depending on time-dependent stock market prices. In this study, a fuzzy decision mechanism that makes buy/sell decisions for stock market data is proposed. The proposed mechanism generates instant buy/sell decisions by evaluating three popular indicators which are the Moving Average Convergence/Divergence (MACD) Strategy, Chaikin Money Flow (CMF), and Stochastic Oscillator (SO). The fuzzy decision mechanism has three inputs and one output which are defined by using Gaussian membership functions. In the design of the decision mechanism, Mamdani inference method is used and the rule table is defined by nine rules. Therefore, the structure of the proposed fuzzy decision mechanism is simple and straightforward. The performance of the proposed fuzzy decision mechanism is compared with two classical decision mechanisms using MACD and CMF indicators separately. In the comparisons, the stock market data of Borsa Istanbul 100 Index (XU100), Dow Jones Industrial Average (^DJI), and S&P 500 (^GSPC) are used. The comparison results show that the proposed fuzzy decision mechanism provides significantly higher profit than the mechanisms using either MACD or CMF indicators for all stock market data.115988

Is there a difference between normotensive and hypertensive patients in terms of blood parameters and cardiovascular diseases?

Objectives: It has been stated in various studies that there is a difference in some blood parameters between hypertensive and normotensive patients for a long time. Mean platelet volume (MPV), and red blood cell distribution width (RDW), have been studied in hypertensive patient groups in many studies. Hypertension is a classic risk factor for ischemic stroke and myocardial ischemia, as known. In our study, we examined whether there was a difference between hypertensive patient groups and normotensive patients in terms of blood parameters such as MPV and RDW, and the incidence of stroke and myocardial infarction.Methods: Blood samples and twenty-four-hour ambulatory blood pressure monitoring (ABPM) results of 552 patients admitted to our outpatient clinic with a pre-diagnosis of hypertension were retrospectively analyzed. According to ABPM results, we divided the study participants into four groups; dippers, non-dippers, extreme dippers, and normotansives. Complete blood count and biochemical test results were found in the database of our hospital for all patients and differences between groups were investigated.Results: One hundred seventy three normotensives (Group 1) (mean age, 47.4 ± 15.4 years), 210 non-dippers (Group 2) (mean age, 53.8 ± 15.8 years), 67 extreme dippers (Group 3) (mean age, 49.1 ± 15.9 years) and 102 dippers (Group 4) (mean age, 52.2 ± 12.5 years). Daytime mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) and night-time mean SBP and DBP were significantly different in groups (Group 1: 117 [90-193] mmHg and 71 [55-87] mmHg; Group 2: 137 [107-188] mmHg and 83 [107-188] mmHg; Group 3: 143 [115-193] mmHg and 88 [56-122] mmHg; and Group 4: 140.5 [116-173] mmHg and 76 [55-124] mmHg), p < 0.001; respectively. MPV and RDW levels were different in all four groups (p < 0.001). We found a significant difference in the rates of stroke and coronary artery disease between the four groups (p = 0.018 and p = 0.002, respectively). In the ROC curve analysis MPV had sensitivity of %77. 8 and specificity of 78. 1% for stroke when the cut-off value MPV was 9.25 (Area under curve: 0.808, 95% confidence interval: 0.726-0.889, p < 0.001).Conclusions: In our study, MPV and RDW levels and the rates of stroke and cardiovascular disease were significantly higher in non-dipper patients compared to other groups

Endarterectomy and saphenous vein ‘Y’ patchplasty technique for severe carotid artery bifurcation lesion

Arteriosclerosis, is mostly affect coronary and carotid arteriesespecially the ostium and bifurcation due to the natureof the flow. Arterial bifurcation lesions cause dilemmafor the treating physician during both surgical and invasiveprocedures because they require a higher clinical experienceand longer processing time. In carotid artery surgery,it is accepted that patchplasty prevents perioperativeand postoperative restenosis, and as a result of this, itreduces the incidence of ipsilateral stroke. In the presenttime synthetic patch materials (PTFE, Dacron) and autologouspatch materials (saphenous and jugular veins) areused. We report a case of carotid endarterectomy and ‘Y’shaped saphenous patchplasty to the carotid bifurcation.According to our research in the literature, we didn’t findany case with ‘Y’ shaped saphenous vein patch. Therewas only one Y shaped carotid patchplasty case by usingPTFE material. Our original technic is advantageous interms of easy preparation and application as well as itssuccessful outcome.Key words: Carotid artery diseases, saphenous vein,patchplast

Giant size abdominal aortic aneurysm repair using open proximal anastomosis under hypothermic circulatory arrest: A report of two cases

Hypothermic total circulatory arrest and open proximal anastomosis techniques are not commonly used in abdominal or juxtarenal abdominal aortic aneurysm repair. Proximal aortic clamping is usually adequate for surgical repair of abdominal aortic pathologies. We present two cases of giant-sized abdominal aortic aneurysms, one was juxtarenal and one was a Crawford type IV thoracoabdominal aneurysm, that were repaired by using open proximal anastomosis under hypothermic total circulatory arrest and a transabdominal approach. This technique may be useful for both thoracoabdominal and large abdominal aortic aneurysms because it offers the opportunity to not clamp the aorta and operate in bloodless surgical field

Comparison of Patency of the Saphenous Vein and Left Internal Mammary Artery in Left Descending Coronary Artery Bypass Graft Position

Amaç: Bizim bu çalışmadaki amacımız, koroner bypas operasyonlarında (CABG), sol anteriyor desenden koroner arterin (LAD) revaskülarizasyonunda kullanılan sol internal mamarial arter (LİMA) ile safen ven greftinin (SVG)klinik sonuçlarını ve uzun dönem açıklık oranının değerlendirilmesidir. İlave olarak safen ven greftinin diğer koroner arter pozisyonlarında ki açıklık oranını da değerlendirildi. Metot: Ocak 2012-Kasım 2014 arasında hastanemizde, daha önce koroner bypass cerrahisi geçirmiş ve iskemik semptomları olan 178 hastaya koroner angiografi yapıldı. Bu hastaların preoperatif ve postoperatif bilgilerini değerlendirildi. Hastalar LAD ye yapılan anastomozuna göre LİMA grubu ve SVG grubu olarak ikiye ayırıldı. Greftte, oklüzyon, string sign veya %80 den daha fazla darlık varsa greft yetmezliği olarak tanımlandı. Diğer koroner arterleri de subgrup analizi olarak değerlendirildi.Sonuç: Her iki grup arasında preoperatif olarak komorbidite, yaş ve acil operasyona alma açısından önemli bir fark yoktu. Hastaların ortalama takip zamanı SVG grubunda 48 ay, LİMA grubun da 60 ay oldu. LİMA greftlerinin oklüzyon oranı, SVG grubundan daha düşüktü ( (%9.9%vs. %22.2 p=0.001). subgrup analizlerinde SVG in patensi, en düşük olarak diyagonal koroner arterde bulundu(%46.9, p=0.005).Tartışma: Venöz veya arteriel konduitin seçimi, hem greft patensi için, hem de semptomsuz periyodun elde edilmesinde sol koroner desenden arter için önemlidir. Ayrıca safen ven grefti diagonal artere anastomoz edildiği zaman en düşük açıklık oranına sahiptir.Objective: We aimed to evaluate long-term patency rates and clinical outcomes of the saphenous vein (SVG) and left internal mammary artery (LIMA) in left anterior descending coronary artery (LAD) position to investigate the optimum conduit for coronary artery bypass graft (CABG) operations. In addition we investigated the SVG patency in the other coronary artery positions. Methods: From January 2012 to November 2014, there were 178 patients who were previously undergone coronary artery bypass surgery and had ischemic symptoms, were restudied with coronary angiography in our hospital. We evaluated the preoperative and postoperative data of those patients. The patients were divided into two groups according to the graft anastamosed to LAD; LIMA group and SVG group. Grafts are defined as failed if there was occlusion, string sign, or greater than 80% stenosis. We analyzed also other coronary artery targets by subgroup analysis.Results: There were no significant differences between each group in preoperative comorbidity, age, or urgency. The mean follow-up time of the patients were 48 months in SVG group and 60 months in LIMA group. Occlusion rates of the LIMA grafts were lower than SVG (9.9% vs. 22.2% p=0.001). Subgroup analysis revealed that, as a target vessel diagonal coronary artery has the lowest SVG patency rates (46.9%, p=0.005).Conclusion: Selection of arterial or venous conduit for the left descending coronary artery has significantly affected both patency rate and symptom-free period. In addition, saphenous vein grafts has the lowest patency rates when anastamosed to the diagonal artery