THE CALCULATION OF THE PIPE DIAMETER AND CHANGE WITH TEMPERATURE OF VAPOUR COMPRESSION REFRIGERATION SYSTEM USING VARIOUS ALTERNATIVE REFRIGERANTS

Bu çalışmada, yeni nesil soğutucu akışkanların kullanıldığı soğutma sistemlerinin emme ve basma hatlarında yağlama yağının sürüklenebilmesi için gerekli boru çapı hesaplanarak sıcaklığa göre değişimi incelenmiştir. Çalışmanın ilk aşamasında belirlenen tahmini boru çaplarına göre emme ve basma hattında bulunan borulardaki yağın sürüklenebilmesi için gerekli olan minimum soğutucu akışkan hızı (Vr,min) ve minimum soğutma yükü (qr,min) değerleri hesaplanmış, bu hesaplanan değerler ışığında kullanılması gereken gerçek boru çapları hesaplanmıştır. Analizler, soğutma yükünün 1 kW olduğu bir soğutma sisteminde K ve L tipi bakır borular için ozon tabakasına zarar veren ve küresel ısınmaya yol açan soğutucu akışkanların yerine çevre dostu alternatif akışkanlardan R134A, R410A ve R423A soğutucu akışkanları kullanılmıştır

Boru Çapının Soğutucu Akışkan Hızına ve Soğutma Yüküne Etkisi

The aım of this study is the calculation of the pipe diameter required to transfer the oil in the vertical parts of the cooling systems, at the desired cooling load and at the velocity of the minimum cooling liquid. For this purpose, the velocity of the minimum cooling liquid for the driftage of the oil in the pipes in the suction line (Vs,min) and the minimum cooling load (qs,min) have been studied. After the theoretical analysis as to the matter, in a system the cooling load of which 1 kW, for the copper pipes whose types are K and L, in place of the cooling liquids harming the ozon layer and leading to global warming, the environment-friendly, natural and alternative liquids R134A, R410A, R423A and R744 have been used. According to the results, as the pipe diameters increase, the velocity of minimum cooling liquid for the driftage of the oil increases. In addition to that, the load of the minimum cooling liquid increases, both the pipe diameters and the heat of the evaporator being increased. Cooling liquids being considered, the change of the velocities as R744<R410A<R423A<R134 have been obtained. The change in the minimum cooling load as R423A<R134A<R410A<R744 have been obtained.1. Giri

Diagnostic Value of Cyclophilin A in Acute Ischemic Stroke

Aim: The early diagnosis and treatment of patients presenting to the emergency department symptoms of stroke can significantly reduce mortality and morbidity rates associated with it. This study aimed to investigate the diagnostic value of serum yclophilin A levels in our study group who presented to the emergency department with symptoms of acute ischemic stroke.Materials and Methods: In total, 114 patients diagnosed with acute ischemic stroke between October 2013 and October 2014 and a control group of 66 healthy volunteers were included. Cyclophilin A levels in the patient and control groups were compared. Results: The median cyclophilin A levels in the patient and control groups measured at the time of presentation were 13.47 (11.97-17.92) ng/mL and 11.54 (8.48-16.22) ng/mL, respectively. These levels were significantly higher in the patient group than in the control group (p<0.05). Conclusion: Plasma cyclophilin A levels were significantly higher in the patient group than in the control grou

Diagnostic Value of Procalcitonin Levels in Acute Mesenteric Ischemia

Background: Acute mesenteric ischemia (AMI) is a potentially fatal disease. Difficulties in diagnosis make it essential to find early biomarkers. Aims: This study investigated the diagnostic value of procalcitonin (PCT) levels in AMI. Study Design: Animal experimentation. Methods: Rats were divided into six groups of six animals each. In the experimental group, an experimental ischemia model was established by clamping the superior mesenteric artery from the aortic outflow tract. Blood and tissue specimens were collected from rats in the experimental mesenteric ischemia model at 30 min and 2 and 6 h, and these were compared with specimens from the respective control groups. PCT levels were compared at 30 min and 2 and 6 h. Results: PCT levels were 185.3 pg/mL in the control group and 219.3 pg/mL in the study group, 199.6 pg/mL in the control group and 243.9 pg/mL in the study group, and 201.9 pg/mL in the control group and 286.9 pg/mL in the study group, respectively, at 30 minute, 2 and 6 hours. Significant differences were determined between 6-h control group and ischemia group PCT levels (p=0.005). Conclusion: The absence of a significant increase in PCT levels in the early period, while a significant difference was detected in the later period (6 h), shows that PCT levels rise late in mesenteric ischemia and can be a marker in the late period

Usefulness of admission matrix metalloproteinase 9 as a predictor of early mortality after cardiopulmonary resuscitation in cardiac arrest patients

YILMAZ, MEHMET BIRHAN B/0000-0002-8169-8628; YILMAZ, Mehmet Birhan/0000-0002-8169-8628; YILMAZ, MEHMET BIRHAN/0000-0002-8169-8628; kukul guven, fatma mutlu/0000-0003-3755-6021WOS: 000311997600021PubMed: 22633700Background: Matrix metalloproteinases (MMPs) have a central role in disease progression after ischemia-reperfusion injury. However, its prognostic significance in cardiac arrest (CA) patients having cardiopulmonary resuscitation (CPR) is unknown. The aim of this study was to investigate the relation between admission MMP-9 level and early mortality in CA patients. Methods: A total of 96 in-hospital or out-of-hospital CA patients and 40 age-and sex-matched healthy volunteers as the control group were evaluated prospectively. The patients were classified according to the CPR response into a successful group (n = 46) and a failed group (n = 50). Results: The MMP-9 levels were detected to be 56.9 +/- 4.3, 69.5 +/- 7.4, and 92.7 +/- 10.1 ng/mL in the control group, the successful CPR group (acute responders), and the failed CPR group, respectively (P < .001 for the 2 comparisons). The MMP-9 level on admission, presence of asystole, mean CA duration, out-of-hospital CPR, sodium and potassium levels, and arterial pH were found to have prognostic significance in univariate analysis. In addition, MMP-9 levels were correlated with age, troponin level, and oxygen saturation. In multivariate logistic regression analysis with forward stepwise method, only MMP-9 level on admission (odds ratio, 1.504; P < .001) and mean CA duration before CPR (odds ratio, 1.257; P = .019) remained associated with post-CPR early mortality after adjustment of other potential confounders. In addition, optimal cutoff value of MMP-9 to predict failed CPR was found as greater than 82 ng/mL, with 88% sensitivity and 97.8% specificity. Conclusions: High MMP-9 levels were associated with worse clinical and laboratory parameters, and it seems that MMP-9 helps risk stratification in CA patients. (C) 2012 Elsevier Inc. All rights reserved

Usefulness of admission matrix metalloproteinase 9 as a predictor of early mortality after cardiopulmonary resuscitation in cardiac arrest patients

YILMAZ, MEHMET BIRHAN B/0000-0002-8169-8628; YILMAZ, Mehmet Birhan/0000-0002-8169-8628; YILMAZ, MEHMET BIRHAN/0000-0002-8169-8628; kukul guven, fatma mutlu/0000-0003-3755-6021WOS: 000311997600021PubMed: 22633700Background: Matrix metalloproteinases (MMPs) have a central role in disease progression after ischemia-reperfusion injury. However, its prognostic significance in cardiac arrest (CA) patients having cardiopulmonary resuscitation (CPR) is unknown. The aim of this study was to investigate the relation between admission MMP-9 level and early mortality in CA patients. Methods: A total of 96 in-hospital or out-of-hospital CA patients and 40 age-and sex-matched healthy volunteers as the control group were evaluated prospectively. The patients were classified according to the CPR response into a successful group (n = 46) and a failed group (n = 50). Results: The MMP-9 levels were detected to be 56.9 +/- 4.3, 69.5 +/- 7.4, and 92.7 +/- 10.1 ng/mL in the control group, the successful CPR group (acute responders), and the failed CPR group, respectively (P < .001 for the 2 comparisons). The MMP-9 level on admission, presence of asystole, mean CA duration, out-of-hospital CPR, sodium and potassium levels, and arterial pH were found to have prognostic significance in univariate analysis. In addition, MMP-9 levels were correlated with age, troponin level, and oxygen saturation. In multivariate logistic regression analysis with forward stepwise method, only MMP-9 level on admission (odds ratio, 1.504; P < .001) and mean CA duration before CPR (odds ratio, 1.257; P = .019) remained associated with post-CPR early mortality after adjustment of other potential confounders. In addition, optimal cutoff value of MMP-9 to predict failed CPR was found as greater than 82 ng/mL, with 88% sensitivity and 97.8% specificity. Conclusions: High MMP-9 levels were associated with worse clinical and laboratory parameters, and it seems that MMP-9 helps risk stratification in CA patients. (C) 2012 Elsevier Inc. All rights reserved

A study to develop clinical decision rules for the use of radiography in wrist trauma: Karadeniz wrist rules

Tatli, Ozgur/0000-0003-0263-7630; BAYDIN, AHMET/0000-0003-4987-0878; Turedi, Suleyman/0000-0002-6500-3961WOS: 000389517200004PubMed: 27450389Introduction: the aim of this study was to evaluate patients presenting to the emergency department (ED) with wrist trauma using physical examination findings and functional tests and to identify findings with high sensitivity and specificity among the parameters assessed in patients with fracture in the wrist. the ultimate objective was thus to establish a reliable and widely usable clinical decision rule for determining the necessity of radiography in wrist trauma. Methods: This prospective, multicenter study was performed in 8 hospitals. the relation between radiologically determined fracture and clinical findings consisting of physical examination findings and functional tests was assessed in terms of whether or not these were markers of radiography requirement, with the aim of identifying predictive values for fracture. Results: A total of 603 eligible trauma patients presented to the participating EDs during the study period. Fracture was identified in 24.5% of patients (n= 148). the 4-way combination with the highest sensitivity was identified as axial compression and the positive distal radioulnar drawer test, and pain with radial deviation and dorsal flexion. Sensitivity at distal ulna palpation was added as a fifth parameter, and sensitivity and negative predictive value thus increased to 100%. Conclusion: With their 100% sensitivity and 100% negative predictive values, the Karadeniz wrist rules may represent a clinical decision rule that can be used in practice in EDs. If all 5 findings are negative, there is no indication for wrist radiography. (C) 2016 Elsevier Inc. All rights reserved