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    Exergy, exergoeconomic, and sustainability analyses of a diesel engine using biodiesel fuel blends containing nanoparticles
    (Pergamon-Elsevier Science Ltd, 2023) Dogan, Battal; Celik, Mehmet; Bayindirli, Cihan; Erol, Dervis
    The current paper investigated in detail the influence of titanium dioxide (TiO2) and silver oxide (Ag2O) nanoparticles additives into biodiesel fuel obtained from cottonseed oil in terms of performance and emissions. The fuel blends formed by nanoparticles with biodiesel fuel were evaluated from a different perspective with energy, exergy, and exergoeconomic analyses by utilizing the data from the experiments. Thermal efficiency and exergy efficiency increase when nanoparticles were mixed to the biodiesel fuel. Total exergy losses in fuel blends decrease with the nanoparticle additives. When the engine torque was 40 Nm, the total exergy losses for C100, CAg-75, and CTi-75 test fuels were 14.49 kW, 13.91 kW, and 12.17 kW, respectively. The total exergy loss in D100 fuel was calculated as 12.04 kW under the same conditions. The sustainability indexes for D100 and CTi-75 fuels at an engine torque of 40 Nm were 1.626 and 1.620, respectively. Due to the high price of nanoparticles, test fuels with nanoparticles have a higher cost per unit exergy for engine work than pure biodiesel fuel. Hence, it is essential to decrease the cost of nanoparticle production to expand the using of nanoparticle additives in biodiesel.
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    Predictive Significance of Laboratory Tests in Bacteremic Brucellosis
    (Iranian Scientific Society Medical Entomology, 2024) Celik, Mehmet; Cicek, Yeliz; Atalay, Ebru; Altindag, Deniz; Akgul, Fethiye; Urkmez, Fatma Yekta; Gurbuez, Esra
    Background: Brucellosis is one of the most common zoonotic infections. Although culture is the gold standard diagnostic method, bacterial growth in blood cultures may not always occur due to various factors. We aimed to investigate demographic, clinical, and laboratory findings that may have predictive significance for bacteremia in brucellosis. Methods: Patients older than 18 years of age followed up with a diagnosis of brucellosis between 2012 and 2022 were included in this retrospective multicenter study. They were divided into two main subgroups according to their Brucella species reproductive status as bacteremic and non-bacteremic. Results: A total of 743 patients, 370 (49.80%) bacteremic and 373 (50.20%) non-bacteremic brucellosis patients, were enrolled. The mean age of the bacteremic group (36.74 years) was lower than the non-bacteremic group (43.18 yr). High fever, chills/cold, sweating, nausea, vomiting, and weight loss were more common in the bacteremic group. In the bacteremic group, white blood cell count, platelet count, hemoglobin level, mean platelet volume, eosinophil, and neutrophil counts were lower, and lymphocyte, erythrocyte sedimentation rate, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and ferritin levels were higher. According to the receiver operating characteristic (ROC) analysis, when the cut-off value of ferritin was considered 67, it was the parameter with the strongest predictive significance in Brucella bacteremia. Conclusion: High ferritin level, low eosinophil count, and increased erythrocyte sedimentation rate were determined as the most critical laboratory findings in predicting bacteremia in brucellosis.