Zonguldak Karaelmas University

About: Zonguldak Karaelmas University is a based out in . It is known for research contribution in the topics: Population & Copolymer. The organization has 1939 authors who have published 4296 publications receiving 62466 citations.

Energy–exergy–ANN analyses of solar-assisted fluidized bed dryer

Abstract: In this study, a temperature-controlled solar air collector was designed and tested for drying. Solar drying systems have two disadvantages. First one is the lack of ability to store energy and the...

A parametric kind of the Fubini-type polynomials

Abstract: By introducing two specific generating functions, we define a kind of parametric Fubini-type polynomials. We investigate some fundamental properties of these parametric-kind Fubini-type polynomials. In particular, we derive the relations between the parametric-kind Fubini-type polynomials and other polynomials including (for example) the parametric-kind Apostol–Bernoulli, the Apostol–Euler and the Apostol–Genocchi polynomials of order $$\alpha $$. Finally, we derive several families of multilinear and multilateral generating functions for the parametric-kind Fubini-type polynomials as well as other polynomials which are considered in this paper.

Long‐time variations of precipitable water vapour estimated from GPS, MODIS and radiosonde observations in Turkey

Abstract: Water vapour and its variations in the Earth's atmosphere are related to atmospheric activities and climate changes. However, it is difficult to obtain high-resolution and high-accuracy precipitable water vapour (PWV) and its variations using traditional techniques, particularly in Turkey with the complex weather variability caused by the proximity of the Black Sea and the Mediterranean Sea. Satellite observations provide unique ways to observe PWV variations at regional or global scale, e.g. global positioning system (GPS). In this study, long-time PWV variations and trends are investigated and obtained from 6-year continuous GPS observations in Turkey (January 2010–January 2016), which are compared with nearly co-located radiosonde and moderate resolution imaging spectroradiometer (MODIS) observations to check its accuracy. The root mean square error (RMSE) of PWV differences is about 1–3 mm between radiosonde and GPS, and 3–7 mm between MODIS and GPS. Furthermore, the linear trend and seasonal amplitudes, and phase of the GPS-estimated PWV signals are computed. Statistically significant trends are found at all stations. While stations near the Mediterranean Sea have increasing trends with about 0.30 mm year−1, the stations at inland have increasing trends of about 0.10 mm year−1. The annual phases between radiosonde, GPS and MODIS PWV at all the stations are almost close to each other with differences in 1°–2°. Finally, the relation between north Atlantic oscillation (NAO) and PWV trends is investigated. Results show that PWV trends agree with NAO behaviours especially for the stations near the Mediterranean Sea. The recent human activities may have impacts on long-term PWV variation trends.

Dexmedetomidine did not reduce the effects of tourniquet-induced ischemia-reperfusion injury during general anesthesia.

Abstract: Ischemia reperfusion injury causes the release of free oxygen radicals Free oxygen radicals initiate the production of toxic metabolites, such as malondialdehyde (MDA), through the lipid peroxidation of cellular membranes Following lipid peroxidation, the antioxidant enzyme system is activated against reactive oxygen species (ROS) and attempts to protect cells from oxidative damage There is a balance between the scavenging capacity of antioxidant enzymes and ROS Because of this balance, the total antioxidant capacity (TAC) measurement is a sensitive indicator of the overall protective effects of the antioxidants Alpha(2) receptor agonists are effective in preventing hemodynamic reactions during extremity surgeries by preventing the release of catecholamines secondary to tourniquet application They have also been shown to possess preventive effects in various ischemia-reperfusion injury models In our study, we examined the effects of dexmedetomidine on tourniquet-induced ischemia-reperfusion injury in lower extremity surgeries performed under general anesthesia The effects of dexmedetomidine were measured with serum MDA and TAC levels We studied 60 adult American Society of Anesthesiologists (ASA) physical status I or II patients undergoing one-sided lower extremity surgery with tourniquet The patients were randomly divided into two groups Group D was administered a dexmedetomidine infusion at a rate of 01μg/kg/minute(-1) for 10 minutes prior to induction and then at 07μg/kg/hour(-1) until 10 minutes before the end of the operation The control group (Group C) received a saline infusion of the same amount and for the same period of time General anesthesia was induced with thiopental, fentanyl, and rocuronium and maintained with nitrous oxide and sevoflurane in both groups Venous blood samples were obtained before the administration of the study drugs (basal) at 1 minute before tourniquet release and at 5 and 20 minutes after tourniquet release (ATR) In both groups, MDA levels decreased at 5 and 20 minutes ATR when compared with the basal values (p<005) TAC levels decreased at 1 and 5 minutes ATR and then returned to basal values at 20 minutes ATR (p<005) In reference to the prevention of lipid peroxidation in tourniquet-induced ischemia-reperfusion injury, the results from the two groups in our study showed that dexmedetomidine did not have an additional protective role during routine general anesthesia