A comparison of dexmedetomidine, moxonidine and alpha-methyldopa effects on acute, lethal cocaine toxicity

Background: The treatment of cocaine toxicity is an important subject for emergency physicians. We investigated the effects of dexmedetomidine, moxonidine and alpha-methyldopa on acute cocaine toxicity in mice. Objectives: The aim of this study was to evaluate the effects of dexmedetomidine, moxonidine and alpha-methyldopa in a mouse model of acute cocaine toxicity. Materials and Methods: We performed an experiment consisting of four groups (n = 25 each). The first group received normal saline solution, the second group received 40 μg/kg of dexmedetomidine, the third group received 0.1 mg/kg of moxonidine and the fourth group received 200 mg/kg of alpha-methyldopa, all of which were intraperitoneally administered 10 minutes before cocaine hydrochloride (105 mg/kg). All animals were observed for seizures (popcorn jumping, tonic-clonic activity, or a loss of the righting reflex) and lethality over the 30 minutes following cocaine treatment. Results: The ratio of animals with convulsions was lower in all treated groups when compared to the control (P 0.05). In addition, the time to lethality was also longer in the same group (P < 0.001). Conclusions: The present study provides the first experimental evidence in support of dexmedetomidine treatment for cocaine-induced seizures. Premedication with dexmedetomidine reduces seizure activity in a mouse model of acute cocaine toxicity. In addition, while dexmedetomidine may be effective, moxonidine and alpha-methyldopa did not effectively prevent cocaine-induced lethality. © 2015, Iranian Red Crescent Medical Journal

Kruvaziyer ve Ro-Ro gemilerinde organik Rankine çevrimi sistemi kullanımının liman sahaları üzerindeki çevresel etkileri

Bu çalışma ile gemilerin liman sahası çevresinde ürettiği salımların azaltılması hedeflenmektedir. Çalışmada, Çeşme Limanına 2017 yılı içerisinde sefer yapan bir yolcu gemisi ile bir RO-RO gemisinin seferleri incelenmektedir. Geminin liman sahasına girdiği koşul, manevra saatinin başladığı koşul olarak kabul edilmiştir. Buna göre, bu gemilerin ayrılma ve yanaşma sırasında manevra süresi ile limanda kaldığı süre hesaba katılarak, teorik yöntemler ile liman sahasında oluşan CO2 gazı salım miktarları ortaya konmuştur. Bunun yanında, bu gemilerde ORC sistemlerinin kurulması ile elde edilebilecek kazançlar ayrıca incelenmektedir

Item analyses of Turkish Society of Cardiovascular Surgery Board 2015 written exam

WOS: 000357842000002Background: This study aims to analyze the items of the recent board written exam conducted by the Turkish Society of Cardiovascular Surgery and develop recommendations on key issues to prepare a superior exam set for future exams. Methods: In the study, items of the recent board exam, which was held in Eskisehir on April 12, 2015, were analyzed in terms of difficulty, discrimination, and validity. Results: It was detected that correct answer items were distributed equally in the exam set, the average rate of questions answered correctly was 63.79%, 59% of the questions were answered correctly above average, and range of exam scores was wide. Rate of questions with desired difficulty index level was 51% and rate of questions with desired discrimination index level was 76%. Of the questions, 9% was invalid while 66% had a high level of validity. Conclusion: Board written exam seems to be a valid test since exam questions cover all topics in the field of expertise, and the number of questions and rate of valid questions are high. The proportion of those successful in the exam was high and candidates were entitled to take the next step. It is assumed that candidates will be successful in the next phase

Operation-dependent exergetic sustainability assessment and environmental analysis on a large tanker ship utilizing Organic Rankine cycle system

This study focuses on the novel perspective of marine ORC systems with a detailed marine diesel generator plant simulation integrated with an ORC system model to evaluate environmental impacts and energy efficiency increments by reducing the number or the load of generators by using the ORC system support during operation. It is aimed to analyze the fuel-saving potential and sustainability performance of the power generation plant of a tanker ship when an ORC is integrated. The thermodynamic system simulation determined the fuel consumption of the plant within two years regarding six operation modes. The results show that the optimum working fluid is R1336mzz (Z) for the evaporation pressure of 16 bar. Organic Rankine cycle system integration provided a total fuel-saving of 15% from diesel generators and the total fuel consumption of the vessel was reduced by 5.16%. The sustainability performance of the system was ensured with a novel operation-dependent approach that enhances the exergetic sustainability assessment by considering the operation modes of the vessel and the time spent on these operations for a certain time. The load reduction in the generators resulted in better sustainability performance and the operation-dependent indicators were affected by operations having more working hours

Environmental and economic analyses of fuel cell and battery-based hybrid systems utilized as auxiliary power units on a chemical tanker vessel

This study aims to investigate the environmental and economic impacts of implementing fuel cell and battery-based hybrid configurations. Phosphoric acid and molten carbonate fuel cell systems in the place of diesel generators of a large tanker to supply the vessel's total electricity demand. Environmental and economic analyses of the utilization of the specified fuel cell systems with LiNiCoALO2 and LiNiMnCoO2 chemical types of battery cells on a large marine vessel are provided in this paper. In addition, the assessment of the most suitable battery cell and charge-discharge hours for fuel cell systems is carried out with a grid-search algorithm. Six different fuel cell and battery configurations are investigated to obtain the optimum system layout. The results show that the CO2 emissions could be reduced by up to 49.75% and the lowest electricity production cost is found as 0.181 $/kWh for the current fuel prices with the utilization of molten carbonate fuel cells and LiNiMnCoO2 battery cells

Thermal design and analysis of an organic rankine cycle system utilizing the main engine and cargo oil pump turbine based waste heats in a large tanker ship

The utilization of main engine-based waste heat sources using organic Rankine cycle (ORC) systems is only available during the navigation phases of marine vessels, which leads to reductions in the system uptake time and economic viability of the investment during cargo loading/discharging operations and waiting periods in ports. The novel perspective of this study is to propose the cargo oil pump turbine (COPT) based waste heat as a utilizable source, which has not been introduced in the literature yet, and show the economic viability of ORC systems for tanker ships. In this regard, a new waste heat recovery system specifically designed for a reference crude oil tanker ship was introduced that can utilize both main engine-based waste heat during navigation and COPT-based waste heat during cargo discharge operations. The optimal heat exchanger network of the main engine and COPT-based waste heats was designed using pinch point analysis method for achieving optimum waste heat recovery. Energy and exergy analyses were conducted for the proposed ORC integrated waste heat recovery system for both navigation and discharge operation modes of the ship. The economic performance of the ORC system was further assessed by calculating payback periods and levelized energy costs for eleven design points. The highest energy conversion efficiency (16.2%) was achieved when the ORC condenser outlet temperature was taken as 15 °C for R1233zd(E). COPT based waste heat reduced the levelized energy cost of the system by at least 8.9% and the minimum levelized energy cost value was obtained as 0.1307. The best economic performance was yielded with COPT utilization at design point 9 with a payback period of 6.2 years, which was reduced by at least 0.7 years with the utilization of COPT based waste heat.</p

Operation-dependent exergetic sustainability assessment and environmental analysis on a large tanker ship utilizing Organic Rankine cycle system

This study focuses on the novel perspective of marine ORC systems with a detailed marine diesel generator plant simulation integrated with an ORC system model to evaluate environmental impacts and energy efficiency increments by reducing the number or the load of generators by using the ORC system support during operation. It is aimed to analyze the fuel-saving potential and sustainability performance of the power generation plant of a tanker ship when an ORC is integrated. The thermodynamic system simulation determined the fuel consumption of the plant within two years regarding six operation modes. The results show that the optimum working fluid is R1336mzz (Z) for the evaporation pressure of 16 bar. Organic Rankine cycle system integration provided a total fuel-saving of 15% from diesel generators and the total fuel consumption of the vessel was reduced by 5.16%. The sustainability performance of the system was ensured with a novel operation-dependent approach that enhances the exergetic sustainability assessment by considering the operation modes of the vessel and the time spent on these operations for a certain time. The load reduction in the generators resulted in better sustainability performance and the operation-dependent indicators were affected by operations having more working hours.</p

The role of inducible nitric oxide synthase in urinary bladders of cattle with enzootic hematuria and its struggle with uroplakin III

Changes in uroplakin secretion in the urothelium leads a gradual ability lost in neoplastic conditions. Urothelium is one of the target regions where nitric oxide can damage. Therefore, in this study, the presence of iNOS and UPIII were investigated in bovine enzootic hematuria cases. The results were supported by comparing them with those achieved by critical markers for malignancy of tumor such as caspase 3, Bax, p53, PCNA, and VEGF. The presence of 8-OHDG, a good marker for oxidative DNA damage, was also investigated. For this purpose, urinary bladders with enzootic hematuria were collected from the slaughterhouses. In histopathological examinations, neoplastic, pre-neoplastic, and inflammatory lesions were observed in these urinary bladders. In immunohistochemical examinations, iNOS reacts as negative in the UPIII positive healthy urothelium which preserves the structure of AUM. On the other hand positive reaction has been observed in AUM modified and UPIII negative urothelium. In these cases, as an indicator of oxidative damage, 8-OHdG positivity was observed in the UPIII negative and iNOS positive areas. Additionally, increased cell proliferation, decreased apoptosis as well as p53 disorganization were clearly observed in most of the cases. Thus, the active role of nitric oxide, as a free radical derivative, has been shown in the enzootic hematuria cases of cattle

Comparison of various metaheuristic algorithms to extract the optimal PEMFC modeling parameters

In this study, operating parameters of a semi-empirical mathematical model of a proton-exchange membrane fuel cell (PEMFC) are extracted and compared using various metaheuristic algorithms to analyze its behavior in a fast and economical manner before setting it up for application. Sum-squared error is employed as the objective function to find the values of seven unknown modeling parameters. The parameter extraction is carried out by using the&nbsp;polarization curve&nbsp;data of a 1000&nbsp;W commercial PEMFC. Three different multi-attribute decision-making methods are used to rank the metaheuristic algorithms in terms of performance. The findings indicate that Moth Flame Algorithm is ranked first considering the sum-squared error (0.4389) and runtime (1054&nbsp;s); whereas Grey Wolf Optimizer gives the best objective function efficiency (98.6034%) and lowest error rate (0.1096). It was also found that JAYA and Cuckoo Search are not convenient for parameter extraction of the specified fuel cell. Overall, the distinctive features of the study provide valuable insights and advancements in the field of&nbsp;fuel cell modeling&nbsp;and optimization.</p