ABSTRACT
It is possible to state that presently the transport area is responsible for a considerable part of the generated greenhouse gases and that transport is one of the main polluters in urban territories. However, at the same time, it is necessary to say that vehicles equipped with internal combustion engines are always the most popular among people thanks to the undoubted advantages of the piston combustion engines. Nowadays, several hundred millions of vehicles with combustion engines within the EU and about 1.5 milliard of such vehicles worldwide are utilized. The only reasonable possibility to reduce gaseous emissions generated by the motor car transport and to keep in operation vehicles equipped with the combustion engines is utilization of new fuels, namely, synthetic fuels. A very favorable idea is the innovative technology, which is called the low-temperature combustion (LTC). The LTC technology offers high efficiency of modern internal combustion engines together with the application of new climate-neutral fuels. That is why, the LTC technology means a prospective base for the sustainable future operation of the current vehicles. This scientific article describes the dual-fuel technology, namely, optimization of combustion and also a design proposal of innovated geometric shape of the combustion chamber determined for minimization of gaseous emissions. An original LTC combustion system characterized by positive results achieved in the reduction of an emission footprint is introduced. This innovative system is also the subject of patent protection.
ABSTRACT
BACKGROUND: A multicenter study was conducted to test the ability of electrical impedance scanning to differentiate between benign and malignant skin lesions. The performance of a dual electrical impedance scanning/image analysis device was also assessed. METHODS: Electrical impedance scanning measurements of 449 preoperative lesions found on 382 patients and including 53 melanomas from the trunk and extremities were performed. Results were correlated with histopathologic findings. In addition, ABCD parameters for the lesions were automatically calculated by the system. RESULTS: Electrical impedance scanning detected melanomas of the trunk and extremities with 91 percent sensitivity and 64 percent specificity. Moreover, sensitivity of electrical impedance scanning was increased to 100 percent for in situ and thin melanomas of smaller size (n = 27). Visual examination identified as malignant only 67 percent of these early tumors (p = 0.002). Clinical examination detected 96 percent of the larger or thicker melanomas (n = 26), whereas electrical impedance scanning detected only 81 percent of them. Combined electrical impedance scanning and image analysis detected 100 percent of the melanomas, independent of their thickness, and with no significant decrease of specificity. Because of electrical differences between the head/neck and the rest of the body, the assessed electrical impedance scanning parameters were not adequate for the diagnosis of melanomas from the head and neck. CONCLUSIONS: A validation study proved the value of electrical impedance scanning as a noninvasive technique for detection of melanoma lesions of the trunk and extremities, specifically, of in situ and thin type. In addition, image analysis was shown to be a valuable, complementary procedure. New parameters should be designed to optimize the performance of electrical impedance scanning for melanomas of the head and neck.
