The Sources of the River Pollution

მცირე მდინარეების დაბინძურება ნავთობპროდუქტებით, გაუწმენდავი ჩამდინარე წყლებით, საყოფაცხოვრებო მყარი და თხევადი ნარჩენებით და სხვა. იწვევს დიდი მდინარეების და ბოლოს შავი ზღვის დაბინძურებას. ნაშრომში განხილულია დასავლეთ საქართველოს მცირე მდინარეების: ოღასკურა, რუა და ჩხერიმელას ეკოლოგიური მდგომარეობა.The pollution of the small rivers by petrileum products, dirty sewages and household things which are solid and liquid canses the pollution of the big rivers and the Black sea. There is reviewed in the book the ecological condition of the small rivers of Georgia such as Oghaskura, Rua, Chkherimela

Our new tornado-compatible aortic valve prosthesis: notable results of hydrodynamic testing and experimental trials

Aims A shortcoming common to all existing designs of mechanical cardiac valve prostheses is an increased trombogenicity caused, among other factors, by the lack of hydrodynamic compatibility between the luminal part of the prosthesis and the patterned blood flow. The aim of the study is to design and test our new mechanical aortic valve prosthesis to exclude life-long anticoagulation treatment. Materials and methods Standard hydrodynamic tests of the new prosthetic valve have been carried out for comparing with the other existing valve designs. A new method for the heart valve prosthesis testing in a tornado-like flow has been developed. The valve function has been verified in a swine excluding the anticoagulation treatment during the period of time exceeding six months. Results The significant advantage of the new prosthesis in the standard hydrodynamic tests has been demonstrated. The tests in the tornado-like flow have shown that only this prosthesis allows maintaining the pattern, the head and flow rate characteristics of the tornado-like jet. Upon implanting the new prosthesis in the aortic position in a swine, the good performance of the valve without anticoagulation therapy has been confirmed in the course of more than six months. Conclusion Obtained has been the evidence of the merits of the new mechanical aortic valve owing to the due consideration of the hydrodynamic peculiarities of the aortic blood flow and the creation of the design providing the proper hydrodynamic compatibility