Artificial heart valve was later changed to use silicone-coated material. The first implantation of mechanical heart valve to human was performed by Dr. Hufnagel on 11 September 1952, using the valve that he developed. This event accelerated the development of other artificial heart valves. Artificial heart valve An artificial heart valve is a device implanted in the heart of a patient with valvular heart disease. When one of the four heart valves malfunctions, the medical choice may be to replace the natural valve with an artificial valve. This requires open-heart surgery. Valves are integral to the normal physiological functioning of the human heart.
Animal welfare and rights in Argentina recognized the basic legal rights of an orangutan named Sandra who was born in a zoo. An advocacy group filed a petition for a writ of habeas corpus on Sandra's behalf, resulting in the court's declaration that the animal is a "non-human person". Animal welfare and rights in Argentina Animal welfare and rights in Argentina is about laws concerning and treatment of non-human animals in Argentina. Argentina has weak protections for animals by international standards. Argentina's Law 14246 (1954) prohibits cruelty toward animals. This does not include harm caused by failure to act, and it is not clear which animals