Influenza A virus Essay Example | Topics and Well Written Essays - 500 words

Influenza A virus - Essay Example The envelope has two surface glycoproteins called neuraminidase and hemagglutinin, the latter gets attached to the host cell prior to viral penetration. Often the HA protein undergoes several antigenic changes, such genomic alterations lead to phenotypic changes thus challenging the development of vaccines against influenza virus. [A. Maher and A virulent influenza A virus in humans is responsible for the infection of the respiratory tract leading to necrosis of the epithelial tissues. The infection then extends to the bronchioles and alveoli resulting in interstitial pneumonia. A susceptibility to bacterial super infection is not uncommon. The infection slowly affects extra respiratory tissues leading to myocarditis, myositis, parotitis, encephalopathy and Reye-Jhonson syndrome. [T. Kuiken, G. F. Rimmelzwaan, G. Van Amerongen and A. D. M. E. Osterhaus] For most experimental studies concerned with animal models, mouse is widely used .The low cost combined with its small size permits researchers to conduct large scale studies. Mouse is also considered suitable as a mammalian model for the studies concerning pathogenesis and immunity of human H5N1 influenza virus mainly due to the fact that this virus replicates very effectively and efficiently in the lungs of mouse without any adaptation.

Topic selection and statement of problem Assignment

Topic selection and statement of problem - Assignment Example ystem can be defined as a personnel system applied in the process of hiring and promoting government employees based on merit to obtain the highest efficiency in public personnel functions. The application of the merit system in the public education sector has brought about unending controversies especially with the merit pay issue. The merit pay systems emphasizes on the fact that teachers are to be paid for their achievement in the classroom as opposed to their seniority or the number of ed-school credits that they have collected as it has been done from the 1920s period. Reformers in the education system including the government have emphasized that the merit pay will encourage high performing teachers to do well and drive the lazy ones away, thereby improving the performance of public schools. However, teachers’ unions have continually opposed the move stating that there is no objective way of measuring the classroom performance of a teacher. In addition to this, opposing views have pointed to the fact that the merit pay system has a high chance of failing especially because of issues of supervisor bias or favoritism (Gratz, 2009). The merit pay has proven to be productive especially in the private sector where it has been applied since the 1980s. The growth of international economic competition made U.S. corporations to measure indicial worker performance and introduced pay incentives based on work output to motivate employees to perform better. This practice has gone on up to the present day where new performance criteria have been implemented with multi-faceted compensation plans for the highly performing employees (Ritter & Barnett,  2013). The public education monopoly has resisted the merit pay proposal because of the fears that it may lead to biases and unfair treatment of teachers. However, pilot studies carried out, such as those done in Cincinnati’s public school system have proven successful. The merit pay system is relevant for the study of