Vanadium-binding proteins, or Vanabins, have recently been isolated from the vanadium-rich ascidian, Ascidia sydneiensis samea. Recent reports indicate that Vanabin2 binds twenty V(IV) ions at pH 7.5, and that it has a novel bow-shaped conformation. However, the role of Vanabin2 in vanadium accumulation by the ascidian has not yet been determined. In the present study, the effects of acidic pH ...

A novel compound, for which the trivial name tunichrome is proposed, was isolated from the vanadium-rich blood cells of the tunicate Ascidia niga. Preliminary structural studies suggest a molecular weight of about 390, the presence of conjugated vinyl groups, and an acidic group, possibly carboxyl, with an apparent pKa of 3.0. Elements C, H, N and O comprise 98.4% of the sample weight, the numb...

large cities and metropolitan areas in developing countries are growing rapidly. these areas grew by attracting all facilities, services and capital of the country. tehran has been the major city and center for decision and policy making in various administrative, political, economic and socialaspects. this political focus has brought economic, social, educational focus that attracted a vast ma...

In today's highly competitive higher education landscape, the increasing number of universities offering similar programs has intensified competition for prospective students. As a result, students have become more selective in choosing their educational institutions. To attract interest students, need to differentiate themselves through effective marketing messages and strategies. This study f...

The Covid-19 pandemic has impacted negatively on our society and resulted in numerous deaths. It had an effect on every facet of health-care delivery. Rules, regulations, and payment policies were changed to allow extensive use of telecommunications technology in lieu of in-person clinical visits to protect health care personnel and patients throughout the country from the risk of disease trans...