Essential nutrient is nutrient needed for functioning of body which cannot be synthesized by on its own. Different categories include dietary minerals, vitamins essential amino acids and fatty acids. Many essential vitamins includes vitamin C. various nutrients comes from different species. High-impact journals are those considered to be highly influential in their respective fields. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.
Last date updated on September, 2014