Although the bacterium Xanthomonas pruni utilizes the classic "tryptophan pathway" to synthesize nicotinic acid (Wilson and Henderson, J. Bacteriol. 85:221, 1963), evidence is accumulating that most bacteria do not exhibit a tryptophan-nicotinic acid relationship. The absence of such a relationship in Escherichia coli and Bacillus subtilis was reported by Yanofsky (J. Bacteriol. 68:577, 1954). ...

this paper describes a study that starts with an analysis of typical energy demand profiles in a hospital setting followed by a case study of a combined cooling, heating, and power (cchp) generation system.cchp is an autonomous system that combines the generation of electrical, heating, and cooling energy.the driving units are two high-efficiency gas engines that produce electrical and heat ene...

the remarkable development of sciences and technologies in the world of]o today has apparently brought mankind comfort and well-being, but it has also created new problems for humans including environmental pollution, widespread changes in world weather conditions, etc. fossil fuels cause numerous environmental pollutions. in other words, on the one hand poisonous gases enter the environment fo...

We determine the values of s and t for which there is a coloring of the edges of the complete bipartite graph Ks,t which admits only the identity automorphism. In particular this allows us to determine the distinguishing number of the Cartesian product of complete graphs. The distinguishing number of a graph is the minimum number of colors needed to label the vertices so that the only color pre...

There are two principal methods for the preparation of large amounts of amino acids. The first of these is synthesis by a rich variety of methods, some of which are the result of brilliant experimental work performed during the past decade by Albertson and Suter, Snyder, Dunn, Marvel, and others. It is the purpose of this paper to consider several aspects of the second principal method for the ...

The aim of this paper is to give several characterizations for the following two classes of graphs: (i) graphs for which adding any l edges produces a graph which is decomposible into k spanning trees and (ii) graphs for which adding some l edges produces a graph which is decomposible into k spanning trees. Introduction and Theorems The concept of decomposing a graph into the minimum number of ...

introduction in the wastewater treatment industry, the general attentionis mostly paidto the effluent quality standards. regardless of energy consumption, the treatment plants have been designed based on experience rather than the latest scientific findings.the treatment plants are considered as a part of energy equipment which largely consumed electrical energy.thus, electricity is the great p...

sustainable development of the production in every region requires consideration of energy flow in the production system, moreover, investigating the production system inputs from environmental management point of view is of high importance. in this study energy use and greenhouse gas emissions is investigated. data were collected through interviews with 75 tea farmers and comparing the results...