Fast Amide Bond Cleavage Assisted by a Secondary Amino and a Carboxyl Group-A Model for yet Unknown Peptidases?

Unconstrained amides that undergo fast hydrolysis under mild conditions are valuable sources of information about how amide bonds may be activated in enzymatic transformations. We report a compound possessing an unconstrained amide bond surrounded by an amino and a carboxyl group, each mounted in close proximity on a bicyclic scaffold. Fast amide hydrolysis of this model compound was found to depend on the presence of both the amino and carboxyl functions, and to involve a proton transfer in the rate-limiting step. Possible mechanisms for the hydrolytic cleavage and their relevance to peptide bond cleavage catalyzed by natural enzymes are discussed. Experimental observations suggest that the most probable mechanisms of the model compound hydrolysis might include a twisted amide intermediate and a rate-determining proton transfer

Genetic method for optimizing the process of desulfurization of flue gases from sulfur dioxide

Sulfur dioxide is one of the most commonly found gases, which contaminates the air, damages human health and the environment. To reduce the damage, it is important to control the emissions on power stations, as the major part of sulfur dioxide in the atmosphere is produced during electric energy generation on power plants. The present work describes flue gas desulfurization process optimizing strategy using data mining. Determining the relationship between process parameters and the actual efficiency of the absorption process is an important task for improving the performance of flue gas desulfurization plants and optimizing future plants. To predict the efficiency of cleaning from SO2 emissions, a model of wet flue gas desulfurization was developed, which combines a mathematical model and an artificial neural network. The optimization modified genetic method of flue gas desulfurization process based on artificial neural network was developed. It affords to represent the time series characteristics and factual efficiency influence on desulfurization and increase its precision of prediction. The vital difference between this developed genetic method and other similar methods is in using adaptive mutation that uses the level of population development in working process. It means that less important genes will mutate in chromosome more probable than high suitability genes. It increases accuracy and their role in searching. The comparison exercise of the developed method and other methods was done with the result that the new method gives the smallest predictive error (in the amount of released SO2) and helps to decrease the time in prediction of efficiency of flue gas desulfurization. The results allow to use this method to increase efficiency in flue gas desulfurization process and to reduce SO2 emissions into the atmosphere

Modified Genetic Algorithm To Determine The Location Of The Distribution Power Supply Networks In The City

The problem of combinatorial optimization in relation to the choice of location of power supplies in solving the problem of development of urban power distribution networks is considered. Two methods of placing power supplies and securing consumers for them have been developed to solve this problem. The first developed method is to place power supplies of the same size, and the second - different sizes. The fundamental difference between the created methods and the existing ones is that the proposed methods take into account all the material of the task and have specialized ways to encode possible solutions, modified crossbreeding and selection operators. Proposed methods effectively address the problem of low inheritance, topological impracticability of the found solutions, as a result of which the execution time was significantly reduced and the accuracy of calculations increased. In the developed methods the absence of the account of restrictions on placement of new power supplies which has allowed to solve a problem of application of methods for a narrow range of tasks is realized. A comparative analysis of the results obtained by placing power supplies of the same size and known methods was performed, and it was found that the developed method works faster than known methods. It is shown that the proposed approach provides a stable convergence of the search process for an acceptable number of steps without artificially limiting the search space and the use of additional expert information on the feasibility of possible solutions. The obtained results allow to offer effective methods for improving the quality of decisions made on the choice of location of power supply facilities in the design of urban electricit

Charakter der Kraftänderung beim Rohrziehen mit Ultraschall

Mittels Ultraschallschwingungen ist es nur nur möglich, die Ziehkraft beim eingestellten Prozess zu senken, sie erlauben auch eine starke Verbesserung der Umformbedingungen in der Anfangsperiode des Ziehens, was wiederum eine Erhöhung des maximalen Umformgrades des Rohrs während eines Durchgangs ermöglicht

Fast Amide Bond Cleavage Assisted by a Secondary Amino and a Carboxyl Group—A Model for yet Unknown Peptidases?

Unconstrained amides that undergo fast hydrolysis under mild conditions are valuable sources of information about how amide bonds may be activated in enzymatic transformations. We report a compound possessing an unconstrained amide bond surrounded by an amino and a carboxyl group, each mounted in close proximity on a bicyclic scaffold. Fast amide hydrolysis of this model compound was found to depend on the presence of both the amino and carboxyl functions, and to involve a proton transfer in the rate-limiting step. Possible mechanisms for the hydrolytic cleavage and their relevance to peptide bond cleavage catalyzed by natural enzymes are discussed. Experimental observations suggest that the most probable mechanisms of the model compound hydrolysis might include a twisted amide intermediate and a rate-determining proton transfer

Ensuring food security and control of sheep and goat scrapie

In this paper, we consider the control of animal carcasses and the detection of such a disease as scrapie. For our country, this animal disease remains quite rare, but at the same time it should not be overlooked. This is due to the fact that there are regular purchases of breeding cattle from abroad, and this is a risk of importing an infected animal. The relevance of the work is that the disease of sheep and goats-scrapie can not be detected at very early stages of its development. Symptomatic manifestations do not appear immediately, there are no clear clinical characteristics, which is why this disease can not be diagnosed for a long time. To assess the health status and predict the quality of products obtained, new approaches are needed to study the products of sheep and goat slaughter. Great importance is given to standard methods of studying, identifying certain patterns in clinical, anamnestic, morphological, metric and anatomical indicators of the animal body. Using these indicators and changing their dynamic characteristics, it is possible to make significant adjustments in the definition of this disease, which would allow us to develop a number of rules for modern veterinary and sanitary evaluation of animal slaughter products

Radiation exposure does not significantly contribute to the risk of recurrence of Chernobyl thyroid cancer.

Papillary thyroid carcinoma (PTC) in patients exposed to environmental radioiodine after the Chernobyl accident is thought to have a relatively aggressive clinical course. Long-term results of treatment are not well known, especially in comparison with sporadic PTC