924 research outputs found
Mathematical Modeling for Studying Microbial Processes – Some Examples
Mathematical modeling may have different purposes in chemical
and biochemical engineering sciences. One of them is to confirm or to
reject kinetic models for certain processes, or to evaluate the importance of
some transport phenomena on the net chemical or biochemical reaction rate.
In the present paper different microbial processes are considered and modeled
for evaluation of kinetic constants for batch and continuous processes
accomplished by free and immobilized microbial cells. The practical examples
are from the field of wastewater treatment and biosynthesis of products,
like enzymes, lactic acid, gluconic acid, etc.
By the aid of mathematical modeling the kinetics and the type of inhibition
are specified for microbial wastewater denitrification and biodegradation
of halogenated hydrocarbons. The importance of free and immobilized
cells and their separate contribution to the overall microbial process
is also evaluated for some fermentation processes: gluconic acid production,
dichloroethane biodegradation, lactic acid fermentation and monochloroacetic acid biodegradation
GENERIC COUNSELING IN PATIENTS WITH NEUROLOGICAL DISEASES
Hereditary neurological diseases nowadays are the object of intensive clinicalgenetic and molecular-genetic research. In retrospective evaluation of500families we find out that 20 of them (4 %) are with genetically determined neuropathology. Spinal muscular atrophy and progressive muscular dystrophy (Duchenne and Becker) predominate hut there are families with neural muscular atrophy, Friedreich's ataxia, neurofibromatosis, Strumpel spastic paraparesis, myopaties (inborn and Tompson's) and Huntington's chorea. Mainly the neurological and the paediatric Clinics refer patients. Only one of the visits to the Counseling center is a result of the social contacts of the patients. Almost all autosomal dominant traits segregate in the corresponding pedigrees. Only in three families it is possible to result from a new mutation. The well-known diseases with autosomal recessive and Х-linked recessive inheritance are most often sporadic cases. In two pedigrees genetic counseling is a base for prenatal ultrasound diagnosis and in one -for DNA analysis. In the rest cases genetic prognosis is made for some family members. The concrete cases and the problems of the genetic counseling are discusse
Modeling the Demand for Qualified Personnel in the IT Industry
The author considers the problem of forecasting the demand for skills. The author’s model is a mathematical description of the movement of personnel potential of the University and of the employing organization in terms of continuous training of employees. The model describes the relationships between the structures of training, labour market, employers of University graduates. The University is viewed from two perspectives - as a staff software training and as an employer. The model is implemented in the simulation AnyLogic. The results of the scenario study the behavior of the system of reproduction of human capacity in the IT industry. As scenarios were chosen rapid, moderate growth and decline in the development of it industry, the aging workforce of the IT industry, decline in demand for the masters degree and the demand for judges from the it industry, demographic decline and growth
EVALUATION OF MEASURES TO DETECT MISAPPROPRIATION OF RESOURCES
The article presents the methodological and technical foundations of the study evaluating the effectiveness of measures to detect misuse of resources. The focus is on the algorithm steps to prepare information and conduct calculations to identify the misuse of resources. Units of analysis, conduct a technical and economic performance of the fixed assets and the most important indicators. We consider the use of performance analysis equipment on time and capacity, analysis of indicators of use of the equipment on the number, analysis of the shift index, a general analysis of return on assets, return on assets factor analysis, analysis of the effectiveness of the fixed assets. The algorithm of actions to prepare information and conduct calculations to identify the misuse of resources
Наследяване на височината на растенията и броя на листата при хибридни комбинации тютюн Виржиния
The aim of current research is to determine genetic effects in relation to inheritance of plant height and leaves number regard to their use for the Virginia tobacco breeding. The experimental work was carried out on the field of the Tobacco and tobacco products Institute, Markovo, Bulgaria. Coefficient of heritability and selection, the number of genes, transgressions and heterosis of plant height and leaves number were studied. For this purpose P1, P2, F1 and F2 populations of seven hybrid combinations were analyzed. The data from conducted analysis showed that inheritance of the plant height and tobacco leaves number is overdominantly, in the direction of the parent with the higher trait values. The number of genes influencing the plant height expression varies in a wide range (14-17) and genes number affecting tobacco leaves is 1 or 2. Negative epistasis was observed for the plant height inheritance, while epistatic interactions of genes controlling leaves number was weaker but positive one. There were establish high values for heritability coefficient of plant height and average one of leaves number. Based on the conducted analysis it was found that the mass selection by phenotype for studied traits would be more effective in the F5-F6 hybrid generations.Целта на настоящото проучване е да се установи характерът на унаследяване на височината на растенията и броят на листата при хибридни комбинации тютюн Виржиния, във връзка с тяхното използване в селекционноподобрителната работа при тази култура. Експериментът е извършен на територията на Институт по тютюна и тютюневите изделия, Марково, България. Определени са унаследяването, коефициентите за наследяемост и отбор, броят на гените, проявите на трансгресия и хетерозис по отношение на изследваните признаци при кръстоски тютюн Виржиния. За целта са проучени P1, P2, F1 и F2 популациите на седем хибридни комбинации. Данните от хибридологичния анализ показват, че при изследваните в настоящото проучване образци, унаследяването на височината на растенията и броя на листата е свръхдоминантно винаги в посока на родителя, проявяващ по-висока стойност на признака. Броят на гените, влияещи върху проявлението на признака височина на растенията е от 14 до 17, а при брой листа – 1 или 2. По отношение височината се наблюдава отрицателен епистаз, а при броя на листата, по-слаб, но положителен такъв. Установени са високи стойности за коефициента на наследяемост за височината на растенията и средни стойности относно признака брой листа от растение. Коефициентите за наследяемост и за ефективност на масовия отбор по фенотип показват, че отборът на генотипове с по-големи стойности на височината на растенията и на генотипове с по голям брой листа ще бъде по-ефективен в F5-F6 генерациите
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