Different expressions of trypsin and chymotrypsin in relation to growth in Atlantic salmon (Salmo salar L.)

The expressions of trypsin and chymotrypsin in the pyloric caeca of Atlantic salmon (Salmo salar L.) were studied in three experiments. Two internal (trypsin phenotypes, life stages) and three common external factors (starvation, feeding, temperatures) influencing growth rates were varied. Growth was stimulated by increased temperature and higher feeding rate, and it was depressed during starvation. The interaction between trypsin phenotype and start-feeding temperature affected specific activity of trypsin, but not of chymotrypsin. Trypsin specific activity and the activity ratio of trypsin to chymotrypsin (T/C ratio) increased when growth was promoted. Chymotrypsin specific activity, on the other hand, increased when there was a reduction in growth rate whereas fish with higher growth had higher chymotrypsin specific activity resulting in lower T/C ratio value. During a rapid growth phase, trypsin specific activity did not correlate with chymotrypsin specific activity. On the other hand, a relationship between specific activities of trypsin and chymotrypsin could be observed when growth declined, such as during food deprivation. Trypsin is the sensitive key protease under conditions favouring growth and genetically and environmentally affected, while chymotrypsin plays a major role when growth is limited or depressed. Trypsin specific activity and the T/C ratio value are shown to be important factors in the digestion process affecting growth rate, and could be applicable as indicators for growth studies of fish in captive cultures and in the wild, especially when food consumption rate cannot be measured

THEORETICAL COMPLEX ENERGIES OF STARK RESONANCES IN LITHIUM BY OPERATOR PERTURBATION THEORY APPROACH

The theoretical complex energies of the Stark resonances in the lithium atom (non-hydrogenic atomic system) in a DC electric are calculated within the operator form of the modified perturbation theory for the non-H atomic systems. The method includes the physically reasonable distorted-waves approximation in the frame of the formally exact quantum-mechanical procedure. The calculated  Stark resonances energies and widths in the lithium atom are calculated and compared with  results of calculations on the basis of the  method of  complex eigenvalue Schrödinger equation by Themelis-Nicolaides, the complex absorbing potential method by Sahoo-Ho and the B-spline-based coordinate rotation method approach  by Hui-Yan Meng et al.    Вычислены значения комплексных энергий штарковских резонансов в атоме лития (многоэлектронная атомная система) в постоянном  электрическом поле на основе модифицированной операторной теории возмущений для многоэлектронных атомных систем. Теоретический подход включает физически обоснованное приближение искаженных волн в рамках формально точной квантово-механической процедуры.  Энергии и ширины штарковских резонансов в спектре атома лития вычисляются и сравниваются с результатами расчетов в рамках метода комплексного оптического потенциала, обобщенного метода  вращения координат с использованием В сплайнового алгоритма и данными прямого вычисления собственных значений  комплексного уравнения Шредингера.Обчислені значення комплексних енергій штарківських резонансів в атомі літію (багатоелектронних атомна система) в постійному електричному полі на основі модифікованої операторної теорії збурень для багатоелектронних атомних систем. Теоретичний підхід включає фізично обґрунтоване наближення перекручених хвиль в рамках формально точної квантово-механічної процедури. Енергії і ширини штарківських резонансів в спектрі атома літію обчислюються і порівнюються з результатами розрахунків в рамках методу комплексного оптичного потенціалу, узагальненого методу обертання координат з використанням В-сплайнового алгоритму і даними прямого обчислення власних значень комплексного рівняння Шредінгера

SPECTROSCOPY OF MULTIELECTRON ATOM IN DC ELECTRIC FIELD: RELATIVISTIC OPERATOR PERTURBATION THEORY

We develop the theoretical basis of a new relativistic operator perturbation theory  approach to multielectron atom in a DC electric field combined with a relativistic many-body perturbation theory formalism for a free multielectron atom. As illustration of application of the presented formalism, the results of energy and spectral parameters for a number of atoms are presented. The relativistic  OPT  method is tested for computing the Stark shifts of Rydberg states for a few the multielectron systems such as the sodium and rubidium. The approach allows an accurate and consistent treatment of a DC strong field Stark effect in multielectron atoms