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Effect of selected abiotic factors on wing polymorphism of semiaquatic bug Microvelia reticulata Burmeister, 1835.
ČERMÁKOVÁ, Táňa
Wing polymorphism of semiaquatic bugs is affected by environmental factors as temperature, photoperiod, population density or permanency of habitat. The heritability has its own specific part, too. A lot of field studies suggest that crucial effect on wing polymorphism has temperature, but laboratory experiments often do not confirm this hypothesis. The main aim of this thesis was to describe the effect of environmental factors (photoperiod, temperature and permanency of habitat) on wing polymorphism of Microvelia reticulata, additionally of Gerris lacustris. The partial tasks included description of effect of mentioned abiotic factors on mortality and rate of development. The individuals of both species were kept at combinations of two levels of temperature, photoperiod and permanency of habitat (overall at eight treatments) from first larval instar to adult. All adults of Microvelia reticulata emerged as apterous, so there was no response of wing polymorphism to tested environmental factors. The main influence of heritability is presumable. Only ten individuals of G. lacustris developed into the adult stage, so it was impossible to describe the influence of abiotic factors on wing polymorphism, mortality and lenght of development in this species. Mortality of individuals of M. reticulata was significantly influenced by the type of substrate. Only 3.5% of individuals survived when reared on wet filter paper, while 80.5% on the water surface. Both other factors (temperature, photoperiod) had no effect on total mortality. There was no difference between mortality of males and females, so it is impossible to note sexual dependent mortality. The lenght of development did not differ between sexes either. Lenght of development was significantly affected by temperature, as low temperature reduces development of M. reticulata. The fastest development showed nymphs of second instar and slowest development nymphs of fifth instar at all treatments. Since the effect of abiotic factors on wing polymorphism was not found in M. reticulata, it would be sufficient to study the effect of heritability on development of wings in this species in the future.
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Good manufacturing and hygienic practices with processing of freshwater fish.
SMOLA, Jiří
HACCP and good manufacturing practices are tools to the safeguard of food safety. Technologic process of fish processing begins by receiving of live fish and ending with stock and expedition of fish products. Stocking is the operation, whereat is able to get to consumer{\crq}s health hazard. Wrong temperature regulation causes multiplication of microorganisms. Stocking proceed at temperature 0 {--} 2 °C, which is stopping increasing of microorganisms. Practically were tracked difference course temperatures during hours and days. During monitoring was average temperature at 10 AM 2.33 {$\pm$} 1.25°C and average temperature at 10 PM was 2.11 {$\pm$} 1.19°C. During monitoring was average temperature 2.10 {$\pm$} 1.03°C. Maximum temperature was monitored in the morning. The temperature raised trough storage of new products. This short - period increasing is able to influence quality of products.
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Měření excitačních a ionizačních teplot v expandujícím proudu H2O-Ar plazmatu
Sember, Viktor ; Mašláni, Alan
Optical emission spectroscopy is used to determine the temperature in a plasma jet expanding from the H2O-Ar dc arc torch into a chamber maintained at a pressure of 10 kPa. The excitation and rotational temperatures are derived from relative intensities of argon atomic and ionic lines, and from the UV OH band at 306.357 nm, respectively. The ionization temperature is obtained from the intensity ratio of argon ionic and atomic lines, using electron number density calculated from the Stark broadening of hydrogen H line. The structure of the plasma jet is characterized by isocontours of electron number density and intensity of atomic and ionic lines. In the expansion region, the ionic excitation temperature is found close to the ionization temperature and much higher than the excitation temperature of argon atoms, which is close to the rotational temperature of OH radical. In the normal shock region, all the measured temperatures tend to be equal.
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Mapování teplotního a rychlostního pole ve volném proudu horkého plynu
Gregor, Jan ; Jakubová, I. ; Mendl, T. ; Šenk, J.
In the paper the measurements on hot gas mixture free jet are analyzed. The main interest is oriented on the analysis of the distribution of the individual species in the jet based on the vector form of the continuity and momentum equation. In the continuity equation the diffusion member is involved. To simplify the problem, the temperature and velocity fields are approximated by suitable functions. The calculation process is applied on the jet generated by a hybrid water stabilized plasma torch with argon added into the chamber of a plasma heater.
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