Transparentní keramika se v laserové technice využívá jako matrice aktivních laserových prostředí vysokovýkonových laserů, kde se začala prosazovat od začátku milénia. Díky svým jedinečným vlastnostem je atraktivní alternativou monokrystalů a skel, kdy nachází využití v široké škále oborů a aplikací zahrnujících optiku, vojenství, medicínu, detektory záření a další., Transparent ceramics have been used as matrices for laser gain media of high power lasers since the beginning of this millennium. Thanks to its unique qualities it has become an attractive alternative to glasses and single crystals, finding applications in the field of optics, defence, medical facilities, radiation detectors and many others., Samuel Paul David, Petr Navrátil, Martin Hanuš, Venkatesan Jambunathan, Martin Divoký, Antonio Lucianetti, Tomáš Mocek., and Obsahuje bibliografické odkazy
Soil water availability, nutrient supply and climatic conditions are key factors for plant production. For a sustainable integration of bioenergy plants into agricultural systems, detailed studies on their water uses and growth performances are needed. The new bioenergy plant Igniscum Candy is a cultivar of the Sakhalin Knotweed (Fallopia sachalinensis), which is characterized by a high annual biomass production. For the determination of transpiration-yield relations at the whole plant level we used wicked lysimeters at multiple irrigation levels associated with the soil water availability (25, 35, 70, 100%) and nitrogen fertilization (0, 50, 100, 150 kg N ha-1). Leaf transpiration and net photosynthesis were determined with a portable minicuvette system. The maximum mean transpiration rate was 10.6 mmol m-2 s-1 for well-watered plants, while the mean net photosynthesis was 9.1 µmol m-2 s-1. The cumulative transpiration of the plants during the growing seasons varied between 49 l (drought stressed) and 141 l (well-watered) per plant. The calculated transpiration coefficient for Fallopia over all of the treatments applied was 485.6 l kg-1. The transpiration-yield relation of Igniscum is comparable to rye and barley. Its growth performance making Fallopia a potentially good second generation bioenergy crop.
Autor se v tomto článku upozorňuje na problémy související s transplantacemi, současnými zásadami, které provázejí transplantační operace, a některými úskalími právní úpravy. Kromě právní analýzy je řešena i etická analýza tohoto palčivého problému. V textu se tak autor zabývá zejména lidskou důstojností, rovností, autonomií vůle, spravedlností a právem na život a na zdraví a jejich interpretačním rámcem v kontextu s transplantacemi. V závěru poukazuje článek na filosofickou problematičnost stanovení kritéria pro určení smrti, což dopadá na současnou transplantační praxi. and Author in this article deals with issues related with organ transplantation and current leading principles in transplant laws and ethics. In this paper author analyzes issues of human dignity, equity, justice, autonomy, right to life and right to health and their context in transplant ethics. Finally this article shows some philosophical issues concerning the correct definition and standard for human death and closely connected questions with organ transplantation.
Differential pulse voltammetry with a carbon fibre microelectrode (ME) was used in pentobarbital- anaesthetized rats for monitoring the stobadine current (STB.C) on both sides of the blood-brain barrier (BBB) in the arterial bloodstream (BS) and in the corpus striatum (CS). The STB.C exhibited a distinct peak at a polarization voltage 540±30 mV (n=4). The maximum of STB.C in BS attained 2-3 min after the STB administration (2.8 mg/100 g in 1.0 ml saline solution i.a.) was followed by a rapid decrease to about 20 % within next 3 min. The STB readily passed across the BBB: the STB.C peak appeared in the CS in the 3rd minute and continued to rise up to the 30th min. The administration of STB did not prevent a large increase (1347±326 %, n=3) of the catechol-oxidative current (CA.OC) occurring in the CS between the 4th and 5th minute after cardiac arrest. However, a decrease of ME sensitivity to CA.OC in the presence of STB was observed. This fact leads to the speculation whether a similar "quenching" of dopamine by STB could not participate in the protective effects of STB observed in the brain exposed to hypoxia-reoxygenation.
This paper describes the free transverse vibration analysis of a thin circular plate, subjected to in plane stretching, whilst in interaction with a cylindrical acoustic cavity. An analysis is performed which combines the equations describing the plate and the acoustic cavity to form a matrix equation which, when solved, produces the natural frequencies (latent roots) of the coupled system and associated latent vectors which describe the mode shape coefficients of the plate. After assessing the numerical convergence of the method, results are compared with those from a commercial finite element code (ANSYS). The results analysis is then extended to investigate the effect of stressing upon the free vibration of the coupled system. and Obsahuje seznam literatury