When a network begins losing nodes or links there is, eventually, a loss in its effectiveness. Thus, a communication network must be constructed to be as stable as possible, not only with respect to tlie initial disruption, but also with respect to the possible reconstruction of the network. When any disruption happens in a cornmunication network two questions are considered: How many vertices can still communicate? How difficult is it to reconnect the network? If a graph is considered as a modeling network, then the above questions can be answered by the graphs. Many graph parameters have been used to deseribe the stability of communication networks, including connectivity, integrity, and tougliness and the binding number. The thorny graphs are special classes of graphs that represent some static interconnection networks. In tliis work, we have given the tenacity of thorny graphs of static interconnection networks.
In this paper the tensor products of Hilbert modules over locally $C^{*}$-algebras are defined and their properties are studied. Thus we show that most of the basic properties of the tensor products of Hilbert $C^{*}$-modules are also valid in the context of Hilbert modules over locally $C^{*}$-algebras.
V oblasti magnetického cielenia buniek, liečiv alebo génov, využívajúc princíp magnetickej separácie vel'kým gradientom, boli navrhnuté a teoreticky analyzované nové systémy, ako aj jednoduché usporiadania magnetov, už skôr študované Halbachovo pole. Na modelovanie magnetického pol'a sa s úspechom použiva metóda konečných prvkov. Táto metóda je predmetom tohto referátu. Novým potenciálnym systémom na magnetickú separáciu v mikrometrických rozemroch je nami študované pole s ve'lkým gradientom v okolí mikrometrických diskov zo silného feromagnetika v pôvodne homogénnom poli. Bol určený približný efektívny dosah takéhoto systému v prípade nanočastíc rádovo v mikrometroch. Obdobná analýza bola vykonaná aj pre magnetické částice v prúdiacom viskóznom tekutom prostredí. Účinná separácia, resp. cielenie, v prípade malých magnetov milimetrových rozmerov v priamom kontakte s kapilárou bola dosiahnutá pre mikročastice. V podobných systémoch v centimetrových rozemroch boli pozorované porovnatel'né výsledky. Kombinácia vel'kejj intenzity a gradientu je dosiahnutá len v blízkom okolí magnetov. Väčší dosah bol pozorovaný v prípade študovaného symetrického Halbachovho pol'a., The magnetic particles play an important role as magnetic drug, gene or cell carriers, in biomedicine and biotechnology. Their combination with a strongly non-homogeneous magnetic field is considered as a powerful way to target them to desired sites in living organism. It is important to know the potential applicability of these systems for magnetic drug targeting in living organism. For these purposes we have developed and evaluated a numerical model of magnetic targeting using finite element method applied to solve Maxwell equations describing electromagnetic field coupled with Newton law of particle motion., Andrej Krafčík, Melánia Babincová, Peter Babinec., and Obsahuje bibliografii
Nedávno jsme si mohli přečíst v Československém časopise pro fyziku pěkný článek o fyzikálních principech fotovoltaické přeměny energie ve fotovoltaických (PV) článcích na bázi polovodičových diod [1]. Tímto článkem bychom na tuto problematiku rádi navázali a vysvětlili, jak závisí důležité parametry PV článků na teplotě. Tyto závislosti se totiž významně projevují v reálném provozu PV elektráren., I-V characteristic of illuminated photovoltaic cells vary with temperature. At high temperatures, there is a lower open-circuit voltage and higher short-circuit current. This behavior can be explained using band theory of solid state physics. An increasing temperature causes a narrowing of the forbidden gap and a shift in the Fermi energy level toward the center of the forbidden gap. Both of these effects lead to a reduction in the potential barrier in the band diagram of the illuminated PN junction, and thus decreases the photovoltaic voltage. In addition, the narrowing of the forbidden gap causes higher generation of electron-hole pairs in the illuminated PN junction, and therefore the short-circuit current increases. Understanding of this mechanism is important, as at higher temperatures, photovoltaic energy conversion has lower efficiency., and Martin Libra, Vladislav Poulek, Pavel Kouřím.
Using specialized sources such as legionary literature (a vast sub-genre of Czech fi ction between the two world wars), memoirs, diaries, photographs, and personal effects, the author seeks in this article to portray the everyday life of the Czechoslovak legionaries in Russia from 1918 to 1920. To a considerable extent their lives were linked to their being moved about by train. At the centre of this were the tepluskas, furnished and heated box cars, part of the eshelons (troop trains), which served as the makeshift homes in which they spent most of their time. The Czechoslovak volunteers boarded the tepluskas in the spring of 1918, after retreating from the troops of the Central Powers in Ukraine. They then headed for Vladivostok, where they were meant to board ship and sail to France. As things turned out, however, the legionaries remained in Russia far longer, and fought in battles against the Bolsheviks, at fi rst to save themselves, but later, on the side of the Entente, in support of Masaryk’s foreign policy and the creation of an independent Czechoslovakia. The author concentrates more on the living conditions, activities, and customs of the legionaries in tepluskas. He discusses the furnishings of them, the way they were decorated, and their adaptation to the current needs of the legionaries. Last but not least, he attempts to describe how the legionaries experienced their milieu and how it infl uenced their lives together. The author seeks to provide a vivid picture of the “army” on wheels, which changed considerably over time.
Glucose tolerance, serum insulin, insulin receptors in epididymal fat tissue, circulating total cholesterol and triglyceride concentrations as well as serum prolactin were studied in obese and lean spontaneously hypertensive rats (SHR) of both sexes. Obese animals displayed insulin resistance and elevated insulin and triglyceride concentrations. Moreover, in obese rats the increased mass of epididymal fat tissue was accompanied with decreased capacity of high affinity binding sites of insulin receptors in the tissue plasma membranes. Terguride treatment lowered prolactin serum levels which was accompanied by ameliorated insulin sensitivity in obese animals of both sexes. In addition, terguride treatment decreased serum insulin and triglyceride concentrations in obese females and at the same time enhanced the affinity of high affinity insulin binding sites. Our results show that obesity in SHR is associated with a decreased capacity of insulin receptors and that prolactin may play a role in obesity-induced insulin resistance, particularly in female rats., V. Golda +, M. Ficková, L. Pinterová, J. Jurčovičová, L. Macho, Š. Zórad., and Obsahuje bibliografii
We investigate the factor of the groupoid of terms through the largest congruence with a given set among its blocks. The set is supposed to be closed for overterms.
The terminal phase of the migration of Trichobilharzia regenti Horák, Kolářová et Dvořák, 1998 in the definitive host (Anas platyrhynchos f. domestica) was studied 12-27 days post infection (p.i.). Brain meninges were the last part of the nervous system where the worms were detected before their occurrence in the nasal cavity. In meninges, the parasites started to feed on red blood cells. Then the worms occurred in the nasal mucosa 14-25 days p.i. and the first immature eggs appeared 15 days p.i. The fully developed miracidia were recorded in the eggs from 17 days p.i. and freely in the nasal mucosa 19 days p.i. Infiltrates of lymphocytes, later also eosinophils and heterophils around the eggs and free miracidia, were observed from 15 and 19 days p.i., respectively. The haemorrhages occurring from 17 days p.i., and the granulomas with lymphocytes, eosinophils and heterophils forming around the eggs from 22 days p.i. were the most apparent pathological changes of nasal tissue.