Ochorenia myelínu CNS sa súhrnne označujú ako leukoencefalopatie. Termín zahŕňa poruchy, pri ktorých zmeny v bielej hmote prevažujú alebo sú výlučné, pričom patofyziologický mechanizmus ani histopatologická báza nie sú rozhodujúce. Z tejto širokej skupiny vrodených a získaných porúch sa vyčleňuje skupina leukodystrofií, ktorá označuje primárnu poruchu myelínu a buniek tvoriacich myelín. Klasicky sa do tejto skupiny radí šesť klinických jednotiek: X‑adrenoleukodystrofia, metachromatická leukodystrofia, Krabbeho globoidná leukodystrofia, Canavanovej choroba, Pelizaeus‑Merzbacherova choroba a Alexandrova choroba. Pribúdajúcimi poznatkami sa skupina rozširuje o stále nové primárne poruchy. Pre presnú diagnostiku je dôležitý klinický nález, významné sú zmeny na MR mozgu a laboratórne vyšetrenia. Precíznou analýzou MR obrazu je možné diagnostický proces urýchliť. Jedným zo spoločných znakov leukodystrofií je progresívny priebeh. U detí nastáva zväčša rýchla strata motorických a kognitívnych funkcií. V prípade adolescentov a adultných pacientov je ťažisko zmien v psychickej a mentálnej oblasti, pričom motorický deficit nastupuje neskôr. Priebeh X‑adrenoleukodystrofie, metachromatickej leukodystrofie, Krabbeho globoidnej leukodystrofie sa dá vo včasnom štádiu alebo predklinickom období ovplyvniť transplantáciou kostnej drene alebo kmeňových buniek. V prípade metachromatickej leukodystrofie je v skorých štádiách indikovaná génová a enzýmová terapia. Pre ostatné leukodystrofie je dostupná len symptomatická liečba. Cieľom práce je zhrnutie najdôležitejších poznatkov a liečebných možností., Myelin disorders of the central nervous system are also known as leukoencephalopathies. This term includes diseases, in which changes of the white matter are dominant, or even exclusive, while neither the pathophysiological mechanism nor the histopathological basis are decisive. This broad selection of inborn and acquired disorders includes a group of leukodystrophies characterized by primary dysfunction of myelin and myelin-producing cells. Typically, six separate clinical entities are included in this group: X-linked adrenoleukodystrophy, metachromatic leukodystrophy, Krabbe’s globoid cell leukodystrophy, Canavan disease, Pelizaeus-Merzbacher disease and Alexander disease. The group is constantly expanding as our knowledge develops. Clinical and laboratory findings, as well as MRI scans, are crucial for exact diagnosis. Accurate analysis of MRI images accelerates the diagnostic process considerably. A common feature of leukodystrophies is their progressive nature. Children exhibit rapid loss of motor and cognitive functions. In adolescent and adult patients, psychological and mental changes are the most prominent, while motor deficit has a later onset. The course of X-linked adrenoleukodystrophy, metachromatic leukodystrophy, and Krabbe’s leukodystrophy can be managed at the early or pre-clinical stages with bone marrow or stem cell transplantation. Gene and enzyme therapy are indicated at the earliest stages of metachromatic leukodystrophy. For the remaining leukodystrophies, only symptomatic therapy is available. The purpose of this paper is to summarize current information and knowledge as well as possible therapeutic options in this group of disorders., Vědomostní test, and M. Kolníková, P. Sýkora
Causal overdetermination - i.e. instances in which x, y, and z all occur and intuitively the occurrence of x alone is sufficient for the occurrence of z and the occurrence of y alone is sufficient for the occurrence of z - has long been considered a problem for counterfactual analyses of causation. Intuitively, we want to say both x and y caused z, but standard Lewisian counterfactual analysis yields the result that neither x nor y caused z. David Lewis, himself, suggested that overdetermination ought to be left as ''spoils to the victor''. I show how, if we modify Lewis’ account of events slightly, we can bring counterfactual analysis in line with our intuitions about overdetermination., Kauzální overdetermination - tj. Případy ve kterých x, y, a z všichni nastanou a intuitivně výskyt x sám je dostačující pro výskyt z a výskyt y sám je dostačující pro výskyt z - dlouho byl zvažován problém pro \ t kontrafaktuální analýzy příčin. Intuitivně chceme říci, že jak x, tak y způsobily z, ale standardní Lewisianova kontrafaktuální analýza dává výsledek, že ani x ani y nezpůsobily z. David Lewis, sám, navrhl, že nadměrné určování by mělo být ponecháno jako ,,kořist pro vítěze''. Ukazuji, jak kdybychom pozměnili Lewisův účet o událostech, můžeme přinést kontrafaktuální analýzu v souladu s našimi intuicemi o předávkování., and Dana Goswick
In this paper, I examine two non-Gricean approaches to the evolution of human communicative abilities: Mitchell S. Green’s ac- count of organic meaning and Dorit Bar-On’s account of expressive communication. I argue that the non-Gricean approaches in question face certain problems: i) they focus on the adaptive function of communicative behaviours and ignore questions about their mechanisms, ontogeny and phylogeny; ii) the notion of organic meaning does not constitute an intermediate form between natural and non-natural meaning but should rather be understood as a special case of natural meaning; iii) the non-Gricean approaches under scrutiny cannot ex- plain the transition from dyadic to triadic communication. I also outline the differences between Gricean and non-Gricean approaches and argue against the usefulness of the non-Gricean approaches discussed in this paper in explaining the evolution of human communicative abilities.
A bend or any another pipe component disturbs solids transport in pipes. Longitudinal pressure profiles downstream of such a component may show a stationary transient harmonic wave, as revealed by a recent settling slurry laboratory experiment. Therefore the fundamental transient response of the two-layer model for fully stratified flow is investigated as a first approach. A linear stability analysis of the sliding bed configuration is conducted. No stationary transient harmonic waves are found in this analysis, but adaptation lengths for exponential recovery are quantified. An example calculation is given for a 0.1 m diameter pipeline. Also consequences for long stretches of pipe line emerged. A so far undiscovered exclusion zone is found in the I-V diagram. This exclusion zone is situated adjacent to the deposit limit velocity locus curve. This simplified physical system reveals that flow velocities should be taken about 10% greater than the calculated maximum deposit limit velocity for stable converging flow.
Development of any area often leads to more intensive land use and increase in the generation of pollutants. Modeling these changes is critical to evaluate emerging changes in land use and their effect on stream water quality. The objective of this study was to assess the impact of spatial patterns in land use and population density on the water quality of streams, in case of data scarcity, in the Chugoku district of Japan. The study employed artificial neural network (ANN) technique to assess the relationship between the total phosphorous (TP) in river water and the land use in 21 river basins in the district, and the model was able to reasonably estimate the TP in the stream water. Uncertainty analysis of ANN estimates was performed using the Monte Carlo framework, and the results indicated that the ANN model predictions are statistically similar to the characteristics of the measured TP values. It was observed that any reduction in forested area or increase in agricultural land in the watersheds may cause the increase of TP concentration in the stream. Therefore, appropriate watershed management practices should be followed before making any land use change in the Chugoku district. and Rozvoj územia často súvisí so zintenzívnením využívania krajiny a produkciou znečistenia. Dôležité je modelovanie týchto zmien a ich vplyvu na kvalitu vody v tokoch. Cieľom štúdie je určiť vplyv priestorových zmien pri využívaní krajiny a zmeny hustoty osídlenia na kvalitu vody v tokoch v čase nedostatku vody v oblasti Chugoku, Japonsko. Pri riešení sa využívajú umelé neurónové siete (artificial neural network -ANN), prostredníctvom ktorých sa určuje vzťah medzi celkovým obsahom fosforu (TP) v toku a využívaním kajiny v 21 povodiach oblasti; tento model je schopný vypočítať TP v tokoch. Analýza neurčitosti výsledkov dosiahnutých pomocou ANN bola vykonaná metódou Monte Carlo; výsledky analýzy naznačujú, že predpovede pomocou metódy ANN sú štatisticky podobné meraným hodnotám TP. Bolo zistené, že redukcia lesnatosti a zvýšenie plochy poľnohospodársky využívanej pôdy v povodí môže viesť k zvýšeniu koncentrrácie TP v toku. Je preto potrebné pred zmenou vo využívaní krajiny prijať zodpovedajúce opatrenia v manažmente krajiny, ktoré budú minimalizovať negatívne dôsledky zmien využívania krajiny.
The study aimed to determine the linkage between soil exchangeable potassium (K+) concentration and stream water K+ concentration during rainfall and snowmelt events in small catchments with different land use (Carpathian Foothills, Poland). The complementary geochemical and hydrochemical approach used in the study produced new information on the role of particular soil horizons and contributing areas such as hillslope or riparian areas in K+ delivery to stream channels during events. Horizons lying above the nearly impermeable fragipan (Btx) play the most important role in the process of K+ influx to streams during most event types except snowmelts with frozen soils, in all the studied catchments. In the woodland catchment, rapid flushing of K+ from the topsoil Ah horizon with higher hydraulic conductivity (Ksat) and higher exchangeable K+ concentrations than in the lying lower E horizon resulted in a clockwise hysteresis of K+ in stream water during most events. In agricultural catchments, changes in stream water K+ concentration during events were determined by distinct differences between soil exchangeable K+ concentrations on hillslopes and in riparian areas.