In this paper, I aim to do three things. First, I introduce the distinction between the Uniqueness Thesis (U) and what I call the Conditional Uniqueness Thesis (U*). Second, I argue that despite their official advertisements, some prominent uniquers effectively defend U* rather than U. Third, some influential considerations that have been raised by the opponents of U misfire if they are interpreted as against U*. The moral is that an appreciation of the distinction between U and U* helps to clarify the contours of the uniqueness debate and to avoid a good deal of talking past each other.
Molecular analysis of an extensive specimen collection of morphologically distinct tapeworms of the genus Caryophyllaeus Gmelin, 1790 (Cestoda: Caryophyllidea), parasites of cyprinid fishes in the Palaearctic Region, brought evidence of host-related plasticity in critical morphological characters widely used for species circumscription and classification of these tapeworms. The results obtained here do not support the traditionally used morphological concept of species-defining characters of the order Caryophyllidea Carus, 1863, especially due to high morphological plasticity of the scolex and the anterior end of the body. Several morphotypes within both Caryophyllaeus laticeps (Pallas, 1781) and Caryophyllaeus brachycollis Janiszewska, 1953 generally corresponding to different hosts and geographical regions, were recognised likely suggesting host- and geography-related intraspecific morphological variability. Genetic data confirmed euryxenous host specificity of both species, most profoundly C. laticeps, but did not support the existence of cryptic species. In fact, some of the fish hosts may harbour both of the congeneric species including several of their respective morphotypes. The pattern of morphological and genetic divergence observed in both cestode species studied indicates a scenario of possible host range extensions and subsequent parasite diversification. If molecular sequence variability and host-related morphological polymorphism are confirmed in other groups of monozoic cestodes, it may complicate species identification and straightforward classification of these parasites.
Climate changes expected in future would influence the inflow into a multipurpose reservoir. Will be a reservoir able to supply a real demand for water during those climate conditions? This ability was calculated by rainfall-runoff balance model WBMOD that works with a monthly time step. The input data series of precipitation and air temperature and the observed reservoir outflows were used to express the expected changes of the total runoff and the required reservoir capacity. Input data were modified every month according to the last climate scenarios CCCM2000 and GISS1998 estimated for the Vihorlat reservoir catchment. Failures in the required water supply in volume and time for these changed climate conditions were evaluated. Climate scenarios of temperature and precipitation changes for the Laborec catchment above gauging station Laborec-Humenné, for time period 1971-1998 were used. and Zmena klímy očakávaná v budúcnosti by mohla ovplyvniť aj prítok do vodnej nádrže. Bude za takýchto klimatických podmienok nádrž schopná zabezpečiť reálne požiadavky na vodu, aké boli namerané za jej doterajšej prevádzky? Na výpočet týchto zmien bol použitý zrážkovo-odtokový bilančný model WBMOD pracujúci v mesačnom kroku. Zmeny celkového odtoku z povodia a požadovaného objemu nádrže na zabezpečenie reálneho odberu boli vyčíslené za pomoci vstupných údajov o zrážkach a teplotách v povodí Laborca nad profilom Humenné a za pomoci meraných odberov z vodnej nádrže Vihorlat (Zemplínska Šírava) za obdobie 1971-1998. Vstupné údaje boli modifikované podľa najnovších klimatických scenárov CCCM2000 a GISS1998 prepočítaných pre povodie Laborec-Humenné. Na záver boli vyčíslené nedodávky požadovaného množstva vody v objeme a čase za zmenených klimatických podmienok.
The proportional light absorptance by photosynthetic tissue (α) is used with chlorophyll (Chl) fluorescence methods to calculate electron transport rate (ETR). Although a value of α of 0.84 is often used as a standard for calculating ETR, many succulent plant species and species with crassulacean acid metabolism (CAM) have photosynthetic tissues that vary greatly in color or are highly reflective, and could have values of α that differ from 0.84, thus affecting the calculation of ETR. We measured ETR using Chl fluorescence and α using an integrating sphere in 58 plant species to determine the importance of applying a measured value of α when calculating ETR. Values of α varied from 0.55-0.92 with a mean of 0.82 across species. Differences between ETR values calculated with measured α values ranged from 53% lower to 12% greater than ETR values calculated with a standard α value of 0.84 and were significantly different in 39 out of 58 species. While measurements of ETR using Chl fluorescence represent a rapid and effective assessment of physiological performance, the value of α needs to be considered. Measurements of α, especially on species with light-colored or reflective photosynthetic tissue, will allow more accurate determination of photosynthesis in succulent and CAM species. and J. A. Stemke, L. S. Santiago
The paper presents the results of the study of the sediments deposition process in a settling basin by using a k-ε turbulence model. The results obtained are than compared with the results obtained by using 1 and 2 D mathematical models and field measurements. In the first step, the settling basin is designed based on the formulae recommended by classical approach. The transition zone at the entrance of settling basin is then adjusted to satisfy more uniform flow at the beginning of the active zone. The flow velocity variation and bed shear stress distribution over the cross section area are furthermore analyzed and questions suggesting further development of mathematical models are identified. For the second step, a schematized settling basin is then modelled in three-dimensional laterally confined model for the purpose of dealing with turbulences that potentially bring more sediment to the side and to the end of settling basin. Finally, recommendations for the design of settling basin are given by analyzing the results obtained by both mathematical and empirical methods. By comparison of the results obtained and field measurements made in Indonesia, useful design recommendations are derived. and Príspevok obsahuje výsledky štúdia sedimentačného procesu v usadzovacej nádrži s využitím modelu turbulencie k-ε. Takto získané výsledky sú porovnané s tými, ktoré boli získané pomocou jedno- a dvojdimenzionálneho modelu a s terénnymi meraniami. Najskôr bol sedimentačný bazén navrhnutý pomocou klasických vzorcov. Prechodová zóna a vstup do usadzovacieho bazénu bol potom upravený tak, aby zabezpečil relatívne homogénne prúdenie na začiatku aktívnej zóny. Boli analyzované zmeny rýchlosti prúdenia a rozdelenie trecích napätí na dne v priečnych rezoch koryta a boli identifikované problémy, ktoré by umožnili ďalší vývoj matematických modelov tohto javu. V ďalšom kroku bol modelovaný schematizovaný usadzovací bazén ako trojrozmerný, na oboch stranách ohraničený model, aby sa dalo manipulovať s turbulenciou, ktorá by mohla potenciálne dopraviť viac sedimentov na strany a na koniec sedimentačnej nádrže. Nakoniec uvádzame odporúčania pre návrh sedimentačných nádrží, vychádzajúc z výsledkov využitia matematických aj emprických metód. Porovnaním týchto výsledkov s výsledkami terénnych meraní v Indonézii boli navrhnuté užitočné odporúčania.
The principle, relevant theory and properties of the considered actual light reflectance digital imaging colorimetry by means of a suitable three-channel (3CCD) digital color camera are described in the present article. These aspects relate to the chosen commonly acceptable idealized linear model of camera color operations with respect to the standard observer and camera spectral response functions, spectral power density of the illuminant and spectral reflectance of the color sample surface at each pixel location in the camera image plane. The introduced optimal mathematical expressions of analytical and matrix forms relate to the CIE tristimulus color coordinates (X, Y, Z), the camera (R, G, B) digital output color data and the spectral reflectance of a color sample. Their useful relationships are ensured by exploitation of a suitable mean-squares approximation. The linearly combined solutions, proposed in this article, are a useful extension of other approaches in branches dealing with light reflectance color samples. and Prezentovaný článek popisuje princip, příslušnou teorii a vlastnosti uvažované současné světloodrazivé digitální zobrazovací kolorimetrie využívající vhodnou tříkanálovou (3CCD) digitální barevnou kameru. Tato hlediska se vztahují ke zvolenému obvykle přijatelnému idealizovanému lineárnímu modelu kamerových činností se zřetelem k spektrálním funkcím odezvy standardního pozorovatele a kamery, spektrální hustotě výkonu osvětlovače a spektrální odrazivosti povrchu barevného vzorku pro každou pixelovou polohu v obrazové rovině kamery. Zavedené optimální matematické výrazy v analytických a maticových formách se vztahují k CIE třístimulačním barevných souřadnicím (X, Y, Z), výstupním barevným datům (R, G, B)CCD kamery a spektrální odrazivosti barevného vzorku. Jejich užitečné závislosti jsou zajištěny využitím aproximační metody minima středních kvadratických odchylek. Lineárně kombinovaná řešení, navržená v tomto článku, jsou užitečným rozšířením jiných přístupů v odvětvích s reflexními barevnými vzorky.
Muscarinic acetylcholine receptors in the heart have been shown to display agonist-independent spontaneous (constitutive) activity which causes changes in the opening of cardiac ion channels and in the activity of G proteins. We investigated whether an inhibition of the constitutive activity of muscarinic receptors induced by the binding of antagonist brings about a change in the synthesis of cyclic AMP in rat cardiac membranes, and whether the action of the antagonist is stereospecific. Atropine and S-(-)-hyoscyamine were indeed found to enhance the forskolin-stimulated synthesis of cyclic AMP in rat cardiac (both atrial and ventricular) membranes by up to 24%. The effect was stereospecific and the potency of R-(+)-hyoscyamine was 30 fold lower than that of the S-(-) enantiomer, confirming that the action of hyoscyamine is receptor-mediated. The effect did not depend on the presence of endogenous acetylcholine in the system used. The results strongly suggest that the adenylyl cyclase in the heart is exposed to continuous mild inhibition by constitutively active muscarinic receptors in the membranes of cardiomyocytes., J. Říčný, F. Gualtieri, S. Tuček., and Obsahuje bibliografii
This paper focuses on the constrained optimality of discrete-time Markov decision processes (DTMDPs) with state-dependent discount factors, Borel state and compact Borel action spaces, and possibly unbounded costs. By means of the properties of so-called occupation measures of policies and the technique of transforming the original constrained optimality problem of DTMDPs into a convex program one, we prove the existence of an optimal randomized stationary policies under reasonable conditions.