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10032. The Sudetic group of Hieracium subgen. Pilosella from the Krkonoše Mts: a synthetic view
- Creator:
- Krahulec , František, Krahulcová , Anna, Fehrer , Judith, Bräutigam , Siegfried, Plačková, Ivana, and Chrtek , Jindřich
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Asteraceae, breeding systems, chloroplast haplotypes, chromosome numbers, Czech Republic, Hieracium subgen. Pilosella, isozyme phenotypes, Krkonoše Mts, and residual sexuality
- Language:
- English
- Description:
- The present paper summarizes the results of research of Hieracium subgen. Pilosella done by using different methods. The apomictic complex of Hieracium subgen. Pilosella found in the Krkonoše Mts, consists of the following basic species: H. lactucella (2x, sexual), H. onegense (2x, sexual), H. pilosella (4x, sexual), H. caespitosum (4x, apomictic) and H. aurantiacum (4x and 5x, apomictic). These species are considered to be the parents of a further set of mostly apomictic hybridogenous types. The ploidy level, breeding system, isozyme phenotypes, chloroplast haplotypes and geographic distribution of this whole complex was analysed. The different hybridogenous types have different frequencies in the field and differ in the frequency of isozyme phenotypes (a conservative estimate of the number of genotypes). Most have uniform chloroplast haplotypes, but some haplotypes could have originated from reciprocal crosses. The comparison of chloroplast haplotypes suggests that apomictic species were not only pollen donors, but also contributed seed and gave rise to several hybridogenous types, illustrating the importance of the residual sexuality of apomicts in this group. H. pilosella is a central species in this group and is connected with other parental species, H. floribundum, H. lactucella and H. aurantiacum by a set of hybridogenous species that have a similar genetic structure. Some of the distinct hybridogenous types within the complex are of multiple origin. In contrast, crosses between the same parental types may generate diverse progenies, which can often be classified as distinct taxa. All taxa recorded in the past are surveyed and discussed with respect to present knowledge. We suggest that the taxonomy and origin of particular entities of this and other such complexes is best resolved using information from morphological, genetical, cytological and ecological studies.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10033. The Sudetic Marginal Fault: a young morphophotectonic feature at the NE margin of the Bohemian Massif, Central Europe
- Creator:
- Badura, Janusz, Zuchiewicz, Witold, Štěpančiková, Petra, Przybylski, Bogusław, Kontny, Bernard, and Cacoń, Stefan
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, Polsko jihozápadní, Čechy severovýchodní (Česko), Poland, Bohemia, Northeastern (Czechia), morphotectonics, digital elevation models, drainage basin parameters, Sude tic Marginal Fault, 7, and 551
- Language:
- English
- Description:
- We analysed a nearly 133-km-long portion of the Sudetic Marginal Fault (SMF) in Poland (99.7 km) and the Czech Republic (33.8 km), comprised between Złotoryja in the NW and Jesenik in the SE. The fault trace has been subdivided into fifteen segments showing different orientation (N29°W to N56°W, and even N111°W SE of Złoty Stok), geological setting, length (8.8-22.9 km in Poland and 1.4-7.5 km in the Czech Republic), and height of the fault- and fault-line scarps (5-75 m to 200-360 m). Orientation of the entire fault trace approaches N41° W, and the mountain front sinuosity amounts to 1.051. Individual fault segments bear a flight of two to five tiers of triangular facets, showing differentiated state of preservation and degree of erosional remodelling. The highest triangular facets are confined to Rychlebské (Złote) and Sowie Mts. This tiering points to at least five episodes of uplift of the SMF footwall, starting shortly after 31 Ma, i.e. after basalts of the Sichów Hills area were displaced by the fault, and most probably postdating 7-5 Ma time interval, during which rapid cooling and exhumation of the Sowie Góry Mts. massif took place. Morphometric parameters of 244 small catchment areas of streams that dissect the fault scarp include, i.a. elongation, relief, and average slope of individual catchment areas, together with values of the valley flo or width to valley height ratios. These figures point to moderate tectonic activity of the SMF and allow us to conclude about Quaternary uplift, particularly important in the Sowie and Rychlebské (Złote) segments., Janusz Badura, Witold Zuchiewicz, Petra Štěpančiková, Bogusław Przybylski, Bernard Kontny and Stefan Cacoń., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10034. The sum-product algorithm: algebraic independence and computational aspects
- Creator:
- Malvestuto, Francesco M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- sum-product algorithm, distributive law, acyclic set system, and junction tree
- Language:
- English
- Description:
- The sum-product algorithm is a well-known procedure for marginalizing an "acyclic'' product function whose range is the ground set of a commutative semiring. The algorithm is general enough to include as special cases several classical algorithms developed in information theory and probability theory. We present four results. First, using the sum-product algorithm we show that the variable sets involved in an acyclic factorization satisfy a relation that is a natural generalization of probability-theoretic independence. Second, we show that for the Boolean semiring the sum-product algorithm reduces to a classical algorithm of database theory. Third, we present some methods to reduce the amount of computation required by the sum-product algorithm. Fourth, we show that with a slight modification the sum-product algorithm can be used to evaluate a general sum-product expression.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10035. The Surrealist movement in Egypt in the 1930s and the 1940s
- Creator:
- Beránek, Ondřej
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Egypt and Surealist movement
- Language:
- English
- Description:
- The purpose of this aer is to define the nature, history, and scope of the Surealist movement in Egypt in the 1930s and the 1940s and its influence on contemporary Egyptian art. It is also desigend to provide a clear, accessible, and broad background on a diverse group of mainstream and lesser-known innovativde Arabic artists while showing that Surrealism is not a phenomenon unique to Europe. In addition to dealing with the general state of the Egyptian art scene in the 1930s, the aarticle covers the genesis of the Egyptian Surrealis group Art and Liberty and its exhibitions, political activities and two main members, Georges Hénein and Ramsīs Yūnān.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10036. The suspended magnetic separator with large blocks from NdFeB magnets and its long term technological tests
- Creator:
- Žežulka, Václav and Pavel Straka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, magnetické obvody, magnetic circuits, technological innovation, magnetic separation, magnetic separators, permanent NdFeB magnets, 7, and 551
- Language:
- English
- Description:
- The article presents a separator whose magnetic circuit is comprised of large blocks from permanent NdFeB magnets and the knowledge gained from its assembly. In the separation zone of this separator, significantly higher values of magnetic induction were reached in comparison with a similar circuit with ferrite magnets. The results of the long-term comparative technological tests are provided of this separator when used in an industrial plant for the separation of undesirable ferromagnetic admixtures and objects (tramp iron) from raw materials for tile production. Throughout these tests, the fundamental influence of the value of magnetic induction in the separation zone on the amount of the captured magnetic fraction was confirmed and high efficiency of the new separator proven., Václav Žežulka and Pavel Straka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10037. The symmetric Choquet integral with respect to Riesz-space-valued capacities
- Creator:
- Boccuto, Antonio and Riečan, Beloslav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Riesz spaces, capacities, integration, symmetric Choquet integral, and monotone and dominated convergence theorems
- Language:
- English
- Description:
- A definition of “Šipoš integral” is given, similarly to [3],[5],[10], for real-valued functions and with respect to Dedekind complete Riesz-space-valued “capacities”. A comparison of Choquet and Šipoš-type integrals is given, and some fundamental properties and some convergence theorems for the Šipoš integral are proved.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10038. The symmetry reduction of variational integrals
- Creator:
- Tryhuk, Václav and Chrastinová, Veronika
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Routh reduction, Lagrange variational problem, Poincaré-Cartan form, diffiety, standard basis, controllability, and variation
- Language:
- English
- Description:
- The Routh reduction of cyclic variables in the Lagrange function and the Jacobi-Maupertuis principle of constant energy systems are generalized. The article deals with one-dimensional variational integral subject to differential constraints, the Lagrange variational problem, that admits the Lie group of symmetries. Reduction to the orbit space is investigated in the absolute sense relieved of all accidental structures. In particular, the widest possible coordinate-free approach to the underdetermined systems of ordinary differential equations, Poincaré-Cartan forms, variations and extremals is involved for the preparation of the main task. The self-contained exposition differs from the common actual theories and rests only on the most fundamental tools of classical mathematical analysis, however, they are applied in infinite-dimensional spaces. The article may be of a certain interest for nonspecialists since all concepts of the calculus of variations undergo a deep reconstruction.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10039. The symmetry reduction of variational integrals, complement
- Creator:
- Chrastinová, Veronika and Tryhuk, Václav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Lagrange variational problem, Poincaré-Cartan form, and symmetry reduction
- Language:
- English
- Description:
- Some open problems appearing in the primary article on the symmetry reduction are solved. A new and quite simple coordinate-free definition of Poincaré-Cartan forms and the substance of divergence symmetries (quasisymmetries) are clarified. The unbeliavable uniqueness and therefore the global existence of Poincaré-Cartan forms without any uncertain multipliers for the Lagrange variational problems are worth extra mentioning.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10040. The symplectic Gram-Schmidt theorem and fundamental geometries for $\mathcal A$-modules
- Creator:
- Ntumba, Patrice P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- symplectic $\mathcal A$-modules, symplectic basis, orthosymmetric $\mathcal {A}$-bilinear forms, orthogonal/symplectic geometry, and strict integral domain algebra sheaf
- Language:
- English
- Description:
- Like the classical Gram-Schmidt theorem for symplectic vector spaces, the sheaf-theoretic version (in which the coefficient algebra sheaf $\mathcal A$ is appropriately chosen) shows that symplectic $\mathcal A$-morphisms on free $\mathcal A$-modules of finite rank, defined on a topological space $X$, induce canonical bases (Theorem 1.1), called symplectic bases. Moreover (Theorem 2.1), if $(\mathcal {E}, \phi )$ is an $\mathcal A$-module (with respect to a $\mathbb C$-algebra sheaf $\mathcal A$ without zero divisors) equipped with an orthosymmetric $\mathcal A$-morphism, we show, like in the classical situation, that “componentwise” $\phi $ is either symmetric (the (local) geometry is orthogonal) or skew-symmetric (the (local) geometry is symplectic). Theorem 2.1 reduces to the classical case for any free $\mathcal A$-module of finite rank.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public