The abstract Perron-Stieltjes integral in the Kurzweil-Henstock sense given via integral sums is used for defining convolutions of Banach space valued functions. Basic facts concerning integration are preseted, the properties of Stieltjes convolutions are studied and applied to obtain resolvents for renewal type Stieltjes convolution equations.
Let Th be a triangulation of a bounded polygonal domain Ω ⊂ R2 , Lh the space of the functions from C(Ω) linear on the triangles from Th and Πh the interpolation operator from C(Ω) to Lh. For a unit vector z and an inner vertex a of Th, we describe the set of vectors of coefficients such that the related linear combinations of the constant derivatives ∂Πh(u)/∂z on the triangles surrounding a are equal to ∂u/∂z(a) for all polynomials u of the total degree less than or equal to two. Then we prove that, generally, the values of the so-called recovery operators approximating the gradient ∇u(a) cannot be expressed as linear combinations of the constant gradients ∇Πh(u) on the triangles surrounding a.
Hankel operators and their symbols, as generalized by V. Pták and P. Vrbová, are considered. The present note provides a parametric labeling of all the Hankel symbols of a given Hankel operator $X$ by means of Schur class functions. The result includes uniqueness criteria and a Schur like formula. As a by-product, a new proof of the existence of Hankel symbols is obtained. The proof is established by associating to the data of the problem a suitable isometry $V$ so that there is a bijective correspondence between the symbols of $X$ and the minimal unitary extensions of $V$.
Closure GMV-algebras are introduced as a commutative generalization of closure MV-algebras, which were studied as a natural generalization of topological Boolean algebras.
Description of multiplication operators generated by a sequence and composition operators induced by a partition on Lorentz sequence spaces l(p, q), 1 < p ≤ ∞, 1 ≤ q ≤ ∞ is presented.
Hradiště Vladař u Žlutic (okr. Karlovy Vary) unikalo až donedávna bližší pozornosti archeologů. Článek shrnuje současný stav našich poznatků o této lokalitě a o jejím zasazení do přírodního prostředí. Zároveň upozorňuje na potenciální význam hradiště v mladším pravěku Čech. Vladař se nedávno stal předmětem detailních průzkumů a sondáží v narušených místech. Z popisu dosavadního postupu výzkumu a základní charakteristiky nálezů (především zlomků keramiky) jsou vyvozeny závěry o osídlení v období Ha a LT. and Vladař hillfort, situated close to the town Žlutice, western Bohemia, has attained only little attention from archaeologists until very recently. This contribution provides a description of the current stage of our knowledge of the site, its environmental setting and possible significance in the Bohemian later prehistory (Bronze Age, Hallstatt and La-Tène periods). Vladař hillfort became a focus site for a currently running research project; its actual progress, basic description of the finds – mainly pottery fragments – and some outline of preliminary results about Ha and LT periods settlement are given.
Ophidascaris wangi sp. n. collected from the king rat snake Elaphe carinata (Günther) (Serpentes: Colubridae) in China is described using both light and scanning electron microscopy. The new species differs from its congeners in the presence of narrow lateral alae originating a short distance posterior to the base of the ventrolateral lips, its relatively long oesophagus (3.57-4.54 mm long, representing 6.6-7.6% of body length), its short spicules (1.89-2.14 mm long, representing 3.9-4.3% of body length), the number and arrangement of caudal papillae (49-57 pairs in total, arranged as follows: 43-51 pairs precloacal, 2 pairs joined paracloacal and 4 pairs postcloacal), the presence of a particular papilliform medioventral, postcloacal ornamentation and the morphology of the eggs and tip of the female tail. In addition, Ophidascaris najae (Gedoelst, 1916), collected from the king cobra Ophiophagus hannah Cantor (Serpentes: Elapidae) in China, is also redescribed. The morphology of the cervical papillae, labial denticles and phasmids of the female is described for the first time.
Ophiotaenia bonneti sp. n. is described from the intestine of the frog Rana vaillanti Brocchi, 1877 (Anura: Ranidae) from San Gerardo, Guanacaste, Costa Rica. The new species is characterized by the testes 100-177 in number, the genital pores situated anteriorly, the osmoregulatory canals overlapping the testis field, the cirrus pouch length as 15-24% of proglottis width, and the uterus with 18-32 ramified diverticula on each side. It differs from the 23 known species of the genus Ophiotaenia La Rue, 1911, parasitic in amphibians, by one to several morphological characters. It differs from O. gracilis Jones, Cheng et Gillespie, 1958, the most morphologically similar species, in the sucker diameter in % of scolex diameter and in the morphology of the eggs - funnel-like depression and embryophore closely investing the oncosphere in O. gracilis. We generally observe a very low mean prevalence of the Proteocephalidea in Neotropical amphibians (about 0.41%-3%), but in the case of some host species, the prevalence can reach up to 25%. We conclude that these cestodes exhibit a strict host specificity of the oioxene type. Ophiotaenia junglensis Srivastava et Capoor, 1980 is considered a species inquirenda. Batrachotaenia hernandezi (Flores-Barroeta, 1955) becomes Ophiotaenia hernandezi (Flores-Barroeta, 1955) comb. n., B. tigrina (Woodland, 1925) becomes O. tigrina (Woodland, 1925) comb. n. and B. ceratophryos (Parodi et Widakowich, 1916) becomes O. ceratophryos (Parodi et Widakowich, 1916) comb. n.