4 vokální hlasy (Tenor I, Tenor II, Basso I, Basso II), (Ownership) Provenience: Wendelin Tögel, Klášter minoritů Český Krumlov CZ-CbJVK, and (Version Identification) N. 14 CZ-CbJVK
In this paper we propose a primal-dual path-following interior-point algorithm for semidefinite optimization. The algorithm constructs strictly feasible iterates for a sequence of perturbations of the given problem and its dual problem. Each main step of the algorithm consists of a feasibility step and several centering steps. At each iteration, we use only full-Newton step. Moreover, we use a more natural feasibility step, which targets at the μ+-center. The iteration bound of the algorithm coincides with the currently best iteration bound for semidefinite optimization problems.
Let G1 and G2 be copies of a graph G, and let f : V (G1) → V (G2) be a function. Then a functigraph C(G, f) = (V, E) is a generalization of a permutation graph, where V = V (G1) ∪ V (G2) and E = E(G1) ∪ E(G2) ∪ {uv : u ∈ V (G1), v ∈ V (G2), v = f(u)}. In this paper, we study colorability and planarity of functigraphs.
Leaf-root interaction is a critical factor for plant growth during maturation and activity of roots is maintained by a sufficient supply of photosynthates. To explain photosynthate distribution among organs in field crops, the node unit hypothesis is proposed. One node unit consists of a leaf and an upper adventitous root, as well as the axillary organs and the lower adventitious root, which is adjacent to one node. Using 14C as tracer, the carbon distribution system has been clarified using spring wheat, soybean, tomato, and potato. The interrelationship among organs from the strongest to the weakest is in the following order: (1) within the node unit > (2) between the node unit in the same or adjacent phyllotaxy > (3) in the main root or apical organs, which are adjacent to the node unit. Within the node unit, 14C assimilated in the leaf on the main stem tended to distribute to axillary organs in the same node unit. The 14C assimilated in the leaf of axillary organs tended to distribute within the axillary organs, including adventitious roots in the axillary organ and then translocated to the leaf on the main leaf of the same node unit. In different organs of the node unit in the same or adjacent phyllotaxy, 14C assimilated in the leaf on the main stem was also distributed to the organs (node unit) belonging to the same phyllotaxy in dicotyledons, while in monocotyledons, the effect of phyllotaxy on 14C distribution was not clear. Among roots/apical organs and node unit, 14C assimilated in the upper node unit was distributed to apical organs and 14C assimilated in the lower node unit was distributed to roots. Thus the node unit hypothesis of photosynthate distribution among organs is very important for understanding the high productivity of field crops. and M. Osaki ... [et al.].
We apply the general theory of $\tau $-Corson Compact spaces to remove an unnecessary hypothesis of zero-dimensionality from a theorem on polyadic spaces of tightness $\tau $. In particular, we prove that polyadic spaces of countable tightness are Uniform Eberlein compact spaces.
IsiA is a membrane-bound Chl a-antenna protein synthesized in cyanobacteria under iron deficiency. Since iron deficiency is a common nutrient stress in significant fractions of cyanobacterial habitats, IsiA is likely to be essential for some cyanobacteria. However, the role it plays in cyanobacteria is not fully understood. In this review paper, we summarize the research efforts directed towards characterizing IsiA over the past three decades and attempt to bring all the pieces of the puzzle together to get a more comprehensive understanding of the function of this protein. Moreover, we analyzed the genomes of over 390 cyanobacterial strains available in the JGI/IMG database to assess the distribution of IsiA across the cyanobacterial kingdom. Our study revealed that only 125 such strains have an IsiA homolog, suggesting that the presence of this protein is a niche specific requirement, and cyanobacterial strains that lack IsiA might have developed other mechanisms to survive iron deficiency., H.-Y. S. Chen, A. Bandyopadhyay, H. B. Pakrasi., and Obsahuje bibliografické odkazy
Studies involving comparisons of taxa that vary in their degree of relatedness may allow the distinction of functional and phylogenetic components in cercarial sensory systems. In this study, cercariae of allocreadiids Bunodera Railliet, 1896 and Crepidostomum Braun, 1900, lecithodendriid Allassogonoporus Olivier, 1938 and opecoelid Allopodocotyle Pritchard, 1966 were compared as regards ultrastructure and chaetotaxy of sensory receptors as well as neuromorphology. Cercariae were treated with acetylthiocholine iodide and silver nitrate and some were processed for scanning and transmission electron microscopy. The types of cercarial sensory receptors differed in the presence of a tegumentary sheath, a dome-like base and a tegumentary collar, number of cilia (0, 1, 2 or more), cilium length (short, moderately long or long) and tegumentary collar length (low to moderately low, high or very high). Chaetotaxic patterns were consistent at the family level in all taxa studied. Irregular cholinergic nerve networks were identified. The present study indicates that the major categories of cercarial sensory receptors are nonciliated (including sheathed and subtegumentary types) and ciliated (including uncollared and collared types) receptors. It also allows the distinction of functional and phylogenetic components in the sensory systems of the cercariae studied. Functional components were reflected in the numbers of sensory receptors associated with each nerve region and in the ultrastructure and site-specificity of receptor types. Phylogenetic components included taxon-specific chaetotaxic patterns and receptor types.
To investigate the relationship between early nutritional experience, ontogeny of the small intestinal functions and predisposition to obesity development, the following experimental models of male Sprague-Dawley rats were used: 1) rats in which the quantity of nutrition was manipulated from birth to weaning (day 30) by adjusting the number of pups in the nest to 4 (SL), 10 (NL) and 16 pups (LL) and 2) littermates of SL, NL and LL rats fed either a standard or a hypercaloric diet from days 80 to 135 of age. The overfed SL pups were overweight after day 15 and became permanently obese, whereas the underfed smaller LL pups, due to accelerated growth and enhanced food intake from day 30 to day 35, attained a body fat level that did not differ from normally fed NL rats. Moreover, a significantly increased duodenal and jejunal alkaline phosphatase (AP) activity was found in SL and LL rats and these acquired somatic and intestinal characteristics persisted from weaning throughout life. Eight weeks of high-energy diet feeding elicited a similar pattern of intestinal response in SL and LL rats that was clearly different from NL rats. Despite energy overconsumption in these three groups, both SL and LL rats still displayed enhanced AP activity and showed a significant increase in protein/DNA ratio accompanied with a significant body fat accretion. These results indicate that the postnatally acquired small intestinal changes induced by over- and undernutrition could be involved in the similar predisposition to obesity risk in later life when caloric density of the diet is raised., Š. Možeš, Z. Šefčíková, Ľ. Lenhardt., and Obsahuje bibliografii a bibliografické odkazy