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474602. The maximum genus, matchings and the cycle space of a graph
- Creator:
- Fu, Hung-Lin, Škoviera, Martin, and Tsai, Ming-Chun
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- maximum genus, matching, and cycle space
- Language:
- English
- Description:
- In this paper we determine the maximum genus of a graph by using the matching number of the intersection graph of a basis of its cycle space. Our result is a common generalization of a theorem of Glukhov and a theorem of Nebeský.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474603. The McShane, PU and Henstock integrals of Banach valued functions
- Creator:
- Di Piazza, Luisa and Marraffa, Valeria
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Pettis, McShane, PU and Henstock integrals, variational integrals, and multipliers
- Language:
- English
- Description:
- Some relationships between the vector valued Henstock and McShane integrals are investigated. An integral for vector valued functions, defined by means of partitions of the unity (the PU-integral) is studied. In particular it is shown that a vector valued function is McShane integrable if and only if it is both Pettis and PU-integrable. Convergence theorems for the Henstock variational and the PU integrals are stated. The families of multipliers for the Henstock and the Henstock variational integrals of vector valued functions are characterized.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474604. The mechanism of the emergence of Cotesia kariyai (Hymenoptera: Braconidae) larvae from the host
- Creator:
- Nakamatsu, Yutaka, Tanaka, Toshiharu, and Harvey, Jeffrey A.
- Type:
- article, model:article, and TEXT
- Subject:
- Braconidae, Cotesia kariyai, Noctuidae, Pseudaletia separata, emergence, emergence behavior, haemolymph volume, parasitoid, and anchor
- Language:
- English
- Description:
- At maturity, the endoparasitoid larvae of several subfamilies of the Braconidae have to emerge from inside of the host to pupate. Although the hosts hormonal milieu and the timing of larval parasitoid emergence have been studied, no report has yet focused on the physiological state of the host in connection with the emergence behavior of endoparasitoids. We investigated the mechanism of larval emergence behavior in a gregarious endoparasitoid, Cotesia kariyai. The parasitoid larvae inserted their mandibles into the host cuticle and perforated the integument by moving their head-capsule backwards and forwards. The emerging parasitoid larva must have a physical support (an "anchor") with the terminal appendages in order to exert the necessary pressure to cut the host integument. Morphological observations revealed that each parasitoid larva was enveloped in a capsule just before emerging from their host. Eight and nine day-old parasitoid larvae secreted material around their bodies to form these capsules. This material consisted of acid-glycoproteins which coated the exuvium of the 2nd instar larvae. The haemolymph volume of the parasitised host also decreased in later stages and was dramatically reduced immediatly prior to parasitoid emergence. This final reduction of the host haemolymph volume is the result of absorption by parasitoid larvae. This mechanism allows the parasitoid larvae to create an anchor more easily. The parasitoid larvae could also adhere to each other with the glycoprotein. In addition, these capsules prevent the leaking of host haemolymph through the emergence hole; these holes on the host integument were plugged by the capsules after parasitoid emergence. Although the pressure acquired by the anchor was lost once the head of the parasitoid larvae emerges from the host integument, the parasitoid larvae crawls out of the host cavity using backward pointing spines which enable the parasitoid to grip the capsule and move forward via peristaltic contractions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474605. The metabolism of 5-methylcytosine residues in DNA
- Creator:
- Murín, R., Abdalla, M., Murínová, N., Jozef Hatok, and Dušan Dobrota
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- epigenetika, epigenetics, DNA methylation, DNA demethylation, 5-methylcytosine, 14, and 612
- Language:
- English
- Description:
- The fundamental biochemical processes of 5-methylcytosine (5-mC) synthesis, maintenance, conversion and removal determine the time and spatial pattern of DNA methylation. This has a strong effect on a plethora of physiological aspects of cellular metabolism. While the presence of 5-mC within the promoter region can silence gene expression, its derivative - 5-hydroxymethylcytosine exerts an opposite effect. Dysregulations in the metabolism of 5-mC lead to an altered DNA methylation pattern which is linked with a disrupted epigenome, and are considered to play a significant part in the etiology of several human diseases. A summary of recent knowledge about the molecular processes participating in DNA methylation pattern shaping is provided here., R. Murín, M. Abdalla, N. Murínová, J. Hatok, D. Dobrota., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474606. The meteor complex of P/Encke
- Creator:
- Porubčan, V. and Štohl, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- observations, Taurid meteor complex, and P/Encke
- Language:
- Czech
- Description:
- The Taurid meteor complex associated with P/Encke Is studied on the basis of relevant photographic and radar orblts. Orbltal characteristlcs, radiants and durationa of the postperihelion showers are compared with correspondlng theoretlcal values derived from the observationn of the preperihelion Taurlds, Reality of the proposed assoclatlons of mlnor showers with the Taurld complex and the total duratlon of Its actlvilty are evaluated and discussed. Some of the associated showers the Northern and Southern X Orionids, Northern Piscids and Southern Arietids) are confirmed to be In fact parts of the Taurid shower itself.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474607. The method of infinite ascent applied on $A^4 \pm n B^3 = C^2$
- Creator:
- Jena, Susil Kumar
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- method of infinite ascent and Diophantine equation $A^4 \pm nB^3 = C^2$
- Language:
- English
- Description:
- Each of the Diophantine equations $A^4 \pm nB^3 = C^2$ has an infinite number of integral solutions $(A, B, C)$ for any positive integer $n$. In this paper, we will show how the method of infinite ascent could be applied to generate these solutions. We will investigate the conditions when $A$, $B$ and $C$ are pair-wise co-prime. As a side result of this investigation, we will show a method of generating an infinite number of co-prime integral solutions $(A, B, C)$ of the Diophantine equation $aA^3 + cB^3 = C^2$ for any co-prime integer pair $(a,c)$.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474608. The method of upper and lower solutions for a Lidstone boundary value problem
- Creator:
- Guo, Yanping and Gao, Ying
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- $n$-parameter eigenvalue problem, Lidstone boundary value problem, lower solution, and upper solution
- Language:
- English
- Description:
- In this paper we develop the monotone method in the presence of upper and lower solutions for the $2$nd order Lidstone boundary value problem \[ u^{(2n)}(t)=f(t,u(t),u^{\prime \prime }(t),\dots ,u^{(2(n-1))}(t)),\quad 0<t<1, u^{(2i)}(0)=u^{(2i)}(1)=0,\quad 0\le i\le n-1, \] where $f\:[0,1]\times \mathbb{R}^{n}\rightarrow \mathbb{R}$ is continuous. We obtain sufficient conditions on $f$ to guarantee the existence of solutions between a lower solution and an upper solution for the higher order boundary value problem.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474609. The microspatial distribution of beetles (Coleoptera) on exposed riverine sediments (ERS)
- Creator:
- Bates, Adam J., Sadler, Jon P., Perry, Joe N., and Fowles, Adrian P.
- Type:
- article, model:article, and TEXT
- Subject:
- Carabidae, Elateridae, hydroecology, habitat preference, microdistribution, pitfall trapping, riparian, exposed riverine sediments, river Severn, Spatial Analysis by Distance Indices, and (SADIE)
- Language:
- English
- Description:
- Exposed Riverine Sediments (ERS) are often characterised by a high diversity of microhabitats due to strong lateral gradients in temperature, humidity, inundation frequency and availability of aquatic food resources and to variations in the degree of vegetation cover, sediment size and sorting. This variation, potentially in combination with interspecific competitive interactions, is thought to drive the microspatial distribution of ERS invertebrates. This research investigated the microspatial distribution of six ERS specialist beetles across three discreet patches of ERS. In particular it examined the temporal stability of species distributions, and their spatial association with environmental variability and other species. The research used a grid of 204 modified dry pitfall traps over six sampling periods in which weather conditions and water levels were stable, and used the Spatial Analysis by Distance IndicEs (SADIE) method to test the significance of spatial distributions and associations. Strong and significant microspatial zonation was observed for all species, and with few exceptions these distributions were remarkably stable across the study period. This zonation was mainly associated with elevation and proximity to the water, and several species were consistently spatially associated or disassociated with one another. This suggests that laterally more extensive patches of ERS support more species. Operations that reduce the size of ERS patches, such as channelisation, aggregate extraction and regulation are therefore likely to reduce ERS invertebrate diversity.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474610. The model of D-galactosamine-induced injury of rat hepatocytes in primary culture
- Creator:
- Kučera, Otto
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public