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15732. Codimension 1 subvarieties $\scr M\sb g$ and real gonality of real curves
- Creator:
- Ballico, Edoardo
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- moduli space of curves, gonality, real curves, Brill-Noether theory, real algebraic curves, and real Riemann surfaces
- Language:
- English
- Description:
- Let ${\mathcal{M}}_g$ be the moduli space of smooth complex projective curves of genus $g$. Here we prove that the subset of ${\mathcal{M}}_g$ formed by all curves for which some Brill-Noether locus has dimension larger than the expected one has codimension at least two in ${\mathcal{M}}_g$. As an application we show that if $X \in {\mathcal{M}}_g$ is defined over ${\mathbb {R}}$, then there exists a low degree pencil $u\: X \rightarrow {\mathbb {P}}^1$ defined over ${\mathbb {R}}$.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15733. Coding of communication calls in the subcortical and cortical structures of the auditory system
- Creator:
- Daniel Šuta, Jiří Popelář, and Josef Syka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, neurofyziologie, neurovědy, sluch, neurophysiology, neuroscientists, hearing, vocalization, guinea pig, inferior colliculus, medial geniculate body, auditory cortex, 14, and 612
- Language:
- English
- Description:
- The processing of species-specific communication signals in the auditory system represents an important aspect of animal behavior and is crucial for its social interactions, reproduction, and survival. In this article the neuronal mechanisms underlying the processing of communication signals in the higher centers of the auditory system - inferior colliculus (IC), medial geniculate body (MGB) and auditory cortex (AC) - are reviewed, with particular attention to the guinea pig. The selectivity of neuronal responses for individual calls in these auditory centers in the guinea pig is usually low - most neurons respond to calls as well as to artificial sounds; the coding of complex sounds in the central auditory nuclei is apparently based on the representation of temporal and spectral features of acoustical stimuli in neural networks. Neuronal response patterns in the IC reliably match the sound envelope for calls characterized by one or more short impulses, but do not exactly fit the envelope for long calls. Also, the main spectral peaks are represented by neuronal firing rates in the IC. In comparison to the IC, response patterns in the MGB and AC demonstrate a less precise representation of the sound envelope, especially in the case of longer calls. The spectral representation is worse in the case of low-frequency calls, but not in the case of broad-band ca lls. The emotional content of the call may influence neuronal responses in the auditory pathway, which can be demonstrated by stimulation with time-reversed calls or by measurements performed under different levels of anesthesia. The investigation of the principles of the neural coding of species-specific vocalizations offers some keys for understanding the neural mechanisms underlying human speech perception., D. Šuta, J. Popelář, J. Syka., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15734. Coefficient inequality for a function whose derivative has a positive real part of order α
- Creator:
- Krishna, Deekonda Vamshee and Ramreddy, Thoutreddy
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- analytic function, upper bound, second Hankel functional, positive real function, and Toeplitz determinant
- Language:
- English
- Description:
- The objective of this paper is to obtain sharp upper bound for the function f for the second Hankel determinant |a2a4 − a 2 3 |, when it belongs to the class of functions whose derivative has a positive real part of order α (0 ≤ α < 1), denoted by RT (α). Further, an upper bound for the inverse function of f for the nonlinear functional (also called the second Hankel functional), denoted by |t2t4 − t 2 3 |, was determined when it belongs to the same class of functions, using Toeplitz determinants.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15735. Coefficient multipliers on spaces of vector-valued entire Dirichlet series
- Creator:
- Akanksha, Sharma and Srivastava, Girja S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- vector-valued Dirichlet series, analytic function, entire function, dual space, and norm
- Language:
- English
- Description:
- The spaces of entire functions represented by Dirichlet series have been studied by Hussein and Kamthan and others. In the present paper we consider the space X of all entire functions defined by vector-valued Dirichlet series and study the properties of a sequence space which is defined using the type of an entire function represented by vectorvalued Dirichlet series. The main result concerns with obtaining the nature of the dual space of this sequence space and coefficient multipliers for some classes of vector-valued Dirichlet series.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15736. COELUM. SUPRA COELOS EXALTATUM AB INITIO ET ANTE SAECULA CREATUM ...
- Creator:
- Andris, Antonín and Tybely, Václav Jan
- Publisher:
- Václav Jan Tybely
- Format:
- print and [6] listů ; 4°
- Type:
- model:monograph and TEXT
- Subject:
- Staré tisky, Náboženství, Panna, Marie, Bratrstvo pod titulem Nanebevzetí Panny Marie u jezuitské koleje (Jičín, Česko), mariologie, náboženská bratrstva, homiletika, 27-312.47, 27-786, 27-475.2, 12, 5, 094, and 2
- Language:
- Czech and Latin
- Description:
- K18204
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15737. Coenological and habitat affinities of Cobitis elongatoides, Sabanejewia balcanica and Misgurnus fossilis in Slovakia
- Creator:
- Pekárik, Ladislav, Koščo, Ján, Košuthová, Lenka, and Košuth, Peter
- Type:
- article and TEXT
- Subject:
- Cobitidae, loaches, habitat preferences, species assemblage, and ecology
- Language:
- English
- Description:
- Three species of the Eurasian family Cobitidae are distributed in Slovakia. In the present paper, we describe the coenological affinity of Cobitis elongatoides, Sabanejewia balcanica and Misgurnus fossilis in two distinct zoogeographical regions, Slovak Tisza and Danube basins and discuss possible differences of their biotop affinity and habitat preferences. The occurrence of S. balcanica is restricted to primary biotopes with harder substratum particles. Typical species assemblages for the rheophilic C. elongatoides are eurytopic and limnophilous species. C. elongatoides is mostly distributed in primary biotopes, such as rivers and channels. It also occurs in secondary biotopes (drainage canal or pit). M. fossilis is distributed mostly in the secondary biotopes, but it is also found in the primary biotopes. Both species prefer fine substratum, but spatial distribution of the two species is different. C. elongatoides prefers harder substratum of sandy particles mixed with mud or detritus and living vegetation, whereas M. fossilis prefers muddy substratum mixed with detritus and dead vegetation.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
15738. Coenzyme Q10 ameliorates cadmium induced reproductive toxicity in male rats
- Creator:
- Saha, R., Roychoudhury, S., Kumar Kar, K. , Varghese, A. C. , Nandi, P. , Sharma, G. D., Formicki, G., Slama, P., and Kolesarova, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- rat, sperm, oxidative stress, DNA damage, and Cadmium
- Language:
- English
- Description:
- This study aimed at investigating the protective role of CoQ10 against cadmium (Cd)-induced reproductive toxicity in male rats. Adult male Wistar rats were exposed to an acute dose of Cd (25 mg/kg bwt; Cd group), Cd+CoQ10 (25 mg/kg bwt Cd+10 mg CoQ10; Cd-Q10 group) and distilled water (control) in vivo for 15 consecutive days and semen quality was assessed. A significant reduction was noted in sperm concentration, progressive motility, morphology and DNA integrity in both Cdand Cd-Q10 groups in comparison to control indicating Cd-induced testicular lipid per oxidation (LPO) and decline in indigenous antioxidant defense system as measured by total antioxidant capacity (TAC) (p<0.05). However, simultaneous co-administration of CoQ10 along with Cd (Cd-Q10 group) was able to improve sperm concentration, motility, progressive motility, morphology, DNA integrity, and testicular TAC as well as lower LPO compared to Cd group (p<0.05). Results indicate that used dose of CoQ10 is capable of moderately ameliorating reproductive toxicity of Cd by improving semen quality and reducing testicular oxidative stress.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15739. Coenzyme Q10 effects in neurological diseases
- Creator:
- Rauchová, Hana
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- idebenone, MitoQ, migraine, Parkinson´s disease, Alzheimer´s disease, multiple sclerosis, and hypertension
- Language:
- English
- Description:
- Coenzyme Q10 (CoQ10), a lipophilic substituted benzoquinone, is present in animal and plant cells. It is endogenously synthetized in every cell and involved in a variety of cellular processes. CoQ10 is an obligatory component of the respiratory chain in inner mitochondrial membrane. In addition, the presence of CoQ10 in all cellular membranes and in blood. It is the only endogenous lipid antioxidant. Moreover, it is an essential factor for uncoupling protein and controls the permeability transition pore in mitochondria. It also participates in extramitochondrial electron transport and controls membrane physicochemical properties. CoQ10 effects on gene expression might affect the overall metabolism. Primary changes in the energetic and antioxidant functions can explain its remedial effects. CoQ10 supplementation is safe and well-tolerated, even at high doses. CoQ10 does not cause any serious adverse effects in humans or experimental animals. New preparations of CoQ10 that are less hydrophobic and structural derivatives, like idebenone and MitoQ, are being developed to increase absorption and tissue distribution. The review aims to summarize clinical and experimental effects of CoQ10 supplementations in some neurological diseases such as migraine, Parkinson´s disease, Huntington´s disease, Alzheimer´s disease, amyotrophic lateral sclerosis, Friedreich´s ataxia or multiple sclerosis. Cardiovascular hypertension was included because of its central mechanisms controlling blood pressure in the brainstem rostral ventrolateral medulla and hypothalamic paraventricular nucleus. In conclusion, it seems reasonable to recommend CoQ10 as adjunct to conventional therapy in some cases. However, sometimes CoQ10 supplementations are more efficient in animal models of diseases than in human patients (e.g. Parkinson´s disease) or rather vague (e.g. Friedreich´s ataxia or amyotrophic lateral sclerosis).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15740. Coexistence of small and large amplitude limit cycles of polynomial differential systems of degree four
- Creator:
- Sáez, Eduardo, Stange, Eduardo, and Szántó, Iván
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- stability, limit cycle, center, and bifurcation
- Language:
- English
- Description:
- A class of degree four differential systems that have an invariant conic $ x^2+Cy^2=1$, $C\in {\mathbb{R}}$, is examined. We show the coexistence of small amplitude limit cycles, large amplitude limit cycles, and invariant algebraic curves under perturbations of the coefficients of the systems.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public