The freely diffusible radical, nitric oxide (NO), has been assumed to act as a retrograde signaling molecule that modulates transmitter release. Acetylcholine (ACh) is known to function as a typical neurotransmitter. In the present work we have examined the presence of both transmitters (NO and ACh) and their possible relations in the rabbit spinal cord. In our experiments we have used histochemical methods for the visualization of acetylcholinesterase (AChE) and NADPH diaphorase (NADPH-d) which label neurons that express nitric oxide synthase (NOS). Both histochemical methods were performed separately or together on the same sections of the thoracic spinal cord. NADPH-d positive dark blue stained neurons were seen mostly in superficial and deep layers of the dorsal horn, preganglionic autonomic neurons and pericentral area. The presence of AChE positive amber yellow neurons was confirmed mostly in motoneurons located in the ventral horns and in neurons of the pericentral and intermediate zone. Besides the above mentioned neurons, also double-labeled neurons were found which contained both the yellow and dark blue histochemical product. Their presence was confirmed in the intermediate zone and in the pericentral area. Thus, the co-existence of NADPH-d and AChE occurred in the location of interneurons. Our observations suggest that NO may play a role in the control of cholinergic neuronal activity and that NO can be involved in the modulation of synaptic transmission., D. Kluchová, K. Schmidtová, S. Rybárová, K, Lovásová, M. Pomfy, T. Prosbová, A. Vatľak., and Obsahuje bibliografii
The partial consumption of prey refers to when a predator does not consume all the digestible biomass of an animal it has killed. The frequency of partial consumption of prey by the polyphagous predator Macrolophus pygmaeus (Hemiptera: Miridae) was recorded for different species of prey and prey population structures, in single and mixed prey species patches. All the instars of the aphid, Aphis gossypii, were provided as prey alone or together with Myzus persicae or Macrosiphum euphorbiae. Numbers killed were determined when equal (10 nymphs of each instar, 40 in total) or unequal numbers (higher numbers of young nymphs but again 40 in total) of nymphs were placed on an eggplant leaf in a plastic Petri dish. In each dish a single 5th instar nymph of the predator was introduced and the numbers killed and numbers of partially consumed aphids were recorded after 24h, at 25 ± 1°C. The numbers of A. gossypii killed were higher than those of the other species of prey used. The frequency of partially consumed prey was highest when A. gossypii was offered alone in equal numbers of each instar, followed by when A. gossypii was provided together with M. persicae in unequal numbers of instars (23.6% and 11.2%, of the total mortality, respectively). Killed but not consumed prey was also recorded, at frequencies that reached 10.7% of the total mortality when A. gossypii was provided alone in equal numbers of each instar. For M. persicae and M. euphorbiae, these percentages were significantly lower. The higher frequency of this behaviour when A. gossypii was the prey may be related to its lower nutritional quality for the predator. The effect of prey instar was not significant. These results indicate that in determining the numbers killed by a predator, partially consumed prey may make up a significant part of the total kill and thus should be taken into consideration., Dionyssios Lykouressis, Dionyssios Perdikis, Ioannis Mandarakas., and Obsahuje bibliografii
This paper presents two theorems for designing controllers to achieve directional partial generalized synchronization (PGS) of two independent (chaotic) differential equation systems or two independent (chaotic) discrete systems. Two numerical simulation examples are given to illustrate the effectiveness of the proposed theorems. It can be expected that these theorems provide new tools for understanding and studying PGS phenomena and information encryption.
Let f(t, x) be a vector valued function almost periodic in t uniformly for x, and let mod(f) = L1 ⊕ L2 be its frequency module. We say that an almost periodic solution x(t) of the system x˙ = f(t, x), t ∈ , x ∈ D ⊂ Rn is irregular with respect to L2 (or partially irregular) if (mod(x) + L1) ∩ L2 = {0}. Suppose that f(t, x) = A(t)x + X(t, x), where A(t) is an almost periodic (n × n)-matrix and mod(A) ∩ mod(X) = {0}. We consider the existence problem for almost periodic irregular with respect to mod(A) solutions of such system. This problem is reduced to a similar problem for a system of smaller dimension, and sufficient conditions for existence of such solutions are obtained.
This paper deals with a class of partially observable discounted Markov decision processes defined on Borel state and action spaces, under unbounded one-stage cost. The discount rate is a stochastic process evolving according to a difference equation, which is also assumed to be partially observable. Introducing a suitable control model and filtering processes, we prove the existence of optimal control policies. In addition, we illustrate our results in a class of GI/GI/1 queueing systems where we obtain explicitly the corresponding optimality equation and the filtering process.
We are concerned with a class of GI/GI/1 queueing systems with controlled service rates, in which the waiting times are only observed when they take zero value. Applying a suitable filtering process, we show the existence of optimal control policies under a discounted optimality criterion.
The formation of the phosphorylase ab hybrid and its further transformation into phosphorylase a has been demonstrated in the rat heart after different periods of i.v. isoproterenol administration. Phosphorylase ab hybrid was determined in the presence of AMP and/or caffeine. Only the partially phosphorylated phosphorylase was found in the control rat hearts and its activity was 30 % of the total phosphorylase. The phosphorylase ab hybrid was disclosed particularly after small isoproterenol doses (0.031 -0.062 /rg.kg-1) and at short time interval (15 s) after its administration. Higher isoproterenol doses (0.25-0.5 ¿/g.kg-1) changed the partially phosphorylated phosphorylase to phosphorylase a (58 %) after a longer time interval (40 s), The phosphorylase ab hybrid was revealed even at the maximal rate of stimulation. The formation of the phosphorylase ab hybrid in the rat heart in vivo appears to be of physiological significance. Our results confirmed the earlier suggestion that the -AMP/-f AMP activity ratio reflects the percentage proportion of the phosphorylated subunits of phosphorylase but not of the activated phosphorylase molecules.
This paper is a continuation of [5], where $k$-homogeneous and $k$-set-homogeneous algebras were defined. The definitions are analogous to those introduced by Fraïssé [2] and Droste, Giraudet, Macpherson, Sauer [1] for relational structures. In [5] we found all 2-homogeneous and all 2-set-homogeneous monounary algebras when the homogenity is considered with respect to subalgebras, to connected subalgebras and with respect to connected partial subalgebras, respectively. The results of [3], where all homogeneous monounary algebras were characterized, were applied in [4] for 1-homogeneity. The aim of the present paper is to describe all monounary algebras which are 2-homogeneous and 2-set-homogeneous with respect to partial subalgebras, respectively; we will say that they are partially-2-homogeneous and partially-2-set-homogeneous.
Cieľ: Zámerom výskumnej štúdie bolo zistiť, do akej miery sa podieľajú sestry primárnej zdravotnej starostlivosti v onkologickej prevencii v závislosti od štátnej príslušnosti (pracujúce v Slovenskej republike a vo Veľkej Británii – Wales). Metodika: Realizovaná štúdia mala charakter kauzálno-komparatívneho výskumu, ex-post facto. Výskumnú vzorku tvorilo 165 respondentov (počtom 87 sestier v SR a 78 sestier VB) pracujúcich v ambulantných zariadeniach primárnej zdravotnej starostlivosti. Zber údajov prebiehal v období január – júl 2012. Za hlavnú metódu výskumu sme zvolili exploračnú metódu – neštandardizovaný dotazník, ktorý bol po osobnom súhlase sestry predložený a dobrovoľne vyplnený. Pre štatistickú komparáciu sledovaných skupín sme použili dvojrozmernú induktívnu štatistiku, Studentov dvojvzorkový t-test. Výsledky: Štatistickým spracovaním a analýzou získaných údajov boli zaznamenané signifi kantne významné rozdiely v participácii sestier na onkologickej prevencii medzi dvoma krajinami EÚ. V skupine anglických sestier boli pozorované lepšie skórovacie výsledky oproti slovenským sestrám, najmä vo vedení dokumentácie o prítomných rizikových faktoroch podmieňujúcich onkogenézu, v edukácii pacienta/klienta o škodlivosti identifi kovaného rizikového faktora a vedení jej záznamu, v demonštrácii selfdetekčných techník, v realizácii fyzikálneho vyšetrenia u pacienta s dôrazom na prvotné príznaky a aktívnom pozývaní pacientov k preventívnym prehliadkam, či očkovaniu. Záver: Zistené výsledky poukázali na vyššiu mieru uplatnenia preventívnych činností anglickými sestrami, čo možno vysvetliť oprávnením sestier vykonávať preventívne prehliadky a to aktívnym pozývaním pacientov k jednotlivým skríningovým vyšetreniam podľa národných kritérií(National Institute for Health and Care Excellence Guidelines)zohľadňujúce vek, pohlavie, rizikovosť rodiny, čo môže byť stimulom pre zviditeľnenie a zefektívnenie preventívnej starostlivosti v SR, ktorá bude realizovaná sestrami za uznania ich legitímnych kompetencií všetkými zainteresovanými stranami., Aim: The aim of the research study was to determine the extent to which nurses are involved in primary health care in the cancer prevention, depending on nationality (working in the Slovak Republic and the United Kingdom – Wales). Methods: The realized study was character of causal – comparative research, ex – post facto. The research sample consisted of 165 respondents (number 87 nurses in SR and 78 UK nurses) working in outpatient primary care. The data collection was gathered in the period from January to July 2012. We chose the exploratory research method – non-standardized questionnaire, which was submitted and voluntarily completed with personal consent by nurses. For statistical comparison of observed groups, we used two-dimensional inductive statistics, dualsamples Student’s t-test. Results: The statistical processing and analysis of the data showed a signifi cant correlation between the participation of nurses in cancer prevention and nationality. In a group of British nurses were observed scoring with better results compared in group of Slovak nurses in leading documentation of present risk factors underlying oncogenesis, in the education of patient / client about the harmfulness of the identifi ed risk factor and its recording, in demonstrating the body self examination techniques, in the implementation of physical examination with an emphasis the early signs in a patient and in active inviting patients to preventive examinations or vaccinations. Conclusion: The results showed a higher rate in application of the preventive activities in Brithish nurses, what it can be explained by licensed nurses to perform preventive inspections and by actively inviting patients to each screening examination according to national criteria, taking into account age, gender, risk families (NICE guidelines). These facts may be an incentive for eff ectiveness of preventive care in Slovakia, which will be carried out by nurses for recognition of their legitimate competencies by all stakeholders., Andrea Obročníková, Ľudmila Majerníková, and Literatura