The key role of the vagus nerves in the reflex control of breathing is generally accepted. Cardiopulmonary vagal receptors and their afferent connection with the medullary respiratory centers secures the proper regulatory feedback. Section of the vagi at the midcervical level interrupts primary vagal reflexes and those due to activation of lung afferents by neuroactive substances. In this context the present review focuses on the reflex contribution of the inferior (nodose) vagal ganglia to the respiratory pattern, considering that this structure contains perikarya of vagal afferent neurons which house neurotransmitters, neuropeptides and neurochemical substances. In experimental animals with removed sensory input from the lungs (midcervical vagotomy) the following evidence was reported. Transient respiratory suppression in the form of apnoea, occuring after systemic injection of serotonin, adenosine triphosphate and anandamide (N-arachidonoyl-ethanolamine-endogenous cannabinoid neurotransmitter), which was abrogated by nodose ganglionectomy. Preserved nodose-NTS connection conditioned respiratory depression affecting the timing component of the breathing pattern evoked by N-6-cyclopentyl-adenosine (CPA) and inhibition of both respiratory constituents induced by NPY. Stimulatory effect of NPY13-36 on tidal volume required nodosal connection. The cardiovascular effects of majority of the tested substances occurred beyond the nodose ganglia (with exclusion of serotonin and anandamide)., K. Kaczyńska, M. Szereda-Przestaszewska., and Obsahuje seznam literatury
Gearboxes and similar machines containing rotating parts are complex systems with complicated structure and couplings. Generally they can be decomposed into more simple subsystems. These subsystems are usually rotating shafts with gears joined
by gear couplings and housing coupled with rotating shafts by bearings. The paper is aimed at the mathematical modelling of gearboxes with spur helical gears considered including their interior rotating shaft system and housing. The used bearing model
respects real number of rolling elements and roller contact forces acting between the journals and the outer housing. The model of a complete gearbox is created using the modal synthesis method. The kinematic transmission errors in gear couplings are viewed as sources of excitation. Vibration and noise analysis of the gearbox housing is performed by means of the created model. Four types of objective functions suitable for optimization from the radiated noise point of view are proposed. The presented methodology is applied to the simple test-gearbox. and Obsahuje seznam literatury
Silicon photomultiplier (SiPM) detectors, also called multipixel photon counters (MPPC), are introduced together with their main characteristics. The focus is given on the timing performance of SiPMs, which is important for the Cherenkov time-of-flight applications, where the SiPMs provide time resolution of the 10 ps order. The time performance is, naturally, influenced by the readout electronic noise. A method for the evaluation of the noise contribution using a Monte Carlo simulation combined with the laboratory measurements is presented and demonstrated on an example of STMicroelectronics NRD09_1 and FBK SiPM-NUV3S SiPMs. The noise contribution to the time resolution depends on the SiPM pulse amplitude A as 1/A. and Článek představuje SiPM detektory, též nazývané MPPC, a jejich základní charakteristiky. Důraz je kladen na využití při měření času, což je důležité např. pro čerenkovské detektory pro měření času průletu, které při využití SiPM dosahují časového rozlišení řádově 10 ps. Přesnost měření času je ovlivněna šumem produkovaným vyčítací elektronikou. Článek představuje metodu pro vyhodnocení vlivu šumu využívající Monte Carlo simulaci v kombinaci s daty naměřenými v laboratoři. Metoda je demonstrována na příkladu dvou SiPM: STMicroelectronics NRD09_1 a FBK SiPM-NUV3S. Obě SiPM vykazují závislost příspěvku šumu k časovému rozlišení na amplitudě SiPM pulzu A ve tvaru 1/A.
This article describes a technique for noise reduction of the differential bearings. Noise is excited by the mechanical looseness of the system and by the vibrations of the engine. The mathematical model enables the optimization of the radial stiffness of the differential bearings. A test rig has been designed for the simulation of the phenomenon outside the vehicle. Analytical software has been created that is capable of classifying the types of noise from the measured data. The optimal solution is tested on the rig at the end, thus proving that the technique works. and Obsahuje seznam literatury
NomVallex 2.0 is a manually annotated valency lexicon of Czech nouns and adjectives, created in the theoretical framework of the Functional Generative Description and based on corpus data (the SYN series of corpora from the Czech National Corpus and the Araneum Bohemicum Maximum corpus). In total, NomVallex is comprised of 1027 lexical units contained in 570 lexemes, covering the following parts-of-speech and derivational categories: deverbal or deadjectival nouns, and deverbal, denominal, deadjectival or primary adjectives. Valency properties of a lexical unit are captured in a valency frame (modeled as a sequence of valency slots, each supplemented with a list of morphemic forms) and documented by corpus examples. In order to make it possible to study the relationship between valency behavior of base words and their derivatives, lexical units of nouns and adjectives in NomVallex are linked to their respective base lexical units (contained either in NomVallex itself or, in case of verbs, in the VALLEX lexicon), linking up to three parts-of-speech (i.e., noun – verb, adjective – verb, noun – adjective, and noun – adjective – verb).
In order to facilitate comparison, this submission also contains abbreviated entries of the base verbs of these nouns and adjectives from the VALLEX lexicon and simplified entries of the covered nouns and adjectives from the PDT-Vallex lexicon.
The NomVallex I. lexicon describes valency of Czech deverbal nouns belonging to three semantic classes, i.e. Communication (dotaz 'question'), Mental Action (plán 'plan') and Psych State (nenávist 'hatred'). It covers both stem-nominals and root-nominals (dotazování se 'asking' and dotaz 'question'). In total, the lexicon includes 505 lexical units in 248 lexemes. Valency properties are captured in the form of valency frames, specifying valency slots and their morphemic forms, and are exemplified by corpus examples.
In order to facilitate comparison, this submission also contains abbreviated entries of the source verbs of these nouns from the Vallex lexicon and simplified entries of the covered nouns from the PDT-Vallex lexicon.