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792. An evaluation of rolling contact fatigue of metallic materials using acoustic emission method
- Creator:
- Nohál, Libor and Mazal, Pavel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acoustic emission, rolling contact fatigue, defect, bearing, and pitting
- Language:
- English
- Description:
- A major cause of a surface damage of the contact loading machine components (bearings, gears, cams etc.) is the rolling contact fatigue, Various methods of condition monitoring are used to detect damage of these components or specimens in the industry or during testing in laboratories. In the past decades, the acoustic emission technique has been developed into useful condition monitoring method. This paper is focused on the testing of rolling contact fatigue of the metallic materials using acoustic emission method. The methodology of testing, experimenal test-rig and preliminary results, are presented in this paper. It can be concluded, that acoustic emission technique can be applied for more accurate rolling contact fatique evaluation of material. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
793. An evidence for regulatory cross-talk between aryl hydrocarbon receptor and glucocorticoid receptor in HepG2 cells
- Creator:
- Zdeněk Dvořák, Radim Vrzal, Petr Pávek, and Jitka Ulrichová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, biochemie, buněčné signály, membránové receptory, xenobiotika, glukokortikoidy, genetická informace, biochemistry, cell signals, membrane receptors, xenobiotics, glucocorticoids, genetic information, dioxin, transcriptional control, 2, and 577
- Language:
- English
- Description:
- Aryl hydrocarbon receptor (AhR) and glucocorticoid receptor (GR) play crucial role in the regulation of drug metabolizing enzymes and in many essential physiological processes. Cellular signaling by these receptors shares several functional and regulatory features. Here we investigated regulatory cross-talk between these two receptors. Human hepatoma cells (HepG2) were the model of choice. We analyzed the effects of dexamethasone (DEX) and dioxin (TCDD) on i) expression of AhR and GRα mRNAs; ii) levels of AhR and GR proteins; iii) transcriptional activities of AhR and GR in reporter assays; iv) 7-ethoxyresorufin-O-deethylase activity (EROD). We found that both DEX and TCDD affected AhR and GR mRNAs expression, proteins levels and transcriptional activities in HepG2 cells. These effects on cellular signaling by AhR and GR comprised up-/down-regulation of gene expression and ligand-dependent protein degradation. We conclude that interactive regulatory cross-talk between GR and AhR receptors in HepG2 cells defines possible implications in physiology and drug metabolism. Future research should be focused on the investigation of AhR-GR cross-talk in various normal human cells and tissues both in vitro and in vivo., Z. Dvořák, R. Vrzal, P. Pávek, J. Ulrichová., and Obsahuje bibliografii a bibliigrafické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
794. An experimental, non-uremic rabbit model of peritoneal dialysis
- Creator:
- Zunic-Bozinovski, S., Lausevic, Z., Krstic, S., Jovanovic, N., Trbojevic-Stankovic, J., and Stojimirovic, B.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Patologie. Klinická medicína, experimentální medicína, peritoneální dialýza, králík, experimental medicine, peritoneal dialysis, Oryctolagus, experimental model, non-uremic rabbit, 14, and 616
- Language:
- English
- Description:
- Peritoneal dialysis (PD) is a well established method of depuration in uremic patients. Standard dialysis solutions currently in use are not biocompatible with the peritoneal membrane. Studying effects of dialysate on peritoneal membrane in humans is still a challenge. There is no consensus on the ideal experimental model so far. We, therefore, wanted to develop a new experimental non-uremic rabbit model of peritoneal dialysis, which would be practical, easy to conduct, not too costly, and convenient to investigate the long-term effect of dialysis fluids. The study was done on 17 healthy Chinchilla male and female rabbits, anesthetized with Thiopental in a dose of 0.5 mg/kg body mass. A catheter, specially made from Tro-soluset (Troge Medical GMBH, Hamburg, Germany) infusion system, was then surgically inserted and tunneled from animals' abdomen to their neck. The planned experimental procedure was 4 weeks of peritoneal dialysate instillation. The presented non-uremic rabbit model of peritoneal dialysis is relatively inexpensive, does not require sophisticated technology and was well tolerated by the animals. Complications such as peritonitis, dialysis fluid leakage, constipation and catheter obstruction were negligible. This model is reproducible and can be used to analyze the effects of different dialysis solutions on the rabbit peritoneal membrane., S. Zunic-Bozinovski, Z. Lausevic, S. Krstic, N. Jovanovic, J. Trbojevic-Stankovic, B. Stojimirovic., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
795. An ideal biological marker of Alzheimer's disease: dream or reality?
- Creator:
- Daniela Řípová and Anna Strunecká
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, Alzheimerova choroba, bílkoviny, recenze, Alzheimer's disease, proteins, reviews, biological peripheral marker, β-amyloid, 14, and 612
- Language:
- English
- Description:
- Senile dementia of Alzheimer´s type (AD) is commonly characterized as a neurodegenerative disorder, which exhibits gradual changes of consciousness, loss of memory, perception and orientation as well as loss of personality and intellect. AD prevalence increases dramatically with age and is the fourth cause of death in Europe and in the USA. Currently, there are no available biological markers, which gives clinicians no other alternative than to rely upon clinical diagnosis by exclusion. There is no assay of objective ante mortem biochemical phenomena that relate to the pathophysiology of this disease. The pathophysiology of AD is connected with alterations in neurotransmission, plaque formation, cytoskeletal abnormalities and disturbances of calcium homeostasis. The search for a test, which is non-invasive, simple, cheap and user-friendly, should be directed at accessible body fluids. Only abnormalities replicated in large series across different laboratories fulfilling the criteria for a biological marker are likely to be of relevance in diagnosing AD. To date, only the combination of cerebrospinal fluid t and Ab42 most closely approximate an ideal biomarker of Alzheimer´s disease. A short review on the role of biological markers in AD on the basis of the literature, contemporary knowledge and our own recent findings are presented., D. Řípová, A. Strunecká., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
796. An improved classifier and transliterator of hand-written Palmyrene letters to Latin
- Creator:
- Hamplová, Adéla, Franc, David, and Veselý, Arnošt
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- artificial intelligence, classification, historical alphabets, mobilenet, and computer vision
- Language:
- English
- Description:
- This article presents the problem of improving the classifier of handwritten letters from historical alphabets, using letter classification algorithms and transliterating them to Latin. We apply it on Palmyrene alphabet, which is a complex alphabet with letters, some of which are very similar to each other. We created a mobile application for Palmyrene alphabet that is able to transliterate hand-written letters or letters that are given as photograph images. At first, the core of the application was based on MobileNet, but the classification results were not suitable enough. In this article, we suggest an improved, better performing convolutional neural network architecture for hand-written letter classifier used in our mobile application. Our suggested new convolutional neural network architecture shows an improvement in accuracy from 0.6893 to 0.9821 by 142% for hand-written model in comparison with the original MobileNet. Future plans are to improve the photographic model as well.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
797. An improved method for the simultaneous determination of photosynthetic O2 evolution and CO2 consumption in Rhizophora mucronata leaves
- Creator:
- Ulqodry, T. Z., Nose, A., and Zheng, S.-H.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, carbon dioxide consumption, oxygen evolution, photosynthetic performance, 2, and 581
- Language:
- Multiple languages
- Description:
- The photosynthetic gas-exchange has been assessed traditionally either as O2 evolution or CO2 consumption. In this study, we used a liquid-phase O2 electrode combined with CO2 optodes to examine simultaneously photosynthesis in intact leaves of mangrove Rhizophora mucronata. We verified suitable conditions for leaf photosynthetic rates by assessing pH levels and NaHCO3 concentrations and compared these to the gas-exchange method at various PAR levels. The photosynthetic rate in response to pH exhibited a similar pattern both for O2 evolution and CO2 consumption, and higher rates were associated with intermediate pH compared with low and high pH values. The net photosynthetic quotient (PQ) of R. mucronata leaves ranged from 1.04-1.28. The PQ values, which were never lesser than 1, suggested that photorespiration did not occur in R. mucronata leaves under aqueous conditions. The similar maximum photosynthetic rates suggested that all measurements had a high capacity to adjust the photosynthetic apparatus under a light saturation condition. The simultaneous measurements of O2 evolution and CO2 consumption using the Clark oxygen electrode polarographic sensor with the CO2 optode sensor provided a simple, stable, and precise measurement of PQ under aqueous and saturated light conditions., T. Z. Ulqodry, A. Nose, S.-H. Zheng., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
798. An inferentialist account of fictional names
- Creator:
- Lee, Byeong D.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fictional names, inferentialist semantics, the anaphoric theory of reference, Sellars, and Brandom
- Language:
- Slovak
- Description:
- The goal of this paper is to present and defend an inferentialist account of the meaning of fictional names on the basis of Sellars-Brandom’s inferentialist semantics and a Brandomian anaphoric theory of reference. On this inferentialist account, the meaning of a fictional name is constituted by the relevant language norms which provide the correctness conditions for its use. In addition, the Brandomian anaphoric theory of reference allows us to understand reference in terms of anaphoric word-word relations, rather than substantial word-world relations. In this paper I argue that this inferentialist account has many important merits over its rival theories. One important merit is that it explains why we can use fictional names to make true statements, even if they lack bearers. As a consequence, this theory allows us to use fictional names without committing ourselves to an implausible ontology of fictional entities. Another important merit is that it provides a uniform semantic account of fictional names across different types of statements in which fictional names are involved.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
799. An influence of changing the humic acids content on soil water repellency and saturated hydraulic conductivity
- Creator:
- Babejová, Natália
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- water repellency, saturated hydraulic conductivity, humic acids, vodoodpudivosť, nasýtená hydraulická vodivosť, and humínové kyseliny
- Language:
- Slovak
- Description:
- An influence of changing the humic acids content on soil water repellency and saturated hydraulic conductivity was studied on soil samples of Mollic Gleysol from Cilizska Radvan in the Danubian Lowland. Water repellency was measured with the water drop penetration time (WDPT) test on original soil samples and on soil samples with increased humic acids content. Saturated hydraulic conductivity coefficient was measured on the above-mentioned samples with falling head permeameter. From the results of measuring it follows that an increasing of humic acids content in soil resulted in an decreasing of the coefficient of saturated hydraulic conductivity of the soil under study. Original soil was non-water reppelent soil. Already a small increasing of humic acids content in soil (in 17.9 % at original amount) caused that the soil became slightly or strongly water repellent in the average of soil moisture 15-30 %. At soil moisture less than 15 % time of penetration decreased probably as a result of shrinking and cracking of the soil. Water repellency of soil samples from horizon 0 - 5 cm was usually higher than water repellency of soil samples from horizon 5 - 10 cm both in case of humic acids extracted from peat and in case of humic acids extracted from the same soil from Cilizska Radvan. and Na pôdnej vzorke čiernice glejovej (ČA G) (MKSP, 2000) z lokality Čiližská Radvaň v Podunajskej nížině bol skúmaný pomocou testu času vsaku kvapky vody (WDPT test) vplyv zmeny obsahu humínových kyselin na vodoodpudivosť a nasýtenú hydraulickú vodivosť pôdy. Vodoodpudivosť bola meraná na pôvodných pôdnych vzorkách a vzorkách zo zvýšeným obsahom humínových kyselín. Koeficient nasýtenej hydraulickej vodivosti bol meraný na týchto pôdnych vzorkách metódou premenlivého hydraulického sklonu. Z nameraných výsledkov vyplýva, že nárast obsahu humínových kyselín v pôde mal za následok pokles koeficientu nasýtenej hydraulickej vodivosti študovanej pôdy. Už malé zvýšenie obsahu humínových kyselín v pôde (o 17,9 % pôvodnej hodnoty ) spôsobilo, že pôda sa stala slabo až silne vodoodpudivou vo vlhkostnom rozsahu 15-30 %. Pri pôdnej vlhkosti nižšej ako 15 % sa čas vsakovania zmenšil pravdepodobne v dôsledku zmršťovania pôdy a vzniku puklín. Vodoodpudivosť pôdnych vzoriek z horizontu 0 - 5 cm vo väčšine prípadov bola vyššia než vodoodpudivosť pôdnych vzoriek z horizontu 5 - 10 cm aj v prípade pridania humínových kyselín, extrahovaných z rašeliny, aj v prípade pridania humínových kyselín, extrahovaných z tej istej pôdy.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
800. An infrared video detection and categorization system based on machine learning
- Creator:
- Švorc, David, Tichý, Tomáš, and Růžička, Miroslav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- convolution neural network, Haar cascade algorithm, thermal classification, and detection and classification system
- Language:
- English
- Description:
- The main aim of this paper is to present a new possibility for detection and recognition of different categories of electric and conventional (equipped with combustion engine) vehicles. These possibilities are provided by use of thermal and visual video cameras and two methods of machine learning. The used methods are Haar cascade classifier and convolutional neural network (CNN). The thermal images, obtained through an infrared thermography camera, were used for the training database. The thermal cameras can complement or substitute visible spectrum of video cameras and other conventional sensors and provide detailed recognition and classification data needed for vehicle type recognition. The first listed method was used as an object detector and serves for the localization of the vehicle on the road without any further classification. The second method was trained for vehicle recognition on the thermal image database and classifies a localized object according to one of the defined categories. The results confirmed that it is possible to use infrared thermography for vehicle drive categorization according to the thermal features of vehicle exteriors together with methods of machine learning for vehicle type recognition.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public