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31582. Quantitative aspects of the fever response elicited by intracerebral injection of endotoxin in the guinea-pig
- Creator:
- Spížková, K. and Štefl, B.
- Type:
- article, model:article, and TEXT
- Subject:
- fever, endotoxin, and indomethacin
- Language:
- English
- Description:
- Fever developing after intracerebral injections of lipopolysaccharide (LPS) to guinea-pigs were monophasic, with only one peak of inner body temperature,slowly developing and longlasting in a dose range 20 to 200 ng of LPS. Latency time was inversely related to the dose of LPS. Indomethacin injected to the third brain ventricle did not abolish fever response.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31583. Quantitative ballistocardiography (Q-BCG) for measurement of cardiovascular dynamics
- Creator:
- Trefný, Z. M., Jiří Svačinka, Otomar Kittnar, Jaroslav Slavíček, Martin Trefný, Filatova, E., Josef A. Tichý, Pavel Smrčka, Stork, M., and Miloslav Loučka
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, srdce, kardiovaskulární fyziologie, heart, cardiovascular physiology, quantitative ballistocardiography, systolic force, minute cardiac force, cardiovascular dynamics, human heart, 14, and 612
- Language:
- English
- Description:
- In the seventies of the past century ballistocardiography had been thought to be obsolete in cardiology for impossibility of objective calibration. In the present work the quantitative ballistocardiography (Q-BCG) for measurement of systolic force (F) and minute cardiac force (MF) in sitting subject was described. The new principle of piezoelectric transducer enabled to register the force caused by the heart and blood movement, which was not measured before. The calibration proved that the action of the force on the transducer was expressed quantitatively without the amplitude-, time-, and phase deformation. The close relationship of skeletal muscle force and F was proved. The F and MF changed under different physiological conditions (age, partial pressure of oxygen, body weight, skeletal muscle force). It was shown that the systolic force (F) and minute cardiac force (MF) are the physiological parameters neurohumorally regulated similarly as the heart rate or systolic volume., Z. M. Trefný ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31584. Quantitative changes in protein, glycogen and fat content in the eggs of the locusts, Locusta migratoria migratorioides and Schistocerca gregaria (Orthoptera), during embryogenesis
- Creator:
- Němec, Václav
- Type:
- article, model:article, and TEXT
- Subject:
- Embryogenesis, protein, glycogen, neutral lipids, sterols, Locusta migratoria, and Schistocerca gregaria
- Language:
- English
- Description:
- Changes in the content of protein, glycogen, neutral lipids and sterols were investigated in locust eggs from oviposition until larval hatching. The content of all of these nutritional reserves was higher in the eggs of S. gregaria because of their larger size, although relative changes in utilization or synthesis of these materials during embryogenesis showed a more or less parallel course. The amount of protein increased progressively during embryogenesis, while glycogen and neutral lipids were successively metabolized or utilized for development of the embryo. There appeared significant relative differences in the way of utilizing energetic reserves during embryogenesis between the two species. This was especially manifested by a larger relative decrease in the content of neutral lipids (mainly triglyceride) in the eggs of S. gregaria. Conversely, the eggs of L. migratoria showed a larger relative utilization of glycogen reserves. The content of steroids was higher in the eggs of S. gregaria during the initial 6 days of embryonic development. Later on, during advanced stages of pharate larval development, the steroids were rapidly utilized and decreased in both species. The described changes in utilization of the main energetic resources were correlated with periods of tissue growth and differentiation and with the cuticulogenesis of the growing embryo.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31585. Quantitative Economic History :
- Creator:
- Fishlow, Albert,
- Type:
- text and studie
- Subject:
- Dějiny Spojených států amerických, ekonomika, dějiny ekonomické, hospodářství, USA, hospodářské dějiny, and světové dějiny 1789-1918
- Language:
- English
- Rights:
- unknown
31586. Quantitative evaluation of body surface potential mapping of heart electrical field in ischaemic heart disease
- Creator:
- Málková, A., Polánková, M., Drška, Z., Valová, D., Jebavý, P., Kallmünzer, B., and Kittnar, O.
- Type:
- article, model:article, and TEXT
- Subject:
- ECG, body surface potential mapping, and ischaemic heart disease
- Language:
- English
- Description:
- Mew possibilities of quantitative evaluation of body surface potential mapping were studied in 78 patients with ischaemic heart disease. Integral maps of the Q wave, QRS and ST-T intervals were plotted and isochronous maps of ventricular activation time and maps of asynchronous potential minima of the Q wave were determined. Minimum and maximum potential values and their time relations were evaluated in the maps. Left ventricular contraction abnormality detected by left ventricular angiography was determined by a point score and expressed as an index of asynergy. The number of coronary artery branches with significant narrowing was assessed and the extent of coronary artery damage was evaluated by an arbitrary defined index. Using quantitative parameters from the maps, multiple stepwise linear regression was performed. The relationship between map parameters and index of asynergy corresponded to multiple correlation coefficient r=0.69 (p=0.01) in the whole group of patients. In the group of patients with left ventricular contraction abnormality the relationship between these parameters was found to be r=0.87 (p=0.01). The relationship between map parameters and the number of coronary artery branches with significant stenosis was r=0.60 (p=0.01) in the group of patients with positive coronary angiography. In the same group of patients the relationship between map parameters and the index evaluating coronary artery damage was equal to r=0.63 (p=0.01). The data obtained from body surface integral maps enable to quantify cardiac ischaemic damage.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
31587. Quantitative response to photoperiod and weak coupling between seasonal morphs and diapause regulation in the Asian comma butterfly, Polygonia c-aureum (Lepidoptera: Nymphalidae)
- Creator:
- Hiroyoshi, Satoshi , Takeda, Makio , Mitsunaga, Takayuki , and Reddy, Gadi V.P.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Lepidoptera, Nymphalidae, Polygonia c-aureum, diapause induction, photoperiodism, ovary, reproduction, and seasonal form
- Language:
- English
- Description:
- Reproduction and wing patterns (shape and colouration) in Polygonia c-aureum L. (Lepidoptera: Nymphalidae) are regulated by both photoperiod and temperature experienced during the immature stages, which result in the development of summer or autumn forms. The critical day length for this seasonal change in form was 13.5L : 10.5D at 21°C and 13L : 11D at 25°C. We investigated the connection between seasonal form and female reproduction. Under a 15L : 9D photoperiod at 21°C, reproductively active summer form butterflies are produced, whereas under an 8L : 16D photoperiod at 21°C autumn form butterflies with a strong tendency to enter diapause were produced. On the other hand, under the critical day lengths at 21 or 25°C, autumn form butterflies developed with a weak tendency to enter diapause. When the adult butterflies were transferred from a critical or a short photoperiod to a long photoperiod shortly after emergence, the former were more likely to terminate diapause than the latter. If individuals are reared throughout their entire life cycle under a short photoperiod at 21°C, all the adults have a strong tendency to enter diapause. These results reveal the quantitative effects of photoperiod on diapause in this butterfly and strongly indicate that the determination of the autumn form and induction and maintenance of diapause are not rigidly coupled, at least under laboratory conditions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31588. Quantitative trading of gold and silver using nonlinear models
- Creator:
- Dunis, Christian L. and Nathani, Anup
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Gold, higher order neural networks, MultiLayer perceptron, nearest neighbours, silver, and trading models
- Language:
- English
- Description:
- The main aim of this paper is to forecast gold and silver daily returns with advanced regression analysis using various linear and non-linear models. ARMA models are used as a linear benchmark for comparison purposes with established non-linear models such as Nearest Neighbours and MultiLayer Perceptron (MLP), and Higher Order Neural Networks (HONN) whose application to financial markets is quite new. All models are assessed using statistical criteria such as correct directional change as well as financial criteria such as risk adjusted return. The main aim is to find which of these models generate the best returns and if nonlinear models can be used for generating excess returns in the precious metals market. This is achieved by implementing a trading simulation where the forecast is translated into a trading signal. Profit statistics are calculated taking into account transaction costs. It is concluded that, for the January 2000-May 2006 period under review, nonlinear models like MLPs and HONNs did outperform the linear ARMA models. In the end, the performance of both MLP and HONN models showed the presence of nonlinearities in the gold and silver prices as it was found that nonlinear models can be effectively used for generating excess returns in these markets.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31589. Quantum ant colony optimization algorithm based on Bloch spherical search
- Creator:
- Li, Panchi and Wang, Haiying
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Ant colony optimization, quantum ant colony optimization, Bloch sphere, and algorithm design
- Language:
- English
- Description:
- In the existing quantum-behaved optimization algorithms, almost all of the individuals are encoded by qubits described on plane unit circle. As qubits contain only a variable parameter, quantum properties have not been fully embodied, which limits the optimization ability rise further. In order to solve this problem, this paper proposes a quantum ant colony optimization algorithm based on Bloch sphere search. In the proposed algorithm, the positions of ants are encoded by qubits described on Bloch sphere. First, the destination to move is determined according to the select probability constructed by the pheromone and heuristic information, then, the rotation axis is established with Pauli matrixes, and the evolution search is realized with the rotation of qubits on Bloch sphere. In order to avoid premature convergence, the mutation is performed with Hadamard gates. Finally, the pheromone and the heuristic information are updated in the new positions of ants. As the optimization process is performed in $n$-dimensional hypercube space $[-1,1]^{n}$, which has nothing to do with the specific issues, hence, the proposed method has good adaptability for a variety of optimization problems. The simulation results show that the proposed algorithm is superior to other quantum-behaved optimization algorithms in both search ability and optimization efficiency.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
31590. Quantum Bochner theorems and incompatible observables
- Creator:
- Hudson, Robin L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Bochner´s Theorem, multiplier-nonnegative- definiteness, Wigner quasidensities, and Pauli matrices
- Language:
- English
- Description:
- A quantum version of Bochner's theorem characterising Fourier transforms of probability measures on locally compact Abelian groups gives a characterisation of the Fourier transforms of Wigner quasi-joint distributions of position and momentum. An analogous quantum Bochner theorem characterises quasi-joint distributions of components of spin. In both cases quantum states in which a true distribution exists are characterised by the intersection of two convex sets. This may be described explicitly in the spin case as the intersection of the Bloch sphere with a regular tetrahedron whose edges touch the sphere.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public