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2716. Development and release of a malacosporean (Myxozoa) from Plumatella repens (Bryozoa: Phylactolaemata)

Creator:
Morris, David John, Morris, Donald Charles, and Adams, Alexandra
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Myxozoa, Tetracapsula, Bryozoa, culture, and Buddenbrockia
Language:
English
Description:
During an experiment to transmit Tetracapsula bryosalmonae Canning, Curry, Feist, Longshaw et Okamura, 1999 to a laboratory-cultured bryozoan, Plumatella repens L. a previously undescribed malacosporean species was noted. This parasite produced sacs of spores in the host that reached 1.2 mm in length. The spores released from the sacs appeared similar in size to the two species of Tetracapsula previously described although slight differences in form were noted. Release of spores from the bryozoans was observed associated with the lophophore of the host. The use of experimental bryozoan cultures for the examination of malacosporeans is described and discussed.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2717. Development and verification of a numerical model for calculation of flow in open channels using the finite volume method

Creator:
Link, Oscar and Donoso, Jeanette
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
hydromechanics, Saint-Venant, finite volume method, discretisation schemes, hydromechanika, metoda konečných objemů, and diskretizační schéma
Language:
Slovak
Description:
The finite volume method is applied for solving the conservative Saint-Venant equations in case of a one-dimensional open channel flow with high temporal and spatial variability. A new shock-capturing discretisation scheme is proposed for computation of flow equations with source terms. The proposed scheme, called hybrid, combines adventages of flux-splitting and flux-difference-splitting schemes. Five benchmark tests are used to verify the hybrid scheme. The tests are: (1) Flow in a rectangular cross-section rough channel, (2) instantaneous dambreak over an horizontal, initially dry bed, (3) undercritical flow over a bump, (4) undercritical flow over a bump with change to supercritical flow, and (5) supercritical flow over a bump with hydraulic jump. The quality of the proposed scheme is evaluated and compared with that of well known flux-splitting and flux-difference-splitting schemes, on the base of the average percentual error. Results show that the hybrid scheme has a good precision for calculation of highly unsteady, varied flow and that the model is able to consider a partially dry bed. The average percentual errors of the computations ranged from 0.0 to 5.4 % for flow depth and from 0.0 to 6.3 % for specific discharge. and Metoda konečných objemů se používá při řešení Saint-Venantových rovnic pro jednorozměrné proudění v otevřeném kanále a při velkých časových a prostorových změnách. V práci je navrženo nové diskretizační schéma schopné zachytit rázové jevy pro řešení tokových rovnic se zdrojovými členy. Navržený postup nazýváme hybridním, neboť kombinuje výhody modelování pomocí dvou schémat, nazývaných fluxsplitting a flux-difference-splitting. Pro ověření hybridního schématu bylo testováno pět různých uspořádání. Byly zkoušeny: 1. proudění v drsném korytě s obdélníkovým průřezem, 2. okamžitý vtok do horizontálního původně suchého koryta, 3. podkritické proudění přes práh, 4. podkritické proudění přes práh s přechodem na nadkritické proudění a 5. nadkritické proudění přes práh s hydraulickým skokem. Kvalita navrženého postupu je vyhodnocena a porovnána s výsledky získanými pomocí známých výše uvedených schémat. Byly vyhodnoceny průměrné chyby v procentech. Výsledky naznačují, že hybridní schéma vykazuje dobrou přesnost při výpočtu neustáleného, proměnlivého proudění, a že tento model je schopen vzít v úvahu částečně suché koryto. Průměrné chyby v procentech se pohybovaly od nuly do 5,4 % pro hloubku a od nuly do 6,3 % pro specifický průtok.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2718. Development of biochemical deformable thoracic model

Creator:
Číhalová, Lenka
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
biomechanical simulation, thoracic model, Kroell test, and injury criterion
Language:
English
Description:
The aim of this study is development of biomechanical model of the thorax by the creation of the new factual model of this part of human’s body through the medium of hexahedral grid. The whole model is based on the Finite element method and it has been generated with respect to the real anatomical human data, since the photographs of Visible Human Project have been used for the determination of the spatial arrangement of individual organs. The material properties and contacts have been implemented into the model for the completion of the spatial arrangement and for the completion of the model. The Kroell test has been applied for the validation of the thoracic model. The thoracic injury criteria can be determined from the results of the Kroell test. These injury criteria play considerable role during the accidents. One of these injury criteria is just chest defíection, which has-been investigated during the Kroell test. The validated model will be utilized for the simulation of the vehicle crash situations and for the observation of motion of thoracic organs during the impact. The created model is of great scientific importance since the model is much closer to the biological reality. and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2719. Development of causal interactions between systolic blood pressure and inter-beat intervals in adolescents

Creator:
Jitka Svačinová, Michal Javorka, Zuzana Nováková, Eva Závodná, Czippelová, B., and Nataša Honzíková
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, kauzalita, autonomní nervový systém, adolescenti, causality, autonomic nervous system, adolescents, conditional entropy, baroreflex, 14, and 612
Language:
English
Description:
Systolic blood pressure (SBP) changes control the cardiac interbeat intervals (IBI) duration via baroreflex. Conversely, SBP is influenced by IBI via non- baroreflex mechanisms. Both causal pathways (feedback - baroreflex and feedforward - non- baroreflex) form a closed loop of the SBP- IBI interaction. The aim of this study was to assess the age -related changes in the IBI - SBP interaction. We have non -invasively recorded resting beat -to- beat SBP and IBI in 335 healthy subjects of different age, ranging from 11 to 23 years. Using a linear autoregressive bivariate model we obtained gain (Gain SBP,IBI, used traditionally as baroreflex sensitivity) and coherence (CohSBP,IBI) of the SBP-IBI interaction and causal gain and coherence in baroreflex (Gain SBP → IBI , Coh SBP → IBI ) and coherence in non- baroreflex (CohIBI→SBP) directions separately. A non -linear approach was used for causal coupling indices evaluation (C SBP → IBI , C IBI → SBP ) quantifying the amount of information transferred between signals. We performed a correlation to age analysis of a ll measures. CohIBI→SBP and CIBI→SBP were higher than CohSBP→IBI and CSBP→IBI, respectively. Gain SBP,IBI increased and Coh SBP → IBI decreased with age. The coupling indices did not correlate with age. We conclude that the feedforward influence dominated at rest. The increase of Gain SBP,IBI with age was not found in the closed loop model. A decrease of Coh SBP → IBI could be related to a change in the cardiovascular control system complexity during maturation., J. Svačinová, M. Javorka, Z. Nováková, E. Závodná, B. Czippelová, N. Honzíková., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2720. Development of chloroplast in dark-grown wheat seedlings irradiated at elevated temperature

Creator:
Singh, A. K. and Singhal, G. S.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
carotenoids, chlorophyll, nucleic acids, photosystem 2, proteins, and Triticum aestivum
Language:
Multiple languages
Description:
Elevated temperature inhibited the accumulation of chlorophyll and photosynthetic proteins, and the development of photochemical activity, however, carotenoids continued to accumulate. Signal transduction pathway involved in protochlorophyllide oxidoreductase was unaffected by elevated temperature of 38°C. Two-dimensional gel electrophoresis of stroma proteins showed similar patterns in the dark-grown seedlings and seedlings irradiated at elevated temperature, although some low molecular mass proteins accumulated at 38°C. In contrast, seedlings irradiated at 25°C showed complex pattern of proteins. Hence the development of chloroplast and its associated functions during irradiation of etiolated seedlings are inhibited by elevated temperature. and A. K. Singh, G. S. Singhal.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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