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1353. Direct modeling of the gravitational field using harmonic series

Creator:
Pavel Novák
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, tíhový potenciál Země, topografie, mořská voda, gravitational potential, topography, sea water, Earth Gravitational Model, gravity reduction and stripping, ocean water, spherical harmonic series, 7, and 551
Language:
English
Description:
During the General Assembly of the European Geosciences Union in April 2008, the new Earth Gravitational Model 2008 (EGM08) was released with fully-normalized coefficients in the spherical harmonic expansion of the Earth's gravitational potential complete to degree and order 2159. EGM08 is based on inverse modeling methods that rely on data observed both on the Earth's surface and in space. Forward modeling equations based on Newtonian integrals can be converted into series forms that are compatible with the spherical harmonic description of the geopotential. Namely gravitational potentials of ocean water (fluid masses below the geoid) and topographical masses (solid masses above the geoid) can be formulated and evaluated numerically through spherical harmonic expansions. The potential constituents as well as their radial derivatives can be used for a step known in geodesy and geophysics as gravity field reduction or stripping. Reducing EGM08 for these constituents can help to analyze the internal structure of the Earth (geophysics) as well as to derive the Earth's gravitational field harmonic outside the geoid (geodesy)., Pavel Novák., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1354. Discharge properties of neurons in subdivisions of the medial geniculate body of the guinea pig

Creator:
Kvašňák, E. and Jiří Popelář
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, fyziologie, morčata, physiology, Guinea pigs, discharge pattern, single neuron activity, medial geniculate body, subdivisions, 14, and 612
Language:
English
Description:
The activity of 194 neurons was recorded in three subdivisions of the medial geniculate body (74 neurons in the ventral, 62 in the medial and 44 neurons in the dorsal subdivision, i.e. vMGB, mMGB and dMGB) of guinea pigs anesthetized with ketamine-xylazine. The discharge properties of neurons were evaluated by means of peristimulus time histograms (PSTHs), interval histograms (INTHs) and auto-correlograms (ACGs). In the whole MGB, the most frequent PSTH responses to pure tone stimuli were onset (43 %) or chopper (32 %). The onset responses were mostly present in the vMGB, whereas chopper responses dominated in the dMGB. In the whole MGB Poisson-like and bimodal INTHs were found in 46 % and 40 % of neurons, respectively. The mMGB revealed fewer bimodal and more symmetrical types of INTH. In the whole MGB, 60 % of units were found to have ACGs typical for short bursts (<100 ms), 23 % for long bursts (>100 ms) and 15 % of units fired without bursts. Neurons in the vMGB were characterized by short bursting, whereas those in the mMGB and dMGB expressed more activity in the long bursts. The results demonstrate that the type of information processing in the vMGB, which belongs to the ”primary” auditory system, is different from that in two other subdivisions of the MGB., E. Kvašňák, J. Popelář, J. Syka., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1357. Diskuse k zonaci NP Šumava

Creator:
Pavel Cudlín
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Věda. Všeobecnosti. Základy vědy a kultury. Vědecká práce, Akademie věd České republiky., Komise pro životní prostředí, Zonace NP Šumava (2015 : Praha, Česko), věda a společnost, národní parky, ochrana přírody, semináře, science and society, national parks, nature conservation, seminars, Šumava (pohoří), Šumava Mountains, zonace, zóny národního parku, odborné semináře, 12, and 00
Language:
Czech
Description:
V nejbližší době projedná Poslanecká sněmovna PČR novelu zákona o ochraně přírody, kterou připravilo ministerstvo životního prostředí. Novela mění dosavadní systém zonace národních parků, například tím, že místo stávajících tří navrhuje zóny čtyři. Obzvláště v souvislosti s NP Šumava vzbudila tato novela živou diskusi. Komise pro životní prostředí AV ČR proto uspořádala odborný seminář s cílem nahlédnout otázku zonace NP Šumava z nejrůznějších pohledů: od legislativního přes sociálně-ekonomický, obecně přírodovědecký až po ryze ochranářský. Důležitou součástí úvah o zonaci NP Šumava představovala i fundovaná analýza jejích potenciálních vlivů na obyvatele žijící uvnitř NPŠ či v blízkém okolí. and Pavel Cudlín.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1358. Diskuse o migraci bez emocí a politické korektnosti

Creator:
Jaroslav Pánek
Format:
print, bez média, and svazek
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Věda. Všeobecnosti. Základy vědy a kultury. Vědecká práce, emigrace, konference, emigranti, emigrants, emigration, conferences, 12, and 00
Language:
Czech
Description:
Čeští a němečtí odborníci v oboru historie, sociální geografie, ekonomie, politologie, teologie a orientalistiky promluvili ve veřejné panelové diskusi „Uprchlíci a my: Česká očekávání a německá zkušenost“, kterou za účasti německého velvyslance Arndta Freiherra Freytaga von Loringhovena uspořádala Učená společnost ČR 19. dubna 2016 v budově Akademie věd ČR. Následná rozsáhlá debata prokázala velký zájem veřejnosti o tuto tematiku. Zveřejňujeme úvodní slovo prof. Jaroslava Pánka z Historického ústavu AV ČR v původním znění, které na diskusi muselo být vzhledem k omezenému času značně zkráceno. and Jaroslav Pánek.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

1359. Disodium cromoglycate attenuates hypoxia induced enlargement of end-expiratory lung volume in rats

Creator:
Hana Maxová, Hezinová, A., and Martin Vízek
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, patologická fyziologie, hypoxie, pathopsychology, hypoxia, chronic hypoxia, end-expiratory lung volume, tissue remodeling, mast cells, disodium cromoglycate, 14, and 612
Language:
English
Description:
Mechanism responsible for the en largement of end-expiratory lung volume (EELV) induced by chronic hypoxia remains unclear. The fact that the increase in EELV persists after return to normoxia suggests involvement of morphological changes. Because hypoxia has been also show n to activate lung mast cells, we speculated that th ey could play in the mechanism increasing EELV similar role as in vessel remodeling in hypoxic pulmonary hypertension (HPH). We, therefore, tested an effect of mast cells degranulation blocker disodium cromoglycate (DSCG) on hypoxia induced EELV enlargement. Vent ilatory parameters, EELV and right to left heart weight ratio (RV/LV+S) were measured in male Wistar rats. The experimental group (H+DSCG) was exposed to 3 weeks of normobaric hypoxia and treated with DSCG during the first four days of hypoxia, control group was exposed to hypoxia only (H), two others were kept in normoxia as non-treated (N) and treated (N+DSCG) groups. DSCG treatment significantly attenuated the EELV enlargement (H+DSCG=6.1 ± 0.8; H=9.2 ± 0.9; ml ± SE) together with the increase in minute ventilation (H+DSCG=190 ± 8; H=273 ± 10; ml/min ± SE) and RV/LV+S (H+DSCG=0.39 ± 0.03; H=0.50 ± 0.06)., H. Maxová, A. Hezinová, M. Vízek., and Obsahuje bibliografii a bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

1360. Disordered myocardial Ca2+ homeostasis results in substructural alterations that may promote occurrence of malignant arrhythmias

Creator:
Narcisa Tribulová, Knezl, V., Szeiffova Bačová, B., Egan Beňová, Viczenczova, C., Eva Gonsalvesová, and Ján Slezák
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, fyziologie, morčata, prasata, physiology, Guinea pigs, pigs, Ca2+ overload, heart ultrastructure, malignant arrhythmias, rat, 14, and 612
Language:
English
Description:
We aimed to determine the impact of Ca2+-related disorders induced in intact animal hearts on ultrastructure of the cardiomyocytes prior to occurrence of severe arrhythmias. Three types of acute experiments were performed that are known to be accompanied by disturbances in Ca2+ handling. Langedorffperfused rat or guinea pig hearts subjected to K+-deficient perfusion to induce ventricular fibrillation (VF), burst atrial pacing to induce atrial fibrillation (AF) and open chest pig heart exposed to intramyocardial noradrenaline infusion to induce ventricular tachycardia (VT). Tissue samples for electron microscopic examination were taken during basal condition, prior and during occurrence of malignant arrhythmias. Cardiomyocyte alterations preceding occurrence of arrhythmias consisted of non-uniform sarcomere shortening, disruption of myofilaments and injury of mitochondria that most likely reflected cytosolic Ca2+ disturbances and Ca2+ overload. These disorders were linked with non-uniform pattern of neighboring cardiomyocytes and dissociation of adhesive junctions suggesting defects in cardiac cell-to-cell coupling. Our findings identified heterogeneously distributed high [Ca2+]i-induced subcellular injury of the cardiomyocytes and their junctions as a common feature prior occurrence of VT, VF or AF. In conclusion, there is a link between Ca2+-related disorders in contractility and coupling of the cardiomyocytes pointing out a novel paradigm implicated in development of severe arrhythmias., N. Tribulova, V. Knezl, B. Szeiffova Bacova, T. Egan Benova, C. Viczenczova, E. Gonçalvesova, J. Slezak., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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