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.
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.
The interaction between dislocation dipolar loops plays an important role in the computation of the dislocation dynamics. The analytical form of the interaction force between two loops derived in the present paper from Kroupa's formula of the stress field generated by a single dipolar loop allows for faster computation.
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
Left atrial (LA) volume (LAV) is used for the selection of patients with atrial fibrillation (AF) to rhythm control strategies. Calculation of LAV from the LA diameters and areas by two-dimensional (2D) echocardiography may result in significant error. Accuracy of atrial volume assessment has never been studied in patients with long-standing persistent AF (LSPAF) and significant atrial remodeling. This study investigated correlation and agreement between 2D echocardiographic (Simpson method) and electroanatomic (CARTO, Biosense Webster) left and right atrial (RA) volumes (LAVECHO vs. LAVCARTO and RAVECHO vs. RAVCARTO) in patients undergoing catheter ablation for LSPAF. The study enrolled 173 consecutive subjects (females: 21 %, age: 59±9 years). There was only modest correlation between LAVECHO (92±31 ml) and LAVCARTO (178±37 ml) (R=0.57), and RAVECHO (71±29 ml) and RAVCARTO (173±34 ml) (R=0.42), respectively. LAVECHO and RAVECHO underestimated LAVCARTO and RAVCARTO with the absolute bias (±1.96 standard deviation) of -85 (-148; -22) ml and -102 (-169; -35) ml, respectively, and with the relative bias of -48 (-75; -21) % and -59 (-88; -30) %, respectively (all P<0.000001 for their mutual difference). Significant confounders of this difference were not identified. In patients with LSPAF, 2D echocardiography significantly underestimated both LA and RA volumes as compared with electroanatomic reference. This disagreement was independent of clinical, echocardiographic and mapping characteristics., L. Škňouřil, Š. Havránek, V. Bulková, M. Dorda, T. Paleček, J. Šimek, Z. Fingrová, A. Linhart, J. Januška, D. Wichterle, M. Fiala., and Obsahuje bibliografii
a1_We hypothesize that hypokalemia-related electrolyte imbalance linked with abnormal elevation of intracellular free Ca2+ concentration can cause metabolic disturbances and subcellular alterations resulting in intercellular uncoupling, which favor the occurrence of malignant arrhythmias. Langendorff-perfused guinea pig heart (n = 44) was subjected to a standard Tyrode solution (2.8 mmol/l K+) followed by a K+-deficient solution (1.4 mmol/l K+). Bipolar ECG of the left atria and ventricle was continuously monitored and the incidence of ventricular fibrillation was evaluated. Myocardial tissue sampling was performed during stabilization, hypokalemia and at the onset of fibrillation. Enzyme activities of succinic dehydrogenase, glycogen phosphorylase and 5-nucleotidase were determined using in situ catalytic histochemistry. The main gap junction protein, connexin-43, was labeled using mouse monoclonal antibody and FITC conjugated goat antimouse antibody. Ultrastructure was examined by transmission electron microscopy. The free Ca2+ concentration was measured by the indo-1 method in ventricular cell cultures exposed to a K+-free medium. The results showed that sustained ventricular fibrillation appeared within 15-30 min of low K+ perfusion. This was preceded by ectopic activity, episodes of bigeminy and tachycardia. Hypokalemia induced moderate reversible and sporadically irreversible subcellular alterations of cardiomyocytes and impairment of intercellular junctions, which were heterogeneously distributed throughout myocardium. Patchy areas with decreased enzyme activities and diminished immunoreactivity of connexin-43 were found. Furthermore, lack of external K+ was accompanied by an increase of intracellular Ca2+. The prevention of Ca2+ overload by either 1 mmol/l Ni2+ (Na+/Ca2+ inhibitor), 2.5 mmol/l verapamil, 10 mmol/l d-sotalol or 10 mmol/l tedisamil was associated with the protection agains fibrillation., a2_The results indicate that hypokalemia induces Ca2+ overload injury and disturbances in intercellular coupling. Dispersion of these changes throughout the myocardium may serve as the basis for microreentry circuits and thus favor fibrillation occurrence., N. Tribulová, M. Manoach, D. Varon, L. Okruhlicová, T. Zinman , A. Shainberg., and Obsahuje bibliografii
Measuring of shape deviances, a surface roughness or a surface defects belongs to newly formed requirements in a serial production, especially in production of precise automotive parts. Methods, which are used so far, usually does not meet such requirements - their measuring capacity is not suitable, they cannot check a whole or at least a significant segment of a surface in a short time, they do not cover all the mentioned measuring parameters in one device, they are highly dependent on vibrations and fluctuation of temperature, etc. All of this can be solved using optical contactless dispersive methods. and Měření tvarových úchylek, drsnosti a často i povrchových defektů patří k novým požadavkům sériové výroby, zejména přesných autodílů. Dosud používané metody tyto požadavky většinou nesplňují - nevyhovují výkonem, neumožňují v krátkém čase oskenovat celou kontrolovanou plochu nebo alespoň její část, nezaručí jedním systémem proměřit uvedené parametry, jsou citlivé na vibrace, kolísání teploty atd. Problém je řešitelný až pomocí bezkontaktních optických disperzních metod.