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We present a case report of a patient with acute upper and lower limb ischemia due to paradoxical embolism. A 67-year old woman without history of venous thromboembolism suffered dislocated patellar fracture requiring surgery in November 2017. Two months after surgery she presented to the emergency room with bilateral pulmonary embolism, occlusion of the left subclavian artery, left common femoral artery and superior mesenteric artery. Transesophageal echocardiography detected patent foramen ovale. Vascular surgeon decided against embolectomy, interventional radiologist against pharmacomechanical thrombolysis due to the extent of the occlusions. Systemic thrombolysis (alteplase) was administered successfully with resolution of the emboli in the left subclavian artery, left common femoral artery and superior mesenteric artery.

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A case of fibrocartilaginous embolization in 24-year-old female as a rare cause of spinal cord infarction is presented. It manifests as infarction syndrome with rapid progression of clinical signs - acute onset of quadriparesis and respiratory insufficiency. Among imaging studies MRI is the most accurate as it readily capable of detection of myelopathy and acute intervertebral disc lesion. Other laboratory tests and imaging modalities are usually normal. The final diagnosis is made by exclusion.

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Graphene field effect transistors are becoming an integral part of advanced devices. Hence, the advanced strategies for both characterization and tuning of graphene properties are required. Here we show that the X-ray irradiation at the zero applied gate voltage causes very strong negative doping of graphene, which is explained by X-ray radiation induced charging of defects in the gate dielectric. The induced charge can be neutralized and compensated if the graphene device is irradiated by X-rays at a negative gate voltage. Here the charge neutrality point shifts back to zero voltage. The observed phenomenon has strong implications for interpretation of X-ray based measurements of graphene devices as it renders them to significantly altered state. Our results also form a basis for remote X-ray tuning of graphene transport properties and X-ray sensors comprising the graphene/oxide interface as an active layer.

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This article deals with the analysis of the relationship between the pull-off force measured by atomic force microscopy and the dimensions of water bridge condensed between a hydrophilic silicon oxide tip and a silicon oxide surface under ambient conditions. Our experiments have shown that the pull-off force increases linearly with the radius of the tip and nonmonotonically with the relative humidity (RH). The latter dependence generally consists of an initial constant part changing to a convex-concave-like increase of the pull-off force and finally followed by a concave-like decrease of this force. The reproducibility tests have demonstrated that the precision limits have to be taken into account for comparing these measurements carried out under atmospheric conditions. The results were fitted by a classical thermodynamic model based on water-bridge envelope calculations using the numerical solution of the Kelvin equation in the form of axisymmetric differential equations and consequent calculation of adhesive forces. To describe the measured data more precisely, a decrease of the water surface tension for low RH was incorporated into the calculation. Such a decrease can be expected as a consequence of the high surface curvature in the nanometer-sized water bridge between the tip and the surface.

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OBJECTIVES: This study to assess the environmental pollution status in streams (Loutecky, Spicak, Olsina, Trebovicky, Polecnicky and Luzny) from the Boletice area. DESIGN: Were determined of some metal (Hg, Pb, Cd) concentrations in the muscle and correlations among selected metals as well as standard length and total weight in brown trouth - Salmo trutta morpha fario. RESULTS: The contents of the analyzed metals in muscles were Hg 0.19-0.72, Pb 0.01-0.6 and Cd 0.020-0.083 mg/kg wet weight basis and these concentrations did not exceed the limits admissible in the Czech Republic. CONCLUSIONS: The Czech republic permissible limit for Hg (0.5 mg/kg to omnivors, 1 mg/kg to predators), Pb (0.3 mg/kg) and Cd (0.05 mg/kg) defined in the Codex Alimentarius for safe human consumption exceeded in 6%, 3%, and 0% of analyzed samples for Hg, Pb and Cd respectively. On an average, the order of metal concentrations in the fish muscle was: Hg>Pb>Cd.

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OBJECTIVES: The monitoring survey to assess the environmental pollution status of the river Morava--was carried out in 2014. DESIGN: This study presents the concentrations of heavy metals (Hg, Cr, Zn, Pb and Cd) in the water, sediment and muscle tissue of fish from the middle and lower reaches of the Morava river basin (Becva, Drevnice, Haná, Kyjovka and Morava rivers), in the Czech Republic. Atomic absorption spectrometry (AAS) was used for the analysis of toxic metals. European chub (Squalius cephalus) was chosen as a reference fish species for the comparison of monitored localities. RESULTS: Results showed a positive significant correlation between concentration of Hg, Pb, Cd, Cr and Zn in muscles and age of fishes (p<0.05). The contents of the analyzed metals in European chub muscles were low Hg 0.049-0.402, Pb 0.005-0.035, Cd 0.006-0.026, Cr 0.016-0.042 and Zn 5.59-64.31 mg.kg(-1) wet weight basis and did not exceed the values of limits admissible in the Czech Republic. CONCLUSIONS: The contents of the analyzed metals in European chub muscles were low at monitoring sites and did not exceed the values of limits admissible in the Czech Republic.

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Synthesis of graphene by chemical vapor deposition is a promising route for manufacturing large-scale high-quality graphene for electronic applications. The quality of the employed substrates plays a crucial role, since the surface roughness and defects alter the graphene growth and cause difficulties in the subsequent graphene transfer. Here, we report on ultrasmooth high-purity copper foils prepared by sputter deposition of Cu thin film on a SiO2/Si template, and the subsequent peeling off of the metallic layer from the template. The surface displays a low level of oxidation and contamination, and the roughness of the foil surface is generally defined by the template, and was below 0.6 nm even on a large scale. The roughness and grain size increase occurred during both the annealing of the foils, and catalytic growth of graphene from methane (≈1000 °C), but on the large scale still remained far below the roughness typical for commercial foils. The micro-Raman spectroscopy and transport measurements proved the high quality of graphene grown on such foils, and the room temperature mobility of the graphene grown on the template stripped foil was three times higher compared to that of one grown on the commercial copper foil. The presented high-quality copper foils are expected to provide large-area substrates for the production of graphene suitable for electronic applications.

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OBJECTIVES: This study presents the concentrations of heavy metals (Cr, Cd, Hg, Zn and Pb) in the water, sediment, and muscle of two fish species from the middle and lower reaches of the Dyje river basin (Dyje, Jihlava, Svratka, Svitava and Trkmanka rivers), in the Czech Rebublic. METHODS: Samples of water, sediment (Tab. 1.) and fish muscle were obtained during the seasons of 2012-2013. As the reference species were chosen chub (Squalius cephalus) and roach (Rutilus rutilus) due to their occurrence in all of the evaluated fishing grounds. RESULTS: The potential ecological risk analysis of heavy metal concentrations in the sediments indicated that nine sites in the middle and lower reaches posed moderate or considerable ecological risk. The health risk analysis of individual heavy metals in fish muscle indicated safe levels for the general population, but there was a possible risk in terms of the total target hazard quotients. The contents of the analysed metals in fish muscles were low at seven sites and did not exceed the values of limits admissible in the Czech Republic. CONCLUSIONS: The increased values of heavy metals in the fish muscle from the Svratka and Svitava rivers may be mainly derived from metal processing, electroplating industries, industrial wastewater and domestic sewage.

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OBJECTIVES: This study presents a rate of bioaccumulation of some metal concentrations in the muscle of five common cyprinid fish species (gudgeon - Gobio gobio, Europen chub - Leuciscus cephalus, barbel - Barbus barbus, roach - Rutilus rutilus, and nase - Chondrostoma nasus). DESIGN: Besides, correlations among selected metals as well as standard length and total weight and order of metal accumulation in the fish muscle were determined. RESULTS: Recorded metal concentrations (mg/kg wet weight basis) ranged as follows: Fe 4.23-22.95, Mn 0.10-0.72, Zn 16.26-166.90, Cu 15.39-25.97, Ni 0.00-3.72, Pb 0.00-1.81, and Cd 0.00-0.11. CONCLUSIONS: The Slovak permissible limit for Cu (10.0 mg/kg), Ni (0.5 mg/kg), Pb (0.2 mg/kg) and Cd (0.05 mg/kg) defined in the Codex Alimentarius for safe human consumption exceeded in 100%, 12%, 6% and 10% of analyzed samples for Cu, Ni, Pb and Cd respectively. On an average, the order of metal concentrations in the fish muscle was: Zn>Cu>Fe>Mn>Ni>Pb>Cd.

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