From the very first experiments performed with high intensity laser pulse interaction with matter it has been clear that laser produced plasma is a rich source of emitting high energetic particles and electromagnetic radiation in a broad spectral range. In this article a basic phenomenon of nonlinear processes of high intensity laser pulse interaction and related acceleration of particles in laser induced thermal plasma are outlined. possible applications of ultra-short mono-energetic electron beams (with divergence and small energy spread) which are generated during this interaction are also discussed., Už od vykonania prvých experimentov použitím intenzívneho laserového žiarenia s hmotou bolo zrejmé, že laserom indukovaná plazma je bohatým zdrojom vysokoenergetických častíc a elektromagnetického žiarenia v širokej škále spektrálnych oblastí. V článku je bližšie uvedená problematika nelineárnych javov počas vysokointenzívnych laserových interakcií a s tým súvisiacu aj akceleráciu častíc v laserom indukovanej termálnej plazme. Taktiež sú uvedené aj potencionálne možné aplikácie vysokoenergetických elektrónových zväzkov, které sú generované pri týchto interakciách a dosahujú rýchlosti blízke rýchlosti svetla., Richard Viskup, Peter Lukáč., and Obsahuje bibliografii
Kolobeh hmôt v zemskéj kôre a na jej povrchu je velmi výrazne ovplyvňovaný fyzikálnymi silami, ktoré na teleso planéty pôsobia zvonku - od účinku vektorov jej vlastného pohybu, cez gravitačné pôsobenie jej obežnice - Mesiaca a blízkych planét, až po fluktuácie prísunu energie z nám najbližšej hviezdy - Slnka. Rozoznanie záznamu týchto vplyvov v horninovom slede a porozumenie im je cestou vedúcou k spresneniu astronomickej časomernej škály a detailnejšiemu poznaniu procesov formovania Zeme a života na nej., Rock cycling both in the Earth‘s crust and on its surface is impressively controlled by physical forces that act on the body of our planet from the outside, i.e. from the effect of its own motion vectors, through the gravity of the Moon and nearby planets to fluctuations in the energy input from our nearest star, i.e. the Sun. The recognition of evidence of these influences in the rock sequence and their understanding is a method used to specify the astronomical time scale and to understand, in detail, processes of formation of the Earth and indeed life on it., Jozef Michalík., and Obsahuje seznam literatury
Because greater Akt substrate of 160 kDa (AS160) phosphorylation has been reported in insulin-stimulated skeletal muscles without improved Akt activation several hours post-exercise, we hypothesized that prior exercise would result in attenuated AS160 dephosphorylation in insulin-stimulated rat skeletal muscle. Epitrochlearis muscles were isolated from rats that were sedentary (SED) or exercised 3 h earlier (3 h postexercise; 3hPEX). Paired muscles were incubated with [3H]-2-deoxyglucose (2-DG) without insulin or with insulin. Lysates from other insulin-stimulated muscles from SED or 3hPEX rats were evaluated using AS160Thr642 and AS160Ser588 dephosphorylation assays. Prior exercise led to greater 2-DG uptake concomitant with greater AS160Thr642 phosphorylation and a non-significant trend (P=0.087) for greater AS160Ser588. Prior exercise also reduced AS160Thr642 and AS160Ser588 dephosphorylation rates. These results support the idea that attenuated AS160 dephosphorylation may favor greater AS160 phosphorylation post-exercise., E. B. Arias, H. Wang, G. D. Cartee., and Seznam literatury
Considerable evidence demonstrates that phenotypic switching of vascular smooth muscle cells (VSMCs) is influenced by aging and hypertension. During phenotypic switching, VSMCs undergo a switch to a proliferative and migratory phenotype, with this switch being a common pathology in cardiovascular diseases. The aim of this study was to explore the joint influence of age and hypertension on thoracic aortic smooth muscle phenotypic switching and the balance of Akt and mitogen-activated protein kinase (MAPK) signaling during this switch. Different ages of spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) were used to establish hypertension and aging models. The phenotypic state was determined by detecting the marker proteins α-SM-actin, calponin, and osteopontin (OPN) via immunohistochemical staining and Western blot. Signaling proteins associated with the Akt and MAPK pathways were detected in rat thoracic aorta using Western blot. Both aging and hypertension caused a decrease in contractile (differentiated) phenotype markers (α-SM-actin and calponin), while the synthetic (proliferative or de-differentiated) phenotype maker was elevated (OPN). When combining hypertension and aging, this effect was enhanced, with Akt signaling decreased, while MAPK signaling was increased. These results suggested that VSMCs phenotype switching is modulated by a balance between Akt and MAPK signaling in the process of aging and hypertension., Lin Zhang, Zhaoxia Xu, Ying Wu, Jingwen Liao, Fanxing Zeng, Lijun Shi., and Obsahuje bibliografii
Dozimetrie interního ozáření je oblast radiační ochrany, která se snaží stanovit dávku způsobenou přítomností radionuklidů v lidském těle. Popíšeme zde obecný přístup k hodnocení dávky a ukážeme přehled nových trendů v této oblasti. Pozornost je věnována především biokinetickým modelům a aplikacím matematických fantomů pro potřeby kalibrace měření in vivo., The assessment of the dose from internally incorporated radionuclides in a human body is the domain of internal dosimetry. This paper describes the general approach to dose assessment and discusses developments and new trends in the area. Special focus is given to biokinetic modeling and the application of mathematical models for calibration purposes of in-vivo measurements., Tomáš Vrba., and Obsahuje bibliografii