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2462. Atmosférický aerosol: přehled přístrojů k jeho měření a nové resuspenzní zařízení Přírodovědecké fakulty UK
- Creator:
- Civiš, Martin, Hovorka, Jan, and Thimmaiah, Devraj
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- Univerzita Karlova., Přírodovědecká fakulta, znečištění atmosféry, aerosoly, atmosphere pollution, aerosols, 2, and 504
- Language:
- Czech
- Description:
- Aerosolové částice se vyskytují všude okolo nás v mnoha různých formách, například jako prach, mlha, kouř, dým nebo smog. Tyto částice ovlivňují dohlednost, klima, zdraví obyvatel a jejich kvalitu žvota. Atmosférický aerosol je v současné době jedním z největších problémů znečištění ovzduší. Tento článek dokumentuje vznik aerosolu, formy jeho výskytu a depozice. Dále popisujeme nejužívanější metody jeho odběru a monitorování. V závěrečné části jsou ukázány první výsledky získané pomocí nového zařízení na zkoumání resuspenze aerosolu - resuspenzní komory., Martin Civiš, Jan Hovorka, Devraj Thimmaiah., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2463. Atomic ratio of N to P influences the impact of UV irradiance on photosynthesis and growth in a marine dinoflagellate, Alexandrium tamarense
- Creator:
- Guan, W. C. and Li, L.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- květy řas, efektivní fotochemická účinnost, algal bloom, effective photochemical efficiency, nutrient stoichiometry, solar ultraviolet radiation, 2, and 581
- Language:
- Multiple languages
- Description:
- The effects of the atomic ratio of N to P (N:P) on the response of Alexandrium tamarense to UV radiation (UVR) were investigated in this study. Artificial sea water of 5 different N:P ratios for indoor culture and with 3 different N:P ratios for outdoor culture were used for a period of 14 and 9 d, respectively. The short-term response of cells to UVR was analyzed using a fluorometer. Cells that acclimated to nutrient conditions at the Redfield value (16:1) showed the fastest growth rate and highest pigment concentrations in both indoor and outdoor conditions, compared to those acclimated to the non-Redfield conditions. Moreover, these physiological parameters were functions of the N:P ratio according to a two-order equation (y = a + bx + cx2, R2>0.95). The fluorescence data of indoor cultures showed that A. tamarense grown at 16:1 (N:P) exhibited the greatest ratio of repair rate/damage rate (r/k) and minimum level of UVR-induced inhibition. among those grown at all of the N:P ratios following UVR exposure. Outdoor cultures had the same patterns of fluorescence as indoor cultures, but the less UVR-induced inhibitions were detected compared the former with the latter. The following three parameters, the r/k, level of inhibition caused by the two radiation treatments following 60 min of exposure (PAR and PAB, respectively), and level of UVR-induced inhibition, were also functions of the N:P ratio according to the two-order equation (R2>0.96). Further, there was a negative correlation between UVR-induced inhibition and the r/k ratio. In summary, the Redfield value (16:1) was the optimal nutrient stoichiometry for the protection of A. tamarense against the deleterious effects of UVR. Results were not impacted by previous light history experienced by cells., W. C. Guan, L. Li., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2464. ATP-Binding Cassette (ABC) Transporters in Human Metabolism and Diseases
- Creator:
- Štefková, J., Poledne, R., and Hubáček, J.A.
- Type:
- article, model:article, and TEXT
- Subject:
- ABC transporter, Lipid metabolism, Cholesterol, and Mutation
- Language:
- English
- Description:
- The ATP-binding cassette (ABC) superfamily of active transporters involves a large number of functionally diverse transmembrane proteins. They transport a variety of substrates including amino acids, lipids, inorganic ions, peptides, saccharides, metals, drugs, and proteins. The ABC transporters not only move a variety of substrates into and out of the cell, but also are also involved in intracellular compartmental transport. Energy derived from the hydrolysis of ATP is used to transport the substrate across the membrane against a concentration gradient. The typical ABC transporter consists of two transmembrane domains and two nucleotide-binding domains. Defects in 14 of these transporters cause 13 genetic diseases (cystic fibrosis, Stargardt disease, adrenoleukodystrophy, Tangier disease, etc.). Mutations in three genes affect lipid levels expressively. Mutations in ABCA1 cause severe HDL deficiency syndromes called Tangier disease and familial high-density lipoprotein deficiency, which are characterized by a severe deficiency or absence of high-density lipoprotein in the plasma. Two other ABCG transporters, ABCG5 and ABCG8, mutations of which cause sitosterolemia, have been identified. The affected individuals absorb and retain plant sterols, as well as shellfish sterols.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2465. ATP-sulfurylase activity, photosynthesis, and shoot dry mass of mustard (Brassica juncea L.) cultivars differing in sulfur accumulation capacity
- Creator:
- Nazar, R., Khan, N. A., and Anjum, N. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- dry mass, leaf area, nitrogen content, and sulfate transport index
- Language:
- Multiple languages
- Description:
- Sulfur (S) is an essential nutrient element required in a large quantity by mustard. S regulates photosynthesis and plant growth through improving nitrogen (N) acquisition. Mustard cultivars Alankar, Varuna, Pusa Jai Kisan, and SS2 differing in S accumulation capacity calculated as sulfate transport index (STI) were tested for ATP-sulfurylase activity, S and N accumulation, photosynthesis, and shoot dry mass (DM) at 30 and 60 d after sowing (DAS). The activity of ATP-sulfurylase, shoot N content, net photosynthetic rate (PN), leaf area, and shoot DM of the cultivars were in the order: Pusa Jai Kisan>Alankar>Varuna>SS2. ATP-sulfurylase activity was strongly and positively correlated with PN and shoot DM in all the cultivars. Hence ATP-sulfurylase activity may be used as a physiological trait for augmenting photosynthesis and shoot DM. and R. Nazar, N. A. Khan, N. A. Anjum.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2466. Atraktivita a důveryhodnost
- Creator:
- Šrámková, Lenka
- Type:
- article, model:article, and TEXT
- Subject:
- fyzická atraktivita, osobní atraktivita, důvěryhodnost, atraktivita tváře, policie, physical attractiveness, personal attractiveness, credibility, face attractiveness, and police
- Language:
- Czech
- Description:
- Jelikoţ je atraktivita často diskutovaným tématem, tato studie se jí zabývá jakoţto fenoménem sociální psychologie, především jejím vlivem při sociálním kontaktu. Provizorně byla zmapována orientační typologie lidí podle vzhledu (dvanáct kategorií) a do nich byli nalezeni vhodní zástupci. Cílem výzkumu pak bylo zjistit pořadí kategorií podle vnímané atraktivity a přisuzované důvěryhodnosti a vztah mezi těmito dvěma komponentami. Fotografie jsou portrétové a je jich čtyřiadvacet (dvanáct muţů a dvanáct ţen). Hlavním cílem tohoto šetření je však především připravit podklad pro plánovaný výzkum vlivu fyzické atraktivity člověka na jeho posouzení a ohodnocení jinými lidmi, konkrétně dopravními policisty, protoţe právě oni jsou často vystaveni rozhodování se na základě „prvního dojmu“. Respondenti tohoto předvýzkumu byli muţi ve věku 20 – 35 let, budoucí policisté, kteří portrétované subjekty osobně neznali. Výsledky ukázaly korelaci mezi percipovanou atraktivitou a přisuzovanou důvěryhodností (r = 0,538 pro muţe a r = 0,668 pro ţeny, resp. r = 0,748 pro muţe, r = 0,864 pro ţeny). Do následujícího výzkumu byly na základě tohoto předvýzkumu vybrány fotografie osob hodnocených jako nejatraktivnější, resp. nejméně atraktivní. and Attractiveness is a widely discusses topic today, this paper focuses on attractiveness as a phenomenon of social psychology and especially on its influence on social contacts. An orientation typology of humans according to their appearance (twelve categories) was mapped out and the appropriate representatives of each category were found. The goal of the research was to state the order of these categories according to perceived attractiveness and ascribed credibility and to trace the relation between these two components. There were twenty-four portrait photographs (twelve men and twelve women). However, the main target of this study was to prepare the background for the planned research on the influence of the physical attractiveness of a person on the way he or she is viewed and evaluated by others, to be more specific, by traffic policemen as they often make decisions based on their "first impression". Respondents were men, 20-35 years old, soon-to-be policemen and they did not personally know the people on the portraits. The results show correlation between the perceived attractiveness and ascribed credibility (r = 0,538 for men and r = 0,668 for women). On the basis of this pre-study, the portraits of persons evaluated as the most attractive and the least attractive were chosen for the following research.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2467. Atrial contribution to ventricular ejection in sequentially paced patients
- Creator:
- Kvasnička, J., Tauchman, M., Kovář, D., Jandík, J., Gajdošová, I., and Rejchrt, P.
- Type:
- article, model:article, and TEXT
- Subject:
- atrial contribution, pulse pressure, DDD pacing, AV optimization, and AV interval
- Language:
- English
- Description:
- A new method for quantitative assessment of the atrial contribution to ventricular ejection in sequentially paced patients is described. The atrial contribution (AC) has been defined as the pulse pressure decrement (invasive arterial measurement by a canulla inserted into the brachial artery), expressed in percent of the control pulse pressure, induced by switching off the atrium activating impulse for one beat In 17 patients, the AC was found to be atrioventricular (AV) interval dependent, the measurements were well reproducible (the mean difference between two measurements at different times was 93 %, S.D. 8.4). For the AV interval of 170 ms, it was found to be 29.3 % (+8.9) in patients with the sick sinus syndrome, 27.0 % (+3.2) in patients with complete AV block and only 10.8 % (+2.1) a in patient with complete AV block and heart dysfunction.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2468. Atrioventricular conduction time in fetuses assessed by doppler echocardiography
- Creator:
- Viktor Tomek, Jan Janoušek, Reich, O., Jiří Gilík, Roman Antonín Gebauer, and Jan Škovránek
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, prenatální ultrasonografie, dopplerovská echokardiografie, prenatal ultrasonography, Doppler echocardiography, atrioventricular block, fetus, 14, and 612
- Language:
- English
- Description:
- We performed measurement of mechanical atri oventricular conduction time intervals in human fetuses assessed by Doppler echocardiography and provided re ference values. We found that atrioventricular cond uction time interval was prolonged with gestational age and decreased with increasing fetal heart rate. No correlation between gestat ional age and heart rate was found. Using normal limits established by this study, mechanical atrioventricular interval >135 ms in the 20th week and/or >145 ms in the 26th week of gestation could be suspected of having the first-degree AV block. We compared reference values with fetuses of mothers with anti-SSA Ro/SSB La autoantibodies, being in risk of isolated congenital heart block development. One of 21 fetuses of mothers with positive autoantibodies was affected by prolonged atrioventricular interval according to the established limits, with sinus rhythm after the birth., V. Tomek ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2469. Atropa Belladonna L. water extract: modulator of extracellular matrix formation in vitro and in vivo
- Creator:
- Petr Gál, Vasilenko, T., Kováč, I., Kostelníková, M., Jakubčo, J., Pavol Szabo, Barbora Dvořánková, František Sabol, Hans-Joachim Gabius, and Karel Smetana
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, phytotherapy, aqueous extract, wound healing, fibroblast, keratinocyte, inflammation, 14, and 612
- Language:
- English
- Description:
- Previously, we found that treatment of cutaneous wounds with Atropa belladonna L. (AB) revealed shortened process of acute inflammation as well as increased tensile strength and collagen deposition in healing skin wounds (Gál et al. 2009). To better understand AB effect on skin wound healing male SpragueDawley rats were submitted to one round full thickness skin wound on the back. In two experimental groups two different concentrations of AB extract were daily applied whereas the control group remained untreated. For histological evaluation samples were removed on day 21 after surgery and stained for wide spectrum cytokeratin, collagen III, fibronectin, galectin-1, and vimentin. In addition, in the in vitro study different concentration of AB extract were used to evaluate differences in HaCaT keratinocytes proliferation and differentiation by detection of Ki67 and keratin-19 expressions. Furthermore, to assess ECM formation of human dermal fibroblasts on the in vitro level fibronectin and galectin-1 were visualized. Our study showed that AB induces fibronectin and galectin-1 rich ECM formation in vitro and in vivo. In addition, the proliferation of keratinocytes was also increased. In conclusion, AB is an effective modulator of skin wound healing. Nevertheless, further research is needed to find optimal therapeutic concentration and exact underlying mechanism of action., P. Gál ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2470. Attaboy
- Creator:
- Vyskočil, František
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public