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NMR Aerosolomics Study of Water-Soluble Organic Compounds in Size-Resolved Particulate Matter
Horník, Štěpán ; Vodička, Petr ; Pokorná, Petra ; Schwarz, Jaroslav ; Ždímal, Vladimír ; Sýkora, Jan
Organic aerosols (OA) account for a significant fraction (10 – 90%) of atmospheric particulate matter (Hallquist et al., 2009). The composition of organic aerosols is very complex and is usually characterized by their water solubility. Water-soluble organic compounds (WSOC) constitute a large fraction of OA (10 – 80%) and consist of chemical species containing oxygenated functional groups such as hydroxyl, carboxyl, or carbonyl groups. NMR spectroscopy represents an alternative to commonly used techniques (gas chromatography-mass spectrometry, liquid chromatography-based techniques) for WSOC analysis. Our recently introduced method, called NMR aerosolomics, allows quantitative analysis of dozens of individual compounds from different aerosol samples. An important part of the characterization of aerosols is their classification by particle size. The analysis of individual compounds in the size-resolved fractions of the WSOC class has been performed only in a few studies that focus mainly on a particular subclass of compounds or use multiple analytical techniques.
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Physicochemical Properties and Origin of PM1 Measured at a Rural Background Site
Pokorná, Petra ; Zíková, Naděžda ; Vodička, Petr ; Lhotka, Radek ; Mbengue, Saliou ; Holubová Šmejkalová, A. ; Riffault, V. ; Ondráček, Jakub ; Schwarz, Jaroslav ; Ždímal, Vladimír
This study assesses the variability of organic aerosol (OA) sources monitored at the rural background site Frýdlant. Non-refractory PM1 was evaluated in two seasons of\n2021. The positive matrix factorization with the multi-linear engine was used to determine the sources of OA at Frýdlant site, with four factors resolved both in winter and\nsummer.
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Chemical composition and sources of atmospheric aerosols at the Frýdlant background station
Lhotka, Radek ; Pokorná, Petra ; Vodička, Petr ; Zíková, Naděžda ; Ondráček, Jakub ; Arora, S. ; Poulain, L. ; Hermann, H. ; Schwarz, Jaroslav ; Ždímal, Vladimír
This study assesses the variability of organic aerosol (OA) sources monitored at the rural background site Frýdlant. Non-refractory PM1 was evaluated in two seasons of\n2021. The positive matrix factorization with the multi-linear engine was used to determine the sources of OA at Frýdlant site, with four factors resolved both in winter and\nsummer.
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In vitro effect of flavonoids on activity of selected biotransformation enzymes in intestinal cell lines
Pokorná, Petra ; Szotáková, Barbora (advisor) ; Matoušková, Petra (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Petra Pokorná Supervisor: Doc. Ing. Barbora Szotáková, Ph.D. Title of diploma thesis: In vitro effect of flavonoids on activity of selected biotransformation enzymes in intestinal cell lines Anthocyanins belong to a class of flavonoids which are part of major natural pigments in plants. They are considered to be very beneficial for the human organism. Anthocyanins are widely consumed as fruits, vegetables and red wine and they represent significant constituents of dietary supplements. The popularity of dietary supplements with high concentrations of flavonoids is still increasing, but in addition to positive effects on human health it can also have side effects influence drug metabolizing enzymes and thus affect either desirable or undesirable effects of many drugs. In this thesis in vitro effect of some anthocyanidins (cyanidin, delphinidin, malvidin, pelargonidin) on the proliferation of the intestinal cell line Caco-2 was investigated using the assay of metabolic activity (MTT) and determination of the integrity of the cytoplasmic membrane of cells (neutral red). Then was studied their effect on the activity of selected biotransformation enzymes: glutathione S-transferase (GST),...
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English translation equivalents of Czech prepositions "s" and "na" (in parallel electronic texts)
Pokorná, Petra ; Malá, Markéta (advisor) ; Klégr, Aleš (referee)
The aim of this study is to analyze and describe the English translation equivalents of two Czech prepositions 'na' and 's' (including its vocalized form 'se') in texts of contemporary Czech fiction and their English translations. The study is divided into three major parts: a theoretical overview, an analysis and a conclusion. The theoretical survey consists of two parts, in which the syntactic and semantic characteristics of prepositions in general are dealt with and the status of prepositions in Czech and English is compared. The first, syntactic part provides an overview of the syntactic functions of the prepositional phrases. The semantic part describes the treatment of prepositional meanings in Czech and English grammars and focuses on the meanings attributed to 'na' and 's' in Czech grammars and monolingual and bilingual Czech-English dictionaries. The analytical part of the present paper will be preceded by a brief specification of the data on which the analysis was based. The analysis itself is divided into two parts, each of which comprises two subsections. The first analytical part compares the syntactic functions of the Czech prepositional phrases and their English counterparts, the first subsection providing an analysis of the preposition 'na', the other examining the preposition 's/se'. In the...
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Pre-hospital phase of acute myocardial infarction from the patient's perspective
Pokorná, Petra ; Hocková, Jana (advisor) ; Jankovcová, Kateřina (referee)
Acute myocardial infarction (AMI) represents severe complication of atherosclerotic vascular disease. Despite therapeutic advances and better risk factor control, acute myocardial infarction remains the leading cause of death worldwide. Goal of this thesis was to interview a group of patients hospitalized for acute myocardial infarction and evaluate their knowledge of disease course, perception of disease representing a sudden change of health status, awareness of disease symptoms and motivation for future lifestyle changes. Quantitative research with inductive approach was chosen for our research. Data was collected using individualized non-standardized semi-structured interview. Seven selected patients hospitalized for acute myocardial infarction with ST elevation were entered into our analysis. All the patients were informed in advance about our research methods and ethical aspects. All the participants had insufficient awareness of AMI symptoms. However, intensity of disease symptoms was severe, so they contacted health system early. Majority of them called emergency service. Level of education had significant impact on patient behavior. Patients with university degree had the best awareness of disease symptoms and shortest times from symptom onset to medical system contact. They were...
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Source apportionment of atmospheric aerosol fraction using by highly time resolved characterisation
Pokorná, Petra
The effective air quality management in the heavy polluted areas has to be based on high-quality monitoring with properly designed monitoring network and targeted measurements, which provided information required to source apportionment. The thesis aim was to apportion sources of atmospheric aerosol based on highly time resolved data of mass concentration of size segregated aerosol, its temporal and spatial variability, elemental composition, OC/EC and size distribution of carcinogenic polyaromatic hydrocarbons. Sampling campaigns went during winter and summer in small settlement Březno by Chomutov, residential area Ostrava - Radvanice a Bartovice and Mladá Boleslav in the years 2008 - 2010, 2012, 2013. We determined mass concentrations of PM10, PM1-10, PM1.15-10 and PM0.15-1.5 and their size fraction ratios. Based on the size ratios, the source apportionment of fine fraction (PM0.15-1.15) with focus on PM0.34-1.15 is crucial. We examined seasonal and spatial variability of PM10, PM.2.5, PM1 and PM1-10. Based on the examination, we obtained representative highly-time resolved data with regards to season and sampling locality. We analysed dynamic of size distribution of particle-bond eight carcinogenic polycyclic hydrocarbons. Based on the results the source apportionment of PM0.34-1.15 is crucial....
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The origin of air pollution on the basis of one year measurements of PM2.5 and PM10 at two urban background stations in Prague
Schwarz, Jaroslav ; Pokorná, Petra ; Rychlík, Š. ; Škáchová, H. ; Smolík, Jiří ; Ždímal, Vladimír ; Vlček, O. ; Hůnová, I.
The particulate matter (PM) mass concentration in cities corresponds to the sum of the concentrations measured at the background stations and the difference between the city and background stations. For this reason, at high background concentrations of PM, the result of emission reduction measures is low. Most of the reported episodes of increased PM concentrations in winter in central European cities are caused by sources of local or regional origin from the combustion of coal and / or biomass for heating purposes. Improvement of air quality in cities is possible provided that causality is understood, especially when it comes to atmospheric aerosol and its concentration, sources and origin.\nThe aim of the work was to determine the origin of air pollution in Prague on the basis of one year parallel measurements of atmospheric aerosol at two urban background stations.\n\n
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22020011314370 - PDF
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