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Methodology for identification of pollution sources using PMF for strategic decision making in air protection - update 2023
Horník, Štěpán ; Sýkora, Jan ; Pokorná, Petra
The presented methodology proposes utilizatíon of the spectroscopy of nuclear magnetic resonance (NMR) as another analytical technique for the identification of compounds in atmospheric aerosols. This technique makes significantly increases the number of deterined substances and thus a number of possible markers, which can be subsequently used together with other methods to identify sources of air pollution using advanced statistical\nanalysis. Among the markers determined by NMR spectroscopy there are several organic and sulfonic acids or carbohydrates, wich are characteristic for relevant sources of air pollution. The updated methodology also shows the identification of a biogenic source that previous methodologies were not able to determine.
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Dependence of aerosol activation on meteorological conditions
Zíková, Naděžda ; Pokorná, Petra ; Sedlák, Pavel ; Ždímal, Vladimír
Four intensive in-situ campaigns focused on aerosol-cloud interactions were performed in the autumn and spring months from Nov 2018 to Apr 2020 at Milešovka Mountain in Czechia to bring more insight into size-dependent aerosol activation and dependence on its origin for a wide variety of meteorological parameters. Most activated particles were larger than 100 nm, with a mode over 200 nm. For the description of the changes in the activation, no effect of photochemistry was found, in contrast, some dependence on relative humidity, temperature, wind speed, and liquid water content (LWC) proved to be useful. The strongest connection was found between activation and LWC. For LWC below 0.1 g/m3, in the LWC-limited regime, the LWC values and variables effecting the LWC were the main factors influencing the activation, while different parameters could have played a role at LWCs over 0.1 g/m3, in the LWC-independent regime.
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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.
Plný tet: PDF
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Motivating factors influencing the work of directors of nursery school
Pokorná, Pavlína ; Trojanová, Irena (advisor) ; Tureckiová, Michaela (referee)
Master's thesis entitled Motivating factors influencing the work of directors of nursery schools aims to identify motivational factors influencing the work of headmasters. The main objective of the research is to determine which of motivation, stimulation, and demotivating factors affect headmasters of nursery schools of the Pardubice Region. Based on quantitative and qualitative research lead to the fulfillment of specific objectives. The first partial objective is to conclude from created questions for a research and carrying out research among nursery schools among Managers of Pardubice region through a questionnaire survey and subsequent analysis of the data,what motivational factors, stimulation, demotivating and to what extent, affect the work of directors of nursery schools in Pardubice region. The second partial objective is to compare the motivational factors influencing the work of selected directors surveyed of nursery schools in Pardubice region at different stages of their professional development and to identify changes in the scope of these factors of motivation. The research suggests that motivational factors influence the work of directors rather moderately, stimulatory factors in their work are mostly highly motivating and demotivating factors are strongly demotivating. All the...
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Kinetically guided therapy with gentamicin in neonates with sepsis during the first week of life
Pokorná, Pavla ; Chládek, Jaroslav (advisor) ; Perlík, František (referee) ; Patočková, Jitka (referee)
Gentamicin (Ge) belongs to the group of aminoglycoside antibiotics frequently used in the treatment of neonates with sepsis in combination with betalactams. The first part of the disertation investigates a kinetically guided therapy with gentamicin (Ge) and the impact of covariates on pharmacokinetics/pharmacodynamics (PK/PD) while the second part describes the tolerability of treatment. This open-label, prospective study included preterm and term neonates (n=108) who experienced critically illness during the first week of life and were treated with Ge and admitted to the neonatal intensive care unit. The primary goal of the study was to perform a pharmacokinetic study after the first dose of Ge. The influence of covariates on PK was analyzed (body weight, gestational age-GA, fluid retention, persistent ductus arteriosus-PDA, postnatal age, therapeutic hypothermia-HT) as well as the success rate in the achivement of target therapeutic concentrations in the first week of pharmacotherapy. Fitting of the parameters of two-compartment model to the four plasma concentrations of Ge (CplGe) concentations after the first dose was used to estimate individual PK of Ge: distribution volume (Vd1) and clearance (CL1). Neonates were stratified into four groups according to GA and the presence of a PDA (S1-PDA=18,...
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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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