Modeling the impact of biopores in the soil on root growth and root water uptake

Background and Motivation: Biopores are tubular shaped cavities in the soil formed by biological activity that enable plant roots to reach water and nutrient reservoirs at greater depths. Especially during prolonged drought periods or when the topsoil is nutrient depleted, biopores play an important role in plant nutrition and can help to reduce the required amount of irrigation and fertilization. Direct measurements of the impact of biopores on root growth, root water and nutrient uptake are difficult. 3D root architecture models can help to systematically investigate the influence of different environmental conditions on root system development, to interpret experimental data and to test hypotheses on root– soil interaction processes on different scales. However, parameterization of such models is challenging due to the large effort of measuring root system traits. Methods: We developed a new model approach for the simulation of root system development in soil with biopores, which is based on the analogy between root growth and water flow in porous media and which determines the direction of root growth as a function of soil penetration resistance. This model approach was implemented into the mechanistic 3D model R-SWMS, which allows the simulation of root growth and water flow in the soil- root continuum. To improve the parameterization of the root growth module, we evaluated distributions of different root architecture traits from 2D root images of various wheat varieties. Using data from a field experiment, we then applied the coupled simulation model to evaluate the impact of biopores on root growth and root water uptake under realistic environmental and soil physical conditions. Results: We tested our new model approach on the single root and the root system scale using data from literature. Root trait analysis allowed us to quantify gravitropism and tortuosity parameters and showed the influence of parameter distribution on root foraging performance. Simulations under field conditions and evaluation with extensive field data confirmed that biopores mitigate transpiration deficits in times of water scarcity by allowing roots to take up water from deeper, less dry soil regions. This benefit persisted even under the assumption of reduced root water uptake in biopores due to limited root-soil contact. Conclusions: The good agreement between simulated and observed root growth patterns in structured soil confirmed the new model approach for modelling root growth in soils with biopores. 2D image analysis allowed us to systematically and efficiently analyze root system architectures and to identify model parameters. Plot-scale simulations with different scenarios of environmental and soil physical conditions provided new insights into the influence of biopores on plant transpiration

Model Predictive Control of Grid-Connected Battery Systems to avoid PV-induced Overvoltage

Photovoltaic (PV) power plants are currently built at a high rate, both small ones for single family houses and large-scale plants with a power output in the MW range. This development accelerated even more since the beginning of the energy crisis in 2021. Due to intermittent energy production, large voltage swings may result in the electrical grid, which are challenging for grid and operators. We are considering the problem of overvoltage in times of excessive PV production, which is well documented in the literature. To avoid overvoltage, without PV-curtailment or grid expansion, grid-connected battery systems are proposed. The research focus is on advanced control strategies for such systems which charge and discharge at appropriate times to reduce the overvoltage in the grid while simultaneously minimizing the required battery capacity. The work presented extends a previous contribution of the authors. The analysis was done in a simulation environment (MATLAB/Simulink)

Chiral separation of biologically active compounds by chromatography

- 3 - Abstrakt v češtině Tato diplomová práce je zaměřena na zhodnocení a porovnání enantioselektivního potenciálu dvou kolon, CHIRAL ART Amylose-SA a CDShell-RSP, na sadě 29 chirálních léčiv metodou vysokoúčinné kapalinové chromatografie. Separace enantiomerů probíhala ve třech módech: reverzním, normálním a polárně-organickém. Kolona CHIRAL ART Amylose-SA byla testována v normálním módu, kolona CDShell- RSP v reverzním a polárně-organickém. Kolona CHIRAL ART Amylose-SA obsahuje jako chirální stacionární fázi amylózu tris(3,5-dimethylfenylkarbamát), která je imobilizovaná na porézních silikagelových částicích o velkostí 3 µm. Kolona CDShell-RSP obsahuje jako chirální stacionární fázi hydroxypropyl-β-cyklodextrin, který je kovalentně navázán na pelikulárních částicích o velikosti 2,7 µm. V normálním módu byly použity mobilní fáze složené z hexanu a propan-2-olu. Dále byl testován vliv aditiv (triethylamin, diethylamin, kyselina trifluoroctová, směs diethylaminu a kyseliny trifluoroctové) v mobilní fázi na enantioseparaci analytů. Nejuniverzálnějším aditivem byla směs diethylaminu a kyseliny trifluoroctové. Celkově se na koloně CHIRAL ART Amylose-SA enantioseparovalo 22 analytů, z toho 10 na základní linii. Mobilní fáze pro reverzní mód byly složené z 10 mM octanu amonného (pH 3,0; 4,0; 6,5) a methanolu nebo...- 4 - Abstract in English This diploma thesis is focused on the evaluation and comparison of the enantioselective potential of two columns CHIRAL ART Amylose-SA and CDShell-RSP using a set of 29 chiral drugs in high performance liquid chromatography. The separations of enantiomers were performed in three modes: reversed-phase, normal-phase, and polar- organic mode. The CHIRAL ART Amylose-SA column was tested in normal-phase mode, the CDShell-RSP column in reversed-phase and polar-organic modes. The CHIRAL ART Amylose-SA column contains amylose tris(3,5- dimethylphenylcarbamate) immobilized on 3 µm porous silica gel particles. The CDShell-RSP column contains a chiral selector hydroxypropyl-β-cyclodextrin, which is covalently bonded on 2.7 µm superficially porous particles. In the normal-phase mode, mobile phases composed of hexane and propane-2-ol were used. Furthermore, the effect of various additives (triethylamine, diethylamine, trifluoroacetic acid, and the mixture of diethylamine and trifluoroacetic acid) in the mobile phase on the enantioseparation of chiral drugs was tested. The most universal additive was a mixture of diethylamine and trifluoroacetic acid. A total of 22 chiral drugs were enantioseparated on the CHIRAL ART Amylose-SA column, 10 of them were baseline separated. Mobile phases for...Katedra fyzikální a makromol. chemieDepartment of Physical and Macromolecular ChemistryPřírodovědecká fakultaFaculty of Scienc

Preparation of cytochrome b5 mutants containing photoreactive amino acids, and their crosslinking with the interaction partners

Cytochrom b5 plní funkci přenašeče elektronů v klinicky významném systému oxygenas se smíšenou funkcí (MFO systému). Tento systém se podílí na zvýšení hydrofility látek v první fázi biotransformace xenobiotik a na aktivaci nebo deaktivaci některých léčiv a karcinogenů. Cytochrom b5 ovlivňuje reakce katalyzované terminálními oxygenasami systému - cytochromy P450. Donory elektronů cytochromu b5 jsou NADH:cytochrom b5 reduktasa a NADPH:cytochrom P450 reduktasa Cílem této práce bylo ověřit, zda je možné pomocí metody foto-chemického zesítění fixovat transientní interakce mezi těmito proteiny. Takto získané kovalentní komplexy mohou být dále analyzovány pomocí hmotnostní spektrometrie a poskytují strukturní informace o vazebných místech proteinů. Pro účely foto-síťování byl připraven mutantní cytochrom b5 obsahující v sekvenci v pozici 41 foto-aktivovatelný analog methioninu. Protein jsme exprimovali ve 300 ml limitního média, ve kterém byl methionin nahrazen L-2-amino-5,5-azi-hexanovou kyselinou (foto-methionin), a použili k tomu auxotrofní kmen bakterií E. coli B834(DE3). Míra inkorporace nepřirozené aminokyseliny byla po 16 h exprese stanovena pomocí hmotnostní spektrometrie na přibližně 40 %. Izolací jsme získali celkem 15,4 nmol mutantního cytochromu b5 o koncentraci 76,8 µmol/l. Získaný...Cytochrome b5 is an electron transport protein of a clinically prominent mixed-function oxygenase (MFO) system. This system participates in the first stage of xenobiotic biotransformation. The hydrofility of xenobiotics is increased by introduction of an oxygen atom into their structure. The MFO system also activates or deactivates certain drugs and carcinogens. Cytochrome b5 affects reactions catalyzed by the terminal oxygenases of the system - cytochromes P450. Electrons are donated to cytochrome b5 by redox partners NADH:cytochrome b5 reductase and NADPH:cytochrome P450 reductase. The aim of this work was to demonstrate capability of photo-crosslinking approach to fixate transient interactions within MFO system. Covalent complexes obtained by this technique could be further analyzed by mass spectrometry, which can provide structural information about the binding sites of the proteins. We prepared a mutant cytochrome b5 comprising photo-reactive methionine analogue in the position 41 of the sequence. We expressed the protein employing E. coli B834 (DE3) auxotrophic strain in 300 ml of the limit medium supplemented with L-2- amino-5,5-azi-hexanoic acid (photo-methionine). The rate of the unnatural amino acid incorporation was determined by mass spectrometry and it was about 40 % after 16 hours of...Department of BiochemistryKatedra biochemieFaculty of SciencePřírodovědecká fakult

Polymorphismen des Vitamin D-Rezeptors

Die Zahl der Menschen, die an Osteoporose leiden, nimmt ständig zu. Derzeit leben in Österreich etwa 740.000 Menschen im Alter von über 50 Jahren mit einer Osteoporoseerkrankung. Dies stellt nicht nur ein großes gesundheitliches, sondern aufgrund der verursachten Kosten auch ein wirtschaftliches Problem dar. Viele verschiedene Faktoren tragen zur Entstehung des klinischen Bildes der Osteoporose bei, nämlich verringerte Knochenmasse, poröse Knochenstruktur und daraus resultierende Knochenfrakturen. Einer dieser Faktoren ist die Genetik. Die Knochendichte kann möglicherweise durch die kombinierten Effekte verschiedener Gene, gelegentlich aber auch aufgrund einer Mutation eines einzelnen Gens beeinflusst werden. Vitamin D spielt eine Schlüsselrolle bei der Regulierung der Calciumhomöostase und des Knochenstoffwechsels. Es übt seine Wirkung auf den Knochenmetabolismus durch Regulation der Genexpression aus, vermittelt durch den Vitamin D-Rezeptor (VDR), der als ligandenaktivierter, regulatorischer Transkriptionsfaktor fungiert. Daher ist es naheliegend, eine Verbindung zwischen den Genvarianten des Vitamin D-Rezeptors und dem Risiko für Osteoporose zu vermuten. Nach der Aufklärung der genomischen Struktur des VDR-Gens 1997 wurden zahlreiche Studien über die Assoziation der häufigsten VDR-Genpolymorphismen – ApaI, BsmI, TaqI, FokI, Cdx2, poly(A) – mit Osteoporose veröffentlicht. Die Ergebnisse dieser Studien sind allerdings sehr widersprüchlich und aufgrund der heterogenen Studienpopulationen auch schwer miteinander zu vergleichen. Verschiedene ethnische Gruppen unterscheiden sich außerdem sehr stark hinsichtlich der Häufigkeit bestimmter Allele, Genotypen und Haplotypen. Und auch die Interaktion des VDR-Gens mit anderen Genen und Umweltfaktoren beeinflusst möglicherweise das Risiko an Osteoporose zu erkranken und erschwert die Interpretation vorliegender Studienergebnisse. Dennoch liefern viele der Studien starke Hinweise darauf, dass VDR-Genvarianten einen Einfluss auf bestimmte Merkmale der Osteoporose und anderer Krankheiten, wie Prostata-, Brustkrebs oder Diabetes mellitus ausüben, und dass weiterführende Forschung notwendig ist, um neue Ansätze für Prävention und Behandlung dieser Krankheiten zu finden.The number of people suffering from osteoporosis is constantly increasing. Currently around 740.000 people are affected by this disease in Austria. This fact is not only a matter of health but also a matter of economy, because osteoporosis is causing tremendous costs. Many different factors contribute to the development of the clinical outcome of osteoporosis, which consists of low bone mass and porous bone structure resulting in fractures. One of these factors is genetics. The bone mass density is possibly modified by combined effects of several genes or occasionally due to a mutation of one single gene. Vitamin D is essential for modulating calcium homeostasis and bone metabolism. The vitamin D receptor functions as ligand-activated, regulatory transcription factor and mediates the vitamin D dependent regulation of gene expression. Therefore, the vitamin D receptor gene and its polymorphisms are supposed to influence the risk of osteoporosis. In 1997 the genomic structure of the VDR gene was decoded. Many publications about the association between the most important VDR gene polymorphisms – ApaI, BsmI, TaqI, FokI, Cdx2, poly(A) – and the outcome of osteoporosis followed. The conflicting results of these studies are difficult to interpret due to the heterogeneity of the participants. The frequency of alleles, genotypes and haplotypes differs significantly among different ethnic populations. Gene-gene-interactions as well as gene-environment-interactions probably influence the risk of suffering from osteoporosis and make it hard to interpret the results of available studies. Nevertheless many studies suggest a strong association between VDR gene polymporphisms and some endpoints of osteporosis and other diseases like prostate cancer, breast cancer or diabetes. Further research will be required to find new approaches to prevent and treat those diseases

Roma in Ungarn

Die vorliegende Diplomarbeit beschäftigt sich mit der Situation der Roma-Minderheit in Ungarn. Ausgehend von der Überlegung, dass gesellschaftliche Realitäten vielschichtig und komplex sind, wurde ein multiperspektivischer, interdisziplinärer Zugang gewählt. Unterschiedliche theoretische Strömungen dienen als Werkzeugkästen für die anschließenden Analysen. Geschöpft wird vor allem aus dem Repertoire von politischer Ökonomie und interpretativer Sozialforschung, Antiziganismusforschung, Systemtheorie, Postkolonialismus, Postsozialismus und Dekonstruktion. Es folgen Annäherungen an die Bedingungen des (Über-)Lebens der Roma in Ungarn aus unterschiedlichen Perspektiven. Thematisiert werden historische Kontinuitäten und Brüche des Neben-, Mit- und Gegeneinander von Magyaren und Roma, das spezielle Machtfeld Kultur und im Zusammenhang damit mediale Präsenz beziehungsweise mediale Repräsentation und Beispiele der Kunstproduktion von Roma als subversive Strategien, und schließlich Fragen der Identität und Definitionsmacht. Auf dem Hintergrund dieser Ausführungen findet die anschließende Analyse ausgewählter Themenfelder statt. Hierbei werden gesellschaftliche Dynamiken von Inklusion und Exklusion herausgearbeitet, unterschiedliche Interessen definiert und Machtstrukturen offengelegt. Die sozialistische Vergangenheit Ungarns und die Transformation der Gesellschaft nach dem Zusammenbruch des Realsozialismus weisen Brüche aber auch Kontinuitäten auf, die einen tieferen Kontext für den sozialen Abstieg eines großen Teils der Roma- Bevölkerung im postsozialistischen Ungarn liefert. Entwicklungen auf supranationaler Ebene haben indes Auswirkungen auf konkrete politische Agenden, die wiederum die Situation der Minderheiten im Land maßgeblich beeinflussen. Die Genese der ungarischen Minderheitenpolitik wird in diesem Zusammenhang thematisiert. Ein Blick auf die Praktiken in den Büros der staatlichen Wohlfahrt schließlich zeigt, wie sich globale Diskurse bis auf die Ebene der Sozialarbeit und letztlich der Alltagskommunikation zwischen Roma und Magyaren auswirken.This thesis deals with the situation of the Roma minority in Hungary. The initial standpoint hereby is the consideration that societal realities are complex and multilayered, therefor a multi-perspective approach seems accurate. Several different theoretical currents provide the tools for the following analyses. Especially the theoretical considerations and instruments of Interpretative Social Science, Antigypsyism-research, Systems Theory, Postcolonialism, Postsocialism and Deconstruction are being consulted. Such equipped, the text approaches the terms and means of the survival of the Roma in Hungarian mainstream society from different perspectives. It looks into historical continuities as well as disjunctions of interaction between Roma and non-Roma in Hungary, before turning to the arena of culture and media, examining forms of representation and production as well as subversive strategies, which leads to questions of identity and the discursive power of definition. To the background of this initial approaches, in-depth analyses of selected thematic fields take place, showing the dynamics of inclusion and exclusion, the variety of different interests and the existence of underlying structures of power. The socialist past of the country and the transformation of its society after the collapse of European state socialism shows disruptions as well as continuities, which provide for a distinctive context for the social decline of great parts of the Roma population in postsocialist Hungary. Meanwhile, supranational developments materialise into specific policies, which again influence the situation of the minorities on a national level. In this respect, the development of Hungarian minority policies is discussed. Finally, a (imaginary) visit to Hungarian state welfareoffices provides an understanding of the impact of global discourses on a local level, the changing working conditions of social workers and really the daily communication between Roma and Magyars

Non-thermal processing effects on fruits and vegetables phytonutrients

The health‐promoting effects of many phytonutrients are attributed mainly to their antioxidant activity, although there may be other modes of action. The demand for high quality food with high phytonutrients content is attracting a lot of attention, as it provides health benefits and has been shown to possess antimicrobial, antiviral, antiparasitic, anti‐inflammatory, antioxidant, antimutagenic, and antitumor effects. To maintain food quality at the highest possible levels, there is a need to develop novel processing techniques such as non‐thermal processing. This chapter discusses novel non‐thermal processing techniques, including ultraviolet radiation, high pressure processing (HPP), dense phase carbon dioxide (DPCD), ultrasound processing, and pulsed electric field (PEF). The application of HPP and its effects on quality attributes, specific to the phytochemical compounds in fruits and vegetables. High pressure offers a technology that can achieve the food safety properties of heat‐treated foods while meeting consumer demand for fresher tasting food products

Measuring root system traits of wheat in 2D images to parameterize 3D root architecture models

Background and aimsThe main difficulty in the use of 3D root architecture models is correct parameterization. We evaluated distributions of the root traits inter-branch distance, branching angle and axial root trajectories from contrasting experimental systems to improve model parameterization.MethodsWe analyzed 2D root images of different wheat varieties (Triticum aestivum) from three different sources using automatic root tracking. Model input parameters and common parameter patterns were identified from extracted root system coordinates. Simulation studies were used to (1) link observed axial root trajectories with model input parameters (2) evaluate errors due to the 2D (versus 3D) nature of image sources and (3) investigate the effect of model parameter distributions on root foraging performance.ResultsDistributions of inter-branch distances were approximated with lognormal functions. Branching angles showed mean values <90°. Gravitropism and tortuosity parameters were quantified in relation to downwards reorientation and segment angles of root axes. Root system projection in 2D increased the variance of branching angles. Root foraging performance was very sensitive to parameter distribution and variance.Conclusions2D image analysis can systematically and efficiently analyze root system architectures and parameterize 3D root architecture models. Effects of root system projection (2D from 3D) and deflection (at rhizotron face) on size and distribution of particular parameters are potentially significant