899 resultados para binary to multi-class classifiers


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Progress in miniaturization of electronic components and design of wireless systems paved the way towards ubiquitous and pervasive communications, enabling anywhere and anytime connectivity. Wireless devices present on, inside, around the human body are becoming commonly used, leading to the class of body-centric communications. The presence of the body with all its peculiar characteristics has to be properly taken into account in the development and design of wireless networks in this context. This thesis addresses various aspects of body-centric communications, with the aim of investigating network performance achievable in different scenarios. The main original contributions pertain to the performance evaluation for Wireless Body Area Networks (WBANs) at the Medium Access Control layer: the application of Link Adaptation to these networks is proposed, Carrier Sense Multiple Access with Collision Avoidance algorithms used for WBAN are extensively investigated, coexistence with other wireless systems is examined. Then, an analytical model for interference in wireless access network is developed, which can be applied to the study of communication between devices located on humans and fixed nodes of an external infrastructure. Finally, results on experimental activities regarding the investigation of human mobility and sociality are presented.

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Power electronic converters are extensively adopted for the solution of timely issues, such as power quality improvement in industrial plants, energy management in hybrid electrical systems, and control of electrical generators for renewables. Beside nonlinearity, this systems are typically characterized by hard constraints on the control inputs, and sometimes the state variables. In this respect, control laws able to handle input saturation are crucial to formally characterize the systems stability and performance properties. From a practical viewpoint, a proper saturation management allows to extend the systems transient and steady-state operating ranges, improving their reliability and availability. The main topic of this thesis concern saturated control methodologies, based on modern approaches, applied to power electronics and electromechanical systems. The pursued objective is to provide formal results under any saturation scenario, overcoming the drawbacks of the classic solution commonly applied to cope with saturation of power converters, and enhancing performance. For this purpose two main approaches are exploited and extended to deal with power electronic applications: modern anti-windup strategies, providing formal results and systematic design rules for the anti-windup compensator, devoted to handle control saturation, and “one step” saturated feedback design techniques, relying on a suitable characterization of the saturation nonlinearity and less conservative extensions of standard absolute stability theory results. The first part of the thesis is devoted to present and develop a novel general anti-windup scheme, which is then specifically applied to a class of power converters adopted for power quality enhancement in industrial plants. In the second part a polytopic differential inclusion representation of saturation nonlinearity is presented and extended to deal with a class of multiple input power converters, used to manage hybrid electrical energy sources. The third part regards adaptive observers design for robust estimation of the parameters required for high performance control of power systems.

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Atmosphärische Aerosole beeinflussen den Strahlungshaushalt und damit das Klima der Erde. Dies geschieht sowohl direkt (Streuung und Absorption), als auch indirekt (Wolkenkondensationskeime). Das sekundäre organische Aerosol (SOA) bildet einen wichtigen Bestandteil des atmosphärischen Aerosols. Seine Bildung erfolgt durch Reaktionen von Kohlenwasserstoffen mit atmosphärischen Oxidationsmitteln (z.B. Ozon, OH-Radikalen). Eine Klasse dieser Kohlenwasserstoffe sind die Terpene. Sie werden in großen Mengen durch die Vegetation emittiert und gelten als wichtige Vorläufersubstanzen des biogenen SOAs. In den Reaktionen von Monoterpenen und Sesquiterpenen mit atmosphärischen Reaktionspartnern wird eine große Vielfalt an multifunktionellen Reaktionsprodukten gebildet, von denen bis heute nur ein Bruchteil identifiziert werden konnte. In der vorliegenden Arbeit soll im Speziellen die Bildung von organischen Peroxiden und oligomeren Verbindungen im biogenen SOA untersucht und Nachweise einzelner Moleküle erbracht werden.rnFür eine Identifizierung von organischen Peroxiden aus der Oxidation einzelner Monoterpene und Sesquiterpene mit Ozon wurden die Reaktionsprodukte direkt in eine bei Atmosphärendruck arbeitende chemische Ionisationsquelle überführt und massenspektrometrisch untersucht (online-APCI-MS). Hierdurch konnten organische Hydroperoxide in der Partikelphase nachgewiesen werden, welche sich durch eine signifikante Abspaltung von H2O2 im Tandem-Massenspektrum (MS/MS) auszeichneten. Des Weiteren sollte die Bildung von höhermolekularen Verbindungen („Dimere“) im SOA des α-Pinens untersucht werden. Hierfür wurden zunächst die Reaktionsprodukte des Cyclohexens, das als einfache Modellverbindung des α-Pinens dient, mittels online-APCI-MS und offline durch Flüssigkeitschromatographie und Elektrospray-Ionenfallenmassenspektrometrie (HPLC/ESI-MS) untersucht. Verschiedene Produkte der Cyclohexen-Ozonolyse konnten hierbei als Esterverbindungen identifiziert werden, wobei eigens synthetisierte Referenzsubstanzen für die Identifizierung verwendet wurden. In einem weiteren Experiment, indem gleichzeitig Cyclohexen und α-Pinen mit Ozon umgesetzt wurden, konnten ebenfalls eine Bildung von höhermolekularen Estern nachgewiesen werden. Es handelte sich hierbei um „Mischester“, deren Struktur aus Reaktionsprodukten der beiden VOC-Vorläufermoleküle aufgebaut war. Durch diese neuen Erkenntnisse, über die Bildung von Estern im SOA des Cyclohexens, wurden die Dimer-Bildung einer reinen α-Pinen/Ozon-Reaktion online und offline massenspektrometrisch untersucht. Hier stellten sich als Hauptprodukte die Verbindungen mit m/z 357 und m/z 367 ([M-H]--Ionen) heraus, welche zudem erstmals auf einem Filter einer Realprobe aus Hyytiälä, Finnland nachgewiesen werden konnten. Aufgrund ihrer Fragmentierung in MS/MS-Untersuchungen sowie den exakten Summenformeln aus FT-MS Messungen konnte für die Struktur der höhermolekularen Verbindung mit m/z 367 ebenfalls ein Ester und für m/z 357 ein Peroxyhemiacetal vorgeschlagen werden. Die vorgeschlagene Struktur der Verbindung m/z 367 konnte im Anschluss über eine Reaktion aus Hydroxypinonsäure mit Pinsäure bestätigt werden. Die Identifizierung der Esterverbindung des α-Pinen-SOA erfolgte ebenfalls mit Hilfe von LC-MSn-Messungen.rnDie bisher diskutierten Ergebnisse, sowie die meisten in der Literatur beschriebenen Studien befassen sich jedoch mit einzelnen Vorläuferverbindungen, im Gegensatz zu den komplexen SOA-Proben aus den Emissionen der Vegetation. Im Rahmen einer Messkampagne am Forschungszentrum Jülich erfolgte eine massenspektrometrische Charakterisierung (online-APCI-MS) des SOAs aus direkten VOC-Emissionen von Pflanzen. Durch einen Vergleich der Produktverteilung dieser erhalten online-Massenspektren mit denen aus den Reaktionen einzelner VOCs, konnten Aussagen über die in den Reaktionen umgesetzten VOCs gemacht werden. Es konnte gezeigt werden, dass in stressbedingten Situationen die untersuchten Exemplare der Betula pendula (Birke) hauptsächlich Sesquiterpene, Picea abies (Fichte) eher Monoterpene und Eucalyptus (Eukalyptus) sowohl Sesquiterpene als auch Monoterpene emittieren. Um die atmosphärischen Prozesse, die zur Bildung der Produkte im SOA führen vollständig zu verstehen, müssen jedoch noch weitere Anstrengungen unternommen werden.rn

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The present study was conducted to investigate the influence of restricted food access on Solea senegalensis behaviour and daily expression of clock genes in central (diencephalon and optic tectum) and pheripheral (liver) tissues. The Senegalese sole is a marine teleost fish belonging to the Class of Actinopterygii, Order Pleuronectiformes and Family Soleidae. Its geographical distribution in the Mediterranean sea is fairly broad, covering the south and east of the Iberian Peninsula, the North of Africa and Middle East until the coast of Turkey. From a commercial perspective Solea senegalensis has acquired in recent years, a key role in aquacolture industry of the Iberian Peninsula. The Senegalese sole is also acquiring an important relevance in chronobiological studies as the number of published works focused on the sole circadian system has increased in the last few years. The molecular mechanisms underlying sole circadian rhythms has also been explored recently, both in adults and developing sole. Moreover, the consideration of the Pleuronectiformes Order as one of the most evolved teleost groups make the Senegalese sole a species of high interest under a comparative and phylogenetic point of view. All these facts have reinforced the election of Senegalese sole as model species for the present study. The animals were kept under 12L:12D photoperiod conditions and divided into three experimental groups depending on the feeding time: fed at midlight (ML), middark (MD) or random (RND) times. Throughout the experiment, the existence of a daily activity rhythm and it synchronization to the light-dark and feeding cycles was checked. To this end locomotor activity was registred by means of two infrared photocells placed in pvc tube 10 cm below the water surface (upper photocell) and the other one was located 10 cm above the bottom of the tank (bottom photocell). The photocell were connected to a computer so that every time a fish interrupted the infrared light beam, it produced an output signal that was recorded. The number of light beam interruptions was stored every 10 minutes by specialized software for data acquisition.

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La ricerca riguarda lo studio del cantiere edilizio protobizantino, con particolare riferimento al ciclo della lavorazione del marmo. Quest’ultimo viene analizzato sotto il profilo amministrativo, tecnico, sociale ed artigianale. L’elemento guida della ricerca sono i marchi dei marmorari, sigle apposte da funzionari e maestranze durante il processo produttivo. Dapprima, fonti letterarie ed epigrafiche, tra cui le sigle di cava e officina su marmo, vengono esaminate per ricostruire il sistema alto-imperiale di amministrazione delle cave e di gestione dei flussi marmorei, nonché l’iter tecnico-artigianale adottato per la produzione dei manufatti. Il confronto con i dati disponibili per la tarda antichità, con particolare riferimento alle cave di Proconneso, evidenzia una sostanziale continuità della prassi burocratico-amministrativa, mentre alcuni cambiamenti si riscontrano nell’ambito produttivo-artigianale. Il funzionamento degli atelier marmorari viene approfondito attraverso lo studio dei marchi dei marmorari. Si tratta di caratteri greci singoli, multipli o monogrammi. Una ricognizione sistematica delle sigle dalla pars Orientalis dell’impero, reperite in bibliografia o da ricognizioni autoptiche, ha portato alla raccolta di circa 2360 attestazioni. Per esse si propone una classificazione tipologica tra sigle di cava, stoccaggio, officina. Tra le sigle di cava si annoverano sigle di controllo, destinazione/committenza, assemblaggio/posizionamento. Una particolare attenzione è riservata alle sigle di officina, riferibili ad un nome proprio di persona, ovvero al πρωτομαΐστωρ, il capo-bottega che supervisionava il lavoro dei propri artigiani e fungeva da garante del prodotto consegnato alla committenza. Attraverso lo studio comparato delle sigle reperite a Costantinopoli e in altri contesti si mette in luce la prassi operativa adottata dagli atelier nei processi di manifattura, affrontando anche il problema delle maestranze itineranti. Infine, sono analizzate fonti scritte di varia natura per poter collocare il fenomeno del marmo in un contesto socio-economico più ampio, con particolare riferimento alle figure professionali ed artigianali coinvolte nei cantieri e al problema della committenza.

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9-hydroxystearic acid (9-HSA) belongs to a class of lipid peroxidation products identified in several human and murine cell lines. These products are greatly diminished in tumors compared to normal tissues and their amount is inversely correlated with the malignancy of the tumor. 9-HSA activity has been tested in cancer cell lines, where it showed to act as a histone deacetylase 1 (HDAC1) inhibitor. In particular, in a colon cancer cell line (HT29), its administration resulted in an inhibition of proliferation together with an induction of differentiation. In this thesis the effect of (R)-9-hydroxystearic acid has been tested in vivo on cell proliferation and differentiation processes, in the early stages of zebrafish development. The final aim of this work was to elucidate the role of (R)-9-HSA in the control of cell differentiation and proliferation during normal development, in order to better understand its molecular control of cancerogenesis. The molecule has been administered via injection in the yolk of zebrafish embryos. The analysis of the histone acetylation pattern showed a hyperacetilation of histone H4 after treatment with the molecule, as detectable in HDAC1 mutants. (R)-9-HSA was also demonstrated to interfere with the signaling pathways that regulate proliferation and differentiation in zebrafish retina and hindbrain. This resulted in a reduction of proliferation in the hindbrain at 24 hours post injection (hpi), and in a hyperproliferation at 48 and 72 hpi in the retina, with a concomitant inhibition of differentiation. Finally, (R)-9-HSA effects were evident on proliferation of stem cell located in the ciliary marginal zone (CMZ) of the retina. The presence of ROS and 4-hydroxynoneal in the CMZ of wild-type embryos supports the hypothesis that oxidative stress could regulate stem cells fate in zebrafish retina.

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The research work has dealt with the study of new catalytic processes for the synthesis of fine chemicals belonging to the class of phenolics, namely 2-phenoxyethanol and hydroxytyrosol. The two synthetic procedures investigated have the advantages of being much closer to the Green Chemistry principles than those currently used industrially. In both cases, the challenge was that of finding catalysts and methods which led to the production of less waste, and used less hazardous chemicals, safer solvents, and reusable heterogeneous catalysts. In the case of 2-phenoxyethanol, the process investigated involves the use of ethylene carbonate (EC) as the reactant for phenol O-hydroxyethylation, in place of ethylene oxide. Besides being a safer reactant, the major advantage of using EC in the new synthesis is the better selectivity to the desired product achieved. Moreover, the solid catalyst based on Na-mordenite was fully recyclable. The reaction mechanism and the effect of the Si/Al ratio in the mordenite were investigated. In the case of hydroxytyrosol, which is one of the most powerful natural antioxidants, a new synthetic procedure was investigated; in fact, the method currently employed, the hydrolysis of oleuropein, an ester extracted from the waste water processing of the olive, makes use of large amounts of organic solvents (hexane, ethyl acetate), and involves several expensive steps of purification. The synthesis procedure set up involves first the reaction between catechol and 2,2-dimethoxyacetaldehyde, followed by the one-pot reduction of the intermediate to give the desired product. Both steps were optimized, in terms of catalyst used, and of reaction conditions, that allowed to reach ca 70% yield in each step. The reaction mechanism was investigated and elucidated. During a 3-month period spent at the University of Valencia (with Prof. A. Corma’s group), a process for the production of diesel additives (2,5-bis(propoxymethyl)furan) from fructose has been investigated.

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SUMOylation is a highly dynamic and reversible posttranslational protein modification closely related to ubiquitination. SUMOylation regulates a vast array of different cellular functions, such as cell cycle, nuclear transport, DNA damage response, proliferation and transcriptional activation. Several groups have shown in in vitro studies how important SUMOylation is for early B cell development and survival as well as for later plasma cell differentiation. This thesis focuses on the deSUMOylation protease SENP1 and its in vivo effects on B cell development and differentiation. For this a conditional SENP1 knockout mouse model was crossed to the CD19-Cre mouse strain to generate a B cell specific SENP1 knockout mouse.rnIn our conditional SENP1ff CD19-Cre mouse model we observed normal numbers of all B cell subsets in the bone marrow. However in the spleen we observed an impairment of B cell survival, based on a 50% reduction of the follicular B cell compartment, whereas the marginal zone B cell compartment was unchanged. T cell numbers were comparable to control mice. rnFurther, impairments of B cell survival in SENP1ff CD19-Cre mice were analysed after in vivo blocking of IL7R signalling. The αIL7R treatment in mature mice blocked new B cell formation in the bone marrow and increased apoptosis rates could be observed in splenic SENP1 KO B cells. Additionally, a higher turnover rate of B cells was measured by in vivo BrdU incorporation.rnSince it is known that the majority of transcription factors that are important for the maintenance of the germinal centre reaction or for induction of plasma cell development are SUMOylated, the question arose, how defective deSUMOylation will manifest itself in these processes. The majority of in vitro cultured splenic B cells, stimulated to undergo class switch recombination and plasma cell differentiation underwent activation induced cell death. However, the surviving cells increasingly differentiated into IgM expressing plasma cells. Class switch recombination to IgG1 was reduced. These observations stood in line with observation made in in vivo sheep red blood cell immunization experiments, which showed increased amounts of germinal centres and germinal centre B cells, as well as increased amounts of plasma cells differentiation in combination with decreased class switch to IgG1.rnThese results lead to the conclusion that SENP1 KO B cells increasingly undergo apoptosis, however, B cells that survive SENP1 deficiency are more prone to undergo plasma cell differentiation. Further, the precursors of these plasma cells either are not as capable of undergoing class switch recombination or they do switch to IgG1 and succumb to activation induced cell death. One possible explanation for both scenarios could be a defective DNA damage response mechanisms during class switch recombination, caused by impaired deSUMOylation. rn

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The interest of the scientific community towards organic pollutants in freshwater streams is fairly recent. During the past 50 years, thousands of chemicals have been synthesized and released into the general environment. Nowadays their occurrence and effects on several organism, invertebrates, fish, birds, reptiles and also humans are well documented. Because of their action, some of these chemicals have been defined as Endocrine Disrupters Compounds (EDCs) and the public health implications of these EDCs have been the subject of scientific debate. Most interestingly, among those that were noticed to have some influence and effects on the endocrine system were the estrone, the 17β-estradiol, the 17α-estradiol, the estriol, the 17α-ethinylestradiol, the testosterone and the progesterone. This project focused its attention on the 17β-estradiol. Estradiol, or more precisely, 17β-estradiol (also commonly referred to as E2) is a human sex hormone. It belongs to the class of steroid hormones. In spite of the effort to remove these substances from the effluents, the actual wastewater treatment plants are not able to degrade or inactivate these organic compounds that are continually poured in the ecosystem. Through this work a new system for the wastewater treatment was tested, to assess the decrease of the estradiol in the water. It involved the action of Chlorella vulgaris, a fresh water green microalga belonging to the family of the Chlorellaceae. This microorganism was selected for its adaptability and for its photosynthetic efficiency. To detect the decrease of the target compound in the water a CALUX bioassay analysis was chosen. Three different experiments were carried on to pursue the aim of the project. By analysing their results several aspects emerged. It was assessed the presence of EDCs inside the water used to prepare the culture media. C. vulgaris, under controlled conditions, could be efficient for this purpose, although further researches are essential to deepen the knowledge of this complex phenomenon. Ultimately by assessing the toxicity of the effluent against C. vulgaris, it was clear that at determined concentrations, it could affect the normal growth rate of this microorganism.

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Sir, anti TNF-α agents (aTNFs) are the most commonly prescribed biological agents in RA. More recently abatacept (ABA), a T-cell costimulation modulator, and rituximab (RTX), a monoclonal antibody directed against CD20, have become available. Observational studies suggest that switching to a new drug class may be more effective in uncontrolled RA than switching to a class of biologics to which the patient had unsuccessfully been exposed [1]. Information about the efficacy and safety of cycling strategies through third-line biologics is lacking. This study aimed to analyse the effectiveness and safety of switching patients to ABA as the third biological class after failure of aTNF plus RTX. The Swiss Clinical Quality Management (SCQM) programme for RA is a longitudinal population-based cohort, which has been approved by the local ethics committees of all participating centres [2]. For this analysis, we collected all the …

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The purpose of this study was to investigate the questioning strategies of preservice teachers whenteaching science as inquiry. The guiding questions for this research were: In what ways do the questioning strategies of preservice teachers differ for male and female elementary students when teaching science as inquiry and how is Bloom’s Taxonomy evident within the questioning strategies of preservice teachers? Examination of the data indicated that participants asked a total of 4,158 questions to their elementary aged students. Of these questions, 974 (23%) were asked to boys, and 991 (24%) were asked to girls. The remaining questions (53%) were asked to the class as a whole, therefore no gender could be assigned to these questions. In relation to Bloom’s Taxonomy, 74% of the questions were basic knowledge, 15% were secondary comprehension, 2% were application, 4% were analysis, 1% were synthesis, and 3% were evaluation.

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New tetracycline and streptomycin resistance genes, tet(44) and ant(6)-Ib, were identified in Campylobacter fetus subsp. fetus within a transferable pathogenicity island that is typically unique to Campylobacter fetus subsp. venerealis. The 640-amino-acid tetracycline resistance determinant, Tet 44, belongs to a class of proteins that confers resistance to tetracycline and minocycline by ribosomal protection. The 286-amino-acid streptomycin resistance determinant, ANT(6)-Ib, belongs to a family of aminoglycoside nucleotidyltransferases. The resistance phenotypes were demonstrated by gene inactivation and expression.

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Hyperkalemia is a concern in heart failure (HF), especially in older patients with co-morbidities. Previous studies addressing this issue have focused mainly on younger patients. This study was aimed at determining the frequency and predictors of hyperkalemia in older patients with HF undergoing intense medical therapy. Frequency and predictors of hyperkalemia were defined in patients (n = 566) participating in the Trial of Intensified versus Standard Medical Therapy in Elderly Patients with Congestive Heart Failure, in which patients ≥60 years of age were randomized to a standard versus an intensified N-terminal brain natriuretic peptide-guided HF therapy. During an 18-month follow-up 76 patients (13.4%) had hyperkalemia (≥5.5 mmol/L) and 28 (4.9%) had severe hyperkalemia (≥6.0 mmol/L). Higher baseline serum potassium (odds ratio [OR] 2.92 per mmol/L), baseline creatinine (OR 1.11 per 10 μmol/L), gout (OR 2.56), New York Heart Association (NYHA) class (compared to NYHA class II, IV OR 3.08), higher dosage of spironolactone at baseline (OR 1.20 per 12.5 mg/day), and higher dose changes of spironolactone (compared to no dose change: 12.5 mg, OR 1.45; 25 mg, OR 2.52; >25 mg, OR 3.24) were independent predictors for development of hyperkalemia (p <0.05 for all comparisons). In conclusion, hyperkalemia is common in patients ≥60 years of age with HF undergoing intense medical therapy. Risk is increased in patients treated with spironolactone, in addition to patient-specific risk factors such as chronic kidney disease, higher serum potassium, advanced NYHA class, and gout. Careful surveillance of serum potassium and cautious use of spironolactone in patients at risk may help to decrease the incidence of potentially hazardous complications caused by hyperkalemia.

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The discourse on sexuality in nineteenth-century Spain presents a fundamental difference between the masculine ideal of that period and our current definition of masculinity. According to today’s popular stereotype, the typical man seeks out sexual contact and takes any opportunities that arise. By contrast, within the hygiene texts of the nineteenth century one detects a sense of unease associated with sexual activity and its corresponding role in the construction of hegemonic masculinity. In particular, sexual excess, masturbation, and celibacy were viewed as antagonistic to middle-class masculinity, which was instead associated with venereal moderation, marriage, and fatherhood. Men who transgressed this model risked their health as well as their masculinity. This formula reveals an element of fragility with regard to notions of manhood, in contrast to the traditional image of Spanish masculinity that originated during the Reconquest and is based on bellicose heroism, bravado, and sexual prowess.

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The Hungarian way of decoration has certain characteristics which are rooted in the deep symbolism of ancient Hungarian mythical thinking. The ancient heritage of the Hungarians' former homeland somewhere in the Urals included eastern elements. During their migrations, the Hungarian tribes met other eastern peoples and their culture of decoration became mixed with elements drawn from these new contacts. These diverse influences mean that the Hungarian way of thinking, building and ornamentation show a certain dualism of Puritanism and rationalism in the creation of space and manufacturing, and rich fantasy in decoration and ornamentation. The Hungarians use coloured ornamentation to emphasise the symbolic importance of details. The colouring system of the built environment shows the same dualism: the main colour of the facades and inner walls is white, while the furniture, textiles, gates and windows, and sometimes the gable and fireplace are richly decorated. In Hungarian symbolism, the house and settlement are a model of the universe, so their different parts also have a transcendent meaning. The traditional meanings of the different colours reflect this transcendence. Each colour has ambivalent meanings: RED - the colour of blood - means violence and love. YELLOW - means sickness, death and ripeness (golden yellow). BLUE - means innocence, eternity (light blue) and old age, death (dark blue). BLACK - can be both ceremonial and mourning. WHILE - can have sacred meaning (bright white), while yellowish white fabric is the most common garb of both men and women in village society. GREEN - the only colour without a dual meaning, symbolises the beginning of life. Until the late 18th and early 19th centuries Hungarian folk art used one or two-coloured decoration (red, black, blue, red-blue or red-black), and from the early 19th century it moved to multi-coloured decoration. Colours are characteristically used in complementary contrast, with bright colours on a plain ground and an avoidance of subtle shadings.