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DNA methylation, through 5-methyl- and 5-hydroxymethylcytosine (5mC and 5hmC) is considered to be one of the principal interfaces between the genome and our environment and it helps explain phenotypic variations in human populations. Initial reports of large differences in methylation level in genomic regulatory regions, coupled with clear gene expression data in both imprinted genes and malignant diseases provided easily dissected molecular mechanisms for switching genes on or off. However, a more subtle process is becoming evident, where small (<10%) changes to intermediate methylation levels were associated with complex disease phenotypes. This has resulted in two clear methylation paradigms. The latter "subtle change" paradigm is rapidly becoming the epigenetic hallmark of complex disease phenotypes, although we were currently hampered by a lack of data addressing the true biological significance and meaning of these small differences. The initial expectation of rapidly identifying mechanisms linking environmental exposure to a disease phenotype led to numerous observational/association studies being performed. Although this expectation remains unmet, there is now a growing body of literature on specific genes, suggesting wide ranging transcriptional and translational consequences of such subtle methylation changes. Data from the glucocorticoid receptor (NR3C1) has shown that a complex interplay between DNA methylation, extensive 5"UTR splicing and microvariability gives rise to the overall level and relative distribution of total and N-terminal protein isoforms generated. Additionally, the presence of multiple AUG translation initiation codons throughout the complete, processed, mRNA enables translation variability, hereby enhancing the translational isoforms and the resulting protein isoform diversity; providing a clear link between small changes in DNA methylation and significant changes in protein isoforms and cellular locations. Methylation changes in the NR3C1 CpG island, alters the NR3C1 transcription and eventually protein isoforms in the tissues, resulting in subtle but visible physiological variability. Implying external environmental stimuli act through subtle methylation changes, with transcriptional microvariability as the underlying mechanism, to fine-tune the total NR3C1 protein levels. The ubiquitous distribution of genes with similar structure as NR3C1, combined with an increasing number of studies linking subtle methylation changes in specific genes with wide ranging transcriptional and translational consequences, suggested a more genome-wide spread of subtle DNA methylation changes and transcription variability. The subtle methylation paradigm and the biological relevance of such changes were supported by two epigenetic animal models, which linked small methylation changes to either psychopathological or immunological effects. The first model, rats subjected to maternal deprivation, showed long term behavioural and stress response changes. A second model, exposing mice to early life infection with H1N1, illustrated long-term immunological effects. Both models displayed subtle changes within the methylome. Suggesting/Indicating that early life adversity and early life viral infection "programmed" the CNS and innate immune response respectively, via subtle DNA methylation changes genome-wide. The research presented in this thesis investigated the ever-growing roles of DNA methylation; the physiological and functional relevance of subtle small DNA methylation changes genome-wide, in particular for the CNS (MD model) and the immune system (early life viral infection model) ; and the evidence available, particularly from the glucocorticoid of the cascade of events initiated by such subtle methylation changes, as well as addressing the underlying question as to what represents a genuine biologically significant difference in methylation.
This study aims to estimate the cotton yield at the field and regional level via the APSIM/OZCOT crop model, using an optimization-based recalibration approach based on the state variable of the cotton canopy - the leaf area index (LAI), derived from atmospherically corrected Landsat-8 OLI remote sensing images in 2014. First, a local sensitivity and global analysis approach was employed to test the sensitivity of cultivar, soil and agronomic parameters to the dynamics of the LAI. After sensitivity analyses, a series of sensitive parameters were obtained. Then, the APSIM/OZCOT crop model was calibrated by observations over a two-year span (2006-2007) at the Aksu station, combined with these sensitive cultivar parameters and the current understanding of cotton cultivar parameters. Third, the relationship between the observed in-situ LAI and synchronous perpendicular vegetation indices derived from six Landsat-8 OLI images covering the entire growth stage was modelled to generate LAI maps in time and space. Finally, the Particle Swarm Optimization (PSO) and general-purpose optimization approach (based on Nelder-Mead algorithm) were used to recalibrate four sensitive agronomic parameters (row spacing, sowing density per row, irrigation amount and total fertilization) according to the minimization of the root-mean-square deviation (RMSE) between the simulated LAI from the APSIM/OZCOT model and retrieved LAI from Landsat-8 OLI remote sensing images. After the recalibration, the best simulated results compared with observed cotton yield were obtained. The results showed that: (1) FRUDD, FLAI and DDISQ were the major cultivar parameters suitable for calibrating the cotton cultivar. (2) After the calibration, the simulated LAI performed well with an RMSE and mean absolute error (MAE) of 0.45 and 0.33, respectively, in 2006 and 0.46 and 0.41, respectively, in 2007. The coefficient of determination between the observed and simulated LAI was 0.83 and 0.97, respectively, in 2006 and 2007. The Pearson- correlation coefficient was 0.913 and 0.988 in 2006 and 2007, respectively, with a significant positive correlation between the simulated and observed LAI. The difference between the observed and simulated yield was 776.72 kg/ha and 259.98 kg/ha in 2006 and 2007, respectively. (3) Cotton cultivation in 2014 was obtained using three Landsat-8 OLI images - DOY136 (May), DOY 168 (June) and DOY 200 (July) - based on the phenological differences in cotton and other vegetation types. (4) The yield estimation after the assimilation closely approximated the field-observed values, and the coefficient of determination was as high as 0.82, after recalibration of the APSIM/OZCOT model for ten cotton fields. The difference between the observed and assimilated yields for the ten fields ranged from 18.2 to 939.7 kg/ha. The RMSE and MAE between the assimilated and observed yield was 417.5 and 303.1 kg/ha, respectively. These findings provide scientific evidence for the feasibility of coupled remote sensing and APSIM/OZCOT model at the field level. (5) Upscaling from field level to regional level, the assimilation algorithm and scheme are both especially important. Although the PSO method is very efficient, the computational efficiency is also the shortcoming of the assimilation strategy on a regional scale. Comparisons between the PSO and general-purpose optimization method (based on the Nelder-Mead algorithm) were implemented from the RSME, LAI curve and computational time. The general-purpose optimization method (based on the Nelder-Mead algorithm) was used for the regional assimilation between remote sensing and the APSIM/OZCOT model. Meanwhile, the basic unit for regional assimilation was also determined as cotton field rather than pixel. Moreover, the crop growth simulation was also divided into two phases (vegetative growth and reproductive growth) for regional assimilation. (6) The regional assimilation at the vegetative growth stage between the remote sensing derived and APSIM/OZCOT model-simulated LAI was implemented by adjusting two parameters: row spacing and sowing density per row. The results showed that the sowing density of cotton was higher in the southern part than in the northern part of the study area. The spatial pattern of cotton density was also consistent with the reclamation from 2001 to 2013. Cotton fields after early reclamation were mainly located in the southern part while the recent reclamation was located in the northern part. Poor soil quality, lack of irrigation facilities and woodland belts of cotton fields in the northern part caused the low density of cotton. Regarding the row spacing, the northern part was larger than the southern part due to the variation of two agronomic modes from military and private companies. (7) The irrigation and fertilization amount were both used as key parameters to be adjusted for regional assimilation during the reproductive growth period. The result showed that the irrigation per time ranged from 58.14 to 89.99 mm in the study area. The spatial distribution of the irrigation amount is higher in the northern part while lower in southern study area. The application of urea fertilization ranged from 500.35 to 1598.59 kg/ha in the study area. The spatial distribution of fertilization was lower in the northern part and higher in the southern part. More fertilization applied in the southern study area aims to increase the boll weight and number for pursuing higher yields of cotton. The frequency of the RSME during the second assimilation was mainly located in the range of 0.4-0.6 m2/m2. The estimated cotton yield ranged from 1489 to 8895 kg/ha. The spatial distribution of the estimated yield is also higher in the southern part than the northern study area.
Flexibility and spatial mobility of labour are central characteristics of modern societies which contribute not only to higher overall economic growth but also to a reduction of interregional employment disparities. For these reasons, there is the political will in many countries to expand labour market areas, resulting especially in an overall increase in commuting. The picture of the various, unintended long-term consequences of commuting on individuals is, however, relatively unclear. Therefore, in recent years, the journey to work has gained high attention especially in the study of health and well-being. Empirical analyses based on longitudinal as well as European data on how commuting may affect health and well-being are nevertheless rare. The principle aim of this thesis is, thus, to address this question with regard to Germany using data from the Socio-Economic Panel. Chapter 2 empirically investigates the causal impact of commuting on absence from work due to sickness-related reasons. Whereas an exogenous change in commuting distance does not affect the number of absence days of those individuals who commute short distances to work, it increases the number of absence days of those employees who commute middle (25 " 49 kilometres) or long distances (50 kilometres and more). Moreover, our results highlight that commuting may deteriorate an individual- health. However, this effect is not sufficient to explain the observed impact of commuting on absence from work. Chapter 3 explores the relationship between commuting distance and height-adjusted weight and sheds some light on the mechanisms through which commuting might affect individual body weight. We find no evidence that commuting leads to excess weight. Compensating health behaviour of commuters, especially healthy dietary habits, could explain the non-relationship of commuting and height-adjusted weight. In Chapter 4, a multivariate probit approach is used to estimate recursive systems of equations for commuting and health-related behaviours. Controlling for potential endogeneity of commuting, the results show that long distance commutes significantly decrease the propensity to engage in health-related activities. Furthermore, unobservable individual heterogeneity can influence both the decision to commute and healthy lifestyle choices. Chapter 5 investigates the relationship between commuting and several cognitive and affective components of subjective well-being. The results suggest that commuting is related to lower levels of satisfaction with family life and leisure time which can largely be ascribed to changes in daily time use patterns, influenced by the work commute.
Die organische Bodensubstanz (OBS) ist eine fundamentale Steuergröße aller biogeochemischen Prozesse und steht in engem Zusammenhang zu Kohlenstoffkreisläufen und globalem Klima. Die derzeitige Herausforderung der Ökosystemforschung ist die Identifizierung der für die Bodenqualität relevanten Bioindikatoren und deren Erfassung mit Methoden, die eine nachhaltige Nutzung der OBS in großem Maßstab überwachen und damit zu globalen Erderkundungsprogrammen beitragen können. Die fernerkundliche Technik der Vis-NIR Spektroskopie ist eine bewährte Methode für die Beurteilung und das Monitoring von Böden, wobei ihr Potential bezüglich der Erfassung biologischer und mikrobieller Bodenparameter bisher umstritten ist. Das Ziel der vorgestellten Arbeit war die quantitative und qualitative Untersuchung der OBS von Ackeroberböden mit unterschiedlichen Methoden und variierender raumzeitlicher Auflösung sowie die anschließende Bewertung des Potentials non-invasiver, spektroskopischer Methoden zur Erfassung ausgewählter Parameter dieser OBS. Dafür wurde zunächst eine umfassende lokale Datenbank aus chemischen, physikalischen und biologischen Bodenparametern und dazugehörigen Bodenspektren einer sehr heterogenen geologischen Region mit gemäßigten Klima im Südwesten Deutschlands erstellt. Auf dieser Grundlage wurde dann das Potential der Bodenspektroskopie zur Erfassung und Schätzung von Feld- und Geländedaten ausgewählter OBS Parameter untersucht. Zusätzlich wurde das Optimierungspotential der Vorhersagemodelle durch statistische Vorverarbeitung der spektralen Daten getestet. Die Güte der Vorhersagewahrscheinlichkeit gebräuchlicher fernerkundlicher Bodenparameter (OC, N) konnte für im Labor erhobene Hyperspektralmessungen durch statistische Optimierungstechniken wie Variablenselektion und Wavelet-Transformation verbessert werden. Ein zusätzliches Datenset mit mikrobiellen/labilen OBS Parametern und Felddaten wurde untersucht um zu beurteilen, ob Bodenspektren zur Vorhersage genutzt werden können. Hierzu wurden mikrobieller Kohlenstoff (MBC), gelöster organischer Kohlenstoff (DOC), heißwasserlöslicher Kohlenstoff (HWEC), Chlorophyll α (Chl α) und Phospholipid-Fettsäuren (PLFAs) herangezogen. Für MBC und DOC konnte abhängig von Tiefe und Jahreszeit eine mittlere Güte der Vorhersagewahrscheinlichkeit erreicht werden, wobei zwischen hohen und niedrigen Konzentration unterschieden werden konnte. Vorhersagen für OC und PLFAs (Gesamt-PLFA-Gehalt sowie die mikrobiellen Gruppen der Bakterien, Pilze und Algen) waren nicht möglich. Die beste Prognosewahrscheinlichkeit konnte für das Chlorophyll der Grünalgen an der Bodenoberfläche (0-1cm Bodentiefe) erzielt werden, welches durch Korrelation mit MBC vermutlich auch für dessen gute Vorhersagewahrscheinlichkeit verantwortlich war. Schätzungen des Gesamtgehaltes der OBS, abgeleitet durch OC, waren hingegen nicht möglich, was der hohen Dynamik der mikrobiellen OBS Parameter an der Bodenoberfläche zuzuschreiben ist. Das schränkt die Repräsentativität der spektralen Messung der Bodenoberfläche zeitlich ein. Die statistische Optimierungstechnik der Variablenselektion konnte für die Felddaten nur zu einer geringen Verbesserung der Vorhersagemodelle führen. Die Untersuchung zur Herkunft der organischen Bestandteile und ihrer Auswirkungen auf die Quantität und Qualität der OBS konnte die mikrobielle Nekromasse und die Gruppe der Bodenalgen als zwei mögliche weitere signifikante Quellen für die Entstehung und Beständigkeit der OBS identifizieren. Insgesamt wird der mikrobielle Beitrag zur OBS höher als gemeinhin angenommen eingestuft. Der Einfluss mikrobieller Bestandteile konnte für die OBS Menge, speziell in der mineralassoziierten Fraktion der OBS in Ackeroberböden, sowie für die OBS Qualität hinsichtlich der Korrelation von mikrobiellen Kohlenhydraten und OBS Stabilität gezeigt werden. Die genaue Quantifizierung dieser OBS Parameter und ihre Bedeutung für die OBS Dynamik sowie ihre Prognostizierbarkeit mittels spektroskopischer Methoden ist noch nicht vollständig geklärt. Für eine abschließende Beurteilung sind deshalb weitere Studien notwendig.
Erosion durch Regen und Wind schädigt fruchtbare Bodensubstanz irreversibel, verursacht weltweit riesige ökologische und sozio-ökonomische Schäden und ist eines der Hauptanliegen bezüglich Ökosystemdienstleistungen und Nahrungsmittelsicherheit. Die Quantifizierung von Abtragsraten ist immer noch höchst spekulativ, und fehlende empirische Daten führen zu großen Unsicherheiten von Risikoanalysemodellen. Als ein wesentlicher Grund für diese Unsicherheiten wird in dieser Arbeit die Prozesse der Beeinflussung von Wassererosion durch Wind und, im Speziellen, die Erosionsleistung von windbeeinflussten Regentropfen im Gegensatz zu windlosen Tropfen inklusive unterschiedlicher Oberflächenparameter beleuchtet. Der Forschungsansatz war experimentell-empirisch und beinhaltete die Entwicklung und Formulierung der Forschungshypothesen, die Konzeption und Durchführung von Experimenten mit einem mobilen Wind-Regenkanal, die Probenverarbeitung und Analyse sowie Interpretation der Daten. Die Arbeit gliedert sich in die Teile 1. "Bodenerosionsexperimente zu windbeeinflusstem Regen auf autochthonen und naturähnlichen Böden", 2. "Experimente zu Substratpartikeltransport durch windbeeinflussten Tropfenschlag" und 3. "Zusammenführung der Freiland- und Labortests". 1. Tests auf autochthonen degradierten Böden im semiariden Südspanien sowie auf kohäsionslosem sandigen Substrat wurden durchgeführt, um die relativen Auswirkungen von windbeeinflusstem Regen auf Oberflächenabflussbildung und Erosion zu untersuchen und zu quantifizieren. In der überwiegenden Anzahl der Versuche wurde klar eine Erhöhung der Erosionsraten festgestellt, was die Forschungshypothese, windbeeinflusster Regen sei erosiver als windloser Regen, deutlich bestätigte. Neben den stark erhöhten wurden auch niedrigere Abtragswerte gemessen, was zum einen die ausnehmende Relevanz der Oberflächenstrukturen und damit von in-situ- Experimenten belegte, zum anderen auf eine Erhöhung der Variabilität der Erosionsprozesse deutete. Diese Variabilität scheint zuzunehmen mit der Erhöhung der beteiligten Faktoren. 2. Ein sehr spezialisiertes Versuchsdesign wurde entwickelt und eingesetzt, um explizite Messungen der Tropfenschlagprozesse mit und ohne Windeinfluss durchzuführen. Getestet wurden die Erosionsagenzien Regen, Wind und windbeeinflusster Regen sowie drei Neigungen, drei Rauheiten und zwei Substrate. Alle Messergebnisse zeigten eine klare windinduzierte Erhöhung der Erosion um bis zu zwei Größenordnungen gegenüber windlosem Tropfenschlag und Wind. Windbeeinflusster Regen wird durch die gesteigerte Transportmenge und Weite als wesentlicher Erosionsfaktor bestätigt und ist damit ein Schlüsselparameter bei der Quantifizierung von globaler Bodenerosion, Erstellung von Sedimentbudgets und bei der Erforschung von Connectivity. Die Daten sind von hervorragender Qualität und sowohl für anspruchsvollere Analysemethoden (multivariate Statistik) als auch für Modellierungsansätze geeignet. 3. Eine Synthese aus Feld- und Laborversuchen (darunter auch ein bis dato unveröffentlichtes Versuchsset) inklusive einer statistischen Analyse bestätigt WDR als den herausragenden Faktor, der alle anderen Faktoren überlagert. Die Zusammenführung der beiden komplementären Experimentgruppen bringt die Forschungsreihe zu windbeeinflusstem Regen auf eine weiterführende Ebene, indem die Messergebnisse in einen ökologischen Zusammenhang gesetzt werden. Eine vorsichtige Projektion auf Landschaftsebene ermöglicht einen Einblick in die Risikobewertung von Bodenerosion durch windbeeinflussten Regen. Es wird deutlich, dass er sich gerade auch im Zusammenhang mit den durch den Klimawandel verstärkt auftretenden Regensturmereignissen katastrophal auf Bodenerosionsraten auszuwirken kann und dringend in die Bodenerosionsmodellierung integriert werden muss.
This dissertation details how Zeami (ca. 1363 - ca.1443) understood his adoption of the heavenly woman dance within the historical conditions of the Muromachi period. He adopted the dance based on performances by the Ōmi troupe player Inuō in order to expand his own troupe’s repertoire to include a divinely powerful, feminine character. In the first chapter, I show how Zeami, informed by his success as a sexualized child in the service of the political elite (chigo), understood the relationship between performer and audience in gendered terms. In his treatises, he describes how a player must create a complementary relationship between patron and performer (feminine/masculine or yin/yang) that escalates to an ecstasy of successful communication between the two poles, resembling sexual union. Next, I look at how Zeami perceived Inuō’s relationships with patrons, the daimyo Sasaki Dōyo in chapter two and shogun Ashikaga Yoshimitsu in chapter three. Inuō was influenced by Dōyo’s masculine penchant for powerful, awe-inspiring art, but Zeami also recognized that Inuō was able to complement Dōyo’s masculinity with feminine elegance (kakari and yūgen). In his relationship with Yoshimitsu, Inuō used the performance of subversion, both in his public persona and in the aesthetic of his performances, to maintain a rebellious reputation appropriate within the climate of conflict among the martial elite. His play “Aoi no ue” draws on the aristocratic literary tradition of the Genji monogatari, giving Yoshimitsu the role of Prince Genji and confronting him with the consequences of betrayal in the form of a demonic, because jilted, Lady Rokujō. This performance challenged Zeami’s early notion that the extreme masculinity of demons and elegant femininity as exemplified by the aristocracy must be kept separate in character creation. In the fourth chapter, I show how Zeami also combined dominance (masculinity) and submission (femininity) in the corporal capacity of a single player when he adopted the heavenly woman dance. The heavenly woman dance thus complemented not only the masculinity of his male patrons with femininity but also the political power of his patrons with another dominant power, which plays featuring the heavenly woman dance label divine rather than masculine.
This dissertation looked at both design-based and model-based estimation for rare and clustered populations using the idea of the ACS design. The ACS design (Thompson, 2012, p. 319) starts with an initial sample that is selected by a probability sampling method. If any of the selected units meets a pre-specified condition, its neighboring units are added to the sample and observed. If any of the added units meets the pre-specified condition, its neighboring units are further added to the sample and observed. The procedure continues until there are no more units that meet the pre-specified condition. In this dissertation, the pre-specified condition is the detection of at least one animal in a selected unit. In the design-based estimation, three estimators were proposed under three specific design setting. The first design was stratified strip ACS design that is suitable for aerial or ship surveys. This was a case study in estimating population totals of African elephants. In this case, units/quadrant were observed only once during an aerial survey. The Des Raj estimator (Raj, 1956) was modified to obtain an unbiased estimate of the population total. The design was evaluated using simulated data with different levels of rarity and clusteredness. The design was also evaluated on real data of African elephants that was obtained from an aerial census conducted in parts of Kenya and Tanzania in October (dry season) 2013. In this study, the order in which the samples were observed was maintained. Re-ordering the samples by making use of the Murthy's estimator (Murthy, 1957) can produce more efficient estimates. Hence a possible extension of this study. The computation cost resulting from the n! permutations in the Murthy's estimator however, needs to be put into consideration. The second setting was when there exists an auxiliary variable that is negatively correlated with the study variable. The Murthy's estimator (Murthy, 1964) was modified. Situations when the modified estimator is preferable was given both in theory and simulations using simulated and two real data sets. The study variable for the real data sets was the distribution and counts of oryx and wildbeest. This was obtained from an aerial census that was conducted in parts of Kenya and Tanzania in October (dry season) 2013. Temperature was the auxiliary variable for two study variables. Temperature data was obtained from R package raster. The modified estimator provided more efficient estimates with lower bias compared to the original Murthy's estimator (Murthy, 1964). The modified estimator was also more efficient compared to the modified HH and the modified HT estimators of (Thompson, 2012, p. 319). In this study, one auxiliary variable is considered. A fruitful area for future research would be to incorporate multi-auxiliary information at the estimation phase of an ACS design. This could, in principle, be done by using for instance a multivariate extension of the product estimator (Singh, 1967) or by using the generalized regression estimator (Särndal et al., 1992). The third case under design-based estimation, studied the conjoint use of the stopping rule (Gattone and Di Battista, 2011) and the use of the without replacement of clusters (Dryver and Thompson, 2007). Each of these two methods was proposed to reduce the sampling cost though the use of the stopping rule results in biased estimates. Despite this bias, the new estimator resulted in higher efficiency gain in comparison to the without replacement of cluster design. It was also more efficient compared to the stratified design which is known to reduce final sample size when networks are truncated at stratum boundaries. The above evaluation was based on simulated and real data. The real data was the distribution and counts of hartebeest, elephants and oryx obtained in the same census as above. The bias attributed by the stopping rule has not been evaluated analytically. This may not be direct since the truncated network formed depends on the initial unit sampled (Gattone et al., 2016a). This and the order of the bias however, deserves further investigation as it may help in understanding the effect of the increase in the initial sample size together with the population characteristics on the efficiency of the proposed estimator. Chapter four modeled data that was obtained using the stratified strip ACS (as described in sub-section (3.1)). This was an extension of the model of Rapley and Welsh (2008) by modeling data that was obtained from a different design, the introduction of an auxiliary variable and the use of the without replacement of clusters mechanism. Ideally, model-based estimation does not depend on the design or rather how the sample was obtained. This is however, not the case if the design is informative; such as the ACS design. In this case, the procedure that was used to obtain the sample was incorporated in the model. Both model-based and design-based simulations were conducted using artificial and real data. The study and the auxiliary variable for the real data was the distribution and counts of elephants collected during an aerial census in parts of Kenya and Tanzania in October (dry season) and April (wet season) 2013 respectively. Areas of possible future research include predicting the population total of African elephants in all parks in Kenya. This can be achieved in an economical and reliable way by using the theory of SAE. Chapter five compared the different proposed strategies using the elephant data. Again the study variable was the elephant data from October (dry season) 2013 and the auxiliary variable was the elephant data from April (wet season) 2013. The results show that the choice of particular strategy to use depends on the characteristic of the population under study and the level and the direction of the correlation between the study and the auxiliary variable (if present). One general area of the ACS design that is still behind, is the implementation of the design in the field especially on animal populations. This is partly attributed by the challenges associated with the field implementation, some of which were discussed in section 2.3. Green et al. (2010) however, provides new insights in undertaking the ACS design during an aerial survey such as how the aircraft should turn while surveying neighboring units. A key point throughout the dissertation is the reduction of cost during a survey which can be seen by the reduction in the number of units in the final sample (through the use of stopping rule, use of stratification and truncating networks at stratum boundaries) and ensuring that units are observed only once (by using the without replacement of cluster sampling technique). The cost of surveying an edge unit(s) is assumed to be low in which case the efficiency of the ACS design relative to the non-adaptive design is achieved (Thompson and Collins, 2002). This is however not the case in aerial surveys as the aircraft flies at constant speed and height (Norton-Griffiths, 1978). Hence the cost of surveying an edge unit is the same as the cost of surveying a unit that meets the condition of interest. The without replacement of cluster technique plays a greater role of reducing the cost of sampling in such surveys. Other key points that motivated the sections in the dissertation include gains in efficiency (in all sections) and practicability of the designs in the specific setting. Even though the dissertation focused on animal populations, the methods can as well be implemented in any population that is rare and clustered such as in the study of forestry, plants, pollution, minerals and so on.
Nos recherches ont exploré l’espace transculturel dans la dramaturgie québécoise contemporaine. Notre travail a été principalement basé sur le concept de transgressivité de Bertrand Westphal [WESTPHAL : 2007] et la notion de transculturalité proposée par Wolfgang Welsch [WELSCH : 1999].
La réflexion menée par Welsch nous a inspiré dans l’établissement des trois grands axes de notre analyse, autour desquels se sont articulées les dimensions transculturelles superposées : l’axe syncrétique, l’axe intime et l’axe cosmopolite. Ces axes ont déterminé le choix de notre corpus, provenant de l’époque transculturelle du Québec entre 1975 et 1995. L’axe syncrétique s’est dessiné à partir de la présence de cultures modernes interconnectées, où les façons de vivre ne se limitent pas aux frontières culturelles nationales. Elles les « transgressent » et se retrouvent dans d’autres cultures. L’axe intime découle de ce que les individus – le(s) Moi(s) – sont des hybrides culturels, chaque individu se formant par des attachements multiples. Ils interagissent entre eux, créant ainsi une transculturalité interne. L’axe cosmopolite renferme une dimension qui représente de nombreuses façons de vivre et diverses vies culturelles qui s’interpénètrent mutuellement. Elles interagissent entre elles, mais aussi avec des espaces considérés comme étant hors du contexte transculturel.
Nous avons tenu à développer notre projet autour des prémisses théoriques de la géocritique. Cela nous a conduit à établir une grille d’analyse spécifique afin de découvrir le mode de fonctionnement de l’espace humain transculturel. L’analyse s’est basée uniquement sur le texte dramatique. Des dispositifs inspirés de la géocritique ont dévoilé quelques caractéristiques primordiales des dimensions transculturelles superposées de la diversité québécoise.
Monetary Policy During Times of Crisis - Frictions and Non-Linearities in the Transmission Mechanism
(2017)
For a long time it was believed that monetary policy would be able to maintain price stability and foster economic growth during all phases of the business cycle. The era of the Great Moderation, often also called the Volcker-Greenspan period, beginning in the mid 1980s was characterized by a decline in volatility of output growth and inflation among the industrialized countries. The term itself is first used by Stock and Watson (2003). Economist have long studied what triggered the decline in volatility and pointed out several main factors. An important research strand points out structural changes in the economy, such as a decline of volatility in the goods producing sector through better inventory controls and developments in the financial sector and government spending (McConnell2000, Blanchard2001, Stock2003, Kim2004, Davis2008). While many believed that monetary policy was only 'lucky' in terms of their reaction towards inflation and exogenous shocks (Stock2003, Primiceri2005, Sims2006, Gambetti2008), others reveal a more complex picture of the story. Rule based monetary policy (Taylor1993) that incorporates inflation targeting (Svensson1999) has been identified as a major source of inflation stabilization by increasing transparency (Clarida2000, Davis2008, Benati2009, Coibion2011). Apart from that, the mechanics of monetary policy transmission have changed. Giannone et al. (2008) compare the pre-Great Moderation era with the Great Modertation and find that the economies reaction towards monetary shocks has decreased. This finding is supported by Boivin et al. (2011). Similar to this, Herrera and Pesavento (2009) show that monetary policy during the Volcker-Greenspan period was very effective in dampening the effects of exogenous oil price shocks on the economy, while this cannot be found for the period thereafter. Yet, the subprime crisis unexpectedly hit worldwide economies and ended the era of Great Moderation. Financial deregulation and innovation has given banks opportunities for excessive risk taking, weakened financial stability (Crotty2009, Calomiris2009) and led to the build-up of credit-driven asset price bubbles (SchularickTaylor2012). The Federal Reserve (FED), that was thought to be the omnipotent conductor of price stability and economic growth during the Great Moderation, failed at preventing a harsh crisis. Even more, it did intensify the bubble with low interest rates following the Dotcom crisis of the early 2000s and misjudged the impact of its interventions (Taylor2009, Obstfeld2009). New results give a more detailed explanation on the question of latitude for monetary policy raised by Bernanke and suggest the existence of non-linearities in the transmission of monetary policy. Weise (1999), Garcia and Schaller (2002), Lo and Piger (2005), Mishkin (2009), Neuenkirch (2013) and Jannsen et al. (2015) find that monetary policy is more potent during times of financial distress and recessions. Its effectiveness during 'normal times' is much weaker or even insignificant. This prompts the question if these non-linearities limit central banks ability to lean against bubbles and financial imbalances (White2009, Walsh2009, Boivin2010, Mishkin2011).
Automata theory is the study of abstract machines. It is a theory in theoretical computer science and discrete mathematics (a subject of study in mathematics and computer science). The word automata (the plural of automaton) comes from a Greek word which means "self-acting". Automata theory is closely related to formal language theory [99, 101]. The theory of formal languages constitutes the backbone of the field of science now generally known as theoretical computer science. This thesis aims to introduce a few types of automata and studies then class of languages recognized by them. Chapter 1 is the road map with introduction and preliminaries. In Chapter 2 we consider few formal languages associated to graphs that has Eulerian trails. We place few languages in the Chomsky hierarchy that has some other properties together with the Eulerian property. In Chapter 3 we consider jumping finite automata, i. e., finite automata in which input head after reading and consuming a symbol, can jump to an arbitrary position of the remaining input. We characterize the class of languages described by jumping finite automata in terms of special shuffle expressions and survey other equivalent notions from the existing literature. We could also characterize some super classes of this language class. In Chapter 4 we introduce boustrophedon finite automata, i. e., finite automata working on rectangular shaped arrays (i. e., pictures) in a boustrophedon mode and we also introduce returning finite automata that reads the input, line after line, does not alters the direction like boustrophedon finite automata i. e., reads always from left to right, line after line. We provide close relationships with the well-established class of regular matrix (array) languages. We sketch possible applications to character recognition and kolam patterns. Chapter 5 deals with general boustrophedon finite automata, general returning finite automata that read with different scanning strategies. We show that all 32 different variants only describe two different classes of array languages. We also introduce Mealy machines working on pictures and show how these can be used in a modular design of picture processing devices. In Chapter 6 we compare three different types of regular grammars of array languages introduced in the literature, regular matrix grammars, (regular : regular) array grammars, isometric regular array grammars, and variants thereof, focusing on hierarchical questions. We also refine the presentation of (regular : regular) array grammars in order to clarify the interrelations. In Chapter 7 we provide further directions of research with respect to the study that we have done in each of the chapters.