Tesis sobre el tema "Roots"

The ability of plant roots to penetrate soils is affected by several stimuli from the surrounding medium such as mechanical stresses and chemical changes. Therefore, roots have developed multiple responses to the several outer stimuli. Since plant roots have to face very complex problems to grow deeply into the ground, they are remarkable examples of problem-solving behaviour and adaptation to the outer constraints. The adaptation strategies of a natural root are not yet completely known and understood with exhaustive explanations. For this reason, mathematical models and experimental techniques applied to biological phenomena can perform a key role in translating the Nature adaptive solutions into engineering applications. The aim of this thesis is to provide further insights in understanding biological phenomena for the development of new technologies inspired by the adaptive ability of plant roots. Accordingly, both theoretical and experimental explanations to the adaptive behaviour of plant roots are proposed. The mathematical modelling is based on a modified version of the extended West, Brown and Enquist universal law, considering the root growth as an inclusion problem. The proposed equation has as a particular case a growth equation exploiting an approach similar to Lockhart taking into account the soil impedance. The influence of mechanical stresses and nutrient availability on the root growth are studied. The solutions of the analytical models are compared with experimental data collected in real and artificial soils. In addition, the theories and hypotheses of the root ability to grow in the apical region through nanoindentation, wettability, and photoelasticity are investigated. The first technique provided insights for the possible role and function at both different tissues levels and distances from the tip in the root movement and penetration during the growth. The investigation of root tissue properties revealed that the penetration and adaptation strategies adopted by plant roots could be enhanced by a combination of soft and stiff tissues. The second technique aimed to highlight the wettability of the apical zone and root hairs for the acquisition of water and nutrients. Finally, photoelastic experiments provided a non-invasive and in situ observation of plant roots growth and, by exploiting the fringe multiplication, a set up for the study of plant roots growing in edible gelatine is proposed.

The ability of plant roots to penetrate soils is affected by several stimuli from the surrounding medium such as mechanical stresses and chemical changes. Therefore, roots have developed multiple responses to the several outer stimuli. Since plant roots have to face very complex problems to grow deeply into the ground, they are remarkable examples of problem-solving behaviour and adaptation to the outer constraints. The adaptation strategies of a natural root are not yet completely known and understood with exhaustive explanations. For this reason, mathematical models and experimental techniques applied to biological phenomena can perform a key role in translating the Nature adaptive solutions into engineering applications. The aim of this thesis is to provide further insights in understanding biological phenomena for the development of new technologies inspired by the adaptive ability of plant roots. Accordingly, both theoretical and experimental explanations to the adaptive behaviour of plant roots are proposed. The mathematical modelling is based on a modified version of the extended West, Brown and Enquist universal law, considering the root growth as an inclusion problem. The proposed equation has as a particular case a growth equation exploiting an approach similar to Lockhart taking into account the soil impedance. The influence of mechanical stresses and nutrient availability on the root growth are studied. The solutions of the analytical models are compared with experimental data collected in real and artificial soils. In addition, the theories and hypotheses of the root ability to grow in the apical region through nanoindentation, wettability, and photoelasticity are investigated. The first technique provided insights for the possible role and function at both different tissues levels and distances from the tip in the root movement and penetration during the growth. The investigation of root tissue properties revealed that the penetration and adaptation strategies adopted by plant roots could be enhanced by a combination of soft and stiff tissues. The second technique aimed to highlight the wettability of the apical zone and root hairs for the acquisition of water and nutrients. Finally, photoelastic experiments provided a non-invasive and in situ observation of plant roots growth and, by exploiting the fringe multiplication, a set up for the study of plant roots growing in edible gelatine is proposed.

The project Roots and Routes is an intergenerational narrative connecting three locations: London, Mandeville and Stockholm, focusing primarily on the histories of women and non-binary people. It looks at what affect it has on our sense of cultural identity to grow up in the diaspora, disconnected from the country of our parents or grandparents. Roots and Routes presents the search for a sense of belonging, whilst existing in the in-between. This report explores the different elements of the project, through text and image.

Thesis (B.S.)--California Polytechnic State University, 2010.
Project advisor: Jim Ahern. Title from PDF title page; viewed on Mar. 24, 2010. Includes bibliographical references. Also available on microfiche.

This dissertation is comprised of two separate topics within the domain of polarization optical engineering. The first topic is a Mueller matrix roots decomposition, and the second topic is polarization computer generated holography. The first four chapters of the dissertation are on the topic of the Mueller matrix roots decomposition. Recently, an order-independent Mueller matrix decomposition was proposed in an effort to organize the nine depolarization degrees of freedom. Chapter 1 discusses relevant Mueller matrix decomposition prior art and the motivation for this work. In chapter 2, the critical computational issues involved in applying this Mueller matrix roots decomposition are addressed, along with a review of the principal root and common methods for its calculation. The choice of the pth root is optimized at p = 10⁵, and computational techniques are proposed which allow singular Mueller matrices and Mueller matrices with a half-wave of retardance to be evaluated with the matrix roots decomposition. A matrix roots algorithm is provided which incorporates these computational results. In chapter 3, the Mueller matrix roots decomposition is reviewed and a set of Mueller matrix generators are discussed. The parameterization of depolarization into three families, each with three degrees of freedom is explained. Analysis of the matrix roots parameters in terms of degree of polarization maps demonstrates that depolarizers fall into two distinct classes: amplitude depolarization in one class, and phase and diagonal depolarization in another class. It is shown that each depolarization family and degree of freedom can be produced by averaging two non-depolarizing Mueller matrix generators. This is extended to provide further insight on two sample measurements, which are analyzed using the matrix roots decomposition. Chapter 4 discusses additional properties of the Mueller matrix roots generators and parameters, along with a pupil aberration application of the matrix roots decomposition. Appendix C, adapted from a conference proceedings paper, presents an application of the matrix roots depolarization parameters for estimating the orientation of a one-dimensionally textured object. The last two chapters are on the topic of polarization computer generated holography. In chapter 5, an interlaced polarization computer-generated hologram (PCGH) is designed to produce specific irradiance and polarization states in the image plane. The PCGH produces a tangentially polarized annular pattern with correlated speckle, which is achieved by a novel application of a diffuser optimization method. Alternating columns of orthogonal linear polarizations illuminate an interlaced PCGH, producing a ratio of polarization of 88% measured on a fabricated sample. In chapter 6, an etched calcite square-wave retarder is designed, fabricated, and demonstrated as an illuminator for an interlaced polarization computer generated hologram (PCGH). The calcite square-wave retarder enables alternating columns of orthogonal linear polarizations to illuminate the interlaced PCGH. Together, these components produce a speckled, tangentially polarized PCGH diffraction pattern with a measured ratio of polarization of 84% and a degree of linear polarization of 0.81. An experimental alignment tolerance analysis is also reported.

Thesis: M. Arch., Massachusetts Institute of Technology, Department of Architecture, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 78-79).
Over the past two decades, more than 200 million people in China moved from rural to urban areas. These migrants fled the countryside, which is regarded as an economic wasteland in perpetual stagnation that is locked by feudal traditions and peasant values, to the largest cities. They sought to be connected to a modern China, one that is marked by a booming economy and pronounced popular culture. These rural- to-urban migrants have formed the largest peacetime inland migration in history. Mobility is a socially produced motion that often bears ideologies. It is associated with a desire for progress, freedom, and opportunity. The massive inland migration in China demonstrates the tremendous social force that aims to overcome the outdated social strata. However, as migrants move, limitations on mobility emerge. The Hukou, the household registration system in China, is an institutional framework that has entrenched the social strata for ages. Records of births, marriages, and moves identify each person with a place. As soon as migrants move from their designated origins, immobility appears: welfare exclusion, job inequity, urban transit inaccessibility, to name just a few. This thesis proposes to study this condition of mobility, immobility and estrangement in the district of Minhang, Shanghai, where 1.5 million migrants currently live and work. Scooter, an emerging fast and cheap personal vehicle, is the protagonist in this story of migrants. Linking closely to migrants' life, scooters are not only their primary means of transportation but also their means of production. Its mobility empowers migrants to move beyond their territory, while its unique scale and flexibility links to rich spatial possibilities.
by Xinyi Ma.
M. Arch.

The author presents the first detailed review of the pharmacological therapy of parkinsonism from ancient times until the near present (1980). It is not clear whether parkinsonism as it is now defined – a progressive neurodegenerative disorder of the basal ganglia characterized by sharply reduced striatal dopamine levels, particularly in the striatum – has always affected a significant minority of aged persons, but suggestive evidence to this effect in the older literature is reviewed. The major discussion commences, however, with the administration of various plant alkaloids to parkinsonian patients in the second half of the 19th century. Antiparkinsonian therapy since this time may be divided into a number of phases: 1. The employment of alkaloids derived from solanaceous plants: initially hyoscyamine, then hyoscine/scopolamine and atropine. The discovery and characterization of these alkaloids, and the gradual recognition that other pharmacologically useful solanaceous alkaloids (such as duboisine) were identical with one or other of these three compounds, is discussed. 2. With the outbreak of encephalitis lethargica following the First World War, parkinsonian patient numbers increased dramatically, leading to a multiplicity of new directions, including the use of another solanaceous plant, stramonium, of extremely high atropine doses, and of harmala alkaloids. 3. The so-called “Bulgarian treatment” was popularized in western Europe in the mid-1930s. It was also a belladonna alkaloid-based therapy, but associated with greater efficacy and fewer side effects. This approach, whether as actual plant extracts or as defined combinations of belladonna alkaloids, remained internationally dominant until the end of the 1940s. 4. Synthetic antiparkinsonian agents were examined following the Second World War, with the aim of overcoming the deficiencies of belladonna alkaloid therapy. These agents fell into two major classes: synthetic anticholinergic (= antimuscarinic) agents, such as benzhexol, and antihistaminergic drugs, including diphenhydramine. These agents were regarded as more effective than plant-based remedies, but certainly not as cures for the disease. 5. A complete change in direction was heralded by the discovery in 1960 of the striatal dopamine deficit in parkinsonism. This led to the introduction of L-DOPA therapy for parkinsonism, the first approach directed against an identified physiological abnormality in the disorder. 6. Subsequent developments have thus far concentrated on refinement or supplementation of the L-DOPA effect. Recent attempts to develop neuroprotective or -restorative approaches are also briefly discussed. The thesis also discusses the mechanisms by which the various types of antiparkinsonian agent achieved their effects, and also the problems confronting workers at various periods in the design and assessment of novel agents. The impact of attitudes regarding the etiology and nature of parkinsonism, particularly with regard to symptomatology, is also considered. Finally, the history of antiparkinsonian therapy is discussed in context of the general development of both clinical neurology and fundamental anatomical, physiological and biochemical research. In particular, the deepening understanding of the neurochemical basis of central nervous system function is emphasized, for which reason the history of dopamine research is discussed in some detail. This history of antiparkinsonian therapy also illustrates the fact that the nature of experimental clinical pharmacology has markedly changed throughout this period: No longer the preserve of individual physicians, it is now based firmly on fundamental laboratory research, the clinical relevance of which is not always immediately apparent, and which is only later examined in (large scale) clinical trials. It is concluded that antiparkinsonian therapy was never irrational or without basis, but has always been necessarily rooted in current knowledge regarding neural and muscular function. The achievements of L-DOPA therapy, the first successful pharmacological treatment for a neurodegenerative disorder, derived from the fruitful union of the skills and contributions of different types by laboratory scientists, pharmacologists and clinicians
Der Autor stellt die erste detaillierte Zusammenfassung der Entwicklung der pharmakologischen Therapie des Parkinsonismus vom Altertum bis in die jüngere Vergangenheit (1980) dar. Es ist nicht klar, ob der Parkinsonismus, wie er jetzt definiert wird – eine progressive neurodegenerative Störung der Basalganglien, die durch die zum scharf verringerten Dopamininhalt des Corpus striatum führende Degeneration der nigrostriatalen Bahn gekennzeichnet wird – zu allen Zeiten eine bedeutende Minderheit älterer Personen heimgesucht hat, verlockende Hinweise darauf findet man aber in der älteren Literatur. Die Hauptdiskussion beginnt jedoch mit der Anwendung verschiedener Pflanzenalkaloide bei Parkinson-Patienten in der zweiten Hälfte des 19. Jahrhunderts. Die Geschichte der Parkinson-Therapie seit dieser Zeit läßt sich in eine Serie von Phasen gliedern: 1. Die Anwendung von aus den Solanazeen isolierten Alkaloiden: zuerst Hyoscyamin, später Hyoscin/Skopolamin und Atropin. Die Entdeckung und die Charakterisierung dieser Alkaloide und die allmähliche Feststellung, daß andere pharmakologisch nützliche Solanazeen-Alkaloide (z.B. Duboisin) mit einem oder anderem dieser schon bekannten Mittel identisch waren, werden diskutiert. 2. Mit dem Ausbruch der Encephalitis lethargica nach dem Ersten Weltkrieg stieg die Anzahl von Parkinson-Patienten dramatisch an, was zu einer Vielfältigkeit neuer therapeutischer Richtungen führte: Der Einsatz des auch zu den Solanazeen gehörenden Stramonium, die Verabreichung von extrem hohen Atropindosen, und die Benutzung von Harmala-Alkaloiden waren insbesondere hochgeschätzt. 3. Die sogenannte “Bulgarische Kur” verbreitete sich schnell in Westeuropa in der Mitte der dreißiger Jahre. Es handelte sich dabei ebenfalls um eine auf Tollkirsche-Alkaloiden basierte Therapie, der jedoch höhere Wirksamkeit und wenige Nebenwirkungen zugemutet wurde. Diese Methode, vermittels der Verabreichung tatsächlicher Tollkirschenextrakte bzw. definierter Kombinationen von Belladonna-Alkaloiden, beherrschte die Parkinson-Therapie bis zum Ende der vierziger Jahre. 4. Nach dem Zweiten Weltkrieg wurden synthetische Parkinson-Mittel überprüft, in der Hoffnung, die Mängel der bisherigen anticholinergen Therapien überwinden zu können. Diese Mittel teilten sich in zwei Hauptkategorien ein: synthetische anticholinerge (= antimuskarine; z.B. Benzhexol) und antihistaminerge Mittel (z.B., Diphenhydramin). Diese Arzneimittel wurden als wirkungsvoller als pflanzliche Therapien angesehen, jedoch sicherlich nicht als Heilmittel für die Krankheit. 4. Eine gründliche Richtungsänderung der Parkinson-Therapie kündigte sich mit der Entdeckung (1960) des striatalen Dopamindefizits im Parkinsonismus an. Diese führte zur Einführung der L-DOPA-Therapie, der ersten Parkinson-Therapie, die gegen eine genau definierte physiologische Abnormität gerichtet war. 5. Die darauf folgenden Entwicklungen haben sich bis heute auf Verfeinerung bzw. Ergänzung des L-DOPA-Effektes konzentriert. Neuere Ansätze, neuroprotektive bzw. -restorative Therapien zu entwickeln, werden kurz behandelt. Die Arbeit diskutiert auch die Mechanismen, die der Wirksamkeit der verschiedenen Parkinson-Mittelarten zugrunde liegen, und auch die Probleme, die Forscher bei der Entwicklung und Bewertung neuartiger Mittel konfrontiert haben. Diese Diskussion zieht auch in Betracht die Auswirkung der Haltung des jeweiligen Forschers betreffend der Ätiologie und Natur des Parkinsonismus auf die Beurteilung neuer therapeutischer Möglichkeiten. Schließlich wird die Geschichte der Parkinson-Therapie im Kontext der allgemeinen Entwicklung der klinischen Neurologie als auch der grundlegenden anatomischen, physiologischen und biochemischen Forschung während dieser Periode behandelt. Insbesondere wird das wachsende Verständnis der neurochemischen Grundlagen der Funktion des Zentralnervensystems hervorgehoben, indem die Geschichte der Dopaminforschung ausführlich behandelt wird. Die Geschichte der Parkinson-Therapie weist auch darauf hin, daß sich die Natur der experimentellen Pharmakologie während dieser Periode grundsätzlich geändert hat. Sie liegt nämlich nicht mehr im Zuständigkeitsbereich des einzelnen Arztes, sondern wird im Gegenteil auf grundlegender Laborforschung aufgebaut, deren klinische Bedeutung nicht immer sofort deutlich ist. Erst später werden die Ergebnisse dieser Grundlagenforschung in großangelegten klinischen Versuchen bei Patienten überprüft. Es wird gefolgert, daß die Parkinson-Therapie zu keiner Zeit als ohne vernünftige Grundlage bzw. irrational betrachtet werden darf. Sie ist jedoch immer dem aktuellen Wissensstand betreffend neuraler und muskulöser Funktion entsprechend geregelt worden. Der Erfolg der L-DOPA-Therapie, der ersten langfristig wirksamen pharmakologischen Behandlung einer neurodegenerativen Krankheit, ist das Ergebnis der ertragreichen Vereinigung der Fähigkeiten und verschiedenartigen Beiträge von Grundlagenforschern, Pharmakologen und Klinikern

Abstract ROOTS – What Could Emerge Out of Thinking and Acting Networked ROOTS as Design?   This bachelor’s thesis uses ROOTS as a method designed to engage in both thinking and acting inside networks, by creating a hydroponic gardening network. As a designer one engages in many different fields of design. The most complicated design is designing networks with function, interlaced and embedded in everyday life. This is known as accountability, to be accountable to ones decisions and to act on many perspectives when designing. Accountability is designing from somewhere, and being aware of where that somewhere stems from. ROOTS visualizes accountability in a network, as accountability entails thinking and acting inside a network, and by doing so one actively engages in thinking about futures and design as a whole. When asking oneself what could emerge out of thinking and acting networked ROOTS as design, one begins to speculate in matters of vast networked complexity. From observation using methods such as ANT, the technologic extension T-ANT and also conducting a study in messiness, information is created and from the information, valuing becomes present, from valuing knowledge grows, from knowledge comes accountability and the network creates another cycle of ROOTS.   Keywords: Design, Network, Accountability, Complexity

This study examines the foundation of contemporary Cree performance, tracing its existence to traditional Cree narratives. Contained within traditional Cree stories is the trickster, Wasakaychak. These oral stories are shared collectively, providing the community with relevant cultural knowledge. The thesis concludes that contemporary Cree playwrights and performers such as Shirley Cheechoo and Margo Kane maintain the roles of traditional storytellers because their work informs its audience about the history of the land and also comments on the state of the community. This study further demonstrates how the mythological character, Wasakaychak, remains an active part of Cree society by examining his significance within Tomson Highway's plays, The Rez Sisters and Dry Lips Oughta Move to kapuskasing.
v, 107 leaves ; 28 cm.

Militarism in pre-World War Two Japan was a product of Japan's culture, manifested within its distinctive internal domestic institutions, stimulated by the encroaching external pressures, and is distinct from militarism anywhere else in the world. The culture of Japan emphasized the group over the individual, a strong sense of hierarchy, and a profound pride in the divine nature of the national essence. The abrupt intrusion of the technologically advanced Western civilization triggered an "insider-outsider" mentality within Japan that rejected participation in the Western diplomatic, and economic cabals which denied Japan its true equal (or, to some, superior) position in the community of nations. Japan's pre-war militarism clearly can be defined as the mobilization of the entire society, drawing upon an essentially homogeneous outlook, to achieve a position within the international system which reflected the cultural perception of Japan's "chosen" status (derived from centuries of Shinto influence) within the family of man. The martial segments within Japanese society used the "alien" international system, largely defined at the time in Imperial colonial military terms, to buttress the martial segments within Japanese society and to justify the expansion of their influence.

Thesis advisor: Daniel J. McKaughan
When you learn that you disagree with an epistemic peer, what should you believe about the proposition you disagree about? The epistemology of peer disagreement has made considerable progress in answering this question. But to this point, we have largely neglected a significant resource which can help us to determine how peers who disagree can rationally respond to their disagreement. Closely examining actual disagreements in scientific and nonscientific contexts can help us to understand why peers find themselves in disagreement. And knowing why you disagree with your peer can help you to understand how you can rationally respond to your disagreement. Examining specific scientific and nonscientific disagreements shows us that some peers disagree because they disagree about what evidence is relevant to the proposition they disagree about. Dual disagreements about propositions and evidence can be found in numerous areas of disagreement, including ethical, political, philosophical, and scientific arenas. When you find yourself in these dual disagreements, you can rationally believe that your belief is rational and that your peer’s belief, though it diverges from yours, is also rational. But some philosophers have suggested that this situation in which you and your peer have rational beliefs and recognize each other as holding rational beliefs is impossible. A primary motivation for thinking that at least one of you must be believing irrationally is the thesis of Uniqueness about rationality, which states that at most one doxastic attitude can be rationally held given a body of evidence. However, when you consider the epistemic context of your actual disagreements with your peer carefully, you need not think that at least one of you is believing irrationally, even if Uniqueness is true. In response to your disagreement with a peer who disagrees with you both about what evidence is relevant to the proposition you disagree about and the proposition itself, you can even rationally hold a belief which splits the connection between your evidence and your evidence about your evidence. When we consider their epistemic contexts in full relief, peers in disagreement can simultaneously be believing rationally, even if only one of them is right
Thesis (PhD) — Boston College, 2019
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Philosophy

Many concerns contributed to the creative success of Charles Darwin’s theorizing, including his humble character, reading Wordsworth, courting Emma for his wife, and considering the origins of creative thought in a material mind. Creativity is not straightforward; in Darwin’s case, it was fed by diverse interests, literary sensitivities, character traits, unusual introspection and even thoughts of marriage.

During the time frame of this study, the two important years between his return from the Beagle and his Malthusian insight that led to natural selection, Darwin twice read The Excursion and fell in love. While he thought hopefully of Emma, he was focused on reproduction to understand species transmutation and pondered evolved roots for emotions like love, thus linking his sexual and creative stimulation. Part of his drive to succeed was for Emma’s approval, to be a victorious naturalist and demonstrate that he would be a good provider. Emma appreciated Darwin’s humble character, a trait that also allowed him to question belief systems and intellectual conceits that restricted other naturalists. Darwin noted that many of his peers were blocked from understanding species transmutation by their intellectual vanities—like the idea that man was the crown of creation instead of just one species in nature’s panoply.

In the intellectual culture of Darwin’s time creationism was science, while scientists competed with poets for authority over explaining nature. Wordsworth epitomized creativity while asserting that The Excursion’s themes were man, nature and human life—parallel to Darwin’s. Wordsworth’s insights into human emotions, morality and creativity were important to Darwin, who needed to explain all human traits, physical, emotional and mental, as evolved from simpler animals. Darwin reflected on the roots of imaginative thought and proposed a process for thinking that he applied it to his own theorizing; from nascent generation of ideas through rigorous dialectic testing to solid conclusions, thus demonstrating thoughts in competition.

The strong correlation between the productivity of Darwin’s theorizing and his humility, poetry, Emma and considerations of creativity, offers new insights into the path of his theorizing, and perhaps into the origins of creativity itself.

Various generalizations of the Artin's Conjecture for primitive roots are considered. It is proven that for at least half of the primes p, the first log p primes generate a primitive root. A uniform version of the Chebotarev Density Theorem for the field ${ cal Q}( zeta sb{l},2 sp{1/l})$ valid for the range $l < { rm log} x$ is proven. A uniform asymptotic formula for the number of primes up to x for which there exists a primitive root less than s is established. Lower bounds for the exponent of the class group of imaginary quadratic fields valid for density one sets of discriminants are determined.

During the last twenty-five years of research and real-world studies accomplished all over the globe, space syntax has consistently shown that movement patterns in cities and buildings tend to be strongly related to configurational properties of their respective spatial layouts. It has also been shown that individuals’ trajectories in virtual worlds are affected by the syntactic properties of these environments, and that the resulting emergent patterns may explain the detected correlations between configurational properties of space and movement patterns in real-world scenarios. However, none of these studies have so far attempted to elicit why these regularities occur at a more fundamental, cognitive level. In other words, they have not yet answered how the idea of spatial configuration shapes a person’s qualitative assessments and subsequent usage of spatial networks. This is the topic of this thesis. What kind of information do people extract from spatial configurations? How is this information used when assessing a spatial network qualitatively? How is this information used when one has to use such a network? These are some of the questions that this thesis will attempt to answer. This thesis will focus on map usage. By analysing how people interact with maps, this thesis will attempt to shed light on the processes by which people internalise configurational information and are able to define qualitative judgements that may be use in real-world scenarios. As a result, this thesis aims to be a further step in the ongoing process of linking space syntax with cognitive theory and therefore to contribute in the search of the cognitive roots of space syntax.

Reinforcement of soil by fibrous roots is crucial for preventing soil erosion and degradation,yet the underlying mechanisms are poorly understood. Without fully understanding root enmeshment within the soil matrix, and root biomechanical properties key for increasing soil shear strength, adoption in main stream civil engineering, understanding of natural systems and implications to agricultural soil management will be limited. Within this thesis theunderlying processes that drive root reinforcement of soils were assessed through a variety oflaboratory and field based experiments. This included recent advances in geotechnical engineering and model plant lines with specific root traits. Plant lines were barley (Hordeum vulgare) from a mapping population where differences in root hairs, tortuosity and lignin biosynthesis were previously identified by screening large numbers of mutants.The initial hypothesis was that root numbers and area would control shear reinforcement, this was tested by altering planting density in both glasshouse and field experiments using one barley variety. After 5 weeks in the field, planting density was related to both reinforcement and root area ratio (RAR), with a 6.7 ?1.40 kPa, or 190%, increase in shear strength between 0 and 950/m2. By 20 weeks in the field shear strength increased by only 29%. The glasshouse study showed an increase of 53%, with a positive correlation to planting density.Relationships between root number and shear strength were not explicit, however, highlighting further possible interactions between soil shear strength and root inclusions. Various underlying processes were then investigated. Barley mutants, with differences in root hairs and tortuosity, were compared to parent lines. Hairless mutants had different root tensile strength characteristics, but experimental difficulties (malfunctioning logging hardware) prohibited detection of impacts on shear strength. A refined study was then performed that also incorporated the influence of abiotic stress from compaction and waterlogging. Barley with down-regulated lignin biosynthesis (Bowman 140) had increased nodalroot tensile strength of 37% compared to the parent line (Bowman Line) under good growth conditions, but this changed to -31% for compacted and 26% for water-logged soil. In addition to abiotic stress, the age of the roots (measured as distance from root tip) type of root (seminal, nodal or lateral) had a large impact on biomechanical behaviour.

Mestrado em Economia Internacional e Estudos Europeus
A Dinamarca é uma pequena economia aberta que, durante os anos 1980 e 1990, conseguiu resolver desequilíbrios macroeconómicos e foi reorientada para a exportação. Mais recentemente, e apesar de ter sido seriamente afectada pela crise internacional, a Dinamarca conseguiu manter o seu deficit e taxas de desemprego abaixo da média da UE25. Que razões explicam o desempenho da economia dinamarquesa nos últimos anos? Para se encontrar uma resposta recorreu-se às seguintes questões de pesquisa: - Como é que a economia dinamarquesa se comportou de 1950 até 2010/11? O ponto de partida serão os anos 1950. A análise abrangerá a década de 1970, onde vários desequilíbrios económicos foram construídos, passando pelos anos 1980 e 1990, onde reformas económicas reorientaram o país em direcção à sustentabilidade fiscal, exportações e crescimento económico. A análise acabará na década de 2000 onde, após um período de crescimento consistente, a Dinamarca é atingida pelas mais recentes crises económicas internacionais, e quando, mais tarde, em 2011, estabelece as suas metas e estratégias para atingir a sustentabilidade fiscal nos próximos anos. Que outros factores específicos, além de políticas governamentais e acontecimentos históricos, explicam o desempenho económico da Dinamarca? Depois de delineada a evolução macroeconómica, procuraram-se os elementos estruturais que contribuem para a explicação desse desempenho. Cinco características específicas, e em que medida estas moldaram o desempenho económico da Dinamarca e a ajudaram a enfrentar a globalização e constantes mudanças económicas, serão consideradas. As cinco características mostraram influenciar positivamente o desempenho global da Dinamarca.
Denmark is a small and open economy which, during the 1980s and 1990s, succeeded in resolving macroeconomic imbalances and in reorienting the economy to exports. Nowadays, despite having been seriously affected by the most recent global crises, Denmark has managed to keep its deficit and unemployment rates below the EU25 average. What reasons explain the Danish economy's performance in the latest years? In order to understand it two research questions will be considered: - How did the Danish economy perform from the 1950s until 2010/11? The 1950s will be the starting point. The analysis will go through the 1970s, where several economic imbalances were built up, passing by the 1980/90s where economic reforms reoriented the country towards fiscal sustainability, exports and economic growth. The outline will end in the 2000s where, after a period of consistent growth, Denmark is hit by the international economic crises, and later, in 2011, establishes its targets and strategies for the fiscal sustainability to be ensured in the coming years. What other specific factors, apart from governmental policies and historical happenings, explain Denmark´s economic performance? Five selected features of the Danish economy, and the extent in which they have shaped Denmark´s economic performance and have helped Denmark facing globalization and changing environments, will be considered. All the five features have demonstrated to provide the Danish economy with positive inputs contributing to Denmark´s overall performance.

In searching for restorative stories that elevate understanding and engender the capacity for seeing through the cultural chaos and confusion of modern times, this dissertation turns to Egypt at the beginning of its recorded history, approximately 3100 BCE. The ancient Egyptians faced many of the same challenges facing the world today, and they learned to weather them by creating a resilient cultural model that endured cycles of growth and decline. Their culture perpetuated while adapting and transforming. In their surviving records are some of their rituals, practices, and beliefs that provide much-needed perspectives, observations, and stories that contributed to their own renewal and capacity to regenerate their culture.

The mythological roots of renewal in ancient Egypt reveals one deity in particular who embodies the capacity to harmonize and balance the opposites—Ma‘at. She is central to the act of fostering daily reciprocal relationship and maintaining the flow of energy between the divine and the human realms. She is both the daughter of the solar god Re and his source of life. She is the embodiment of the cosmic patterns and natural laws. She is the incarnation of the offerings to the gods and their reciprocal response flowing back to the human realm. She governs the tides of justice, truth, balance, and harmony.

The collective psyche’s inherent capacity for renewal and resilience is revealed through Ma‘at’s story and prominence in Egyptian history. Their images and literature reveal that in the presence of Ma‘at, it is possible for human consciousness to discover the transcendent space where opposites reconcile to initiate new harmony, create unity, and guide all things to their rightful place. Balancing and harmonizing any duality creates a continuous circulation of energy in the psyche. This circulation has the potential to birth a conscious, ethical heart, an awakened heart which—as these ancient people would say—directs our saying and our doing. By recognizing Ma‘at’s essential characteristics, understanding her relationship with her fellow deities, and identifying her foundational role within the ancient Egyptian civilization it is possible to participate in the awakening of Ma‘at’s roots of renewal in our own times.

This thesis argues that the modern notion of free-speech was born within the Westphalian nation-state. It suggests that the legal rights framework - particular to the Westphalian nationstate - not only legitimizes and legalizes the right to free-speech, but also enables us to invoke legally the necessary limitations that demand the limitation of free-speech in certain contexts. However, such a legal-rights framework is exclusive to the nation-state and cannot be enforced on an international level, outside of the nation-state boundary. With reference to examples on an international level, this thesis demonstrates that calls for the limitation of free-speech are indeed legitimate and necessary but cannot be enforced on an international level for the reasons just mentioned. In order to address this problem, this thesis proposes a framework - based on a Kantian model - that enables us to invoke the limitation of free-speech on an international level without appealing to a legal-rights discourse to do so.

The effect of removing soil water stress on fine root growth and the pattern of water use was studied by irrigating a small plot (20 m x 20 m) of 40 year old Sitka spruce. A control plot was established close by. Soil water content and soil matric potential were measured independently on both plots at several depths. Root growth was measured using monthly coring for the surface horizons (c. 10 cm depth) and ingrowth cores to study rooting at depth. In the absence of irrigation the 2 plots had similar water regimes. The irrigation kept matric potential > 20 kPa and water content > 20%. Areas between trees were wetter than areas close to stems and wetted up more during periods of rainfall. This is in contrast to young plantations where stemflow accounts for a much larger proportion of precipitation reaching the forest floor. At field capacity most of the water uptake was from near the surface but as the profile dries the proportion from depth increases, at the end of a dry period 50% of uptake was from the bottom half of the rooted zone. Water uptake from below the rooted zone was small. Irrigation had a significant effect on root tip density and on small root mass but not on fine and dead root masses. Root tip density stayed high through the summer with irrigation but fell on the control plot, the number of tips began to increase earlier on the control plot. This is interpreted as irrigation increasing the longevity of tips from 2-3 months (control) to 5 months. Rewetting of the soil in autumn appears to act as a cue for an increase in root growth. Irrigation had no effect on root growth at depth and there was no difference in growth at different depths on either plot.

The length of the primary root and the density of lateral roots determine the architecture of the root. In this thesis the effect of NAA, ABA and the NO donor SNP alone as well as the combination of ABA or NAA with SNP on lateral root development was investigated. The interaction between CPTIO, a NO scavenger, and NAA or SNP is also reported. Following preliminary experiments in which it was observed that the aerial part of the seedling influenced LR growth and that there was a possible inhibitory effect of light on cultured root tips, experiments were conducted with excised roots tips in the dark. NAA was shown to have the potential to initiate LRs across a wide concentration gradient with the total number of LRs and initiated lateral root primordia (LRP) remaining constant across the range of concentrations tested. Over the last decade, nitric oxide (NO), a bioactive molecule, has been reported to be involved in the regulation of many biological pathways. The presence of NO in the system provided via sodium nitroprusside (SNP), promoted LRP initiation based on the NAA concentration gradient; but without changing the total LR initiation, that is LRs plus primordia density remained constant along the concentration gradient of NAA. The absence of LR and LRP in the treatments of CPTIO (a NO scavenger) with SNP or NAA suggests that NO regulates LRP initiation triggered by NAA, which is in agreement with the recent paper published after the commencement of this study (Correa-Aragunde et al., 2006). In agreement with previous studies, ABA inhibited lateral root development by reducing LR density and the number of LRs. The experiments with fluridone, an ABA biosynthesis inhibitor, may indicate that endogenous ABA was at sufficient concentrations in the excised root tips to inhibit primordia initiation. In this study, evidence is presented for the first time to show that SNP can relieve the inhibitory effect of ABA on LR density and number of LRs suggesting the NO, released from SNP, acts downstream of ABA. Overall these data confirm a critical role for NO in LR initiation.

In the United States, illnesses associated with fresh produce are increasing in frequency.  While contamination risks are present at every aspect of the farm to fork continuum, post-harvest practices holds the potential for cross-contamination of large amounts of product.  Post-harvest contamination risks for hydroponically grown lettuce packaged with intact roots and sold as "living lettuce"" are poorly understood.  In this study, transmission of Salmonella enterica serotype Enteritidis to the roots and leaves of butterhead lettuce was studied when contamination was introduced during typical handling practices.  The effectiveness of random sampling strategies for selection of Salmonella contaminated leaves was assessed by co-inoculating the Salmonella solution with Glo Germ™ and comparing recovery from blacklight selected leaves.  The recovery of Salmonella was improved by only 0.5 log CFU/g when blacklight was used to select Glo Germ™ contaminated leaves (P=0.05). This suggests random leaf selection as described by current FDA protocols is adequate. In addition, this study showed rapid transfer of Salmonella from liquid to the roots and sub-sequentially to the leaves of living lettuce.  Salmonella persisted but did not grow on leaves when stored at 4˚C for 18-days. Storage at 12˚C was associated with 2 log CFU/g increases in Salmonella on roots after 18-days storage (P=0.0002), while 4˚C storage was associated with a decrease of 0.4 log CFU/g Salmonella on roots (P=0.0001). Growth occurred only under temperature abuse conditions.  This reinforces the need for maintaining temperature control and highlights the importance of identifying risks associated with post-harvest handling during hydroponic production and distribution.
Master of Science in Life Sciences

Higher plants respond to biotic and abiotic stress through activation of the JA pathway, which suppresses growth and activates defence. This project describes the expression and subcellualr localisation of two of the JA signalling proteins, and the mechanism of MeJA-mediated root growth inhibition. By using immunolocalisation and reporter gene expression, localisation of COIl was shown at the subcellular and tissue level. Although COIl was constitutively expressed in the root and shoot, increased expression of COIl in MeJA-treated roots suggested that the COIl gene and the COIl protein was also regulated by the JA pathway. Co-localisation of COIl and JAZ3 protein in the nucleus confirmed that the previously reported interaction between COIl and JAZ3 took place in the nucleus. To investigate the morphological basis of root growth inhibition by MeJA, time-lapse and still imaging by confocal microscopy was used to compare root growth parameters in untreated and MeJA-treated roots. MeJA inhibited root growth by reducing the number of dividing cells and rapidly-elongating cells, and causing earlier maturation of the elongating cells, so that they ceased elongating before reaching normal mature cell length. However, the rate of individual cell elongation was unaltered. The physiological basis of MeJA-mediated growth inhibition was investigated by examining the orientation of microtubules, acid efflux from the root elongation zone, and the effect of low water potential on root elongation. MeJA-treated roots had reduced acid efflux and water uptake in the elongating cells, while microtubule orientation was not required for the inhibitory effect. The crosstalk between JA, auxin, GA and ABA was studied by measuring the change of morphological growth parameters in mutants under different hormone treatment. The impaired MeJA-mediated growth inhibition in auxl indicated that MeJA reduced root growth by altering auxin transportation. However, MeJA-mediated growth inhibition was DELLA- and ABA- independent. In summary, MeJA reduced cell division by decreasing mitosis, and inhibited cell elongation by reducing acid efflux, which prevented water uptake, possibly by regulating the auxin transportation, in the Arabidopsis root.

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Plant roots have a dynamic relationship with the surrounding soil, which forms a vital interface for the terrestrial biosphere. Without a strong interface with soil, plants could not extract the necessary resources needed for growth. As a part of a multifaceted strategy, plant roots release a variety of high and low molecular weight compounds into the soil. This exudate is believed to increase water and nutrient uptake, form the first barrier of defence, and aid in the symbiosis with fungi and bacteria. This investigation reports on the identity and biochemistry of the polysaccharides released from the roots of several crops and one basal land plant, and explores their possible functions. Crops were grown hydroponically in order to isolate the polysaccharides released by their roots. After growth, the hydroponic media were screened with a library of monoclonal antibodies (MAb). The MAbs revealed the presence of arabinogalactan-protein (AGP), extensin, xylan and xyloglucan. Signatures of these polysaccharides were also determined by monosaccharide linkage analysis. By using anion-exchange Epitope Detection Chromatography, polysaccharides released into the hydroponic medium of the crops were separated for further immunochemical analysis. This analysis demonstrated that the polysaccharides released by wheat were part of a multi-polysaccharide complex, Root Exudate Complex 1 (REC1). A similar polysaccharide complex, formed of AGP-xyloglucan (REC2) was also found to be released by liverworts, which were not previously known to secrete polysaccharides. Novel soil analytics were developed in this study to decipher the effects of polysaccharides released by roots on soil aggregate status. Tamarind seed xyloglucan, xylan from birchwood, and isolated REC1 from wheat were each demonstrated to increase the abundance of soil aggregates, with REC1 shown to be most effective. This increase in the abundance aggregates may help plants to bioengineer the rhizosphere resulting in increased uptake of resources required for growth.