[ES] En respuesta a estreses de tipo biótico y abiótico, las plantas sintetizan proteínas de defensa y compuestos químicos de diversa naturaleza. Estos compuestos pueden actuar de manera directa, a través de propiedades antioxidantes, antifúngicas o antibacterianas, o actuar como metabolitos defensivos indirectos. Dentro de este último grupo de compuestos defensivos, cabe destacar a los compuestos fenólicos y los compuestos orgánicos volátiles (VOCs). En nuestro grupo de investigación se ha profundizado en el estudio de estos metabolitos secundarios implicados en la respuesta defensiva de las plantas. Por una parte, se identificó el ácido gentísico (GA) como una molécula señal que actúa de manera complementaria al ácido salicílico (SA) en infecciones de tipo sistémico. Además, se ha tratado de profundizar en el estudio de la biosíntesis del GA a través de la enzima salicilato 5-hidroxilasa (S5H), encargada de la conversión de SA a GA. Para ello, se ha llevado a cabo la caracterización fenotípica, molecular y química de plantas transgénicas de tomate que tienen silenciado el gen S5H mediante la técnica de RNA de interferencia (RNAi_S5H) frente a infecciones de tipo bacteriano y viroidal. Las plantas de tomate RNAi_S5H presentaron un aumento de resistencia frente a Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) y el viroide de la exocortis de los cítricos (CEVd). Del mismo modo, se llevaron a cabo análisis metabolómicos de estas plantas transgénicas RNAi_S5H tras ambas infecciones, observándose diferencias relacionadas con el metabolismo del SA, que parecen indicar que la homeostasis del SA es específica para cada interacción tomate-patógeno. Por otra parte, se identificaron algunos ésteres de (Z)-3-hexenol que eran emitidos de manera diferencial tras la infección bacteriana con la cepa avirulenta de Pst DC3000 en plantas de tomate cv. Rio Grande. Concretamente, tratamientos exógenos con el compuesto volátil butanoato de (Z)-3-hexenilo (HB) fueron capaces de inducir de manera significativa el cierre de estomas, la activación de genes defensivos y un aumento en la resistencia frente a la infección bacteriana. La eficacia de este compuesto como inductor de cierre estomático fue comprobada en diferentes cultivos agronómicos, como Arabidopsis, Medicago, Zea, Citrus y Nicotiana, confirmando su papel como un inductor de cierre estomático universal. Dado el potencial de este compuesto en agricultura, se emplearon aproximaciones genéticas, bioquímicas y farmacológicas para descifrar el mecanismo de señalización del cierre estomático mediado por HB. Una vez el volátil es percibido por los receptores de la planta, se activan diferentes componentes de la cascada de señalización defensiva, como canales permeables de Ca2+ o la producción de especies reactivas de oxígeno (ROS). Asimismo, el HB es capaz de desencadenar la activación de las proteínas quinasas activadas por mitógenos MPK3 y MPK6, induciendo el cierre estomático de una manera independiente a la síntesis y señalización mediada por ácido abscísico (ABA). Por último, la eficacia del HB fue evaluada en condiciones de campo frente a estreses tanto de tipo biótico como abiótico y en procesos de desarrollo como la maduración, proponiendo un uso del HB como un nuevo compuesto fitoprotector natural para el control de estreses de forma sostenible en agricultura. / [CA] En resposta a estressos de tipus biòtic i abiòtic, les plantes sintetitzen proteïnes de defensa i compostos químics de diversa naturalesa. Aquests compostos poden actuar de manera directa, a través de propietats antioxidants, antifúngiques o antibacterianes, o actuar com a metabòlits defensius indirectes. Dins d'aquest últim grup de compostos defensius, cal destacar als compostos fenòlics i els compostos orgànics volàtils (VOCs). En el nostre grup d'investigació s'ha aprofundit en l'estudi d'aquests metabòlits secundaris implicats en la resposta defensiva de les plantes. D'una banda, es va identificar l'àcid gentísic GA) com una molècula senyal que actua de manera complementària a l'àcid salicílic (SA) en infeccions de tipus sistèmic. A més, s'ha tractat d'aprofundir en l'estudi de la biosíntesi del GA a través d l'enzim salicilato 5-hidroxilasa (S5H), encarregada de la conversió de SA a GA. Per a això, s'ha dut a terme la caracterització fenotípica, molecular i química de plantes de transgèniques de tomaca que tenen silenciat el gen S5H mitjançant la tècnica d'RNA d'interferència (RNAi_S5H) enfront d'infeccions de tipus bacterià i viroidal. Les plantes de tomaca RNAi_S5H van presentar un augment de resistència enfront de Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) i el viroide de la exocortis dels cítrics (CEVd). De la mateixa manera, es van dur a terme anàlisi metabolómics d'aquestes plantes transgèniques RNAi_S5H després de totes dues infeccions, observant-se diferències relacionades amb el metabolisme del SA, que sembla indicar que l'homeòstasi del SA és específica per a cada interacció tomaca-patògena. D'altra banda, es van identificar alguns èsters de (Z)-3-hexenol que eren emesos de manera diferencial després de la infecció bacteriana amb el cep avirulent de Pst DC3000 en plantes de tomaca cv. Rio Gran. Concretament, tractaments exògens amb el compost volàtil butanoato de (Z)-3-hexenilo (HB) van ser capaces d'induir de manera significativa el tancament d'estomes, l'activació de gens defensius i un augment en la resistència enfront de la infecció bacteriana. L'eficàcia d'aquest compost com a inductor de tancament estomàtic va ser comprovada en diferents cultius agronòmics, com Arabidopsis, Medicago, Zea, Citrus i Nicotiana, confirmant el seu paper com un inductor de tancament estomàtic universal. Donat el potencial d'aquest compost en agricultura, es van emprar aproximacions genètiques, bioquímiques i farmacològiques per a desxifrar el mecanisme de senyalització del tancament estomàtic mediat per HB. Una vegada el volàtil és percebut pels receptors de la planta, s'activen diferents components de la cascada de senyalització defensiva, com a canals permeables de Ca2+ o la producció d'espècies reactives d'oxigen (ROS). Així mateix, el HB és capaç de desencadenar l'activació de les proteïnes cinases activades per mitógens MPK3 i MPK6, induint el tancament estomàtic d'una manera independent a la síntesi i senyalització mediada per l'àcid abscísic (ABA). Finalment, l'eficàcia del HB va ser avaluada en condicions de camp enfront d'estressos tant de tipus biòtic com abiòtic, i en processos de desenvolupament com la maduració, proposant un l'ús del HB com a nou compost fitoprotector natural per al control d'estressos de manera sostenible en agricultura. / [EN] In response to biotic and abiotic stress, plants synthesize defence proteins and chemical compounds from diverse nature. These compounds can act directly, trough antioxidant, antifungal or antibacterial properties, or indirectly as defensive metabolites. Among these group of defensive metabolites, phenolic compounds and volatile organic compounds (VOCs) present a major role. Our research group have a strong background in studying the role of plant secondary metabolites in plant defence mechanisms. On one hand, gentisic acid (GA) was first described as a signal molecule that acts complementary to salicylic acid (SA) in systemic infections. Furthermore, SA conversion to GA trough the salicylate 5-hydroxylase enzyme (S5H) has received much attention. For this purpose, S5H-silenced transgenic tomato plants (RNAi_S5H) have been phenotypically, molecularly, and chemically characterized against both, bacterial and viroidal inoculations. RNAi_S5H tomato plants resulted in enhanced resistance to both Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) and Citrus Exocortis Viroid (CEVd). Moreover, metabolomics analysis of these transgenic plants upon bacterial and viroid infections revealed differences related to SA metabolism, suggesting that SA homeostasis is specific for each tomato-pathogen interaction. On the other hand, some esters of (Z)-3-hexenol were identified to be differentially emitted by tomato cv. Rio Grande plants upon infection with the avirulent strain of the bacterium Pst DC3000. Particularly, treatments with the volatile (Z)-3-hexenyl butyrate (HB) resulted in significant stomatal closure, defence genes induction and enhanced resistance to the bacteria. Moreover, the efficacy of this compound as a stomata closer was tested in different agronomic crop as Arabidopsis, Medicago, Zea, Citrus y Nicotiana plants, postulating HB as a new universal stomata closer. Due to its potent properties, the signalling pathway of the HB-mediated stomata closure has been deciphered by using different genetic, biochemical, and pharmacological approaches. The perception of this volatile by plant receptors appeared to initiate different defence signalling events, including the activation of Ca2+ permeable channels or reactive oxygen species (ROS) burst. Moreover, HB triggered the activation of the mitogen-activated protein kinases MPK3 and MPK6, inducing stomatal closure independently of abscisic acid (ABA) biosynthesis and signalling. Additionally, HB efficacy has been also tested in field conditions and against both biotic and abiotic stresses, and also during ripening, proposing HB as a new natural phytoprotector for the sustainable control of stresses in agriculture. / This work was funded by Grant AICO/2017/048 from the Generalitat Valenciana and by Grant INNVAL10/18/005 from the Agència Valenciana de la Innovació (Spain). / Payá Montes, C. (2023). Secondary Metabolites in Plant Defence Mechanisms [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/193041

The aim of this study is to analyse and interpret L.Z. Sikwane's play: Matshediso from the perspective of didascalies. The study comprises five chapters. The aim, scope and methods of research are outlined and motivated in chapter one. In chapter two, an overview of the research into didascalies is undertaken. Questions such as: "what are didascalies?" "how do didascalies in a play help produce meaning and shape?" etc. are dealt with. Later, the study shows how didascalies are linked to the other structural elements of drama such as theme; plot; characters and setting. In chapter three an analysis and interpretation of Matshediso from the perspective of the importance of didascalies is undertaken. This analysis focuses on the plot; didascalies and characters; didascalies and space; and didascalies, props, and set. Limitations characterizing performance are also dealt with. In chapter four, an integrated interpretation of Matshediso is provided. Thereafter a set of guidelines for performing the play is developed. This covers aspects such as: stage setting; the characters; dialogue; sound and costume. Chapter five sum up the main findings of the study and the value of the didascalies approach. By way of conclusion, I argue that Sikwane has not just written a play, but also pictured how it should be performed. This is confirmed by the didascalies included in this play and the value of the didascalies approach. / M.A., African Languages, Potchefstroom University for Christian Higher Education, 2002

The main aim of the study is to compare the extent to which the need for autonomy, relatedness and competence of baby boomers, generation X, Y and Z employees of Denel Dynamics is being satisfied and how this influences motivational strategies. The issue of generation is becoming more important due to different ways and methods required to manage different generations. A quantitative study was done by means of a structured questionnaire which was used in to determine the motivational preferences of the participants. This questionnaire was developed by Van den Broeck, Vansteenkiste, De Witte, Soenens and Lens (2010) and is based on the self-determination theory developed by Deci and Ryan. Results indicate that baby boomers have a stronger need for autonomy as compared to the other generations. Similar needs for relatedness were shown by all the generations. In view of the findings, recommendations are made to management to optimize motivational strategies and these recommendations show how each generational needs relating to self-determination theory should be addressed. / MBA (Business Administration), North-West University, Potchefstroom Campus, 2015

The main aim of the study is to compare the extent to which the need for autonomy, relatedness and competence of baby boomers, generation X, Y and Z employees of Denel Dynamics is being satisfied and how this influences motivational strategies. The issue of generation is becoming more important due to different ways and methods required to manage different generations. A quantitative study was done by means of a structured questionnaire which was used in to determine the motivational preferences of the participants. This questionnaire was developed by Van den Broeck, Vansteenkiste, De Witte, Soenens and Lens (2010) and is based on the self-determination theory developed by Deci and Ryan. Results indicate that baby boomers have a stronger need for autonomy as compared to the other generations. Similar needs for relatedness were shown by all the generations. In view of the findings, recommendations are made to management to optimize motivational strategies and these recommendations show how each generational needs relating to self-determination theory should be addressed. / MBA (Business Administration), North-West University, Potchefstroom Campus, 2015

The aim of this study is to analyse and interpret L.Z. Sikwane's play: Matshediso from the perspective of didascalies. The study comprises five chapters. The aim, scope and methods of research are outlined and motivated in chapter one. In chapter two, an overview of the research into didascalies is undertaken. Questions such as: "what are didascalies?" "how do didascalies in a play help produce meaning and shape?" etc. are dealt with. Later, the study shows how didascalies are linked to the other structural elements of drama such as theme; plot; characters and setting. In chapter three an analysis and interpretation of Matshediso from the perspective of the importance of didascalies is undertaken. This analysis focuses on the plot; didascalies and characters; didascalies and space; and didascalies, props, and set. Limitations characterizing performance are also dealt with. In chapter four, an integrated interpretation of Matshediso is provided. Thereafter a set of guidelines for performing the play is developed. This covers aspects such as: stage setting; the characters; dialogue; sound and costume. Chapter five sum up the main findings of the study and the value of the didascalies approach. By way of conclusion, I argue that Sikwane has not just written a play, but also pictured how it should be performed. This is confirmed by the didascalies included in this play and the value of the didascalies approach. / M.A., African Languages, Potchefstroom University for Christian Higher Education, 2002

Despite the award of the Nobel Prize to Miguel Angel Asturias in 1967, he appears to have gone into decline with the rise of the nueva novela latinoamericana. Emir Rodrguez Monegal's influential but negative view in "Los dos Asturias" ignores several important points already raised by G.Yepes-Boscan's "Asturias, un pretexto del mito". Asturias' two major innovations are a functional incorporation of Latin American myth allied to audacious experimentation with language, and these are the acknowledged central features of the "new" novel. El Senor Presidente and Hombres de maz together prefigure all the varied manifestations of the nueva novela, an example of which is Asturias' own Mulata de tal.

Transmission electron microscopy (TEM) is a powerful tool for studying solidstate crystalline systems. With the advances in aberration correction, monochromation, and in situ capabilities, these microscopes are now more useful for addressing fundamental materials chemistry problems than ever before. This dissertation will illustrate the ways in which I have been using high-resolution imaging and in situ heating in the TEM during my Ph.D. research to investigate unique solid state chemistry questions. This dissertation will focus on four unique crystal systems: thermoelectric skutterudite crystals, vapor-liquid-solid (VLS) grown nanowires, and hafnium dioxide nanorods. Although these systems are very different from one another, high resolution and/or in situ heating in TEM is an integral part of each study. Through these techniques, we gain insight and knowledge of these systems that may have gone unknown through different analysis techniques. The experiments I will describe in some cases provide surprising and unexpected results that arise from the nanoscale nature of the materials and would be difficult to observe through bulk analytical methods. The work presented here helps to demonstrate the strength and versatility of TEM to address solid state chemistry questions.

On April 7, 2009, IBM celebrated the mainframe’s 45th year. Drawing on its roots in punch-card tabulators, the machine has come a long way to become many customers’ preferred e-business solution. Throughout its lifetime, IBM’s strategy adapted the machine to the changing market. During the late 1960s, the introduction of the System/360 provided customers with compatibility and scalability across various computer lines. Popularity of the system began to suffer during the client/server era of the 1990s but it quickly recovered as the z Series server line was developed to support e-business solutions. IBM’s strategy made the mainframe successful but continued improvements are still necessary to ensure its future success. / text

The series of compounds [M(H2O)2(15-crown-5)](NO3)2, M = Mg, Mn, Co, Cu and Zn, has been extended to include two new phases for M = Fe and two new phases for M = Ni. The system [M(H2O)2(15-crown-5)](NO3)2 is remarkable for having many high-Z’ phases (Z’ > 1) with similar packing and for having solid-solid phase transitions through which there is no significant loss of crystallinity. The synthesis of the analogous Ni complex was carried out. Single-crystal X-ray diffraction showed that the coordination of the Ni2+ ion is different from that of the other six M2+ ions in the system [M(H2O)2(15-crown- 5)](NO3)2. High temperature phases with high Z’ (8) were isolated for M = Mg, Fe and Zn. The refinements of such phases are challenging because of the lack of information in the diffraction patterns. Full details of the refinements for these three phases are discussed. Six other Ni(II) complexes consisting of Ni2+, NO3-, 15-crown-5 and different solvents were found when efforts were made to synthesize the compound [Ni(H2O)2(15-crown- 5)](NO3)2. In these chemically different environments, the Ni2+ ions are not coordinated by the 15-crown-5 molecules; rather, one-dimensional H-bonded chains are formed from uncomplexed 15-crown-5 molecules and the Ni(II) complexes. Among these six Ni(II) complexes, the compounds [Ni(H2O)6](NO3)2·(15-crown-5)·H2O, [Ni(H2O)6](NO3)2·(15-crown-5)·2H2O and [Ni(H2O)2(MeCN)(NO3)2]·(15-crown- 5)·MeCN were found to have reversible solid-solid phase transitions between structurally related phases. In all of these transitions, no significant crystal damage was detectable. The two latter systems are unusual because their phase sequences include three transitions and four phases between 90 and 295 K and because of the existence of high-Z’ phases. These high-Z’ phases are best depicted as being intermediate to low- and hightemperature phases. A method based on thermal analyses and X-ray diffraction has been developed for studying such sets of phase transitions.

Ce document résume et ordonne quelques dix années de recherche de son auteur dans le domaine des mesures de précision électrofaibles. Le lecteur y trouvera la description de mesures d'observables de quarks lourds produits au pôle du boson Z et étudiés par le détecteur ALEPH auprès du collisionneur électron-positron LEP jusqu'à des analyses phénoménologiques des données de physique des saveurs conduites au sein du groupe CKMfitter. Une large partie de ce document est consacrée aux travaux non encore publiés de conception, de tests, de production, d'installation et de mise en œuvre des dispositifs électroniques qui équipent le détecteur de pied de gerbes du calorimètre électromagnétique de l'expérience LHCb auprès du LHC.