Une nouvelle méthode, simple et rapide, a été développée pour isoler dans le miel différents antimicrobiens usuellement recherchés en contrôle sanitaire et appartenant à quatre classes différentes: les sulfamides, les tétracyclines, les macrolides et lincosamides associés et les aminoglycosides. Ces molécules antimicrobiennes sont analysées par chromatographie liquide couplée à la spectrométrie de masse en tandem (CL-SM/SM) après avoir été extraites de l’échantillon de miel par une méthode d’extraction unique. Afin de définir les conditions optimales de séparation et de détection, l’influence de la nature et de la concentration d’un agent d’appariement d’ions tel que le HFBA ou le PFPA, introduit dans la phase mobile, a pu être évaluée sur une colonne analytique en chromatographie de phase inversée de type C18. Plusieurs paramètres ont été pris en compte et étudiés lors de l’élaboration de la méthode d’extraction tels que la nature du solvant d’extraction, le pH, l’étape d’hydrolyse acide, l’efficacité de l’extraction par ultrasons et enfin la purification de l’extrait avant injection. La méthode développée a ensuite été validée suivant les recommandations de la Décision de la Commission Européenne (CE) No 2002/657 puis a subi une étape de validation supplémentaire en participant à une comparaison inter-laboratoire organisée sur des matériaux de miel contaminés et gérée par un organisme extérieur accrédité suivant la norme ISO17043. Par la suite, une démarche de transfert de la méthode analytique validée en CL-SM/SM a été mise en place pour son utilisation en chromatographie liquide couplée à la spectrométrie de masse à haute résolution (CL-SMHR). Une validation de cette démarche a été menée par l’application d’une étude statistique descriptive basée sur la notion de profil d’exactitude. Finalement, un programme expérimental de surveillance a été entrepris sur une série d’échantillons de divers miels collectés sur des marchés locaux pour tester la qualité des produits commercialisés au Liban. Contrôlés au regard de leur contamination en résidus d’antimicrobiens en CL-SM/SM parmi la trentaine de molécules prédéfinies dans l’étude, la positivité et/ou la non-conformité de certains échantillons ont pu être confirmées par l’utilisation de la CL-SMHR. / A new, simple and rapid method has been developed for the determination of multiclass antimicrobial residues in honey (sulfonamides, tetracyclines, macrolides, lincosamides and aminoglycosides). All the compounds were extracted from honey within single extraction method and analyzed by liquid chromatography - tandem mass spectrometry (LC-MS/MS) operating in positive electrospray ionization mode. In our study, we examined the behavior of volatile perfluorinated carboxylic acids (HFBA and PFPA) used as ion-pairing reagents for the separation of multiclass of antibiotic residues by reversed phase Zorbax SB C18 column. Furthermore, the extraction and clean-up steps were investigated and optimized by using ultrasonic-assisted extraction and dispersive solid phase extraction (d-SPE). Different parameters affecting the extraction efficiency including type of solvent, pH, breaking efficiencies of N-glycosidic linkage by hydrochloric acid, ultrasonic extraction and its duration compared to shaking technique, along with dispersive SPE clean-up were examined prior sample injection. The method was then validated according to European Commission Decision (EC) No 2002/657. Furthermore, the method was tested for its validity through participation in proficiency testing scheme organized by FAPAS for the analysis of tetracycline in honey. Afterwards, a transfer of the validated LC-MS/MS analytical method has been applied for the determination of antimicrobial residues in honey from low resolution to High Resolution Mass Spectrometry (HRMS). For that purpose, descriptive statistical approach was performed to assess the performance of the method based on simultaneous evaluation of the trueness and the intermediate precision. Finally, the method was applied for the determination of antimicrobial residues in honey collected from local markets at different regions in Lebanon. Positive samples were then analyzed by the LC-HRMS to confirm the presence of analytes detected by LC-MSMS.

[Truncated abstract] Salinity and waterlogging interact to reduce the growth of most crop and pasture species. Species that are productive on saline-waterlogging land are needed for Australian farming systems. One option is Lotus tenuis, a perennial legume widely grown for pasture in the flood-prone and salt-affected Pampa region of Argentina. To identify mechanisms responsible for the adverse interaction between salinity and waterlogging, Lotus tenuis with a reputation for tolerance was compared with L. corniculatus, the most widely cultivated Lotus species. The physiology of salt and waterlogging tolerance in L. tenuis (4 cultivars) was evaluated, and compared with L. corniculatus (3 cultivars). Overall, L. tenuis cultivars accumulated less Na+ and Cl-, and more K+ in shoots than L. corniculatus cultivars, when exposed to 200 mM NaCl for 28 d in aerated or in anoxic (stagnant agar) solutions. In a NaCl dose response experiment (0 to 400 mM NaCl in aerated solution), Lotus tenuis (cv. Chaja) accumulated half as much Cl- in its shoots than L. corniculatus (cv. San Gabriel) at all external NaCl concentrations, and about 30% less shoot Na+ in treatments above 250 mM NaCl. Ion distributions in shoots were determined for plants at 200 mM NaCl; L. tenuis (cv. Chaja) accumulated about half as much Cl- in old leaves, young leaves and stems, compared with concentrations in L. corniculatus (cv. San Gabriel). There were not, however, significant differences between the two species for Na+ concentrations in the various shoot tissues under aerated NaCl treatment. '...' Therefore, during early stages of exposure to salinity, L. tenuis accumulated a higher proportion of total Na+ in the roots under combined stagnant-plus-NaCl treatment (55% versus 39% for L. corniculatus). Na+ transporters, particularly those relying on H+ gradients across membranes, which in turn require adequate ATP levels, could be impaired under O2 deficits that inhibit respiration. To study the effect of O2 deficiency on a Na+ transporter, an NHX1-like gene was cloned from L. tenuis and identity established via sequencing and yeast complementation studies. Real-time qPCR showed expression of NHX1 in L. tenuis roots increased under stagnant-plus-NaCl treatment, whereas it was reduced in L. corniculatus. Thus, maintaining O2 transport to roots, together with up-regulation of an NHX1-like gene for Na+ accumulation in vacuoles, contributes to tolerance of L. tenuis to combined salinity and waterlogging stresses. This study highlights the importance of minimising Cl- transport to shoots as a mechanism of salt tolerance and has identified a CCC-like gene in L. tenuis as a candidate for mediating root-to-shoot Cl- transport. Under combined stagnant-plus-NaCl treatment, control of Na+ transport is another mechanism contributing to tolerance in these Lotus species. Enhanced root aeration in L. tenuis maintains root Na+ transport processes, such as accumulation in vacuoles via NHX1-like genes, to diminish xylem loading to the shoot. Overall, this thesis has contributed new knowledge on the potential of Lotus tenuis as a saltland pasture and has significantly enhanced current understanding on the mechanisms of salinity and waterlogging tolerance in plants.

Wide band gap semiconductors ZnO/GaN attracted a great deal of interests for decade, due to their wide direct band, high electron binding energy, excellent chemical and thermal stability, good heat conductivity and capability, high electron mobility and transparent properties at room temperature. They have many potential applications such as laser, biosensor, piezoelectric power generator, nano-electromechanical systems and flat panel field emission displays. However, unexpected contact loading during processing or packaging may induce residual stresses and/or an increase in defect concentration in ZnO/GaN wafer or thin film, causing possible degenerated reliability and efficient operation of the piezoelectric and photonic device. To ensure and improve the performance of devices based on ZnO/GaN, a better understanding of the mechanical/optoelectronic response under different processing and loading conditions and even the measuring methods are necessary. In this thesis, our aim is to reveal a comprehensive investigation of the mechanical responses on polar/non-polar GaN/ZnO single crystal under low dimensional stress. We try to provide the fundamental theoretical and experimental studies for further application and researches, such as tension testing, residual stress, low temperature cathodoluminescence and Raman spectroscopy analysis. In this study, the theoretical Young¡¦s modulus and Poisson ratio of ZnO/GaN are extracted from elastic constants for comparison and further estimation. The nano-scaled mechanical properties, such as Young¡¦s modulus, hardness and yield stress, are identified by using the nanoindentation system. The experimental values were fitting by the Hertzian contact theory. The results are in good agreement with the theoretical predictions. No significant strain rate influence is observed over the strain rate from 1x10-2 s-1 to 1x10-4 s-1. The comparisons of mechanical properties between the polar and non-polar planes of ZnO are firstly examined. The results reveal that the non-polar planes are softer than the polar plane. Both a-plane and m-plane ZnO have lower hardness and yield stress than c-plane ZnO. The microstructure and deformation mechanism are analyzed by using X-TEM and SEM. No pop-out or slope changing was found in their load-displacement curves, suggesting no phase transformation, twining or crack domain deformation occurred under microcompression and nanoindentation testing. Taking all considerations for the higher resulting Schmid factor and lower Burgers¡¦ vector, the most possible slip system for c-plane hexagonal structures is the pyramidal plane. The a-plane has shorter burger¡¦s vector on the slip plane which leads the lower yield stress than c-plane. To erase the effect of FIB induced Ga ion implantation, the c-plane ZnO was annealed at 900oC for 1 hour. We found that the yield stress under microcompression decreases and the intensity of the cathodoluminescence spectrum increases after the annealing process. This result indicates that the thermal treatment is a good way to refine the crystal quality and decrease the defects density. The E2 peak of Raman spectrometer exhibits high residual compression stress constrain in the c-plane GaN thin film. Due to the high surface/volume ratio of pillar, nil residual stress remains in the GaN pillar after the FIB milling process. Even after the yield point, nil residual stress remains in the c-GaN pillar. Results indicate that the one dimensional geography is a good way to erase residual stress.

A Cl stable isotope fractionation factor between amphibole and fluid has been determined at 700 °C and 0.2 GPa. Rates of isotope exchange between pargasite and water at 600-800 °C were slow; therefore synthesis of amphibole in the presence of a fluid was necessary to facilitate the incorporation of Cl into amphibole. Hastingsite was synthesized from an oxide mixture and reacted with a NaCl-bearing supercritical fluid for periods of 3 to 14 days, approximately at the wüstite-magnetite buffer. Based on these synthesis-reaction experiments, the fractionation between hastingsite and a NaCl-bearing solution (~20000 ppm Cl) at 700 °C is 103lnαamphibole-fluid = 0.19‰ ± 0.23‰. These data display near zero fractionation at 700 °C, but suggest that amphibole is slightly enriched in 37Cl relative to the fluid, in agreement with empirical and theoretical results. / text

Red rice (Oryza spp.) is one of the main limiting factors to rice (O. sativa L.) yield. After several decades searching for red rice control tools, it was developed imidazolinone tolerant rice, to selectively control red rice. To better understand this technology it were conducted two experiments in 2004/05, in Santa Maria, Rio Grande do Sul state, Brazil. The first experiment (Chapter I) had the objective of: 1) evaluate red rice control by imidazolinone herbicides in Clearfield rice; 2) evaluate the imidazolinone herbicide carryover effect on rygrass and non-tolerant rice (IRGA 417) and 3) evaluate the outcrossing rates between Clearfield rice and red rice. The herbicides tested control red rice. Although injury to Clearfield rice was observed, the herbicide did not affected yield. It was observed herbicide carryover to non-tolerant rice, reducing plant stand. There was natural outcrossing between Clearfield rice and red rice, at rates of 0.065%. The second experiment (Chapter II) had the objective of evaluate the herbicide Only® (imazethapyr 75 g L-1 + imazapic 25 g L-1) in different application rates and timing on two genotypes, IRGA 422 CL and Tuno CL, to the imidazolinones herbicides. When compared with the cultivar, the hybrid was more tolerant to the herbicide Only®. It was possible to apply rates of up to 2.0 L ha-1 in the hybrid, without affecting rice yield. Red rice control was total with split application of Only® in PRE and POST, with rates above 1.25 L ha-1. The most efficient treatment was with application of 0.75 L ha-1 in PRE followed by 0.5 L ha-1 in POS, because, it was the lowest rate that promoted 100% control, with relatively low toxicity to the cultivar and without affecting rice yield. / O arroz-vermelho (Oryza spp.) é um dos principais fatores limitantes da produtividade de grãos do arroz irrigado (O. sativa L.). Após várias décadas de busca de alternativas para o controle seletivo do arroz-vermelho, desenvolveram-se genótipos de arroz tolerante a herbicida do grupo químico das imidazolinonas, o qual controla eficiente e seletivamente esta planta daninha. Para estudar e melhor entender esta tecnologia, conduziu-se dois experimentos em Santa Maria-RS no ano agrícola 2004/05. O primeiro experimento (Capítulo I) teve como objetivos: 1) avaliar a eficiência do controle de arroz-vermelho com o herbicida Only? (imazethapyr 75 g L-1 + imazapic 25 g L-1), 2) avaliar o residual do herbicida no solo através dos danos causados no azevém e em arroz não tolerante e 3) avaliar a taxa de ocorrência de cruzamento natural entre o arroz-vermelho e o arroz cultivado. O herbicida testado controla eficientemente o arroz-vermelho em arroz tolerante. Embora tenha-se observado fitotoxicidade, não houve redução na produtividade da cultivar tolerante. O estande inicial da cultivar IRGA 417 é afetado pelo residual do herbicida presente no solo. Ocorre cruzamento natural entre o arroz-vermelho e o arroz cultivado, sendo que a taxa de ocorrência obtida no experimento foi de 0,065%. O segundo experimento (Capítulo II) teve como objetivo avaliar o controle de arroz-vermelho e o desempenho de dois genótipos de arroz irrigado, IRGA 422 CL e Tuno CL, tolerantes a herbicidas do grupo das imidazolinonas a doses e épocas de aplicações do herbicida Only? , em áreas com alta infestação de arroz-vermelho. Constata-se que o híbrido é mais tolerante ao herbicida Only? , quando comparado à cultivar IRGA 422 CL, sendo possível a utilização de dose total de até 2,0 L ha-1 no híbrido, em áreas com alta infestação de arroz-vermelho, sem afetar a produtividade. O controle de arroz-vermelho é total com aplicação fracionada do herbicida em pré e pós-emergência (PRE + POS), desde que o total aplicado não seja inferior a 1,25 L ha-1. Esta condição é atendida pelo tratamento com 0,75 L ha-1 em PRE mais 0,5 L ha-1 em POS, o qual propicia a menor dose total dentre aqueles com 100% de controle, não afetando a produtividade e com fitotoxicidade semelhante ao tratamento com 1,0 L ha-1 em POS, utilizado como referência.

TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN FINANZAS / Laura Benguechea G. [Parte I mediante método de los múltiplos], Paula Castro C. [ Parte II mediante método de flujos de caja descontado] / El presente proyecto de grado, tiene como objetivo la estimación de la valorización económica de la empresa E-CL S.A. mediante el método de "valorización por múltiplos", con el fin de determinar el precio objetivo de la acción en un determinado período. En la primera etapa se analizó la empresa objetivo con la finalidad de conocer los productos y/o servicios que ofrece, características del sector al que pertenece, el mercado donde opera, estructura de la organización, directorio, políticas de la empresa y participaciones en otras compañías. En la segunda etapa de la valoración se seleccionó las compañías que son comparables para esto se analizó si cotizan en bolsa, realizan la misma actividad que la empresa objetivo, tienen similares productos y/o servicios, pertenecen al mismo país o zona geográfica, y si tienen similares tamaños (volumen de ventas, volumen de gastos, etc.). En la tercera etapa se calcularon los múltiplos de ganancias, valor libro e ingresos tanto para la empresa objetivo como para las empresas comparables. En la etapa final se aplicó los resultados a la empresa objetivo y se seleccionó un rango de valoración, para esto se seleccionó la media de los ratios calculados para las empresas comparables y se multiplicaron por los datos correspondientes de la empresa objetivo, una vez obtenidos los valores obtenidos se seleccionó el rango de valoración final, por lo tanto a través del método de valoración por múltiplos, el rango de valor para la compañía E.CL al 30 de junio de 2014 debiera estar entre $952 y $2.015 por acción. / El presente proyecto de grado, tiene como objetivo la estimación de la valorización económica de la empresa E-CL S.A. mediante el método de "valorización por Flujos de Caja Descontados", con el fin de determinar el precio objetivo de la acción en un determinado período. En la primera etapa se analizó la empresa objetivo con la finalidad de conocer los productos y/o servicios que ofrece, características del sector al que pertenece, el mercado donde opera, estructura de la organización, directorio, políticas de la empresa y participaciones en otras compañías. En la segunda etapa, se estimara una tasa de descuento o Costo de Capital de la empresa para posteriormente realizar una proyección del Estado de Resultado del período junio de 2014 hasta el año 2019. Con la proyección de los flujos y la tasa de descuento, se determinara el valor económico del patrimonio de la compañía, con el cual podremos determinar precio de la acción de E-CL al 30 de junio de 2014, precio que se comparara con el valor de mercado del precio de la acción al 30 de junio de 2014. La tasa Costo de Capital considerará en una primera instancia la información propia de la empresa del período 2010 a septiembre 2014, luego esta tasa se apalancará a la estructura de capital objetivo. El resultado de la tasa Costo de Capital Promedio Ponderado (WACC, siglas en inglés) resulta de 8,8437%, la cual es razonable para este tipo de empresa en etapa madura. Para determinar las proyecciones del Estado de Resultado y de Flujos de Caja se consideraran supuestos del mercado, como crecimiento de demanda de la electricidad, costos asociados con las proyecciones de ventas, precios de combustibles, nivel de inversiones en activos fijos, en reposición y en capital de trabajo. Las fuentes de información se obtendrán tanto de entidades gubernamentales como privadas. Para estimar el valor económico del período posterior al de análisis.

No description available.

Existem muitos tipos de substâncias orgânicas e inorgânicas que podem apresentar efeito tóxico ou inibidor aos organismos dos sistemas aeróbios de tratamento de efluentes, e entre essas substâncias está o cloreto. Nos efluentes, os cloretos se apresentam na forma de algum tipo de sal, e o mais comum é o cloreto de sódio. O cloreto de sódio pode ser encontrado em vários tipos de efluentes como, por exemplo, efluentes de indústrias alimentícias, petrolíferas, de processamento de couro e no lixiviado de aterros sanitários. Os cloretos podem além de prejudicar a microbiota, interferir no método de determinação da Demanda Química de Oxigênio - DQO e da Demanda Bioquímica de Oxigênio - DBO, que são parâmetros comumente utilizados para controle operacional de estações de tratamento. O presente trabalho teve como objetivo estudar a influência da adição de cloretos em um sistema de tratamento aeróbio por lodos ativados de bancada, que foi avaliado com base na remoção de matéria orgânica e no desenvolvimento e interação da microbiota envolvida. Foi avaliado o efeito tóxico da adição de concentrações de cloreto variando de 0 a 16 g\'CL POT. -\'/L. Os resultados confirmaram que há uma perda significativa de eficiência de remoção de matéria orgânica, principalmente quando a concentração de cloretos é superior a 4 g\'CL POT. -\'/L. Observou-se também que determinadas concentrações de cloretos são tóxicas aos organismos e prejudicam a estrutura dos flocos biológicos. Além disso, concluiu-se que a determinação da DQO pelo método 5220D do Standard Methods for Examination of Water and Wastewater sofre, em alguns casos, a interferência do cloreto e portanto pode não ser o melhor parâmetro para avaliação de eficiência dos sistemas de tratamento que operam sob essa condição. / There are many types of organic and inorganic substances that may have toxic effect on microorganisms of aerobic systems for wastewater treatment, and among these substances is the chloride. In the effluents, the chlorides are in the form of some type of salt, and most common is sodium chloride. Sodium chloride can be found in various types of effluents, for example, effluents from food industries, oil, leather processing and leachate from landfills. The chlorides can also affect the microbiota, interfering with the method of determining the Chemical Oxygen Demand - COD and the Biochemical Oxygen Demand - BOD, which are commonly used parameters for operational control of treatment plants. This work aimed to study the influence of the addition of chlorides in a system of aerobic activated sludge bench, which was evaluated based on the removal of organic matter and the development and interaction of microorganisms involved. We evaluated the toxic effect of adding chloride concentrations ranging 0-16 g\'CL POT. -\' /L. The results confirmed that there is a significant loss of removal efficiency of organic matter, especially when the chloride concentration is more than 4 g\'CL POT. -\'/L. It was also noted that certain concentrations of chloride are toxic to microorganisms and affect the structure of biological flocs. Furthemore, it was concluded that the determination of COD by 5220D method of Standard Methods for Examination of Water and Wastewater suffers, in some cases, interference of chloride and maybe not the better parameter for evaluating efficiency of treatment systems that operate under this condition.

Made available in DSpace on 2015-04-14T13:35:39Z (GMT). No. of bitstreams: 1 447433.pdf: 1084376 bytes, checksum: 6e6c93e4b9ee50a3d7f69bfd07cc16b1 (MD5) Previous issue date: 2012-12-21 / Oral anticoagulation has been shown to be effective in the prevention and treatment of thromboembolic events. Vitamin K antagonists (VKA) are the drugs of choice for over 50 years in treatment for prevention of thromboembolic events and the most commonly used are warfarin and phenprocoumon. Currently there are new oral anticoagulants, the direct factor Xa inhibitors, and direct thrombin inhibitors which demonstrate similar efficacy to VKA and low bleeding risk and do not require monitoring because they have low interaction with other drugs and foods. Despite these advantages, the AVK still widely used due to the long experience of its use, the possibility of monitoring through the control of international normalized ratio (INR), the existence of an antidote to reverse its effect (vitamin K) and at low cost . The main difference between the AVK is pharmacological half-life, which is shorter for warfarin, approximately 30 hours versus 216 hours for phenprocoumon. There are few data in the literature that compare the efficacy, stability and drug interactions of these two drugs. Changes in therapeutic levels of AVK and the difficulty of keeping it stable due to interactions with drugs and food is a limiting factor for the efficacy and safety of these drugs. Due to the lack of evidence comparing the stability of the therapeutic level of warfarin and phenprocoumon, it is necessary that studies comparing these two drugs in relation to maintaining therapeutic level of anticoagulation. / A anticoagula??o oral tem se mostrado efetiva na preven??o e no tratamento de eventos tromboemb?licos. Os antagonistas da vitamina K (AVK) s?o as drogas de escolha a mais de 50 anos no tratamento para preven??o de eventos tromboemb?licos e os mais comumente utilizados s?o a varfarina e a femprocumona. Atualmente existem novos anticoagulantes orais, os inibidores diretos do fator Xa, e os inibidores diretos da trombina os quais demonstram efic?cia semelhante aos AVK e baixo risco de sangramento e n?o necessitam de monitoramento por apresentarem baixa intera??o com outras drogas e alimentos. Apesar dessas vantagens, os AVK continuam sendo amplamente utilizado devido ? longa experi?ncia de seu uso, possibilidade de monitoriza??o atrav?s do controle da raz?o normatizada internacional (RNI), pela exist?ncia de um ant?doto para revers?o de seu efeito (vitamina K) e pelo baixo custo. A principal diferen?a farmacol?gica entre os AVK ? sua meia-vida, a qual ? mais curta para a varfarina, aproximadamente 30 horas, versus 216 horas para a femprocumona. Existem poucos dados na literatura que comparem a efic?cia, estabilidade e intera??es medicamentosas dessas duas drogas. As varia??es dos n?veis terap?uticos dos AVK e a dificuldade de mant?-lo est?vel devido a intera??es com os medicamentos e com a alimenta??o ? um fator limitante da efic?cia e seguran?a dessas drogas. Devido ? aus?ncia de evid?ncias comparando a estabilidade do n?vel terap?utico entre a varfarina e femprocumona, ? necess?rio que existam estudos que comparem essas duas drogas em rela??o ? manuten??o de anticoagula??o em n?vel terap?utico.

Les classificateurs ga (cl. 16), ku (cl. 17) et mu (cl. 18) marquent respectivement les valeurs de « contact », de « distance » et d’« intériorité » : a) lorsqu’ils sont préfixés à la base ‑úma /endroit/ ; b) lorsqu’ils apparaissent dans le verbe conjugué ou préfixés aux thèmes des déterminants ; c) lorsqu’ils sont suivis d’un nom en isolation ; d) ou lorsqu’ils ils sont suivis d’un verbe.Bu (cl. 14) marque en outre une valeur « abstraite » lorsqu’il se combine avec des bases lexicales ; il exprime le temps, la comparaison et la cause, lorsqu’il est préfixé aux thèmes des déterminants ; il sert en troisième lieu à marquer l’hypothèse lorsqu’il est employé sous la forme d’un morphème libre. / Classifiers ga (cl. 16), ku (cl. 17) and mu (cl. 18) express respectively “contact”, “distance” and “interiority”: a) when they are prefixed by ‑úma /place/; b) when they appear in conjugated verbs or are prefixed by themes of determinants; c) when they are followed by a name in the form of a free morpheme; d) or when they are followed by a verb. Bu (cl. 14) expresses, in addition, “abstract” value when it is combined to lexical bases; when it is prefixed to the themes of determinants, it carries temporal, comparative and causal values; it serves thirdly to mark the hypothesis in the form of a free morpheme.