The aim of diploma thesis has been development and optimization of method determination of N- nitrososarcosine and N-nitrosoproline in malt by gas chromatography with chemiluminiscence detector. Optimization of extraction method has been performed by response surface method. Quantification has been performed by internal standard method (N-nitrosopipecolic acid, in which matrix effects has been studied. These has been verified in münchen and pilsen malt, therefore matrix-matched calibration has been constructed. The developed method has been aplicated on wheat, münchen and pilsen malt. N- nitrosoproline was detected only in münchen malt and in other cases has been under limit of detection (LOD=4,0 µg/kg). N-nitrososarcosine was in all cases under limit of detection (LOD=3,7 µg/kg). The matrix-matched calibration has been constructed for experimental münchen malt with N-nitrosoproline concentration at 13,2 ± 2,9 µg/kg. Powered by TCPDF (www.tcpdf.org)

In previous studies, we have isolated several marine indole alkaloids and evaluated them in the forced swim test (FST) and locomotor activity test, revealing their potential as antidepressant and sedative drug leads. Amongst the reported metabolites to display such activities was 5-bromo-N,N-dimethyltryptamine. Owing to the importance of the judicious introduction of halogens into drug candidates, we synthesized two series built on a 2-(1H-indol-3-yl)-N,N-dimethylethanamine scaffold with different halogen substitutions. The synthesized compounds were evaluated for their in vitro and in vivo antidepressant and sedative activities using the mouse forced swim and locomotor activity tests. Receptor binding studies of these compounds to serotonin (5-HT) receptors were conducted. Amongst the prepared compounds, 2-(1H-indol-3-yl)-N,N-dimethyl-2-oxoacetamide (1a), 2-(5-bromo-1H-indol-3-yl)-N,N-dimethyl-2-oxoacetamide (1d), 2-(1H-indol-3-yl)-N,N -dimethylethanamine (2a), 2-(5-chloro-1H-indol-3-yl)-N, N-dimethylethanamine (2c), 2-(5-bromo-1H-indol-3-yl)-N,N-dimethylethanamine (2d), and 2-(5-iodo-1H-indol-3-yl)-N,N -dimethylethanamine (2e) have been shown to possess significant antidepressant-like action, while compounds 2c, 2d, and 2e exhibited potent sedative activity. Compounds 2a, 2c, 2d, and 2e showed nanomolar affinities to serotonin receptors 5-HT1A and 5-HT7. The in vitro data indicates that the antidepressant action exerted by these compounds in vivo is mediated, at least in part, via interaction with serotonin receptors. The data presented here shows the valuable role that bromine plays in providing novel chemical space and electrostatic interactions. Bromine is ubiquitous in the marine environment and a common element of marine natural products.

Given a configuration of t indistinguishable pebbles on the n vertices of a graph G, we say that a vertex v can be reached if a pebble can be placed on it in a finite number of "moves". G is said to be pebbleable if all its vertices can be thus reached. Now given the n-path Pn how large (resp. small) must t be so as to be able to pebble the path almost surely (resp. almost never)? It was known that the threshold th(Pn) for pebbling the path satisfies n2clgn≤th(Pn)≤n22lgn, where lg=log2 and c<1/2 is arbitrary. We improve the upper bound for the threshold function to th(Pn)≤n2dlgn, where d>1 is arbitrary.

Les glycoconjugués comme les glycolipides et les glycopeptides sont impliqués dans de nombreux processus biologique, physiologique et pathologique, tels que les interactions cellule-cellule, les infections virales et bactériales, les réponses immunitaires, le cancer, etc. Ces propriétés ont suscité de recherche intensive pour la synthèse de mimes de glycoconjugés pour des applications en biologie et en pharmacie. Cette thèse est consacrée à la synthèse de glycolipides et de glycopeptides liés par la liaison N-oxyamide qui possède une meilleure stabilité métabolique et une facilité de formation de liaison H conduisant à des structures secondaires très intéressantes.Les dérivés de pyranoid glycoaminooxy acides fonctionnés en positions 2 et 6 du sucre sont synthétisés à partir du methyl alpha-D-glucopyranoside, puis transformés en N-oxyamide glycolipides. En tant que nouveaux mimes de glycoglycérolipides et glycosphingolipides, les N-oxyamide beta-glycolipides possédant une ou deux chaines lipidiques sont préparés à partir du glucose ou du galactose penta-acétate et de (S)-1,2-di-O-benzyl-glycérol.De plus, une synthèse stéréosélective de (2R) et de (2S)-3-beta-O-glycosyl aminooxy esters a été réalisée à partir du (2R)-beta-glycoglycérol, avec la réaction de Mitsunobu et l’épimérisation de Lattrell-Dax comme étapes clés. Les N-oxyamide glycopeptides ont pu être préparés à partir de glycosyl aminooxy esters orthogonalement protégés. / As part of glycoconjugate family, glycolipids and glycopeptides are involved in a variety of important biological, physiological and pathological processes, such as cell-cell interactions, viral and bacterial infections, immune response, cancer progression, etc. Synthesis of glycoconjugate mimics has attracted intensive research interest for biological and pharmaceutical applications. This thesis was devoted to the synthesis of N-oxyamide-linked glycolipids and glycopeptides, since N-oxyamide-containing compounds have shown improved metabolic stability, and interesting secondary structures due to the easy H-bond formation property of N-oxyamide compounds.From methyl alpha-D-glucopyranoside, the 2,6-functionalized pyranoid glycoaminooxy acid derivatives have been successfully prepared as a multifunctional building block for further derivatization to new N-oxyamide glycolipids. From glucose or galactose pentaacetate and (S)-1,2-di-O-benzyl-glycerol, we have successfully achieved the first synthesis of N-oxyamide-linked beta-glycolipids with one or two lipids chains, as novel mimics of glycoglycerolipids and glycosphingolipids.In addition, the (2R) and (2S)-3-beta-O-glycosyl aminooxy esters have been stereoselectively synthesized from (2R)-beta-glycoglycerol, with Mitsunobu reaction and Lattrell-Dax epimerization as key steps. N-Oxyamide-linked glycopeptides have been prepared from the orthogonally protected glycosyl aminooxy esters.

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The main objective of this project is the study of heterogeneous metallic catalysts for the production of fine chemicals and elimination of ultra low concentration of ethylene with horticultural applications. Development of new active and selective catalysts in industrial processes has been possible due to a simultaneous application of rational design catalysts and characterization techniques of materials. With this purpose, heterogeneous metallic catalysts with properties to reduce selectively nitro groups when other sensitive functions are present have been developed. Monometallic and bimetallic Pt and Au catalysts were estudied in reductive coupling reactions with nitrocompunds, aldehydes and H2 which have allowed to evaluate variables as support effect, solvent, metal promoter and intensity of heat treatment on their catalytic behavior.The proposed procedure offers an efficient and sustainable alternative for the production of nitronas, imines or secondary amines through a metal heterogeneous catalysts that does not require the use of soluble, often toxic, additives. On the other hand, it has been shown that silver supported on zeolite is able to adsorb high amounts of ethylene in ultra low concentrations in air (10 ppm). Taking this into account, the influence of concentration of active species according with framework used was investigated. The influence of molecules, such as H2O or CO2, in competition for the active sites on the adsorption of ethylene was studied in order to optimize their behavior in processes of adsorption of trace amounts of ethylene with horticultural applications. / La presente tesis doctoral tiene como principal objetivo el estudio de catalizadores metálicos heterogéneos para la obtención de productos de química fina y la eliminación de trazas de etileno por adsorción con aplicaciones hortícolas. Gracias a la aplicación simultánea de técnicas de diseño racional de los catalizadores y a técnicas de caracterización fundamental de los materiales, ha sido posible el desarrollo de nuevos catalizadores activos y selectivos en procesos de interés industrial. Con este fin, se han desarrollado catalizadores metálicos heterogéneos con propiedades exclusivas para hidrogenar quimioselectivamente grupos nitro en presencia de otros grupos funcionales reducibles. El estudio de catalizadores monometálicos y bimetálicos de Pt, Au soportados para reacciones de acoplamiento reductivo de nitrocompuestos, aldehídos e H2 ha permitido evaluar la influencia de las principales variables de síntesis de los materiales sobre su comportamiento catalítico, incluyendo el efecto del tipo de soporte utilizado, el disolvente empleado, la introducción de diferentes promotores metálicos y la intensidad del tratamiento térmico realizado. El procedimiento propuesto ofrece una alternativa eficiente y sostenible para la producción industrial de nitronas, iminas y/o aminas secundarias mediante el uso de catalizadores metálicos heterogéneos que no requieren el uso de aditivos tóxicos. Por otra parte, se ha mostrado que plata soportada sobre zeolitas es capaz de adsorber elevadas cantidades de etileno en concentraciones de 10 ppm en aire. Así, se ha estudiado la influencia de la estructura zeolítica empleada en la concentración de especies activas para la adsorción de etileno, en adsorbentes Ag-zeolita. Con el fin de optimizar su comportamiento en procesos de adsorción de trazas de etileno con aplicaciones horticulturales se ha estudiado la influencia de moléculas, como H2O y/o CO2, en la competencia por los sitios activos en la adsorción de etileno. / Aquesta tesi doctoral té com a principal objectiu l'estudi de catalitzadors metàl¿lics heterogenis per a l'obtenció de productes de química fina i l'eliminació de traces d'etilÿ per adsorció amb aplicacions hortícoles. Gràcies a l'aplicació simultània de tÿcniques de disseny racional dels catalitzadors i a tÿcniques de caracterització fonamental dels materials, ha sigut possible el desenvolupament de nous catalitzadors actius i selectius en processos d'interÿs industrial. S'hi han desenvolupat catalitzadors metàl¿lics heterogenis amb propietats exclusives per a hidrogenar quimioselectivament grups nitro- en presÿncia d'altres grups funcionals reduïbles. L'estudi de catalitzadors monometàl¿lics i bimetàl¿lics de Pt, Au, suportats per a reaccions d'acoblament reductiu de nitrocompostos, aldehids i H2, ha permÿs avaluar la influÿncia de les principals variables de síntesi dels materials sobre el seu comportament catalític, inclòs l'efecte del tipus de suport utilitzat, el dissolvent emprat, la introducció de diferents promotors metàl¿lics i la intensitat del tractament tÿrmic. El procediment proposat ofereix una alternativa eficient i sostenible per a la producció industrial de nitrones, imines i/o amines secundàries mitjançant l'ús de catalitzadors metàl¿lics heterogenis amb propietats exclusives per a hidrogenar quimioselectivament grups nitro- en presÿncia d'altres grups funcionals reduïbles. D'altra banda, s'hi ha mostrat que la plata sobre zeolites és capaç d'adsorbir elevades quantitats d'etilÿ en concentracions de 10 ppm en aire. Així, s'ha estudiat la influÿncia de l'estructura zeolítica emprada en la concentració d'espÿcies actives per a l'adsorció d'etilÿ, en adsorbents Ag-zeolita. Amb l'objectiu d'optimitzar-ne el comportament en processos d'adsorció de traces d'etilÿ amb aplicacions horticulturals, s'ha estudiat la influÿncia de molÿcules, com ara H2O i/o CO2, en la competÿncia pels llocs actius en l'adsorció d'etilÿ. / Cisneros Reyes, LY. (2017). Metales Soportados para Síntesis de Nitronas y Adsorción de Etileno en corrientes de Aire [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90434

Nitrogen recovery and contribution to production agricultural systems are critical services provided by cover crops investigated in this study. Research was conducted to evaluate the effect of simulated residual N (SRN) on N recovery in various winter cover crop systems (CCS) and subsequent effects on corn N uptake. Biomass, C and N measurements, 15N recovery, and sources of N acquisition were quantified among CCS. Subsequently, CCS and SRN effects on corn productivity and N status were quantified. Grass-included CCS had the greatest N scavenging ability by CCS termination, though they had negative or neutral effects on corn N acquisition. Brassicas-included CCS were prolific early season N scavengers, though winterkill may have negated this effect. Legumes-included CCS generally accumulated large quantities of N and had narrow C:N ratios, positively affecting corn N acquisition. This study highlights the importance of context-specific CCS selection for N conservation.

African languages / D.Litt. et Phil.

Luktämnen i omgivningen kan utgöra distraktorer som försämrar den kognitiva prestationen. Detta gör luktens påverkan till en viktig arbetsmiljöfråga. De flesta vänjer sig vid lukter i omgivningen – de habituerar. Men ibland sker inte denna tillvänjning. Syftet var att undersöka ifall det finns ett samband mellan skillnad i habituering till ett luktämne och arbetsminne och inhibering. En grupp av 40 individer i åldrarna 19 till 64 exponerades för n-butanol under 45 minuter. Deltagarna gjorde upprepade skattningar av luktämnets intensitet och delades in i grupperna: icke-habituerare och habituerare. Före och under exponeringen utförde deltagarna 3-back, ämnat att mäta arbetsminne, och Stroop, ämnat att mäta inhibering. Gruppen icke-habituerare tenderade att prestera sämre på 3-back både före och under exponeringen. Oförmåga till habituering kan vara ett beteendeuttryck för sämre arbetsminneskapacitet och eventuellt andra sårbarhetsfaktorer. Dessa faktorer bör undersökas vidare. / Odorants in the environment can serve as distractors that impair cognitive performance. The impact of odors constitute an important occupational health issue. Most people get used to smells in the environment – they habituate. But occasionally habituation does not occur. The aim was to investigate whether there is a correlation between difference in habituation to an odorant and working memory and inhibition. A group of 40 individuals between the ages of 19 to 64, were exposed to n-butanol for 45 minutes. Participants made repeated ratings of intensity of the odorant. Two groups were created based on non-habituation and habituation. Before and during the exposure, the participants performed 3-back, used to measure working memory, and Stroop, used to measure inhibition. The group who did not habituate showed a tendency to perform worse on 3-back, before and during exposure. Inability to habituate may be a behavioral expression of poorer working memory capacity, and possibly other vulnerability factors. These factors should be further investigated.