2,314 research outputs found
Occurrence of Cranocrinus Wanner in North America
No full textThe cladid inadunate genus Cranocrinus Wanner is typically from Upper Permian rocks of the Island of Timor, Indonesia, and has been reported from Lower Permian rocks of the Ural Mountains of Russia. Arendt (1970) has demonstrated that juvenile C. praestans lacks radials (is pseudomonocyclic) while adult specimens have radials (are dicyclic). Both conditions are noted for C. eximius n. sp. from Morrowan (Lower Pennsylvanian) rocks of Oklahoma and are described herein. Possible methods of feeding and respiration are considered in the discussion of Cranocrinus
Efeito da aplicação de fosfito de potássio na biossíntese de metabólitos durante o cravo (Dianthus caryophyllus L.) - Fusarium oxysporum f. sp. dianti
No full textilustraciones, diagramas, fotografías, gráficas, tablasEn la presente investigación se estudió el efecto que tiene la aplicación de una disolución al 3% de fosfito de potasio en la bioquímica de raíces de clavel durante la inducción de resistencia al patógeno Fusarium oxysporum f. sp. dianthi. Si bien las disoluciones de fosfito de potasio han sido usadas como fertilizantes, fungicidas sistémicos o activadores de defensa natural, para el caso del cultivo del clavel, su uso ha sido limitado y existen solo algunos reportes recientes sobre su papel como inductor de resistencia. Es por ello que, con el fin de profundizar en los procesos involucrados en la acción de este inductor, en la presente investigación, aplicando herramientas de análisis metabolómico no dirigido, se estudiaron los metabolitos que se acumulan en raíces de la planta por acción de este inductor de resistencia y se estudió la expresión de genes asociados con algunos de los metabolitos de interés. Para ello, en una primera etapa se llevó a cabo un ensayo in vivo donde se seleccionó la estrategia para la aplicación de la disolución de fosfito en el suelo. Posteriormente, se realizó la obtención del perfil metabólico mediante GC-MS, con previa derivatización con agente sililante; en este punto se identificaron metabolitos diferenciables para los tratamientos estudiados, entre los cuales se destacan algunos aminoácidos, carbohidratos y ácidos orgánicos, entre otros. Estos resultados indicaron que mecanismos como el metabolismo de aminoácidos, transporte de nitrógeno, metabolismo de carbohidratos y señalización en plantas, son importantes en la inducción de resistencia. Finalmente, en una tercera etapa se estudiaron los niveles transcripcionales de los genes p5cr y npr1, los cuales participan en la biosíntesis de prolina y en la activación de RSA (Resistencia Sistémica Adquirida), respectivamente. Se encontró que la aplicación del inductor generó un aumento en los niveles transcripcionales de dichos genes en la variedad susceptible, confirmando a nivel molecular la activación de las rutas estudiadas en este fenómeno biológico. Los hallazgos encontrados en esta investigación permiten sugerir que el uso de fosfito de potasio, en su rol de inductor de resistencia, potencializa la síntesis de metabolitos asociados a defensa vegetal, muy probablemente asociada a la activación de RSA dependiente de ácido salicílico. (Texto tomado de la fuente)In the present study, the effect of 3% potassium phosphite solution on the carnation root biochemistry during the resistance induction to the pathogen Fusarium oxysporum f. sp. dianthi was evaluated. Although potassium phosphite solutions have been used as fertilizers, systemic fungicides, or natural defense activators, in the case of carnation cultivation, their use has been limited, and there are only a few recent reports on their role as a resistance inducer. Therefore, to deepen the processes involved in the action of this inducer, in the present investigation, applying untargeted metabolomics-based analysis tools, those metabolites differentially accumulated in plant roots due to the action of this resistance inducer, as well as the expression of genes associated with some of the top-ranked metabolites, were studied. In this regard, the first stage involved an in vivo test where the strategy for applying the phosphite solution in the soil was selected. Subsequently, the metabolic profile was obtained by GC-MS, with prior derivatization with a silylating agent. At this point, differentiable metabolites were identified for the studied treatments, among which some amino acids, carbohydrates, and organic acids, among others, were statistically recognized. These results indicated that mechanisms such as amino acid metabolism, nitrogen transport, carbohydrate metabolism, and plant signaling are relevant for resistance induction. Finally, the third stage comprised the evaluation of transcriptional levels of the p5cr and npr1 genes, which participate in proline biosynthesis and ASR (Acquired Systemic Resistance) activation, respectively. It was found that the inducer application generated a transcriptional level increase in the test genes for the susceptible carnation variety, confirming at the molecular level the activation of those pathways studied in this biological phenomenon. The findings in this research suggest that the use of potassium phosphite, in its role as a resistance inducer, potentiates the synthesis of metabolites associated with plant defense, most likely associated with salicylic acid-dependent ASR activation.Florval QFC. - Ente encargada de proveer los esquejes
Universidad Militar Nueva Granada - Ente con los equipos analíticos usadosMaestríaMagíster en Ciencias - BioquímicaPerfilado metabólico mediante metabolómica no dirigida, usando GC-MS.Bioquímica de las interacciones Hospedero – Patógen
L-Arginine deficiency and supplementation in experimental acute renal failure and in human kidney transplantation
No full textL-Arginine deficiency and supplementation in experimental acute renal failure and in human kidney transplant recipients.BackgroundThe “L-arginine paradox” refers to situations where L-arginine (L-Arg) supplementation stimulates nitric oxide (NO) synthesis, despite saturating intracellular concentrations. This paradox is frequently observed in acute renal failure (ARF). First, the effects of L-Arg on renal function of rats with ARF were studied. Based on the promising results from these initial studies, the second part of our study searched for a form of ARF in humans that could be studied easily under conditions with little variance and yet was linked with endothelial dysfunction. Thus, we investigated the effects of L-Arg supplementation immediately after kidney transplantation in 54 patients.MethodsIn uranyl nitrate-induced ARF in rats the effects of L-Arg and L-NNA (inhibitor of nitric oxide synthase; NOS) on glomerular filtration rate (GFR), renal plasma flow (RPF), blood pressure (BP) and NOx (NO2-+NO3-) excretion were examined. Tissue L-Arg levels, NOS activities, immunodetection of NOS and superoxide dismutase (SOD), activities of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and xanthine oxidase, and nitrotyrosine immunoreactive protein (NT-IR) were determined and compared to sham operated animals. Secondly, in a randomized, double-blind study, the effects of L-Arg on GFR and RPF were investigated in 54 kidney transplant recipients, receiving IV L-Arg for three days. GFR and RPF were measured on days 1, 3, 5 and 10 by scintigraphy.ResultsIn experimental ARF, decreased RPF and GFR were associated with reduced tissue L-Arg levels, endothelial NOS-III expression, NO formation and NOx excretion. Reduction in GFR, RPF and NOx excretion were reversed upon administration of exogenous L-Arg. There also was a loss of Cu,Zn-SOD, a key enzyme against oxidative stress, and an elevation of NT-IR, an indicator of nitrosative stress and suggested marker for pathological actions of NO. However, NT-IR was not dependent on de novo NO synthesis and not related to the functional effects of L-Arg administration. In kidney transplant recipients receiving organs with a short cold ischemia time (CIT) and from young donors, that is, those with a higher likelihood of a functional endothelium, early administration of L-Arg improved renal function.ConclusionBoth experimental and clinical data show that L-Arg deficiency and endothelial dysfunction are pathomechanistically relevant in ARF. The data suggest a therapeutic potential for the administration of L-Arg in ARF and kidney transplantation, at least in patients receiving kidneys with shorter CIT and from younger donors
Brandi Olsen as Jr Queen 1st Attendant in front, From L to R: Jr Queen 2nd Attendant Savannah Straatman, Queen 1st Attendant Tori Wanner, Jr Queen Janessa Gardener, Queen 2nd Attendant Shyann Andrus, Queen Taylor Hymas
No full textColor photograph of Cache County royalty in front of an old stone wall. Picture taken for social media highlight. Brandi Olsen as Jr Queen 1st Attendant in front, From L to R: Jr Queen 2nd Attendant Savannah Straatman, Queen 1st Attendant Tori Wanner, Jr Queen Janessa Gardener, Queen 2nd Attendant Shyann Andrus, Queen Taylor Hyma
Effect of chestnut tannin on fermentation quality and rumen degradability of lucerne (Medicago Sativa L.) sillage
No full textLa première mise en couple en Suisse : choix du type d'union et devenir de la cohabitation hors mariage
No full textCharton Laurence, Wanner Philippe.- First couple formation in Switzerland: choice of type of union and outcome of extra-marital cohabitation Changes in family formation behaviour are responsible for the coexistence of two forms of union in the developed countries: the fairly "flexible" extra-marital cohabitation, and the more formal or official form, marriage. Cohabitation is on the increase in Switzerland, currently accounting for nearly 9 in 10 newly-formed couples, but marriage is still considered the necessary condition for starting a family and the level of extra-marital births remains among the lowest in Europe. In this context, it is highly instructive to study the factors that influence decisions about the form of the first union and the duration of non-marital cohabitation. The main finding of this article based on a survey of the family is that decisions about type of union are strongly influenced by religious observance, the fact of being pregnant, and economic circumstances. While educational attainment appears not to modify the form of union chosen at the time of couple formation, it is associated with the durations of premarital cohabitation.Charton Laurence, Wanner Philippe.- La première mise en couple en Suisse : choix du type d'union et devenir de la cohabitation hors mariage Les modifications des comportements familiaux ont provoqué, dans les pays occidentaux, la coexistence de deux formes d'union, l'une plutôt « souple », la cohabitation hors mariage, l'autre plus solennelle ou officielle, le mariage. En Suisse, alors que la cohabitation augmente pour concerner aujourd'hui près de 9 couples qui se constituent sur 10, le mariage reste la condition nécessaire à la naissance de l'enfant, les naissances hors mariage étant toujours à un niveau parmi les plus faibles d'Europe. Dans ce contexte, l'étude des facteurs susceptibles d'influencer le choix de la forme de la première union, ainsi que la durée de la première cohabitation non maritale, sont riches en enseignements. Reposant sur une enquête sur la famille, cet article montre notamment le rôle très marqué de la pratique religieuse, d'une éventuelle grossesse en cours et de la situation économique sur le choix du type d'union. Alors qu'il ne paraît pas modifier la forme d'union choisie au moment de la mise en couple, le niveau de formation atteint a une influence sur la durée passée en cohabitation prémaritale.Charton Laurence, Wanner Philippe.- La primera union en pareja en Suiza: tipo de union y evolución de la cohabitación fuera del matrimonio En los países occidentales, las transformaciones de los comportamientos familiares han dado como resultado la coexistencia de dos formas de union: una relativamente flexible, la cohabitación fuera del matrimonio, y otra más oficial, el matrimonio. En Suiza, 9 de cada 10 nuevas parejas optan por la cohabitación, pero el matrimonio sigue siendo una condición necesana para el naciimento de un hijo; los nacimientos fuera del matrimonio se mantienen en uno de los nivelés más bajos de Europa. El estudio de los factures que influyen en la elec- ción del tipo de union y en la duración de la primera cohabitación no marital aporta înforma- ción interesante. En base a una encuesta sobre la familia, este articulo muestra, por ejemplo, que la práctica religiosa, la situación económica y un embarazo en curso juegan un papel importante en el tipo de union. El nivel de formación no parece influir en el tipo de union esco- gido pero si en la duración de la cohabitación prematrimonial.Charton L., Wanner P. La première mise en couple en Suisse : choix du type d'union et devenir de la cohabitation hors mariage. In: Population, 56ᵉ année, n°4, 2001. pp. 539-567
Ultrastructural analysis of chromatin in meiosis I plus II of rye (Secale cereale L.)
No full textScanning electron microscopy (SEM) proves to be an appropriate technique for imaging chromatin organization in meiosis I and II of rye (Secale cereale) down to a resolution of a few nanometers. It could be shown for the first time that organization of basic structural elements (coiled and parallel fibers, chromomeres) changes dramatically during the progression to metaphase I and II. Controlled loosening with proteinase K (after fixation with glutaraldehyde) provides an enhanced insight into chromosome architecture even of highly condensed stages of meiosis. By selective staining with platinum blue, DNA content and distribution can be visualized within compact chromosomes as well as in a complex arrangement of fibers. Chromatin interconnecting threads, which are typically observed in prophase I between homologous and non-homologous chromosomes, stain clearly for DNA. In zygotene transversion of chromatid strands to their homologous counterparts becomes evident. In pachytene segments of synapsed and non-synapsed homologs alternate. At synapsed regions pairing is so intimate that homologous chromosomes form one filament of structural entity. Chiasmata are characterized by chromatid strands which traverse from one homolog to its counterpart. Bivalents are characteristically fused at their telomeric regions. In metaphase I and II there is no structural evidence for primary and secondary constrictions. Copyright (C) 2003 S. Karger AG, Basel
Generation of Multilingual Personalized Environmental Bulletins from an OWL-based Ontology
No full textIn this paper, we tackle the problem of generation of user-oriented multilingual environmental information from ontologies in the context of a personalized environmental decision support service. We present a unified multiple layer ontology framework modeled in OWL that consists of three ontology layers: the domain ontology, the domain communication ontology, and the communication ontology. The domain ontology contains factual application-neutral concept configurations and relations. The domain communication ontology models data aggregation, qualitative interpretation of numerical data, user tailored warnings and recommendations triggered by an environmental condition given in a specific context, etc., while the communication ontology specifies knowledge needed for the tasks involved in the generation process, and is populated using a pipeline of SPARQL queries. We show how a large scale instantiation of this framework in the environmental domain serves multilingual NLG
Benchmarking the simulation of Cr isotope fractionation
No full textA benchmark problem set consisting of four problem levels was developed for the simulation of Cr isotope fractionation in 1D and 2D domains. The benchmark is based on a recent field study where Cr(VI) reduction and accompanying Cr isotope fractionation occurs abiotically by an aqueous reaction with dissolved Fe 2+ (Wanner et al., 2012., Appl. Geochem., 27, 644–662). The problem set includes simulation of the major processes affecting the Cr isotopic composition such as the dissolution of various Cr(VI) bearing minerals, fractionation during abiotic aqueous Cr(VI) reduction, and non-fractionating precipitation of Cr(III) as sparingly soluble Cr-hydroxide.
Accuracy of the presented solutions was ensured by running the problems with four well-established reactive transport modeling codes: TOUGHREACT, MIN3P, CRUNCHFLOW, and FLOTRAN. Results were also compared with an analytical Rayleigh-type fractionation model. An additional constraint on the correctness of the results was obtained by comparing output from the problem levels simulating Cr isotope fractionation with the corresponding ones only simulating bulk concentrations. For all problem levels, model to model comparisons showed excellent agreement, suggesting that for the tested geochemical processes any code is capable of accurately simulating the fate of individual Cr isotopes
Chromosome condensation in mitosis and meiosis of rye (Secale cereale L.)
No full textStructural investigation and morphometry of meiotic chromosomes by scanning electron microscopy (in comparison to light microscopy) of all stages of condensation of meiosis I + II show remarkable differences during chromosome condensation in mitosis and meiosis I of rye (Secale cereale) with respect to initiation, mode and degree of condensation. Mitotic chromosomes condense in a linear fashion, shorten in length and increase moderately in diameter. In contrast, in meiosis I, condensation of chromosomes in length and diameter is a sigmoidal process with a retardation in zygotene and pachytene and an acceleration from diplotene to diakinesis. The basic structural components of mitotic chromosomes of rye are ``parallel fibers{''} and ``chromomeres{''} which become highly compacted in metaphase. Although chromosome architecture in early prophase of meiosis seems similar to mitosis in principle, there is no equivalent stage during transition to metaphase I when chromosomes condense to a much higher degree and show a characteristic ``smooth{''} surface. No indication was found for helical winding of chromosomes either in mitosis or in meiosis. Based on measurements, we propose a mechanism for chromosome dynamics in mitosis and meiosis, which involves three individual processes: (i) aggregation of chromatin subdomains into a chromosome filament, (ii) condensation in length, which involves a progressive increase in diameter and (iii) separation of chromatids. Copyright (C) 2003 S. Karger AG, Basel
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