769 resultados para Normalization


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A method for quantitative mineralogical analysis by ATR-FTIR has been developed. The method relies on the use of the main band of calcite as a reference for the normalization of the IR spectrum of a mineral sample. In this way, the molar absorptivity coefficient in the Lambert–Beer law and the components of a mixture in mole percentage can be calculated. The GAMS equation modeling environment and the NLP solver CONOPT (©ARKI Consulting and Development) were used to correlate the experimental data in the samples considered. Mixtures of different minerals and gypsum were used in order to measure the minimum band intensity that must be considered for calculations and the detection limit. Accordingly, bands of intensity lower than 0.01 were discarded. The detection limit for gypsum was about 7% (mol/total mole). Good agreement was obtained when this FTIR method was applied to ceramic tiles previously analyzed by X-ray diffraction (XRD) or mineral mixtures prepared in the lab.

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«Viatjant i llegint: promoció de la lectura i vertebració del país» és un projecte de promoció de la lectura i del patrimoni cultural engegat per la Coordinadora pel Valencià de l'Alcoià-Comtat (Escola Valenciana). Des de l'any 2007 s'han posat en marxa una sèrie de rutes literàries amb un destinatari doble: el món educatiu, per la vessant didàctica i d'animació a la lectura; i el públic en general, per la dimensió de promoció turística i de redreçament de la identitat. L'article provarà de justificar el recurs de les rutes literàries com una eina útil per a l'animació a la lectura i la normalització del valencià. Explicarà en què han consistit tres d'aquestes propostes i farà una aplicació didàctica de cadascuna, en funció del nivell educatiu en què poden ser treballades, des d'educació primària a secundària i batxillerat.

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Tese de doutoramento, Farmácia (Biologia Celular e Molecular), Universidade de Lisboa, Faculdade de Farmácia, 2016

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Dans cette thèse, l’impact du polymorphisme rs3846662 sur l’épissage alternatif de la 3-hydroxy-3-méthylglutaryl coenzyme A réductase (HMGCR) a été investigué in vivo, chez des patients atteints d’hypercholestérolémie familiale (HF) ou de maladie d’Alzheimer (MA). Le premier manuscrit adresse la problématique de la normalisation de la quantification relative des ARNm par PCR quantitative. Les découvertes présentées dans ce manuscrit nous ont permis de déterminer avec un haut niveau de confiance les gènes de référence à utiliser pour la quantification relative des niveaux d’ARNm de l’HMGCR dans des échantillons de sang (troisième manuscrit) et de tissus cérébraux post-mortem (quatrième manuscrit). Dans le deuxième manuscrit, nous démontrons grâce à l’emploi de trois cohortes de patients distinctes, soit la population canadienne française du Québec et les deux populations nord américaines « Alzheimer’s Disease Cooperative Study (ADCS) » et « Alzheimer’s Disease Neuroimaging Initiative (ADNI) », que le génotype AA au locus rs3846662 confère à ces porteurs une protection considérable contre la MA. Les femmes porteuses de ce génotype voient leur risque de MA diminuer de près de 50% et l’âge d’apparition de leurs premiers symptômes retarder de 3.6 ans. Les porteurs de l’allèle à risque APOE4 voient pour leur part leurs niveaux de plaques séniles et dégénérescences neurofibrillaires diminuer significativement en présence du génotype AA. Enfin, les individus atteints de déficit cognitif léger et porteurs à la fois de l’allèle APOE4 et du génotype protecteur AA voient leur risque de convertir vers la MA chuter de 76 à 27%. Dans le troisième manuscrit, nous constatons que les individus atteints d’HF et porteurs du génotype AA ont, contrairement au modèle établi chez les gens normaux, des niveaux plus élevés de cholestérol total et de LDL-C avant traitement comparativement aux porteurs de l’allèle G. Le fait que cette association n’est observée que chez les non porteurs de l’APOE4 et que les femmes porteuses du génotype AA présentent à la fois une augmentation des niveaux d’ARNm totaux et une résistance aux traitements par statines, nous indique que ce génotype influencerait non seulement l’épissage alternatif, mais également la transcription de l’HMGCR. Comme une revue exhaustive de la littérature ne révèle aucune étude abondant dans ce sens, nos résultats suggèrent l’existence de joueurs encore inconnus qui viennent influencer la relation entre le génotype AA, l’épissage alternatif et les niveaux d’ARNm de l’HMGCR. Dans le quatrième manuscrit, l’absence d’associations entre le génotype AA et les niveaux d’ARNm Δ13 ou de protéines HMGCR nous suggère fortement que ce polymorphisme est non fonctionnel dans le SNC affecté par la MA. Une étude approfondie de la littérature nous a permis d’étayer cette hypothèse puisque les niveaux de HNRNPA1, la ribonucléoprotéine influencée par l’allèle au locus rs3846662, sont considérablement réduits dans la MA et le vieillissement. Il est donc proposé que les effets protecteurs contre la MA associés au génotype AA soient le résultat d’une action indirecte sur le processus physiopathologique.

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El presente trabajo se propone abordar los sucesos que marcaron la dinámica institucional y política de la Universidad de La Plata en los meses que van entre septiembre de 1955 y mayo de 1956, con énfasis en un actor en particular: el movimiento estudiantil. Mediante el trabajo con fuentes documentales escritas de diversa índole vamos a reconstruir los primeros meses de la UNLP posperonista, atendiendo a tres aspectos del proceso abierto: en primer lugar, el proceso de reconstrucción y desperonización de las estructuras universitarias y del cuerpo docente y administrativo. Segundo, vamos a preguntarnos cuál fue el rol del movimiento estudiantil: qué acciones llevó a cabo, cuáles eran sus diferencias internas y sus principales debates. Como es conocido, el proceso de normalización universitaria atravesó un momento disruptivo comenzando 1956: la sanción del Decreto-Ley 6.403, y en particular su artículo n°28, va a provocar masivas movilizaciones (tanto a su favor como en contra), numerosas tomas e incluso fuertes incidentes en las calles platenses. Las últimas líneas del trabajo estarán dedicadas a este tercer aspecto del período señalado.

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Application of the 230Th normalization method to estimate sediment burial fluxes in six cores from the eastern equatorial Pacific (EEP) reveals that bulk sediment and organic carbon fluxes display a coherent regional pattern during the Holocene that is consistent with modern oceanographic conditions, in contrast with estimates of bulk mass accumulation rates (MARs) derived from core chronologies. Two nearby sites (less than 10 km apart), which have different MARs, show nearly identical 230Th-normalized bulk fluxes. Focusing factors derived from the 230Th data at the foot of the Carnegie Ridge in the Panama Basin are >2 in the Holocene, implying that lateral sediment addition is significant in this part of the basin. New geochemical data and existing literature provide evidence for a hydrothermal source of sediment in the southern part of the Panama Basin and for downslope transport from the top of the Carnegie Ridge. The compilation of core records suggests that sediment focusing is spatially and temporally variable in the EEP. During oxygen isotope stage 2 (OIS 2, from 13-27 ka BP), focusing appears even higher compared to the Holocene at most sites, similar to earlier findings in the eastern and central equatorial Pacific. The magnitude of the glacial increase in focusing factors, however, is strongly dependent on the accuracy of age models. We offer two possible explanations for the increase in glacial focusing compared to the Holocene. The first one is that the apparent increase in lateral sediment redistribution is partly or even largely an artifact of insufficient age control in the EEP, while the second explanation, which assumes that the observed increase is real, involves enhanced deep sea tidal current flow during periods of low sea level stand.

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We present biogenic opal flux records from two deep-sea sites in the Scotia Sea (MD07-3133 and MD07-3134) at decadal-scale resolution, covering the last glacial cycle. Besides conventional and time-consuming biogenic opal measuring methods, we introduce new biogenic opal estimation methods derived from sediment colour b*, wet bulk density, Si/Ti-count ratio, and Fourier transform infrared spectroscopy (FTIRS). All methods capture the biogenic opal amplitude, however, FTIRS - a novel method for marine sediment - yields the most reliable results. 230Th normalization data show strong differences in sediment focusing with intensified sediment focusing during glacial times. At MD07-3134 230Th normalized biogenic opal fluxes vary between 0.2 and 2.5 g/cm2/kyr. Our biogenic opal flux records indicate bioproductivity changes in the Southern Ocean, strongly influenced by sea ice distribution and also summer sea surface temperature changes. South of the Antarctic Polar Front, lowest bioproductivity occurred during the Last Glacial Maximum when upwelling of mid-depth water was reduced and sea ice cover intensified. Around 17 ka, bioproductivity increased abruptly, corresponding to rising atmospheric CO2 contents and decreasing seasonal sea ice coverage.

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Thesis (Master's)--University of Washington, 2016-06

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Thesis (Ph.D.)--University of Washington, 2016-06

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Background: Observation of the occurrence of protective muscle activity is advocated in assessment of the peripheral nervous system by means of neural provocation tests. However, no studies have yet demonstrated abnormal force generation in a patient population. Objectives: To analyze whether aberrations in shoulder girdle-elevation force during neural tissue provocation testing for the median nerve (NTPTI) can be demonstrated, and whether possible aberrations can be normalized following cervical mobilization. Study Design: A single-blind randomized comparative controlled study. Setting: Laboratory setting annex in a manual therapy teaching practice. Participants: Twenty patients with unilateral or bilateral neurogenic cervicobrachial pain. Methods: During the NTPTI, we used a load cell and electrogoniometer to record continuously the shoulder-girdle elevation force in relation to the available range of elbow extension. Following randomization, we analyzed the immediate treatment effects of a cervical contralateral lateral glide mobilization technique (experimental group) and therapeutic ultrasound (control group). Results: On the involved side, the shoulder-girdle elevation force occur-red earlier, and the amount of force at the end of the test was substantially, though not significantly, greater than that on the uninvolved side at the corresponding range of motion. Together with a significant reduction in pain perception after cervical mobilization, a clear tendency toward normalization of the force curve could be observed, namely, a significant decrease in force generation and a delayed onset. The control group demonstrated no differences. Conclusions: Aberrations in force generation during neural, provocation testing are present in patients with neurogenic pain and can be normalized with appropriate treatment modalities.

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We report the construction of the mouse full-length cDNA encyclopedia, the most extensive view of a complex transcriptome, on the basis of preparing and sequencing 246 libraries. Before cloning, cDNAs were enriched in full-length by Cap-Trapper, and in most cases, aggressively subtracted/normalized. We have produced 1,442,236 successful 3'-end sequences clustered into 171,144 groups, from which 60,770 clones were fully sequenced cDNAs annotated in the FANTOM-2 annotation. We have also produced 547,149 5' end reads, which clustered into 124,258 groups. Altogether, these cDNAs were further grouped in 70,000 transcriptional units (TU), which represent the best coverage of a transcriptome so far. By monitoring the extent of normalization/subtraction, we define the tentative equivalent coverage (TEC), which was estimated to be equivalent to >12,000,000 ESTs derived from standard libraries. High coverage explains discrepancies between the very large. numbers of clusters (and TUs) of this project, which also include non-protein-coding RNAs, and the lower gene number estimation of genome annotations. Altogether, S'-end clusters identify regions that are potential promoters for 8637 known genes and S'-end clusters suggest the presence of almost 63,000 transcriptional starting points. An estimate of the frequency of polyadenylation signals suggests that at least half of the singletons in the EST set represent real mRNAs. Clones accounting for about half of the predicted TUs await further sequencing. The continued high-discovery rate suggests that the task of transcriptome discovery is not yet complete.

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Between 1993 and 2001, 106 patients with esophageal cancer were reviewed at a multidisciplinary clinic and treated with palliative intent by chemoradiation therapy. This study assesses the palliative benefit on dysphagia and documents the toxicity of this treatment. The study population comprised 72 men and 34 women with a median age of 69 years. Patients were treated with a median radiation dose of 35 Gy in 15 fractions with a concurrent single course of 5 FU-based chemotherapy. Dysphagia was measured at the beginning and completion of treatment and at monthly intervals until death, using a modified DeMeester (4-point) score. Treatment was well tolerated, with only 5% of patients failing to complete therapy. The treatment-related mortality was 6%. The median survival for the study population was 7 months. The median baseline score at presentation was 2 (difficulty with soft food). Following treatment, 49% of patients were assessed as having a dysphagia score of 0 (no dysphagia). Seventy-eight per cent had an improvement of at least one grade in their dysphagia score after treatment. Only 14% of patients showed no improvement with treatment. Fifty-one per cent maintained improved swallowing until the time of last follow-up or death. This single-institution study shows that chemoradiation therapy administered for the palliation of malignant dysphagia is well tolerated and produces a sustainable normalization in swallowing for almost half of all patients.

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Postprandial hyperglycemia is implicated as a risk factor predisposing to vascular complications. This study was designed to assess recurrent short-term increases in glucose on markers of renal fibrogenesis. Human renal cortical fibroblasts were exposed to fluctuating short-term (2 h) increases to 15 mM D-glucose, three times a day over 72 h, on a background of 5 mM D-glucose. To determine whether observed changes were due to fluctuating osmolality, identical experiments were undertaken with cells exposed to L-glucose. Parallel experiments were performed in cells exposed to 5 mM D-glucose and constant exposure to either 15 or 7.5 mM D-glucose. Fluctuating D-glucose increased extracellular matrix, as measured by proline incorporation ( P < 0.05), collagen IV ( P < 0.005), and fibronectin production ( P < 0.001), in association with increased tissue inhibitor of matrix metalloproteinase (MMP) ( P < 0.05). Sustained exposure to 15 mM D-glucose increased fibronectin ( P < 0.001), in association with increased MMP-2 ( P = 0.01) and MMP-9 activity ( P < 0.05), suggestive of a protective effect on collagen matrix accumulation. Transforming growth factor-beta(1) (TGF-beta(1)) mRNA was increased after short-term (90 min) exposure to 15 mM glucose (P < 0.05) and after 24-h exposure to 7.5 mM ? ( P < 0.05). Normalization of TGF-beta(1) secretion occurred within 48 h of constant exposure to an elevated glucose. Fluctuating L-glucose also induced TGF-beta(1) mRNA and a profibrotic profile, however, to a lesser extent than observed with exposure to fluctuating D-glucose. The results suggest that exposure to fluctuating glucose concentrations increases renal interstitial fibrosis compared with stable elevations in D-glucose. The effects are, in part, due to the inherent osmotic changes.

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Background Control of the trunk is critical for locomotor efficiency. However, investigations of trunk muscle activity and three-dimensional lumbo-pelvic kinematics during walking and running remain scarce. Methods. Gait parameters and three-dimensional lumbo-pelvic kinematics were recorded in seven subjects. Electromyography recordings of abdominal and paraspinal muscles were made using fine-wire and surface electrodes as subjects walked on a treadmill at 1 and 2 ms(-1) and ran at 2, 3, 4 and 5 ms(-1). Findings. Kinematic data indicate that the amplitude but not timing of lumbo-pelvic motion changes with locomotor speed. Conversely, a change in locomotor mode is associated with temporal but not spatial adaptation in neuromotor strategy. That is, peak transverse plane lumbo-pelvic rotation occurs at foot strike during walking but prior to foot strike during running. Despite this temporal change, there is a strong correlation between the amplitude of transverse plane lumbo-pelvic rotation and stride length during walking and running. In addition, Jumbo-pelvic motion was asymmetrical during all locomotor tasks. Trunk muscle electromyography occurred biphasically in association with foot strike. Transversus abdominis was tonically active with biphasic modulation. Consistent with the kinematic data, electromyography activity of the abdominal muscles and the superficial fibres of multifidus increased with locomotor speed, and timing of peak activity of superficial multifidus and obliquus externus abdominis was modified in association with the temporal adaptation in lumbo-pelvic motion with changes in locomotor mode. Interpretation. These data provide evidence of the association between lumbo-pelvic motion and trunk muscle activity during locomotion at different speeds and modes. (c) 2005 Elsevier Ltd. All rights reserved.