14 resultados para Anderson, Margaret C. (1890-....) -- Portraits
em Repositório da Produção Científica e Intelectual da Unicamp
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Super elastic nitinol (NiTi) wires were exploited as highly robust supports for three distinct crosslinked polymeric ionic liquid (PIL)-based coatings in solid-phase microextraction (SPME). The oxidation of NiTi wires in a boiling (30%w/w) H2O2 solution and subsequent derivatization in vinyltrimethoxysilane (VTMS) allowed for vinyl moieties to be appended to the surface of the support. UV-initiated on-fiber copolymerization of the vinyl-substituted NiTi support with monocationic ionic liquid (IL) monomers and dicationic IL crosslinkers produced a crosslinked PIL-based network that was covalently attached to the NiTi wire. This alteration alleviated receding of the coating from the support, which was observed for an analogous crosslinked PIL applied on unmodified NiTi wires. A series of demanding extraction conditions, including extreme pH, pre-exposure to pure organic solvents, and high temperatures, were applied to investigate the versatility and robustness of the fibers. Acceptable precision of the model analytes was obtained for all fibers under these conditions. Method validation by examining the relative recovery of a homologous group of phthalate esters (PAEs) was performed in drip-brewed coffee (maintained at 60 °C) by direct immersion SPME. Acceptable recoveries were obtained for most PAEs in the part-per-billion level, even in this exceedingly harsh and complex matrix.
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Purpose After a successful pyeloplasty at 3 to 6 months, the question remains whether children need a long follow-up. Methods The medical charts of patients with long-term follow-up (> 5 years), who underwent dismembered pyeloplasty for uretero-pelvic junction obstruction (UPJO) from May 1998 to May 2007, excluding those with bilateral UPJO, solitary kidney, associated vesicoureteral reflux or other abnormalities, and inconclusive renogram due to poor renal function, were retrospectively reviewed. Ultrasonography, differential renal function (DRF, DMSA), and renal drainage on diuretic renography (diethylene-triamine-pentaacetate technetium-99 or DTPA-Tc99) were performed at 3 and 6 months every year. Results Complete data were available for 28 consecutive patients (28 renal unities) with 2 months to 12 years (mean age, 2.4 years) at surgery, of whom 21 (75%) were boys, 17 diagnosed prenatally (61%) and 18 unities (64.3%) were left, with median follow-up of 10.7 years. Images were graded according to the Society for Fetal Urology grading system: Grade III in 11 (49%) and grade IV in 17 (61%). All cases presented > 10% DRF (DMSA) and obstructed DTPA-Tc99. The T1/2 (the half-time of drainage) less than 20 minutes at 3 months was found in 21 cases (75%) and less than 25 minutes in 7 cases (25%). Renal function and patency were maintained during follow-up for all units with 8% maximum fluctuation of DRF. One index case (3.6%) of renal function deterioration presented DRF fluctuation > 8% at 3 months (from 23 to 32%) and progressive hydronephrosis and indeterminate DTPA at 6 months. Conclusions Satisfactory diuretic renogram at 3 to 6 months after pyeloplasty with maintained renal function and stable hydronephrosis suggests no need for further follow-up and indicates no functional loss with time. More than 8% DRF fluctuation might be a significant cutoff for further intervention aiming nephron preservation.
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Mutations in the FGFR3 gene cause the phenotypic spectrum of FGFR3 chondrodysplasias ranging from lethal forms to the milder phenotype seen in hypochondroplasia (Hch). The p.N540K mutation in the FGFR3 gene occurs in ∼70% of individuals with Hch, and nearly 30% of individuals with the Hch phenotype have no mutations in the FGFR3, which suggests genetic heterogeneity. The identification of a severe case of Hch associated with the typical mutation c.1620C > A and the occurrence of a c.1150T > C change that resulted in a p.F384L in exon 10, together with the suspicion that this second change could be a modulator of the phenotype, prompted us to investigate this hypothesis in a cohort of patients. An analysis of 48 patients with FGFR3 chondrodysplasia phenotypes and 330 healthy (control) individuals revealed no significant difference in the frequency of the C allele at the c.1150 position (p = 0.34). One patient carrying the combination `pathogenic mutation plus the allelic variant c.1150T > C' had a typical achondroplasia (Ach) phenotype. In addition, three other patients with atypical phenotypes showed no association with the allelic variant. Together, these results do not support the hypothesis of a modulatory role for the c.1150T > C change in the FGFR3 gene.
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With a huge amount of printed documents nowadays, identifying their source is useful for criminal investigations and also to authenticate digital copies of a document. In this paper, we propose novel techniques for laser printer attribution. Our solutions do not need very high resolution scanning of the investigated document and explore the multidirectional, multiscale and low-level gradient texture patterns yielded by printing devices. The main contributions of this work are: (1) the description of printed areas using multidirectional and multiscale co-occurring texture patterns; (2) description of texture on low-level gradient areas by a convolution texture gradient filter that emphasizes textures in specific transition areas and (3) the analysis of printer patterns in segments of interest, which we call frames, instead of whole documents or only printed letters. We show by experiments in a well documented dataset that the proposed methods outperform techniques described in the literature and present near-perfect classification accuracy being very promising for deployment in real-world forensic investigations.
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We perform variational studies of the interaction-localization problem to describe the interaction-induced renormalizations of the effective (screened) random potential seen by quasiparticles. Here we present results of careful finite-size scaling studies for the conductance of disordered Hubbard chains at half-filling and zero temperature. While our results indicate that quasiparticle wave functions remain exponentially localized even in the presence of moderate to strong repulsive interactions, we show that interactions produce a strong decrease of the characteristic conductance scale g^{*} signaling the crossover to strong localization. This effect, which cannot be captured by a simple renormalization of the disorder strength, instead reflects a peculiar non-Gaussian form of the spatial correlations of the screened disordered potential, a hitherto neglected mechanism to dramatically reduce the impact of Anderson localization (interference) effects.
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The p23 protein is a chaperone widely involved in protein homeostasis, well known as an Hsp90 co-chaperone since it also controls the Hsp90 chaperone cycle. Human p23 includes a β-sheet domain, responsible for interacting with Hsp90; and a charged C-terminal region whose function is not clear, but seems to be natively unfolded. p23 can undergo caspase-dependent proteolytic cleavage to form p19 (p231-142), which is involved in apoptosis, while p23 has anti-apoptotic activity. To better elucidate the function of the human p23 C-terminal region, we studied comparatively the full-length human p23 and three C-terminal truncation mutants: p23₁₋₁₁₇; p23₁₋₁₃₁ and p23₁₋₁₄₂. Our data indicate that p23 and p19 have distinct characteristics, whereas the other two truncations behave similarly, with some differences to p23 and p19. We found that part of the C-terminal region can fold in an α-helix conformation and slightly contributes to p23 thermal-stability, suggesting that the C-terminal interacts with the β-sheet domain. As a whole, our results suggest that the C-terminal region of p23 is critical for its structure-function relationship. A mechanism where the human p23 C-terminal region behaves as an activation/inhibition module for different p23 activities is proposed.
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In this work, all publicly-accessible published findings on Alicyclobacillus acidoterrestris heat resistance in fruit beverages as affected by temperature and pH were compiled. Then, study characteristics (protocols, fruit and variety, °Brix, pH, temperature, heating medium, culture medium, inactivation method, strains, etc.) were extracted from the primary studies, and some of them incorporated to a meta-analysis mixed-effects linear model based on the basic Bigelow equation describing the heat resistance parameters of this bacterium. The model estimated mean D* values (time needed for one log reduction at a temperature of 95 °C and a pH of 3.5) of Alicyclobacillus in beverages of different fruits, two different concentration types, with and without bacteriocins, and with and without clarification. The zT (temperature change needed to cause one log reduction in D-values) estimated by the meta-analysis model were compared to those ('observed' zT values) reported in the primary studies, and in all cases they were within the confidence intervals of the model. The model was capable of predicting the heat resistance parameters of Alicyclobacillus in fruit beverages beyond the types available in the meta-analytical data. It is expected that the compilation of the thermal resistance of Alicyclobacillus in fruit beverages, carried out in this study, will be of utility to food quality managers in the determination or validation of the lethality of their current heat treatment processes.
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Vitamin C stability and concentration was evaluated in isotonic beverages and B group vitamins (B1, B2, B3, B5 and B6) in power beverages. The amount of vitamins was found to be above of that declared on the labels, even after the shelf life had been exceeded. A small decrease in the amount of B group vitamins was observed during the shelf life of the products. In the case of vitamin C this decrease was slightly higher. The present research shows the need of increased quality control and inspection.
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The aggregation behavior of the non-ionic surfactant Renex-100 in aqueous solutions and mesophases was evaluated by SAXS in a wide range of concentrations, between 20 and 30 °C. Complementary, water interactions were defined by DSC curves around 0°C. SAXS showed that the system undergoes the following phase transitions, from diluted to concentrated aqueous solutions: 1) isotropic solution of Renex aggregates; 2) hexagonal mesophase; 3) lamellar mesophase; and 4) isotropic solution. DSC analysis indicated the presence of interfacial water above 70wt%, which agreed with the segregation of free water to form the structural mesophases observed by SAXS bellow this concentration.
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Edibles films are an alternative to synthetic materials used for packing food products. Barbados cherry is rich in vitamin C and carotenoids. The aim of this study was to characterize and develop films by casting from cassava starch, lyophilized Barbados cherry pulp and glycerol. The films were characterized with respect to thickness, water vapor permeability (WVP), water solubility, vitamin C, carotene and mechanical properties. The interaction of pulp and glycerol reduced film thickness. An increase in pulp concentration up to 60% increased WVP but beyond this concentration reduced both WVP and solubility leading to an increased level of vitamin C and β carotene in the films.
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Purpose: To analyze the efficacy and safety of intraope-rative mitomycin C (MMC) in combined procedures (extra-capsular cataract extraction + trabeculectomy). Methods: Twenty-four patients were randomized to either MMC (0.5 mg/ml) (n = 14) or saline solution (n = 10) for 3 minutes during the combined procedure. Results: Twelve months after surgery, mean IOP in the MMC group (13.2 ± 2.9 mmHg) was significantly lower than in the control group (16.3 ± 3.9 mmHg) (p = 0.02). The mean number of medications used during the 12-month follow-up in the control group (1.33 ± 0.5) was significantly higher than in the MMC-treated group (0.5 ± 0.5) (p = 0.005). Life table analysis showed a significantly higher probability of IOP control in the MMC group than in the control group (p < 0.01). Conclusions: Intraoperative MMC is safe and effective in pro-moting a better IOP control and reducing the need for postoperative antiglaucoma medications. We suggest intraope-rative MMC to be routinely employed in combined procedures.
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The purpose of this paper is to report a case of central retinal vein thrombosis associated with isolated heterozygous protein C deficiency. Acute occlusion of the central retinal vein presents as one of the most dramatic pictures in ophthalmology. It is often a result of both local and systemic causes. A rare systemic cause is heterozygous protein C deficiency, and it usually occurs in combination with other thrombophilic conditions. This case highlights that isolated heterozygous protein C deficiency may be the cause of central retinal vein thrombosis and underscores the importance of its screening in young patients with this ophthalmologic disease.
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Universidade Estadual de Campinas. Faculdade de Educação Física
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Universidade Estadual de Campinas . Faculdade de Educação Física