993 resultados para ti-modified columbite route
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Rabies is a neurotropic disease that is often lethal. The early diagnosis of rabies infection is important and requires methods that allow for the isolation of the virus from animals and humans. The present study compared a modified shell vial (MSV) procedure using 24-well tissue culture plates with the mouse inoculation test (MIT), which is considered the gold standard for rabies virus isolation. Thirty brain samples (25 positive and 5 negative by the fluorescent antibody test) obtained from different animal species at the National Institute of Hygiene Rafael Rangel in Caracas, Venezuela, were studied by the MIT and MSV assays. Nine samples (36%) were positive at 24 h, 10 (40%) were positive at 48 h and six (24%) were positive at 72 h by the MSV assay. With the MIT assay, 76% were positive at six days post inoculation and 12% were positive at 12 and 18 days post inoculation. One sample that was negative according to the MSV assay was positive with MIT on the 12th day. The MSV procedure exhibited a sensitivity of 96.2%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value 80%. This procedure allowed for rapid rabies virus detection. MIT can be employed as an alternative method in laboratories without tissue culture facilities.
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Nowadays, there are several services and applications that allow users to locate and move to different tourist areas using a mobile device. These systems can be used either by internet or downloading an application in concrete places like a visitors centre. Although such applications are able to facilitate the location and the search for points of interest, in most cases, these services and applications do not meet the needs of each user. This paper aims to provide a solution by studying the main projects, services and applications, their routing algorithms and their treatment of the real geographical data in Android mobile devices, focusing on the data acquisition and treatment to improve the routing searches in off-line environments.
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The expression on a significant number of thymocytes of idiotypic structures (Ti) restricted to HPB-ALL or Jurkat cells is demonstrated. As many as 2-4% of thymocytes were stained with anti-Ti HPB-ALL or anti-Ti Jurkat monoclonal antibodies, when analyzed by flow microfluorometry. Immunohistochemical localization studies performed on frozen thymus specimens of either fetal or pediatric origin indicated a scattered distribution of Ti-positive cells in both the cortex and the medulla. From lysates of 125I-labeled pediatric thymocytes, anti-Ti HPB-ALL and anti-Ti Jurkat monoclonal antibodies precipitated disulfide-linked heterodimers comparable to those precipitated from 125I-labeled HPB-ALL or Jurkat cells as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis.
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Las tecnologías de información (TI) constituyen en la actualidad una herramienta fundamental para el logro de ventajas competitivas en un contexto sumamente cambiante. Resulta relevante conocer el impacto de su utilización sobre el desempeño de las organizaciones, en particular en sectores como el bancario, que realizan un uso intensivo de información. En el presente trabajo se desarrolla un modelo que posibilita evaluar el impacto de las inversiones en TI sobre la eficiencia de las entidades bancarias. Se utilizó la técnica Data Envelopment Analysis (DEA) como herramienta de medición de la eficiencia de acuerdo al modelo elaborado sobre la información obtenida de los estados contables de entidades bancarias de la República Argentina. Los resultados obtenidos demostraron que los bancos alcanzaron un buen nivel de eficiencia global. Se encontró que los más eficientes son las sucursales de entidades financieras del exterior y los bancos locales de capital extranjero.
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Em resposta às crescentes mudanças e pressões da concorrência, número cada vez maior de empresas tem estabelecido alianças como forma de complementar seus recursos e assegurar suas vantagens competitivas. Embora essas alianças sejam uma boa opção estratégica para as empresas, existem evidências de grande taxa de fracasso. Muitos estudos têm analisado os fatores de sucesso das parcerias, mas poucos têm dado ênfase às dificuldades e à prevenção de riscos. O objetivo neste artigo consiste em apresentar os resultados de uma pesquisa em que se buscou identificar os fatores de risco que dificultam as alianças no caso de projetos de Tecnologia da Informação (TI). Trata-se de uma pesquisa exploratória, focada em cinco projetos estratégicos de TI do Banco Central do Brasil, desenvolvidos em parceria com outras instituições públicas e privadas, a maioria delas nacionais e uma estrangeira. Apesar de os projetos terem tido sucesso, foi possível identificar como principais fatores de risco: falta de planejamento da aliança, falta de negociação entre parceiros, falta de comprometimento dos parceiros e falta de apoio institucional. A pesquisa trouxe lições relevantes para o gerenciamento de projetos que podem beneficiar outras alianças em projetos de TI.
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Most models on introgression from genetically modified (GM) plants have focused on small spatial scales, modelling gene flow from a field containing GM plants into a single adjacent population of a wild relative. Here, we present a model to study the effect of introgression from multiple plantations into the whole metapopulation of the wild relative. The most important result of the model is that even very low levels of introgression and selection can lead to a high probability that the transgene goes to fixation in the metapopulation. Furthermore, the overall frequency of the transgene in the metapopulation, after a certain number of generations of introgression, depends on the population dynamics. If there is a high rate of migration or a high rate of population turnover, the overall transgene frequency is much higher than with lower rates. However, under an island model of population structure, this increased frequency has only a very small effect on the probability of fixation of the transgene. Considering these results, studies on the potential ecological risks of introgression from GM plants should look not only at the rate of introgression and selection acting on the transgene, but also at the metapopulation dynamics of the wild relative.
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The present work reports on the preparation of thermoplastic starch (TPS) modified in situ with a diisocyanate derivative. Evidence of the condensation reaction between the hydroxyl groups of starch and glycerol with the isocyanate function (NCO) was confirmed by FTIR analysis. The evolution of the properties of the ensuing TPS, in term of mechanical properties, microstructure, and water sensitivity, was investigated using tensile mechanical, dynamic mechanical thermal analysis (DMTA), X-ray diffraction (XRD), and water uptake. The results showed that the addition of isocyanate did not affect the crystallinity of the TPS and slightly reduced the water uptake of the material. The evolution of the mechanical properties with ageing became less pronounced by the addition of the isocyanate as their amount exceeded 4 to 6wt%.
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Purpose: Crosslinking of corneal collagen with riboflavin and ultraviolet-A irradiation (CXL) induces crosslinks within and between collagen fibers. CXL increases corneal biomechanical and biochemical stability and is currently used clinically to treat keratectasia. CXL also significantly reduces the stromal swelling capacity. We investigated whether a modified CXL treatment protocol would be beneficial in early Fuchs' dystrophy with various degrees of corneal edema and diurnal variations in visual acuity. Methods: CXL was performed as published previously with the following modification: in cases where the stroma was thicker than 450 µm after abrasion and 30 minutes of instillation of isoosmolar riboflavin solution, glycerol 70% solution was applied every 5 seconds for two minutes, and central corneal thickness (CCT) was measured using ultrasound pachymetry. Glycerol 70% solution was administered repeatedly until the target corneal thickness of 370-430 µm was reached. During irradiation, CCT was monitored by ultrasound pachymetry every five minutes and glycerol 70% solution was applied, if necessary. Results: Three eyes in two patients were treated using the modified CXL protocol. Representative case: a 50-year-old woman with Fuchs' dystrophy and a history of 3 years of diurnal visual fluctuations was referred to us in March 2008. Preoperative best spectacle-corrected visual acuity (BSCVA) was 20/50. We performed modified CXL in the left eye. At one month after CXL, Scheimpflug analysis of CCT showed a reduction of more than 100 µm, and the Corneal Thickness Spatial Profile (CTSP) and Percentage of Increase in Thickness (PIT) showed a regularization of the "flattening" typical for Fuchs' dystrophy. Accordingly, diurnal analysis of corneal thickness showed a distinct postoperative reduction in CCT at all time points measured. At one month after CXL, the patient reported a reduction of diurnal visual fluctuations and we measured an increase in BSCVA to 20/32. The patient showed stable topographical and visual acuity at the three months follow-up. Conclusions: We saw a distinct reduction in CCT, an improvement of the corneal thickness spatial profile (CTSP) and an increase in BSCVA at one month after treatment, which remained stable at the three months follow-up. Patients with early Fuchs' dystrophy and disturbing diurnal visual fluctuations represent a novel application for CXL. Although CXL may not prevent the outcome of the dystrophy, it may increase the patients' visual comfort until keratoplasty becomes necessary.
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Spatial regulation of tyrosine phosphorylation is important for many aspects of cell biology. However, phosphotyrosine accounts for less than 1% of all phosphorylated substrates, and it is typically a very transient event in vivo. These factors complicate the identification of key tyrosine kinase substrates, especially in the context of their extraordinary spatial organization. Here, we describe an approach to identify tyrosine kinase substrates based on their subcellular distribution from within cells. This method uses an unnatural amino acid-modified Src homology 2 (SH2) domain that is expressed within cells and can covalently trap phosphotyrosine proteins on exposure to light. This SH2 domain-based photoprobe was targeted to cellular structures, such as the actin cytoskeleton, mitochondria, and cellular membranes, to capture tyrosine kinase substrates unique to each cellular region. We demonstrate that RhoA, one of the proteins associated with actin, can be phosphorylated on two tyrosine residues within the switch regions, suggesting that phosphorylation of these residues might modulate RhoA signaling to the actin cytoskeleton. We conclude that expression of SH2 domains within cellular compartments that are capable of covalent phototrapping can reveal the spatial organization of tyrosine kinase substrates that are likely to be important for the regulation of subcellular structures.
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Référence bibliographique : Rol, 57112
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Référence bibliographique : Rol, 57266
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Référence bibliographique : Rol, 57264