973 resultados para binary hyperplane


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The present communication reports the isolation and identification of four triterpenoid saponins from the chloroform extract of the leaves of Tocoyena brasiliensis: 3-O-beta-D-quinovopyranosyl quinovic acid, 3-O-beta-D-quinovopyranosyl cincholic acid, 3-O-beta-D-glucopyranosyl quinovic acid and the 28-O-beta-D-glucopyranosyl ester derivative of quinovic acid as binary mixtures, respectively. From the ethanol extract a flavonoid identified as ramnazin-3-O-rutinoside was obtained. The structures of these compounds were assigned by data analysis of 1D and 2D NMR spectrometry and comparison with data recorded in the literature for these compounds.

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A very simple spectrophotometric method is described for resolving binary mixture of the food colorants Sunset Yellow (INS 110) and Tartrazine Yellow (INS 102) by using the first derivative spectra with measurements at zero-crossing wavelengths. Before the spectrophotometric measurements, the dyes were sorbed onto polyurethane foam and recovered in N,N-dimethilformamide. Commercial food products (gelatine and juice powder) were analysed by using the proposed method and the HPLC technique. The results are in very good agreement and the differences between the methods is not statistically important. Therefore, the first-order derivative spectrophotometric method is accurate, precise, reliable and could be applied to the routine analysis of food samples.

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A short duration burst reminiscent of a soft gamma-ray repeater/anomalous X-ray pulsar behaviour was detected in the direction of LS I +61 303 by the Swift satellite. While the association with this well known gamma-ray binary is likely, a different origin cannot be excluded. Aims. We explore the error box of this unexpected flaring event and establish the radio, near-infrared and X-ray sources in our search for any peculiar alternative counterpart. Methods. We carried out a combined analysis of archive Very Large Array radio data of LS I +61 303 sensitive to both compact and extended emission. We also reanalysed previous near infrared observations with the 3.5 m telescope of the Centro Astronómico Hispano Alemán and X-ray observations with the Chandra satellite. Results. Our deep radio maps of the LS I +61 303 environment represent a significant advancement on previous work and 16 compact radio sources in the LS I +61 303 vicinity are detected. For some detections, we also identify near infrared and X-ray counterparts. Extended emission features in the field are also detected and confirmed. The possible connection of some of these sources with the observed flaring event is considered. Based on these data, we are unable to claim a clear association between the Swift-BAT flare and any of the sources reported here. However, this study represents the most sophisticated attempt to determine possible alternative counterparts other than LS I +61 303.

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RX J1826.2-1450/LS 5039 has been recently proposed to be a radio emitting high mass X-ray binary. In this paper, we present an analysis of its X-ray timing and spectroscopic properties using different instruments on board the RXTE satellite. The timing analysis indicates the absence of pulsed or periodic emission on time scales of 0.02-2000 s and 2-200 d, respectively. The source spectrum is well represented by a power-law model, plus a Gaussian component describing a strong iron line at 6.6 keV. Significant emission is seen up to 30 keV, and no exponential cut-off at high energy is required. We also study the radio properties of the system according to the GBI-NASA Monitoring Program. RX J1826.2-1450/LS 5039 continues to display moderate radio variability with a clearly non-thermal spectral index. No strong radio outbursts have been detected after several months.

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We present the results of analyzing H$\alpha$ spectra of the radio emitting X-ray binary LS I+61303. For the first time, the same 26.5 d radio period is clearly detected in the H$\alpha$ emission line. Moreover, the equivalent width and the peak separation of the H$\alpha$ emission line seem also to vary over a time scale of 1600 days. This points towards the $\sim4$ yr modulation, detected in the radio outburst amplitude, being probably a result of variations in the mass loss rate of the Be star and/or density variability in the circumstellar disk. In addition, the dependence of the peak separation from the equivalent width informs us that the LS I+61303 circumstellar disk is among the densest of Be-stars.

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The aim of this study is to evaluate the crystal structure of binary mixtures of palm kernel fat and fish oil, before and after chemical and enzymatic interesterification. The crystal structure was analyzed by polarized light microscopy. The addition of fish oil didn't change the palm kernel fat crystallization characteristics, spherullites of types A and B being observed. However, due to chemical and enzymatic interesterification, smaller crystals were obtained. There was no difference between chemical and enzymatic interesterification, probably as a function of acyl migration in discontinuous processes catalyzed by lipases.

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BACKGROUND: In the context of population aging, visual impairment has emerged as a growing concern in public health. However, there is a need for further research into the relationship between visual impairment and chronic medical conditions in the elderly. The aim of our study was to examine the relationship between visual impairment and three main types of co-morbidity: chronic physical conditions (both at an independent and additive level), mental health and cognitive functioning. METHODS: Data were collected from the COURAGE in Europe project, a cross-sectional study. A total of 4,583 participants from Spain were included. Diagnosis of chronic medical conditions included self-reported medical diagnosis and symptomatic algorithms. Depression and anxiety were assessed using CIDI algorithms. Visual assessment included objective distance/near visual acuity and subjective visual performance. Descriptive analyses included the whole sample (n = 4,583). Statistical analyses included participants aged over 50 years (n = 3,625; mean age = 66.45 years) since they have a significant prevalence of chronic conditions and visual impairment. Crude and adjusted binary logistic regressions were performed to identify independent associations between visual impairment and chronic medical conditions, physical multimorbidity and mental conditions. Covariates included age, gender, marital status, education level, employment status and urbanicity. RESULTS: The number of chronic physical conditions was found to be associated with poorer results in both distance and near visual acuity [OR 1.75 (CI 1.38-2.23); OR 1.69 (CI 1.27-2.24)]. At an independent level, arthritis, stroke and diabetes were associated with poorer distance visual acuity results after adjusting for covariates [OR 1.79 (CI 1.46-2.21); OR 1.59 (CI 1.05-2.42); OR 1.27 (1.01-1.60)]. Only stroke was associated with near visual impairment [OR 3.01 (CI 1.86-4.87)]. With regard to mental health, poor subjective visual acuity was associated with depression [OR 1.61 (CI 1.14-2.27); OR 1.48 (CI 1.03-2.13)]. Both objective and subjective poor distance and near visual acuity were associated with worse cognitive functioning. CONCLUSIONS: Arthritis, stroke and the co-occurrence of various chronic physical diseases are associated with higher prevalence of visual impairment. Visual impairment is associated with higher prevalence of depression and poorer cognitive function results. There is a need to implement patient-centered care involving special visual assessment in these cases.

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Solid-state MBz compounds, where M stands for bivalent Mn, Fe, Co, Ni, Cu and Zn and Bz is benzoate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The procedure used in the preparation of the compounds via reaction of basic carbonates with benzoic acid is not efficient in eliminating excess acid. However the TG-DTA curves permitted to verify that the binary compounds can be obtained by thermosynthesis, because the benzoic acid can be eliminated before the thermal decomposition of these compounds. The results led to information about the composition, dehydration, thermal stability, thermal decomposition and structure of the isolated compounds. On heating, these compounds decompose in two (Mn, Co, Ni, Zn) or three (Fe, Cu) steps with formation of the respective oxide (Mn3O4, Fe2O3, Co3O4, NiO, CuO and ZnO) as final residue. The theoretical and experimental spectroscopic studies suggest a covalent bidentate bond between ligand and metallic center.

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BACKGROUND: In the context of population aging, multimorbidity has emerged as a growing concern in public health. However, little is known about multimorbidity patterns and other issues surrounding chronic diseases. The aim of our study was to examine multimorbidity patterns, the relationship between physical and mental conditions and the distribution of multimorbidity in the Spanish adult population. METHODS: Data from this cross-sectional study was collected from the COURAGE study. A total of 4,583 participants from Spain were included, 3,625 aged over 50. An exploratory factor analysis was conducted to detect multimorbidity patterns in the population over 50 years of age. Crude and adjusted binary logistic regressions were performed to identify individual associations between physical and mental conditions. RESULTS: THREE MULTIMORBIDITY PATTERNS ROSE: 'cardio-respiratory' (angina, asthma, chronic lung disease), 'mental-arthritis' (arthritis, depression, anxiety) and the 'aggregated pattern' (angina, hypertension, stroke, diabetes, cataracts, edentulism, arthritis). After adjusting for covariates, asthma, chronic lung disease, arthritis and the number of physical conditions were associated with depression. Angina and the number of physical conditions were associated with a higher risk of anxiety. With regard to multimorbidity distribution, women over 65 years suffered from the highest rate of multimorbidity (67.3%). CONCLUSION: Multimorbidity prevalence occurs in a high percentage of the Spanish population, especially in the elderly. There are specific multimorbidity patterns and individual associations between physical and mental conditions, which bring new insights into the complexity of chronic patients. There is need to implement patient-centered care which involves these interactions rather than merely paying attention to individual diseases.

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In this study a new approach, solid phase micro extraction (SPME), is used in the evaluation of the infinite dilution activity coefficient of the solute in a given solvent. It is the purpose of the current work to demonstrate a different approach to obtain the data needed for studying the solution thermodynamics of binary liquid mixtures as well as for designing multi-component separations. The solutes investigated at the temperature 298.15 K were toluene, ethyl benzene and xylene in the solvent methanol.

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The purpose of this study is to analyze the interactions that occur in binary and ternary fat blends between medium and long chain triacylglycerols and their structured lipids obtained by chemical interesterification through the analysis of their physico-chemical properties. The synthesized structured triacylglycerols presented from 14.8 to 58.4% medium chain fatty acids, from 15.7 to 37.2% saturated fatty acids, from 19.2 to 47.5% monounsaturated fatty acids, and from 6.7 to 15.2% essential fatty acids. Chemical interesterification modified the behavior of binary and ternary mixtures and new types of triacylglycerol groups were formed.

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The aim of this study was to evaluate the crystallization behavior of binary mixtures of lard and soybean oil in different ratios and their respective structured lipids obtained by chemical interesterification. Crystallization kinetics and polarized light microscopy were used to analyze the mixtures before and after interesterification. The addition of soybean oil changed the lard crystallization, by the effect of the dilution. Crystal diameter increased, while the number of crystals decreased, as a function of temperature. Interesterification resulted in the formation of fewer crystals, with larger diameter in comparison with the original mixtures.

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Fluent health information flow is critical for clinical decision-making. However, a considerable part of this information is free-form text and inabilities to utilize it create risks to patient safety and cost-­effective hospital administration. Methods for automated processing of clinical text are emerging. The aim in this doctoral dissertation is to study machine learning and clinical text in order to support health information flow.First, by analyzing the content of authentic patient records, the aim is to specify clinical needs in order to guide the development of machine learning applications.The contributions are a model of the ideal information flow,a model of the problems and challenges in reality, and a road map for the technology development. Second, by developing applications for practical cases,the aim is to concretize ways to support health information flow. Altogether five machine learning applications for three practical cases are described: The first two applications are binary classification and regression related to the practical case of topic labeling and relevance ranking.The third and fourth application are supervised and unsupervised multi-class classification for the practical case of topic segmentation and labeling.These four applications are tested with Finnish intensive care patient records.The fifth application is multi-label classification for the practical task of diagnosis coding. It is tested with English radiology reports.The performance of all these applications is promising. Third, the aim is to study how the quality of machine learning applications can be reliably evaluated.The associations between performance evaluation measures and methods are addressed,and a new hold-out method is introduced.This method contributes not only to processing time but also to the evaluation diversity and quality. The main conclusion is that developing machine learning applications for text requires interdisciplinary, international collaboration. Practical cases are very different, and hence the development must begin from genuine user needs and domain expertise. The technological expertise must cover linguistics,machine learning, and information systems. Finally, the methods must be evaluated both statistically and through authentic user-feedback.

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In this work carrier-facilitated transport of mercury(II) against its concentration gradient from aqueous 0.04 M hydrochloric acid solution across a liquid membrane containing isopropyl 2-[(isopropoxycarbothiolyl)disulfanyl]ethane thioate (IIDE) as the mobile carrier in chloroform has been investigated. Sodium thiocyanate solution (1.6 M) was the most efficient receiving phase agent among several aqueous reagents tested. Various parameters such as investigated. Under optimum conditions the transport of Hg(II) across the liquid membrane is more than 97% after 2.5 h. The carrier, IIDE, selectively and efficiently could able to transport Hg (II) ions in the presence of other associated metal ions in binary systems.

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A binary sampling flow analysis system equipped with gas diffusion cell was developed for NH4+ and/or NH2Cl determination in wastewater and disinfection products samples based on the Berthelot reaction of the NH2Cl diffused through the semi-permeable PTFE membrane. The effect of the analytical conditions related to the reaction and flow parameters were evaluated and N-NH4+ and N-NH2Cl were determined in concentration ranges from 0.17 to 5 mg L-1 and from 0.5 to 14.5 mg L-1, respectively. Limits of detection (3σ) of 50 and 140 µg L-1 for N-NH4+ and N-NH2Cl were calculated, respectively, and RSD of 5 and 2% were calculated for 10 consecutive determinations of N-NH4+ (1 and 3 mg L-1) and N-NH2Cl (3 and 9 mg L-1), respectively with 30 determinations h-1.