980 resultados para Galaxies : Elliptical And Lenticular, Cd
Resumo:
Background and Objectives: To specify which of the documented cognitive and emotional deficits characterize adolescents with conduct disorder (CD) compared with high-risk controls. Methods: High-risk adolescent males with and without CD were compared on intellectual efficiency, cognitive flexibility, impulsivity, alexithymia, and cognitive coping strategies. Substance use was controlled for in analyses. Results: Both groups showed normal intellectual efficiency and cognitive flexibility, as weil as heightened alexithymia and bebavioral impulsivity. Youths with CD evidenced more self-defeating and black-and-white tbinking under stress, and more acting-out under negative affect, than those without CD. Conclusions: Deficits specifie to CD resided in facets of emotional functioning and cognitive coping that might be targeted by a coping skills intervention.
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BACKGROUND: Infliximab (IFX) has been used for over a decade worldwide. Less is known about the natural history of IFX use beyond a few years and which patients are more likely to sustain benefits. METHODS: Patients with Crohn's disease (CD) exposed to IFX from Massachusetts General Hospital, Boston, Saint-Antoine Hospital, Paris, and the Swiss IBD Cohort Study were identified through retrospective and prospective data collection, complemented by chart abstraction of electronic medical records. We compared long-term users of IFX (>5 yr of treatment, long-term users of infliximab [LTUI]), with non-LTUI patients to identify prognostic factors. RESULTS: We pooled data on 1014 patients with CD from 3 different databases, of whom 250 were defined as LTUI. The comparison group comprised 290 patients with CD who discontinued IFX: 48 primary nonresponses, 95 loss of responses, and 147 adverse events. Factors associated with LTUI were colonic involvements and an earlier age at the start of IFX. The prevalence of active smokers and obese patients differed markedly, but inversely, between American and European centers but did not impact outcome. The discontinuation rate was stable around 3% to 6%, each year from years 3 to 10. CONCLUSIONS: Young age at start of IFX and colonic CD are factors associated with a beneficial long-term use of IFX. After 5 years of IFX, there is still a 3% to 5% discontinuation rate annually. Several factors associated with a good initial response such as nonsmoker and shorter disease duration at IFX initiation do not seem associated with a longer term response.
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Complexation between acyclovir (ACV), an antiviral drug used for the treatment of herpes simplex virus infection, and beta-cyclodextrin (beta-CD) was studied in solution and in solid states. Complexation in solution was evaluated using solubility studies and nuclear magnetic resonance spectroscopy (¹H-NMR). In the solid state, X-ray diffraction, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and dissolution studies were used. Solubility studies suggested the existence of a 1:1 complex between ACV and beta-CD. ¹H-NMR spectroscopy studies showed that the complex formed occurs with a stoichiometry ratio of 1:1. Powder X-ray diffraction indicated that ACV exists in a semicrystalline state in the complexed form with beta-CD. DSC studies showed the existence of a complex of ACV with beta-CD. The TGA studies confirmed the DSC results of the complex. Solubility of ACV in solid complexes was studied by the dissolution method and it was found to be much more soluble than the uncomplexed drug.
Resumo:
Jundiaí river is the main stream in the Jundiaí Hydrographic Basin and its water is not considered safe for public supply. The water problem is getting worse with the development of the region. The Pirai stream, have been one of the last potable water resource. With the purpose of investigating the sediment quality, due to its influence on the water quality, bioavailable and total Cd and Pb were determined using TS-FF-AAS. Total Cd and Pb up to 2.47 and 24.7 µg g-1 were measured, respectively. The wastewater sludge showed concentrations of 4.01 and 171 µg g-1, for the same metals.
Resumo:
Voltammetric technique was used to study the binary and ternary complexes of cadmium with L-amino acids and vitamin-C (L-ascorbic acid) at pH =7.30 ± 0.01, µ = 1.0M KNO3 at 25ºC and 35ºC. Cd (II) formed 1:1:1, 1:1:2 and 1:2:1 complexes with L-lysine, L-ornithine, L-threonine, L-serine, L-phenylglycine, L-phenylalanine, L-glutamic acid and L-aspartic acid used as primary ligands and L-ascorbic acid used as secondary ligand. The trend of stability constant of complexes was L-lysine < L-ornithine < L-threonine < L-serine < L-phenylglycine < L-phenylalanine < L-glutamic acid < L-aspartic acid which can be explained on the basis of size, basicity and steric hindrance of ligands. The values of stability constant (log β) varied from 2.23 to11.33 confirm that these drugs i.e. L-amino acids or in combination with L-ascorbic acid or their complexes could be used against Cd (II) toxicity. The study has been carried out at 35ºC also to determine the thermodynamic parameters such as enthalpy change (ΔH), Free energy change (ΔG) and entropy change (ΔS) respectively.
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Aiming to provide insight and discussing the problems related to the diagnosis and differential diagnosis of canine transmissible venereal tumor (CTVT), especially in its extragenital form, immunohistochemical evaluation was performed and a comparison was established by analysis of the microscopic appearance of 10 genital CTVTs and 13 exclusively extragenital CTVTs previously diagnosed by cytology and histopathology. CTVTs samples were incubated with biotinylated antibodies raised against specific membrane (anti-macrophage) and cytoplasmic antigens (anti-lysozyme, anti-S-100 protein, anti-vimentin and anti-CD18) and subsequently developed using streptavidin-biotin peroxidase and streptavidin-biotin-alkaline phosphatase methods. A strong reactivity with the anti-vimentin antibody was found in 100% of the tumors tested (22/22). No reactivity was found for the anti-lysozyme, anti-macrophage, anti-S-100 protein and anti-CD18. No histopathological or immunoreactivity differences between genital and extragenital CTVTs were found. These findings do not corroborate the hypothesis of histiocytic origin of CTVT (no reactivity to anti-lysozyme, anti-macrophage and anti-CD 18 antibodies). In addition, the antibody panel used is useful to narrow the differential diagnosis for lymphomas, histiocytic tumors, amelanotic melanomas, and poorly differentiated epithelial neoplasias, among others.
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This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.
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Les métaux lourds (ML) s’accumulent de plus en plus dans les sols à l’échelle mondiale, d’une part à cause des engrais minéraux et divers produits chimiques utilisés en agriculture intensive, et d’autre part à cause des activités industrielles. Toutes ces activités génèrent des déchets toxiques qui s’accumulent dans l’environnement. Les ML ne sont pas biodégradables et leur accumulation cause donc des problèmes de toxicité des sols et affecte la biodiversité des microorganismes qui y vivent. La fertilisation en azote (N) est une pratique courante en agriculture à grande échelle qui permet d’augmenter la fertilité des sols et la productivité des cultures. Cependant, son utilisation à long terme cause plusieurs effets néfastes pour l'environnement. Par exemple, elle augmente la quantité des ML dans les sols, les nappes phréatiques et les plantes. En outre, ces effets néfastes réduisent et changent considérablement la biodiversité des écosystèmes terrestres. La structure des communautés des champignons mycorhiziens à arbuscules (CMA) a été étudiée dans des sols contaminés par des ML issus de la fertilisation à long terme en N. Le rôle des différentes espèces de CMA dans l'absorption et la séquestration des ML a été aussi investigué. Dans une première expérience, la structure des communautés de CMA a été analysée à partir d’échantillons de sols de sites contaminés par des ML et de sites témoins non-contaminés. Nous avons constaté que la diversité des CMA indigènes a été plus faible dans les sols et les racines des plantes récoltées à partir de sites contaminés par rapport aux sites noncontaminés. Nous avons également constaté que la structure de la communauté d'AMF a été modifiée par la présence des ML dans les sols. Certains ribotypes des CMA ont été plus souvent associés aux sites contaminés, alors que d’autres ribotypes ont été associés aux sites non-contaminés. Cependant, certains ribotypes ont été observés aussi bien dans les sols pollués que non-pollués. Dans une deuxième expérience, les effets de la fertilisation organique et minérale (N) sur les différentes structures des communautés des CMA ont été étudiés. La variation de la structure de la communauté de CMA colonisant les racines a été analysée en fonction du type de fertilisation. Certains ribotypes de CMA étaient associés à la fertilisation organique et d'autres à la fertilisation minérale. En revanche, la fertilisation minérale a réduit le nombre de ribotypes de CMA alors que la fertilisation organique l’a augmenté. Dans cette expérience, j’ai démontré que le changement de structure des communautés de CMA colonisant des racines a eu un effet significatif sur la productivité des plantes. Dans une troisième expérience, le rôle de deux espèces de CMA (Glomus irregulare et G. mosseae) dans l'absorption du cadmium (Cd) par des plants de tournesol cultivés dans des sols amendés avec trois niveaux différents de Cd a été évalué. J’ai démontré que les deux espèces de CMA affectent différemment l’absorption ou la séquestration de ce ML par les plants de tournesol. Cette expérience a permis de mieux comprendre le rôle potentiel des CMA dans l'absorption des ML selon la concentration de cadmium dans le sol et les espèces de CMA. Mes recherches de doctorat démontrent donc que la fertilisation en N affecte la structure des communautés des CMA dans les racines et le sol. Le changement de structure de la communauté de CMA colonisant les racines affecte de manière significative la productivité des plantes. J’ai aussi démontré que, sous nos conditions expériemntales, l’espèce de CMA G. irregulare a été observée dans tous les sites (pollués et non-pollués), tandis que le G. mosseae n’a été observé en abondance que dans les sites contaminés. Par conséquent, j’ai étudié le rôle de ces deux espèces (G. irregulare et G. mosseae) dans l'absorption du Cd par le tournesol cultivé dans des sols amendés avec trois différents niveaux de Cd en serre. Les résultats indiquent que les espèces de CMA ont un potentiel différent pour atténuer la toxicité des ML dans les plantes hôtes, selon le niveau de concentration en Cd. En conclusion, mes travaux suggèrent que le G. irregulare est une espèce potentiellement importante pour la phytoextration du Cd, alors que le G. mosseae pourrait être une espèce appropriée pour phytostabilisation du Cd et du Zn.
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Satellite cells, originating in the embryonic dermamyotome, reside beneath the myofibre of mature adult skeletal muscle and constitute the tissue-specific stem cell population. Recent advances following the identification of markers for these cells (including Pax7, Myf5, c-Met and CD34) (CD, cluster of differentiation; c-Met, mesenchymal epithelial transition factor) have led to a greater understanding of the role played by satellite cells in the regeneration of new skeletal muscle during growth and following injury. In response to muscle damage, satellite cells harbour the ability both to form myogenic precursors and to self-renew to repopulate the stem cell niche following myofibre damage. More recently, other stem cell populations including bone marrow stem cells, skeletal muscle side population cells and mesoangioblasts have also been shown to have myogenic potential in culture, and to be able to form skeletal muscle myofibres in vivo and engraft into the satellite cell niche. These cell types, along with satellite cells, have shown potential when used as a therapy for skeletal muscle wasting disorders where the intrinsic stem cell population is genetically unable to repair non-functioning muscle tissue. Accurate understanding of the mechanisms controlling satellite cell lineage progression and self-renewal as well as the recruitment of other stem cell types towards the myogenic lineage is crucial if we are to exploit the power of these cells in combating myopathic conditions. Here we highlight the origin, molecular regulation and therapeutic potential of all the major cell types capable of undergoing myogenic differentiation and discuss their potential therapeutic application.
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We present a catalogue of galaxy photometric redshifts and k-corrections for the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7), available on the World Wide Web. The photometric redshifts were estimated with an artificial neural network using five ugriz bands, concentration indices and Petrosian radii in the g and r bands. We have explored our redshift estimates with different training sets, thus concluding that the best choice for improving redshift accuracy comprises the main galaxy sample (MGS), the luminous red galaxies and the galaxies of active galactic nuclei covering the redshift range 0 < z < 0.3. For the MGS, the photometric redshift estimates agree with the spectroscopic values within rms = 0.0227. The distribution of photometric redshifts derived in the range 0 < z(phot) < 0.6 agrees well with the model predictions. k-corrections were derived by calibration of the k-correct_v4.2 code results for the MGS with the reference-frame (z = 0.1) (g - r) colours. We adopt a linear dependence of k-corrections on redshift and (g - r) colours that provide suitable distributions of luminosity and colours for galaxies up to redshift z(phot) = 0.6 comparable to the results in the literature. Thus, our k-correction estimate procedure is a powerful, low computational time algorithm capable of reproducing suitable results that can be used for testing galaxy properties at intermediate redshifts using the large SDSS data base.
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We describe a new spectroscopic technique for measuring radial metallicity gradients out to large galactocentric radii. We use the DEep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck telescope and the galaxy spectrum extraction technique of Proctor et al. We also make use of the metallicity sensitive near-infrared Calcium ii triplet (CaT) features together with single stellar population models to obtain metallicities. Our technique is applied as a pilot study to a sample of three relatively nearby (< 30 Mpc) intermediate-mass to massive early-type galaxies. Results are compared with previous literature inner region values and generally show good agreement. We also include a comparison with profiles from dissipational disc-disc major merger simulations. Based on our new extended metallicity gradients combined with other observational evidence and theoretical predictions, we discuss possible formation scenarios for the galaxies in our sample. The limitations of our new technique are also discussed.
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The triruthenium carboxylate cluster [Ru(3)O(OAc)(6)(py)(2)(bpp)](+) (OAc = acetate) containing the bridging 1,3-bis(4-pyridyl)propane (bpp) ligand, and its dimeric species [{Ru(3)O(OAc)(6)(py(2))}(2)(mu-bpp)](2+) were synthesized in order to investigate their inclusion compounds with beta-cyclodextrin (beta-CD). Characterization of the complexes was carried out based on spectroscopic, electrochemical and spectroelectrochemical techniques, while the formation of inclusion complexes was evaluated using (1)H NMR/NOESY spectroscopy. Since bpp is a flexible ligand, a DFT study was carried out in order to characterize its conformational isomers and their possible role in the host-guest chemistry with beta-CD. Instead of observing the formation of inclusion compounds with different stoichiometries, we observed the formation of 1:1 bpp/beta-CD compounds in which the bpp ligand assumes different conformations. The assembly of polymetallic rotaxane species was successfully demonstrated by monitoring the (1)H NMR spectra of the monomeric cluster species in the presence of aquapentacyanoferrate(II) ions and beta-CD.
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The electronic states of quantum rings with centerlines of arbitrary shape and non-uniform width in a threading magnetic field are calculated. The solutions of the Schrodinger equation with Dirichlet boundary conditions are obtained by a variational separation of variables in curvilinear coordinates. We obtain a width profile that compensates for the main effects of the curvature variations in the centerline. Numerical results are shown for circular, elliptical, and limacon-shaped quantum rings. We also show that smooth and tiny variations in the width may strongly affect the Aharonov-Bohm oscillations.
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In this study, non-nutrient heavy metal concentrations (Cd, Cr, Ni and Pb) were measured in composts during the composting process, in compost/Red-yellow Latosol mixtures, and in tomato plants. Composts were produced using sugar-cane bagasse, biosolids and cattle manure in the proportions 75-0-25, 75-12.5-12.5, 75-25-0, 50-50-0 or 0-100-0 (composts with 0, 12.5, 25, 50 and 100% biosolids). The composts were applied to the soil, in 6 treatments and a control (mineral fertilization). Control and the 0% biosolids treatments received inorganic nitrogen and all the treatments received the same amount of N, P and K. Tomato plants were cultivated in 24-L pots, in a green house in Jaboticabal, SP, Brazil. The experiment had a split plot design, in randomized blocks. Cadmium, Cr, Ni and Pb concentrations were determined during the composting process (7, 27, 57, 97 and 127 days after compost mounting), in soil (0 and 164 days after mixing) and plants. The samples were subjected to digestion with HNO 3, H2O2 and HCl and the metals were determined by AAS. Negative correlations were observed between Cd, Cr and Pb in the compost and Cd, Cr and Pb plant uptake, as well as Ni in the compost and Ni concentration in the plants. The concentrations of Cd, Cr, Ni and Pb increased during composting. Only Cd levels increased when compost was applied to the soil. The roots accumulated Cr, Ni and Pb, the stems and leaves, Cd and Ni and the fruits did not accumulate any of the metals studied. The composts with biosolids did not increase Cd, Cr, Ni and Pb uptake by plants.
Resumo:
This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m2 mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.