99 resultados para Vespasiano, Emperador de Roma, 9-79.


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Background: Mycobacterium tuberculosis, a causative agent of chronic tuberculosis disease, is widespread among some animal species too. There is paucity of information on the distribution, prevalence and true disease status of tuberculosis in Asian elephants (Elephas maximus). The aim of this study was to estimate the sensitivity and specificity of serological tests to diagnose M. tuberculosis infection in captive elephants in southern India while simultaneously estimating sero-prevalence. Methodology/Principal Findings: Health assessment of 600 elephants was carried out and their sera screened with a commercially available rapid serum test. Trunk wash culture of select rapid serum test positive animals yielded no animal positive for M. tuberculosis isolation. Under Indian field conditions where the true disease status is unknown, we used a latent class model to estimate the diagnostic characteristics of an existing (rapid serum test) and new (four in-house ELISA) tests. One hundred and seventy nine sera were randomly selected for screening in the five tests. Diagnostic sensitivities of the four ELISAs were 91.3-97.6% (95% Credible Interval (CI): 74.8-99.9) and diagnostic specificity were 89.6-98.5% (95% CI: 79.4-99.9) based on the model we assumed. We estimate that 53.6% (95% CI: 44.6-62.8) of the samples tested were free from infection with M. tuberculosis and 15.9% (97.5% CI: 9.8 - to 24.0) tested positive on all five tests. Conclusions/Significance: Our results provide evidence for high prevalence of asymptomatic M. tuberculosis infection in Asian elephants in a captive Indian setting. Further validation of these tests would be important in formulating area-specific effective surveillance and control measures.

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Objective: Human papillomavirus oncoproteins E6 and E7 down modulate Toll-like receptor (TLR) 9 expression in infected keratinocytes. We explored the status of expression and function of TLR7, TLR8, and TLR9 in primary human Langerhans cells (LCs) isolated from cervical tumors. Methodology: Single-cell suspensions were made from fresh tissues of squamous cell carcinoma (International Federation of Gynecology and Obstetrics stage IB2); myeloid dendritic cells were purified using CD1c magnetic activated cell separation kits. Langerhans cells were further flow sorted into CD1a(+)CD207(+) cells. Acute monocytic leukemia cell line THP-1-derived LCs (moLCs) formed the controls. mRNA from flow-sorted LCs was reverse transcribed to cDNA and TLR7, TLR8, and TLR9 amplified. Monocyte-derived Langerhans cells and cervical tumor LCs were stimulated with TLR7, TLR8, and TLR9 ligands. Culture supernatants were assayed for interleukin (IL) 1 beta, IL-6, IL-10, IL-12p70, interferon (IFN) alpha, interferon gamma, and tumor necrosis factor (TNF) alpha by Luminex multiplex bead array. Human papillomavirus was genotyped. Results: We have for the first time demonstrated that the acute monocytic leukemia cell line THP-1 can be differentiated into LCs in vitro. Although these moLCs. expressed all the 3 TLRs, tumor LCs expressed TLR7 and TLR8, but uniformly lacked TLR9. Also, moLCs secreted IL-6, IL-1 beta, and tumor necrosis factor alpha to TLR8 ligand and interferon alpha in response to TLR9 ligand; in contrast, tumor LCs did not express any cytokine to any of the 3 TLR ligands. Human papillomavirus type 16 was one of the common human papillomavirus types in all cases. Conclusions: Cervical tumor LCs lacked TLR9 expression and were functionally anergic to all the 3: TLR7, TLR8, and TLR9 ligands, which may play a crucial role in immune tolerance. The exact location of block(s) in TLR7 and TLR8 signaling needs to be investigated, which would have important immunotherapeutic implications.

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Reaction of cis-Cl2Pt(S(O)Me-2)(2)] with 1 equiv of sym-N,N',N `'-triarylguanidines, ArN=C(NHAr)(2) (sym = symmetrical; Ar = 2-MeC6H4 (LH22-tolyl), 2-(MeO)C6H4 (LH22-anisyl), 4-MeC6H4 (LH24-tolyl), 2,5-Me2C6H3 (LH22,5-xylyl), and 2,6-Me2C6H3 (LH22,6-xylyl)) in toluene under reflux condition for 3 h afforded cis- or trans-Cl2Pt(S(O)Me-2)(ArN=C(NHAr)(2))] (Ar = 2-MeC6H4 (1), 2-(MeO)C6H4 (2), 4-MeC6H4 (3), 2,5-h Me2C6H3 (4), and 2,6-Me2C6H3 (5), respectively) in 83-96% yield. Reaction of cis-Cl2Pt(S(O)Me-2)(2)] with 1 equiv of LH22-tolyl and LH24-tolyl in the presence of 1 equiv of NaOAc in methanol under reflux condition for 3 h afforded acetate-substituted products, cis-(AcO)ClPt(S(O)Me-2)(ArN=C(NHAr)(2))] (Ar = 2-MeC6H4 (6) and 4-MeC6H4 (7)) in 83% and 84% yields, respectively. Reaction of cis-Cl2Pt(S(O)Me-2)(2)] with 1 equiv of LH22-anisyl and LH22-tolyl in the presence of 1 equiv of NaOAc in methanol under reflux condition for 3 and 12 h afforded six-membered C,N] platinacycles, Pt{kappa(2)(C,N)-C6H3R-3(NHC(NHAr)(=NAr))-2}Cl(S(O)Me-2)] (Ar = 2-RC6H4; R = OMe (8) and Me (9)), in 92% and 79% yields, respectively. The new complexes have been characterized by analytical and spectroscopic techniques, and further the molecular structures of 1, 2, 4, 5, 6, and 8 have been determined by single-crystal X-ray diffraction. The platinum atom in 1, 4, and 5 exhibited the trans configuration, while that in 2, 6, and 8 exhibited the cis configuration. Complex 6 is shown to be the precursor for 9, and the former is suggested to transform to the latter possibly via an intramolecular C-H activation followed by elimination of AcOH. The solution behavior of new complexes has been studied by multinuclear NMR (H-1, Pt-195, and C-13) spectroscopy. The new complexes exist exclusively as a single isomer (trans (1 and 5) and cis (6 and 7)), a mixture of cis and trans isomers with the former isomer being predominant in the case of 2 and the latter isomer being predominant in the case of 3. Complex 5 in the trans form revealed the presence of one isomer at 0.007 mM concentration and two isomers in about 1.00:0.12 ratio at 0.154 mM concentration as revealed by H-1 NMR spectroscopy, and this has been ascribed to the restricted Pt-S bond rotation at higher concentration. Platinacycle 8 exists as one isomer, while 9 exists as a mixture of seven isomers in solution. The influence of steric factor, pi-acceptor property of the guanidine, subtle solid-state packing forces upon the configuration of the platinum atom, and the number of isomers in solution have been outlined. Factors that accelerate or slow down the cycloplatination reaction, the role of NaOAc, and a plausible mechanism of this reaction have been discussed.

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The reentrant low temperature phase of the perovskite manganite LaMnO3+delta (delta=0.22) has been investigated with ac susceptibility and dc magnetization studies. A critical examination of the memory effects in ac susceptibility leads us to the conclusion that the slow dynamics in the system is a consequence of collective relaxation processes resulting from interactions between ferromagnetic clusters, whose presence was indicated in earlier studies. Here, we postulate that the collective behavior is due to the existence of long-range (dipolar) interactions between the large ferromagnetic `superspins'. This is also confirmed by an abnormally large microscopic spin-flip time (similar to 10(-9) s) compared to a canonical spin glass. (C) 2013 Elsevier B.V. All rights reserved.

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We have benchmarked the maximum obtainable recognition accuracy on five publicly available standard word image data sets using semi-automated segmentation and a commercial OCR. These images have been cropped from camera captured scene images, born digital images (BDI) and street view images. Using the Matlab based tool developed by us, we have annotated at the pixel level more than 3600 word images from the five data sets. The word images binarized by the tool, as well as by our own midline analysis and propagation of segmentation (MAPS) algorithm are recognized using the trial version of Nuance Omnipage OCR and these two results are compared with the best reported in the literature. The benchmark word recognition rates obtained on ICDAR 2003, Sign evaluation, Street view, Born-digital and ICDAR 2011 data sets are 83.9%, 89.3%, 79.6%, 88.5% and 86.7%, respectively. The results obtained from MAPS binarized word images without the use of any lexicon are 64.5% and 71.7% for ICDAR 2003 and 2011 respectively, and these values are higher than the best reported values in the literature of 61.1% and 41.2%, respectively. MAPS results of 82.8% for BDI 2011 dataset matches the performance of the state of the art method based on power law transform.

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We determine the nature of coupled phonons in mixed crystal of Cs-0.9(NH4)(0.1)H2AsO4 using inelastic light scattering studies in the temperature range of 5 K to 300 K covering a spectral range of 60-1100 cm(-1). The phase transition in this system are marked by the splitting of phonon modes, appearance of new modes and anomalies in the frequency as well as linewidth of the phonon modes near transition temperature. In particular, we observed the splitting of symmetric (v(1)) and antisymmetric (v(3)) stretching vibrations associated with AsO4 tetrahedra below transition temperature (T-c(*) similar to 110 K) attributed to the lowering of site symmetry of AsO4 in orthorhombic phase below transition temperature. In addition, the step-up (hardening) and step-down (softening) of the AsO4 bending vibrations (v(4) (S9, S11) and v(2) (S6)) below transition temperature signals the rapid development of long range ferroelectric order and proton ordering. The lowest frequency phonon (S1) mode observed at similar to 92 cm(-1) shows anomalous blue shift (similar to 12 %) from 300 K to 5 K with no sharp transition near T-c(*) unlike other observed phonon modes signaling its potential coupling with the proton tunneling mode. (C) 2013 Author(s).

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ZnAl2O4:Dy3+ (1-9 mol%) nanophosphors were synthesized by a simple, cost effective and environmental friendly route using Euphorbia tirucalli plant latex. The structural properties and morphological features of the phosphors were well studied by PXRD, FTIR, SEM and TEM measurements. The luminescent properties of ZnAl2O4:Dy3+ (1-9 mol%) nanophosphors were investigated from the excitation and emission spectra. The phosphor performance was evaluated by color co-ordinates. The values were well located in the near white region as a result it was highly useful for the fabrication of green component in WLEDs. The average particle size was found to be similar to 9-18 nm and same was confirmed by TEM and Scherrer's method. The highest photoluminescence (PL) and thermoluminescence (TL) intensity was obtained to be similar to 7 mol% Dy3+ concentration. A single TL glow peak was recorded at 172 degrees C at a warming rate of 2.5 degrees Cs (1). The intensity at 172 degrees C peak increases linearly up to 1 kGy and after that it diminishes. PL intensity was studied with different plant latex concentration (2-8 ml) and highest PL intensity was recorded for similar to 8 ml. The optimized phosphor showed good reusability, low fading and wide range of linearity with gamma-dose hence the phosphor was quite useful in radiation dosimetry. (C) 2013 Elsevier B.V. All rights reserved.

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Ge2Sb2Te5 (GST) is well known for its phase change properties and applications in memory and data storage. Efforts are being made to improve its thermal stability and transition between amorphous and crystalline phases. Various elements are doped to GST to improve these properties. In this work, Se has been doped to GST to study its effect on phase change properties. Amorphous GST film crystallized in to rock salt (NaCl) type structure at 150 degrees C and then transformed to hexagonal structure at 250 degrees C. Interestingly, Se doped GST ((GST)(0.9)Se-0.1) film crystallized directly into hexagonal phase and the intermediate phase of NaCl is not observed. The crystallization temperature (T-c) of (GST)(0.9)Se-0.1 is around 200 degrees C, which is 50 degrees C higher than the T-c of GST. For (GST)(0.9)Se-0.1, the threshold switching occurs at about 4.5V which is higher than GST (3 V). Band gap (E-opt) values of as deposited films are calculated from Tauc plot which are 0.63 eV for GST and 0.66 eV for (GST)(0.9)Se-0.1. The E-opt decreases for the films annealed at higher temperatures. The increased T-c, E-opt, the contrast in resistance and the direct transition to hexagonal phase may improve the data readability and thermal stability in the Se doped GST film. (C) 2014 AIP Publishing LLC.

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Transition metal-free acylation of isoquinoline, quinoline, and quinoxaline derivatives has been developed employing a cross dehydrogenative coupling (CDC) reaction with aldehydes using substoichiometric amount of TBAB (tetrabutylammonium bromide, 30 mol %) and K2S2O8 as an oxidant. This intermolecular acylation of electron-deficient heteroarenes provides an easy access and a novel acylation method of heterocyclic compounds. The application of this CDC strategy for acylation strategy has been illustrated in synthesizing isoquinoline-derived natural products.

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A colorimetric and ``turn-on'' fluorescent chemosensor based on 1,9-pyrazoloanthrone specifically for cyanide and fluoride ion detection shows a remarkable solid state reaction when crystals of tetrabutylammonium cyanide and fluoride are brought in physical contact with 1,9-pyrazoloanthrone. X-ray crystal structures of 1,9-pyrazoloanthrone and complexes have been determined, and the ion sensing activity (detection limit of 0.2 and 2 ppb) has been inferred based on spectroscopic and structural features.

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N-Alkyl substituted pyrazoloanthrone derivatives were synthesized, characterized and tested for their in vitro inhibitory activity over c-Jun N-terminal kinase (JNK). Among the tested molecules, a few derivatives showed significant inhibitory activity against JNK with minimal off-target effect on other mitogen-activated protein kinase (MAP kinase) family members such as MEK1/2 and MKK3,6. These results suggested that N-alkyl (propyl and butyl) bearing pyrazoloanthrone scaffolds provide promising therapeutic inhibitors for JNK in regulating inflammation associated disorders.

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Close-packed helices with mixed hydrogen bond directionality are unprecedented in the structural chemistry of alpha-polypeptides. While NMR studies in solution state provide strong evidence for the occurrence of mixed helices in (beta beta)(n) and (alpha beta)(n) sequences, limited information is currently available in crystals. The peptide structures presented show the occurrence of C-11/C-9 helices in (alpha beta)(n) peptides. Transitions between C-11 and C-11/C-9 helices are observed upon varying the alpha-amino acid residue.

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The N-alkyl derivative of 1,9-pyrazoloanthrone has been synthesized, characterized and evaluated as a potent sensor for picric acid.