982 resultados para Ossat, Arnaud de (1536-1604)


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Simultaneous all angle collocations (SAACs) of microwave humidity sounders (AMSU-B and MHS) on-board polar orbiting satellites are used to estimate scan-dependent biases. This method has distinct advantages over previous methods, such as that the estimated scan-dependent biases are not influenced by diurnal differences between the edges of the scan and the biases can be estimated for both sides of the scan. We find the results are robust in the sense that biases estimated for one satellite pair can be reproduced by double differencing biases of these satellites with a third satellite. Channel 1 of these instruments shows the least bias for all satellites. Channel 2 has biases greater than 5 K, thus needs to be corrected. Channel 3 has biases of about 2 K and more and they are time varying for some of the satellites. Channel 4 has the largest bias which is about 15 K when the data are averaged for 5 years, but biases of individual months can be as large as 30 K. Channel 5 also has large and time varying biases for two of the AMSU-Bs. NOAA-15 (N15) channels are found to be affected the most, mainly due to radio frequency interference (RFI) from onboard data transmitters. Channel 4 of N15 shows the largest and time varying biases, so data of this channel should only be used with caution for climate applications. The two MHS instruments show the best agreement for all channels. Our estimates may be used to correct for scan-dependent biases of these instruments, or at least used as a guideline for excluding channels with large scan asymmetries from scientific analyses.

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The climates of the mid-Holocene (MH), 6,000 years ago, and of the Last Glacial Maximum (LGM), 21,000 years ago, have extensively been simulated, in particular in the framework of the Palaeoclimate Modelling Intercomparion Project. These periods are well documented by paleo-records, which can be used for evaluating model results for climates different from the present one. Here, we present new simulations of the MH and the LGM climates obtained with the IPSL_CM5A model and compare them to our previous results obtained with the IPSL_CM4 model. Compared to IPSL_CM4, IPSL_CM5A includes two new features: the interactive representation of the plant phenology and marine biogeochemistry. But one of the most important differences between these models is the latitudinal resolution and vertical domain of their atmospheric component, which have been improved in IPSL_CM5A and results in a better representation of the mid-latitude jet-streams. The Asian monsoon’s representation is also substantially improved. The global average mean annual temperature simulated for the pre-industrial (PI) period is colder in IPSL_CM5A than in IPSL_CM4 but their climate sensitivity to a CO2 doubling is similar. Here we show that these differences in the simulated PI climate have an impact on the simulated MH and LGM climatic anomalies. The larger cooling response to LGM boundary conditions in IPSL_CM5A appears to be mainly due to differences between the PMIP3 and PMIP2 boundary conditions, as shown by a short wave radiative forcing/feedback analysis based on a simplified perturbation method. It is found that the sensitivity computed from the LGM climate is lower than that computed from 2 × CO2 simulations, confirming previous studies based on different models. For the MH, the Asian monsoon, stronger in the IPSL_CM5A PI simulation, is also more sensitive to the insolation changes. The African monsoon is also further amplified in IPSL_CM5A due to the impact of the interactive phenology. Finally the changes in variability for both models and for MH and LGM are presented taking the example of the El-Niño Southern Oscillation (ENSO), which is very different in the PI simulations. ENSO variability is damped in both model versions at the MH, whereas inconsistent responses are found between the two versions for the LGM. Part 2 of this paper examines whether these differences between IPSL_CM4 and IPSL_CM5A can be distinguished when comparing those results to palaeo-climatic reconstructions and investigates new approaches for model-data comparisons made possible by the inclusion of new components in IPSL_CM5A.

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Group exhibition of artists books curated by Gregorio Magnani, including Frozen Tears I - III (2003-7). Including books by Kasper Andreasen, Linus Bill and Adrien Horni, blisterZine, Daniel Gustav Cramer, Arnaud Desjardin, Michael Dean, Karl Holmqvist, Louis Luthi, Sara MacKillop, Dan Mitchell, Kristen Mueller, Sophie Nys, Simon Popper, Preston is my Paris, Alessandro Roma, Karin Ruggaber, John Russell, Erik Steinbrecher, Peter Tillessen, Erik van der Weijde

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P>Modern sugarcane (Saccharum spp.) is the leading sugar crop and a primary energy crop. It has the highest level of `vertical` redundancy (2n = 12x = 120) of all polyploid plants studied to date. It was produced about a century ago through hybridization between two autopolyploid species, namely S. officinarum and S. spontaneum. In order to investigate the genome dynamics in this highly polyploid context, we sequenced and compared seven hom(oe)ologous haplotypes (bacterial artificial chromosome clones). Our analysis revealed a high level of gene retention and colinearity, as well as high gene structure and sequence conservation, with an average sequence divergence of 4% for exons. Remarkably, all of the hom(oe)ologous genes were predicted as being functional (except for one gene fragment) and showed signs of evolving under purifying selection, with the exception of genes within segmental duplications. By contrast, transposable elements displayed a general absence of colinearity among hom(oe)ologous haplotypes and appeared to have undergone dynamic expansion in Saccharum, compared with sorghum, its close relative in the Andropogonea tribe. These results reinforce the general trend emerging from recent studies indicating the diverse and nuanced effect of polyploidy on genome dynamics.

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Borgmeiermyia Townsend, 1935 is a small Neotropical genus of Tachinidae (Diptera) with four described species. Brief descriptions are given to the previously unknown females of B. brasiliana Townsend, 1935 and B. paraguayana Sehnal, 1998, and the male of B. peruana Arnaud, 1963. An identification key to the four known species is given, as well as comments on characters with intraspecific variation. Change of depository of the holotype of B. brasiliana from one institution to another is discussed and its current location is given. Also, the first host is recorded for the genus with the occurrence of B. paraguayana para-sitizing Phylloptera aff. ovalifolia Burmeister, 1839 (Orthoptera: Tettigoniidae: Phaneropterinae).

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Squamous cell carcinoma is a prevalent head and neck tumor with high mortality. We studied the role played by laminin alpha 1 chain peptide AG73 on migration, invasion, and protease activity of cells (OSCC) from human oral squamous cell carcinoma. Immunohistochemistry and immunofluorescence analyzed expression of laminin alpha 1 chain and MMP9 in oral squamous cells carcinoma in vivo and in vitro. Migratory activity of AG73-treated OSCC cells was investigated by monolayer wound assays and in chemotaxis chambers. AG73-induced invasion was assessed in Boyden chambers. Invasion depends on MMPs. Conditioned media from cells grown on AG73 was subjected to zymography. We searched for AG73 receptors related to these activities in OSCC cells. Immunofluorescence analyzed AG73induced colocalization of syndecan-1 and beta 1 integrin. Cells had these receptors silenced by siRNA, followed by treatment with AG73 and analysis of migration, invasion, and protease activity. Oral squamous cell carcinoma expresses laminin alpha 1 chain and MMP9. OSCC cells treated with AG73 showed increased migration, invasion, and protease activity. AG73 induced colocalization of syndecan-1 and beta 1 integrin. Knockdown of these receptors decreased AG73-dependent migration, invasion, and protease activity. Syndecan-1 and beta 1 integrin signaling downstream of AG73 regulate migration, invasion, and MMP production by OSCC cells.

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Cytokines (IL-6, IL-10, and TNF-alpha) are increased after exhaustive exercise in the retroperitoneal adipose tissue (RPAT) and mesenteric adipose tissue (MEAT). An exhaustive acute exercise protocol induces inflammation in adipose tissue that lasts 6 h after the exercise has ended. It is well-established that this protocol increases circulating plasma levels of non-esterified fatty acids (NEFAs) and lipopolysaccharides (LPS), compounds that are important in stimulating signaling via toll like receptor-4 (TLR-4) in different type cells. In the present study, we investigated the regulation of TLR-4 and DNA-binding of nuclear factor-kappa Bp65 (NF-kappa Bp65) in different depots of adipose tissue in rats after exhaustive exercise. Rats were killed by decapitation immediately (E0 group, n = 6), 2 (E2 group, n = 6), and 6 h (E6 group, n = 6) after the exhaustive exercise, which consisted of running on a treadmill (approximately 70% V(O2max)) for 50 min and then running at an elevated rate that increased at 1 m/min, until exhaustion. The control group (C group, n = 6) was not subjected to exercise. In RPAT, TLR-4, MYD-88, and IkB alpha increased in the E2 group after exercise. MYD-88 and TRAF6 remained increased in the E6 group in comparison with the control group. DNA-binding of NF-kappa Bp65 was not altered. In MEAT, TLR-4, MYD-88, TRAF6, and DNA-binding of NF-kappa Bp65 were increased only in the E6 group. In conclusion, we have shown that increases in pro-inflammatory cytokines in adipose tissue pads after exhaustive exercise may be mediated via TLR-4 signaling, leading to increases in NF-kappa Bp65 binding to DNA in MEAT. J. Cell. Physiol. 226: 1604-1607, 2011. (C) 2010 Wiley-Liss, Inc.

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This paper proves the existence of nontrivial solution for a class of quasilinear systems oil bounded domains in R(N), N >= 2, whose nonlinearity has a double criticality. The proof is based oil a linking theorem without the Palais-Smale condition.

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Two fundamental processes usually arise in the production planning of many industries. The first one consists of deciding how many final products of each type have to be produced in each period of a planning horizon, the well-known lot sizing problem. The other process consists of cutting raw materials in stock in order to produce smaller parts used in the assembly of final products, the well-studied cutting stock problem. In this paper the decision variables of these two problems are dependent of each other in order to obtain a global optimum solution. Setups that are typically present in lot sizing problems are relaxed together with integer frequencies of cutting patterns in the cutting problem. Therefore, a large scale linear optimizations problem arises, which is exactly solved by a column generated technique. It is worth noting that this new combined problem still takes the trade-off between storage costs (for final products and the parts) and trim losses (in the cutting process). We present some sets of computational tests, analyzed over three different scenarios. These results show that, by combining the problems and using an exact method, it is possible to obtain significant gains when compared to the usual industrial practice, which solve them in sequence. (C) 2010 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.

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A series of palladium(II) thiosaccharinates with triphenylphosphane (PPh(3)), bis(diphenylphosphanyl)methane (dppm), and bis(diphenylphosphanyl)ethane (dppe) have been prepared and characterized. From mixtures of thiosaccharin, Htsac, and palladium(II) acetylacetonate, Pd(acac)(2), the palladium(II) thiosaccharinate, Pd(tsac)(2) (tsac: thiosaccharinate anion) (1) was prepared. The reaction of I with PPh(3), dppm, and dppe leads to the mononuclear species Pd(tsac)(2)(PPh(3))(2)center dot MeCN (2), [Pd(tsac)(2)(dppm)] (3), Pd(tsac)(2)(dppm)(2) (4), and [Pd(tsac)(2)(dppe)]center dot MeCN (5). Compounds 2, 4, and 5 have been prepared also by the reaction of Pd(acac)(2) with the corresponding phosphane and Htsac. All the new complexes have been characterized by chemical analysis, UV/Vis, IR, and Raman spectroscopy. Some of them have been also characterized by NMR spectroscopy. The crystalline structures of complexes 3, and 5 have been studied by X-ray diffraction techniques. Complex 3 crystallizes in the monoclinic space group P2(1)/n with a = 16.3537(2), b = 13.3981(3), c = 35.2277(7) angstrom, beta = 91.284(1)degrees, and Z = 8 molecules per unit cell, and complex 5 in P2(1)/n with a = 10.6445(8), b = 26.412(3), c = 15.781(2) angstrom, beta = 107.996(7)degrees, and Z = 4. In compounds 3 and 5, the palladium ions are in a distorted square planar environment. They are closely related, having two sulfur atoms of two thiosaccharinate anions, and two phosphorus atoms of one molecule of dppm or dppe, respectively, bonded to the Pd(II) atom. The molecular structure of complex 3 is the first reported for a mononuclear Pd(II)-dppm-thionate system.

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Understanding the molecular basis of the binding modes of natural and synthetic ligands to nuclear receptors is fundamental to our comprehension of the activation mechanism of this important class of hormone regulated transcription factors and to the development of new ligands. Thyroid hormone receptors (TR) are particularly important targets for pharmaceuticals development because TRs are associated with the regulation of metabolic rates, body weight, and circulating levels of cholesterol and triglycerides in humans. While several high-affinity ligands are known, structural information is only partially available. In this work we obtain structural models of several TR-ligand complexes with unknown structure by docking high affinity ligands to the receptors` ligand binding domain with subsequent relaxation by molecular dynamics simulations. The binding modes of these ligands are discussed providing novel insights into the development of TR ligands. The experimental binding free energies are reasonably well-reproduced from the proposed models using a simple linear interaction energy free-energy calculation scheme.

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This work presents the optical properties of erbium-doped and erbium/ytterbium codoped Na(2)O-Al(2)O(3)-TiO(2)-Nb(2)O(5)-P(2)O(5) glass systems and also the characterization of planar waveguides obtained by typical thermally assisted Ag+<-> Na+ ion-exchange process. The glass systems allow the preparation of single mode and multimode planar waveguides presenting a strong and relatively broad emission at 1536 nm. The emission signal in the infrared region is intensified for silver-containing samples when compared with free-silver samples. The emission signal intensification may be attributed to a nonplasmonic energy transfer from silver species to Er3+ ions as no bands related to surface plasmon resonance (SPR) of silver nanoparticles were observed.

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We show how a circuit analysis, used widely in electrical engineering, finds application to problems of light wave injection and transport in subwavelength structures in the optical frequency range. Lumped circuit and transmission-line analysis may prove helpful in the design of plasmonic devices with standard, functional properties.

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Given a Lorentzian manifold (M,g), a geodesic gamma in M and a timelike Jacobi field Y along gamma, we introduce a special class of instants along gamma that we call Y-pseudo conjugate (or focal relatively to some initial orthogonal submanifold). We prove that the Y-pseudo conjugate instants form a finite set, and their number equals the Morse index of (a suitable restriction of) the index form. This gives a Riemannian-like Morse index theorem. As special cases of the theory, we will consider geodesics in stationary and static Lorentzian manifolds, where the Jacobi field Y is obtained as the restriction of a globally defined timelike Killing vector field.