Phenotypic Characterization of Chicken Bursal Stromal Elements

Many, if not all, of the different phases of intrabursal B-cell maturation are controlled by the stromal components. We have used an extensive panel of mAb to provide a detailed phenotypic profile of these cells. Antigenic specificities were defined for the entire surface epithelium, interfollicular surface epithelium, follicle-associated epithelium, basement membrane, basement membrane-associated epithelium. Several mAb were specific for the medulla, including those reactive with the stellate network of epithelial cells, isolated macrophages, and granular, apparently secreted antigens. One of these, MUI-92, appears to be bursa-specific. Two mAb reacted strongly with stellate cortical macrophages, one of which weakly stained similar cells in the medulla. MHC-class II antigens were expressed on endothelium of the corticomedullary junction, macrophagelike cells in the cortex, and medulla and B lymphocytes predominantly in the cortex. Collectively, these mAb have demonstrated the antigenically distinct nature of discrete regions in the bursa, but also the continuity of the surface epithelium with the corticomedullary junction and medulla. They represent excellent reagents for defining the stromal cell contribution to B-cell development

Utilisation de l’ATP- Métrie comme Mesure Instantanée de la Qualité de l’Eau dans un Système de Collecte des Eaux de Pluie

L’ATP-Métrie, par l’analyse instantanée de l’ATP libre, de l’ATP Total et par conséquent de l’ATP Microbien (ATP Total — ATP libre), permet une évaluation rapide de la quantité de cellules vivantes, de particules non microbiennes et de particules microbiennes dans un échantillon d’eau. Lors des deux visites sur site des installations de l’Entreprise Sociale Tatirano concernant le système de récupération d’eau de pluie dans le Sud Est de Madagascar, côté Fort-Dauphin, une recherche de remplacement des analyses longues a été menée. Il s’agissait du comptage des colonies de coliformes thermotolérants (TTC) par des analyses rapides d’ATP libre et d’ATP Total ; et l’analyse du chlore libre (CLR), du chlore total (CTR) par les mesures des solides dissouts totaux (SDT) et de la conductivité électrique (CE). 10 variables avec 32 échantillons analysés ont été regroupées en une base de données. Une analyse en composantes principales a été réalisée pour identifier une première tendance générale de la relation entre les variables. Ensuite, une analyse détaillée des proximités des groupes identifiés a été effectuée avec la matrice de similarité des coefficients de corrélation de Pearson et de Spearman. Globalement, à l’issue de l’analyse en composantes principales, 4 axes principaux sont identifiés permettant d’interpréter 88,4 % des données. En combinant l’analyse des cosinus carrés des variables avec la représentation graphique sur le biplot, 2 groupes naturels sont observés. D’abord, l’ATP libre, l’ATP Total, l’ATP Microbien, TTC et le Log(TTC) sont principalement portés par l’axe 1. Puis, le CLR, le CTR, le SDT et la CE sont principalement portés par l’axe 2. Dans l’analyse détaillée de chaque groupe, une faible corrélation linéaire et une corrélation monotone positive et modérée sont observées entre l’ATP microbien et le TTC dont le Rho de Pearson 0,142, p=0,445, et le Rho de Spearman 0,403, p=0,025. Une corrélation linéaire modérée et une corrélation monotone positive et modérée sont observées entre l’ATP microbien et le Log (TTC) dont le Rho de Pearson 0,392, p=0,029, et le Rho de Spearman 0,403, p=0,025. Puis, il a été montré qu’il y a une corrélation linéaire modérée négative entre le CE, le CTR et le CLR, avec un Rho de Pearson -0,346, p=0,056 et un Rho de Spearman de -0,422, p=0,018. Une corrélation linéaire modérée négative a également été observée entre le SDT, le CTR et le CLR dont le Rho de Pearson est -0,369, p=0,041 et le Rho de Spearman -0,521, p=0,003. Ces résultats montrent que les valeurs mesurées instantanément par l’ATP-Métrie telles que l’ATP libre et l’ATP Total combinées à la mesure des STD et CE permettent une lecture instantanée d’un niveau de qualité de l’eau comparable à d’autres appareils de mesure. À ce stade, cela peut être utilisé comme une pré-analyse pour identifier une tendance avant des analyses de plus longues durées. La raison est que certains contextes tels que le niveau réel de pollution de l’eau (matières organiques et inorganiques) n’ont pas été pris en compte. Cela permet également de conclure que la valeur calculée de l’ATP Microbien ne peut pas encore être utilisée et interprétée comme des éléments de mesure de la qualité de l’eau

Formation and structural chemistry of the unusual cyanide-bridged dinuclear species [Ru-2(NN)(2)(CN)(7)](3-)(NN=2,2 '-bipyridine or 1,10-phenanthroline)

Crystallisation of simple cyanoruthenate complex anions [Ru(NN)(CN)(4)](2) (NN = 2,2'-bipyridine or 1,10-phenanthroline) in the presence of Lewis-acidic cations such as Ln(III) or guanidinium cations results, in addition to the expected [Ru(NN)(CN)(4)](2) salts, in the formation of small amounts of salts of the dinuclear species [Ru-2(NN)(2)(CN)(7)](3). These cyanide-bridged anions have arisen from the combination of two monomer units [Ru(NN)(CN)(4)](2) following the loss of one cyanide, presumably as HCN. The crystal structures of [Nd(H2O)(5.5)][Ru-2(bipy)(2)(CN)(7)] center dot 11H(2)O and [Pr(H2O)(6)][Ru-2(phen)(2)(CN)(7)] center dot 9H(2)O show that the cyanoruthenate anions form Ru-CN-Ln bridges to the Ln(III) cations, resulting in infinite coordination polymers consisting of fused Ru(2)Ln(2)(mu-CN)(4) squares and Ru(4)Ln(2)(mu-CN)(6) hexagons, which alternate to form a one-dimensional chain. In [CH6N3](3)[Ru-2(bipy)(2)(CN)(7)] center dot 2H(2)O in contrast the discrete complex anions are involved in an extensive network of hydrogen-bonding involving terminal cyanide ligands, water molecules, and guanidinium cations. In the [Ru-2(NN)(2)(CN)(7)](3) anions themselves the two NN ligands are approximately eclipsed, lying on the same side of the central Ru-CN-Ru axis, such that their peripheries are in close contact. Consequently, when NN = 4,4'-Bu-t(2)-2,2'-bipyridine the steric bulk of the t-butyl groups prevents the formation of the dinuclear anions, and the only product is the simple salt of the monomer, [CH6N3](2)[Ru((t)Bu(2)bipy)(CN)(4)] center dot 2H(2)O. We demonstrated by electrospray mass spectrometry that the dinuclear by-product [Ru-2(phen)(2)(CN)(7)](3) could be formed in significant amounts during the synthesis of monomeric [Ru(phen)(CN)(4)](2) if the reaction time was too long or the medium too acidic. In the solid state the luminescence properties of [Ru-2(bipy)(2)(CN)(7)](3) (as its guanidinium salt) are comparable to those of monomeric [Ru(bipy)(CN)(4)](2), with a (MLCT)-M-3 emission at 581 nm

Jet aircraft engine exhaust emissions database development: Year 1990 and 2015 scenarios

Studies relating to environmental emissions associated with the High Speed Civil Transport (HSCT) military jet and charter jet aircraft were conducted by McDonnell Douglas Aerospace Transport Aircraft. The report includes engine emission results for baseline 1990 charter and military scenario and the projected jet engine emissions results for a 2015 scenario for a Mach 1.6 HSCT charter and military fleet. Discussions of the methodology used in formulating these databases are provided

Phenotypic Characterization of Chicken Thymic Stromal Elements

Phenotypic profiles of the thymic stromal components provide an excellent approach to elucidating the nature of the microenvironment of this organ. To address this issue in chickens, we have produced an extensive panel of 18 mAb to the thymic stroma. These mAb have been extensively characterized with respect to their phenotypic specificities and reveal that the stromal cells are equally as complex as the T cells whose maturation they direct. They further demonstrate that, in comparison to the mammalian thymus, there is a remarkable degree of conservation in thymic architecture between phylogenetically diverse species. Eleven mAb reacted with thymic epithelial cells: MUI-73 was panepithelium, MUI-54 stained all cortical and medullary epithelium but only a minority of the subcapsule, MUI-52 was specific for isolated stellate cortical epithelial cells, MUI-62, -69, and -71 were specific for the medulla (including Hassall’s corpusclelike structures), MUI-51, -53, -70, and -75 reacted only with the type-I epithelium, or discrete regions therein, lining the subcapsular and perivascular regions and MUI-58 demonstrated the antigenic similarity between the subcapsule and the medulla. Seven other mAb identified distinct isolated stromal cells throughout the cortex and medulla. Large thymocyte-rich regions, which often spanned from the outer cortex to medulla, lacked epithelial cells. These mAb should prove invaluable for determining the functional significance of thymic stromal-cell subsets to thymopoiesis

Exploring excited states of Pt(ii) diimine catecholates for photoinduced charge separation

The intense absorption in the red part of the visible range, and the presence of a lowest charge-transfer excited state, render Platinum(II) diimine catecholates potentially promising candidates for light-driven applications. Here, we test their potential as sensitisers in dye-sensitised solar cells and apply, for the first time, the sensitive method of photoacoustic calorimetry (PAC) to determine the efficiency of electron injection in the semiconductor from a photoexcited Pt(II) complex. Pt(II) catecholates containing 2,2′-bipyridine-4,4′-di-carboxylic acid (dcbpy) have been prepared from their parent iso-propyl ester derivatives, complexes of 2,2′-bipyridine-4,4′-di-C(O)OiPr, (COOiPr)2bpy, and their photophysical and electrochemical properties studied. Modifying diimine Pt(II) catecholates with carboxylic acid functionality has allowed for the anchoring of these complexes to thin film TiO2, where steric bulk of the complexes (3,5-ditBu-catechol vs. catechol) has been found to significantly influence the extent of monolayer surface coverage. Dye-sensitised solar cells using Pt(dcbpy)(tBu2Cat), 1a, and Pt(dcbpy)(pCat), 2a, as sensitisers, have been assembled, and photovoltaic measurements performed. The observed low, 0.02–0.07%, device efficiency of such DSSCs is attributed at least in part to the short excited state lifetime of the sensitisers, inherent to this class of complexes. The lifetime of the charge-transfer ML/LLCT excited state in Pt((COOiPr)2bpy)(3,5-di-tBu-catechol) was determined as 250 ps by picosecond time-resolved infrared spectroscopy, TRIR. The measured increase in device efficiency for 2a over 1a is consistent with a similar increase in the quantum yield of charge separation (where the complex acts as a donor and the semiconductor as an acceptor) determined by PAC, and is also proportional to the increased surface loading achieved with 2a. It is concluded that the relative efficiency of devices sensitised with these particular Pt(II) species is governed by the degree of surface coverage. Overall, this work demonstrates the use of Pt(diimine)(catecholate) complexes as potential photosensitizers in solar cells, and the first application of photoacoustic calorimetry to Pt(II) complexes in general

Development of CCDs for REXIS on OSIRIS-REx

The Regolith x-ray Imaging Spectrometer (REXIS) is a coded-aperture soft x-ray imaging instrument on the OSIRIS-REx spacecraft to be launched in 2016. The spacecraft will fly to and orbit the near-Earth asteroid Bennu, while REXIS maps the elemental distribution on the asteroid using x-ray fluorescence. The detector consists of a 2×2 array of backilluminated 1k×1k frame transfer CCDs with a flight heritage to Suzaku and Chandra. The back surface has a thin p[superscript +]-doped layer deposited by molecular-beam epitaxy (MBE) for maximum quantum efficiency and energy resolution at low x-ray energies. The CCDs also feature an integrated optical-blocking filter (OBF) to suppress visible and near-infrared light. The OBF is an aluminum film deposited directly on the CCD back surface and is mechanically more robust and less absorptive of x-rays than the conventional free-standing aluminum-coated polymer films. The CCDs have charge transfer inefficiencies of less than 10[superscript -6], and dark current of 1e-/pixel/second at the REXIS operating temperature of –60 °C. The resulting spectral resolution is 115 eV at 2 KeV. The extinction ratio of the filter is ~10[superscript 12] at 625 nm.United States. National Aeronautics and Space Administration. Strategic Astrophysics Technology Program (Grant NNX12AF22G)United States. National Aeronautics and Space Administration (Contract NNG12FD70C)United States. National Aeronautics and Space Administration (IPR NNG12FC01I)United States. National Aeronautics and Space Administration. Strategic Astrophysics Technology Program (IPR NNH12AU04I)United States. Air Force (Contract FA8721-05-C-0002