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11.
Fernandez T Suarez D Sordo JA Monnat F Roversi E Estrella De Castro A Schenk K Vogel P 《The Journal of organic chemistry》2000,65(16):5075-5076
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Let G be a directed graph on n vertices (single loops allowed) such that there are λ directed paths of length k from P to Q for any distinct pair of vertices (P, Q). We prove that if n > 2 and k > 2, G is regular. The regular case is also discussed. 相似文献
14.
Pabla?Aguirre Natalia?Mena Victoria?Tapia Miguel?Arredondo Marco?T?Nú?ezEmail author 《BMC neuroscience》2005,6(1):3
Background
Iron is necessary for neuronal function but in excess generates neurodegeneration. Although most of the components of the iron homeostasis machinery have been described in neurons, little is known about the particulars of their iron homeostasis. In this work we characterized the response of SH-SY5Y neuroblastoma cells and hippocampal neurons to a model of progressive iron accumulation. 相似文献15.
To reach their physical goals, future neutrino factories using muon decay aim at an overall flux precision of or better. We analytically study the QED radiative corrections to the neutrino differential distributions from muon decay.
Kinematic uncertainties due to the divergence of the muon beam are considered as well. The resulting corrections to the neutrino
flux turn out to be of order , safely below the required precision.
Received: 10 September 2002 / Revised version: 4 April 2003 / Published online: 2 June 2003
RID="a"
ID="a" e-mail: alicia@delta.ft.uam.es
RID="b"
ID="b" e-mail: mena@delta.ft.uam.es 相似文献
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Sonia Aguado-Ullate Octavio González-del Moral Alberto Hernán-Gómez Miguel Mena Cristina Santamaría 《Journal of organometallic chemistry》2011,696(25):4011-4017
The ability of the oxonitride [{Ti(η5-C5Me5)(μ-O)}3(μ3-N)] (1) to act as an organometallic ligand has been studied from both theoretical and experimental points of view. DFT calculations have allowed understanding the electronic structure of 1, and rationalizing its chemical behavior by comparison with the electronic structures of isoelectronic species [{Ti(η5-C5Me5)(μ-O)}3(μ3-CH)] and [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)]. Reactions of 1 with different inorganic molecules such as [Mo(CO)3(1,3,5-Me3C6H3)] or AlEt3 have confirmed the possibility of 1 to act as a tridentate or monodentate ligand to give the [{(CO)3Mo}(μ3-O)3{Ti3(η5-C5Me5)3(μ3-N)}] (2) and [{Et3Al}(μ3-O){(μ-O)2Ti3(η5-C5Me5)3(μ3-N)}] (3) complexes, respectively. Surprisingly, reactions of 1 with [M(CO)6] (M = Cr, Mo, W) complexes led to activate the μ3-N unit in 1 to afford the new compounds [Ti3(η5-C5Me5)3(μ-O)4{(NC)M(CO)5}]2 [M = Cr (4), Mo (5), W (6)]. Molecular structures of complexes 2-6 have been established by single crystal X-ray analysis. 相似文献
18.
Suarez E Nguyen HP Ortiz IP Lee KJ Kim SB Krzywinski J Schug KA 《Analytica chimica acta》2011,706(1):157-163
Malaria is a devastating mosquito-borne disease, which affects hundreds of millions of people each year. It is transmitted predominantly by Anopheles gambiae, whose females must be >10 days old to become infective. In this study, cuticular lipids from a laboratory strain of this mosquito species were analyzed using a mass spectrometry method to evaluate their utility for age, sex and mating status differentiation. Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS), in conjunction with an acenaphthene/silver nitrate matrix preparation, was shown to be 100% effective in classifying A. gambiae females into 1, 7–10, and 14 days of age. MALDI-MS analysis, supported by multivariate statistical methods, was also effective in detecting cuticular lipid differences between the sexes and between virgin and mated females. The technique requires further testing, but the obtained results suggest that MALDI-MS cuticular lipid spectra could be used for age grading of A. gambiae females with precision greater than with other available methods. 相似文献
19.
Lithium aluminates Li[Al(O-2,6-Me(2)C(6)H(3))R'(3)] (R' = Et, Ph) react with the μ(3)-alkylidyne oxoderivative ligands [{Ti(η(5)-C(5)Me(5))(μ-O)}(3)(μ(3)-CR)] [R = H (1), Me (2)] to afford the aluminum-lithium-titanium cubane complexes [{R'(3)Al(μ-O-2,6-Me(2)C(6)H(3))Li}(μ(3)-O)(3){Ti(η(5)-C(5)Me(5))}(3)(μ(3)-CR)] [R = H, R' = Et (5), Ph (7); R = Me, R' = Et (6), Ph (8)]. Complex 7 evolves with the formation of a lithium dicubane species and a Li{Al(μ-O-2,6-Me(2)C(6)H(3))Ph(3)}(2)] unit. 相似文献
20.
Mena ML Moreno-Gordaliza E Moraleja I Cañas B Gómez-Gómez MM 《Journal of chromatography. A》2011,1218(9):1281-1290
In this work a 2D electrophoretic separation procedure able to maintain the integrity of platinum-protein bonds has been developed. The method is based on the use of sequential OFFGEL isoelectric focussing (IEF) and PAGE. A systematic study of the reagents used for PAGE, for OFFGEL-IEF separation, and post-separation treatment of gels (such as enzymatic digestion and sample preparation for MS analysis) was tackled regarding their suitability for the identification of platinum binding proteins using standard proteins incubated with cisplatin. The distribution of platinum in high and low molecular weight fractions (separated by cut-off filters) was determined by ICP-MS, which allows evaluating platinum-protein bond stability under the conditions studied. SDS-PAGE in the absence of β-mercaptoethanol or dithiotreitol preserved the platinum-protein bonds. In addition, neither the influence of the electric field during the electrophoretic separation, nor the processes of fixing, staining and destaining of proteins in the gel did result in the loss of platinum from platinum binding proteins. SDS-PAGE under non-reducing conditions provides separation of platinum-binding proteins in very narrow bands with quantitative recoveries. Different amounts of platinum-bound proteins covering the range 0.3-2.0 μg were separated and mineralised for platinum determination, showing good platinum linearity. Limits of detection for a mixture of five standard proteins incubated with cisplatin were between the range of 2.4 and 13.9 pg of platinum, which were satisfactory for their application to biological samples. Regarding OFFGEL-IEF, a denaturing solution without thiourea and without dithiotreitol is recommended. The suitability of the OFFGEL-IEF for the separation of platinum binding proteins of a kidney cytosol was demonstrated. 相似文献