984 resultados para 123-765


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Crystal growth of melt-textured Nd-123 pseudo-crystals was investigated via an isothermal solidification with top-seeding technique under a 1%O2 in N2 atmosphere. Non-steady state solidification was observed at low undercooling, in contrast to an almost linear growth at higher undercooling. Similar to processing in air, the substitution of Nd/Ba was found to decrease from the seed position to the edge of the crystal. In addition, the volume fraction of Nd-422 particles decreased in the solid as solidification proceeded. As a result of these microstructural inhomogeneities, the critical temperature and the critical current density varied within the crystal even for samples processed isothermally, despite the narrow solid solution range of the Nd-123 phase under a reduced pO2 atmosphere.

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Thin films of nano-composite Y-Ba-Cu-O (YBCO) superconductors containing nano-sized, non-superconducting particles of Y2Ba 4CuMOx (M-2411 with M = Ag and Nb) have been prepared by the PLD technique. Electron backscatter diffraction (EBSD) has been used to analyze the crystallographic orientation of nano-particles embedded in the film microstructure. The superconducting YBa2Cu3O7 (Y-123) phase matrix is textured with a dominant (001) orientation for all samples, whereas the M-2411 phase exhibits a random orientation. Angular critical current measurements at various temperature (T) and applied magnetic field (B) have been performed on thin films containing different concentration of the M-2411 second phase. An increase in critical current density J c at T < 77 K and B < 6 T is observed for samples with low concentration of the second phase (2 mol % M-2411). Films containing 5 mol % Ag-2411 exhibit lower Jc than pure Y-123 thin films at all fields and temperatures. Samples with 5 mol % Nb-2411 show higher Jc(B) than phase pure Y-123 thin films for T < 77 K. © 2010 IOP Publishing Ltd.

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A new band in the odd proton nucleus I-123 is identified via in- beam gamma- ray spectroscopy using the N-14+Cd-116 reaction. This band shows up as doublets with the previously assigned pi g(7/2) circle times (nu h(11/2))(2) band. Possible configurations of the new band are discussed in the framework of the cranked shell model and the geometrical model. It is argued that the new band might be a chiral partner of the previously known pi g(7/2) circle times (nu h(11/2))(2) band.

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Background Moderate di?erences in e?cacy between adjuvant chemotherapy regimens for breast cancer are plausible, and could a? ect treatment choices. We sought any such di?erences.

Methods We undertook individual-patient-data meta-analyses of the randomised trials comparing: any taxane-plusanthracycline-based regimen versus the same, or more, non-taxane chemotherapy (n=44 000); one anthracyclinebased regimen versus another (n=7000) or versus cyclo phosphamide, methotrexate, and ?uorouracil (CMF; n=18 000); and polychemotherapy versus no chemotherapy (n=32 000). The scheduled dosages of these three drugs and of the anthracyclines doxorubicin (A) and epirubicin (E) were used to de? ne standard CMF, standard 4AC, and CAF and CEF. Log-rank breast cancer mortality rate ratios (RRs) are reported.

Findings In trials adding four separate cycles of a taxane to a ?xed anthracycline-based control regimen, extending treatment duration, breast cancer mortality was reduced (RR 0·86, SE 0·04, two-sided signi?cance [2p]=0·0005). In trials with four such extra cycles of a taxane counterbalanced in controls by extra cycles of other cytotoxic drugs, roughly doubling non-taxane dosage, there was no signi?cant di?erence (RR 0·94, SE 0·06, 2p=0·33). Trials with CMF-treated controls showed that standard 4AC and standard CMF were equivalent (RR 0·98, SE 0·05, 2p=0·67), but that anthracycline-based regimens with substantially higher cumulative dosage than standard 4AC (eg, CAF or CEF) were superior to standard CMF (RR 0·78, SE 0·06, 2p=0·0004). Trials versus no chemotherapy also suggested greater mortality reductions with CAF (RR 0·64, SE 0·09, 2p<0·0001) than with standard 4AC (RR 0·78, SE 0·09, 2p=0·01) or
standard CMF (RR 0·76, SE 0·05, 2p<0·0001). In all meta-analyses involving taxane-based or anthracycline-based regimens, proportional risk reductions were little a? ected by age, nodal status, tumour diameter or di?erentiation (moderate or poor; few were well di?erentiated), oestrogen receptor status, or tamoxifen use. Hence, largely independently of age (up to at least 70 years) or the tumour characteristics currently available to us for the patients selected to be in these trials, some taxane-plus-anthracycline-based or higher-cumulative-dosage anthracycline-based regimens (not requiring stem cells) reduced breast cancer mortality by, on average, about one-third. 10-year overall mortality di?erences paralleled breast cancer mortality di?erences, despite taxane, anthracycline, and other toxicities.

Interpretation 10-year gains from a one-third breast cancer mortality reduction depend on absolute risks without chemotherapy (which, for oestrogen-receptor-positive disease, are the risks remaining with appropriate endocrine therapy). Low absolute risk implies low absolute bene?t, but information was lacking about tumour gene expression markers or quantitative immunohistochemistry that might help to predict risk, chemosensitivity, or both.


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Fragment 3 :Col. 1 + vignette (très fragmentaires) : ?Col. 2 + vignette : chapitre 86 (formule pour prendre l'aspect d'une hirondelle). La vignette contient une hirondelle sur une butte.Col. 3 + vignette : chapitre 87 (formule pour prendre l'aspect d'un serpent-sata). La vignette montre un serpent à tête humaine. Col. 4 + vignette : chapitre 88 (formule pour faire une transformation en crocodile Sobek). La vignette montre une crocodile momiforme.Col. 5 + vignette : chapitre 89 (formule pour permettre que la ba atteigne son cadavre dans la nécropole). La vignette montre l'oiseau-ba volant au-dessus du cadavre allongé sur le lit funéraire.Col. 6 + vignette (fragmentaires) : chapitre 90 (?). La vignette montre le défunt debout les bras en avant.Fragment 2 :Col. 1 + vignette (fragmentaires) : ? Seul un morceau de la vignette est conservé où l'on voit une divinité debout.Col. 2 + vignette : chapitre 91 (formule pour ne pas retenir le ba du défunt dans la nécropole). La vignette montre le défunt debout devant son oiseau-ba.Col. 3 + vignette : chapitre 92 (formule pour ouvrir la tombe pour le ba et pour l'ombre du défunt pour sa sortie pendant le jour). La vignette représente le défunt devant une chapelle où l'on voit l'oiseau-ba.Col. 4 + vignette : chapitre 93 (formule pour ne pas permettre que le défunt ne traverse vers l'Orient dans la nécropole). La vignette représente une divinité assise sur une barque avec le signe de l'Orient.Col. 5 + vignette (voir cadre suivant) : début du chapitre 98 (formule pour aller chercher le bac dans le ciel). La vignette montre la proue de la barque.Fragment 1 (prend place au sein des fragments du cadre suivant Egyptien 122) :Col. 1 + vignette : chapitre 102 (formule pour descendre dans la barque). La vignette représente Rê assis sur sa barque.Col. 2 + vignette (fragmentaires) : ? La vignette laisse deviner une barque.

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