[en] The hyperfine structure in the six fine structure levels in the 3d⁴4p ⁶F term in ⁵¹V has been studied and the magnetic dipole interaction constants were determined employing Doppler-free saturation spectroscopy on vanadium atoms produced by sputtering in a hollow-cathode discharge. The drastic improvement that can be obtained in saturated absorption spectroscopy by modulating the pump beam at a high modulation frquency is clearly demonstrated in the present paper. For these high modulation frequencies a comparison with polarization spectroscopy showed that the intrinsic advantage in signal-to-noise ratio that polarization spectroscopy has at low modulation frequencies is essentially lost at higher modulation frequencies. Also, in this particular case, the effects of velocity changing collisions were rather small. Consequently the two methods were considered being equally powerful in the present measurement situation. (orig.)

No abstract available

[en] The deformed configuration mixing calculations performed in the framework of projected Hartree-Fock (HF) formalism lead to the indeterminacy of ground state shape for the nucleus ⁵¹V. Multiple HF solutions of almost equal deformation ( 10 b²) have been obtained within about 0.5 MeV of each other. This indicates lack of collectivity at shell closure. Because of the dominance of (f7/2) configuration in the low-lying states of ⁵¹V, except for the lowest J=3/2 and 9/2 states, large overlaps are obtained for the states projected from the above intrinsic states. The observed low-lying J=3/2 and 9/2 states of ⁵¹V are found to belong dominantly to the oblate and prolate K=3/2 intrinsic states respectively. The calculated spectra and B(E2) values are in good agreement As in other N=28 nuclei, besides the low-lying states of small intrinsic state is likely to exist quite low in the spectrum of ⁵¹V. B(E2) values for transitions between these highly deformed states have been calculated.(author)

No abstract available

[en] Line widths Δν₁/₂ of ⁵¹V n.m.r. signals of vanadyl-triisopropylate VO(OPrsup(i))₃ dissolved in tetrahydrofurane range from 10 to 610 Hz, increasing with decreasing temperature according to a theoretically proposed T-¹/² exp(E/RT) law, indicating that the molecular correlation time tausub(c) is the main factor influencing line widths in this system. With lowering of temperature, ⁵¹V-shielding decreases (the temperature gradient of the chemical shift deltasub(v) is about -0,5 ppm/K over a temperature range of 300-180 K),suggesting a loss of molecular symmetry due to solvation and association processes. In pentane, methylcyclohexane and diethylether, the deltsub(v)/T and Δν/₂/T correlations exhibit two inconsistencies at approximately 190 and 240 K which are attributed to the formation of clusters, and of oligomers (VO(OPrsup(i)₃)n, respectively. The latter gives rise to a satellite line with an upfield shift relative to the monomeric species. Exchange interactions are discussed as a second factor affecting line widths. (orig.)

[en] The calculations carried out on the nuclear properties of ⁵¹V in the framework of Hartree-Fock projection formalism with the band-mixing between the lowest four intrinsic states are reported. The effect of variation of the single particle energies in the pf-shell configuration space on the computed nuclear properties is also studied. The energy spectrum, static moments and the electromagnetic transitions in ⁵¹V are well accounted by the same set of single particle energies and the effective nucleon charges employed in earlier calculations on sup(47,49)V. (author)

[en] To date only a handful of drugs are available for the treatment of melanoma. Among them vemurafenib, a Braf"V"6"0"0"E specific inhibitor, showed promising results in terms of response rate and increase in median survival time. However, its effectiveness is limited by development of resistance and the search for additional drugs for melanoma treatment is ongoing. The present study was performed to analyze the correlation between Braf expression and the expression of p300, a known down stream target of the mitogen activated protein kinase (MAPK) pathway, which was recently shown by us to be a prognostic marker for melanoma progression and patient survival. The expression of Braf and p300 expression were correlated and analyzed by Chi-square test. A total of 327 melanoma patient cases (193 primary melanoma and 134 metastatic melanoma) were used for the study. Classification & regression tree (CRT), Kaplan-Meier, and multivariate Cox regression analysis were used to elucidate the significance of the combination of Braf and p300 expression in the diagnosis and prognosis of melanoma. Our results demonstrate that Braf expression is inversely correlated with nuclear p300 and positively correlated with cytoplasmic p300 expression. Braf and cytoplasmic p300 were found to be associated with melanoma progression, tumor size and ulceration status. CRT analysis revealed that a combination of Braf and p300 expression (nuclear and cytoplasmic), could be used to distinguish between nevi and melanoma, and primary from metastatic melanoma lesions. The combination of Braf and nuclear p300 was significantly associated with patient survival and nuclear p300 was found to be an independent predictor of patient survival. Our results indicate a cross-talk between Braf and p300 in melanoma and demonstrate the importance Braf and p300 expression in the diagnosis and prognosis of melanoma

[en] The basic difference between pairing-plus-surface-tensor-interaction and the realistic forces, namely the Kuo-Brown interaction is pointed out. The results of shell-model calculation of ⁵¹V is shown. (Auth.)

[en] The B¹1 and Vsup(51) spectra have been used to study the structure of glasses in the system V₂O₅-B₂O₃-Al₂O₃. The fraction of BO₄ units are measured that; (1)the boron atoms which are linked in the form of Al-O-B linkage are coordinated by four oxygens atoms; (2) the V₂O₅ does not effect the formation of BO₄ units. (Author)

No abstract available