220 research outputs found
Postembrional development of the feral pigeon (Columba livia) nestlings in an urbanized territory
Ontogenesis of the feral pigeons, Columba livia, was investigated in the territory of the city of Kazan. Nestlings of summer generation of one laying were shown to hatch with a diurnal interval, nestlings of spring, autumn, and winter generations with an interval of 3-4 h. There are five stages in the development of feral pigeon nestlings. Three stages falls on the nesting period, the fourth period covers the end and partly the postnesting one, and the fifth stage corresponds to the postnesting period. The maximal growth rate is characteristic of the first three days of postembryogenesis. The greatest increment of the mass and increase in the linear sizes of nestlings occurred in the first half of postembryogenesis. By the moment of hatching, some parts of the body are formed to a different degree, therefore, the rate of their development is also different. The highest rate of the growth was in the body parts that began functioning earlier than the others. By the end of the nesting period, the upper and lower tips and the length of the secondaries reach the definite sizes. The linear sizes of the body and feathering continue growing during the postnesting period
The effects of disorder in dimerized quantum magnets in mean field approximations
We study theoretically the effects of disorder on Bose-Einstein condensates
(BEC) of bosonic triplon quasiparticles in doped dimerized quantum magnets. The
condensation occurs in a strong enough magnetic field Hc, where the
concentration of bosons in the random potential is sufficient to form the
condensate. The effect of doping is partly modeled by delta - correlated
disorder potential, which (i) leads to the uniform renormalization of the
system parameters and (ii) produces disorder in the system with renormalized
parameters. These approaches can explain qualitatively the available
magnetization data in the Tl_(1-x)K_(x)CuCl_3 compound taken as an example. In
addition to the magnetization, we found that the speed of the Bogoliubov mode
has a peak as a function of doping parameter, x. No evidence of the pure Bose
glass phase has been obtained in the BEC regime.Comment: Includes 19 pages, 5 figure
Formation of ions by high energy photons
We calculate the electron energy spectrum of ionization by a high energy
photon, accompanied by creation of electron-positron pair. The total cross
section of the process is also obtained. The asymptotics of the cross section
does not depend on the photon energies. At the photon energies exceeding a
certain value this appeares to to be the dominant mechanism of
formation of the ions. The dependence of on the value of nuclear
charge is obtained. Our results are consistent with experimental data.Comment: 16 pages, 6 figure
Experimental, Clinical and Morphological Analysis of H-Ras Oncoproteins for Locally Advanced Breast Cancer
BACKGROUND: Activated forms of Ras are enhanced in both breast cancer as well as the cell lines with EGFR and HER2 expression. Therefore, H-Ras could be activated in breast tumours in the absence of direct mutational activation of Ras itself and could contribute to 20-50% of the cases. Expression inhibition, signal transduction interruption from H-Ras to the nucleus could become a promising therapeutic target.
AIM: The aim of this study was to investigate the clinical and morphological criteria of locally advanced breast cancer and the expression of H-Ras oncoprotein in patients who have been subjected to different regimens of farnesyltransferase inhibitor.
METHODS: H-Ras status was assessed by immunohistochemistry (IHC).
RESULTS: An association between the expressions of H-Ras and Her2/neu (p = 0.001) as well as the tumour proliferation index Ki-67 (p = 0.001) in patients with breast cancer was established. Analysis of the relationship between H-Ras expression showed a relatively strong association with progression-free survival both before the treatment (V = 0.47; p = 0.001) and after the treatment (V = 0.45; p = 0.001). These results may indicate the clinical applicability of H-Ras as a prognostic factor or serve as a therapeutic target for breast cancer treatment.
CONCLUSION: These results could indicate the potential clinical application of H-Ras as a prognostic factor or a therapeutic target for breast cancer treatment
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