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Stars with initial masses such that 10M[symbol: see text]
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This paper is a companion piece to our previous work [J. Stat. Phys. 119, 1283 (2005)], which introduced a generalized canonical ensemble obtained by multiplying the usual Boltzmann weight factor of the canonical ensemble with an exponential factor involving a continuous function of the Hamiltonian . We provide here a simplified introduction to our previous work, focusing now on a number of physical rather than mathematical aspects of the generalized canonical ensemble. The main result discussed is that, for suitable choices of , the generalized canonical ensemble reproduces, in the thermodynamic limit, all the microcanonical equilibrium properties of the many-body system represented by even if this system has a nonconcave microcanonical entropy function. This is something that in general the standard canonical ensemble cannot achieve. Thus a virtue of the generalized canonical ensemble is that it can often be made equivalent to the microcanonical ensemble in cases in which the canonical ensemble cannot. The case of quadratic functions is discussed in detail; it leads to the so-called Gaussian ensemble.
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Observations of the large-scale structure of the universe suggest inhomogeneities on scales between 100h-1 and 150h-1 Mpc (where h approximately 0.5-1 is the Hubble constant in units of 100 km.s-1.Mpc-1; 1 pc = 3.09 x 10(16) m). A deep redshift survey with a "pencil-beam" geometry of galaxies at the galactic poles indicated strong clustering, with a provocative regularity at 128h-1 Mpc [Broadhurst, T. J., Ellis, R. S., Koo, D. C. & Szalay, A. S. (1990) Nature (London) 343, 726-728]. Using newly acquired data, we demonstrate how multiple deep probes overcome most of the statistical problems associated with single pencil beams. Our results from cross correlations of multiple pencil beams, containing over 1200 galaxies, indicate that the strong peak in the power spectrum results from structures of large transverse size, in agreement with our original conjecture. We also discuss the sensitivity of pencil-beam surveys to the topology of large-scale structures and compare them with sparsely sampled wide-angle local surveys.
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The estrogen receptor protein content of recurrent breast cancer correlates well with the clinical response of hormonal manipulation. This predictive value of the ER of the primary tumor obtained at the time of mastectomy has not yet been proven. If this predictive capability should hold for primary tumors and eventual endocrine treatment, the ramifications are obvious: endocrine therapy could be offered to patients on a rational basis and adjuvant therapy could be considered on a plausible biochemical basis. This report details our observations as to the ER content of the primary tumor and the eventual result of endocrine therapy. Thirty-seven patients whose tumor ER was determined from the primary tumor eventually underwent some form of endocrine therapy for recurrent disease. Fifteen of the primary tumors had significant ER content and 22 possessed insignificant amounts. Only one of the 22 patients with insignificant ER content was benefited by endocrine treatment. Those patients whose tumors contained low amounts of ER experienced recurrence of their disease more rapidly than did those with higher ER content. There was no correlation of age, cell type of tumor or metastatic site with the ER content of the tumor. There is a positive correlation between response to chemotherapy and ER content of tumor. Measurement of the estrogen receptor protein content of the primary breast tumor is a reliable method for choosing patients for eventual endocrine therapy. Those patients whose tumors contain insignificant estrophilin are not candidates for such attempts at palliation.
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Neoplasias da Mama/terapia , Dietilestilbestrol/uso terapêutico , Receptores de Estrogênio/metabolismo , Adrenalectomia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Castração , Ciclofosfamida/uso terapêutico , Quimioterapia Combinada , Feminino , Fluoruracila/uso terapêutico , Seguimentos , Humanos , Metástase Linfática , Metotrexato/uso terapêutico , Metástase Neoplásica , Remissão EspontâneaRESUMO
The large-scale structure in the distribution of galaxies is thought to arise from the gravitational instability of small fluctuations in the initial density field of the Universe. A key test of this hypothesis is that forming superclusters of galaxies should generate a systematic infall of other galaxies. This would be evident in the pattern of recessional velocities, causing an anisotropy in the inferred spatial clustering of galaxies. Here we report a precise measurement of this clustering, using the redshifts of more than 141,000 galaxies from the two-degree-field (2dF) galaxy redshift survey. We determine the parameter beta = Omega0.6/b = 0.43 +/- 0.07, where Omega is the total mass-density parameter of the Universe and b is a measure of the 'bias' of the luminous galaxies in the survey. (Bias is the difference between the clustering of visible galaxies and of the total mass, most of which is dark.) Combined with the anisotropy of the cosmic microwave background, our results favour a low-density Universe with Omega approximately 0.3.
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We constrain f(nu) identical with Omega(nu)/Omega(m), the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2 Degree Field Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos, and a cosmological constant. Adding constraints from independent cosmological probes we find f(nu)<0.13 (at 95% confidence) for a prior of 0.1