Recent Results from CARMA

The Combined Array for Research in Millimeter-wave Astronomy (CARMA) is a heterogeneous array of 23 telescopes designed to operate in the 1 cm, 3 mm, and 1 mm atmospheric windows. The array is a merger of the eight 3.5 m antennas from the Sunyaev-Zel’dovich Array, the nine 6.1 m antennas from the Berkeley-Illinois-Maryland array, and the six 10.4 m antennas from the Owens Valley Radio Observatory (OVRO). As a signature of Tom Phillips’ legacy, three of the CARMA antennas are from the original 3-element OVRO interferometer built under Tom’s leadership in the early 1980’s. Recent CARMA results are presented on the structure of circumstellar disks and the molecular gas distribution in M 51

Magnetic ground state of pyrochlore oxides close to metal-insulator boundary probed by muon spin rotation

Magnetism of ruthernium pyrochlore oxides A2Ru2O7 (A = Hg, Cd, Ca), whose electronic properties within a localized ion picture are characterized by non-degenerate t2g orbitals (Ru5+, 4d3) and thereby subject to geometrical frustration, has been investigated by muon spin rotation/relaxation (muSR) technique. The A cation (mostly divalent) was varied to examine the effect of covalency (Hg > Cd > Ca) on their electronic property. In a sample with A = Hg that exhibits a clear metal-insulator (MI) transition below >> 100 K (which is associated with a weak structural transition), a nearly commensurate magnetic order is observed to develop in accordance with the MI transition. Meanwhile, in the case of A = Cd where the MI transition is suppressed to the level of small anomaly in the resistivity, the local field distribution probed by muon indicates emergence of a certain magnetic inhomogeneity below {\guillemotright} 30 K. Moreover, in Ca2Ru2O7 that remains metallic, we find a highly inhomogeneous local magnetism below >>25 K that comes from randomly oriented Ru moments and thus described as a "frozen spin liquid" state. The systematic trend of increasing randomness and itinerant character with decreasing covalency suggests close relationship between these two characters. As a reference for the effect of orbital degeneracy and associated Jahn-Teller instability, we examine a tetravalent ruthernium pyrochlore, Tl2Ru2O7 (Ru4+, 4d4), where the result of muSR indicates a non-magnetic ground state that is consistent with the formation of the Haldane chains suggested by neutron diffraction experiment.Comment: 12 pages, 13 figure

Expression of the apoptotic markers in normal breast epithelium, benign mammary dysplasia and in breast cancer

Apoptosis and proliferation are processes associated with the development and progression of breast cancer. The sensitivity of tumour cells to the induction of apoptosis depends on the balance between pro- and anti-apoptotic proteins. The expression of Bak and Bcl-2 was examined using an immunohistochemical method in 71 primary breast cancers. Furthermore, Bcl-2 and Bak were assessed in the normal mammary gland as well as in benign mammary dysplasia adjacent to breast cancer. Positive immunostaining for Bcl-2 was observed in 77.8% of cases of normal breast epithelium (NBE), 93% of benign dysplasia without intraductal proliferation (BBD) as well as in 94% of intraductal proliferative lesions of the breast (BIPL). Expression of Bak was detected in 39% of cases of NBE, 45% of BBD and in 67% of BIPL. In breast cancer Bcl-2 and Bak expression was found in 83% and 70% of the cases studied, respectively. Increased Bcl-2 expression in primary tumours significantly correlated with favourable prognostic factors, namely pT1, G2 and lack of metastases to the regional lymph nodes (p < 0.01, p < 0.03, p < 0.02, respectively). There were no relationships between Bak and the clinicopathological features studied, but our results indicate changes in the expression of Bak during breast cancer development and progression. It would appear to be important to assess and compare pro- and anti-apoptotic proteins between normal mammary gland, benign mammary dysplasia and the primary tumours of breast cancer. This knowledge should be helpful in understanding breast cancer development and progression

Equation of State for Parallel Rigid Spherocylinders

The pair distribution function of monodisperse rigid spherocylinders is calculated by Shinomoto's method, which was originally proposed for hard spheres. The equation of state is derived by two different routes: Shinomoto's original route, in which a hard wall is introduced to estimate the pressure exerted on it, and the virial route. The pressure from Shinomoto's original route is valid only when the length-to-width ratio is less than or equal to 0.25 (i.e., when the spherocylinders are nearly spherical). The virial equation of state is shown to agree very well with the results of numerical simulations of spherocylinders with length-to-width ratio greater than or equal to 2