Normal human cells can undergo a limited number of divisions, whereas transformed cells may have an extended life span and can give rise to immortal cells. To isolate genes involved in the immortalization process, gene expression in SV40-transformed preimmortal human fibroblasts was compared with expression in SV40-transformed immortalized fibroblasts using an mRNA differential display. We foun...

In this paper I analyze the process of formation of thin current structures in the magnetosphere of a conducting accretion disk in response to the field-line twisting brought about by the rotation of the disk relative to the central star. I consider an axisymmetric force-free magnetically-linked star–disk configuration and investigate the expansion of the poloidal field lines and partial field-...

We study the relation between size and star formation activity in a complete sample of 225 massive (M∗ > 5 · 10 M⊙) galaxies at 1.5 < z < 2.5, selected from the FIREWORKS UV-IR catalog of the CDFS. Based on stellar population synthesis model fits to the observed restframe UV-NIR SEDs, and independent MIPS 24μm observations, 65% of galaxies are actively forming stars, while 35% are quiescent. Us...

In this paper preliminary results are presented based on a study of the low and high resolution ultraviolet spectrum of the peculiar supergiant (post-AGB star) HD 101584. By a comparison of the low resolution spectrum (1200 − 3200Å) with standard stars, the star is classified as an A7I, indicating an effective temperature of 8150 K, where literature quotes spectral type F0I. The Doppler shift o...

Many early-type galaxies are detected at 24 to 160μm but the emission is usually dominated by an AGN or heating from the evolved stellar population. Here we present MIPS observations of a sample of elliptical and lenticular galaxies which are rich in cold molecular gas, and we investigate how much of the MIR to FIR emission could be due to star formation activity. The 24μm images show a rich va...

Observations to date cannot distinguish neutron stars from self-bound bare quark stars on the basis of their gross physical properties such as their masses and radii alone. However, their surface luminosity and spectral characteristics can be significantly different. Unlike a normal neutron star, a bare quark star can emit photons from its surface at super-Eddington luminosities for an extended...

The optical light curve of the Be/neutron star binary AX J0049.4−7323 has been investigated using data from the MACHO and OGLE-II projects. This X-ray source, whose neutron star has a very slow rotation rate (P pulse = 755.5 sec), shows optical outbursts every ∼394 days. The regularity of these outbursts suggests that their recurrence time is the orbital period of the system. During the outburs...

We solve an open question posed by Akers and Krishnamurthy in 1986 [1, 3] concerning VLSI layout of star graphs. We show that the area of the optimal layout of an N-node star graph, hierarchical cubic network (HCN), or hierarchical folded-hypercube network (HFN) is N2=16 o(N2) under the Thompson model, or under the extended grid model where a node occupies a rectangle of sides that may range fr...