The Nova-like Variables

We review optical observations and theoretical models of the non-magnetic nova-like variables (UX UMa, VY Scl and SW Sex stars). A brief discussion of the classification scheme is followed by a statistical overview of the observed properties. The most important features of each of the sub-classes are then reviewed, concluding with a summary of the theoretical models invoked to understand these systems.Comment: 10 pages, 5 figures; published in Cataclysmic Variables and Related Objects, Proceedings of the 158th colloquium of the IAU held at Keele, edited by A. Evans and Janet H. Wood, p.3 (1996

Growth and Prospects of Agro-Processing Industries in Punjab

Present study attempts to examine the growth and prospects of agro-processing industries in Punjab in the post liberalization period. Punjab that used to perform reasonably well in terms of industrialization, few years back, is today facing the industrial crunch owing to obvious reasons. Keeping present trends in mind, the state needs to emulate the growth path adopted by China, explicitly, wherein thrust to development had been on the manufacturing sector. With availability of food grain production round the year, it seems viable also in the state to develop the agro processing industries. In fact, researchers have pointed out that Punjab’s agriculture has reached a stage where its sustainability is in doubt. If such apprehensions turn out to be true, then future of masses will also land in darkness. Development of agro-processing industries at this juncture, are perceived to be the stimulator that can revamp the vanished glory of the state. The study is an attempt made through empirical framework to find out the conditions for the development of agro-processing industries in the state.Keywords. Prospects, Agro-processing, Development.JEL. L52, L66, L67

A Self-Occulting Accretion Disk in the SW Sex Star DW UMa

We present the ultraviolet spectrum of the SW Sex star and nova-like variable DW UMa in an optical low state, as observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope (HST). The data are well described by a synthetic white dwarf (WD) spectrum with T_eff = 46,000 +/- 1000 K, log g = 7.60 +/- 0.15, v*sin(i) = 370 +/- 100 km/s and Z/Z_solar = 0.47 +/- 0.15. For this combination of T_eff and log g, WD models predict M_WD = 0.48 +/- 0.06 M_solar and R_WD = (1.27 +/- 0.18) * 10^9 cm. Combining the radius estimate with the normalization of the spectral fit, we obtain a distance estimate of d = 830 +/-150 pc. During our observations, DW UMa was approximately 3 magnitudes fainter in V than in the high state. A comparison of our low-state HST spectrum to a high-state spectrum obtained with the International Ultraviolet Explorer shows that the former is much bluer and has a higher continuum level shortward of 1450 A. Since DW UMa is an eclipsing system, this suggests that an optically thick accretion disk rim blocks our view of the WD primary in the high state. If self-occulting accretion disks are common among the SW Sex stars, we can account for (i) the preference for high-inclination systems within the class and (ii) their V-shaped continuum eclipses. Moreover, even though the emission lines produced by a self-obscured disk are generally still double-peaked, they are weaker and narrower than those produced by an unobscured disk. This may allow a secondary line emission mechanism to dominate and produce the single-peaked, optical lines that are a distinguishing characteristic of the SW Sex stars.Comment: 9 pages, including 2 figures; accepted for publication in Astrophysical Journal Letters; New version matches version in press (footnote added to discussion section; figures now use color