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Information regarding the frictional characteristics of rubber on ice surfaces is helpful in the study of skid behaviour of vehicles on icy roads. This paper describes an experimental test rig developed to study the frictional characteristics of rubber on ice surfaces under controlled conditions in a laboratory. The effect of various operating parameters such as load, speed, temperature, type of ice surface, etc., have been studied and the results discussed.

The inflorescence ofDichrostachys cinerea is described in detail. In addition to the two externally well-marked zones consisting of the upper perfect and bisexual flowers, and the lower sterile ones, there is a short intermediate zone of a few flowers which form a transition between the two. Sterilization of the inflorescence is basipetal; of the flower centripetal.

Nondimensional parameters characteristic of the outer part of the planetary boundary layer have been determined by fitting a simple, Ekman-type theory to a number of averaged, observed velocity distributions, using the Wangara data of Clarke et al. (1971). The theoretical model is based on constant eddy viscosity in the outer layer and a linear variation of the geostrophic wind with height. At the lower boundary of the outer layer, the condition is applied that stress and velocity are parallel. This yields an equation for the cross-isobar angle as a function of drag coefficient, depth coefficient and nondimensional thermal wind. The data could be sorted into three well-defined, distinct groups, each characterized by a more or less constant value of the depth coefficient. The group with the lowest value of this parameter contains most of the nighttime data, the middle group the remaining nighttime data and most of the daytime ones, and the group with the largest depth, daytime data with cold air advection. The difference between the lowest and highest depth coefficients found here is about a factor of three. Within each group separately, the theoretically derived cross-isobar angle agrees remarkably well with the observed one, as a function of thermal wind.

IEMIZONIA IS A genus of the tribe Madiinae of the family Compositae. Commonly known as the tarweeds, its members are confined in their distribution largely to California including the coastal islands, and partly to adjacent Oregon, Nevada and Baja California. As reconstituted by Keck (unpublished) the genus consists of four sections: Zonamra, Deinandra, Centromadia and Hemizonia. In the earlier taxonomic treatment of Jepson (1925), the spikeweeds, Centromadia, were accorded generic status. Keck (1935) recognized four species under Centromadia: Hemnizonia pungens (Hk. et Arn.) Torr. et Gray, H. parryi Greene, H. fitchii Gray and H. perennis (Greene) Keck. Characters of the pappus, anthers, bracts, inflorescence and herbage are used to distinguish the taxa. Hemizonia pungens has no pappus on its disk florets, H. parryi has three pappus bristles per disk floret and H. fitchii has many. The chromosome ntumbers previousl y recorded are n 9 for H. pungens, n 11 and 12 for H. parryi and n 13 for H. fitchii (Clausen, Keck and Heusi, 1934). The chromosome number of H. perennis is unknown; unlike the other species, it is a perennial and is known from only two localities in Baja California. Figure 1 shows the relative distribution of the species and subspecies. Hemizonia pungens, by far the commonest member of the section, is widely distributed. At least in California, there are three distinct forms of this species which occur in more or less distinct ecological niches and are taxonomically treated as subspecies. The maritime form, H. pungens ssp. mnaritima Keck occurs chiefly in salt marshes around San Francisco bay and along the coast, but is rare elsewhere. Hemizonia pungens ssp. interior Keck, an inland form occurring in the dry inner valleys, is very abundant throughout the San Joaquin and Salinas valleys and probably has been introduced along the western borders of the Mojave desert. The populations occurring in the passes of the Inner Coast Range which separates the two subspecies, contain many intermediates and recombinations. Hemizonia pungens ssp. laevis is

A study of the essential features of piston rings in the cylinder liner of an internal combustion engine reveals that the lubrication problem posed by it is basically that of a slider bearing. According to steady-flow-hydrodynamics, viz. Image the oil film thickness becomes zero at the dead centre positions as the velocity, U = 0. In practice, however, such a phenomenon cannot be supported by consideration of the wear rates of pistion rings and cylinder liners. This can be explained by including the “squeeze” action term in the

This paper explores the pertinent challenges of Government’s HIV/AIDS prevention, care and treatment program in India. Study is mainly based on observations made during field visits, discussion during review meetings at various levels and during training programmes of various functionaries from April 2007-November 2009. The paper also takes into account the observations made on the conclusion of the Mid-term Review conducted by the Government of India in during July- December 2009 after completion of first 2.5 years of the 5-year plan of NACP-III. Additionally, interactions with key program managers involved in implementation and management of HIV/AIDS Program at the state, district and facility levels. Though numerous efforts have been made and continued by the Government and partners, HIV prevention, care and treatment services have not been able to reach to the most-at-risk population, specifically in the rural population. Socio-cultural and managerial issues are the key challenges reported by the most of the key implementers. There is an urgent need to address and strengthen the whole spectrum of health systems through a collaborative approach to achieve the millennium development goals of universal access to prevention, care and treatment services in India. DOI: 10.3126/saarctb.v7i1.3955SAARC J. TUBER. LUNG DIS. HIV/AIDS 2010 VII(1) 1-7

The detergent quality of the crankcase oil of an I.C. Engine is evaluated by studying the deposits on the piston surface after a test run. The usual method of recording the appearance, texture and location of these deposits is by photography. However, photographing a mere elevation of the piston surface from different angles is not satisfactory. A developed view of the entire piston surface is essential to have a correct idea about the deposits.

available for study. The gross features of the anthers were observed in whole mounts cleared in lactophenol. The structural details were investigated from microtome sections of material imbedded in paraffin and cut at thicknesses ranging from 8-12,u. The sections were stained with Heidenhain's iron-alumhaematoxylin followed by eosin. OBSERVATIONS The large showy flowers contain numerous hypogynous stamens with long and slender filaments. The anthers are dithecous (figs. 1-3) but each of the two thecae is curved like a horse-shoe, whose dorsal arm (d) facing the periphery of the flower, is longer than the ventral (v) facinfg the centre of the flower. As a result of such curvature, the morphological base (b) and apex (a) of the anther are brought close together (fig. 2). The filament is fixed on the shorter side, which is the real base of the anther. The vascular bundle of the filament continues in the anther to form a loop (vl) which extends close to the apex (fig. 3). ABBREVIATIONS