Root sclereids ofSyzygium cumini (L.) Skeels

Sclereids in the roots ofSyzygium cumini (L.) Skeels (Myrtaceae) are polymorphic. In addition to the brachy-, osteo- and bizarre sclereids, there occur an interesting kind of sclereids—the fibre sclereids—resembling the fibres in some respects. Sclereids appear only after the onset of secondary activity and fall into one of the following categories depending on their origin: (a) a continuous strand of sclereids in the secondary cortex. This develops from parenchymatous initials that are derivatives of phellogen. Fibre sclereids occur only in this region along with ordinary sclereids and a few fibres. (b) sclereids formed through secondary sclerosis of distal mature parenchyma cells of the dilating phloem rays. (c) Sclereids formed through secondary sclerosis of mature parenchyma cells in old phloem. Sclereids of categoriesb andc a but on those ofa forming a composite strand. All the kinds of sclereids here possess thick, highly lamellated lignified walls with simple and wide pit canals ending in round or oval apertures. The adult sclereids are devoid of nuclei, starch or crystals. Insoluble tannin is present in them except in those formed from phloem parenchyma. Ontogenetical stages of the various kinds of sclereids are similar except that fibre sclereids show a pronounced intrusive growth which although initially bipolar later becomes unipolar. Other kinds of sclereids show either a purely symplastic growth or a combination of various degrees of symplastic and intrusive growth which is either diffuse (some osteosclereids) or multipolar (bizarre sclereids). The inadequacy and unreliability of the existing classifications of and criteria for classifying different mechanical elements particularly in sclereid containing plants are discussed and suggestions made

X-Ray Bursts from the Galactic X-Ray Transient Source GRS 1915+105

We have analyzed publicly available RXTE/PCAs archival data of GRS 1915+105 during its burst/flaring state. The burst cycle ranges from 30 to 1300 s. These bursts are different from the type I and type II classical bursts seen in Low Mass X-ray Binaries (LMXBs) in terms of their temporal and spectral properties. We have classified these bursts on the basis of properties observed during the quiescent (low flux) phase. The 2 - 10 Hz QPOs are present during the quiescent phase and disappear during the burst phase of all types of these X-ray bursts. The duration of the quiescent phase can be explained assuming an outflow from the post-shock regions and the catastrophic Compton cooling.Comment: 5 pages with two figures, 33rd COSPAR, Warsaw, Poland, July 16-22, 200

X-ray variability of GRS 1915+105 during the low-hard state observed with the Indian X-ray astronomy experiment (IXAE)

The galactic superluminal transient X-ray source GRS 1915+105 was observed with the pointed proportional counters (PPCs) onboard the Indian satellite IRS-P3 during 1996 July 23-27. We report here details of the behavior of this source during the relatively quiet and low luminosity state. Large intensity variations by a factor of 2 to 3, generally seen in black-hole candidates, are observed at a time scale of 100 ms to few seconds. No significant variation is detected over larger time scale of minute or more. The intensity variations are described as sum of shots in the light curve, and the number distribution of the shots are found to be exponential function of the fluence and duration of the shots. The cross correlation spectrum between 6-18 keV and 2-6 keV X-rays is found to have asymmetry signifying a delay of the hard X-rays by about 0.2 to 0.4 sec. This supports the idea of hard X-rays being generated by Compton up-scattering from high energy clouds near the source of soft X-rays. Very strong and narrow quasi periodic oscillations in the frequency range 0.62 to 0.82 Hz are observed. We discuss about a model which explains a gradual change in the QPO frequencies with corresponding changes in the mass accretion rate of the disk.Comment: 14 pages including 6 figures. To appear in Astronomy and Astrophysics Supplement Serie

Response of wheat cultivars to foliar potassium fertilization under irrigated saline environment

A field experiment with split-split plot design (SSPD) was conducted to study the response of two winter wheat (Triticumaestivum L.) cultivars (viz. salt tolerant cultivar KRL-1-4 and salt non-tolerant cultivar HD-2894) under saline irrigation regimes with and without foliar potassium fertilization on growth and grain yield of wheat during rabi 2011-12 and 2012-13. Potassium in the ratio of K+: Na+ (1: 10) was applied as foliar application during the heading stage of the crop. Results showed that the grain yield of KRL-1-4 and HD-2894 cultivars with foliar potassium fertilization at the heading stage increased by 6.5 to 22% and 3 to 15% during rabi 2011-2012, respectively under different saline irrigation regimes as compared to the control. Moreover, the results of rabi 2012-13 showed an increase in grain yield ranging from 4.5 to 20% for KRL-1-4 as compared to the control. Statistical analysis of grain yield parameter showed that the foliar potassium application in both varieties resulted in significant yield difference at 0.05 probability level as compared to the non-foliar application. Overall, it was observed that the foliar potassium fertilization increased the grain yield of both wheat cultivars, while the salt tolerant cultivar performed better than the salt non-tolerant cultivar under irrigated saline regimes

Werner states and the two-spinors Heisenberg anti-ferromagnet

We ascertain, following ideas of Arnesen, Bose, and Vedral concerning thermal entanglement [Phys. Rev. Lett. {\bf 87} (2001) 017901] and using the statistical tool called {\it entropic non-triviality} [Lamberti, Martin, Plastino, and Rosso, Physica A {\bf 334} (2004) 119], that there is a one to one correspondence between (i) the mixing coefficient $x$ of a Werner state, on the one hand, and (ii) the temperature $T$ of the one-dimensional Heisenberg two-spin chain with a magnetic field $B$ along the $z-$axis, on the other one. This is true for each value of $B$ below a certain critical value $B_c$. The pertinent mapping depends on the particular $B-$value one selects within such a range

Primary double tooth with partial anodontia of permanent dentition: a case report

Dental anomalies of number and forms may occur in the primary and permanent dentition. Various terms have been used to describe dental twinning anomalies: gemination, fusion, concrescence, double teeth, cojoined teeth, twinned teeth, geminifusion and vicinifusion. Double tooth is a term used to describe connate tooth and includes both dental fusion and gemination. The phenomenon of gemination occurs when two teeth develop from one single bud leading to a larger tooth. Fusion is a condition in which the crowns of two separate teeth have been joined toge- ther during the crown development. Fusion occurs infrequently but could cause esthetic, spacing and periodontal problems. The present article highlights the presence of a primary double tooth in an 11 year old boy involving primary mandibular left lateral incisor and canine. Clinical examination and radiographic examination confirmed the absence of the permanent left mandibular lateral incisor. Cases with primary double tooth necessitate careful examination as they may be associated with anomalies in the succeeding permanent dentition and require proper treatment plannin

Fast Transition between High-soft and Low-soft States in GRS 1915+105: Evidence for a Critically Viscous Accretion Flow

We present the results of a detailed analysis of RXTE observations of class $\omega$ which show an unusual state transition between high-soft and low-soft states in the microquasar GRS 1915+105. Out of about 600 pointed RXTE observations, the source was found to exhibit such state transition only on 16 occasions. An examination of the RXTE/ASM data in conjunction with the pointed observations reveals that these events appeared as a series of quasi-regular dips in two stretches of long duration (about 20 days during each occasions) when hard X-ray and radio flux were very low. The X-ray light curve and color-color diagram of the source during these observations are found to be different from any reported so far. The duration of these dips is found to be of the order of a few tens of seconds with a repetition time of a few hundred seconds. The transition between these dips and non-dips which differ in intensity by a factor of ~ 3.5, is observed to be very fast (~ a few seconds). It is observed that the low-frequency narrow QPOs are absent in the power density spectrum (PDS) of the dip and non-dip regions of class $\omega$ and the PDS is a power law in 0.1 - 10 Hz frequency range. There is a remarkable similarity in the spectral and timing properties of the source during the dip and non-dip regions in these set of observations. These properties of the source are distinctly different from those seen in the observations of other classes. This indicates that the basic accretion disk structure during both dip and non-dip regions of class $\omega$ is similar, but differ only in intensity. To explain these observations, we invoke a model in which the viscosity is very close to critical viscosity and the shock wave is weak or absent.Comment: Replaced with correct figures, Jour. of Astrophysics and Astronomy (accepted

A thermodynamic framework to develop rate-type models for fluids without instantaneous elasticity

In this paper, we apply the thermodynamic framework recently put into place by Rajagopal and co-workers, to develop rate-type models for viscoelastic fluids which do not possess instantaneous elasticity. To illustrate the capabilities of such models we make a specific choice for the specific Helmholtz potential and the rate of dissipation and consider the creep and stress relaxation response associated with the model. Given specific forms for the Helmholtz potential and the rate of dissipation, the rate of dissipation is maximized with the constraint that the difference between the stress power and the rate of change of Helmholtz potential is equal to the rate of dissipation and any other constraint that may be applicable such as incompressibility. We show that the model that is developed exhibits fluid-like characteristics and is incapable of instantaneous elastic response. It also includes Maxwell-like and Kelvin-Voigt-like viscoelastic materials (when certain material moduli take special values).Comment: 18 pages, 5 figure

Sedimentation record in the Konkan-Kerala Basin: implications for the evolution of the Western Ghats and the Western Indian passive margin

The Konkan and Kerala Basins constitute a major depocentre for sediment from the onshore hinterland of Western India and as such provide a valuable record of the timing and magnitude of Cenozoic denudation along the continental margin. This paper presents an analysis of sedimentation in the Konkan-Kerala Basin, coupledwith a mass balance study, and numerical modelling of flexural responses to onshore denudational unloading and o¡shore sediment loading in order to test competing conceptual models for the development of high-elevation passive margins. The Konkan-Kerala Basin contains an estimated 109,000 km<sup>3</sup>; of Cenozoic clastic sediment, a volume difficult to reconcile with the denudation of a downwarped rift flank onshore, and more consistent with denudation of an elevated rift flank. We infer from modelling of the isostatic response of the lithosphere to sediment loading offshore and denudation onshore that flexure is an important component in the development of the Western Indian Margin.There is evidence for two major pulses in sedimentation: an early phase in the Palaeocene, and a second beginning in the Pliocene. The Palaeocene increase in sedimentation can be interpreted in terms of a denudational response to the rifting between India and the Seychelles, whereas the mechanism responsible for the Pliocene pulse is more enigmatic

The WATCH All-Sky Monitor for the Granat Project

Watch is an X-ray all-sky monitor capable of localizing strong X-ray sources and following their time development. The GRANAT satellite, to be launched in 1989, carries several large X- and gamma-ray telescopes and gamma-burst detector arrays