Quaternion Analysis for Generalized Electromagnetic Fields of Dyons in Isotropic Medium

Quaternion analysis of time dependent Maxwell's equations in presence of electric and magnetic charges has been developed and the solutions for the classical problem of moving charges (electric and magnetic) are obtained in unique, simple and consistent manner

Population dynamics of potential bioagents of mustard aphid, Lipaphiserysimi(Kaltenbach) on different cultivars of rapeseed-mustard

Field experiment was conducted to study the population dynamics of potential bioagents of mustard aphids on 9 different cultivars which included: Brassica alba cv. PSB-I, Eruca sativa Mill cv. T-27, Brassica campestriscv. BSH-I, Brassica napuscv. Sheetal, B. carinataBraun cv. CCN-06- 1, B. junceaL. cv. Varuna, B. nigraKoch. cv. PBR-I, Brassica campestriscv.YST-151 and Brassica campestriscv. PT-30. Population of aphid and natural enemies was recorded at weekly intervals. The results indicated that the first appearance of coccinellids and syrphids has been observed during 4th standard week, which gradually build up population and attained peak during 9th (pooled mean 1.42 coccinellids/ plant and 0.122 syrphid larva/plant) and 8th standard week (pooled mean 3.96 coccinellids/plant and 0.228 syrphid larva/plant) in 2008-09 and 2009-10 respectively, followed by a declining trend in the following weeks. Similarly first appearance of parasi-tization has been found to occur from 4th standard week followed by a gradual increase in the following weeks with maximum parasitization on PT-30 (33.32%) and BSH-1 (35.25%) during 2008-09 and 2009-10 respectively. Correlation between abiotic factors and these natural enemies was also studied. It has been observed that with the increase of aphid population the population of natural enemies also increased. The population dynamics of mustard aphids and its natural enemies var-ied according to climatic situations and between host plant species. So by computing population trends of both natu-ral enemies and aphids with meterological records would generate information on relative abundance and would certainly help in formulating sound pest management strategies against mustard aphid

Observations of Multiple Surges Associated with Magnetic Activities in AR10484 on 25 October 2003

We present a multiwavelength study of recurrent surges observed in H{\alpha}, UV (SOHO/EIT) and Radio (Learmonth, Australia) from the super-active region NOAA 10484 on 25 October, 2003. Several bright structures visible in H{\alpha} and UV corresponding to subflares are also observed at the base of each surge. Type III bursts are triggered and RHESSI X-ray sources are evident with surge activity. The major surge consists of the bunches of ejective paths forming a fan-shape region with an angular size of (\approx 65\degree) during its maximum phase. The ejection speed reaches upto \sim200 km/s. The SOHO/MDI magnetograms reveal that a large dipole emerges east side of the active region on 18-20 October 2003, a few days before the surges. On October 25, 2003, the major sunspots were surrounded by "moat regions" with moving magnetic features (MMFs). Parasitic fragmented positive polarities were pushed by the ambient dispersion motion of the MMFs and annihilated with negative polarities at the borders of the moat region of the following spot to produce flares and surges. A topology analysis of the global Sun using PFSS shows that the fan structures visible in the EIT 171 A images follow magnetic field lines connecting the present AR to a preceding AR in the South East. Radio observations of type III bursts indicate that they are coincident with the surges, suggesting that magnetic reconnection is the driver mechanism. The magnetic energy released by reconnection is transformed into plasma heating and provides the kinetic energy for the ejections. A lack of a radio signature in the high corona suggests that the surges are confined to follow the closed field lines in the fans. We conclude that these cool surges may have some local heating effects in the closed loops, but probably play a minor role in global coronal heating and the surge material does not escape to the solar wind.Comment: Accepted for the Publication in ApJ; 25 pages, 10 Figures, and 1 Tabl

Biology and feeding potential of Coccinella septempunctata (Linn.) against Lipaphis erysimi (Kalt) at different temperature regimes

Biology and feeding potential of Coccinella septempunctata (Linn.) were studied in laboratory on 3rd instar nymphs of mustard aphid (Lipaphis erysimi Kalt.) at two different temperature regimes. At 30± 20C, fecundity, oviposition period, hatchability of eggs, male and female longevity (232±70.46, 12.8±3.91, 82.87±6.66, 22.70 ± 2.21and 26.60 ± 4.45, respectively) were higher and incubation period, pre-oviposition period, total grub duration and pupal duration (2.6±0.51, 6.5±3.53, 8.7 ± 1.63 and 5.1 ± 1.10, respectively) were lesser in comparison to 25± 20C where fecundity, oviposition period, hatchability of eggs, male and female longevity, incubation period, preoviposition period, total grub duration and pupal duration were 169.8±61.12, 7.9±1.37, 71.68±4.08, 16.2 ± 1.31 and 21.50 ± 1.95, 2.9±0.73, 7.7±2.49, 11.1 ± 1.52 and 5.8 ± 0.918, respectively . At 27± 2 0C, total mustard aphid consumption by a grub of C. septempunctata during the whole life span, was 424.4±2.78 mustard aphids in comparison to 272.64±1.79 mustard aphid at 23± 20C. Similarly an adult male and female consumed 103.2±1.52 and 116.6 ±1.46 aphids per day respectively at 27± 2 0C in comparison to 65.6 ± 1.02 and 71.8 ± 1.60 at 23± 20C. Thus, at both temperatures aphid consumption increased gradually till 4th instar and 30±20C was found to be most suitable temperature as compared to 25±20C for the life history of C. septempunctata. Hence, it could be concluded that C. septempunctata might play a suitable role in biointensive Integrated Pest Management programme because of better longevity and high predatory potential against the mustard aphid

Far-infrared observations of Circinus and NGC 4945 galaxies

Circinus and NGC 4945 are two galaxies luminous in the infrared and are characterized by compact non thermal radio nuclei, deep silicate absorption features and unusually strong water vapor maser luminosities. Moorwood and Glass (1984) have observed these galaxies extensively in the 1 to 20 micron range. In the far-infrared, observations up to 100 microns are available from the Infrared Astronomy Satellite (IRAS). In order to study the cool dust component of these galaxies, researchers observed them at 150 microns using the Tata Institute of Fundamental Research (TIFR) 100 cm balloon-borne telescope. Here, they report observations along with deconvolved maps at 50 and 100 microns obtained from the Chopped Photometric Channel (CPC) on board IRAS

Efficient absolute aspect determination of a balloon borne far infrared telescope using a solid state optical photometer

The observational and operational efficiency of the TIFR 1 meter balloon borne far infrared telescope has been improved by incorporating a multielement solid state optical photometer (SSOP) at the Cassegrain focus of the telescope. The SSOP is based on a 1-D linear photo diode array (PDA). The online and offline processing schemes of the PDA signals which have been developed, lead to improvement in the determination of absolute telescope aspect ($\sim$ 0\farcm8), which is very crucial for carrying out the observations as well as offline analysis. The SSOP and its performance during a recent balloon flight are presented here.Comment: To appear in the February 2000 issue of the PAS

Spectroscopic Techniques and Their Application in Metabolic Profiling of Wood: A Minireview

GC/LC-MS and NMR spectroscopy have increasingly occupied a central position in the methodologies developed for metabolic analysis. This brief review deals with introduction of terminology used in metabolic analysis. Gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (NMR) commonly used in metabolic analysis and metabolic profiling of wood and wood based material by spectroscopic techniques. Apart from the description of the different methods, this review will try to direct the reader to the main approaches for analysis of metabolites in wood science. Keywords: Metabolic profiling, Wood, GC/LC-MS, NMR Spectroscopy

Mass function and dynamical study of the open clusters Berkeley 24 and Czernik 27

We present a $UBVI$ photometric study of the open clusters Berkeley 24 (Be 24) and Czernik 27 (Cz 27). The radii of the clusters are determined as 2\farcm7 and 2\farcm3 for Be 24 and Cz 27, respectively. We use the Gaia Data Release 2 (GDR2) catalogue to estimate the mean proper motions for the clusters. We found the mean proper motion of Be 24 as $0.35\pm0.06$ mas yr$^{-1}$ and $1.20\pm0.08$ mas yr$^{-1}$ in right ascension and declination for Be 24 and $-0.52\pm0.05$ mas yr$^{-1}$ and $-1.30\pm0.05$ mas yr$^{-1}$ for Cz 27. We used probable cluster members selected from proper motion data for the estimation of fundamental parameters. We infer reddenings $E(B-V)$ = $0.45\pm0.05$ mag and $0.15\pm0.05$ mag for the two clusters. Analysis of extinction curves towards the two clusters show that both have normal interstellar extinction laws in the optical as well as in the near-IR band. From the ultraviolet excess measurement, we derive metallicities of [Fe/H]= $-0.025\pm0.01$ dex and $-0.042\pm0.01$ dex for the clusters Be 24 and Cz 27, respectively. The distances, as determined from main sequence fitting, are $4.4\pm0.5$ kpc and $5.6\pm0.2$ kpc. The comparison of observed CMDs with $Z=0.01$ isochrones, leads to an age of $2.0\pm0.2$ Gyr and $0.6\pm0.1$ Gyr for Be 24 and Cz 27, respectively. In addition to this, we have also studied the mass function and dynamical state of these two clusters for the first time using probable cluster members. The mass function is derived after including the corrections for data incompleteness and field star contamination. Our analysis shows that both clusters are now dynamically relaxedComment: 16 pages including 8 tables. 22 figures. Accepted by MNRA

Generalized Gravi-Electromagnetism

A self consistant and manifestly covariant theory for the dynamics of four charges (masses) (namely electric, magnetic, gravitational, Heavisidian) has been developed in simple, compact and consistent manner. Starting with an invariant Lagrangian density and its quaternionic representation, we have obtained the consistent field equation for the dynamics of four charges. It has been shown that the present reformulation reproduces the dynamics of individual charges (masses) in the absence of other charge (masses) as well as the generalized theory of dyons (gravito - dyons) in the absence gravito - dyons (dyons). key words: dyons, gravito - dyons, quaternion PACS NO: 14.80H