Aspidella: un fósil de cuerpo blando ediacárico de la Arenisca de Jodhpur (Supergrupo de Marwar), área de Sursagar, Jodhpur, Rajasthan occidental, India

This paper describes well-preserved Aspidella remains, the Ediacaran body fossils from the Jodhpur Sandstone of the Marwar Supergroup in Sursagar area, Jodhpur, western Rajasthan, India. They show distinct morphological features previously described in other famous Ediacaran fossil sites, such as the Fermuse Formation of Newfoundland, South Australia and White Sea of RussiaSe describen en este trabajo los restos bien conservados de Aspidella, fósiles de cuerpo blando ediacáricos de la Arenisca de Jodhpur (Supergrupo de Marwar) el área de Sursagar, Jodhpur, al oeste de Rajasthan, India. Éstos muestran características morfológicas características descritas anteriormente en otros famosos yacimientos fósiles ediacáricos, como los de la Formación de Fermuse (Terranova), Australia meridional y el Mar Blanco de Rusia

Studies on intra-specific variations in the diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae) under different geographical regions

Studies on intraspecific variations in insect pests are an important tool for preparation of management strategy in different geographical regions. In this paper we tried to establish that these variations are also found in the diamondback moth (P. xylostella) populations under north Indian conditions with respect to reproductive biology.The pest populations were collected from five different geographical regions viz. Hisar (800feet), Kangra (2200feet), Solan (4200 feet), Theog (7500feet) and Kinnaur (9000feet) and then reared under laboratory conditions at 25±1oC on cauliflower. The life table analysis revealed that the female from the Kangra population laid maximum eggs (332.16 eggs/female) whereas the number of eggs laid by the female from the Hisar, Solan, Theog and Kinnaur population was 189.53, 207, 252 and 270 eggs/female, respectively. The doubling time (DT) was observed to be the lowest for Kangra (3.12 days) and maximum for the Hisar (4.59 days) population, whereas weekly multiplication rate was minimum for the Solan (2.252) and maximum for the kangra (4.73) population. The true generation time was the lowest for the Kangra (18.54 days) and highest for the Hisar (24.38 days) population. The true intrinsic rate of increase (rm) was found to be maximum (0.222 female progeny/female/day) for the Kangra whereas for the Kinnaur, Theog, Solan and Hisar population it was 0.203, 0.202, 0.182 and 0.151 female progeny/female/day thereby indicating that the Kangra population is more prolific as compared to the population from other geographical regions. The results are indicative of geographical variations among different populations of P. xylostella

ΔI=4\Delta I=4 and ΔI=8\Delta I=8 bifurcations in rotational bands of diatomic molecules

It is shown that the recently observed $\Delta I=4$ bifurcation seen in superdeformed nuclear bands is also occurring in rotational bands of diatomic molecules. In addition, signs of a $\Delta I=8$ bifurcation, of the same order of magnitude as the $\Delta I=4$ one, are observed both in superdeformed nuclear bands and rotational bands of diatomic molecules.Comment: LaTex twice, 10 pages and 5 PS figures provided upon demand by the Author

OPTIMIZATION AND CHARECTERIZATION OFINTRACELLULAR ORANGE FLUORESCENT PIGMENT FROM BACILLUS ENDOPHYTICUS (AVP-9(Kf527823)

Objective: Our study aimed to characterize and optimize the physico-chemical properties which render the high yield of intracellular orange fluorescent pigment (IOFP) and its antibacterial activity against clinical pathogens.Methods: Intracellular orange fluorescent pigment (IOFP) extracted from Bacillus endophyticus AVP-9(Kf527823) a rhizobacteria of chilli agricultural field using different solvent systems, fractioned by TLC and analyzed for absorption maxima. Purified pigment was screened for antimicrobial activity against clinical pathogen, Optimization of cultural conditions for maximizing the yield of pigment and compared the yield in different broth media.Results: AVP-9(Kf527823) showed circular, large orange color colonies which fluoresced orange under U. V light,. Intracellular pigment affectively extracted in acetone showed a bright fluorescent orange spot on the TLC plate, and absorption maxima at 493 nm. Antibacterial activity of isolated pigment showed highest zone of inhibition against E. coli and least to Pseudomonas. Maximum yield of the pigment was achieved in modified nutrient brot (MNB)h medium containing 2% w/v nutrient broth containing1% w/v glucose,1% w/v peptone and0.5% methionine at 35 °C and pH 7.0 with 48 h of incubation period. The yield was observed maximum in MNB. Compared to lactose broth, Tryptone soya broth and peptone water.Conclusion: Bright fluorescent orange pigment of Bacterium avp-9(Kf527823) with absorption maxima at 493 indicating that the pigment shows the characters of carotenoids. Yield maximum in MNB and its potential antibacterial activity needs further investigation for pharmaceutical applications

The combined effects of electrojet strength and the geomagnetic activity (<I>K_p</I>-index) on the post sunset height rise of the F-layer and its role in the generation of ESF during high and low solar activity periods

International audienceSeveral investigations have been carried out to identify the factors that are responsible for the day-to-day variability in the occurrence of equatorial spread-F (ESF). But the precise forecasting of ESF on a day-to-day basis is still far from reality. The nonlinear development and the sustenance of ESF/plasma bubbles is decided by the background ionospheric conditions, such as the base height of the F-layer (h'F), the electron density gradient (dN/dz), maximum ionization density (Nmax), geomagnetic activity and the neutral dynamics. There is increasing evidence in the literature during the recent past that shows a well developed Equatorial Ionization Anomaly (EIA) during the afternoon hours contributes significantly to the initiation of ESF during the post-sunset hours. Also, there exists a good correlation between the Equatorial Ionization Anomaly (EIA) and the Integrated Equatorial ElectroJet (IEEJ) strength, as the driving force for both is the same, namely, the zonal electric field at the equator. In this paper, we present a linear relationship that exists between the daytime integrated equatorial electrojet (IEEJ) strength and the maximum elevated height of the F-layer during post-sunset hours (denoted as peak h'F). An inverse relationship that exists between the 6-h average Kp-index prior to the local sunset and the peak h'F of the F-layer is also presented. A systematic study on the combined effects of the IEEJ and the average Kp-index on the post-sunset, peak height of the F-layer (peak h'F), which controls the development of ESF/plasma bubbles, is carried out using the ionosonde data from an equatorial station, Trivandrum (8.47° N, 76.91° E, dip.lat. 0.5° N), an off-equatorial station, SHAR (13.6° N, 79.8° E, dip.lat. 10.8° N) and VHF scintillations (244 MHz) observed over a nearby low-latitude station, Waltair (17.7° N, 83.3° E, dip.lat. 20° N). From this study, it has been found that the threshold base height of the F-layer at the equator for the development of plasma bubbles is reduced from 405 km to 317 km as the solar activity decreases from March 2001 (mean Rz=113.5) to March 2005 (mean Rz=24.5). This decrease in threshold height with the decreasing solar activity is explained on the basis of changes in the local linear growth rate of the collisional Rayleigh-Taylor instability, due to the variability of various terms such as inverse density gradient scale length (L?1), ion-neutral collision frequency (?in) and recombination rate (R) with the changes in the solar activity

Multiband optical monitoring of the blazars S5 0716+714 and BL Lacertae

We report results of multiband optical monitoring of two well known blazars, S5 0716+714 and BL Lacertae, carried out in 1996 and 2000-01 with an aim to study optical variations on time scales from minutes to hours and longer.The light curves were derived relative to comparison stars present on the CCD frames. Night to night flux variations of >0.1 mag were observed in S5 0716+714 during a campaign of ~2 weeks in 1996.A good correlation between the lightcurves in different optical bands was found for both inter-night and intra-night observations. Two prominent events of intra-night optical variability were detected in S5 0716+714.Each of these rapidly varying segments of the lightcurves trace an exponential flux profile whose rate of variation is the same in both cases. Our long-term monitoring data of S5 0716+714 showed a distinct flare around JD 2451875 which can be identified in the BVRI bands.This flare coincides with the brightest phase recorded during 1994-2001 in the long-term lightcurves reported by Raiteri et al.(2003). No evidence for the bluer when brighter trend was noticed on inter-night and intra-night time scales. On the other hand, our nearly simultaneous multiband observations of BL Lacertae in October 2001 showed flux variations that were not achromatic. This blazar was found to become bluer when brighter on intra-night time scales and there is a hint of the same trend on inter-night time scales. Based on five nights of observations during a week, BL Lacertae showed a peak night-to-night variability of ~0.6 mag in B. Thus, we found that the present observations of the two blazars, reveal a contrasting behaviour in terms of the dependence of spectral hardening with increasing brightness, at least on intra-night, and possibly also on inter-night, time scales.Comment: 11 pages with 10 figures,uses mn2e.cls, Accepted for publication in MNRAS. Tables 4 and 5 in full will be available in the electronic version of the articl

Searching for hexagonal analogues of the half-metallic half-Heusler XYZ compounds

The XYZ half-Heusler crystal structure can conveniently be described as a tetrahedral zinc blende YZ structure which is stuffed by a slightly ionic X species. This description is well suited to understand the electronic structure of semiconducting 8-electron compounds such as LiAlSi (formulated Li$^+$[AlSi]$^-$) or semiconducting 18-electron compounds such as TiCoSb (formulated Ti$^{4+}$[CoSb]$^{4-}$). The basis for this is that [AlSi]$^-$ (with the same electron count as Si$_2$) and [CoSb]$^{4-}$ (the same electron count as GaSb), are both structurally and electronically, zinc-blende semiconductors. The electronic structure of half-metallic ferromagnets in this structure type can then be described as semiconductors with stuffing magnetic ions which have a local moment: For example, 22 electron MnNiSb can be written Mn$^{3+}$[NiSb]$^{3-}$. The tendency in the 18 electron compound for a semiconducting gap -- believed to arise from strong covalency -- is carried over in MnNiSb to a tendency for a gap in one spin direction. Here we similarly propose the systematic examination of 18-electron hexagonal compounds for semiconducting gaps; these would be the "stuffed wurtzite" analogues of the "stuffed zinc blende" half-Heusler compounds. These semiconductors could then serve as the basis for possibly new families of half-metallic compounds, attained through appropriate replacement of non-magnetic ions by magnetic ones. These semiconductors and semimetals with tunable charge carrier concentrations could also be interesting in the context of magnetoresistive and thermoelectric materials.Comment: 11 pages, 6 figures, of which 4 are colou

Associations between prostate cancer-related anxiety and health-related quality of life

There are uncertainties about prostate cancer‐related anxiety's (PCRA) associations with health‐related quality of life (HRQOL) and major depression, and these could affect the quality of mental healthcare provided to prostate cancer patients. Addressing these uncertainties will provide more insight into PCRA and inform further research on the value of PCRA prevention. The goals of this study were to measure associations between PCRA and HRQOL at domain and subdomain levels, and to evaluate the association between PCRA and probable (ie, predicted major) depression

Distinguishing among Scalar Field Models of Dark Energy

We show that various scalar field models of dark energy predict degenerate luminosity distance history of the Universe and thus cannot be distinguished by supernovae measurements alone. In particular, models with a vanishing cosmological constant (the value of the potential at its minimum) are degenerate with models with a positive or negative cosmological constant whose magnitude can be as large as the critical density. Adding information from CMB anisotropy measurements does reduce the degeneracy somewhat but not significantly. Our results indicate that a theoretical prior on the preferred form of the potential and the field's initial conditions may allow to quantitatively estimate model parameters from data. Without such a theoretical prior only limited qualitative information on the form and parameters of the potential can be extracted even from very accurate data.Comment: 15 pages, 5 figure

A_k Generalization of the O(1) Loop Model on a Cylinder: Affine Hecke Algebra, q-KZ Equation and the Sum Rule

We study the A_k generalized model of the O(1) loop model on a cylinder. The affine Hecke algebra associated with the model is characterized by a vanishing condition, the cylindric relation. We present two representations of the algebra: the first one is the spin representation, and the other is in the vector space of states of the A_k generalized model. A state of the model is a natural generalization of a link pattern. We propose a new graphical way of dealing with the Yang-Baxter equation and $q$-symmetrizers by the use of the rhombus tiling. The relation between two representations and the meaning of the cylindric relations are clarified. The sum rule for this model is obtained by solving the q-KZ equation at the Razumov-Stroganov point.Comment: 43 pages, 22 figures, LaTeX, (ver 2) Introduction rewritten and Section 4.3 adde