1,306 research outputs found

    Field Screening of Lentil Genotypes Against Aphid Infestation in Inner Tarai of Nepal

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    Twenty lentil (Lens culinaris Medik) genotypes received from Grain Legumes Research Program, Khajura, Banke were screened for relative tolerance against aphid (Aphis craccivora Koch.) at the research field of National Maize Research Program, Rampur, Chitwan during winter seasons of two consecutive years 2016 and 2017. The design of the experiment was Randomized Complete Block having three replications. The unit plot size was 4m × 1 m with 25cm row to row spacing and continue plant to plant spacing was maintained and net harvested plot was 4 square meters. The recommended dose of fertilizer was 20:40:20 N:P2O5:K2O kg/ha and seed rate 30 kg/ha. Insect data were collected based on aphid population found at apical twigs (10 cm) per plant and scoring was done during flowering and pod formation stage. The grain yield was recorded. All screened genotypes differed significantly (p<0.05) on aphid population and grain yield.  Genotypes, ILL 9924, RL 83, ILL 10856, ILL 6458 and RL 67 were less susceptible with higher grain yield. These results have important implications for the development of aphid tolerant high yielding lentil variety in inner Tarai of Nepal

    Reconstructing a model of quintessential inflation

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    We present an explicit cosmological model where inflation and dark energy both could arise from the dynamics of the same scalar field. We present our discussion in the framework where the inflaton field ϕ\phi attains a nearly constant velocity mP1dϕ/dNα+βexp(βN)m_P^{-1} |d\phi/dN|\equiv \alpha+\beta \exp(\beta N) (where NlnaN\equiv \ln a is the e-folding time) during inflation. We show that the model with α<0.25|\alpha|<0.25 and β<0\beta<0 can easily satisfy inflationary constraints, including the spectral index of scalar fluctuations (ns=0.96±0.013n_s=0.96\pm 0.013), tensor-to-scalar ratio (r<0.28r<0.28) and also the bound imposed on Ωϕ\Omega_\phi during the nucleosynthesis epoch (Ωϕ(1MeV)<0.1\Omega_\phi (1 {\rm MeV})<0.1). In our construction, the scalar field potential always scales proportionally to the square of the Hubble expansion rate. One may thereby account for the two vastly different energy scales associated with the Hubble parameters at early and late epochs. The inflaton energy could also produce an observationally significant effective dark energy at a late epoch without violating local gravity tests.Comment: 18 pages, 7 figures; added refs, published versio

    Warped compactification on curved manifolds

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    The characterization of a six- (or seven)-dimensional internal manifold with metric as having positive, zero or negative curvature is expected to be an important aspect of warped compactifications in supergravity. In this context, Douglas and Kallosh recently pointed out that a compact internal space with negative curvature could help to construct four-dimensional de Sitter solutions only if the extra dimensions are strongly warped or there are large stringy corrections. That is, the problem of finding 4-dimensional de Sitter solutions is well posed, if all extra dimensions are physically compact, which is called a no-go theorem. Here, we show that the above conclusion does not extend to a general class of warped compactifications in classical supergravity that allow a non-compact direction or cosmological solutions for which the internal space is asymptotic to a cone over a product of compact Einstein spaces or spheres. For clarity, we present classical solutions that compactify higher-dimensional spacetime to produce a Robertson--Walker universe with de Sitter-type expansion plus one extra non-compact direction. Such models are found to admit both an effective four-dimensional Newton constant that remains finite and a normalizable zero-mode graviton wavefunction. We also exhibit the possibility of obtaining 4D de Sitter solutions by including the effect of fluxes (p-form field strengths).Comment: 24 pages, 1 figure; v5 significant changes in the presentation, published (journal) versio

    Completely localized gravity with higher curvature terms

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    In the intersecting braneworld models, higher curvature corrections to the Einstein action are necessary to provide a non-trivial geometry (brane tension) at the brane junctions. By introducing such terms in a Gauss-Bonnet form, we give an effective description of localized gravity on the singular delta-function branes. There exists a non-vanishing brane tension at the four-dimensional brane intersection of two 4-branes. Importantly, we give explicit expressions of the graviton propagator and show that the Randall-Sundrum single-brane model with a Gauss-Bonnet term in the bulk correctly gives a massless graviton on the brane as for the RS model. We explore some crucial features of completely localized gravity in the solitonic braneworld solutions obtained with a choice (\xi=1) of solutions. The no-go theorem known for Einstein's theory may not apply to the \xi=1 solution. As complementary discussions, we provide an effective description of the power-law corrections to Newtonian gravity on the branes or at the common intersection thereof.Comment: 19 pages, LaTeX, Revised/Published Versio

    On compatibility of string effective action with an accelerating universe

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    In this paper, we fully investigate the cosmological effects of the moduli dependent one-loop corrections to the gravitational couplings of the string effective action to explain the cosmic acceleration problem in early (and/or late) universe. These corrections comprise a Gauss-Bonnet (GB) invariant multiplied by universal non-trivial functions of the common modulus σ\sigma and the dilaton ϕ\phi. The model exhibits several features of cosmological interest, including the transition between deceleration and acceleration phases. By considering some phenomenologically motivated ansatzs for one of the scalars and/or the scale factor (of the universe), we also construct a number of interesting inflationary potentials. In all examples under consideration, we find that the model leads only to a standard inflation (w1w \geq -1) when the numerical coefficient δ\delta associated with modulus-GB coupling is positive, while the model can lead also to a non-standard inflation (w<1w<-1), if δ\delta is negative. In the absence of (or trivial) coupling between the GB term and the scalars, there is no crossing between the w1w -1 phases, while this is possible with non-trivial GB couplings, even for constant dilaton phase of the standard picture. Within our model, after a sufficient amount of e-folds of expansion, the rolling of both fields ϕ\phi and σ\sigma can be small. In turn, any possible violation of equivalence principle or deviations from the standard general relativity may be small enough to easily satisfy all astrophysical and cosmological constraints.Comment: 30 pages, 8 figures; v2 significant changes in notations, appendix and refs added; v3 significant revisions, refs added; v4 appendix extended, new refs, published versio

    Prescribing patterns in patients with chronic liver and kidney disease in a tertiary care hospital

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    Background: Liver diseases are major cause of mortality and morbidity worldwide. It is the 12th leading cause of death liver diseases can be classified as acute if the onset of symptom does not exceed six months or chronic if symptoms persist beyond this period. According to the recently available World Health Organization. The aim of study is to facilitate rational use of medicines. Methods: This study is a prospective, observational, single center study which include patients aged ≥18 years, diagnosis of liver diseases with or without co-morbidities and is conducted at out-patient of Medicine department, Rajindra Medical College and Hospital, Patiala. Results: In this study, total of 97 prescriptions of patients with liver disease were analyzed. Out of 97 patients, the majority of patients were male. In ALD, males were 32 (78%) whereas female were 9 (22%) while in CLD males were 47 (84%) and females were 9 (16%).While observing the LFT profile of patients with ALD common tests were observed which includes total bilirubin (1.82±2.42), SGOT (96.81±117.49) and SGPT (94.78±142.94) and in patients with CLD common tests were observed which includes total bilirubin (2.50±3.63), SGOT (67.50±43.04), SGPT (47.10±33.12), blood urea (46.92±24.14) and alkaline phosphatase (147.02±63.14). Conclusions: The study interprets the prescribing pattern of drugs used in patients with ALD and CLD and observed that vitamins and minerals and antibiotics were the most prescribed in order to avoid further complications followed by hepatoprotective agents, antiulcer drugs, antihypertensives and laxatives.

    Late-time Cosmic Dynamics from M-theory

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    We consider the behaviour of the cosmological acceleration for time-dependent hyperbolic and flux compactifications of M-theory, with an exponential potential. For flat and closed cosmologies it is seen that a positive acceleration is always transient for both compactifications. For open cosmologies, both compactifications can give at late times periods of positive acceleration. As a function of proper time this acceleration has a power law decay and can be either positive, negative or oscillatory.Comment: 10 pages, LaTeX, 2 figure

    Chemically gated electronic structure of a superconducting doped topological insulator system

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    Angle resolved photoemission spectroscopy is used to observe changes in the electronic structure of bulk-doped topological insulator Cux_xBi2_2Se3_3 as additional copper atoms are deposited onto the cleaved crystal surface. Carrier density and surface-normal electrical field strength near the crystal surface are estimated to consider the effect of chemical surface gating on atypical superconducting properties associated with topological insulator order, such as the dynamics of theoretically predicted Majorana Fermion vortices

    Exchange-Coupling Behavior in SrFe12O19/La0.7Sr0.3MnO3 Nanocomposites

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    Magnetically hard-soft (100-x) SrFe12O19–x wt % La0.7Sr0.3MnO3 nanocomposites were synthesized via a one-pot auto-combustion technique using nitrate salts followed by heat treatment in air at 950 °C. X-ray diffraction (XRD), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM) were used to characterize the structural and magnetic properties of the samples. XRD spectra revealed the formation of a mixture of ferrite and magnetite phases without any trace of secondary phases in the composite. Microstructural images show the proximity grain growth of both phases. The room temperature hysteresis loops of the samples showed the presence of exchange-coupling between the hard and soft phases of the composite. Although saturation magnetization reduced by 41%, the squareness ratio and coercivity of the nanocomposite improved significantly up to 6.6% and 81.7%, respectively, at x = 40 wt % soft phase content in the nanocomposite. The enhancement in squareness ratio and coercivity could be attributed to the effective exchange-coupling interaction, while the reduction in saturation magnetization could be explained on the basis of atomic intermixing between phases in the system. Overall, these composite particles exhibited magnetically single-phase behavior. The adopted synthesis method is low cost and rapid and results in pure crystalline nanocomposite powder. This simple method is a promising way to tailor and enhance the magnetic properties of oxide-based hard-soft magnetic nanocomposites

    Proposing a Multi-lingual Translation Scheme Utilizing the Extensible Markup Language XML

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    The paper proposes a new idea concerning a Multi-lingual translation scheme utilizing the newly evolving Internet tag language, Extensible Markup Language XML. The data description property of XML can be used to create an effective system to translate documents. First of all the XML tagged document of a source language is prepared manually. These tags are not only for the words but also for the grammatical structure, or for example, the phrase structure grammar, so that the analytical process of the translation can be reduced to a level suitable for many Internet applications. Next, XML document type definitions (DTDs) of grammatical structures of different languages are created. In the translation process the source sentences are broken down into pieces and then categorized to the respective DTDs to which they belong. The sentence structure of each language serves as a main structure tree, the broken elements are mapped with the elements of the DTD accordingly, which consequently maps them with the relative elements of the target language structure tree and the appropriate transformations are made. Among the possible transformation patterns, the most appropriate one is selected as an output
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