2,145 research outputs found

    Oblique propagation of arbitrary amplitude electron acoustic solitary waves in magnetized kappa-distributed plasmas

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    The linear and nonlinear properties of large amplitude electron-acoustic waves are investigated in a magnetized plasma comprising two distinct electron populations (hot and cold) and immobile ions. The hot electrons are assumed to be in a non-Maxwellian state, characterized by an excess of superthermal particles, here modelled by a kappa-type long-tailed distribution function. Waves are assumed to propagate obliquely to the ambient magnetic field. Two types of electrostatic modes are shown to exist in the linear regime, and their properties are briefly analyzed. A nonlinear pseudopotential type analysis reveals the existence of large amplitude electrostatic solitary waves and allows for an investigation of their propagation characteristics and existence domain, in terms of the soliton speed (Mach number). The effects of the key plasma configuration parameters, namely, the superthermality index and the cold electron density, on the soliton characteristics and existence domain, are studied. The role of obliqueness and magnetic field are discussed.Comment: Submitted to Plasma Physics and Controlled Fusio

    Determinants of adoption and preferences for Aman rice mutant variety Binadhan-7 cultivation in Bangladesh

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    This study was conducted in fourteen agricultural regions of Bangladesh namely-Mymensingh, Jashore, Cumilla, Bogura, Rajshahi, Sylhet, Dinajpur, Rangpur, Dhaka, Khulna, Chattagram, Rangamati, Barishal and Faridpur. The specific objectives of the present study were: i) to examine the determinants to adoption of rice mutant variety Binadhan-7; and ii) to identify the major preferences and constraints of rice mutant variety Binadhan-7 cultivation; A multistage stratified random sampling technique was used to collect the data. Marginal coefficients indicate that if male farmers increased by 100%, the probability of adopting Binadhan-7 variety would increase at 38 times more likely to adopt the variety. If the farm size of Binadhan-7 increased by 100%, the probability of adopting the variety would be increased by 0.07%. A farmer who has access to agricultural extension service is about 39 times more likely to adopt the variety. Again, if the yield increased by 100%, adopting the varieties would increase by 0.08%. The marginal coefficients of duration and soil fertility are negatively significant, indicating that if these two variables increased by 100%, the probability of adopting the varieties would decrease by 0.18% and 28%, respectively. Among the preferences, the highest preference was 88.93% for short duration followed by poverty reduction (88.57%), and lastly high yielding (81.43%). Among the constraints, the highest constraint was 80.71% for high labour price followed by lack of godown (69.64%), marketing problem (67.50%), destroy by bird (66.79%) and lack of quality seed (48.93%)

    Effect of chitosan and acetic acid on the shelf life of sea bass fillets stored at refrigerated temperature

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    Considering the necessity on the use of chitosan and acetic acid as an antimicrobial and antioxidant agents, an attempt was made to study their effect on Asian sea bass fillets stored at refrigerated temperature of 4±1°C. The effectiveness of different antimicrobials (Chitosan and Acetic acid) were measured by disk diffusion method against five bacterial strains (E. coli, Vibrio parahaemolyticus, Staphylococcus aureus, Proteus mirabilis and Pseudomonas fragi) with 1% Acetic acid as (T1), 1% Acetic acid + 1% Chitosan as (T2), 1% Acetic acid + 2% Chi-tosan as (T3) and distilled water as control (C).T2 was more effective in inhibiting all the bacteria except Pseudomo-nas fragi. Treatment T1 was found to be more effective against it whereas the action of T3 on the bacterial strains was also effective but less than the other two treatments. Further, antioxidant property of the treatments were measured by DPPH method which indicated that T3 showed highest % of antioxidative activity (3.94%) followed by T1 (3.85%), T2 (2.62%), and C (1.788%).Thus, it is observed that the antioxidant activity was found to be increased with the increasing concentration of chitosan. Application of chitosan and acetic acid coatings on Asian sea bass ( Lates calcarifer) fillets successfully controlled the TVB-N values, PV and TBA values (p<0.05) when compared to control sample and among all the treatments T2 was found to be the best. Coating of chitosan and acetic acid on the fillets also resulted in improvement of sensory scores as well as acceptability under refrigerated condition

    The Problem of Inertia in Friedmann Universes

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    In this paper we study the origin of inertia in a curved spacetime, particularly the spatially flat, open and closed Friedmann universes. This is done using Sciama's law of inertial induction, which is based on Mach's principle, and expresses the analogy between the retarded far fields of electrodynamics and those of gravitation. After obtaining covariant expressions for electromagnetic fields due to an accelerating point charge in Friedmann models, we adopt Sciama's law to obtain the inertial force on an accelerating mass mm by integrating over the contributions from all the matter in the universe. The resulting inertial force has the form F=kmaF = -kma, where k<1k < 1 depends on the choice of the cosmological parameters such as ΩM\Omega_{M}, ΩΛ\Omega_{\Lambda}, and ΩR\Omega_{R} and is also red-shift dependent.Comment: 10 page

    Missense mutations at homologous positions in the fourth and fifth laminin A G-like domains of eyes shut homolog cause autosomal recessive retinitis pigmentosa

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    Purpose: To describe two novel mutations in the eyes shut homolog (EYS) gene in two families with autosomal recessive retinitis pigmentosa (arRP) from Pakistan and Indonesia. Methods: Genome-wide linkage and homozygosity mapping were performed using single nucleotide polymorphism microarray analysis in affected members of the two arRP families. Sequence analysis was performed to identify genetic changes in protein coding exons of EYS. Results: In the Indonesian and Pakistani families, homozygous regions encompassing the EYS gene at 6q12 were identified, with maximum LOD scores of 1.8 and 3.6, respectively. Novel missense variants in the EYS gene (p.D2767Y and p.D3028Y) were found in the Pakistani and Indonesian families, respectively, that co-segregate with the disease phenotype. Interestingly, the missense variants are located at the same homologous position within the fourth and fifth laminin A G-like domains of EYS. Conclusions: To date, mostly protein-truncating mutations have been described in EYS, while only few patients have been described with pathogenic compound heterozygous missense mutations. The mutations p.D2767Y and p.D3028Y described in this study affect highly conserved residues at homologous positions in laminin A G-like domains and support the notion that missense mutations in EYS can cause arRP

    Comparative Analysis of Downlink Packet Scheduling Algorithms in 3GPP LTE Networks

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    Long Term Evolution (LTE) mobile network aims to support high speed network services even in highmobility scenarios. To achieve this goal, LTE adopts some advanced features in Radio Resource Management (RRM) procedures. Among them, LTE packet scheduling plays a fundamental role in maximising system performance. In this paper, a comparative analysis on the performances of Proportional Fair (PF), Exponential/Proportional Fair (EXP/PF), Exponential (EXP) Rule, MaximumLargest Weighted Delay First (M-LWDF), Logarithmic (LOG) Rule and Frame Level Scheduler (FLS) LTE downlink packet scheduling algorithms is reported. Performance is evaluated in single cell with interference environment while increasing user number and user speed. Results show that for multimedia flow, FLS scheme outperforms other five schemes in terms of packet delay, packet loss ratio, and average throughput, whereas for best-effort flow, EXP-PF scheme shows better average throughput performance on average as compared with other algorithms being considered herein

    Simulation of Traffic Flow Model with Traffic Controller Boundary

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    This paper considers a fluid dynamic traffic flow model appended with a closure linear velocity-density relationship which provides a first order hyperbolic partial differential equation (PDE) and is treated as an initial boundary value problem (IBVP). We consider the boundary value in such a way that one side of highway treat like there is a traffic controller at that point. We present the analytic solution of the traffic flow model as a Cauchy problem. A numerical simulation of the traffic flow model (IBVP) is performed based on a finite difference scheme for the model with two sided boundary conditions and a suitable numerical scheme for this is the Lax-Friedrichs scheme. Solution figure from our scheme indicates a desired result that amplitude and frequency of cars density and velocity reduces as time grows. Also at traffic controller point, velocity and density values change as desired manner. In further, we also want to introduce anisotropic behavior of cars(to get more realistic picture) which has not been considered here. Doi: 10.12777/ijse.5.1.25-30 [How to cite this article: Sultana, N., Parvin, M. , Sarker, R., Andallah, L.S. (2013). Simulation of Traffic Flow Model with Traffic Controller Boundary. International Journal of Science and Engineering, 5(1),25-30. Doi: 10.12777/ijse.5.1.25-30

    An inter comparison of the upper critical fields (Hc2) of different superconductors - YBa2Cu3O7, MgB2, NdFeAsO0.8F0.2, FeSe0.5Te0.5 and Nb2PdS5

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    Here we report the comparison of the upper critical fields of different superconductors being calculated by two different theories i.e., Werthamer Helfand Hohenburg (WHH) and Ginzberg Landau (GL). All the samples are synthesized through previously known solid state reaction route. Phase purity is determined from the Rietveld refinement of powder X-Ray diffraction (XRD) data. High field (up to 14Tesla) magneto transport \r{ho}(T)H of different superconductors is studied to estimate their upper critical field (Hc2). The present inter comparison covers from Cuprates (YBa2Cu3O7) - Borides (MgB2) - Fe pnictides (NdFeAsO0.8F0.2) and chalcogenides (FeSe0.5Te0.5) to robust Nb2PdS5. The upper critical fields [Hc2(T)] at zero temperature are calculated by extrapolating the data using GL and WHH equations.Comment: 10 Pages text + Figs: Short MS: Letter-J.Sup.Novel.Ma

    Electron-Ion Recombination Rate Coefficients and Photoionization Cross Sections for Astrophysically Abundant Elements. V. Relativistic calculations for Fe XXIV and Fe XXV for X-ray modeling

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    Photoionization and recombination cross sections and rate coefficients are calculated for Li-like Fe XXIV and He-like Fe XXV using the Breit-Pauli R-matrix (BPRM) method. A complete set of total and level-specific parameters is obtained to enable X-ray photoionization and spectral modeling. The ab initio calculations for the unified (e + ion) recombination rate coefficients include both the non-resonant and the resonant recombination (radiative and di-electronic recombination, RR and DR, respectively) for (e + Fe XXV) -> Fe XXIV and (e + Fe XXVI) -> Fe XXV. The level specific rates are computed for all fine structure levels up to n = 10, enabling accurate computation of recombination-cascade matrices and effective rates for the X-ray lines. The total recombination rate coefficients for both Fe XXIV and Fe XXV differ considerably, by several factors, from the sum of RR and DR rates currently used to compute ionization fractions in astrophysical models. As the photoionization/recombination calculations are carried out using an identical eigenfunction expansion, the cross sections for both processes are theoretically self-consistent; the overall uncertainty is estimated to be about 10-20%. All data for Fe XXIV and Fe XXV (and also for H-like Fe XXVI, included for completeness) are available electronically.Comment: 31 pages, 10fug
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