Some new mathematical features in cascade theory

AbstractThe fluctuation problem in cascade theory is viewed from the standpoint of the invariant imbedding method of Bellman et al. [1]. The correlation functions that are used in the description of the electromagnetic cascades are shown to obey a simple system of two component vector differential equations. The advantage of the present method over the conventional approach of writing down Kolmogorov forward equations for these functions lies in that we encounter 2 × 2 matrices of a particular type only. In view of the simplicity of the structure it is possible to generalize the equations to correlation functions of arbitrary order. The reduction in dimension from 2n × 2n matrices to only 2 × 2 matrices which may, at first sight, appear perplexing is due to the fact that each of the 2n elements that appear in the single system of differential equations, corresponding to the two different initial conditions, can be obtained by considering 2n disjoint systems of two component vector equations. The imbedding technique is also used to arrive at the independent differential equations satisfied by sequent product densities that are encountered in more comprehensive description of electromagnetic cascades

Serological Investigation of Bovine Brucellosis, Johne’s Disease and Infectious Bovine Rhinotracheitis in Two States of India

In the present study, serological diagnosis of brucellosis, Johne’s Disease (JD) and infectious bovine rhinotracheitis (IBR) was carried out in the states of Gujarat and Andhra Pradesh of India. Apparent prevalence of brucellosis was 7.57 % (true prevalence, 5.66%) in Gujarat and 12.27 % (true prevalence, 10.60%) in Andhra Pradesh. For JD apparent prevalence in Gujarat and Andhra Pradesh was 13.39% (true prevalence, 15.68%) and 16.26% (true prevalence, 19.31%) respectively. Apparent prevalence of IBR was found to be 23.94% (true prevalence, 18.20%) and 26.49% (true prevalence, 21.03%) in Gujarat and Andhra Pradesh respectively. The results of the study revealed that these diseases are highly prevalent in both the states; hence, there is an urgent need for adopting suitable control measures

Rabies Virus Infection in Domestic Buffaloes and Wild Animals in India

Rabies is one of the most significant diseases in India with severe health implication to humans, domestic and wild animals. In the present study, four concomitant incidents of rabies related deaths were recorded in the western province of India, Gujarat during 2012 - 2014. Brain samples were collected from two buffaloes, nilgai, and mongoose during these incidents and rabies virus was identified from these samples. Further genetic relationship of these isolates was determined and the rabies virus transmission among the wild and domestic mammals was established. Molecular epidemiology based on the glycoprotein ecto-domain and complete nucleoprotein gene showed that all the four isolates belonged to Arctic-like 1 lineage which is predominant in India. Phylogenetic analysis and time scaled evolutionary tree analysis indicated that the wild animals are playing an important role in the maintenance and also transmission of the rabies virus in India

Coconut-growing soils of Kerala: 2. Assessment of fertility and soil related constraints to coconut production

Growth, productivity and health of coconut plantations in humid tropics are influenced by soil qualities. Fertility of coconut-growing soils of Kerala was assessed by analysing samples drawn from the distinct agro-ecological regions of the state: Central and Eastern Palakkad, Northern Kerala, Central Kerala and Southern Kerala, Onattukara sandy plain and coastal sandy plain. The strongly acid soils of Northern and Central Kerala and Onattukara sandy plain are unfavorable for plant nutrient availability and microbial processes. Surface and sub-soils of Central Kerala and sandy plains have low levels of organic carbon. Available phosphorus was high in soils of Southern Kerala and Onattukara sandy plain. Plant available potassium was not adequate in these coconut-growing soils. The nutrient levels in soils of Central Kerala and sandy plain were extremely low. The same pattern was true for secondary nutrients calcium and magnesium. Soils of all regions have adequate levels of available sulphur, iron and manganese. Copper and zinc deficiency was recorded for laterite soils of central region and sandy soils of Onattukara and coastal plain. Plant available boron was deficient in all regions except for the soils of Southern Kerala. Molybdenum levels were marginal in coconut growing soils, except for the soils of Palakkad. Overhead climate and soil moisture availability does not constrain the palm in the state except for Eastern Palakkad where irrigation during dry period is an absolute necessity. The extensive areas of midland laterites and Onattukara sandy plain with strong acid reaction and aluminium in soil solution severely constrain coconut. The acid soils also suffer from deficiencies of potassium, calcium, magnesium, copper, zinc and boron. These soil related constraints affect coconut production significantly and alleviation of the same through liming and adequate application of deficient nutrients can ensure satisfactory yields from the palm

Electromigration-Induced Flow of Islands and Voids on the Cu(001) Surface

Electromigration-induced flow of islands and voids on the Cu(001) surface is studied at the atomic scale. The basic drift mechanisms are identified using a complete set of energy barriers for adatom hopping on the Cu(001) surface, combined with kinetic Monte Carlo simulations. The energy barriers are calculated by the embedded atom method, and parameterized using a simple model. The dependence of the flow on the temperature, the size of the clusters, and the strength of the applied field is obtained. For both islands and voids it is found that edge diffusion is the dominant mass-transport mechanism. The rate limiting steps are identified. For both islands and voids they involve detachment of atoms from corners into the adjacent edge. The energy barriers for these moves are found to be in good agreement with the activation energy for island/void drift obtained from Arrhenius analysis of the simulation results. The relevance of the results to other FCC(001) metal surfaces and their experimental implications are discussed.Comment: 9 pages, 13 ps figure

Anomaly analysis of Hawking radiation from Kaluza-Klein black hole with squashed horizon

Considering gravitational and gauge anomalies at the horizon, a new method that to derive Hawking radiations from black holes has been developed by Wilczek et al. In this paper, we apply this method to non-rotating and rotating Kaluza-Klein black holes with squashed horizon, respectively. For the rotating case, we found that, after the dimensional reduction, an effective U(1) gauge field is generated by an angular isometry. The results show that the gauge current and energy-momentum tensor fluxes are exactly equivalent to Hawking radiation from the event horizon.Comment: 15 pages, no figures, the improved version, accepted by Eur. Phys. J.

Magnetic Field Generation in Stars

Enormous progress has been made on observing stellar magnetism in stars from the main sequence through to compact objects. Recent data have thrown into sharper relief the vexed question of the origin of stellar magnetic fields, which remains one of the main unanswered questions in astrophysics. In this chapter we review recent work in this area of research. In particular, we look at the fossil field hypothesis which links magnetism in compact stars to magnetism in main sequence and pre-main sequence stars and we consider why its feasibility has now been questioned particularly in the context of highly magnetic white dwarfs. We also review the fossil versus dynamo debate in the context of neutron stars and the roles played by key physical processes such as buoyancy, helicity, and superfluid turbulence,in the generation and stability of neutron star fields. Independent information on the internal magnetic field of neutron stars will come from future gravitational wave detections. Thus we maybe at the dawn of a new era of exciting discoveries in compact star magnetism driven by the opening of a new, non-electromagnetic observational window. We also review recent advances in the theory and computation of magnetohydrodynamic turbulence as it applies to stellar magnetism and dynamo theory. These advances offer insight into the action of stellar dynamos as well as processes whichcontrol the diffusive magnetic flux transport in stars.Comment: 41 pages, 7 figures. Invited review chapter on on magnetic field generation in stars to appear in Space Science Reviews, Springe

Corrections to Hawking-like Radiation for a Friedmann-Robertson-Walker Universe

Recently, a Hamilton-Jacobi method beyond semiclassical approximation in black hole physics was developed by \emph{Banerjee} and \emph{Majhi}\cite{beyond0}. In this paper, we generalize their analysis of black holes to the case of Friedmann-Robertson-Walker (FRW) universe. It is shown that all the higher order quantum corrections in the single particle action are proportional to the usual semiclassical contribution. The corrections to the Hawking-like temperature and entropy of apparent horizon for FRW universe are also obtained. In the corrected entropy, the area law involves logarithmic area correction together with the standard inverse power of area term.Comment: 10 pages, no figures, comments are welcome; v2: references added and some typoes corrected, to appear in Euro.Phys.J.C; v3:a defect corrected. We thank Dr.Elias Vagenas for pointing out a defect of our pape

Hawking Radiation and Tunneling Mechanism for a New Class of Black Holes in Einstein-Gauss-Bonnet Gravity

We study the Hawking radiation in a new class of black hole solutions in the Einstein-Gauss-Bonnet theory. The black hole has been argued to have vanishing mass and entropy, but finite Hawking temperature. To check if it really emits radiation, we analyse the Hawking radiation using the original method of quantization of scalar field in the black hole background and the quantum tunneling method, and confirm that it emits radiation at the Hawking temperature. A general formula is derived for the Hawking temperature and backreaction in the tunneling approach. Physical implications of these results are discussed.Comment: 12 pages, v2: Title slightly changed. Motivation and discussions are elaborated, v3: typos corrected to match the published versio