Parabolic H-measures

Classical H-measures introduced by Tartar (1990) and independently by Gérard (1991) are not well suited for the study of parabolic equations. Recently, several parabolic variants have been proposed, together with a number of applications. We introduce a new parabolic variant (and call it the parabolic H-measure), which is suitable for these known applications. Moreover, for this variant we prove the localisation and propagation principle, establishing a basis for more demanding applications of parabolic H-measures, similarly as it was the case with classical H-measures. In particular, the propagation principle enables us to write down a transport equation satisfied by the parabolic H-measure associated to a sequence of solutions of a Schrödinger type equation. Some applications to specific equations are presented, illustrating the possible use of this new tool. A comparison to similar results for classical H-measures has been made as well

Modelling fixed plant and algal dynamics in rivers: an application to the River Frome

The development of eutrophication in river systems is poorly understood given the complex relationship between fixed plants, algae, hydrodynamics, water chemistry and solar radiation. However there is a pressing need to understand the relationship between the ecological status of rivers and the controlling environmental factors to help the reasoned implementation of the Water Framework Directive and Catchment Sensitive Farming in the UK. This research aims to create a dynamic, process-based, mathematical in-stream model to simulate the growth and competition of different vegetation types (macrophytes, phytoplankton and benthic algae) in rivers. The model, applied to the River Frome (Dorset, UK), captured well the seasonality of simulated vegetation types (suspended algae, macrophytes, epiphytes, sediment biofilm). Macrophyte results showed that local knowledge is important for explaining unusual changes in biomass. Fixed algae simulations indicated the need for the more detailed representation of various herbivorous grazer groups, however this would increase the model complexity, the number of model parameters and the required observation data to better define the model. The model results also highlighted that simulating only phytoplankton is insufficient in river systems, because the majority of the suspended algae have benthic origin in short retention time rivers. Therefore, there is a need for modelling tools that link the benthic and free-floating habitats

Extended Einstein-Cartan theory a la Diakonov: the field equations

Diakonov formulated a model of a primordial Dirac spinor field interacting gravitationally within the geometric framework of the Poincar\'e gauge theory (PGT). Thus, the gravitational field variables are the orthonormal coframe (tetrad) and the Lorentz connection. A simple gravitational gauge Lagrangian is the Einstein-Cartan choice proportional to the curvature scalar plus a cosmological term. In Diakonov's model the coframe is eliminated by expressing it in terms of the primordial spinor. We derive the corresponding field equations for the first time. We extend the Diakonov model by additionally eliminating the Lorentz connection, but keeping local Lorentz covariance intact. Then, if we drop the Einstein-Cartan term in the Lagrangian, a nonlinear Heisenberg type spinor equation is recovered in the lowest approximation.Comment: 13 pages, no figure

Foreword

This work reports on the performances of ohmic contacts fabricated on highly p-type doped 4H-SiC epitaxial layer selectively grown by vapor-liquid-solid transport. Due to the very high doping level obtained, the contacts have an ohmic behavior even without any annealing process. Upon variation of annealing temperatures, it was shown that both 500 and 800 °C annealing temperature lead to a minimum value of the Specific Contact Resistance (SCR) down to 1.3×10−6 Ω⋅cm2. However, a large variation of the minimum SCR values has been observed (up to 4×10−4 Ω⋅cm2). Possible sources of this fluctuation have been also discussed in this paper

Characterization of PPAR-gamma 1 and PPAR-gamma 2 in Knockin and Knockout Mouse Models

The global epidemic of obesity and type II diabetes has led to a growing interest in the underlying mechanisms of metabolic diseases. The peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the nuclear receptor superfamily, and is vital for the transcriptional regulation of adipogenesis, insulin sensitivity and lipid metabolism. In the mouse model, it has been demonstrated that global knockout of PPARγ leads to severe metabolic disturbance, resulting in embryonic lethality. However, the specific regulatory roles of its two protein isoforms, PPARγ1 and PPARγ2, remain uncertain, due to limitations of reagents and appropriate mouse models. To investigate the hypothesis that PPARγ1 and PPARγ2 are functionally distinct, we generated PPARγ1 and PPARγ2 tagged mice using CRISPR-Cas9 technology. PPARγ1 and PPARγ2 specific knockout mice were also generated incidentally during this process, via aberrant recombination. By reverse-transcription quantitative PCR (RT-qPCR), and western blot, we confirmed the presence of the appropriate tags in our PPARγ1 and PPARγ2 tagged mice, with no significant disruption to mRNA or protein expression. Furthermore, we found that PPARγ1 mRNA and protein expression levels were reduced in our PPARγ1 knockout model, compared to the wild type. Interestingly, we found that there was a complete loss of PPARγ2 protein expression, despite an increase in PPARγ2 mRNA expression in our PPARγ2 knockout model. These data suggest that we have successfully generated PPARγ1 and PPARγ2 knockin and knockout mice. Our mouse models provide a valuable tool to study the individual roles of PPARγ1 and PPARγ2 in adipogenesis, insulin sensitivity and metabolic disease

Genetic Diversity of Army worm, Spodoptera mauritia Isolated from Kerala, India

The army worm Spodoptera mauritia is one of the major pests of paddy which is widely distributed in the Indian subcontinent, East and southern Asia and in the Australian region. Generally the army worms infest paddy crops of less than 20-25 days old. They are gregarious, defoliating the paddy and move from one field to other in large number like an army. The classification of Spodoptera species is mainly based on the structure of the male genitalia, antenna and the colour pattern of the wing. Here we report the partial coding sequence of cytochrome oxidase sub-unit I (COI) sequence of army worm isolated from Kerala, India which is identical to that isolated from Japan. This study highlights the geographical distribution and genetic diversity of army worm in paddy cultivating countries

Parallel Shooting Sequential Quadratic Programming for Nonlinear MPC Problems

In this paper, we propose a parallel shooting algorithm for solving nonlinear model predictive control problems using sequential quadratic programming. This algorithm is built on a two-phase approach where we first test and assess sequential convergence over many initial trajectories in parallel. However, if none converge, the algorithm starts varying the Newton step size in parallel instead. Through this parallel shooting approach, it is expected that the number of iterations to converge to an optimal solution can be decreased. Furthermore, the algorithm can be further expanded and accelerated by implementing it on GPUs. We illustrate the effectiveness of the proposed Parallel Shooting Sequential Quadratic Programming (PS-SQP) method in some benchmark examples for nonlinear model predictive control. The developed PS-SQP parallel solver converges faster on average and especially when significant nonlinear behaviour is excited in the NMPC horizon.Comment: 7 pages, 6 figures, submitted and accepted for the 7th IEEE Conference on Control Technology and Applications (CCTA) 202