The Euler class group of a polynomial algebra II

Podeu consultar la versió en castellà a:http://hdl.handle.net/11703/8769

A note on complex L

Some characterizations of complex L1-predual spaces are proved

Chaotic Dynamics and Complexity in Real and Physical Systems

Emergence of chaos and complex behavior in real and physical systems has been discussed within the framework of nonlinear dynamical systems. The problems investigated include complexity of Child’s swing dynamics , chaotic neuronal dynamics (FHN model), complex Food-web dynamics, Financial model (involving interest rate, investment demand and price index) etc. Proper numerical simulations have been carried out to unravel the complex dynamics of these systems and significant results obtained are displayed through tables and various plots like bifurcations, attractors, Lyapunov exponents, topological entropies, correlation dimensions, recurrence plots etc. The significance of artificial neural network (ANN) framework for time series generation of some dynamical system is suggested

Two component quantum walk in one-dimensional lattice with hopping imbalance

We investigate the two-component quantum walk in one-dimensional lattice. We show that the inter-component interaction strength together with the hopping imbalance between the components exhibit distinct features in the quantum walk for different initial states. When the walkers are initially on the same site, both the slow and fast particles perform independent particle quantum walks when the interaction between them is weak. However, stronger inter-particle interactions result in quantum walks by the repulsively bound pair formed between the two particles. For different initial states when the walkers are on different sites initially, the quantum walk performed by the slow particle is almost independent of that of the fast particle, which exhibits reflected and transmitted components across the particle with large hopping strength for weak interactions. Beyond a critical value of the interaction strength, the wave function of the fast particle ceases to penetrate through the slow particle signalling a spatial phase separation. However, when the two particles are initially at the two opposite edges of the lattice, then the interaction facilitates the complete reflection of both of them from each other. We analyze the above mentioned features by examining various physical quantities such as the on-site density evolution, two-particle correlation functions and transmission coefficients.Comment: Accepted Version(Scientific Reports

Clinicopathological spectrum of renal biopsies in children – A single center experience from Eastern India

Background: Renal diseases are common in childhood and they often present with diagnostic challenges. Renal biopsy is of major importance in diagnosing many renal diseases in children. The aim of this study was to evaluate the clinicopathological aspect of renal diseases underwent biopsy in children in a tertiary care teaching institute in Eastern India. Materials and methods: This cross sectional study was conducted on children (≤12 year) admitted with difficult to treat renal disorders in Pediatric ward and thorough evaluations confirmed the requirement of renal biopsy. Sixty one (61) children satisfying the inclusion and exclusion criteria were enrolled in our study. Period of study was from February 2021 to July 2022. Results: In this study, males were 31 and females were 30 in numbers. The mean age was 6.77± 3.42 years. The indications for renal biopsy were steroid resistant nephrotic syndrome (SRNS) (49.18%), systemic lupus erythematosus (SLE) (29.51%), acute glomerulonephritis (AGN) (16.39%), and others. The major bulks of histopathological findings revealed focal segmental glomerulosclerosis (FSGS), membranoproliferative glomerulonephritis (MPGN) and minimal change disease (MCD) in 45.9%, 32.8% and 13.1% respectively. Hypertension was present in 58.1% and hematuria in 64.5% of cases (p value 0.001). Conclusion: SRNS (49.18%) was the most common indication of renal biopsy and FSGS (45.9%) was the most common histopathological finding in our study. This study provides data on biopsy proven childhood renal disorders from this region

Fundamental Studies of the Silicon Carbide MOS Structure

The ability to thermally grow SiO2 on silicon carbide (SiC) has made Metal Oxide Semiconductor (MOS) devices feasible in SiC. Critical in their development is a thorough understanding of the SiC MOS structure itself. Three important steps have been accomplished toward this goal. First, tools to characterize the oxide/SiC interface have been developed. The room temperature photo C-V, the high-low, and conductance-frequency methods constitute quite an arsenal of interface characterization techniques. However, due to their inability to measure across the wide bandgap and the need for the MOS capacitor test structure, the current arsenal needs to be complemented with the charge pumping (CP) method which provides DIT across midgap and is measured directly on MOSFETs. Second, the interface has been optimized. Work to in this area has lowered DIT to the mid-1010 cm−2eV−1 range near midgap and Q F to a record low 5 × 1011 cm−2. But, we have made direct measurements of a high density of interface states near the conduction band. Hence, future work must concentrate on the conduction band states before SiC enjoys a true device quality interface. The bottom line is that SiC is still missing the analog of the hydrogen anneal from silicon MOS technology. Finally, in order to transfer the technology from test structures to devices, device behavior must be better understood, namely the inversion channel mobility, which currently is the limiting agent in MOS device development. Mobilities on 6H-SiC approach a record high 100 cm2/Vs while the corresponding values on 4H-SiC are at least an order of magnitude lower for simultaneously processed MOSFETs. Process optimization of the 4H has resulted in mobilities of 25 cm2/Vs. The low mobilities on these devices can be explained with the high density of interface states near the conduction band. They lower mobility by trapping and Coulombically scattering the mobile carriers in the channel. Clearly, the future of SiC MOS hinges on the reduction of the bandtail states near the conduction band