Spin-triplet superconductivity in a weak-coupling Hubbard model for the quasi-one-dimensional compound Li0.9_{0.9}Mo6_6O17_{17}

The purple bronze Li$_{0.9}$Mo$_6$O$_{17}$ is of interest due to its quasi-one-dimensional electronic structure and the possible Luttinger liquid behavior resulting from it. For sufficiently low temperatures, it is a superconductor with a pairing symmetry that is still to be determined. To shed light on this issue, we analyze a minimal Hubbard model for this material involving four molybdenum orbitals per unit cell near quarter filling, using asymptotically exact perturbative renormalization group methods. We find that spin triplet odd-parity superconductivity is the dominant instability. Approximate nesting properties of the two quasi-one-dimensional Fermi surfaces enhance certain second-order processes, which play crucial roles in determining the structure of the pairing gap. Notably, we find that the gap has accidental nodes, i.e. it has more sign changes than required by the point-group symmetry.Comment: Update

Optimal Tc_c of cuprates: role of screening and reservoir layers

We explore the role of charge reservoir layers (CRLs) on the superconducting transition temperature of cuprate superconductors. Specifically, we study the effect of CRLs with efficient short distance dielectric screening coupled capacitively to copper oxide metallic layers. We argue that dielectric screening at short distances and at frequencies of the order of the superconducting gap, but small compared to the Fermi energy can significantly enhance T$_c$, the transition temperature of an unconventional superconductor. We discuss the relevance of our qualitative arguments to a broader class of unconventional superconductors.Comment: 8 Pages, 4 figure

A prospective study of surgical management of distal tibial fractures treated with minimally invasive percutaneous plate osteosynthesis using locking compression plate

Background: Distal tibial fractures are unique and represent a significant challenge in their management. Factors affecting the outcome include location of fractures, proximity to ankle joint, less soft tissue coverage, comminution, unstable and compound fractures, method of treatment and quality of reduction. Distal tibial fractures traditionally were treated with different modalities, LCP with MIPPO (minimally invasive percutaneous plate osteosynthesis) being one of the recent advances.Methods: Clinical, prospective observational study was conducted at J.J.M. Medical College, Davangere between October 2014 to September 2016. 21 patients with distal 1/3rd tibial fractures with or without intra-articular extensions were included in this study.  All 21 patients treated with LCP by MIPPO were followed for 6 months with clinical and radiological assessment, including ankle scoring system (Olerud and Mollander).Results: 21 patients with age between 23-65 years (mean 41.6 years) were treated with LCP by MIPPO during the study period. All the patients were followed up at 6 weeks, 12 weeks, 6 months and at 1 year with x-ray and ankle scoring system. All the patients had complete union between 14 weeks to 24 weeks with ankle score between excellent and good in majority of the patients.  There were 2 cases of delayed union, 3 superficial skin infections and 3 cases of ankle stiffness. Conclusions: Study concludes LCP with MIPPO is a safe, reliable technique to achieve complete union of difficult fractures.

Spin-Orbit Coupling in LaAlO3_3/SrTiO3_3 interfaces: Magnetism and Orbital Ordering

The combination of Rashba spin-orbit coupling and electron correlations can induce unusual phenomena in the metallic interface between SrTiO$_3$ and LaAlO$_3$. We consider effects of Rashba spin-orbit coupling at this interface in the context of the recent observation of anisotropic magnetism. Firstly, we show how Rashba spin-orbit coupling in a system near a band-edge can account for the observed magnetic anisotropy. Secondly, we investigate the coupling between in-plane magnetic-moment anisotropy and nematicity in the form of an orbital imbalance between d$_{xz}$ / d$_{yz}$ orbitals. We estimate this coupling to be substantial in the low electron density regime. Such an orbital ordering can affect magneto transport

Modeling IS Activities for Business Process Reengineering : A Colored Petri Net Approach

The day to day functioning of any organization involves many business processes. Each business process is comprised of different activities. The identification of activities and their cost drivers is a critical factor for successful Business Process Reengineering. Since the resources used by the activities form an integral part of the model, the identification of the cost drivers is also simplified. This paper details the following : 1. It proposesthe use of colored Petri nets for process modeling. Brimson(1991) identifies the process modeling approach to activity analysis as useful since it graphically links the inputs and outputs among activities and identifies the information flow in the processes. However, use of process flow charts, which is most commonly used in activity analysis cannot capture some of the aspects of office processes, like supervision, general management, etc. In addition, representing the complex business logic associated with activities would be difficult in such flow models. The use of colored Petri nets overcomes this limitation, as business logic and various office processes can be easily represented. In addition, the complexity of the system is handled by resorting to hierarchical representation of the processes. 2. The paper applies the concept of activity based costing to the management of the IS processes in firms. The cost structure of these processes, to our knowledge, has not been studied from the activity based costing perspective. The article proposes the use of activity based costing for IS processes. Such analysis could help the organization in making operational as well as strategic decisions as related to its IS processe

Market Reactions To Patent Infringement Lawsuits In Information Technology Industry

Over the years the number of patent infringement lawsuits in the Information Technology industry has increased tremendously. The increase in patent disputes can be partly attributed to the increase in the number of patents issued. The number of patents issued for software developments alone has risen from 25 in 1970 to 600 in 1991. The total number of patents issued till 1992 was about 9000. The damages awarded to patentees in such litigations is substantial. It is argued that some of these high technology companies are using the intellectual property rights laws as a weapon to thwart competition in their markets. In the US, while the inventor is waiting for the patent on the invention, manufacturers may develop and begin using similar technology, but once the patent has been issued, the inventor can demand the damages from the manufacturer using the technology. Many of the top executives believe that it is beneficial to settle infringement cases than dispute it in a court of law. This view is again raised in the patent infringement dispute between Intel Corp. and AMD Corp., who spent almost $200 million on the patent dispute over several years. To our knowledge no empirical study has been undertaken to study the impact of patent infringement lawsuits on the information technology companies involved. Though markets analysts have suggested that the market value of the firms fluctuates in accordance with the direction of the lawsuit proceedings, no concrete evidence of these effects have been shown in the literature. This study aims to study the impact of the patent infringement lawsuits and the lawsuit decisions on the IT companies involved. The impact on the stock holder returns is used as the empirical evidence of the impact of the litigation on the IT company. Findings of thestudy are expected to provide valuable insights into market perception of the ethical issues in a high technology industry. More specifically, how does the market view the ethical conduct of an IT company? Does it impose a high risk on a company suspectedof unethical conduct in its business strategies?. In addition to the ethical issues involved, the economic viability of fighting a law suit is also examined, i.e., does the market perceive a net benefit or loss to the company as a result of fighting a lawsuit? Does the market perceive a net benefit or loss to the company as a result of the decision made on the law suit?. The findings of the study would be useful to both the policy formulators and managers alik

Fracture Simulation of Concrete Beams to assess softening behavior by varying different fractions of Aggregates

Simulating the concrete fracture unlike other elastic and brittle materials quite different due to its quasibrittleness. The present research focussed on assess softening behavior by varying different fractions of aggregates  and cement matrix in micro details. Extended Finite Element Method (XFEM) for crack modeling implemented for simulating and visualizing crack propagation through Cement matrix, Interfacial Transition Zone (ITZ) and Aggregates . This approach permits the initializing crack by from enrichment zone and propagation of crack through element by traction separation law .The crack formation initiates when the maximum principal tensile stress reaches the tensile strength. The work involves creating python script for iterative process of random distribution of aggregates with in the matrix using Monte Carlo method and creating Cohesive zone element for zero thickness ITZ. introduces a finite element modeling technique for investigating multiscale fracture characteristics. This approach encompasses multiple levels of analysis, including the generation of aggregate particles using a Monte Carlo method implemented via a Python script. Additionally, we replicate the Interfacial Transition Zone (ITZ) between aggregate and mortar in the model. The load-deflection curves can be used to assess the softening behavior of concrete and suggest the realistic fraction of coarse aggregate in mix proportion to impart more ductility to beams

Stage-specific action of matrix metalloproteinases influences progressive hereditary kidney disease.

BackgroundGlomerular basement membrane (GBM), a key component of the blood-filtration apparatus in the in the kidney, is formed through assembly of type IV collagen with laminins, nidogen, and sulfated proteoglycans. Mutations or deletions involving alpha3(IV), alpha4(IV), or alpha5(IV) chains of type IV collagen in the GBM have been identified as the cause for Alport syndrome in humans, a progressive hereditary kidney disease associated with deafness. The pathological mechanisms by which such mutations lead to eventual kidney failure are not completely understood.Methods and findingsWe showed that increased susceptibility of defective human Alport GBM to proteolytic degradation is mediated by three different matrix metalloproteinases (MMPs)--MMP-2, MMP-3, and MMP-9--which influence the progression of renal dysfunction in alpha3(IV)-/- mice, a model for human Alport syndrome. Genetic ablation of either MMP-2 or MMP-9, or both MMP-2 and MMP-9, led to compensatory up-regulation of other MMPs in the kidney glomerulus. Pharmacological ablation of enzymatic activity associated with multiple GBM-degrading MMPs, before the onset of proteinuria or GBM structural defects in the alpha3(IV)-/- mice, led to significant attenuation in disease progression associated with delayed proteinuria and marked extension in survival. In contrast, inhibition of MMPs after induction of proteinuria led to acceleration of disease associated with extensive interstitial fibrosis and early death of alpha3(IV)-/- mice.ConclusionsThese results suggest that preserving GBM/extracellular matrix integrity before the onset of proteinuria leads to significant disease protection, but if this window of opportunity is lost, MMP-inhibition at the later stages of Alport disease leads to accelerated glomerular and interstitial fibrosis. Our findings identify a crucial dual role for MMPs in the progression of Alport disease in alpha3(IV)-/- mice, with an early pathogenic function and a later protective action. Hence, we propose possible use of MMP-inhibitors as disease-preventive drugs for patients with Alport syndrome with identified genetic defects, before the onset of proteinuria