Supersymmetric analogue of BC_N type rational integrable models with polarized spin reversal operators

We derive the exact spectra as well as partition functions for a class of $BC_N$ type of spin Calogero models, whose Hamiltonians are constructed by using supersymmetric analogues of polarized spin reversal operators (SAPSRO). The strong coupling limit of these spin Calogero models yields $BC_N$ type of Polychronakos-Frahm (PF) spin chains with SAPSRO. By applying the freezing trick, we obtain an exact expression for the partition functions of such PF spin chains. We also derive a formula which expresses the partition function of any $BC_N$ type of PF spin chain with SAPSRO in terms of partition functions of several $A_K$ type of supersymmetric PF spin chains, where $K\leq N-1$. Subsequently we show that an extended boson-fermion duality relation is obeyed by the partition functions of the $BC_N$ type of PF chains with SAPSRO. Some spectral properties of these spin chains, like level density distribution and nearest neighbour spacing distribution, are also studied.Comment: 36 pages, 2 figures. arXiv admin note: text overlap with arXiv:1402.275

Discrepancy between sub-critical and fast rupture roughness: a cumulant analysis

We study the roughness of a crack interface in a sheet of paper. We distinguish between slow (sub-critical) and fast crack growth regimes. We show that the fracture roughness is different in the two regimes using a new method based on a multifractal formalism recently developed in the turbulence literature. Deviations from monofractality also appear to be different in both regimes

Multi-parameter deformed and nonstandard Y(glM)Y(gl_M) Yangian symmetry in integrable variants of Haldane-Shastry spin chain

By using `anyon like' representations of permutation algebra, which pick up nontrivial phase factors while interchanging the spins of two lattice sites, we construct some integrable variants of Haldane-Shastry (HS) spin chain. Lax equations for these spin chains allow us to find out the related conserved quantities. However, it turns out that such spin chains also possess a few additional conserved quantities which are apparently not derivable from the Lax equations. Identifying these additional conserved quantities, and the usual ones related to Lax equations, with different modes of a monodromy matrix, it is shown that the above mentioned HS like spin chains exhibit multi-parameter deformed and `nonstandard' variants of $Y(gl_M)$ Yangian symmetry.Comment: 18 pages, latex, no figure

Evaluating Product-Centric Continuous Improvements: Impact on Competitive Capabilities and Business Performance

Product-centric continuous improvements (CIs) are actions via which firms modify the design of a product after the start of its production and release into the market. Product-centric CIs are initiated to help build competitive capabilities and sustain competitive advantage throughout the product life cycle. This study complements the perspective pervasive in the extant literature that actions related to product-centric CIs can be disruptive to firms and be associated with negative performance consequences. It investigates a topic that is relatively much less researched, namely the upside potential of product-centric CIs. The empirical analysis is based on data collected from 144 plants in the United States representing process and discrete part manufacturing industries. Specifically, the study analyzes the impact of product-centric CIs on competitive capabilities and business performance. The results of the empirical analysis indicate the following: First, there exist two categories of product-centric CIs: (1) actions for quality improvement and (2) actions for cost reduction. Second, while there is a positive association between each type of CI and the intended competitive capability, there also is a trade-off—i.e., actions for quality improvement increase quality capability but reduce cost capability, and vice versa. Third, there is a strong linkage between business performance and quality capability, but not cost capability. All in all, the study presents empirical evidence that product-centric CIs have a significant impact on competitive capabilities related to quality and cost, and, in turn, have an impact on business performance. From the standpoint of practice, the study suggests that product-centric CIs should be managed to develop competitive capabilities and improve business performance

Nonlinear oscillator with parametric colored noise: some analytical results

The asymptotic behavior of a nonlinear oscillator subject to a multiplicative Ornstein-Uhlenbeck noise is investigated. When the dynamics is expressed in terms of energy-angle coordinates, it is observed that the angle is a fast variable as compared to the energy. Thus, an effective stochastic dynamics for the energy can be derived if the angular variable is averaged out. However, the standard elimination procedure, performed earlier for a Gaussian white noise, fails when the noise is colored because of correlations between the noise and the fast angular variable. We develop here a specific averaging scheme that retains these correlations. This allows us to calculate the probability distribution function (P.D.F.) of the system and to derive the behavior of physical observables in the long time limit

Partially Asymmetric Simple Exclusion Model in the Presence of an Impurity on a Ring

We study a generalized two-species model on a ring. The original model [1] describes ordinary particles hopping exclusively in one direction in the presence of an impurity. The impurity hops with a rate different from that of ordinary particles and can be overtaken by them. Here we let the ordinary particles hop also backward with the rate q. Using Matrix Product Ansatz (MPA), we obtain the relevant quadratic algebra. A finite dimensional representation of this algebra enables us to compute the stationary bulk density of the ordinary particles, as well as the speed of impurity on a set of special surfaces of the parameter space. We will obtain the phase structure of this model in the accessible region and show how the phase structure of the original model is modified. In the infinite-volume limit this model presents a shock in one of its phases.Comment: Adding more references and doing minor corrections, 16 pages and 3 Eps figure

ENHANCEMENT OF BIOAVAILABILITY OF GLIPIZIDE USING SOLID DISPERSIONS WITH GUM AEGLE MARMELOS

Objective: The aim of the proposed study was formulation and in vitro/ vivo evolution   of solid dispersions of glipizide with gum Aegle marmelos. Methods: The phase solubility of glipizide in 0.1N HCl was investigated in the presence of different concentrations of gum Aegle marmelos. The solid dispersions (SDs) of glipizide with gum Aegle marmelos were formulated using solvent evaporation method at ratios of 1:1, 1:2, and 1:5 (glipizide: gum Aegle marmelos). Dissolution studies were conducted. The physicochemical characterization of the formulations was performed by using Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Subsequently, bioavailability of pure glipizide, solid dispersion and marketed product was performed in rat. Results: Glipizide solubility increased as the concentration of gum Aegle marmelos in 0.1N HCl was raised. The solubility study indicates spontaneous drug solubilization, which is supported by negative values of Gibb's free energy (ΔGotr). Glipizide rate of dissolution was increased in SDs containing gum, and the rate increased as the concentration of gum in the SDs increases. After preparing SDs and physical mixtures with gum, the mean dissolution time (MDT) of glipizide decreases considerably. FTIR spectroscopy study revealed that stability and the absence of a well-defined glipizide-gum interaction. The amorphous condition of glipizide in SDs of glipizide with gum was revealed by DSC and XRD studies. Conclusion: The DSC and XRD studies indicate conversion of drug from crystalline to microcrystalline or amorphous form after formulation of solid dispersion with Aegle gum. The solid dispersion of glipizide with Aegle gum (893.04±25.5) showed better therapeutic activity compared to pure glipizide (535.65±11.5) and marketed formulation (767.5±13.6)

Isolation and Purification of C-phycocyanin From Nostoc Muscorum (Cyanophyceae and Cyanobacteria) Exhibits Antimalarial Activity in Vitro

The phycobilin pigments are intensively fluorescent and water soluble. They are categorized into three types, such as pigments containing high, intermediate and low energies are phycoerythrins (phycoerythrocyanins), phycocyanins and allophycocyanins, respectively. Besides light harvesting, the phycobiliproteins have shown industrial and biomedical importance. Among them, C-phycocyanin (C-PC) has been considered to be the most preferred one. The present study was undertaken to evaluate the antimalarial activity of C-PC isolated from a nitrogen-fixing cyanobacterium and Nostoc muscorum. C-PC was extracted and purified by acetone extraction and ammonium sulfate precipitation and dialysis followed by amicon filtration. It was isolated as a~124 kDa water soluble protein molecule. It showed antimalarial activity in vitro against chloroquine sensitive and resistant Plasmodium falciparum strains. Inhibitory concentrations at 50%, 90% and 95% were determined as 10.27±2.79, 53.53±6.26 and 73.78±6.92 µg/ml against the chloroquine-sensitive strains; 10.37±1.43, 56.99±11.07 and 72.79±8.59 µg/ml against chloroquine resistant of Plasmodium falciparum strains. C-PC was found to have antimalarial activity even at a concentration of 3.0µg/ml. The possible mechanism might be relied on the destruction of polymerization of haemozoin by binding of C-PC with ferriprotoporphyrin-IX at the water surface of the plasma membrane

Isolation and Purification of C-phycocyanin From Nostoc Muscorum (Cyanophyceae and Cyanobacteria) Exhibits Antimalarial Activity in Vitro

The phycobilin pigments are intensively fluorescent and water soluble. They are categorized into three types, such as pigments containing high, intermediate and low energies are phycoerythrins (phycoerythrocyanins), phycocyanins and allophycocyanins, respectively. Besides light harvesting, the phycobiliproteins have shown industrial and biomedical importance. Among them, C-phycocyanin (C-PC) has been considered to be the most preferred one. The present study was undertaken to evaluate the antimalarial activity of C-PC isolated from a nitrogen-fixing cyanobacterium and Nostoc muscorum. C-PC was extracted and purified by acetone extraction and ammonium sulfate precipitation and dialysis followed by amicon filtration. It was isolated as a~124 kDa water soluble protein molecule. It showed antimalarial activity in vitro against chloroquine sensitive and resistant Plasmodium falciparum strains. Inhibitory concentrations at 50%, 90% and 95% were determined as 10.27±2.79, 53.53±6.26 and 73.78±6.92 µg/ml against the chloroquine-sensitive strains; 10.37±1.43, 56.99±11.07 and 72.79±8.59 µg/ml against chloroquine resistant of Plasmodium falciparum strains. C-PC was found to have antimalarial activity even at a concentration of 3.0µg/ml. The possible mechanism might be relied on the destruction of polymerization of haemozoin by binding of C-PC with ferriprotoporphyrin-IX at the water surface of the plasma membrane