Efficiency of letrozole loaded PLGA nanoparticles on sex reversal of Poecilia reticulata (Peters, 1859)

Males of Poecilia reticulata showed extreme diversity in color, particularly of their fins, while the females lack the bright colors and are largely whitish. Such extreme variability of color and finnage lead to demand of males in the markets. The aim of present work was to develop a new Letrozole (LTZ)-loaded PLGA nanoparticles for effective delivery of the masculinization drug, letrozole, as an alternative to commercially available masculinization agents. The LTZ-loaded PLGA NPs were prepared by solvent displacement technique. The particle size of LTZ-loaded PLGA NPs was analyzed using LICOMP particle size analyzer and was found to be in the range of 72 nm to 520 nm with average size of 221.5±63.3 nm. Zeta potential was estimated to be about 21.35 mV with loading efficiency of 43.63±4.63 %. In the present study, a series of experiments were carried out to induce masculinization using LTZ-loaded PLGA nanoparticles during the sex differentiation period. Guppy (P. reticulate) fry were treated with LTZ-loaded PLGA nanoparticles at dosages 5, 25, 50 and 100 ppm/kg diet for 10, 15 and 30 days. The gonopodium index and GSI showed increasing order in male and female respectively with dose of LTZ-loaded nanoparticles. The results indicated an increase in the proportion of males with dosage and duration of treatment. This has been done for the first time using nanotechnology efficiently which has shown an increase in the male population of Poecilia reticulata with lesser dose of nano-encapsulated Letrozole (LTZ)-loaded PLGA nanoparticles drug as compared with naked control Letrozole (LTZ) drug delivery

Flux melting in BSCCO: Incorporating both electromagnetic and Josephson couplings

Multilevel Monte Carlo simulations of a BSCCO system are carried out including both Josephson as well as electromagnetic couplings for a range of anisotropies. A first order melting transition of the flux lattice is seen on increasing the temperature and/or the magnetic field. The phase diagram for BSCCO is obtained for different values of the anisotropy parameter $\gamma$. The best fit to the experimental results of D. Majer {\it et al.} [Phys. Rev. Lett. {\bf 75}, 1166 (1995)] is obtained for $\gamma\approx 250$ provided one assumes a temperature dependence $\lambda^2(0)/\lambda^2(T)=1-t$ of the penetration depth with $t=T/T_c$. Assuming a dependence $\lambda^2(0)/\lambda^2(T)=1-t^2$ the best fit is obtained for $\gamma\approx 450$. For finite anisotropy the data is shown to collapse on a straight line when plotted in dimensionless units which shows that the melting transition can be satisfied with a single Lindemann parameter whose value is about 0.3. A different scaling applies to the $\gamma=\infty$ case. The energy jump is measured across the transition and for large values of $\gamma$ it is found to increase with increasing anisotropy and to decrease with increasing magnetic field. For infinite anisotropy we see a 2D behavior of flux droplets with a transition taking place at a temperature independent of the magnetic field. We also show that for smaller values of anisotropy it is reasonable to replace the electromagnetic coupling with an in-plane interaction represented by a Bessel function of the second kind ($K_0$), thus justifying our claim in a previous paper.Comment: 12 figures, revtex

Epidemiology of type 2 diabetes: Indian scenario.

India leads the world with largest number of diabetic subjects earning the dubious distinction of being termed the "diabetes capital of the world". According to the Diabetes Atlas 2006 published by the International Diabetes Federation, the number of people with diabetes in India currently around 40.9 million is expected to rise to 69.9 million by 2025 unless urgent preventive steps are taken. The so called "Asian Indian Phenotype" refers to certain unique clinical and biochemical abnormalities in Indians which include increased insulin resistance, greater abdominal adiposity i.e., higher waist circumference despite lower body mass index, lower adiponectin and higher high sensitive C-reactive protein levels. This phenotype makes Asian Indians more prone to diabetes and premature coronary artery disease. At least a part of this is due to genetic factors. However, the primary driver of the epidemic of diabetes is the rapid epidemiological transition associated with changes in dietary patterns and decreased physical activity as evident from the higher prevalence of diabetes in the urban population. Even though the prevalence of microvascular complications of diabetes like retinopathy and nephropathy are comparatively lower in Indians, the prevalence of premature coronary artery disease is much higher in Indians compared to other ethnic groups. The most disturbing trend is the shift in age of onset of diabetes to a younger age in the recent years. This could have long lasting adverse effects on nation's health and economy. Early identification of at-risk individuals using simple screening tools like the Indian Diabetes Risk Score (IDRS) and appropriate lifestyle intervention would greatly help in preventing or postponing the onset of diabetes and thus reducing the burden on the community and the nation as a whole

Study of Phytochemical, Antioxidant, Antimicrobial and Anticancer Activity of Berberis Aristata.

The present study was undertaken to find the phytochemical presence, antioxidant potential, antimicrobial activity, and anticancer activity of methanol extract of Berberis Aristata. Plant extract showed the presence of antioxidants like alkaloid, saponin, terpenoids, coumarin, flavonoids, tannin, glycoside and steroid. Further, antioxidant assay like DPPH (Diphenyl-2-picrylhydrazyl) assay, hydrogen peroxide assay and reducing power assay was done. DPPH free radical Scavenging Activity was expressed in % inhibition with L Ascorbic acid as standard showing IC50 9.6μg/ml and that of extract was 33.31μg/ml. Hydrogen peroxide radical scavenging activity was comparable to standard, IC50 for L Ascorbic acid is 54.23g/ml and that of B Aristata is 60.6g/ml. Similarly, reducing power of plant extract at different concentration was comparable with L-Ascorbic Acid. Antimicrobial screening showed good positive result with Candida Albicans, Salmonella typhii, Pseudomonas aeruginosa and Escherichia coli. Cell viability assay; MTT; showed a significant cytotoxicity to MDA-MB-231 and U-87 MG human cancer cell line compared to NIH/3T3 standard embryonic fibroblast cell lines of mouse

The chromatic discrepancy of graphs

For a proper vertex coloring cc of a graph GG, let φc(G)φc(G) denote the maximum, over all induced subgraphs HH of GG, the difference between the chromatic number χ(H)χ(H) and the number of colors used by cc to color HH. We define the chromatic discrepancy of a graph GG, denoted by φ(G)φ(G), to be the minimum φc(G)φc(G), over all proper colorings cc of GG. If HH is restricted to only connected induced subgraphs, we denote the corresponding parameter by View the MathML sourceφˆ(G). These parameters are aimed at studying graph colorings that use as few colors as possible in a graph and all its induced subgraphs. We study the parameters φ(G)φ(G) and View the MathML sourceφˆ(G) and obtain bounds on them. We obtain general bounds, as well as bounds for certain special classes of graphs including random graphs. We provide structural characterizations of graphs with φ(G)=0φ(G)=0 and graphs with View the MathML sourceφˆ(G)=0. We also show that computing these parameters is NP-hard

Wave attenuation model for dephasing and measurement of conditional times

Inelastic scattering induces dephasing in mesoscopic systems. An analysis of previous models to simulate inelastic scattering in such systems is presented and also a relatively new model based on wave attenuation is introduced. The problem of Aharonov-Bohm(AB) oscillations in conductance of a mesoscopic ring is studied. We have shown that conductance is symmetric under flux reversal and visibility of AB oscillations decay to zero as function of the incoherence parameter, signalling dephasing. Further wave attenuation is applied to a fundamental problem in quantum mechanics, i.e., the conditional(reflection/transmission) times spent in a given region of space by a quantum particle before scattering off from that region.Comment: 8 pages, 6 figures. Based on presentations by A. M. J and C. B at the 2nd Winter Institute on Foundations of Quantum theory, Quantum Optics and QIP held at S N Bose National Centre for Basic Sciences, Kolkata, India, from January 2-11, 200

Parallelizing Deadlock Resolution in Symbolic Synthesis of Distributed Programs

Previous work has shown that there are two major complexity barriers in the synthesis of fault-tolerant distributed programs: (1) generation of fault-span, the set of states reachable in the presence of faults, and (2) resolving deadlock states, from where the program has no outgoing transitions. Of these, the former closely resembles with model checking and, hence, techniques for efficient verification are directly applicable to it. Hence, we focus on expediting the latter with the use of multi-core technology. We present two approaches for parallelization by considering different design choices. The first approach is based on the computation of equivalence classes of program transitions (called group computation) that are needed due to the issue of distribution (i.e., inability of processes to atomically read and write all program variables). We show that in most cases the speedup of this approach is close to the ideal speedup and in some cases it is superlinear. The second approach uses traditional technique of partitioning deadlock states among multiple threads. However, our experiments show that the speedup for this approach is small. Consequently, our analysis demonstrates that a simple approach of parallelizing the group computation is likely to be the effective method for using multi-core computing in the context of deadlock resolution

Jet Breaks in Short Gamma-Ray Bursts. I: The Uncollimated Afterglow of GRB 050724

We report the results of the \chandra observations of the \swift-discovered short Gamma-Ray Burst GRB 050724. \chandra observed this burst twice, about two days after the burst and a second time three weeks later. The first \chandra pointing occurred at the end of a strong late-time flare. About 150 photons were detected during this 49.3 ks observation in the 0.4-10.0 keV range. The spectral fit is in good agreement with spectral analysis of earlier \swift XRT data. In the second \chandra pointing the afterglow was clearly detected with 8 background-subtracted photons in 44.6 ks. From the combined \swift XRT and \chandra-ACIS-S light curve we find significant flaring superposed on an underlying power-law decay slope of $\alpha$=0.98$^{+0.11}_{-0.09}$. There is no evidence for a break between about 1 ks after the burst and the last \chandra pointing about three weeks after the burst. The non-detection of a jet break places a lower limit of 25$^{\circ}$ on the jet opening angle, indicating that the outflow is less strongly collimated than most previously-reported long GRBs. This implies that the beaming corrected energy of GRB 050724 is at least $4\times 10^{49}$ ergs.Comment: 7 pages, ApJ acceped, scheduled for December 20, 2006, ApJ, 65

Aharonov-Bohm oscillations and spin transport in a mesoscopic ring with a magnetic impurity

We present a detailed analysis of the Aharonov-Bohm (AB) interference oscillations manifested through transmission of an electron in a mesoscopic ring with a magnetic impurity atom inserted in one of its arms. The spin polarization transport is also studied. The electron interacts with the impurity through the exchange interaction leading to exchange spin-flip scattering. Transmission in the spin-flipped and spin-unflipped channels are explicitly calculated. We show that the entanglement between electron and spin-flipper states lead to a reduction of AB oscillations in spite of absence of any inelastic scattering. The spin-conductance (related to spin-polarized transmission coefficient) is asymmetric in the flux reversal as opposed to the two probe conductance which is symmetric under flux reversal. We point out certain limitations of this model in regard to the general notion of dephasing in quantum mechanics.Comment: 6 pages RevTeX, 9 eps figures included, enlarged version of cond-mat/000741