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The present investigation deals with the facile synthesis and characterization of chitosan (CTS)-based zinc oxide (ZnO) nanoparticles (NPs) and their antimicrobial activities against pathogenic microorganisms. ZnO–CTS NPs were synthesized through two different methods: nano spray drying and precipitation, using various organic compounds (citric acid, glycerol, starch and whey powder) as stabilizers. Both the synthesis methods were simple and were devoid of any chemical usage. The detailed characterization of the NPs was carried out using UV–Vis spectroscopy, dynamic light scattering particle size analysis, zeta potential measurements and scanning electron microscopy, which confirmed the fabrication of NPs with different shapes and sizes. Antimicrobial assay of synthesized ZnO–CTS NPs was carried out against different pathogenic microbial strains (Candida albicans, Micrococcus luteus and Staphylococcus aureus). The significant (p < 0.05) inhibition of growth was observed for both M. luteus and S. aureus with ZnO–CTS NPs (with a concentration ranging from 0.625 to 0.156 mg/ml) as compared to control treatment. ZnO–CTS NPs also showed significant biofilm inhibition activity (p < 0.05) against M. luteus and S. aureus. The study demonstrated the potential of ZnO–CTS NPs as antimicrobial and antibiofilm agents.

There is an ongoing debate on the importance of genetic factors in cancer development, where gene-centered cancer predisposition seems to show that only 5 to 10% of the cancer cases are inheritable. By conducting a systematic analysis of germline genomes of 9712 cancer patients representing 22 common cancer types along with 16,670 noncancer individuals, we identified seven cancer-associated germline genomic patterns (CGGPs), which summarized trinucleotide mutational spectra of germline genomes. A few CGGPs were consistently enriched in the germline genomes of patients whose tumors had smoking signatures or correlated with oncogenesis- and genome instability–related mutations. Furthermore, subgroups defined by the CGGPs were significantly associated with distinct oncogenic pathways, tumor histological subtypes, and prognosis in 13 common cancer types, suggesting that germline genomic patterns enable to inform treatment and clinical outcomes. These results provided evidence that cancer risk and clinical outcomes could be encoded in germline genomes. Germline variants when organized as genomic patterns are associated with cancer risk, oncogenic pathways, and clinical outcomes.

Abstract In this paper, we consider a discrete logistic equation x ( n +1)= x ( n ) exp r ( n ) 1 − x ( n ) K ( n ) where {r(n)} and {K(n)} are positive ω-periodic sequences. Sufficient conditions are obtained for the existence of a positive and globally asymptotically stable ω-periodic solution. Counterexamples are given to illustrate that the conclusions in [1] are incorrect.

Polarization of a vacuum as well as of dispersive and dissipative dielectric media with piece-wise and smooth inhomogeneities is studied with the goal to clarify the question of renormalizability of diverging electromagnetic stress-energy tensor. First, the stress tensor is computed with the Lifshitz approach to London forces in the non-retarded limit, which after the substraction of the leading free space ultraviolet divergencies still retains the divergencies associated with the presence of sharp boundaries between piece-wise inhomogeneities. We call these contributions finite because they become renormalized after a sharp interface is replaced with a dielectric permittivity changing according to a smooth function of spatial coordinates. In addition, such a smoothed out interface exhibits new subleading ultraviolet divergencies that appear due to its internal structure. To systematically deal with the polarization of inhomogeneous media, the Hadamard expansion is applied to single out both finite and subleading contributions and to unequivocally demonstrate incomplete renormalizability of the Lifshitz theory. The above approach also allows us to reveal the nature of surface tension, which proves to be purely quantum mechanical. The deduced theory of surface tension and its calculations for real dielectric media are favorably compared to the available experimental data. While the sharp interface limit recovers the classical boundary conditions for the electric field and uncovers the origin of the apparent local divergencies of the renormalized stresses in the sharp interface formulation previously pointed out in the literature, the problem of surface tension proves to be of a distinguished limit type because the sharp interface formulation loses the information about the internal structure of an interface and hence cannot explain the origin of surface tension. Comment: 62 pages, 7 figures

Real spherical designs and real and complex projective designs have been shown by Delsarte, Goethals, and Seidel to give rise to association schemes when the strength of the design is high compared to its degree as a code. In contrast, designs on the complex unit sphere remain relatively uninvestigated, despite their importance in numerous applications. In this paper we develop the notion of a complex spherical design and show how many such designs carry the structure of an association scheme. In contrast with the real spherical designs and the real and complex projective designs, these association schemes are nonsymmetric. Comment: 45 pages, no figures

A dramatic difference in the ability of the reducing An(III) center in AnCp3 (An=U, Np, Pu; Cp=C5 H5 ) to oxo-bind and reduce the uranyl(VI) dication in the complex [(UO2 )(THF)(H2 L)] (L="Pacman" Schiff-base polypyrrolic macrocycle), is found and explained. These are the first selective functionalizations of the uranyl oxo by another actinide cation. At-first contradictory electronic structural data are explained by combining theory and experiment. Complete one-electron transfer from Cp3 U forms the U(IV) -uranyl(V) compound that behaves as a U(V) -localized single molecule magnet below 4 K. The extent of reduction by the Cp3 Np group upon oxo-coordination is much less, with a Np(III) -uranyl(VI) dative bond assigned. Solution NMR and NIR spectroscopy suggest Np(IV) U(V) but single-crystal X-ray diffraction and SQUID magnetometry suggest a Np(III) -U(VI) assignment. DFT-calculated Hirshfeld charge and spin density analyses suggest half an electron has transferred, and these explain the strongly shifted NMR spectra by spin density contributions at the hydrogen nuclei. The Pu(III) -U(VI) interaction is too weak to be observed in THF solvent, in agreement with calculated predictions.

We study the prime number race for elliptic curves over the function field of a proper, smooth and geometrically connected curve over a finite field. This constitutes a function field analogue of prior work by Mazur, Sarnak and the second author. In this geometric setting we can prove unconditional results whose counterparts in the number field case are conditional on a Riemann Hypothesis and a linear independence hypothesis on the zeros of the implied L-functions. Notably we show that in certain natural families of elliptic curves, the bias generically dissipates as the conductor grows. This is achieved by proving a central limit theorem and combining it with generic linear independence results that will appear in a separate paper. Also we study in detail a particular family of elliptic curves that have been considered by Ulmer. In contrast to the generic case we show that the race exhibits very diverse outcomes, some of which are believed to be impossible in the number field setting. Such behaviors are possible in the function field case because the zeros of Hasse-Weil L-functions for those elliptic curves can be proven to be highly dependent among themselves, which is a very non generic situation.

International audience; The effects of dispatch strategy on electrical performance of amorphous silicon-based solar photovoltaic-thermal systems, Renewable Energy 68, pp. 459-465 (2014). http://dx. Abstract: Previous work has shown that high-temperature short-term spike thermal annealing of hydrogenated amorphous silicon (a-Si:H) photovoltaic thermal (PVT) systems results in higher electrical energy output. The relationship between temperature and performance of a-Si:H PVT is not simple as high temperatures during thermal annealing improves the immediate electrical performance following an anneal, but during the anneal it creates a marked drop in electrical performance. In addition, the power generation of a-Si:H PVT depends on both the environmental conditions and the Staebler-Wronski Effect kinetics. In order to improve the performance of a-Si:H PVT systems further, this paper reports on the effect of various dispatch strategies on system electrical performance. Utilizing experimental results from thermal annealing, an annealing model simulation for a-Si:H-based PVT was developed and applied to different cities in the U. S. to investigate potential geographic effects on the dispatch optimization of the overall electrical PVT systems performance and annual electrical yield. The results showed that spike thermal annealing once per day maximized the improved electrical energy generation.

We propose the existence of an infinite-parameter family of solutions in AdS that oscillate on any number of non-commensurate frequencies. Some of these solutions appear stable when perturbed, and we suggest that they can be used to map out the AdS "islands of stability". By numerically constructing two-frequency solutions and exploring their parameter space, we find that both collapse and non-collapse are generic scenarios near AdS. Unlike other approaches, our results are valid on any timescale and do not rely on perturbation theory.

We express the entropy of a scalar field phi directly in terms of its spacetime correlation function W(x,y) = , assuming that the higher correlators are of "Gaussian" form. The resulting formula associates an entropy S(R) to any spacetime region R; and when R is globally hyperbolic with Cauchy surface Sigma, S(R) can be interpreted as the entropy of the reduced density-matrix belonging to Sigma. One acquires in particular a new expression for the entropy of entanglement across an event-horizon. Thanks to its spacetime character, this expression makes sense in a causal set as well as in a continuum spacetime. Comment: plainTeX, 14 pages, 2 figures. To appear in proceedings of ICGC2011, held Goa, Journal of Physics Conference Series. Most current version is available at http://www.perimeterinstitute.ca/personal/rsorkin/some.papers/ (or wherever my home-page may be, such as http://www.physics.syr.edu/~sorkin/some.papers/)