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This paper proposes a transition from monofractal to multifractal topology to study the dynamic behavior of modern power networks. For this purpose, a multifractal power network is proposed based on the two scales Cantor set topology. The dynamic properties of the proposed network are investigated using the renormalization method, Continuous Wavelet Transform (CWT) and Multifractal Detrended Fluctuation Analysis (MFDFA). Our findings prove that the scale-invariant behavior of the proposed network is governed by two scales factors. The results of CWT indicate that the frequency responses corresponding to the two scales Cantor network exhibit a self-similar behavior. As for the MFDFA results, they revealed that a set of fractal dimensions is required to reproduce the dynamics of the proposed multifractal network. [ABSTRACT FROM AUTHOR]

This paper investigates the scale invariance of power networks with respect to the distributed nature of transmission lines. The frequency responses corresponding to Sierpinski and Cantor networks are underlined with lumped and distributed parameters models. The range of validity of scale invariance is investigated for both lumped and distributed parameters networks. The effect of scale invariance on the frequency response of power system is traduced by a power law at intermediate frequencies for lumped networks. For a distributed network, the resonant behavior extends to high frequency. Application to real networks is also proposed. Copyright © 2018 Praise Worthy Prize S.r.l. - All rights reserved. [ABSTRACT FROM AUTHOR]

Parameterized equations have been derived using variational calculation for energy levels of Wannier excitons in 2D-parabolic quantum wells in uniform electric and magnetic fields. The formulation has been performed in the framework of the effective mass approximation and two-band model. Illustrations have been given for GaAlAs-GaAs-GaAlAs and CdMnTe-CdTe-CdMnTe parabolic quantum wells. The comparison with existing data displays good agreement. [ABSTRACT FROM AUTHOR]

The electric polarizability α of ionized-donor-bound exciton D+X in bulk semiconductor is calculated for all values of the effective electron-to-hole mass ratio σ included in the range of stability (σ<σx). The calculation is performed within the variational method by using 56-term wave function. An asymptotic behavior of α in the vicinity of the critical value σc is deduced. We have also calculated the limiting value σ for which the polarizability equals that of D- system. [ABSTRACT FROM AUTHOR]

A set of analytic equations for calculating the binding energies of excitons in T-shaped and squared quantum well wires are established within the effective mass approximation and the two-band model. The resolution is performed in the framework of the variational method. The projections of the relative movement in a lateral plane (2D exciton) and along the free movement direction (1D exciton) are examined as limiting cases. Binding energies and spatial extensions of the exciton as functions of the size of the wire for both the ground and the first excited states are calculated in the case of GaAs/GaAlAs heterostructures for T-shaped and squared geometries. The method is applied to calculate the effects on the excitons induced by the application of crossed electric and magnetic fields. Comparison between quantum wells, T-wires and squared wires is given. [ABSTRACT FROM AUTHOR]

A number of studies have focused on the beneficial properties of Curcumin (diferuloyl methane, used in South Asian cuisine and traditional medicine) such as the chemoprevention of cancer. Recent studies have also indicated that this material has significant benefits for the treatment of cancer and is currently undergoing several clinical trials. We have been interested in the application of this compound as a therapeutic agent for advanced prostate cancer, particularly the skeletal complications in this malignancy. Our earlier work indicated that this compound could inhibit the osteomimetic properties which occur in castration resistant prostate cancer cells, by interfering with the common denominators between these cancer cells and the bone cells in the metastatic tumor microenvironment, namely the osteoblasts and the osteoclast. We predicted that curcumin could break the vicious cycle of reciprocal stimulation that results in uncontrolled osteolysis in the bony matrix. In this work, we have evaluated the potential of this compound in inhibiting the bone metastasis of hormone refractory prostate cancer cells in an established animal model. Our results strongly suggest that curcumin modulates the TGF- β signaling that occurs due to bone matrix degradation by up-regulating the metastasis inhibitory bone morphogenic protein-7 (BMP- 7). This enhancement of BMP-7 in the context of TGF- β in the tumor microenvironment is shown to enhance the mesenchymal-to-epithelial transition. Most importantly, we show that as a result of BMP-7 up-regulation, a novel brown/beige adipogenic differentiation program is also up-regu- lated which plays a role in the inhibition of bone metastasis. Our results suggest that curcumin may subvert the TGF- β signaling to an alternative adipogenic differentiation program in addition to the previously established interference with the osteomimetic properties, thus inhibiting the bone metastatic processes in a chemopreventive as well as therapeutic setting.

The 'vanishing bone' or inherited osteolysis/arthritis syndromes represent a heterogeneous group of skeletal disorders characterized by mineralization defects of affected bones and joints. Differing in anatomical distribution, severity and associated syndromic features, gene identification in each 'vanishing bone' disorder should provide unique insights into genetic/molecular pathways contributing to the overall control of skeletal growth and development. We previously described and then demonstrated that the novel autosomal recessive osteolysis/arthritis syndrome, multicentric osteolysis with arthritis (MOA) (MIM #605156), was caused by inactivating mutations in the MMP2 gene [Al Aqeel, A., Al Sewairi, W., Edress, B., Gorlin, R.J., Desnick, R.J. and Martignetti, J.A. (2000) Inherited multicentric osteolysis with arthritis: A variant resembling Torg syndrome in a Saudi family. Am. J. Med. Genet., 93, 11-18.]. These in vivo results were counterintuitive and unexpected since previous in vitro studies suggested that MMP-2 overexpression and increased activity, not deficiency, would result in the bone and joint features of MOA. The apparent lack of a murine model [Itoh, T., Ikeda, T., Gomi, H., Nakao, S., Suzuki, T. and Itohara, S. (1997) Unaltered secretion of beta-amyloid precursor protein in gelatinase A (matrix metalloproteinase 2)-deficient mice. J. Biol. Chem., 272, 22389-22392.] has hindered studies on disease pathogenesis and, more fundamentally, in addressing the paradox of how functional loss of a single proteolytic enzyme results in an apparent increase in bone loss. Here, we report that Mmp2-/- mice display attenuated features of human MOA including progressive loss of bone mineral density, articular cartilage destruction and abnormal long bone and craniofacial development. Moreover, these changes are associated with markedly and developmentally restricted decreases in osteoblast and osteoclast numbers in vivo. Mmp2-/- mice have approximately 50% fewer osteoblasts and osteoclasts than control littermates at 4 days of life but these differences have nearly resolved by 4 weeks of age. In addition, despite normal cell numbers in vivo at 8 weeks of life, Mmp2-/- bone marrow cells are unable to effectively support osteoblast and osteoclast growth and differentiation in culture. Targeted inhibition of MMP-2 using siRNA in human SaOS2 and murine MC3T3 osteoblast cell lines resulted in decreased cell proliferation rates. Taken together, our findings suggest that MMP-2 plays a direct role in early skeletal development and bone cell growth and proliferation. Thus, Mmp2-/- mice provide a valuable biological resource for studying the pathophysiological mechanisms underlying the human disease and defining the in vivo physiological role of MMP-2.