Cohesion of BaReH9_9 and BaMnH9_9: Density Functional Calculations and Prediction of (MnH9)2−_9)^{2-} Salts

Density functional calculations are used to calculate the structural and electronic properties of BaReH$_9$ and to analyze the bonding in this compound. The high coordination in BaReH$_9$ is due to bonding between Re 5$d$ states and states of $d$-like symmetry formed from combinations of H $s$ orbitals in the H$_9$ cage. This explains the structure of the material, its short bond lengths and other physical properties, such as the high band gap. We compare with results for hypothetical BaMnH$_9$, which we find to have similar bonding and cohesion to the Re compound. This suggests that it may be possible to synthesize (MnH$_9)^{2-}$ salts. Depending on the particular cation, such salts may have exceptionally high hydrogen contents, in excess of 10 weight

MOCDroid: multi-objective evolutionary classifier for Android malware detection

Malware threats are growing, while at the same time, concealment strategies are being used to make them undetectable for current commercial Anti-Virus. Android is one of the target architectures where these problems are specially alarming, due to the wide extension of the platform in different everyday devices.The detection is specially relevant for Android markets in order to ensure that all the software they offer is clean, however, obfuscation has proven to be effective at evading the detection process. In this paper we leverage third-party calls to bypass the effects of these concealment strategies, since they cannot be obfuscated. We combine clustering and multi-objective optimisation to generate a classifier based on specific behaviours defined by 3rd party calls groups. The optimiser ensures that these groups are related to malicious or benign behaviours cleaning any non-discriminative pattern. This tool, named MOCDroid, achieves an ac-curacy of 94.6% in test with 2.12% of false positives with real apps extracted from the wild, overcoming all commercial Anti-Virus engines from VirusTotal

Synthesis and characterization of hybrid organic-inorganic materials based on sulphonated polyamideimide and silica

The preparation of hybrid organic–inorganic membrane materials based on a sulphonated polyamideimide resin and silica filler has been studied. The method allows the sol–gel process to proceed in the presence of a high molecular weight polyamideimide, resulting in well dispersed silica nanoparticles (<50 nm) within the polymer matrix with chemical bonding between the organic and inorganic phases. Tetraethoxysilane (TEOS) was used as the silica precursor and the organosilicate networks were bonded to the polymer matrix via a coupling agent aminopropyltriethoxysilane (APTrEOS). The structure and properties of these hybrid materials were characterized via a range of techniques including FTIR, TGA, DSC, SEM and contact angle analysis. It was found that the compatibility between organic and inorganic phases has been greatly enhanced by the incorporation of APTrEOS. The thermal stability and hydrophilic properties of hybrid materials have also been significantly improved

3D acoustic modelling of dissipative silencers with nonhomogeneous properties and mean flow

A finite element approach is proposed for the acoustic analysis of automotive silencers including a perforated duct with uniform axial mean flow and an outer chamber with heterogeneous absorbent material. This material can be characterized by means of its equivalent acoustic properties, considered coordinate-dependent via the introduction of a heterogeneous bulk density, and the corresponding material airflow resistivity variations. An approach has been implemented to solve the pressure wave equation for a nonmoving heterogeneous medium, associated with the problem of sound propagation in the outer chamber. On the other hand, the governing equation in the central duct has been solved in terms of the acoustic velocity potential considering the presence of a moving medium. The coupling between both regions and the corresponding acoustic fields has been carried out by means of a perforated duct and its acoustic impedance, adapted here to include absorbent material heterogeneities and mean flow effects simultaneously. It has been found that bulk density heterogeneities have a considerable influence on the silencer transmission loss.This work was supported by Ministerio de Economia y Competitividad (Projects DPI2010-15412 and TRA2013-45596-C2-1-R), Conselleria d'Educacio, Cultura i Esport (Project Prometeo/2012/023), and Programa de Apoyo a la Investigacion y Desarrollo (PAID-05-12 and Project SP20120452) of Universitat Politecnica de Valencia.Sánchez Orgaz, EM.; Denia, FD.; Martínez-Casas, J.; Baeza, L. (2014). 3D acoustic modelling of dissipative silencers with nonhomogeneous properties and mean flow. Advances in Mechanical Engineering. 2014(1):1-10. https://doi.org/10.1155/2014/537935S11020141Selamet, A., Xu, M. B., Lee, I. J., & Huff, N. T. (2005). Dissipative expansion chambers with two concentric layers of fibrous material. International Journal of Vehicle Noise and Vibration, 1(3/4), 341. doi:10.1504/ijvnv.2005.007531Selamet, A., Xu, M. B., Lee, I. J., & Huff, N. T. (2006). Effect of voids on the acoustics of perforated dissipative silencers. International Journal of Vehicle Noise and Vibration, 2(4), 357. doi:10.1504/ijvnv.2006.012785Antebas, A. G., Denia, F. D., Pedrosa, A. M., & Fuenmayor, F. J. (2013). A finite element approach for the acoustic modeling of perforated dissipative mufflers with non-homogeneous properties. Mathematical and Computer Modelling, 57(7-8), 1970-1978. doi:10.1016/j.mcm.2012.01.021Peat, K. S., & Rathi, K. L. (1995). A finite element analysis of the convected acoustic wave motion in dissipative silencers. Journal of Sound and Vibration, 184(3), 529-545. doi:10.1006/jsvi.1995.0331Allam, S., & Åbom, M. (2006). Sound propagation in an array of narrow porous channels with application to diesel particulate filters. Journal of Sound and Vibration, 291(3-5), 882-901. doi:10.1016/j.jsv.2005.07.022Allard, J. F., & Atalla, N. (2009). Propagation of Sound in Porous Media. doi:10.1002/9780470747339Montenegro, G., Della Torre, A., Onorati, A., & Fairbrother, R. (2013). A Nonlinear Quasi-3D Approach for the Modeling of Mufflers with Perforated Elements and Sound-Absorbing Material. Advances in Acoustics and Vibration, 2013, 1-10. doi:10.1155/2013/546120Sullivan, J. W., & Crocker, M. J. (1978). Analysis of concentric‐tube resonators having unpartitioned cavities. The Journal of the Acoustical Society of America, 64(1), 207-215. doi:10.1121/1.381963Kirby, R., & Cummings, A. (1998). THE IMPEDANCE OF PERFORATED PLATES SUBJECTED TO GRAZING GAS FLOW AND BACKED BY POROUS MEDIA. Journal of Sound and Vibration, 217(4), 619-636. doi:10.1006/jsvi.1998.1811Lee, I., Selamet, A., & Huff, N. T. (2006). Acoustic impedance of perforations in contact with fibrous material. The Journal of the Acoustical Society of America, 119(5), 2785-2797. doi:10.1121/1.2188354Pierce, A. D. (1990). Wave equation for sound in fluids with unsteady inhomogeneous flow. The Journal of the Acoustical Society of America, 87(6), 2292-2299. doi:10.1121/1.399073Delany, M. E., & Bazley, E. N. (1970). Acoustical properties of fibrous absorbent materials. Applied Acoustics, 3(2), 105-116. doi:10.1016/0003-682x(70)90031-9Lee, I., & Selamet, A. (2012). Measurement of acoustic impedance of perforations in contact with absorbing material in the presence of mean flow. Noise Control Engineering Journal, 60(3), 258-266. doi:10.3397/1.3701003Kirby, R., & Denia, F. D. (2007). Analytic mode matching for a circular dissipative silencer containing mean flow and a perforated pipe. The Journal of the Acoustical Society of America, 122(6), 3471-3482. doi:10.1121/1.2793614Selamet, A., Xu, M. B., Lee, I.-J., & Huff, N. T. (2004). Analytical approach for sound attenuation in perforated dissipative silencers. The Journal of the Acoustical Society of America, 115(5), 2091-2099. doi:10.1121/1.1694994Denia, F. D., Selamet, A., Fuenmayor, F. J., & Kirby, R. (2007). Acoustic attenuation performance of perforated dissipative mufflers with empty inlet/outlet extensions. Journal of Sound and Vibration, 302(4-5), 1000-1017. doi:10.1016/j.jsv.2007.01.005Denia, F. D., Antebas, A. G., Selamet, A., & Pedrosa, A. M. (2011). Acoustic characteristics of circular dissipative reversing chamber mufflers. Noise Control Engineering Journal, 59(3), 234. doi:10.3397/1.3560904Kirby, R., & Cummings, A. (1999). Prediction of the bulk acoustic properties of fibrous materials at low frequencies1A shorter version of this paper was presented at the EuroNoise Conference, Lyon, France, 21-23 March 19951. Applied Acoustics, 56(2), 101-125. doi:10.1016/s0003-682x(98)00015-2Selamet, A., Lee, I. ., & Huff, N. . (2003). Acoustic attenuation of hybrid silencers. Journal of Sound and Vibration, 262(3), 509-527. doi:10.1016/s0022-460x(03)00109-3Payri, F., Broatch, A., Salavert, J. M., & Moreno, D. (2010). Acoustic response of fibrous absorbent materials to impulsive transient excitations. Journal of Sound and Vibration, 329(7), 880-892. doi:10.1016/j.jsv.2009.10.015Lee, S.-H., & Ih, J.-G. (2003). Empirical model of the acoustic impedance of a circular orifice in grazing mean flow. The Journal of the Acoustical Society of America, 114(1), 98-113. doi:10.1121/1.158128

Vitamin D receptor ChIP-seq in primary CD4+ cells: relationship to serum 25-hydroxyvitamin D levels and autoimmune disease

PMCID: PMC3710212This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Hypoxia Negatively Regulates Antimetastatic PEDF in Melanoma Cells by a Hypoxia Inducible Factor-Independent, Autophagy Dependent Mechanism

Pigment epithelium-derived factor (PEDF), a member of the serine protease inhibitor (SERPIN) superfamily, displays a potent antiangiogenic and antimetastatic activity in a broad range of tumor types. Melanocytes and low aggressive melanoma cells secrete high levels of PEDF, while its expression is lost in highly aggressive melanomas. PEDF efficiently abrogates a number of functional properties critical for the acquisition of metastatic ability by melanoma cells, such as neovascularization, proliferation, migration, invasiveness and extravasation. In this study, we identify hypoxia as a relevant negative regulator of PEDF in melanocytes and low aggressive melanoma cells. PEDF was regulated at the protein level. Importantly, although downregulation of PEDF was induced by inhibition of 2-oxoglutarate-dependent dioxygenases, it was independent of the hypoxia inducible factor (HIF), a key mediator of the adaptation to hypoxia. Decreased PEDF protein was not mediated by inhibition of translation through untranslated regions (UTRs) in melanoma cells. Degradation by metalloproteinases, implicated on PEDF degradation in retinal pigment epithelial cells, or by the proteasome, was also excluded as regulatory mechanism in melanoma cells. Instead, we found that degradation by autophagy was critical for PEDF downregulation under hypoxia in human melanoma cells. Our findings show that hypoxic conditions encountered during primary melanoma growth downregulate antiangiogenic and antimetastasic PEDF by a posttranslational mechanism involving degradation by autophagy and could therefore contribute to the acquisition of highly metastatic potential characteristic of aggressive melanoma cells

A Bayesian assessment of an approximate model for unconfined water flow in sloping layered porous media

The prediction of water table height in unconfined layered porous media is a difficult modelling problem that typically requires numerical simulation. This paper proposes an analytical model to approximate the exact solution based on a steady-state Dupuit–Forchheimer analysis. The key contribution in relation to a similar model in the literature relies in the ability of the proposed model to consider more than two layers with different thicknesses and slopes, so that the existing model becomes a special case of the proposed model herein. In addition, a model assessment methodology based on the Bayesian inverse problem is proposed to efficiently identify the values of the physical parameters for which the proposed model is accurate when compared against a reference model given by MODFLOW-NWT, the open-source finite-difference code by the U.S. Geological Survey. Based on numerical results for a representative case study, the ratio of vertical recharge rate to hydraulic conductivity emerges as a key parameter in terms of model accuracy so that, when appropriately bounded, both the proposed model and MODFLOW-NWT provide almost identical results

Identification of a gene signature for discriminating metastatic from primary melanoma using a molecular interaction network approach

Understanding the biological factors that are characteristic of metastasis in melanoma remains a key approach to improving treatment. In this study, we seek to identify a gene signature of metastatic melanoma. We configured a new network-based computational pipeline, combined with a machine learning method, to mine publicly available transcriptomic data from melanoma patient samples. Our method is unbiased and scans a genome-wide protein-protein interaction network using a novel formulation for network scoring. Using this, we identify the most influential, differentially expressed nodes in metastatic as compared to primary melanoma. We evaluated the shortlisted genes by a machine learning method to rank them by their discriminatory capacities. From this, we identified a panel of 6 genes, ALDH1A1, HSP90AB1, KIT, KRT16, SPRR3 and TMEM45B whose expression values discriminated metastatic from primary melanoma (87% classification accuracy). In an independent transcriptomic data set derived from 703 primary melanomas, we showed that all six genes were significant in predicting melanoma specific survival (MSS) in a univariate analysis, which was also consistent with AJCC staging. Further, 3 of these genes, HSP90AB1, SPRR3 and KRT16 remained significant predictors of MSS in a joint analysis (HR = 2.3, P = 0.03) although, HSP90AB1 (HR = 1.9, P = 2 × 10−4) alone remained predictive after adjusting for clinical predictors