Lunar Reconnaissance Orbiter: Lessons Learned

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X-ray high-resolution spectroscopy reveals feedback in a Seyfert galaxy from an ultra fast wind with complex ionization and velocity structure

Winds outflowing from Active Galactic Nuclei (AGNs) may carry significant amount of mass and energy out to their host galaxies. In this paper we report the detection of a sub-relativistic outflow observed in the Narrow Line Seyfert 1 Galaxy IRAS17020+4544 as a series of absorption lines corresponding to at least 5 absorption components with an unprecedented wide range of associated column densities and ionization levels and velocities in the range of 23,000-33,000 km/s, detected at X-ray high spectral resolution (E/Delta E ~1000) with the ESA's observatory XMM-Newton. The charge states of the material constituting the wind clearly indicate a range of low to moderate ionization states in the outflowing gas and column densities significantly lower than observed in highly ionized ultra fast outflows. We estimate that at least one of the outflow components may carry sufficient energy to substantially suppress star formation, and heat the gas in the host galaxy. IRAS17020+4544 provides therefore an interesting example of feedback by a moderately luminous AGN hosted in a spiral galaxy, a case barely envisaged in most evolution models, which often predict that feedback processes take place in massive elliptical galaxies hosting luminous quasars in a post merger phase.Comment: 8 pages, 3 figures, to appear on ApJ Letter

Adición de aluminato de estroncio en la elaboración de adoquines de concreto para la mejora en la señalización horizontal de una ciclovía en Lima 2019

El presente trabajo de investigación analiza la factibilidad de la adición de aluminato de estroncio en una relación de 30 por ciento con el peso del material cementante en la elaboración de adoquines de concreto, buscando que estos adoquines de concreto fotoluminiscente cumpla con las especificaciones técnicas estipulas por la Norma española UNE 23035 y la Norma peruana NTP 339.064, esta señalización horizontal fotoluminiscente tendrá como objetivo iluminar la demarcación de una ciclovía ubicada en Lima 2019 con el fin de aportar una señalización horizontal de alta duración e iluminada de manera autónoma en horas nocturnas. Se procedió a realizar el diseño de mezcla para la elaboración de los adoquines de concreto fotoluminiscente obteniendo la cuantificación de los materiales a usar, luego de ello se logró concluir mediante el análisis de artículos científicos sobre la adición de material en la elaboración de bloques de pavimentos que las propiedades físicas y mecánicas del concreto varían pero dentro de los rangos permisibles por las normas citadas basándose a los resultados obtenidos en el laboratorio, sin embargo la relación del aluminato de estroncio en 30 por ciento en peso del material cementante proporciona las iluminancia necesaria para cumplir la normativa española referida a señalización fotoluminiscente.The present research work analyzes the feasibility of adding strontium aluminate in a relationship of 30 percent with the weight of the cementitious material in the manufacture of concrete pavers, seeking that these photoluminescent concrete pavers meet the technical specifications stipulated by The Spanish Norm UNE 23035 and the Peruvian Norm NTP 339.064, this photoluminescent horizontal signaling will aim to illuminate the demarcation of a bicycle path located in Lima 2019 in order to provide a long-lasting and autonomously illuminated horizontal signaling at night. We proceeded to carry out the mix design for the preparation of the photoluminescent concrete paving blocks, obtaining the quantification of the materials to be used, after which it was possible to conclude by analyzing scientific articles on the addition of material in the preparation of pavement blocks that the physical and mechanical properties of concrete vary but within the ranges allowed by the cited standards based on the results obtained in the laboratory, however the ratio of strontium aluminate to 30 weight percent of the cementitious material provides the necessary illuminance to Comply with the Spanish regulations regarding photoluminescent signage

Network science Ising states of matter

Network science provides very powerful tools for extracting information from interacting data. Although recently the unsupervised detection of phases of matter using machine learning has raised significant interest, the full prediction power of network science has not yet been systematically explored in this context. Here we fill this gap by providing an in-depth statistical, combinatorial, geometrical and topological characterization of 2D Ising snapshot networks (IsingNets) extracted from Monte Carlo simulations of the 2D Ising model at different temperatures, going across the phase transition. Our analysis reveals the complex organization properties of IsingNets in both the ferromagnetic and paramagnetic phases and demonstrates the significant deviations of the IsingNets with respect to randomized null models. In particular percolation properties of the IsingNets reflect the existence of the symmetry between configurations with opposite magnetization below the critical temperature and the very compact nature of the two emerging giant clusters revealed by our persistent homology analysis of the IsingNets. Moreover, the IsingNets display a very broad degree distribution and significant degree-degree correlations and weight-degree correlations demonstrating that they encode relevant information present in the configuration space of the 2D Ising model. The geometrical organization of the critical IsingNets is reflected in their spectral properties deviating from the one of the null model. This work reveals the important insights that network science can bring to the characterization of phases of matter. The set of tools described hereby can be applied as well to numerical and experimental data.Comment: 17 pages, 18 figure

Non-parametric learning critical behavior in Ising partition functions: PCA entropy and intrinsic dimension

We provide and critically analyze a framework to learn critical behavior in classical partition functions through the application of non-parametric methods to data sets of thermal configurations. We illustrate our approach in phase transitions in 2D and 3D Ising models. First, we extend previous studies on the intrinsic dimension of 2D partition function data sets, by exploring the effect of volume in 3D Ising data. We find that as opposed to 2D systems for which this quantity has been successfully used in unsupervised characterizations of critical phenomena, in the 3D case its estimation is far more challenging. To circumvent this limitation, we then use the principal component analysis (PCA) entropy, a "Shannon entropy" of the normalized spectrum of the covariance matrix. We find a striking qualitative similarity to the thermodynamic entropy, which the PCA entropy approaches asymptotically. The latter allows us to extract -- through a conventional finite-size scaling analysis with modest lattice sizes -- the critical temperature with less than $1\%$ error for both 2D and 3D models while being computationally efficient. The PCA entropy can readily be applied to characterize correlations and critical phenomena in a huge variety of many-body problems and suggests a (direct) link between easy-to-compute quantities and entropies.Comment: Corrected affiliation informatio

Titanium addition influences antibacterial activity of bioactive glass coatings on metallic implants

© 2017 The Authors In an attempt to combat the possibility of bacterial infection and insufficient bone growth around metallic, surgical implants, bioactive glasses may be employed as coatings. In this work, silica-based and borate-based glass series were synthesized for this purpose and subsequently characterized in terms of antibacterial behavior, solubility and cytotoxicity. Borate-based glasses were found to exhibit significantly superior antibacterial properties and increased solubility compared to their silica-based counterparts, with BRT0 and BRT3 (borate-based glasses with 0 and 15 mol% of titanium dioxide incorporated, respectively) outperforming the remainder of the glasses, both borate and silicate based, in these respects. Atomic Absorption Spectroscopy confirmed the release of zinc ions (Zn2+), which has been linked to the antibacterial abilities of glasses SRT0, BRT0 and BRT3, with inhibition effectively achieved at concentrations lower than 0.7 ppm. In vitro cytotoxicity studies using MC3T3-E1 osteoblasts confirmed that cell proliferation was affected by all glasses in this study, with decreased proliferation attributed to a faster release of sodium ions over calcium ions in both glass series, factor known to slow cell proliferation in vitro

Effect of TiO2 Doping on Degradation Rate, Microstructure and Strength of Borate Bioactive Glass Scaffolds

A titanium-containing borate glass series based on the system (52-X) B2O3–12CaO–6P2O5–14Na2O–16ZnO-XTiO2 with X varying from 0, 5 and 15 mol% of TiO2 incorporated, identified as BRT0, BRT1 and BRT3, respectively, were used in this study. Scaffolds (pore sizes, 165–230 μm and porosity, 53.51–69.51%) were prepared using a polymer foam replication technique. BRT3 scaffolds exhibited higher compressive strength (7.16 ± 0.22 MPa) when compared to BRT0 (6.02 ± 0.47 MPa) and BRT1 (5.65 ± 0.28 MPa) scaffolds with lower, or no, TiO2 content. The solubility of the scaffolds decreased as the TiO2 content increased up to 15 mol% when samples of each scaffold were immersed in DI water and the pH of all these extracts went up from 7.0 to 8.5 in 30 days. The cumulative ion release from the scaffolds showed significant difference with respect to TiO2 content; addition of 5 mol% TiO2 at the expense of borate (B2O3) decreased the ion release remarkably. Furthermore, it was found that for all three scaffolds, cumulative ion release increased with incubation time. The results indicate that the degradation rates and compressive strengths of borate bioactive glass scaffolds could be controlled by varying the amount of TiO2 incorporated, confirming their potential as scaffolds in TKA and rTKA

The role of poly(methyl methacrylate) in management of bone loss and infection in revision total knee arthroplasty: A review

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). Poly(methyl methacrylate) (PMMA) is widely used in joint arthroplasty to secure an implant to the host bone. Complications including fracture, bone loss and infection might cause failure of total knee arthroplasty (TKA), resulting in the need for revision total knee arthroplasty (rTKA). The goals of this paper are: (1) to identify the most common complications, outside of sepsis, arising from the application of PMMA following rTKA, (2) to discuss the current applications and drawbacks of employing PMMA in managing bone loss, (3) to review the role of PMMA in addressing bone infection following complications in rTKA. Papers published between 1970 to 2018 have been considered through searching in Springer, Google Scholar, IEEE Xplore, Engineering village, PubMed and weblinks. This review considers the use of PMMA as both a bone void filler and as a spacer material in two-stage revision. To manage bone loss, PMMA is widely used to fill peripheral bone defects whose depth is less than 5 mm and covers less than 50% of the bone surface. Treatment of bone infections with PMMA is mainly for two-stage rTKA where antibiotic-loaded PMMA is inserted as a spacer. This review also shows that using antibiotic-loaded PMMA might cause complications such as toxicity to surrounding tissue, incomplete antibiotic agent release from the PMMA, roughness and bacterial colonization on the surface of PMMA. Although PMMA is the only commercial bone cement used in rTKA, there are concerns associated with using PMMA following rTKA. More research and clinical studies are needed to address these complications

Characterization of Silica-Based and Borate-Based, Titanium-Containing Bioactive Glasses for Coating Metallic Implants

Bioactive glasses have found applications in diverse fields, including orthopedics and dentistry, where they have been utilized for the fixation of bone and teeth and as scaffolds for drug delivery. The present work outlines the characterization of two novel titanium-containing glass series, one silica-based and one borate-based. For the silica-based series, titanium is added at the expense of silicon dioxide whereas for the borate-based series, it is added at the expense of boron oxide as confirmed by Energy Dispersive Spectroscopy. Amorphous structures are obtained for silica-based glass at 15 mol% TiO2 and for borate-based glasses at 0 mol% and 5 mol%, with low crystal peak intensities exhibited within the remaining glasses. MAS-NMR proves the role of P2O5 as a network modifier for both glass series by evidencing only Q0 structures (and Q1 structures for the silica-based glasses with crystal structures), whereas FTIR proves that Ti acted as a network modifier in the glass as there was an absence of peaks assignable to titanium bonding. This implies that the two glass series will degrade in-situ and release ions at the site of implantation. Additionally, thermal data sourced from these glasses indicate processing windows which make them suitable for enameling onto implants, with the borate-based series exhibiting greater processing windows over the silica-based series, hence making the borate glasses more suitable for coating metallic implants compared to their silica-based counterparts