bluuebunny/crossref_metadata_2025_split huggingface dataset:
Even Simpler Modeling of Quadruply Lensed Quasars (and Random Quartets) Using Witt's Hyperbola
Authors: Schechter Paul L. , Wynne Raymond A. 
Published: April 2019

Abstract
Witt (1996) has shown that, for an elliptical potential, the four images of a quadruply lensed quasar lie on a rectangular hyperbola that passes through the unlensed quasar position and the center of the potential as well. Wynne & Schechter (2018) have shown that, for the singular isothermal elliptical potential (SIEP), the four images also lie on an “amplitude” ellipse centered on the quasar position with axes parallel to the hyperbola’s asymptotes. Witt’s hyperbola arises from equating the directions of both sides of the lens equation. The amplitude ellipse derives from equating the magnitudes. One can model any four points as an SIEP in three steps. (1) Find the rectangular hyperbola that passes through the points. (2) Find the aligned ellipse that also passes through them. (3) Find the hyperbola with asymptotes parallel to those of the first that passes through the center of the ellipse and the pair of images closest to each other. The second hyperbola and the ellipse give an SIEP that predicts the positions of the two remaining images where the curves intersect. Pinning the model to the closest pair guarantees a four-image model. Such models permit rapid discrimination between gravitationally lensed quasars and random quartets of stars.
An Analytical Model of Radial Dust Trapping in Protoplanetary Disks
Authors: Sierra Anibal , Lizano Susana , Macías Enrique , Carrasco-González Carlos , Osorio Mayra , Flock Mario 
Published: April 2019

Abstract
We study dust concentration in axisymmetric gas rings in protoplanetary disks. Given the gas surface density, we derived an analytical total dust surface density by taking into account the differential concentration of all grain sizes. This model allows us to predict the local dust-to-gas mass ratio and the slope of the particle size distribution, as a function of radius. We test this analytical model by comparing it with a 3D magnetohydrodynamical simulation of dust evolution in an accretion disk. The model is also applied to the disk around HD 169142. By fitting the disk continuum observations simultaneously at λ = 0.87, 1.3, and 3.0 mm, we obtain a global dust-to-gas mass ratio

and a viscosity coefficient α = 1.35 × 10−2. This model can be easily implemented in numerical simulations of accretion disks.
On the Dynamical Relevance of Galaxy Spiral Arm Evolution. I. Arm Density Structure
Authors: Mata-Chávez M. Dolores , Velázquez Héctor , Pichardo Barbara , Valenzuela Octavio , Roca-Fábrega Santi , Hernández-Toledo Héctor , Aquino-Ortíz Erik 
Published: April 2019

Abstract
We explore the spiral arm structural properties in a large variety of simulated galaxy systems. We study spiral arms arising from isolated barred and unbarred galaxies, as well as from interactions with small satellites. In all these first models, galactic systems are all embedded in a spherical dark matter halo. We also study spiral arms arising from a galactic system embedded in a triaxial dark matter halo. Simulations used in this work have been obtained by using different N-body codes and initial conditions techniques. Our strategy is to study the 3D arm structure through the analysis of pitch angle, along/transverse/vertical density laws and their corresponding scale lengths, and spiral lifetime. Our main results are as follows. First, the radial density profile of all spiral arms analyzed in this work is exponential. This profile resembles the one of the disk but with a scale length that is systematically larger (5%–40%). This result suggests that spiral arm gravitational influence is important beyond the scale radius of the disk. Second, the vertical and transversal density laws of the spiral arms follow a sech2. The vertical scale length is compatible with the one of the disk; this is observed in all spiral arms analyzed here, independently of their origin, i.e., bar, high-order disk perturbation, tidal interaction with satellites, or halo triaxiality. Third, in the triaxial and satellite simulations, spiral arms follow a logarithmic locus all through their lifetime; the remaining models develop transient, recurrent, and short-lived spirals with a nondefined locus. In all cases, spiral arms wind up in their lifetime with a small pitch angle reduction. It is common that newborn spirals inherit the pitch angle of the previous ones; this result challenges the dynamical relevance of arm evolution. Finally, from the analysis of public photometric observations of NGC 2543, we state that the properties of observed spiral arm structure can be consistent with our conclusions. Further and systematic comparisons with observations are needed in order to confirm our results.
Participatory audiences in the European public service media: Content production and copyright
Authors: López-Cepeda Ana-María , López-Golán Mónica , Rodríguez-Castro Marta 
Published: April 2019

The interactivity and participation of the public in the media is not a novelty, but has increased significantly with the adaptation to the digital convergence process. The possibility for audiences to share content through social platforms or generating its own is raising new ethical and legal issues. In this context, the public service audiovisual media must be pioneer both in the introduction of new participatory experiences and in the debate on the behaviour of the media regarding the interaction with its users. The objective of this article is twofold: on the one hand, to approach the current scenario of participatory mechanisms present in the European public service audiovisual media; on the other hand, to determine how this media is solving the new problems generated by the increase in user interaction. The research on participatory mechanisms offered by public service media shows that social networks, blogs, and comment sections are the main tools for discursive participation, while the field of creative participation requires the exploitation of new innovation strategies. The main challenge arising from this situation is how to control the legality of user-generated content and how to manage the ownership of copyright according to social values represented in public service media.
La interactividad y participación del público en los medios de comunicación no supone una novedad, pero se ha incrementado notablemente con la adaptación al proceso de convergencia digital. La posibilidad de las audiencias de compartir a través de plataformas sociales o de generar contenido propio está planteando nuevas problemáticas éticas y jurídicas. En este contexto, los medios audiovisuales de servicio público deben ser pioneros tanto en la introducción de nuevas experiencias participativas como en el debate sobre el comportamiento de los medios en la relación con sus usuarios. El objetivo de este artículo es doble: por un lado, hacer una aproximación al panorama actual de los mecanismos de participación con los que cuenta el servicio audiovisual público europeo; por otro, conocer cómo estos medios están resolviendo las nuevas problemáticas generadas por el incremento en las relaciones con los usuarios. La exploración de los mecanismos de participación ofrecidos por los medios de comunicación públicos demuestra que las redes sociales, los blogs y las secciones de comentarios son los instrumentos de participación discursiva predominantes, mientras que en la esfera de la participación creativa es necesario explotar nuevas estrategias de innovación. Como principal reto a abordar, se plantea cómo controlar la legalidad del contenido generado por los usuarios y gestionar la titularidad de los derechos de autor conforme a los valores sociales representados en los medios públicos.
D’un service transversal prestataire de services à une UFR décisionnaire de la politique des langues : exemple concret de la structuration d’une UFR Lansad à l'université de Lorraine et de ses impacts en termes de recherche et formations
Authors: Molle Nicolas , Paris Justine , Martin Carine 
Published: April 2019

Comme de nombreux articles le soulignent, il n’y pas de politique des langues réellement concertée dans le secteur des Langues pour spécialistes d’autres disciplines (Lansad, Braud et al. ; Brudermann et al. ; Commission Formations de la SAES ; Petit). Ce secteur revêt une multitude de formes et de structures disparates au sein des établissements français, entraînant un manque de reconnaissance institutionnelle. Depuis 2014, l’université de Lorraine s’attache à y remédier à travers son unité de formation et de recherche Lansad (UFR Lansad) – fruit d’une expertise didactique qui a su convaincre les instances politiques de l’université. Cette UFR est aujourd’hui un décideur majeur de la politique de l’enseignement des langues de son université. Cet article s’attache à montrer comment ce modèle a créé un essaimage de formations innovantes inspirées par les travaux de l’équipe de recherche Didactique des Langues et Sociolinguistique (Crapel) et comment sa reconnaissance témoigne de la nécessité de favoriser un lien fort entre recherche et formations.
Büchi’s Problem in Modular Arithmetic for Arbitrary Quadratic Polynomials
Authors: Sáez Pablo , Vidaux Xavier , Vsemirnov Maxim 
Published: April 2019

AbstractGiven a prime $p\geqslant 5$ and an integer $s\geqslant 1$, we show that there exists an integer $M$ such that for any quadratic polynomial $f$ with coefficients in the ring of integers modulo $p^{s}$, such that $f$ is not a square, if a sequence $(f(1),\ldots ,f(N))$ is a sequence of squares, then $N$ is at most $M$. We also provide some explicit formulas for the optimal $M$.
Occupational Therapy Intervention to Improve Outcomes Among Frail Older Adults: A Scoping Review
Authors: Fritz Heather , Seidarabi Sara , Barbour Ryan , Vonbehren Alexandra 
Published: April 2019

Abstract
Importance: Frailty is common in later life and increases older adults’ risk for early disability, institutionalization, and mortality.
Objective: To explore the research literature on occupational therapy interventions to improve outcomes among frail, community-dwelling older adults.
Design: Scoping review of the peer-reviewed literature about occupational therapy interventions and frailty published between January 1996 and January 2017.
Results: Ten studies met the inclusion criteria. The majority of the studies focused on adults age 65 yr or older, operationalized frailty as activities of daily living disability, and did not use validated frailty measures to identify frail older adults. Interventions were delivered both as a stand-alone intervention and as part of a multidisciplinary approach. Treatments focused on recommendations and training in use of adaptive devices or assistive technologies, performance of self-care, and recommendations for home modifications.
Conclusion: Additional research is warranted to build the evidence base and better inform the design and selection of occupational therapy interventions to improve outcomes among frail older adults.
A combination of curcumin, vorinostat and silibinin reverses Aβ-induced nerve cell toxicity via activation of AKT-MDM2-p53 pathway
Authors: Meng Jia , Li Yan , Zhang Mingming , Li Wenjing , Zhou Lin , Wang Qiujun , Lin Lin , Jiang Lihong , Zhu Wenliang 
Published: April 2019

Alzheimer’s disease (AD) is a significant health issue for the elderly and becoming increasingly common as the global population ages. Although many efforts have been made to elucidate its pathology, there is still a lack of effective clinical anti-AD agents. Previous research has shown the neuroprotective properties of a combination of curcumin and vorinostat. In this study, nine other neuroprotective agents were investigated to examine whether a three-drug combination of curcumin, vorinostat, and a new drug is more advantageous than the previous two-drug combination in alleviating amyloid beta (Aβ)-induced nerve cell toxicity. Cell viability assay was performed to screen these agents, and further validation tests, including determination of cellular oxidative stress, apoptosis, and activity of the AKT/MDM2/p53 pathway, were performed. Among the nine candidate compounds, only silibinin at 1 µM reduced Aβ25–35-induced toxicity in PC12 cells. The neuroprotective effects of 1 µM silibinin in combination with 5 µM curcumin and 0.5 µM vorinostat (CVS) was shown in PC12 cells, in which it decreased apoptosis and oxidative stress marker levels that were increased by 20 µM Aβ25–35. Western blotting results showed that CVS pretreatment significantly increased the phosphorylation of AKT, BAD, and MDM2, which resulted in decreased intracellular expression of p53. Further, immunofluorescence results showed reduced p53 levels in the nuclei of PC12 cells following CVS pretreatment, indicating a reduction in the p53-mediated transcriptional activity associated with Aβ25–35 exposure. In conclusion, our findings suggested that pretreatment with CVS protected PC12 cells from Aβ25–35-induced toxicity through modulation of the AKT/MDM2/p53 pathway. Thus, CVS may present a new therapeutic option for treating AD.
OsteoporosAtlas: a human osteoporosis-related gene database
Authors: Wang Xun , Diao Lihong , Sun Dezhi , Wang Dan , Zhu Jiarun , He Yangzhige , Liu Yuan , Xu Hao , Zhang Yi , Liu Jinying , Wang Yan , He Fuchu , Li Yang , Li Dong 
Published: April 2019

BackgroundOsteoporosis is a common, complex disease of bone with a strong heritable component, characterized by low bone mineral density, microarchitectural deterioration of bone tissue and an increased risk of fracture. Due to limited drug selection for osteoporosis and increasing morbidity, mortality of osteoporotic fractures, osteoporosis has become a major health burden in aging societies. Current researches for identifying specific loci or genes involved in osteoporosis contribute to a greater understanding of the pathogenesis of osteoporosis and the development of better diagnosis, prevention and treatment strategies. However, little is known about how most causal genes work and interact to influence osteoporosis. Therefore, it is greatly significant to collect and analyze the studies involved in osteoporosis-related genes. Unfortunately, the information about all these osteoporosis-related genes is scattered in a large amount of extensive literature. Currently, there is no specialized database for easily accessing relevant information about osteoporosis-related genes and miRNAs.MethodsWe extracted data from literature abstracts in PubMed by text-mining and manual curation. Moreover, a local MySQL database containing all the data was developed with PHP on a Windows server.ResultsOsteoporosAtlas (http://biokb.ncpsb.org/osteoporosis/), the first specialized database for easily accessing relevant information such as osteoporosis-related genes and miRNAs, was constructed and served for researchers. OsteoporosAtlas enables users to retrieve, browse and download osteoporosis-related genes and miRNAs. Gene ontology and pathway analyses were integrated into OsteoporosAtlas. It currently includes 617 human encoding genes, 131 human non-coding miRNAs, and 128 functional roles. We think that OsteoporosAtlas will be an important bioinformatics resource to facilitate a better understanding of the pathogenesis of osteoporosis and developing better diagnosis, prevention and treatment strategies.
MorphoCatcher: a multiple-alignment based web tool for target selection and designing taxon-specific primers in the loop-mediated isothermal amplification method
Authors: Shirshikov Fedor V. , Pekov Yuri A. , Miroshnikov Konstantin A. 
Published: April 2019

Background
Advantages of loop-mediated isothermal amplification in molecular diagnostics allow to consider the method as a promising technology of nucleic acid detection in agriculture and medicine. A bioinformatics tool that provides rapid screening and selection of target nucleotide sequences with subsequent taxon-specific primer design toward polymorphic orthologous genes, not only unique or conserved common regions of genome, would contribute to the development of more specific and sensitive diagnostic assays. However, considering features of the original software for primer selection, also known as the PrimerExplorer (Eiken Chemical Co. LTD, Tokyo, Japan), the taxon-specific primer design using multiple sequence alignments of orthologs or even viral genomes with conservative architecture is still complicated.

Findings
Here, MorphoCatcher is introduced as a fast and simple web plugin for PrimerExplorer with a clear interface. It enables an execution of multiple-alignment based search of taxon-specific mutations, visual screening and selection of target sequences, and easy-to-start specific primer design using the PrimerExplorer software. The combination of MorphoCatcher and PrimerExplorer allows to perform processing of the multiple alignments of orthologs for informative sliding-window plot analysis, which is used to identify the sequence regions with a high density of taxon-specific mutations and cover them by the primer ends for better specificity of amplification.

Conclusions
We hope that this new bioinformatics tool developed for target selection and taxon-specific primer design, called the MorphoCatcher, will gain more popularity of the loop-mediated isothermal amplification method for molecular diagnostics community. MorphoCatcher is a simple web plugin tool for the PrimerExplorer software which is freely available only for non-commercial and academic users at http://morphocatcher.ru.
Application of Information and Communication Technology (ICT) in Farm Management in Jorhat District of Assam
Authors: Lahan Raktim Ranjan , Deka Nivedita 
Published: April 2019

Information Communication Technology (ICT) provides an opportunity for farmers to increase their farm production.ICT is a diverse set of technological tools and resources used to communicate, disseminate, store and manage information. Different tools of ICT like television, radio, newspaper, mobile phone, etc were used by the farmers to get information. The demand for agricultural crops increasing day by day to feed the people. Proper information about weather, plant disease, soil, the post-harvesting technique can increase the productivity of the farmers. In the present study, all the sources were divided into four groups accordingly their characteristics. The four groups were face to face, other farmers, traditional media, modern ICT etc. Different factors were affecting in the use of modern ICT like age, education, farm size, traditional media, mobile phone. Some factors were affecting more in the use of ICT while some factors affecting less. Old age farmers relied more on traditional media than modern ICT. Farmers those who had large farm size were using more traditional media and modern ICT. Various problems were faced by farmers while using ICT. The present study tries to know the use of ICT and factors affecting in the use of ICT.
From the individual to the collective: The emergence of a psychological approach to collective memory
Authors: Stone Charles B. , Jay Alexander C.V. 
Published: April 2019

SummaryThroughout much of the 20th century, psychologists have largely examined mnemonic processes through an individualistic lens at the expense of social influences. However, this perspective began to change toward the end of the 20th century and beginning of the 21st century, when psychologists began to better appreciate the social nature of remembering. In the present paper, we focus on a relatively recent and important evolution of this line of research: the emergence of a psychological approach to collective memory. Using an epidemiological approach to collective memory, we attempt to distil the extant and relevant psychological research and focus on how (collective) memories transmit, converge, and remain stable over time while considering the bidirectional relationship between collective memory and a mnemonic community's identity. We conclude with a discussion of research areas that psychologists should examine moving forward, which will ultimately provide a more holistic understanding of how collective memories emerge, remain stable, and/or change over time.
A Novel Bifunctional Self‐Stabilized Strategy Enabling 4.6 V LiCoO2 with Excellent Long‐Term Cyclability and High‐Rate Capability
Authors: Wang Longlong , Ma Jun , Wang Chen , Yu Xinrun , Liu Ru , Jiang Feng , Sun Xingwei , Du Aobing , Zhou Xinhong , Cui Guanglei 
Published: April 2019

AbstractAlthough the theoretical specific capacity of LiCoO2 is as high as 274 mAh g−1, the superior electrochemical performances of LiCoO2 can be barely achieved due to the issues of severe structure destruction and LiCoO2/electrolyte interface side reactions when the upper cutoff voltage exceeds 4.5 V. Here, a bifunctional self‐stabilized strategy involving Al+Ti bulk codoping and gradient surface Mg doping is first proposed to synchronously enhance the high‐voltage (4.6 V) performances of LiCoO2. The comodified LiCoO2 (CMLCO) shows an initial discharge capacity of 224.9 mAh g−1 and 78% capacity retention after 200 cycles between 3.0 and 4.6 V. Excitingly, the CMLCO also exhibits a specific capacity of up to 142 mAh g−1 even at 10 C. Moreover, the long‐term cyclability of CMLCO/mesocarbon microbeads full cells is also enhanced significantly even at high temperature of 60 °C. The synergistic effects of this bifunctional self‐stabilized strategy on structural reversibility and interfacial stability are demonstrated by investigating the phase transitions and interface characteristics of cycled LiCoO2. This work will be a milestone breakthrough in the development of high‐voltage LiCoO2. It will also present an instructive contribution for resolving the big structural and interfacial challenges in other high‐energy‐density rechargeable batteries.
Solar Energy Storage by Molecular Norbornadiene–Quadricyclane Photoswitches: Polymer Film Devices
Authors: Petersen Anne Ugleholdt , Hofmann Anna I. , Fillols Méritxell , Mansø Mads , Jevric Martyn , Wang Zhihang , Sumby Christopher J. , Müller Christian , Moth‐Poulsen Kasper 
Published: April 2019

AbstractDevices that can capture and convert sunlight into stored chemical energy are attractive candidates for future energy technologies. A general challenge is to combine efficient solar energy capture with high energy densities and energy storage time into a processable composite for device application. Here, norbornadiene (NBD)–quadricyclane (QC) molecular photoswitches are embedded into polymer matrices, with possible applications in energy storing coatings. The NBD–QC photoswitches that are capable of absorbing sunlight with estimated solar energy storage efficiencies of up to 3.8% combined with attractive energy storage densities of up to 0.48 MJ kg−1. The combination of donor and acceptor units leads to an improved solar spectrum match with an onset of absorption of up to 529 nm and a lifetime (t1/2) of up to 10 months. The NBD–QC systems with properties matched to a daily energy storage cycle are further investigated in the solid state by embedding the molecules into a series of polymer matrices revealing that polystyrene is the preferred choice of matrix. These polymer devices, which can absorb sunlight and over a daily cycle release the energy as heat, are investigated for their cyclability, showing multicycle reusability with limited degradation that might allow them to be applied as window laminates.