bluuebunny/crossref_metadata_2025 huggingface dataset:
Spiky Structures around Reconnection Exhausts in the Solar Wind
Authors: Enžl Jakub , Šafránková Jana , Němeček Zdeněk , Přech Lubomír
Published: December 2017

The paper presents for the first time observations of unusual reconnection events in the solar wind. In all solar wind types, we identify magnetic reconnection exhausts accompanied by one or two side jets. This complex structure is created around a single current sheet and the jet(s) oriented in the same direction as the main exhaust is (are) spatially separated from it. A statistical analysis of reconnection exhausts in Wind observations (422 events) revealed that about 12% of exhausts is accompanied with one side jet and 3% of exhausts is bounded by two side jets, one on each side. Multispacecraft observations of events allow us to conclude that these structures are not consistent with a folding of the reconnection exhaust boundary. A source of these side jets is probably multiple or patchy reconnection at or close to the heliospheric current sheet. We suggest a scenario based on multiple reconnection that would lead to the presence of two side jets. A single jet is caused by a broken X-line consisting of two or more spatially separated parts.
Testing for Shock-heated X-Ray Gas around Compact Steep Spectrum Radio Galaxies
Authors: O’Dea C. P. , Worrall D. M. , Tremblay G. R. , Clarke T. E. , Rothberg B. , Baum S. A. , Christiansen K. P. , Mullarkey C. A. , Noel-Storr J. , Mittal R.
Published: December 2017

We present Chandra and XMM-Newton X-ray, Very Large Array (VLA) radio, and optical observations of three candidate compact steep spectrum (CSS) radio galaxies. CSS sources are of a galactic scale and are presumably driving a shock through the interstellar medium (ISM) of their host galaxy. B3 1445+410 is a low-excitation emission line CSS radio galaxy with possibly a hybrid Fanaroff–Riley FRI/II (or fat double) radio morphology. The Chandra observations reveal a point-like source that is well fit with a power law consistent with the emission from a Doppler boosted core. 3C 268.3 is a CSS broad-line radio galaxy (BLRG) whose Chandra data are consistent spatially with a point source centered on the nucleus and spectrally with a double power-law model. PKS B1017–325 is a low-excitation emission line radio galaxy with a bent double radio morphology. While from our new spectroscopic redshift, PKS B1017−325 falls outside the formal definition of a CSS, the XMM-Newton observations are consistent with ISM emission with either a contribution from hot shocked gas or non-thermal jet emission. We compile selected radio and X-ray properties of the nine bona fide CSS radio galaxies with X-ray detections so far. We find that two out of the nine show X-ray spectroscopic evidence for hot shocked gas. We note that the counts in the sources are low and that the properties of the two sources with evidence for hot shocked gas are typical of the other CSS radio galaxies. We suggest that hot shocked gas may be typical of CSS radio galaxies due to their propagation through their host galaxies.
Interpreting Brightness Asymmetries in Transition Disks: Vortex at Dead Zone or Planet-carved Gap Edges?
Authors: Regály Zs. , Juhász A. , Nehéz D.
Published: December 2017

Recent submillimeter observations show nonaxisymmetric brightness distributions with a horseshoe-like morphology for more than a dozen transition disks. The most-accepted explanation for the observed asymmetries is the accumulation of dust in large-scale vortices. Protoplanetary disks’ vortices can form by the excitation of Rossby wave instability in the vicinity of a steep pressure gradient, which can develop at the edges of a giant planet–carved gap or at the edges of an accretionally inactive zone. We studied the formation and evolution of vortices formed in these two distinct scenarios by means of two-dimensional locally isothermal hydrodynamic simulations. We found that the vortex formed at the edge of a planetary gap is short-lived, unless the disk is nearly inviscid. In contrast, the vortex formed at the outer edge of a dead zone is long-lived. The vortex morphology can be significantly different in the two scenarios: the vortex radial and azimuthal extensions are ∼1.5 and ∼3.5 times larger for the dead-zone edge compared to gap models. In some particular cases, the vortex aspect ratios can be similar in the two scenarios; however, the vortex azimuthal extensions can be used to distinguish the vortex formation mechanisms. We calculated predictions for vortex observability in the submillimeter continuum with ALMA. We found that the azimuthal and radial extent of the brightness asymmetry correlates with the vortex formation process within the limitations of α-viscosity prescription.
Characterizing Dust Attenuation in Local Star-forming Galaxies: Inclination Effects and the 2175 Å Feature
Authors: Battisti A. J. , Calzetti D. , Chary R.-R.
Published: December 2017

We characterize the influence that inclination has on the shape and normalization in average dust attenuation curves derived from a sample of ∼10,000 local star-forming galaxies. To do this, we utilize aperture-matched multiwavelength data from the Galaxy Evolution Explorer, the Sloan Digital Sky Survey, the United Kingdom Infrared Telescope, and the Two Micron All-sky Survey. We separate our sample into groups according to axial ratio (b/a) and obtain an estimate of their average total-to-selective attenuation

. The attenuation curves are found to be shallower at UV wavelengths with increasing inclination, whereas the shape at longer wavelengths remains unchanged. The highest inclination subpopulation (

) exhibits an NUV excess in its average selective attenuation, which, if interpreted as a 2175 Å feature, is best fit with a bump strength of 17%–26% of the MW value. No excess is apparent in the average attenuation curve of lower inclination galaxies. The differential reddening between the stellar continuum and ionized gas is found to decrease with increasing inclination. We find that higher inclination galaxies have slightly higher values of R

V
, although this is poorly constrained given the uncertainties. We outline possible explanations for these trends within a two component dust model (dense cloud+diffuse dust) and find that they can be naturally explained if carriers of the 2175 Å feature are preferentially destroyed in star-forming regions (UV-bright regions).
Statistical Studies of Solar White-light Flares and Comparisons with Superflares on Solar-type Stars
Authors: Namekata Kosuke , Sakaue Takahito , Watanabe Kyoko , Asai Ayumi , Maehara Hiroyuki , Notsu Yuta , Notsu Shota , Honda Satoshi , Ishii Takako T. , Ikuta Kai , Nogami Daisaku , Shibata Kazunari
Published: December 2017

Recently, many superflares on solar-type stars have been discovered as white-light flares (WLFs). The statistical study found a correlation between their energies (E) and durations (τ):

, similar to those of solar hard/soft X-ray flares,

. This indicates a universal mechanism of energy release on solar and stellar flares, i.e., magnetic reconnection. We here carried out statistical research on 50 solar WLFs observed with Solar Dynamics Observatory/HMI and examined the correlation between the energies and durations. As a result, the E–τ relation on solar WLFs (

) is quite similar to that on stellar superflares (

). However, the durations of stellar superflares are one order of magnitude shorter than those expected from solar WLFs. We present the following two interpretations for the discrepancy: (1) in solar flares, the cooling timescale of WLFs may be longer than the reconnection one, and the decay time of solar WLFs can be elongated by the cooling effect; (2) the distribution can be understood by applying a scaling law (

) derived from the magnetic reconnection theory. In the latter case, the observed superflares are expected to have 2–4 times stronger magnetic field strength than solar flares.
Superorbital Modulation at GeV Energies in the γ-Ray Binary LS I + 61°303
Authors: Xing Yi , Wang Zhongxiang , Takata Jumpei
Published: December 2017

We report the results from our analysis of eight years of the data for the γ-ray binary LS I +61°303, obtained with the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. We find a significant dip around the binary’s periastron in the superorbital light curves, and by fitting the light curves with a sinusoidal function, clear phase shifts are obtained. The superorbital modulation seen in the binary has been long known and different scenarios have been proposed. Based on our results, we suggest that the circumstellar disk around the Be companion of this binary may have a non-axisymmetric structure, which rotates at the superorbital period of 1667 days. As a result, the density of the ambient material around the compact star of the binary changes along the binary orbit over the superorbital period, causing the phase shifts in the modulation, and around periastron, the compact star probably enters the Be disk or switches the mode of its emission due to the intereaction with the disk, causing the appearance of the dip. We discuss the implications of this possible scenario to the observed superorbital properties at multiple frequencies.
Modeling UV Radiation Feedback from Massive Stars. I. Implementation of Adaptive Ray-tracing Method and Tests
Authors: Kim Jeong-Gyu , Kim Woong-Tae , Ostriker Eve C. , Skinner M. Aaron
Published: December 2017

We present an implementation of an adaptive ray-tracing (ART) module in the Athena hydrodynamics code that accurately and efficiently handles the radiative transfer involving multiple point sources on a three-dimensional Cartesian grid. We adopt a recently proposed parallel algorithm that uses nonblocking, asynchronous MPI communications to accelerate transport of rays across the computational domain. We validate our implementation through several standard test problems, including the propagation of radiation in vacuum and the expansions of various types of H ii regions. Additionally, scaling tests show that the cost of a full ray trace per source remains comparable to that of the hydrodynamics update on up to

∼

10

3

processors. To demonstrate application of our ART implementation, we perform a simulation of star cluster formation in a marginally bound, turbulent cloud, finding that its star formation efficiency is 12% when both radiation pressure forces and photoionization by UV radiation are treated. We directly compare the radiation forces computed from the ART scheme with those from the M
1 closure relation. Although the ART and M
1 schemes yield similar results on large scales, the latter is unable to resolve the radiation field accurately near individual point sources.
Planet–Planet Occultations in TRAPPIST-1 and Other Exoplanet Systems
Authors: Luger Rodrigo , Lustig-Yaeger Jacob , Agol Eric
Published: December 2017

We explore the occurrence and detectability of planet–planet occultations (PPOs) in exoplanet systems. These are events during which a planet occults the disk of another planet in the same system, imparting a small photometric signal as its thermal or reflected light is blocked. We focus on the planets in TRAPPIST-1, whose orbital planes we show are aligned to

at 90% confidence. We present a photodynamical model for predicting and computing PPOs in TRAPPIST-1 and other systems for various assumptions of the planets’ atmospheric states. When marginalizing over the uncertainties on all orbital parameters, we find that the rate of PPOs in TRAPPIST-1 is about 1.4 per day. We investigate the prospects for detection of these events with the James Webb Space Telescope, finding that ∼10–20 occultations per year of b and c should be above the noise level at 12–15 μm. Joint modeling of several of these PPOs could lead to a robust detection. Alternatively, observations with the proposed Origins Space Telescope should be able to detect individual PPOs at high signal-to-noise ratios. We show how PPOs can be used to break transit timing variation degeneracies, imposing strong constraints on the eccentricities and masses of the planets, as well as to constrain the longitudes of nodes and thus the complete three-dimensional structure of the system. We further show how modeling of these events can be used to reveal a planet’s day/night temperature contrast and construct crude surface maps. We make our photodynamical code available on github (https://github.com/rodluger/planetplanet).
Magnetar-powered Superluminous Supernovae Must First Be Exploded by Jets
Authors: Soker Noam , Gilkis Avishai
Published: December 2017

We analyze recent magnetar light-curve modeling of 38 hydrogen-poor superluminous supernovae (SLSNe) and find that the energies of the explosions themselves, which take place before the magnetar energy is released, are more than what the neutrino-driven explosion mechanism can supply for about half of the systems. These SLSNe must have been exploded by a different process than the delayed neutrino mechanism, most likely the jet feedback mechanism. The conclusion for magnetar modeling of SLSNe is that jets launched at magnetar birth cannot be ignored, not at the explosion itself and not later when mass fall-back might occur. More generally, the present analysis strengthens the call for a paradigm shift from neutrino-driven to jet-driven explosion models of all core collapse supernovae.
Statistical Hierarchy of Varying Speed of Light Cosmologies
Authors: Salzano Vincenzo , Da̧browski Mariusz P.
Published: December 2017

Many varying speed of light (VSL) theories have been developed recently. Here we address the issue of their observational verification in a fully comprehensive way. By using the most updated cosmological probes, we test three different candidates for a VSL theory (Barrow & Magueijo, Avelino & Martins, and Moffat). We consider many different Ansätze for both the functional form of c(z) and the dark energy dynamics. We compare these results using a reliable statistical tool such as the Bayesian evidence. We find that the present cosmological data are perfectly compatible with any of these VSL scenarios, but for the Moffat model there is a higher Bayesian evidence ratio in favor of VSL rather than the c = constant ΛCDM scenario. Moreover, in such a scenario, the VSL signal can help to strengthen constraints on the spatial curvature (with indication toward an open universe), to clarify some properties of dark energy (exclusion of a cosmological constant at

level), and is also falsifiable in the near future owing to peculiar issues that differentiate this model from the standard one. Finally, we apply an information prior and entropy prior in order to put physical constraints on the models, though still in favor Moffat’s proposal.
De la religion tranquille, au fanatisme sacrificiel
Authors: Pommier Gérard
Published: December 2017

La religion a été le premier mode d’organisation des sociétés humaines. Elle légitimait le pouvoir politique. L’histoire des religions a évolué en allant de l’animisme au polythéisme, puis au monothéisme, pour aboutir à une forme d’athéisme pratique, relayé par une certaine idéalisation de la science. Cela veut-il dire que le sens du sacré va disparaître ? Non, car le fait religieux s’appuie sur des croyances de l’enfance, qui subsisteront sous d’autres formes, notamment grâce à la psychanalyse. Elle révèle à chacun quelle a été sa religion privée, et un sens du sacré coupé de ses attaches communautaires, si souvent aliénantes.
¿Es el recurso humano un elemento generador de ventajas competitivas? Aplicación a una entidad de la banca chilena
Authors: Barra Salazar Ana María , San Martín Coronado Roxana
Published: December 2017

Ce document vise à analyser la relation entre les ressources et les capacités d’une organisation et ses résultats, pour expliquer l’existence d’avantages concurrentiels qui devraient la conduire à une différenciation par rapport aux autres entreprises du même secteur. Les variables étudiées sont la formation, l’ancienneté, la satisfaction et les résultats de l’entreprise. En outre la connaissance pratique, de la satisfaction, la formation ou le perfectionnement continu des travailleurs montre leur contribution à créer un avantage concurrentiel au profit de l’organisation, conduisant à de meilleurs résultats commerciaux.
Diseño del modelo de vinculación en una universidad pública en México: desarrollo sustentable y responsabilidad social
Authors: Morales Espinosa Elda Aurora , Vázquez García Angel Wilhelm , Álvarez Morales Aketzalli
Published: December 2017

Pour la conception d’un modèle le niveau « systémique » devient particulièrement important comme guide de lecture et de mise-en-œuvre des stratégies à encadrer et coordonner. La mondialisation a créé une constante d’induction des identités qui va des pays centrales industrialisés aux pays émergents vers la périphérie. Les effets négatifs de la mondialisation sur la population générale poussent les différents acteurs, les gouvernements, les entreprises, la société civile, et les établissements d’enseignement, à adopter la responsabilité sociale en réponse aux postulats du nouvel ordre économique et social qui se dégage au XXI siècle aux écarts d’inégalité. L’objectif de cette recherche est la délocalisation du débat sur la responsabilité sociale, normalement relié aux affaires, et de l’aborder à partir d’une perspective de l’université publique. Ainsi, on connaitra la mesure dans laquelle les pratiques discursives et la responsabilité sociale, répondent à un modèle d’inclusion sociale. Pour cela nous faisons une révision de la littérature internationale sur les principaux accords dans le domaine du développement durable et de la responsabilité sociale. L’objectif est de proposer un modèle de liens éducatifs pour le développement social, en mettant l’accent sur la durabilité et la responsabilité sociale.
Neoliberalism French Style : marché et politique dans la gestion de l'environnement à Nantes
Authors: Béal Vincent
Published: December 2017

Résumé L'environnement constitue aujourd'hui un enjeu structurant pour l'action publique urbaine. Souvent présentées comme des freins au renforcement des logiques entrepreneuriales en ville, les politiques urbaines d'environnement ne sont pourtant pas extérieures au contexte néolibéral qui caractérise la gestion urbaine. En prenant appui sur une analyse des politiques environnementales de la ville de Nantes, l'article s'intéresse à l'intégration inachevée des mécanismes marchands et des enjeux de compétitivité dans la production des éco-quartiers et la lutte contre le changement climatique. Il montre ainsi que les villes françaises n'ont pas été épargnées par les processus de néolibéralisation. Ces processus restent toutefois hybrides et sélectifs. Ils se caractérisent par un renforcement des logiques marchandes et de compétition qui n'est pas exclusif du maintien de régulations politiques, lesquelles sont destinées, notamment, à entretenir des soutiens électoraux et à construire des coalitions de gouvernement.
Factors influencing purchase intention towards consumer-to-consumer e-commerce
Authors: Dachyar Muhammad , Banjarnahor Liska
Published: December 2017

Purpose: This study explores factors that influence consumer’s purchase intention at three consumer-to-consumer (C2C) e-commerce companies in Indonesia.Design/methodology/approach: 5 Expert opinions are used to determine the indicators of each factor and the Structural Equation Modelling (SEM) method is used to analyze the empirical data of  400 respondents for each company.Findings: It is found different significant factors that influence customer’s purchase intention in each company. Trust and risk are found to be significantly effect purchase intention in Company A. Meanwhile, the other two companies, perceived usefulness proved to be significant in Company B and benefit significantly effect consumer purchase intention in Company C.Originality/value: This study represents purchase intention in the consumer-to-consumer e-commerce by investigating three case study using technology acceptance model as a guiding theory.
Le phénomène Proto-Élamite et la construction archéologique de la révolution proto-urbaine en Iran du Sud-Ouest
Authors: Naccaro Hugo
Published: December 2017

Le tournant des IVe et IIIe millénaires avant J.-C. en Iran du sud-ouest est marqué par une révolution majeure : celle de l’apparition de l’État et de l’écriture. Elle est plus précisément la période d’aboutissement de la révolution proto-urbaine, résultat d’un long processus, commencé dès le Ve millénaire.Le terme « proto-élamite » a été, dans un premier temps, une dénomination issue de la philologie. Il permettait de définir une écriture différente de la tradition sud mésopotamienne qui apparaît à la toute fin du IVe millénaire en Iran du sud-ouest. Cette dénomination a par la suite acquis une connotation archéologique (période, culture et « civilisation »). À partir du modèle d’expansion proto-urbaine sud mésopotamien dit d’ « Uruk » (IVe millénaire), le terme proto-élamite a également permis de désigner un phénomène de même nature en Iran entre 3300/3100 et 2800/2600 av. J.-C.. Ces deux phénomènes (Uruk et proto-élamite) sont nettement différenciés : chronologie, culture matérielle, écriture, originalité artistique. Cependant ils sont indubitablement liés. De nouvelles découvertes et recherches poussent aujourd’hui différentes écoles à remettre en cause la construction archéologique du « phénomène Proto-Élamite ». En effet, l’emploi de cette terminologie a été utilisé afin de désigner une théorique généralisation de la « révolution urbaine » sur une aire géographique très importante et sur un temps relativement court. Cette construction permet d’illustrer les bouleversements radicaux dans l’évolution des sociétés iraniennes à cette période, visibles au travers des restes archéologiques. Cependant elle pose de nombreux problèmes méthodologiques.L’objet de cet article est de tester l’existence du concept du « phénomène proto-élamite » comme « phénomène proto-urbain » en Iran du sud-ouest. Nous aborderons ainsi son historiographie complexe, son analogie fragile avec le phénomène urukéen, en nous appuyant sur nos recherches en stratigraphie urbaine et sur le matériel.
New records for Lygaeus creticus Lucas, 1854 in Italy and Corsica (Hemiptera: Heteroptera: Lygaeidae).
Authors: Cianferoni Fabio , Ceccolini Filippo , Dioli Paride
Published: December 2017

First occurrence records for Lygaeus creticus Lucas, 1854 in Trentino- Alto Adige, Apulia, Pantelleria Island, and Corsica are given. First records with precise locality for Tuscany are also provided.
On the kriging of water table elevations using collateral information from a digital elevation model
Authors: Desbarats A J , Logan C E , Hinton M
J , Sharpe D R
Published: December 2017

In unconfined aquifers flowing under topographic gradients, the water table is a subdued replica of the ground surface above. This principle is the basis for using detailed collateral or secondary information from digital elevation models to supplement sparse
observations from water wells in the mapping of phreatic surfaces. Data from DEM-derived secondary variables are incorporated into the estimation of water table elevations using the geostatistical method known as kriging with an external drift (KED). Two different KED models are proposed based on
the choice of secondary variable. In the first, water table elevation is expressed as the sum of a deterministic trend given by topographic elevation and a residual random component representing depth to water table. In the second, depth to water table is expressed as a linear function of a
deterministic trend, given by the TOPMODEL topographic index, and a residual random error. The relationship between water table depth and topographic index is derived from simplified groundwater dynamics and forms the basis of TOPMODEL-type rainfall-runoff models. The two KED models are applied to
the mapping of water table elevations in the Oak Ridges Moraine (ORM), an unconfined aquifer near Toronto, Canada. Results show that KED with topographic elevation as external drift is the more robust of the two models. Despite its strong theoretical basis, the second model yields kriged water table
elevations that are not always physically plausible. In part, this is because field observations of water table depth do not verify the predicated relationship with topographic index in large parts of the study area. However, this relationship may be valid in other cases and at other spatial scales.
In such cases, the second model would provide a very powerful approach for mapping water table elevations and for calibrating distributed parameters of the TOPMODEL equations on water well observations.
Om die Rubicon oor te steek: Oopmaak van die hekke in die Nederduitsch Hervormde Kerk van Afrika/Crossing the Rubicon: Opening of gates in the Netherdutch Reformed Church in Africa
Authors: Van Eck Ernest
Published: December 2017

On the occasion of the 500 year commemoration of the Reformation and the centenary celebration of the Faculty of Theology HTS Centenary Volume Two is dedicated to the Netherdutch Reformed Church in Africa (NRCA), the oldest partner of the theological faculty at the University of Pretoria – with grateful recognition to what the NRCA contributed to the practice of critical theology in South Africa over the past 100 years and its support of HTS Theological Studies as title owner for 73 years. HTS Centenary Volume Two takes the form of a compendium of the most important documents that preceded and followed the ‘crossing of the Rubicon’ in the NRCA, as well as the publication of three special collections, namely ‘100 jaar Hervormde Teologie’ (edited by Wim Dreyer), ‘Hervormde teoloë in gesprek’ (edited by Christo van der Merwe), and ‘Kerkhervorming 1517–2017’ (edited by Natie van Wyk).By geleentheid van die 500 jaar herdenking van die Reformasie en die eeufees van die Fakulteit Teologie van die Universiteit van Pretoria, word HTS se Eeufeesbundel Volume Twee opgedra aan die Nederduitsch Hervormde Kerk van Afrika (NHKA), die oudste kerklike vennoot van die teologiese fakulteit aan die Universiteit van Pretoria – uit dankbare erkenning vir wat die NHKA tot die beoefening van kritiese teologie in die afgelope 100 jaar in Suid Afrika bygedra het en vir die ondersteuning van HTS Teologiese Studies as titeleienaar vir 73 jaar. HTS se Eeufeesbundel Volume Twee neem die vorm aan van ’n kompendium van die belangrikste dokumente wat die ‘oorsteek van die Rubicon’ in die NHKA voorafgegaan en opgevolg het, sowel as die publikasie van drie spesiale kolleksies, te wete ‘100 jaar Hervormde Teologie’ (onder redakteurskap van Wim Dreyer), ‘Hervormde teoloë in gesprek’ (onder redakteurskap van Christo van der Merwe), en ‘Kerkhervorming 1517–2017’ (onder redakteurskap van Natie van Wyk).
Die toets van ekstrakte uit Sutherlandia frutescens (Fabaceae) op Mycobacterium smegmatis in die behandeling van tuberkulose
Authors: Mabusa Itumeleng H. , Howard Rachmond , Masoko Peter
Published: December 2017

Sutherlandia frutescens (L) R. Br. bevat verskeie essensiële bioaktiewe verbindings met farmakologiese aktiwiteit waarvoor daar kliniese bewyse bestaan. Sutherlandia word vir mense met tuberkulose voorgeskryf, maar niemand weet nog watter verbindings in hierdie plant Mycobacterium tuberculosis en die werking daarvan teenwerk nie. Hierdie studie het ten doel om te bepaal of S. frutescens antimikobakteriese verbindings bevat. Bogrondse dele van S. frutescens is gedroog, gemaal en met etanol:metanol [1:1] (vol./vol.) en water onttrek. Die chemiese profiel is bepaal deur hoëverrigting vloeistofchromatografie-massaspektrometrie en dunlaag-chromatografie te gebruik. Die dunlaagchromatografie is in butanol:asynsuur:water (BAW) [21:6:3], chloroform:metanol:water:mieresuur (CMWM1) [60:15:2:1] en CMWM2 [21:9:1:0.3] ontwikkel. Die kwalitatiewe anti-oksidant-aktiwiteit is bepaal deur 2.2 difeniel-2-pikrielhidrasiel (DFPH) te gebruik. Die antimikobakteriese aktiwiteit van die plantekstrakte is bepaal deur mikro-verdunning en bio-outografiese metodes teen Mycobacterium smeagmatis te gebruik. Ons het lae antimikobakteriese aktiwiteit teen M. smegmatis in die bio-outogramme waargeneem. Die profiele van die hoëverrigting vloeistofchromatograpfie-massaspektrometrie het meer verbindings in die etanolekstrakte as in die waterekstrakte aangedui. Die gemiddelde waardes vir minimum inhibeerderkonsentrasie vir al die ekstrakte was 0.61 mg/mL. Die DCM:MeOH (1:1) ekstrak het die laagste minimum inhibeerderkonsentrasie-waarde, naamlik 0.28 mg/mL gehad. Die resultate het getoon dat die plant verder vir moontlike antimikobakteriese agente ondersoek kan word. Lae aktiwiteit is waargeneem, waarskynlik as gevolg van stadig vermeerderende bacilli en nie-vermeerderende organismes. Die studie bied voorlopige wetenskaplike ondersteuning vir die tradisionele medisinale gebruik van hierdie plant. Navorsing korrelasie: Hierdie artikel is die vertaalde weergawe en is beskikbaar gestel om ‘n breër lesersgroep te bereik. Die oorspronklike Engelse artikel is beskikbaar hier: https://doi.org/10.4102/satnt.v36i1.1486
Generalized open sets in grill N-topology
Authors: Thivagar M. Lellis , Reilly Ivan L , Dasan M. Arockia , Ramesh V.
Published: December 2017

The aim of this paper is to give a systematic development of grill N-topological spaces and discuss a few properties of local function. We build a topology for the corresponding grill by using the local function. Furthermore, we investigate the properties of weak forms of open sets in the grill N-topological spaces and discuss the relationships between them.
Quasi-uniform convergence topologies on function spaces- Revisited
Authors: Alqurash Wafa Khalaf , Khan Liaqat Ali
Published: December 2017

Let X and Y be topological space and F(X,Y) the set of all functions from X into Y. We study various quasi-uniform convergence topologies U_{A} (A⊆P(X)) on F(X,Y) and their comparison in the setting of Y a quasi-uniform space. Further, we study U_{A}-closedness and right K-completeness properties of certain subspaces of generalized continuous functions in F(X,Y) in the case of Y a locally symmetric quasi-uniform space or a locally uniform space.
A study of function space topologies for multifunctions
Authors: Gupta Ankit , Sarma Ratna Dev
Published: December 2017

Function space topologies are investigated for the class of continuous multifunctions. Using the notion of continuous convergence, splittingness and admissibility are discussed for the topologies on continuous multifunctions. The theory of net of sets is further developed for this purpose. The (τ,μ)-topology on the class of continuous multifunctions is found to be upper admissible, while the compact-open topology is upper splitting. The point-open topology is the coarsest topology which is coordinately admissible, it is also the finest topology which is coordinately splitting. 
Version 2 of the IASI NH3 neural network retrieval algorithm: near-real-time and reanalysed datasets
Authors: Van Damme Martin , Whitburn Simon , Clarisse Lieven , Clerbaux Cathy , Hurtmans Daniel , Coheur Pierre-François
Published: December 2017

Abstract. Recently, Whitburn et al.(2016) presented a neural-network-based algorithm for retrieving atmospheric ammonia (NH3) columns from Infrared Atmospheric Sounding Interferometer (IASI) satellite observations. In the past year, several improvements have been introduced, and the resulting new baseline version, Artificial Neural Network for IASI (ANNI)-NH3-v2.1, is documented here. One of the main changes to the algorithm is that separate neural networks were trained for land and sea observations, resulting in a better training performance for both groups. By reducing and transforming the input parameter space, performance is now also better for observations associated with favourable sounding conditions (i.e. enhanced thermal contrasts). Other changes relate to the introduction of a bias correction over land and sea and the treatment of the satellite zenith angle. In addition to these algorithmic changes, new recommendations for post-filtering the data and for averaging data in time or space are formulated. We also introduce a second dataset (ANNI-NH3-v2.1R-I) which relies on ERA-Interim ECMWF meteorological input data, along with surface temperature retrieved from a dedicated network, rather than the operationally provided Eumetsat IASI Level 2 (L2) data used for the standard near-real-time version. The need for such a dataset emerged after a series of sharp discontinuities were identified in the NH3 time series, which could be traced back to incremental changes in the IASI L2 algorithms for temperature and clouds. The reanalysed dataset is coherent in time and can therefore be used to study trends. Furthermore, both datasets agree reasonably well in the mean on recent data, after the date when the IASI meteorological L2 version 6 became operational (30 September 2014).
A global assessment of gross and net land change dynamics for current conditions and future scenarios
Authors: Fuchs Richard , Prestele Reinhard , Verburg Peter H.
Published: December 2017

Abstract. The consideration of gross land changes, meaning all area gains and losses within a pixel or administrative unit (e.g. country), plays an essential role in the estimation of total land changes. Gross land changes affect the magnitude of total land changes, which feeds back to the attribution of biogeochemical and biophysical processes related to climate change in Earth System Models. Global empirical studies on gross land changes are currently lacking. Whilst the relevance of gross changes for global change has been indicated in the literature, it is not accounted for in future land change scenarios. In this study, we extract gross and net land change dynamics from large-scale and high-resolution (30–100 m) remote sensing products to create a new global gross and net change dataset. Subsequently, we developed an approach to integrate our empirically derived gross and net changes with the results of future simulation models, by accounting for the gross and net change addressed by the land use model and the gross and net change that is below the resolution of modelling. Based on our empirical data, we found that gross land change within 0.5-degree grid cells were substantially larger than net changes in all parts of the world. As 0.5-degree grid cells are a standard resolution of Earth System Models, this leads to an underestimation of the amount of change. This finding contradicts earlier studies, which assumed gross land changes to appear in shifting cultivation areas only. Applied in a future scenario, the consideration of gross land changes led to approximately 50 % more land changes globally compared to a net land change representation. Gross land changes were most important in heterogeneous land systems with multiple land uses (e.g. shifting cultivation, smallholder farming, and agro-forestry systems). Moreover, the importance of gross changes decreased over time due to further polarization and intensification of land use. Our results serve as empirical database for land change dynamics that can be applied in Earth System Models and Integrated Assessment Models.
Análisis de las herramientas de producción radiofónica en las radios universitarias españolas
Authors: Bernad Mª Sagrario , Martín-Pena Daniel , Guillem Aldave Carlos
Published: December 2017

Una de las partes fundamentales para analizar cualquier estación radiofónica es conocer su equipamiento tecnológico, y si hablamos de emisoras universitarias esto adquiere aún mayor valor, por su potencial formativo de futuros profesionales de la comunicación y por su capacidad de experimentación e innovación innata a estas instituciones. El objetivo de este estudio es conocer las herramientas de producción técnica utilizadas por las emisoras universitarias españolas. Con este propósito hemos planteado una investigación de tipo cuantitativo para señalar los instrumentos más usuales en las emisoras universitarias y compararlos con los que se utilizan en un contexto real laboral. La conclusión principal es que las estaciones universitarias están dotadas de medios técnicos profesionales que podemos encontrar en una emisora de radio convencional, y que permiten al alumnado la manipulación del sonido y el descubrimiento de las posibilidades del lenguaje radiofónico. De esta manera, los productos radiofónicos elaborados por los estudiantes implicados en las emisoras contribuyen a reforzar su trayectoria educativa y formativa.
Aplicación, desarrollo y reforma de la Ley 5/2011 de Economía Social. ¿Un derecho debilitado?
Authors: Pérez de Uralde José María
Published: December 2017

La entrada en vigor de la Ley 5/2011, de Economía Social, debería haber contribuido a facilitar cierta elaboración científico-jurídica entorno a un posible Derecho de la Economía Social. Sin embargo, la parquedad de su texto, su falta de aplicación, la ausencia absoluta de desarrollo reglamentario y una reforma errónea, impiden tal pretensión. La inconsistente construcción técnica de esta Ley, su inaplicación radical, la falta de desarrollo reglamentario mínimo y una muy discutible reforma la configuran en términos de ineficiencia, aproximándola a un tipo de producción jurídica carente de efectos prácticos. La confusión de rangos normativos, el proceloso y confuso proceso deslegalizador al que es sometida, la indeterminación material y de fuentes, la inseguridad jurídica que todo ello propicia y, sobre todo, su flagrante y nocivo incumplimiento, la sitúan al borde mismo del llamado “Derecho blando” y/o del “Derecho imperfecto”, donde desaparecen las características más determinantes que otorga la llamada “fuerza de Ley”. La Economía Social merece otro trato legal que permita consolidar puntos de partida que alienten la construcción de un sistemático Derecho de la Economía Social, basado en la homologación de conceptos referenciales y permita culminar una construcción holística realmente necesaria.
The Price Discovery Mechanism between Sovereign Bond and Sovereign CDS Market: Studies in Selected Countries
Authors: Nguyen Ngan Bich
Published: December 2017

This paper employs the multivariate VAR model to examine the mechanic work of price discovery process between sovereign CDS market and the associated sovereign bond market in contexts of five European and Asian countries, including Vietnam, Korea, Portugal, Italy and France from the beginning of 2008 to the end of April, 2017. The study accentuates on three aspects: the short-term interaction nexus between the sovereign CDS and the associated-sovereign bond market, the long-term co-movement between them and the discovery of which market plays the leading role in the pricing process. The results evidence the short-run and long-run relationship for the two markets. Particularly, the empirical test results support for the predominant role of the sovereign CDS market in the price discovery process in the bulk of sample entities. This might suggests for the governments to use CDS prices as the future indicator for predicting the volatility of debt markets.
The Truth is in the Data – Differences in the Same Measure Based on Different
Sources among HVHC Members Using ICU Length of Stay as an Example
Authors: Von Recklinghausen Friedrich Maximilian , Taenzer Andreas , Gorman Chrissie , Knowlton Jay , Kinslow Allison , Russell Ron
Published: December 2017

Introduction: Intensive Care Unit (ICU) length of stay is a strong indicator of
severity of illness and cost in the care of sepsis patients. In this case study, we
examine the difference between an electronic health record (EHR) based submissions with
Centers for Medicare and Medicaid Services (CMS) payment data.Methods: Member submitted
EHR data contained 26,733 unique patient’s records. The CMS data contained demographics,
diagnosis, and revenue codes. After linking EHR data to CMS data, we found a discrepancy
in ICU days from CMS claims vs. EHR data. Our hypothesis was that removing intermediate
ICU LOS would result in a closer match from CMS claims with EHR data. We suspected the
use of Intermediate ICU stays in our CMS ICU definition contaminated our ICU LOS data.
This resulted in a review of the sepsis specification, further investigation of the
data, and follow up conversations with the Member organizations.Results: Agreement
between EHR and CMS data improved from 73 percent to 86 percent once the Intermediate
ICU time had been removed.Discussion and Conclusions: The inclusion of Intermediate ICU
in the analysis of severely ill sepsis patients from CMS data diluted the importance of
using an ICU LOS for estimating the severity of illness and the cost to the healthcare
system. We must ensure that clinical definitions are consistent between data sources
that were built for different purposes. Additionally, we learned that engaging with
clinicians, analysts, and clinical coders early in the process is required to fully
understand the complexities from different sources.
Appointment reminders by text message in a safety net health care system: a
pragmatic investigation
Authors: Fischer Henry H. , Moore Susan L. , Johnson Tracy L. , Everhart Rachel M. , Batal Holly , Davidson Arthur J.
Published: December 2017

Introduction: Short Message Service (SMS) appointment reminders may provide a
wide-reaching, low cost approach to reducing operational inefficiencies and improving
access to care. Previous studies indicate this modality may improve attendance rates,
yet there is a need for large-scale, pragmatic studies that include unintended
consequences and operational costs.Methods: This pragmatic investigation was a
before-after analysis that compared visit attendance outcomes among patients who opted
into SMS appointment reminders with outcomes among those who declined over an 18-month
evaluation period from March 25, 2013, to September 30, 2014. Eligibility in our
integrated safety net health care system included age greater than 17, English or
Spanish as a primary language, and a cell phone number in our scheduling system.Results:
47,390 patients were invited by SMS to participate, of which 20,724 (43.7 percent)
responded with 18,138 opting in (81.5 percent of respondents). Participants received SMS
reminders for 77,783 scheduled visits; comparison group patients (N=72,757) were
scheduled for 573,079 visits during the evaluation period. Intervention and comparison
groups had, respectively, attendance rates of 72.8 percent versus 66.1 percent
(p<0.001), cancellation rates of 13.2 percent versus 18.6 percent (p<0.001), and
no show rates of 14.0 percent versus 15.3 percent. Patient satisfaction with text
messaging ranged from 77 percent to 96 percent. Implementation challenges included a low
rate of inaccurate reminders due to non-standard use of the scheduling system across
clinical departments.Discussion: SMS appointment reminders improve patient satisfaction
and provide a low operating cost approach to reducing operational inefficiencies through
improved attendance rates in an integrated safety net health care system.
Traditional Risk Indices as Predictors of Future Utilization and Charges in the
Context of Population Health for an Uninsured Cohort
Authors: Lubanski Ethan T. , Rozario Nigel , Moore Charity G. , Mulder Holly Petruso , Dulin Michael , Ludden Tom , Rossman Whitney Ellefson , Ashby Avery , McWilliams Andrew
Published: December 2017

Introduction: The uninsured population presents unique challenges to the
application of an integrated approach to population health. Our objective is to compare
and test population risk indices for identifying a cohort of uninsured patients at
high-risk for avoidable healthcare utilization and costs.Methods: Patients who had a
least one visit at a safety-net clinic, had a primary address in Mecklenburg County,
were aged 18-74, and had the most recent healthcare visit coded as ‘uninsured’ were
identified in the baseline period. The five risk indices used were: the HHS Hierarchical
Conditions Category (HCC), the Charlson Comorbidity Index (CCI), Total Cost Index, Total
Inpatient Visits Index, and Total Emergency Department Visits Index. First, agreement
across the five indices was analyzed. Then, the accuracy of the five risk indices was
tested in predicting future utilization and costs for the subsequent 12-month follow-up
period.Results: Kappa statistics and percent overlap values showed below average to poor
agreement between indices when comparing scorers.The strongest predictors of being in
the 90th percentile of total cost during the 12 months follow-up period were the Total
Cost Index at baseline (C statistic=0.75) and the HCC (C-statistic=0.73). The CCI and
Total Inpatient Visit Index’s demonstrated the lowest accuracy for predicting an
unnecessary ED visit (C-statistic=0.51, for both)Discussion/Conclusion: Prior cost and
ED utilization were key in predicting their corresponding 12-month metrics. In contrast,
the Total Inpatient Visit Index had the worst predictive performance for future
hospitalization rates. Some indices were similarly predictive as compared to insured
cohorts but others showed contrasting results.
A Framework for Classification of Electronic Health Data
Extraction-Transformation-Loading Challenges in Data Network Participation
Authors: Ong Toan C. , Pradhananga Rosina , Holve Erin G. , Kahn Michael G.
Published: December 2017

Background: Contributing health data to national, regional, and local networks or
registries requires data stored in local systems with local structures and codes to be
extracted, transformed, and loaded into a standard format called a Common Data Model
(CDM). These processes called Extract, Transform, Load (ETL) require data partners or
contributors to invest in costly technical resources with specialized skills in data
models, terminologies, and programming. Given the wide range of tasks, skills, and
technologies required to transform data into a CDM, a classification of ETL challenges
can help identify needed resources, which in turn may encourage data partners with
less-technical capabilities to participate in data-sharing networks.Methods: We
conducted key-informant interviews with data partner representatives to survey the ETL
challenges faced in clinical data research networks (CDRNs) and registries. A list of
ETL challenges, organized into six themes was vetted during a one-day workshop with a
wide range of network stakeholders including data partners, researchers, and policy
experts.Results: We identified 24 technical ETL challenges related to the data sharing
process. All of these ETL challenges were rated as “important” or “very important” by
workshop participants using a five point Likert scale. Based on these findings, a
framework for categorizing ETL challenges according to ETL phases, themes, and levels of
data network participation was developed.Conclusions: Overcoming ETL technical
challenges require significant investments in a broad array of information technologies
and human resources. Identifying these technical obstacles can inform optimal resource
allocation to minimize the barriers and cost of entry for new data partners into extant
networks, which in turn can expand data networks’ inclusiveness and diversity. This
paper offers pertinent information and guiding framework that are relevant for data
partners in ascertaining challenges associated with contributing data in data
networks.