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The Playeur and Pokémon Go: Examining the effects of locative play on spatiality and sociability
Pokémon Go is a hugely popular hybrid reality game (HRG) that enables players to occupy a space that is simultaneously physical and digital. The general aim of Pokémon Go is to discover and then capture Pokémon. This article reports on an original research project designed to explore the impact of Pokémon Go on spatiality and sociability. The project was conducted between May 2017 and July 2017, using an online survey which received 375 responses from users of Pokémon Go geographically spread across the globe. Drawing on the concept of the ‘playeur’ as an established approach to understanding the effects of locative play on spatiality and sociability, this research follows three lines of enquiry. First, the research examines whether the intermingling of play and ordinary life might encourage players to spend more time outside in public spaces, and how this mode of play is experienced. Second, the research explores whether the game mechanics of Pokémon Go might lead players to traverse their environment using modified routes, as well as frequent new places. Third, the research examines whether the praxis of Pokémon Go might enable new forms of sociability to emerge that extend beyond earlier HRGs
Portable X‐ray fluorescence spectroscopy as a tool for cyclostratigraphy
Cyclostratigraphic studies are used to create relative and high‐resolution timescales for sedimentary successions based on identification of regular cycles in climate proxy data. This method typically requires the construction of long high‐resolution datasets. In this study, we have demonstrated the efficacy of portable X‐ray fluorescence spectroscopy (pXRF) as a non‐destructive method of generating compositional data for cyclostratigraphy. The rapidity (100 samples per day) and low cost of pXRF measurements provide advantages over relatively time‐consuming and costly elemental and stable isotopic measurements that are commonly used for cyclostratigraphy. The non‐destructive nature of pXRF also allows other geochemical analyses on the same samples. We present an optimized protocol for pXRF elemental concentration measurement in powdered rocks. The efficacy of this protocol for cyclostratigraphy is demonstrated through analysis of 360 Toarcian mudrock samples from North Yorkshire, UK, that were previously shown to exhibit astronomical forcing of [CaCO3], [S] and δ13Corg. Our study is the first to statistically compare the cyclostratigraphic results of pXRF analysis with more established combustion analysis. There are strong linear correlations of pXRF [Ca] with dry combustion elemental analyzer [CaCO3] (r2=0.7616), and pXRF [S] and [Fe] with dry combustion elemental analyzer [S] (r2=0.9632 and r2=0.9274 respectively). Spectral and cross‐spectral analysis demonstrates that cyclicity previously recognized in [S], significant above the 99.99% confidence level, is present above the 99.92% and 99.99% confidence levels in pXRF [S] and [Fe] data respectively. Cyclicity present in [CaCO3] data above the 99.96% confidence level is also present in pXRF [Ca] above the 98.12% confidence level
Distribution and toxicity of Cylindrospermopsis raciborskii (Cyanobacteria) in Portuguese freshwaters
The cyanobacterium Cylindrospermopsis racborskii has become increasingly prevalent in freshwaters worldwide. This species is of concern from a water quality perspective due to its known ability to produce a potent hepatotoxic alkaloid cylindrospermopsin, which has been implicated in outbreaks of human sickness and cattle mortality. C. raciborskii isolates from Brazil have also been found to produce the highly toxic paralytic shellfish poisons (PSP's). In this paper we report the toxicity of four isolates of C. raciborskii taken from three reservoirs and one river in Portugal as well as the occurrence of this species in other water bodies used for potable and recreational purposes. All four isolates grown in pure culture in the laboratory were found to be toxic in the mouse bioassay at 8 - 24 hours after intraperitoneal administration of single doses ranging from 1337 to 1572 mg kg-1. Histological examination showed liver damage as the primary lesion, in addition to some inflammation in the intestine. HPLC/MS tests for the presence of cylindrospermopsin, microcystins and PSP toxins were negative. The available evidence suggests that another toxin may be present. This report constitutes the first report of toxic C. raciborskii in Europe and draws attention to our need for increased monitoring of this cyanobacterium in water bodies used for potable and recreational purposes.La cianobacteria Cylindrospermopsis racborskii ha incrementado su presencia en agua dulce por todo el mundo. Esta especie es de gran importancia debido a su conocida capacidad para producir un alcaloide hepatotóxico, cilindrospermopsina. Esta toxina es responsable de enfermedades en humanos y mortalidad en ganado. Cepas de C. raciborskii aisladas de Brasil se ha demostrado que tienen capacidad para producir la toxina paralytic shellfish poisons (PSP's). En este trabajo hemos estudiado la presencia de esta especie en agua dulce con usos recreacionales y de abastecimiento en Portugal. De las cuatro cepas C. raciborskii aisladas de tres embalses y de un río estudiamos la toxicidad con bioensayos en ratones. Todas presentaron toxicidad al cabo de las 8 - 24 horas tras inyección intraperitoneal, la dosis presenta un rango de concentración de 1337 a 1572 mg kg-1. La examinación histológica reveló daños en el hígado y señales inflamatorias en el intestino. Los análisis con HPLC/MS revelaron la ausencia de cilindrospermopsina, microcistinas y PSP, sugiriendo que otra toxina podría estar presente para las cepas aisladas y cultivadas en laboratorio. Este artículo es el primero acerca de la toxicidad de C. raciborskii en Europa y refleja la necesidad de aumentar el monitoreo de esta cyanobacteria en el agua potable y con fines recreativos
Caracteristicas de discos debris en Enanas Blancas
Abstract: In the late ’80s an infrared excess (IR) around a white dwarf star (WD) was detected, which was attributed to the presence of a dusty circumstellar disk. In recent years, thanks to Spitzer, the number of WDs with excesses has increased significantly. In this contribution we present
the modeling of the spectral energy distributions (SEDs) of a sample of 29 WDs having IR excesses. This model allows us to derive the mass and the internal and external radii of the dusty disk, for a given chemical composition. The location of this ring is compared with the Habitability
Zone (HZ) of each WD in the sample. In addition, the dimensions and masses of these rings are compared with those around main sequence stars, commonly known in the literature as debris disks.Resumen: A finales de la década de 1980 se detectó exceso infrarrojo (IR) alrededor de una estrella enana blanca (EB), el cual fue atribuido a la presencia de un disco circunestelar de polvo. En los últimos años gracias a Spitzer se amplió el número de EBs con excesos IR. En este trabajo se presenta el modelado de las distribuciones espectrales de energía (SEDs) de una muestra de 29 EBs que presentan excesos. Este modelo permite derivar la masa, el radio interno y el radio externo de estos discos de polvo, para una dada composición química. Se compara la ubicación de estos anillos con la Zona de Habitabilidad (ZH) de cada EB en la muestra analizada. Ademas, las dimensiones y masas de estos anillos son comparadas con aquellos en estrellas de secuencia principal, comúnmente conocidos en la literatura como discos debris o de escombros.Fil:Gómez,Mercedes Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Chavero,Carolina Andrea Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina.http://www.astronomiaargentina.org.ar/b56/BAAA56_v15_final.pdfpublishedVersionAstronomía (incluye Astrofísica y Ciencias del Espacio
A configurational analysis of the termination scenarios of international joint ventures: all is well that ends well
This article analyzes termination in international joint ventures (IJVs) with a set theoretic approach and fuzzy set Qualitative Comparative Analysis (fsQCA) to show that parent contribution, ownership, managerial configuration and experience can lead to a successful end of a joint venture. The use of fsQCA provides the causal paths leading to termination. Termination by achieving the objectives and termination by corporate restructuring are the most common ways in IJVs to end the collaborative venture and are a consequence of the joint set of foreign contribution, ownership structure, managerial configuration and experience. The duration of terminated IJVs highlights the importance of managerial experience and local contribution
Stellar parameters and chemical abundances of 223 evolved stars with and without planets
We present fundamental stellar parameters and chemical abundances for a
sample of 86 evolved stars with planets and for a control sample of 137 stars
without planets. The analysis was based on both high S/N and resolution echelle
spectra. The goals of this work are i) to investigate chemical differences
between stars with and without planets; ii) to explore potential differences
between the properties of the planets around giants and subgiants; and iii) to
search for possible correlations between these properties and the chemical
abundances of their host stars. In agreement with previous studies, we find
that subgiants with planets are, on average, more metal-rich than subgiants
without planets by ~ 0.16 dex. The [Fe/H] distribution of giants with planets
is centered at slightly subsolar metallicities and there is no metallicity
enhancement relative to the [Fe/H] distribution of giants without planets.
Furthermore, contrary to recent results, we do not find any clear difference
between the metallicity distributions of stars with and without planets for
giants with M > 1.5 Msun. With regard to the other chemical elements, the
analysis of the [X/Fe] distributions shows differences between giants with and
without planets for some elements, particularly V, Co, and Ba. Analyzing the
planet properties, some interesting trends might be emerging: i) multi-planet
systems around evolved stars show a slight metallicity enhancement compared
with single-planet systems; ii) planets with a 0.5 AU orbit
subgiants with [Fe/H] > 0 and giants hosting planets with a 1 AU
have [Fe/H] < 0; iii) higher-mass planets tend to orbit more metal-poor giants
with M < 1.5 Msun, whereas planets around subgiants seem to follow the
planet-mass metallicity trend observed on dwarf hosts; iv) planets orbiting
giants show lower orbital eccentricities than those orbiting subgiants and
dwarfs.Comment: 49 pages, 31 figures, Accepted for publication in A&A, abstract
shortened - corrected references, typos, acknowledgements include
Benign paroxysmal positional vertigo after radiologic scanning: a case series
<p>Abstract</p> <p>Introduction</p> <p>Benign paroxysmal positional vertigo (BPPV) is the most common type of vertigo. It is frequently seen in elderly patients, and the course of the attack may easily mimic cerebrovascular disease. A BPPV attack after a radiologic examination has not been reported previously. We report the cases of two patients who had BPPV attacks after radiologic imaging.</p> <p>Case presentation</p> <p>The first patient with headache and tremor was admitted to the radiology department for cranial computed tomography (CT) imaging. During scanning, she was asked to lie in the supine position with no other head movements for approximately 10 minutes. After the cranial CT imaging, she stood up rapidly, and suddenly experienced a vertigo attack and nausea. The second patient was admitted to the radiology department for evaluation of his renal arteries. During the renal magnetic resonance angiography, he was in the supine position for 20 minutes and asked not to move. After the examination, he stood up rapidly with the help of the technician and suddenly experienced a vertigo attack with nausea and vomiting. The results of standard laboratory analyses and their neurologic examinations were within normal limits and Dix-Hallpike tests showed rotatory nystagmus in both cases. An Epley maneuver was performed to the patients. The results of a control Dix-Hallpike tests after 1 Epley maneuver were negative in both patients.</p> <p>Conclusion</p> <p>Radiologists and clinicians must keep in mind that after radiologic imaging in which the patient is still for some time in the supine position and then helped to stand up rapidly, a BPPV attack may occur.</p
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