bluuebunny/crossref_metadata_2025_split huggingface dataset:
Massage Therapy in Management of Occupational Stress in Emergency Medical Services Staffs: a Randomized Controlled Trial
Authors: Mahdizadeh, BSc Mahdi , Ansari Jaberi, MSc Ali , Negahban Bonabi, PhD Tayebeh 
Published: March 2019

Background: Results of various studies indicate that emergency medical service (EMS) staff suf-fer from occupational stress that adversely affects their quality of life and their care quality. Purpose: This study aimed at determining the ef-fect of massage on occupational stress experienced by emergency medical service staff. Setting: Prehospital emergency medical services stations of a city in the southwest of Iran.Participants: A total of 58 members of staff of the emergency medical services, working in prehospi-tal emergency medical services stations. Research Design: In this randomized controlled trial, a total of 58 EMS staff were selected from prehospital EMS stations, according to inclusion and exclusion criteria, and then assigned in two groups (29 in massage and 29 in control group) randomly by the minimization method. The inter-vention group received Swedish massage, twice a week for four weeks in the morning after the end of the work shift. Each massage session lasted 20–25 minutes. Subjects in the control group received no intervention. The level of occupational stress of the two groups was measured under the same condi-tions before and after the intervention by using the expanded nurses’ occupational stress scale (ENSS). Data were analyzed with the SPSS16 software by using the chi-squared test, paired and independent-sample t tests, one-way ANCOVA. P value < .05 was considered as the level of significance.Results: The mean and SD of total occupational stress scores in the control group was 114.41±30.11 in pretest and reach to 112.58± 30.62 in posttest stage. Also the mean and SD of total occupa-tional stress scores in the intervention group was 130.20±26.45 in pretest and reach to 110.41±21.75 in posttest stage. A one-way ANCOVA showed that there is a significant effect of massage on EMS staff’s occupational stress level after controlling for pretest score (p = .001).Conclusions: The training and the application of massage therapy can serve as an effective method in reducing occupational stress in emergency medical centers.
Benchmarking Substellar Evolutionary Models Using New Age Estimates for HD 4747 B and HD 19467 B
Authors: Wood Charlotte M. , Boyajian Tabetha , Braun Kaspar von , Brewer John M. , Crepp Justin R. , Schaefer Gail , Adams Arthur , White Timothy R. 
Published: March 2019

Abstract
Constraining substellar evolutionary models (SSEMs) is particularly difficult due to a degeneracy between the mass, age, and luminosity of a brown dwarf. In cases where a brown dwarf is found as a directly imaged companion to a star, as in HD 4747 and HD 19467, the mass, age, and luminosity of the brown dwarf are determined independently, making them ideal objects to use to benchmark SSEMs. Using the Center for High Angular Resolution Astronomy Array, we measured the angular diameters and calculated the radii of the host stars HD 4747 A and HD 19467 A. After fitting their parameters to the Dartmouth Stellar Evolution Database, MESA Isochrones and Stellar Tracks, and Yonsei-Yale isochronal models, we adopt age estimates of

Gyr for HD 4747 A and

Gyr for HD 19467 A. Assuming the brown dwarf companions HD 4747 B and HD 19467 B have the same ages as their host stars, we show that many of the SSEMs under-predict bolometric luminosities by ∼0.75 dex for HD 4747 B and ∼0.5 dex for HD 19467 B. The discrepancies in luminosity correspond to over-predictions of the masses by ∼12% for HD 4747 B and ∼30% for HD 19467 B. We also show that SSEMs that take into account the effect of clouds reduce the under-prediction of luminosity to ∼0.6 dex and the over-prediction of mass to ∼8% for HD 4747 B, an L/T transition object that is cool enough to begin forming clouds. One possible explanation for the remaining discrepancies is missing physics in the models, such as the inclusion of metallicity effects.
Unified Quantitative Description of Solar Wind Turbulence Intermittency in Both Inertial and Kinetic Ranges
Authors: He Jiansen , Wang Ying , Sorriso-Valvo Luca 
Published: March 2019

Abstract
There are various ways of describing intermittent features in space plasma turbulence, but we lack a unified paradigm to connect the results from these different approaches. In this work, we aim to construct a unified paradigm to describe various intermittency-related quantities with the same set of parameters. The Castaing function, which describes the scale-dependent turbulence amplitude as a logarithmic normal distribution, is adopted as a fitting function to describe the probability distribution of magnetic field difference at various timescales τ. Two fitting parameters (μ, λ) as a function of τ are obtained and regarded as the fundamental information, based on which various characteristics related to intermittency can be derived at one time, e.g., the high-order structure functions, their scaling exponent as a function of the order, or the flatness as a function of τ. We find it is the derivative ratio, DR =

, that determines the order trend of the scaling exponent ζ(m). A negative DR of a small absolute is responsible for a curved ζ(m) in the inertial range, and a large positive DR leads to a straight ζ(m) in the kinetic range. Therefore, it is suggested that the probability distribution function of the magnetic increments spreads in width (λ(τ)) with decreasing τ in the inertial range, while it is saturated and even slightly reduced in the kinetic range. Moreover, it is found that the turnings between the inertial and kinetic scales for the two Castaing fitting parameters μ(τ) and λ
2(τ) occur at different scales: lnτ ∼ 0 and lnτ ∼ 2, respectively. The reason for this different behavior is still unclear.
Investigating the Transition Region Explosive Events and Their Relationship to Network Jets
Authors: Chen Yajie , Tian Hui , Huang Zhenghua , Peter Hardi , Samanta Tanmoy 
Published: March 2019

Abstract
Recent imaging observations with the Interface Region Imaging Spectrograph (IRIS) have revealed prevalent intermittent jets with apparent speeds of 80–250 km s−1 from the network lanes in the solar transition region (TR). Additionally, spectroscopic observations of the TR lines have revealed the frequent presence of highly non-Gaussian line profiles with enhanced emission at the line wings, often referred to as explosive events (EEs). Using simultaneous imaging and spectroscopic observations from IRIS, we investigate the relationship between EEs and network jets. We first identify EEs from the Si iv 1393.755 Å line profiles in our observations, then examine related features in the 1330 Å slit-jaw images. Our analysis suggests that EEs with double peaks or enhancements in both wings appear to be located at either the footpoints of network jets or transient compact brightenings. These EEs are most likely produced by magnetic reconnection. We also find that EEs with enhancements only at the blue wing are mainly located on network jets, away from the footpoints. These EEs clearly result from the superposition of the high-speed network jets on the TR background. In addition, EEs showing enhancement only at the red wing of the line are often located around the jet footpoints, which is possibly caused by the superposition of reconnection downflows on the background emission. Moreover, we find some network jets that are not associated with any detectable EEs. Our analysis suggests that some EEs are related to the birth or propagation of network jets, and that others are not connected to network jets.
Evolution of the Stellar Mass Function and Infrared Luminosity Function of Galaxies since z = 1.2
Authors: Beare Richard , Brown Michael J. I. , Pimbblet Kevin , Taylor Edward N. 
Published: March 2019

Abstract
We measured evolution of the K-band luminosity function and stellar mass function (SMF) for red and blue galaxies at z < 1.2 using a sample of 353 594 I < 24 galaxies in 8.26 square degrees of Boötes. We addressed several sources of systematic and random error in measurements of total galaxy light, photometric redshift, and absolute magnitude. We have found that the K-band luminosity density for both red and blue galaxies increased by a factor of 1.2 from z ∼ 1.1 to z ∼ 0.3, while the most luminous red (blue) galaxies decreased in luminosity by 0.19(0.33) mag or ×0.83(0.74). These results are consistent with z < 0.2 studies, while our large sample size and area result in smaller Poisson and cosmic variance uncertainties than most z > 0.4 luminosity and mass function measurements. Using an evolving relation for K-band mass-to-light ratios as a function of (B−V) color, we found a slowly decreasing rate of growth in red galaxy stellar mass density of ×2.3 from z ∼ 1.1 to z ∼ 0.3, indicating a slowly decreasing rate of migration from the blue cloud to the red sequence. Unlike some studies of the SMF, we find that massive red galaxies grow by a factor of ×1.7 from z ∼ 1.1 to z ∼ 0.3, with the rate of growth due to mergers decreasing with time. These results are comparable with measurements of merger rates and clustering, and they are also consistent with the red galaxy stellar mass growth implied by comparing K-band luminosity evolution with the fading of passive stellar population models.
The Wolf–Rayet Stellar Response To The Iron Opacity Bump: Envelope Inflation, Winds, and Microturbulence
Authors: Ro Stephen 
Published: March 2019

Abstract
Early-type Wolf–Rayet (WR) stellar models harbor a super-Eddington layer in their outer envelopes due to a prominent iron opacity bump. In the past few decades, one-dimensional hydrostatic and time-steady hydrodynamic models have suggested a variety of WR responses to a super-Eddington force including envelope inflation and optically thick winds. In this paper, I study these responses using semianalytical estimates and WR models from both MESA and Ro & Matzner; four conclusions are present. First, early-type WR stars do not harbor inflated envelopes because they have either strong winds or insufficient luminosities. Second, the condition for an opacity bump to harbor a sonic point is expressible as a minimum mass-loss rate,

. In agreement with Grassitelli et al. and Ro, the majority of galactic early-type WR stars can harbor sonic points at the iron opacity bump. However, about half of those in the Large Magellanic Cloud cannot given typical wind parameters. Third, WR winds driven by the iron opacity bump must have mass-loss rates that exceed a global minimum of 10−5.8–10−6

yr

. Lastly, the observed early-type WR distribution follows a simple mass-loss relation derived here if the radiation-to-gas pressure ratio is approximately p

r
/p

g
≃ 145 in the wind; a value consistent with studies by Gräfener et al. and Nakauchi & Saio.
Magnetic Field Dynamics and Varying Plasma Emission in Large-scale Coronal Loops
Authors: Şahin S. , Yurchyshyn V. , Kumar P. , Kilcik A. , Ahn K. , Yang X. 
Published: March 2019

Abstract
In this study we report detailed observations of magnetic environment at four footpoints of two warm coronal loops observed on 2016 May 5 in NOAA AR 12542 (Loop I) and 2015 December 17 in NOAA AR 12470 (Loop II). These loops were connecting a plage region with sunspot periphery (Loop I) and a sunspot umbra (Loop II). We used Solar Dynamics Observatory (SDO) and Goode Solar Telescope (GST) data to describe the phenomenon and understand its causes. The study indicates loop brightening episodes were associated with magnetic flux emergence and cancellation processes observed in SDO’s Helioseismic and Magnetic Imager and GST’s Near InfraRed Imaging Spectrapolarimeter data. The observed activity was driven by magnetic reconnection between small-scale emerging dipoles and large-scale pre-existing fields, suggesting that the reconnection occurred in the lower chromosphere at the edge of an extended plage region, where the loops were rooted. We suggest that plasma, evaporated during these reconnection events, gradually filled the loops and as it cooled the visible density front propagated from one footpoint of the loop to another at a rate of 90–110 km s−1. This study also indicates that at least some of the bright loops seen in SDO Atmospheric Imaging Assembly images rooted in sunspot umbra may be heated due to magnetic activity taking place at the remote (nonsunspot) footpoint.
Star Formation Stochasticity Measured from the Distribution of Burst Indicators
Authors: Broussard Adam , Gawiser Eric , Iyer Karthiek , Kurczynski Peter , Somerville Rachel S. , Davé Romeel , Finkelstein Steve , Jung Intae , Pacifici Camilla 
Published: March 2019

Abstract
One of the key questions in understanding galaxy formation and evolution is how starbursts affect the assembly of stellar populations in galaxies over time. We define a burst indicator (η) that compares a galaxy’s star formation rates (SFRs) on short (∼10 Myr) and long (∼100 Myr) timescales. To estimate η, we apply the detailed time-luminosity relationship for Hα and near-ultraviolet emission to simulated star formation histories (SFHs) from semi-analytic models and the Mufasa hydrodynamical cosmological simulations. The average of η is not a good indicator of star formation stochasticity (burstiness); indeed, we show that this average should be close to zero unless the galaxy population has an average SFH that is rising or falling rapidly. Instead, the width of the η distribution characterizes the burstiness of a galaxy population’s recent star formation. We find this width to be robust to variations in stellar initial mass function and metallicity. We apply realistic noise and selection effects to the models to generate mock Hubble Space Telescope (HST) and James Webb Space Telescope (JW
ST) galaxy catalogs and compare these catalogs with 3D-HST observations of 956 galaxies at 0.65 < z < 1.5 detected in Hα. Measurements of η are unaffected by dust measurement errors under the assumption that E(B − V)stars = 0.44 E(B − V)gas (i.e., Q
sg = 0.44). However, setting

removes an unexpected dependence of the average value of η upon dust attenuation and stellar mass in the 3D-HST sample while also resolving disagreements in the distribution of SFRs. However, even varying the dust law cannot resolve all discrepancies between the simulated and the observed galaxies.
Predicting the X-Ray Spectra of Stellar-mass Black Holes from Simulations
Authors: Kinch Brooks E. , Schnittman Jeremy D. , Kallman Timothy R. , Krolik Julian H. 
Published: March 2019

Abstract
We describe results from a new technique for the prediction of complete, self-consistent X-ray spectra from three-dimensional general relativistic magnetohydrodynamic (GRMHD) simulations of black hole accretion flows. Density and cooling rate data from a harm3d GRMHD simulation are post-processed by an improved version of the Monte Carlo radiation transport code pandurata (in the corona) and the Feautrier solver ptransx (in the disk), with xstar subroutines. The codes are run in a sequential, iterative fashion to achieve globally energy-conserving and self-consistent radiation fields, temperature maps, and photoionization equilibria. The output is the X-ray spectrum as seen by a distant observer, including features, such as the Fe Kα emission line and corresponding K-edge absorption trough, due to disk reprocessing of coronal power. For the example cases we consider—a non-rotating 10 M
⊙ black hole with solar abundances, accreting at 0.01, 0.03, 0.1, or 0.3 Eddington—we find spectra resembling actual observations of stellar-mass black holes in the soft or steep power-law state: broad thermal peaks (at 1–3 keV), steep power laws extending to high energy (Γ = 2.7–4.5), and prominent, asymmetric Fe Kα emission lines with equivalent widths in the range 40–400 eV (larger EW at lower accretion rates). By starting with simulation data, we obviate the need for parameterized descriptions of the accretion flow geometry—no a priori specification of the corona’s shape or flux, or the disk temperature or density, etc., is needed. Instead, we apply the relevant physical principles to simulation output using appropriate numerical techniques; this procedure allows us to calculate inclination-dependent spectra after choosing only a small number of physically meaningful parameters: black hole mass and spin, accretion rate, and elemental abundances.
Magnetic Field of the Eclipsing M-dwarf Binary YY Gem
Authors: Kochukhov Oleg , Shulyak Denis 
Published: March 2019

Abstract
YY Gem is a short-period eclipsing binary system containing two nearly identical, rapidly rotating, very active early M dwarfs. This binary represents an important benchmark system for calibrating empirical relations between fundamental properties of low-mass stars and for testing theories of interior structure and evolution of these objects. Both components of YY Gem exhibit inflated radii, which has been attributed to poorly understood magnetic activity effects. Despite a long history of magnetic activity studies of this system, no direct magnetic field measurements have been made for it. Here we present a comprehensive characterization of the surface magnetic field in both components of YY Gem. We reconstructed the global field topologies with the help of a tomographic inversion technique applied to high-resolution spectropolarimetric data. This analysis revealed moderately complex global fields with a typical strength of 200–300 G and anti-aligned dipolar components. A complementary Zeeman intensification analysis of the disentangled intensity spectra showed that the total mean field strength reaches 3.2–3.4 kG in both components of YY Gem. We used these results together with other recent magnetic field measurements of M dwarfs to investigate the relation between the global and small-scale fields in these stars. We also assessed predictions of competing magnetoconvection interior structure models developed for YY Gem, finding that only one of them anticipated the surface field strength compatible with our observations. Results of our starspot mapping of YY Gem do not support the alternative family of theoretical stellar models, which attempts to explain the radius inflation by postulating a large spot filling factor.
Stream benthic macroinvertebrates abundances over a 6-year monitoring period of an Italian glacier-fed stream
Authors: Scotti Alberto , Tappeiner Ulrike , Bottarin Roberta 
Published: March 2019

Aquatic macroinvertebrates are widely used as bioindicators for water quality assessments involving different kinds of disruptive factors, such as hydrological regime variations or pollutant spills. Recently, they demonstrated to be effective in monitoring effects of climate change in alpine stream and rivers. Indeed, since the distribution of macroinvertebrates in glacier-fed streams has been succesfully investigated and described by several authors, the discrepancy in presence/absence and quantity of specific taxa from the established models may represent an early warning of the effects of climatic changes occurring in alpine riverine ecosystems.
Together with the present paper, we provide a dataset covering a period of 6 years (2010-2015) sampling of aquatic macroinvertebrates along a longitudinal transect of a glacier-fed stream located in the Italian Alps, inside the International Long Term Ecological Research (ILTER) macrosite of Matsch|Mazia (IT-25). Data were collected during the glacial melt period (April - September), with monthly resolution. Owing to the unique temporal resolution of the dataset, we aim to produce a reliable tool (i.e. reference point) for future ecological assessment on the same stream, but also to similar streams worldwide.
Développement rural en Afrique tropicale et diffusion du numérique, une approche géographique
Authors: Bart Françoise , Lesourd Michel 
Published: March 2019

Ce texte a pour objectif de montrer l’importance des TIC (numérique) pour le développement rural en Afrique. Il développe quelques exemples, en particulier au Rwanda, au Cap Vert et en Tanzanie ; il insiste à la fois sur les grandes potentialités et sur les laissés pour compte de la société de l’information.
Les technologies numériques dans les pays en développement. Quel paradigme ?
Authors: Dahmani Ahmed 
Published: March 2019

Les technologies numériques constituent l’innovation majeure de ces dernières décennies et le principal vecteur de la nouvelle révolution industrielle dans les pays développés. Ces technologies ont radicalement transformé les modes de vie, les façons de produire, les rapports au temps et à l’espace, l’environnement culturel. Quid alors des pays en développement, notamment africains, où ces technologies connaissent une progression fulgurante. Quels sont leurs différents impacts dans ces pays où leur progression dépasse toutes les prévisions. Comment les différents usages et les capacités d’appropriation manifestés par les sociétés africaines nous interpellent pour réfléchir à un nouveau paradigme qui tienne compte de toutes les mutations et changements socioéconomiques et culturels que ces technologies provoquent ?
Le numérique, pour coopérer en formation à distance
Authors: Racette Nicole , Bourdages-Sylvain Marie-Pierre 
Published: March 2019

Dans une recherche menée dans quatre établissements d’enseignement, nous abordons la question suivante : comment le numérique contribue- t-il ou limite-t-il la coopération entre les équipes de conception et les équipes d’encadrement ? À partir de 44 entrevues individuelles et 8 entrevues de groupes, les résultats montrent que ces équipes, éloignées physiquement, se rencontrent très peu et utilisent majoritairement le courriel pour communiquer, outil que nous considérons permettre surtout le transfert des connaissances plutôt que les échanges, et ce, à partir des caractéristiques rapportées par les répondants. Ainsi, lorsque les courriels sont utilisés pour échanger, ils sont susceptibles d’engendrer des dysfonctionnements dans les relations. Les outils d’échange (forums, visioconférences, etc.) sont très peu utilisés. L’emploi des outils de développement des connaissances (logiciels de formation, etc.) est fortement souhaité par les tuteurs répondants, bien que ces derniers réclament surtout des rencontres en face à face pour créer d’abord une relation, afin de permettre de mieux coopérer et améliorer ainsi la qualité de leur travail.