bluuebunny/crossref_metadata_2025 huggingface dataset:
Experience with Prophylactic Gentamicin During Penile Prosthesis Surgery: A Retrospective Comparison of Two Different Doses
Authors: Xie Donghua , Gheiler Victor , Lopez Isabel , Nehrenz Guy M. , Klopukh Boris , Bianco Fernando , Perito Paul , Gheiler Edward
Published: July 2017

Background

Gentamicin has been determined to be active against a wide range of bacterial infections and has been commonly used as a preoperative antibiotic for inflatable penile prosthesis (IPP) implantation. However, the best dosing regimen to produce the safest optimal prophylactic effect remains to be determined.

Aim

To compare low- and high-dose gentamicin as prophylaxis during IPP implantation.

Methods

We retrospectively analyzed two groups of patients who underwent IPP placement from April 14, 2012 through April 13, 2016. Group 1 was composed of 490 patients who underwent IPP placement from April 14, 2012 through April 13, 2014 and received a low dose of preoperative gentamicin at 80 mg every 8 hours for 1 day. Group 2 was composed of 407 patients who underwent IPP placement from April 14, 2014 through April 13, 2016 and received a single high dose of preoperative gentamicin at 5 mg/kg. We compared the infection rates of IPP and any gentamicin-related toxicities. The same surgeon performed all procedures. All patients received additional vancomycin 1 g before incision and at 12 hours postoperatively.

Outcome

Demographic data and IPP infection rate were compared and potential toxicities from the higher dose of gentamicin were closely monitored.

Results

There were no significant differences in mean age, mean body mass index, and mean interval for IPP placement and IPP infection between the two groups. No toxicity was seen with the higher gentamicin dose. Six cases in group 1 (five de novo cases and one redo case, infection rate = 1.22%) and three cases in group 2 (two de novo cases and one redo case, infection rate = 0.74%) were found to have IPP infection. The infection rate in group 2 appeared to be lower than that in group 1, although a significant statistical difference was not achieved (P = .057).

Clinical Implications

These findings would help guide urologists in choosing an optimal preoperative gentamicin dose for IPP surgery.

Strengths and Limitations

This is the first study to report on the usage of high-dose preoperative gentamicin for IPP surgery but with limitations as a retrospective study.

Conclusions

Although not achieving a statistical difference, there was a trend for patients receiving a higher dose of preoperative gentamicin to have a lower IPP infection rate. No toxicity was encountered from the 5-mg/kg gentamicin dose. We recommend following prophylactic high-dose gentamicin guidelines.
Candidates and Voters
Authors: Stone Walter J.
Published: July 2017

Candidates and Voters extends our understanding of voting, elections, and representation by elaborating a simple theory of voting choice based on voters' interest in policy and in the suitability of candidates to hold elective office ('leadership valence'). Voters' choices must be understood in the context of the choices between opposing candidates they are offered on these two dimensions. Drawing on extensive analysis of US House races, Stone shows that although voters lack the information that many analysts assume they need to function in a democracy, they are most often able to choose the better candidate on the policy and valence dimensions. In addition, candidates, when they decide whether and how to run, anticipate the interests that drive voters. The book shows that elections tend to produce outcomes on policy and leadership valence consistent with voters' interests, and challenges skeptical views of how well the electoral process works.
Approximate number sense theory or approximate theory of magnitude?
Authors: Content Alain , Velde Michael Vande , Adriano Andrea
Published: July 2017

Leibovich et al. argue that the evidence in favor of a perceptual mechanism devoted to the extraction of numerosity from visual collections is unsatisfactory and propose to replace it with an unspecific mechanism capturing approximate magnitudes from continuous dimensions. We argue that their representation of the evidence is incomplete and that their theoretical proposal is too vague to be useful.
Why try saving the ANS? An alternative proposal
Authors: Gebuis Titia , Cohen Kadosh Roi , Gevers Wim
Published: July 2017

Leibovich et al. propose that continuous magnitudes and a number sense are used holistically to judge numerosity. We point out that their proposal is incomplete and implausible: incomplete, as it does not explain how continuous magnitudes are calculated; implausible, as it cannot explain performance in estimation tasks. We propose that we do not possess a number sense. Instead, we assume that numerosity judgments are accomplished by weighing the different continuous magnitudes constituting numerosity.
Infants discriminate number: Evidence against the prerequisite of visual object individuation and the primacy of continuous magnitude
Authors: Libertus Melissa E. , Braham Emily J. , Liu Ruizhe
Published: July 2017

Leibovich et al. hypothesize that the absence of visual object individuation limits infants' numerical skills and necessitates a reliance on continuous magnitudes. We argue that parallels between infants' numerical discrimination in the visual and auditory modalities, their abilities to match numerosities across modalities, and their greater ability to discriminate changes in number compared with continuous magnitudes contradict the authors' assumptions.
Infants, animals, and the origins of number
Authors: Margolis Eric
Published: July 2017

Where do human numerical abilities come from? Leibovich et al. argue against nativist views of numerical development noting limitations in newborns' vision and limitations regarding newborns' ability to individuate objects. I argue that these considerations do not undermine competing nativist views and that Leibovich et al.'s model itself presupposes that infant learners have numerical representations.
Commentary on Leibovich et al.: What next?
Authors: Mix Kelly S. , Newcombe Nora S. , Levine Susan C.
Published: July 2017

The conclusions reached by Leibovich et al. urge the field to regroup and consider new ways of conceptualizing quantitative development. We suggest three potential directions for new research that follow from the authors' extensive review, as well as building on the common ground we can take from decades of research in this area.
Innateness of magnitude perception? Skill can be acquired and mastered at all ages
Authors: Rubinsten Orly , Karni Avi
Published: July 2017

We agree with Leibovich et al.'s argument that the number sense theory should be re-evaluated. However, we argue that highly efficient skills (i.e., fluent and highly accurate, “automatic,” performance) can be acquired and mastered at all ages. Hence, evidence for primacy or fluency in perceiving continuous magnitudes is insufficient for supporting strong conclusions about the innateness of this aptitude.
From continuous magnitudes to symbolic numbers: The centrality of ratio
Authors: Sidney Pooja G. , Thompson Clarissa A. , Matthews Percival G. , Hubbard Edward M.
Published: July 2017

Leibovich et al.'s theory neither accounts for the deep connections between whole numbers and other classes of number nor provides a potential mechanism for mapping continuous magnitudes to symbolic numbers. We argue that focusing on non-symbolic ratio processing abilities can furnish a more expansive account of numerical cognition that remedies these shortcomings.
The Use of Interpreters in Medical Triage during a Refugee Mass-Gathering Incident in Europe
Authors: Alexakis Lykourgos Christos , Papachristou Anastasia , Baruzzi Chiara , Konstantinou Angeliki
Published: July 2017

Introduction

During a refugees’ mass-gathering incident in Kos Island, Greece, Médecins Sans Frontières (MSF; Brussels, Belgium) teams provided emergency medical care. A case report of the event focusing on difficulties encountered by the interpreters during triage and emergency response was prepared.

Methods

Data collected during the event were reviewed from the patient’s register and qualitative interviews were obtained from the MSF interpreters involved in the response. In addition, a description of the event and a literature review were included.

Results

Total consultations were 49 patients, mainly from Syria, with an average age of 25 years. During triage, 20 patients were tagged green with only minor injuries; 11 patients were tagged yellow, mostly due to heat exhaustion, but also a hypertensive crisis, a diabetic, a pregnant woman with abdominal pain, and a peptic ulcer exacerbation. The remaining 18 patients were tagged red and diagnosed with heat syncope, except from a case of epileptic seizures and an acute chest pain patient. Interpreters were insufficient in number to accompany each doctor and every nurse providing care during the event. In addition, they were constantly disturbed by both refugees and fellow medical team members demanding their service. Interpreters had to triage and prioritize where to go and for whom to interpret.

Conclusion

Interpreters are an integral part of a proper refugee reception system. They should be included in authorities planning where mass gatherings of refugees are expected. Appropriate training may be needed for interpreters to develop skills useful in mass gatherings and similar prehospital settings in order to better coordinate with the medical team.

AlexakisLCPapachristouABaruzziCKonstantinouA. The use of interpreters in medical triage during a refugee mass-gathering incident in Europe. Prehosp Disaster Med. 2017;32(6):684–687.
FASTWIND reloaded: Complete comoving frame transfer for “all” contributing lines
Authors: Puls Joachim
Published: July 2017

FASTWIND is a unified NLTE atmosphere/spectrum synthesis code originally designed (and frequently used) for the optical/IR spectroscopic analysis of massive stars with winds. Until the previous version (v10), the line transfer for background elements (mostly from the iron-group) was performed in an approximate way, by calculating the individual line-transitions in a single-line Sobolev or comoving frame approach, and by adding up the individual opacities and source functions to quasi-continuum quantities that are used to determine the radiation field for the complete spectrum (see Puls et al. 2005, A&A 435, 669, and updates).

We have now updated this approach (v11) and calculate, for all contributing lines (from elements H to Zn), the radiative transfer in the comoving frame, thus also accounting for line-overlap effects in an “exact” way. Related quantities such as temperature, radiative acceleration and formal integral have been improved in parallel. For a typical massive star atmospheric model, the computation times (from scratch, and for a modern desktop computer) are 1.5 h for the atmosphere/NLTE part, and 30 to 45 minutes (when not parallelized) for the formal integral (i.e., SED and normalized flux) in the ranges 900 to 2000 and 3800 to 7000 Å(Δλ = 0.03 Å).

We compare our new with analogous results from the alternative code CMFGEN (Hillier & Miller 1998, ApJ 496, 407, and updates), for a grid consisting of 5 O-dwarf and 5 O-supergiant models of different spectral subtype. In most cases, the agreement is very good or even excellent (i.e., for the radiative acceleration), though also certain differences can be spotted. A comparison with results from the previous, approximate method shows equally good agreement, though also here some differences become obvious. Besides the possibility to calculate the (total) radiative acceleration, the new FASTWIND version will allow us to investigate the UV-part of the spectrum in parallel with the optical/IR domain.
4-D Imaging and Modeling of Eta Carinae’s Inner Fossil Wind Structures
Authors: Madura Thomas I. , Gull Theodore , Teodoro Mairan , Clementel Nicola , Corcoran Michael , Damineli Augusto , Groh Jose , Hamaguchi Kenji , Hillier D. John , Moffat Anthony , Richardson Noel , Weigelt Gerd , Lindler Don , Feggans Keith
Published: July 2017

Eta Carinae is the most massive active binary within 10,000 light-years and is famous for the largest non-terminal stellar explosion ever recorded. Observations reveal that the supermassive (~120 M⊙) binary, consisting of an LBV and either a WR or extreme O star, undergoes dramatic changes every 5.54 years due to the stars’ very eccentric orbits (e ≈ 0.9). Many of these changes are caused by a dynamic wind-wind collision region (WWCR) between the stars, plus expanding fossil WWCRs formed one, two, and three 5.54-year cycles ago. The fossil WWCRs can be spatially and spectrally resolved by the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS). Starting in June 2009, we used the HST/STIS to spatially map Eta Carinae’s fossil WWCRs across one full orbit, following temporal changes in several forbidden emission lines (e.g. [Feiii] 4659 Å, [Feii] 4815 Å), creating detailed data cubes at multiple epochs. Multiple wind structures were imaged, revealing details about the binary’s orbital motion, photoionization properties, and recent (~5 − 15 year) mass-loss history. These observations allow us to test 3-D hydrodynamical and radiative-transfer models of the interacting winds. Our observations and models strongly suggest that the wind and photoionization properties of Eta Carinae’s binary have not changed substantially over the past several orbital cycles. They also provide a baseline for following future changes in Eta Carinae, essential for understanding the late-stage evolution of this nearby supernova progenitor. For more details, see Gull et al. (2016) and references therein.
Multi-messenger signals from core-collapse supernovae
Authors: Nakamura Ko , Horiuchi Shunsaku , Tanaka Masaomi , Hayama Kazuhiro , Takiwaki Tomoya , Kotake Kei
Published: July 2017

The next Galactic supernova is expected to bring great opportunities for the direct detection of gravitational waves, full flavor neutrinos, and multi-wavelength photons. To prepare for appropriate observations of these multi-messenger signals, we use a long-term numerical simulation of the core-collapse supernova and discuss detectability of the signals in different situations. By exploring the sequential multi-messenger signals of a nearby CCSN, we discuss preparations for maximizing successful studies of such an unprecedented stirring event.
The potential of using KMOS for multi-object massive star spectroscopy
Authors: Wegner Michael , Bender Ralf , Sharples Ray ,   the KMOS Team
Published: July 2017

KMOS, the “K-Band Multi-Object Spectrometer”, was built by a British-German consortium as a second generation instrument for the ESO Paranal Observatory. It is available to the user community since its successful commissioning in 2013 (Sharples et al. 2013). As a multi-object integral field spectrometer for the near infrared, KMOS offers 24 deployable IFUs of 2.8x2.8 arcsec and 14x14 spatial pixels each, which can either be placed individually within a 7.2 arcmin field of view or combined in a Mosaic mode in order to map contiguous fields on sky. The instrument covers the whole range of NIR atmospheric windows (0.8. . .2.5μm) with 5 spectral bands and a resolution of R ≈ 3000. . .4000.

Although the main science driver for KMOS was to enable the study of galaxy formation and evolution through multiplexed observations of high-redshift galaxies, KMOS also already exhibited its tremendous potential for the spectroscopy of massive stars: A quantitative study of 27 RSGs in NGC 300 (Gazak et al. 2015) proves its applicability for the spectroscopy of individual stars even beyond the Local Group. A Mosaic observation of the Galactic centre (Feldmeier-Krause et al. 2015) demonstrates how spectra of early-type stars can be extracted from a contiguous field. Other applications include (but need not be limited to) velocity determinations of globular cluster stars, observations of jets/outflows of high mass protostars, or contiguous mapping of star-forming regions.

We therefore aim at presenting the excellent capabilities of KMOS to a wider community and indicate potential applications.
Stellar and wind parameters of massive stars from spectral analysis
Authors: Araya Ignacio , Curé Michel
Published: July 2017

The only way to deduce information from stars is to decode the radiation it emits in an appropriate way. Spectroscopy can solve this and derive many properties of stars. In this work we seek to derive simultaneously the stellar and wind characteristics of a wide range of massive stars. Our stellar properties encompass the effective temperature, the surface gravity, the stellar radius, the micro-turbulence velocity, the rotational velocity and the Si abundance. For wind properties we consider the mass-loss rate, the terminal velocity and the line–force parameters α, k and δ (from the line–driven wind theory). To model the data we use the radiative transport code Fastwind considering the newest hydrodynamical solutions derived with Hydwind code, which needs stellar and line–force parameters to obtain a wind solution. A grid of spectral models of massive stars is created and together with the observed spectra their physical properties are determined through spectral line fittings. These fittings provide an estimation about the line–force parameters, whose theoretical calculations are extremely complex. Furthermore, we expect to confirm that the hydrodynamical solutions obtained with a value of δ slightly larger than ~ 0.25, called δ-slow solutions, describe quite reliable the radiation line-driven winds of A and late B supergiant stars and at the same time explain disagreements between observational data and theoretical models for the Wind–Momentum Luminosity Relationship (WLR).
The Progenitor-Remnant Connection of Neutrino-Driven Supernovae Across the Stellar Mass Range
Authors: Ertl Thomas
Published: July 2017

We perform hydrodynamic supernova (SN) simulations in spherical symmetry for progenitor models with solar metallicity across the stellar mass range from 9.0 to 120 M⊙ to explore the progenitor-explosion and progenitor-remnant connections based on the neutrino-driven mechanism. We use an approximative treatment of neutrino transport and replace the high-density interior of the neutron star (NS) by an inner boundary condition based on an analytic proto-NS core-cooling model, whose free parameters are chosen to reproduce the observables of SN 1987A and the Crab SN for theoretical models of their progenitor stars.

Judging the fate of a massive star, either a neutron star (NS) or a black hole (BH), solely by its structure prior to collapse has been ambiguous. Our work and previous attempts find a non-monotonic variation of successful and failed supernovae with zero-age main-sequence mass. We identify two parameters based on the “critical luminosity” concept for neutrino-driven explosions, which in combination allows for a clear separation of exploding and non-exploding cases.

Continuing our simulations beyond shock break-out, we are able to determine nucleosynthesis, light curves, explosion energies, and remnant masses. The resulting NS initial mass function has a mean gravitational mass near 1.4 M⊙. The average BH mass is about 9 M⊙ if only the helium core implodes, and 14 M⊙ if the entire pre-SN star collapses. Only ~10% of SNe come from stars over 20 M⊙, and some of these are Type Ib or Ic.
The Next Possible Outburst of P Cygni
Authors: Kochiashvili Nino , Beradze Sopia , Kochiashvili Ia , Natsvlishvili Rezo , Vardosanidze Manana
Published: July 2017

On the basis of long-term UBV observations of P Cygni, which were made by Eugene Kharadze and Nino Magalashvili between 1951-1983, is evident that P Cygni undergone reddening during those observations. P cygni is a LBV and a supernova impostor. Corrected on the reddening B-V color has values between about -0.4 (at the beginning of 1950-ies) and -0.1 (for the 1980-ies). It means that the star probably had earlier spectral type at the beginning of 20-th century and accordingly, we are witnesses of its evolutionary changes. It means also that on the HR diagram the star moves gradually to the instability strip of LBVs in Outburst. So, if the rate of the reddening of the P Cygni will the same in near future then the star will have the next eruption (or even supernova explosion) after approximately 80-120 years.

The long (approximately 1500 d, 1160 d, 760 d, 580 d) quasi-periods and the shorter ones (approximatelly 130 d, 68 d and 15-18 days) were revealed using the above observations.

We observed P Cygni on July 23 - October 20, 2014 with the 48 cm Cassegrain telescope and standard B,V,R,I filters. HD 228793 has been used as a comparison star. We revealed that during our observations the star underwent light variations with the mean amplitude of approximately 0.1 magnitudes in all pass-bands and the period of this change was approximately 68 days. There is also a relation between brightness and the Hα EW variability. Therefore, we think that the cause of this behavior may be a variability of rate of the stellar wind that is very strong in this star. Changes in the rate of the stellar wind, on the other hand, maybe due to the pulsation of the star. It seems that quasi-periods of the brightness variability are almost the exact multiples of each other which probably also indicates on pulsation of the star. According to the new photometric observations of 2014 the star continues reddening.
Red supergiant stars in NGC 4449, NGC 5055, and NGC 5457
Authors: Chun Sang-Hyun , Sohn Yong-Jong , Asplund Martin , Casagrande Luca
Published: July 2017

Nearby galaxies are ideal objects for the study of the mechanisms of galaxy formation and evolution, and massive stars in nearby galaxies are useful sources to investigate the structures and formation of the galaxies. It is important to gather the contents of massive stars for a number of galaxies spanning various metallicities. We focus on the red supergiants (RSGs) in nearby galaxies NGC 4449, NGC 5055, and NGC 5457, and the photometric properties of RSGs of three galaxies were investigated using near-infrared (JHK) imaging data obtained from WFCAM UKIRT. The (J − K, K)0 CMDs are investigated and compared with theoretical isochrones (Figure 1). The majority of RSGs in three galaxies have common age ranges from log(tyr) = 6.9 to log(tyr) = 7.3, and this indicates that these galaxies have experienced recent star formation within 20 Myr. Spatial correlation of RSGs with H II regions and their colour distribution were also investigated. For NGC 4449 and NGC 5457, the RSGs are spatially correlated with the H II regions, which however is not the case for NGC 5055. We found a similar colour distribution and a constant peak magnitude of MK = −11.9 for the RSGs in the three galaxies.
Effect of a Dipole Magnetic Field on Stellar Mass-Loss
Authors: Bard Chris , Townsend Richard
Published: July 2017

Massive star winds greatly influence the evolution of both their host star and local environment though their mass-loss rates, but current radiative line-driven wind models do not incorporate any magnetic effects. Recent surveys of O and B stars have found that about ten percent have large-scale, organized magnetic fields. These massive-star magnetic fields, which are thousands of times stronger than the Sun’s, affect the inherent properties of their own winds by changing the mass-loss rate. To quantify this, we present a simple surface mass-flux scaling over the stellar surface which can be easily integrated to get an estimate of the mass-loss rate for a magnetic massive star. The overall mass-loss rate is found to decrease by factors of 2-5 relative to the non-magnetic CAK mass-loss rate.
Hα imaging for BeXRBs in the Small Magellanic Cloud
Authors: Maravelias G. , Zezas A. , Antoniou V. , Hatzidimitriou D. , Haberl F.
Published: July 2017

The Small Magellanic Cloud (SMC) hosts a large number of high-mass X-ray binaries, and in particular of Be/X-ray Binaries (BeXRBs; neutron stars orbiting OBe-type stars), offering a unique laboratory to address the effect of metalicity. One key property of their optical companion is Hα in emission, which makes them bright sources when observed through a narrow-band Hα filter. We performed a survey of the SMC Bar and Wing regions using wide-field cameras (WFI@MPG/ESO and MOSAIC@CTIO/Blanco) in order to identify the counterparts of the sources detected in our XMM-Newton survey of the same area. We obtained broad-band R and narrow-band Hα photometry, and identified ~10000 Hα emission sources down to a sensitivity limit of 18.7 mag (equivalent to ~B8 type Main Sequence stars). We find the fraction of OBe/OB stars to be 13% down to this limit, and by investigating this fraction as a function of the brightness of the stars we deduce that Hα excess peaks at the O9-B2 spectral range. Using the most up-to-date numbers of SMC BeXRBs we find their fraction over their parent population to be ~0.002 − 0.025 BeXRBs/OBe, a direct measurement of their formation rate.
MASGOMAS project: building a bona-fide catalog of massive star cluster candidates
Authors: Herrero Artemio , Rübke Klaus , Alegría Sebastián Ramírez , Garcia Miriam , Marín-Franch Antonio
Published: July 2017

MASGOMAS (MAssive Stars in Galactic Obscured MAssive clusterS) is a project aiming at discovering OB stars in Galactic, dust enshrouded, star-forming massive clusters (Marín-Franch et al. 2009, A&A 502, 559). The project has gone through different phases of increasing automatization, that have allowed us to discover massive clusters like MASGOMAS-1 (Ramírez Alegría et al. 2012, A&A 541, A75) (with M≈20,000 M⊙).
The metallicity dependence of WR winds
Authors: Hainich R. , Shenar T. , Sander A. , Hamann W.-R. , Todt H.
Published: July 2017

Wolf-Rayet (WR) stars are the most advanced stage in the evolution of the most massive stars. The strong feedback provided by these objects and their subsequent supernova (SN) explosions are decisive for a variety of astrophysical topics such as the cosmic matter cycle. Consequently, understanding the properties of WR stars and their evolution is indispensable. A crucial but still not well known quantity determining the evolution of WR stars is their mass-loss rate. Since the mass loss is predicted to increase with metallicity, the feedback provided by these objects and their spectral appearance are expected to be a function of the metal content of their host galaxy. This has severe implications for the role of massive stars in general and the exploration of low metallicity environments in particular. Hitherto, the metallicity dependence of WR star winds was not well studied. In this contribution, we review the results from our comprehensive spectral analyses of WR stars in environments of different metallicities, ranging from slightly super-solar to SMC-like metallicities. Based on these studies, we derived empirical relations for the dependence of the WN mass-loss rates on the metallicity and iron abundance, respectively.
Properties of O dwarf stars in 30 Doradus
Authors: Sabín-Sanjulián Carolina ,   the VFTS collaboration
Published: July 2017

We perform a quantitative spectroscopic analysis of 105 presumably single O dwarf stars in 30 Doradus, located within the Large Magellanic Cloud. We use mid-to-high resolution multi-epoch optical spectroscopic data obtained within the VLT-FLAMES Tarantula Survey. Stellar and wind parameters are derived by means of the automatic tool iacob-gbat, which is based on a large grid of fastwind models. We also benefit from the Bayesian tool bonnsai to estimate evolutionary masses. We provide a spectral calibration for the effective temperature of O dwarf stars in the LMC, deal with the mass discrepancy problem and investigate the wind properties of the sample.
Symposium Summary
Authors: Levesque Emily M.
Published: July 2017

This proceeding summarizes the highlights of IAU 329, “The Lives and Death-Throes of Massive Stars”, held in Auckland, NZ from 28 Nov - 2 Dec. I consider the progress that has been made in the field over the course of these “beach symposia”, outline the overall content of the conference, and discuss how the current subfields in massive stellar astrophysics have evolved in recent years. I summarize some of the new results and innovative approaches that were presented during the symposium, and conclude with a discussion of how current and future resources in astronomy can serve as valuable tools for studying massive stars in the coming years.
The progenitors of core-collapse supernovae
Authors: Fraser Morgan
Published: July 2017

Linking core-collapse SNe to their stellar progenitors is a major ongoing challenge. To date, H rich Type IIP SNe have been shown to come from red supergiants, while there is increasing evidence that the majority of stripped envelope SNe come from binary systems. The first candidates for failed SNe, where a massive star collapses to form a black hole without a bright optical display have been identified, while the range of outbursts and eruptions from pre-SN stars are just beginning to be revealed.
What can distant galaxies teach us about massive stars?
Authors: Stanway Elizabeth R.
Published: July 2017

Observations of star-forming galaxies in the distant Universe (z > 2) are starting to confirm the importance of massive stars in shaping galaxy emission and evolution. Inevitably, these distant stellar populations are unresolved, and the limited data available must be interpreted in the context of stellar population synthesis models. With the imminent launch of JWST and the prospect of spectral observations of galaxies within a gigayear of the Big Bang, the uncertainties in modelling of massive stars are becoming increasingly important to our interpretation of the high redshift Universe. In turn, these observations of distant stellar populations will provide ever stronger tests against which to gauge the success of, and flaws in, current massive star models.
Time Lapse Spectropolarimetry: Constraining the Nature and Progenitors of Interacting CCSNe
Authors: Huk Leah
Published: July 2017

SNe of Type IIn are among the brightest supernova explosions due to strong circumstellar interaction. Examining the geometric and optical properties of the circumstellar material (CSM) can help to identify the progenitors of individual IIn SNe. Polarimetry is the optimal method for constraining CSM characteristics, as polarimetric signals both depend upon and preserve geometric information from unresolved sources. I present the results of fitting an ensemble of simulated polarized Hα emission-line profiles of interacting SNe, created using a three-dimensional Monte Carlo radiative transfer code called SLIP, to the multi-epoch observed polarized spectra of the Type IIn SN 1997eg. Further study of this model ensemble will allow us to investigate relationships among SNe IIn based on viewing angle and consider how the category should be subdivided based on physical properties of the CSM and/or progenitor.
X-ray diagnostics of massive star winds
Authors: Oskinova L. M. , Ignace R. , Huenemoerder D. P.
Published: July 2017

Observations with powerful X-ray telescopes, such as XMM-Newton and Chandra, significantly advance our understanding of massive stars. Nearly all early-type stars are X-ray sources. Studies of their X-ray emission provide important diagnostics of stellar winds. High-resolution X-ray spectra of O-type stars are well explained when stellar wind clumping is taking into account, providing further support to a modern picture of stellar winds as non-stationary, inhomogeneous outflows. X-ray variability is detected from such winds, on time scales likely associated with stellar rotation. High-resolution X-ray spectroscopy indicates that the winds of late O-type stars are predominantly in a hot phase. Consequently, X-rays provide the best observational window to study these winds. X-ray spectroscopy of evolved, Wolf-Rayet type, stars allows to probe their powerful metal enhanced winds, while the mechanisms responsible for the X-ray emission of these stars are not yet understood.
Low-metallicity (sub-SMC) massive stars
Authors: Garcia Miriam , Herrero Artemio , Najarro Francisco , Camacho Inés , Lennon Daniel J. , Urbaneja Miguel A. , Castro Norberto
Published: July 2017

The double distance and metallicity frontier marked by the SMC has been finally broken with the aid of powerful multi-object spectrographs installed at 8-10m class telescopes. VLT, GTC and Keck have enabled studies of massive stars in dwarf irregular galaxies of the Local Group with poorer metal-content than the SMC. The community is working to test the predictions of evolutionary models in the low-metallicity regime, set the new standard for the metal-poor high-redshift Universe, and test the extrapolation of the physics of massive stars to environments of decreasing metallicity. In this paper, we review current knowledge on this topic.
Extragalactic Supergiants
Authors: Urbaneja Miguel A. , Kudritzki Rolf P.
Published: July 2017

Blue supergiant stars of B and A spectral types are amongst the visually brightest non-transient astronomical objects. Their intrinsic brightness makes it possible to obtain high quality optical spectra of these objects in distant galaxies, enabling the study not only of these stars in different environments, but also to use them as tools to probe their host galaxies. Quantitative analysis of their optical spectra provide tight constraints on their evolution in a wide range of metallicities, as well as on the present-day chemical composition, extinction laws and distances to their host galaxies. We review in this contribution recent results in this field.
Tidal tearing of circumstellar disks in Be/X-ray and gamma-ray binaries
Authors: Okazaki Atsuo T.
Published: July 2017

About one half of high-mass X-ray binaries host a Be star [an OB star with a viscous decretion (slowly outflowing) disk]. These Be/X-ray binaries exhibit two types of X-ray outbursts (Stella et al. 1986), normal X-ray outbursts (LX~1036−37 erg s−1) and occasional giant X-ray outbursts (LX > 1037 erg s−1). The origin of giant X-ray outbursts is unknown. On the other hand, a half of gamma-ray binaries have a Be star as the optical counterpart. One of these systems [LS I +61 303 (Porb = 26.5 d)] shows the superorbital (1,667 d) modulation in radio through X-ray bands. No consensus has been obtained for its origin. In this paper, we study a possibility that both phenomena are caused by a long-term, cyclic evolution of a highly misaligned Be disk under the influence of a compact object, by performing 3D hydrodynamic simulations. We find that the Be disk cyclically evolves in mildly eccentric, short-period systems. Each cycle consists of the following stages:

1)

As the Be disk grows with time, the initially circular disk becomes eccentric by the Kozai-Lidov mechanism.

2)

At some point, the disk is tidally torn off near the base and starts precession.

3)

Due to precession, a gap opens between the disk base and mass ejection region, which allows the formation of a new disk in the stellar equatorial plane (see Figure 1).

4)

The newly formed disk finally replaces the precessing old disk. Such a cyclic disk evolution has interesting implications for the long-term behavior of high energy emission in Be/X-ray and gamma-ray binaries.
Evolution models of red supergiants
Authors: Georgy Cyril
Published: July 2017

The red supergiant (RSG) phase is a key stage for the evolution of massive stars. The current uncertainties about the mass-loss rates of these objects make their evolution far to be fully understood. In this paper, we discuss some of the physical processes that determine the duration of the RSG phase. We also show how the mass loss affect their evolution, and can allow for some RSGs to evolve towards the blue side of the Hertzsprung-Russell diagram. We also propose observational tests that can help in better understanding the evolution of these stars.
Photometric variability of the Be star population with the KELT survey
Authors: Labadie-Bartz Jonathan , Pepper Joshua , Chojnowski S. Drew , McSwain M. Virginia
Published: July 2017

We are using light curves from the KELT exoplanet transit survey (Pepper et al. 2007) to study the variability of hundreds of Be stars. Combining these light curves with simultaneous time-series spectra from the APOGEE survey (Majewski et al. 2015) provides a glimpse into how changes in the circumstellar environment are correlated to brightness variations.
Helium stars: Towards an understanding of Wolf–Rayet evolution
Authors: McClelland Liam A. S. , Eldridge J. J.
Published: July 2017

Recent observational modelling of the atmospheres of hydrogen-free Wolf–Rayet stars have indicated that their stellar surfaces are cooler than those predicted by the latest stellar evolution models. We have created a large grid of pure helium star models to investigate the dependence of the surface temperatures on factors such as the rate of mass loss and the amount of clumping in the outer convection zone. Upon comparing our results with Galactic and LMC WR observations, we find that the outer convection zones should be clumped and that the mass-loss rates need to be slightly reduced. We discuss the implications of these findings in terms of the detectability of Type Ibc supernovae progenitors, and in terms of refining the Conti scenario.
Conservative treatment of patients with thromboangiitis obliterans or cannabis-associated arteritis presenting with critical lower limb ischaemia
Authors: Galyfos George , Kerasidis Stavros , Kastrisios Georgios , Giannakakis Sotirios , Sachmpazidis Ioannis , Anastasiadou Christiana , Geropapas Georgios , Papapetrou Anastasios , Papacharalampous Gerasimos , Maltezos Chrisostomos
Published: July 2017

Abstract. Background: Proper management of patients with thromboangiitis obliterans (TAO) or cannabis-associated arteritis (CAA), presenting with critical lower limb ischaemia (CLI) remains controversial, and data are limited. Patients and methods: Patients with TAO or CAA presenting with CLI between 2011 and 2016 were retrospectively evaluated. Patients requiring primary intervention were excluded. Conservative treatment included: (a) weight-adjusted bemiparin plus six hours/day intravenous iloprost for 28 days, (b) aspirin (100 mg/day) plus cilostazol (100 mg twice/day) after discharge, and (c) strict recommendations/monitoring for smoking cessation. Main outcomes included symptom recession, ankle-brachial index (ABI) improvement, and healing of lesions at the time of discharge as well as amputation, revascularization, and abstinence rate during follow-up. Results: Overall, 23 patients (TAO: 15; CAA: 8) were included within six years, none of the patients reported any other factor than smoking. All patients presented with rest pain and 12 patients with ulcer or necrotic lesions. Mean ABI measurement at presentation was 0.46 ± 0.2, after 28 days of treatment, all patients showed improvement regarding clinical picture and ABI measurement (0.54 ± 0.1; p < 0.05). During follow-up, only three patients underwent bypass surgery and two patients underwent major amputation, although the smoking abstinence rate was very low (13 %). Conclusions: Intravenous iloprost plus bemiparin for 28 days together with per os aspirin plus cilostazol seem to produce promising results in patients with TAO/CAA, treated for CLI, even with a low smoking abstinence rate. However, larger series are needed to further evaluate inter-group differences and potential prognostic factors.
Primary School Students’ Implicit Theories and Their Reading	Motivation
Authors: Hellmich Frank , Hoya Fabian
Published: July 2017

Abstract. Parents’ and teachers’ effort feedback is considered to be an important prerequisite for children’s implicit theories of intelligence and their academic self-concepts as well as for their learning and achievement motivation. Therefore, our study examines whether differences in N = 685 primary school students’ implicit theories, their reading self-concepts, and their reading motivation can be predicted by their perceptions of their parents’ and teachers’ effort feedback on reading processes. The results of a structural equation model show that children’s perceptions of their parents’ effort feedback predict their implicit theories, their reading self-concepts, and their reading motivation. The correlation between children’s perceived parental effort feedback and their intrinsic reading motivation is mediated by their implicit theories. Children’s implicit theories and their reading motivation cannot be predicted by their perceptions of their teachers’ effort feedback.
Examining the Effects of Task Instructions to Induce Implicit	Theories of Intelligence on a Rational Thinking Task
Authors: Bråten Ivar , Lien Andreas , Nietfeld John
Published: July 2017

Abstract. In two experiments with Norwegian undergraduates and one experiment with US undergraduates, we examined the potential effects of brief task instructions aligned with incremental and entity views of intelligence on students’ performance on a rational thinking task. The research demonstrated that even brief one-shot task instructions that deliver a mindset about intelligence intervention can be powerful enough to affect students’ performance on such a task. This was only true for Norwegian male students, however. Moreover, it was the task instruction aligned with an entity theory of intelligence that positively affected Norwegian male students’ performance on the rational thinking task, with this unanticipated finding speaking to the context- and culture-specificity of implicit theories of intelligence interventions.
Correction: Corrigendum: Large-scale production of megakaryocytes from human pluripotent stem cells by chemically defined forward programming
Authors: Moreau Thomas , Evans Amanda L. , Vasquez Louella , Tijssen Marloes R. , Yan Ying , Trotter Matthew W. , Howard Daniel , Colzani Maria , Arumugam Meera , Wu Wing Han , Dalby Amanda , Lampela Riina , Bouet Guenaelle , Hobbs Catherine M. , Pask Dean C. , Payne Holly , Ponomaryov Tatyana , Brill Alexander , Soranzo Nicole , Ouwehand Willem H. , Pedersen Roger A. , Ghevaert Cedric
Published: July 2017

Nature Communications 7 Article number: 11208 (2016) Published 7 April 2016; Updated 28 July 2017 This Article contains an error in the author contributions section that has resulted in incorrect credit for preparation and critical analysis of the manuscript. The correct author contributions sectionis as follows:
53-attosecond X-ray pulses reach the carbon K-edge
Authors: Li Jie , Ren Xiaoming , Yin Yanchun , Zhao Kun , Chew Andrew , Cheng Yan , Cunningham Eric , Wang Yang , Hu Shuyuan , Wu Yi , Chini Michael , Chang Zenghu
Published: July 2017

The motion of electrons in the microcosm occurs on a time scale set by the atomic unit of time—24 attoseconds. Attosecond pulses at photon energies corresponding to the fundamental absorption edges of matter, which lie in the soft X-ray regime above 200 eV, permit the probing of electronic excitation, chemical state, and atomic structure. Here we demonstrate a soft X-ray pulse duration of 53 as and single pulse streaking reaching the carbon K-absorption edge (284 eV) by utilizing intense two-cycle driving pulses near 1.8-μm center wavelength. Such pulses permit studies of electron dynamics in live biological samples and next-generation electronic materials such as diamond.
Predictive modeling of Time-Temperature-Transformation diagram of metallic glasses based on atomistically-informed classical nucleation theory
Authors: Sato Yuji , Nakai Chiaki , Wakeda Masato , Ogata Shigenobu
Published: July 2017

Theoretical prediction of glass forming ability (GFA) of metallic alloys is a key process in exploring metallic alloy compositions with excellent GFA and thus with the ability to form a large-sized bulk metallic glass. Molecular dynamics (MD) simulation is a promising tool to achieve a theoretical prediction. However, direct MD prediction continues to be challenging due to the time-scale limitation of MD. With respect to practical bulk metallic glass alloys, the time necessary for quenching at a typical cooling rate is five or more orders of magnitude higher than that at the MD time-scale. To overcome the time-scale issue, this study proposes a combined method of classical nucleation theory and MD simulations. The method actually allows to depict the time-temperature-transformation (TTT) diagram of the bulk metallic glass alloys. The TTT directly provides a prediction of the critical cooling rate and GFA. Although the method assumes conventional classical nucleation theory, all the material parameters appearing in the theory were determined by MD simulations using realistic interatomic potentials. The method is used to compute the TTT diagrams and critical cooling rates of two Cu-Zr alloy compositions (Cu50Zr50 and Cu20Zr80). The results indicate that the proposed method reasonably predicts the critical cooling rate based on the computed TTT.
Uracil Accumulation and Mutagenesis Dominated by Cytosine Deamination in CpG Dinucleotides in Mice Lacking UNG and SMUG1
Authors: Alsøe Lene , Sarno Antonio , Carracedo Sergio , Domanska Diana , Dingler Felix , Lirussi Lisa , SenGupta Tanima , Tekin Nuriye Basdag , Jobert Laure , Alexandrov Ludmil B. , Galashevskaya Anastasia , Rada Cristina , Sandve Geir Kjetil , Rognes Torbjørn , Krokan Hans E. , Nilsen Hilde
Published: July 2017

Both a DNA lesion and an intermediate for antibody maturation, uracil is primarily processed by base excision repair (BER), either initiated by uracil-DNA glycosylase (UNG) or by single-strand selective monofunctional uracil DNA glycosylase (SMUG1). The relativein vivocontributions of each glycosylase remain elusive. To assess the impact of SMUG1 deficiency, we measured uracil and 5-hydroxymethyluracil, another SMUG1 substrate, inSmug1−/−mice. We found that 5-hydroxymethyluracil accumulated inSmug1−/−tissues and correlated with 5-hydroxymethylcytosine levels. The highest increase was found in brain, which contained about 26-fold higher genomic 5-hydroxymethyluracil levels than the wild type.Smug1−/−mice did not accumulate uracil in their genome andUng−/−mice showed slightly elevated uracil levels. Contrastingly,Ung−/−Smug1−/−mice showed a synergistic increase in uracil levels with up to 25-fold higher uracil levels than wild type. Whole genome sequencing of UNG/SMUG1-deficient tumours revealed that combined UNG and SMUG1 deficiency leads to the accumulation of mutations, primarily C to T transitions within CpG sequences. This unexpected sequence bias suggests that CpG dinucleotides are intrinsically more mutation prone. In conclusion, we showed that SMUG1 efficiently prevent genomic uracil accumulation, even in the presence of UNG, and identified mutational signatures associated with combined UNG and SMUG1 deficiency.