bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-term treatment in chronic noncancer pain: Results of an observational study comparing opioid and nonopioid therapy
Authors: Elsesser Karin , Cegla Thomas
Published: August 2017

Background and aims

Recent studies reveal high prevalence rates of patients receiving long-term opioids. However, well designed studies assessing effectiveness with longer than 3 months follow-up are sparse. The present study investigated the outcomes of long-term opioid therapy compared to nonopioid treatment in CNCP patients with respect to measures of pain, functional disability, psychological wellbeing, and quality of life (QoL).

Methods

Three hundred and thirty three consecutive patients at our pain clinic were included and divided into patients with continuous opioid treatment for at least 3 months (51%) and patients receiving nonopioid analgesics (49%). Further, outcome of different doses of opioid (<120 mg vs. >120 mg morphine equivalents) and differences between high and low potency opioids were examined.

Results

The opioid and nonopioid groups did not differ with regard to pain intensity or satisfaction with analgesic. Patients with continuous opioids treatment reported higher neuropathic like pain, longer duration of pain disorder, lower functional level, wellbeing, and physical QoL in comparison to patients receiving nonopioid analgesics. Higher opioid doses were associated with male gender, intake of high potency opioids and depression but there were no differences with regard to pain relief or improvement of functional level between high and low doses. Similarly, patients on high potency opioids reported more psychological impairment than patients on low potency opioids but no advantage with regard to pain relief. Overall, remaining level of pain, functional disability and poor QoL were quite high irrespective of the analgesic used or opioid dosing.

Conclusions

In the long-term no clear advantage of opioid vs. non-opioid analgesics could be revealed. In terms of remaining pain intensity, functional disability and quality of life, treatment with pain medication proved insufficient. Additionally, with higher doses of opioids the benefit to risk relationship becomes worse and patients on high potency opioids reported more psychological impairment than patients on low potency opioids but no advantage with regard to pain relief.

Implications

Our results raise questions about the long-term effectiveness of analgesic treatment regimens irrespective of analgesics type employed and call for more multidisciplinary treatment strategies.
Socioeconomic status and anterior epistaxis in adult population
Authors: Masoudian Pourya , McDonald J. Ted , Lasso Andrea , Kilty Shaun J.
Published: August 2017

Objective

Little was known about the role of socioeconomic status as a risk factor for epistaxis in adult population. The objective of this study was to determine whether socioeconomic status influences the presentation to emergency department for anterior epistaxis in an adult population.

Methods

Retrospective review of emergency department visits from January 2012 to May 2014. The setting is in an emergency department of a Canadian tertiary care centre. Adult patients with primary diagnosis of anterior epistaxis in the emergency department were included in this study. The main outcome was emergency department visits for anterior epistaxis visits.

Results

A total of 351 cases of anterior epistaxis were included. The mean age was 70 years and 51% of patients were male. The patients were stratified into two groups based on whether their age was equal to and above, or below 75 years. Our analysis indicated that those 75 years or older in higher income quintiles have an increased risk of anterior epistaxis compared to the subjects in the lower income quintiles (P < 0.05). This association did not hold true for those younger than 75 years or for all age groups combined.

Conclusion

There is an association between higher socioeconomic status and the presentation to the emergency department with anterior epistaxis in the population older than 75 years but not in younger patients.
SINGLE-GRAIN OPTICALLY STIMULATED LUMINESCENCE AGES OF BROWNWARE POTTERY IN THE MIDDLE ROCKY MOUNTAINS AND THE SPREAD OF NUMIC CERAMIC TECHNOLOGY
Authors: Finley Judson Byrd , Ideker Carlie J. , Rittenour Tammy
Published: August 2017

This study presents the results of a single-grain optically stimulated luminescence (SG-OSL) analysis of brownware pottery from four Late Prehistoric-period sites in the Middle Rocky Mountains, Wyoming, USA. SG-OSL of quartz ceramic temper provides improved age control for sites where radiocarbon dating has proven problematic due to old wood, recent wildfires, and calibration uncertainties. SG-OSL results are compared to fine-grain infrared stimulated luminescence (FG-IRSL) results from the same sherds and associated radiocarbon ages. We find that the single-grain technique applied to quartz sand temper provides improved accuracy and precision over both FG-IRSL and radiocarbon. We compare our results to directly dated brownwares from the southern and eastern Great Basin based largely on thermoluminescence analysis. While brownware ceramics appear earliest in the southwestern Great Basin, our data show that the technology spread quickly to the northeastern margin of the Numic homelands. We suggest that knowledge of ceramic technology in Formative (i.e., Ancestral Pueblo and Fremont) societies was important in the adoption of pottery by Numic hunter-gatherers and that, like in the southwestern Great Basin, this technological adaptation in the Middle Rocky Mountains may have occurred within a context of resource intensification during the last 800 years.
Exact coherent structures in stably stratified plane Couette flow
Authors: Olvera D. , Kerswell R. R.
Published: August 2017

The existence of exact coherent structures in stably stratified plane Couette flow (gravity perpendicular to the plates) is investigated over Reynolds–Richardson number ($Re$–$Ri_{b}$) space for a fluid of unit Prandtl number $(Pr=1)$ using a combination of numerical and asymptotic techniques. Two states are repeatedly discovered using edge tracking – EQ7 and EQ7-1 in the nomenclature of Gibson & Brand (J. Fluid Mech., vol. 745, 2014, pp. 25–61) – and found to connect with two-dimensional convective roll solutions when tracked to negative $Ri_{b}$ (the Rayleigh–Bénard problem with shear). Both these states and Nagata’s (J. Fluid Mech., vol. 217, 1990, pp. 519–527) original exact solution feel the presence of stable stratification when $Ri_{b}=O(Re^{-2})$ or equivalently when the Rayleigh number $Ra:=-Ri_{b}Re^{2}Pr=O(1)$. This is confirmed via a stratified extension of the vortex wave interaction theory of Hall & Sherwin (J. Fluid Mech., vol. 661, 2010, pp. 178–205). If the stratification is increased further, EQ7 is found to progressively spanwise and cross-stream localise until a second regime is entered at $Ri_{b}=O(Re^{-2/3})$. This corresponds to a stratified version of the boundary region equations regime of Deguchi, Hall & Walton (J. Fluid Mech., vol. 721, 2013, pp. 58–85). Increasing the stratification further appears to lead to a third, ultimate regime where $Ri_{b}=O(1)$ in which the flow fully localises in all three directions at the minimal Kolmogorov scale which then corresponds to the Osmidov scale. Implications for the laminar–turbulent boundary in the ($Re$–$Ri_{b}$) plane are briefly discussed.
Rodent eradication scaled up: clearing rats and mice from South Georgia
Authors: Martin A. R. , Richardson M. G.
Published: August 2017

The Subantarctic island of South Georgia lost most of its birds to predation by rodents introduced by people over 2 centuries. In 2011 a UK charity began to clear brown ratsRattus norvegicusand house miceMus musculusfrom the 170 km long, 3,500 km2island using helicopters to spread bait containing Brodifacoum as the active ingredient. South Georgia's larger glaciers were barriers to rodent movement, resulting in numerous independent sub-island populations. The eradication could therefore be spread over multiple seasons, giving time to evaluate results before recommencing, and also reducing the impact of non-target mortality across the island as a whole. Eradication success was achieved in the 128 km2Phase 1 trial operation. Work in 2013 (Phase 2) and early 2015 (Phase 3) covered the remaining 940 km2occupied by rodents. By July 2017, 28 months after baiting was concluded, there was no sign of surviving rodents, other than one apparently newly introduced by ship in October 2014. A survey using detection dogs and passive devices will search the Phase 2 and Phase 3 land for rodents in early 2018. Seven (of 30) species of breeding birds suffered losses from poisoning, but all populations appear to have recovered within 5 years. The endemic South Georgia pipitAnthus antarcticuswas the first bird to breed in newly rat-free areas, but there were also signs that cavity-nesting seabirds were exploring scree habitat denied them for generations. Enhanced biosecurity measures on South Georgia are needed urgently to prevent rodents being reintroduced.
CanWolbachiamodulate the fecundity costs ofPlasmodiumin mosquitoes?
Authors: Zélé F , Denoyelle J , Duron O , Rivero A
Published: August 2017

Vertically transmitted parasites (VTPs) such asWolbachiaare expected not only to minimize the damage they inflict on their hosts, but also to protect their hosts against the damaging effects of coinfecting parasites. By modifying the fitness costs of the infection, VTPs can therefore play an important role in the evolution and epidemiology of infectious diseases.

Using a natural system, we explore the effects of aWolbachia–Plasmodiumco-infection on mosquito fecundity. WhilePlasmodiumis known to frequently express its virulence by partially castrating its mosquito vectors, the effects ofWolbachiainfections on mosquito fecundity are, in contrast, highly variable. Here, we show thatPlasmodiumdrastically decreases the fecundity of mosquitoes by ca. 20%, and we provide the first evidence that this decrease is independent of the parasite's burden.Wolbachia, on the other hand, increases fecundity by roughly 10%, but does not alter the tolerance (fecundity–burden relationship) of mosquitoes toPlasmodiuminfection.

AlthoughWolbachia-infected mosquitoes fare overall better than uninfected ones,Wolbachiadoes not confer a sufficiently high reproductive boost to mosquitoes to compensate for the reproductive losses inflicted byPlasmodium.We discuss the potential mechanisms and implications underlying the conflicting effects of these two parasites on mosquito reproduction.
Of pagan festivals and meta-narratives: Recovering the awareness of our shared humanness
Authors: Mouw Richard J.
Published: August 2017

The notion of human commonness was a key interest of the nineteenth-century theologian-statesman Abraham Kuyper. As an orthodox Calvinist, Kuyper accepted the division of humankind into the categories of ‘elect’ and ‘non-elect’, but he was also convinced that this way of classifying human beings failed to account for the positive contributions of non-Christians. As a political leader, Kuyper was also concerned to enlist his fellow Calvinists in the quest for justice in the larger society and specifically focused on the ways in which Christian worship can nurture a sense of shared humanness that extends beyond the walls of the church. In our contemporary setting, where our loss of an emphasis on a shared humanness is becoming widespread, Kuyper's effort to ground human solidarity in the practices of worship has much to commend it.
The eclipse of Daniel's narrative: The limits of historical knowledge in the theological reading of Daniel
Authors: Briggs Richard S.
Published: August 2017

This article uses Hans Frei's famous image of the ‘eclipse’ of biblical narrative to explore the link between situating the book of Daniel historically and grasping its theological point(s). The critical/conservative stand-off over the book of Daniel is rehearsed by way of key agenda-setting Victorian voices, and it is then argued that Frei's perspective allows the reader to move on from assessing descriptive accuracy towards focusing on ascriptive purpose(s). Various examples of how such an ascriptive approach might clarify Daniel are considered, including specific attention to the complexities of Daniel 11’s problematic relationship to what did and did not happen to Antiochus Epiphanes.
Quakerism understood in relation to Calvinism: The theology of George Fox
Authors: Rock Hugh
Published: August 2017

This article starts from the position that Quakerism has yet to be properly located within the firmament of Christian theology. A new starting point is proposed in the relation to the historical environment of Calvinism, the effect of which is to place Quakerism within the ancient stand-off between Augustine and Pelagius. In the article's first part, four theological propositions taken from the Journal of George Fox are first contrasted with propositions from John Calvin's Institutes of the Christian Religion and then correlated with those of James Arminius to confirm the Pelagian nature of the theology. The second part of the article departs from particular doctrinal elements and attempts to grasp the contrasting characters of Quakerism and Calvinism.
Anagram-Free Colourings of Graphs
Authors: KAMČEV NINA , ŁUCZAK TOMASZ , SUDAKOV BENNY
Published: August 2017

A sequenceSis calledanagram-freeif it contains no consecutive symbolsr1r2. . .rkrk+1. . .r2ksuch thatrk+1. . .r2kis a permutation of the blockr1r2. . .rk. Answering a question of Erdős and Brown, Keränen constructed an infinite anagram-free sequence on four symbols. Motivated by the work of Alon, Grytczuk, Hałuszczak and Riordan [2], we consider a natural generalization of anagram-free sequences for graph colourings. A colouring of the vertices of a given graphGis calledanagram-freeif the sequence of colours on any path inGis anagram-free. We call the minimal number of colours needed for such a colouring theanagram-chromaticnumber ofG.

In this paper we study the anagram-chromatic number of several classes of graphs like trees, minor-free graphs and bounded-degree graphs. Surprisingly, we show that there are bounded-degree graphs (such as random regular graphs) in which anagrams cannot be avoided unless we essentially give each vertex a separate colour.
Association between oral sildenafil dosing, predicted exposure, and systemic hypotension in hospitalised infants
Authors: Hornik Christoph P. , Onufrak Nikolas J. , Smith P. Brian , Cohen-Wolkowiez Michael , Laughon Matthew M. , Clark Reese H. , Gonzalez Daniel
Published: August 2017

Background

The relationship between sildenafil dosing, exposure, and systemic hypotension in infants is incompletely understood.

Objectives

The aim of this study was to characterise the relationship between predicted sildenafil exposure and hypotension in hospitalised infants.

Methods

We extracted information on sildenafil dosing and clinical characteristics from electronic health records of 348 neonatal ICUs from 1997 to 2013, and we predicted drug exposure using a population pharmacokinetic model.

Results

We identified 232 infants receiving sildenafil at a median dose of 3.2 mg/kg/day (2.0, 6.0). The median steady-state area under the concentration–time curve over 24 hours (AUC24,SS) and maximum concentration of sildenafil (Cmax,SS,SIL) were 712 ng×hour/ml (401, 1561) and 129 ng/ml (69, 293), respectively. Systemic hypotension occurred in 9% of the cohort. In multivariable analysis, neither dosing nor exposure were associated with systemic hypotension: odds ratio=0.96 (95% confidence interval: 0.81, 1.14) for sildenafil dose; 0.87 (0.59, 1.28) for AUC24,SS; 1.19 (0.78, 1.82) for Cmax,SS,SIL.

Conclusions

We found no association between sildenafil dosing or exposure with systemic hypotension. Continued assessment of sildenafil’s safety profile in infants is warranted.
Community Health Workers and Disasters: Lessons Learned from the 2015 Earthquake in Nepal
Authors: Fredricks Karla , Dinh Hao , Kusi Manita , Yogal Chandra , Karmacharya Biraj M. , Burke Thomas F. , Nelson Brett D.
Published: August 2017

Introduction

The Nepal earthquake of 2015 was a major disaster that exacted an enormous toll on human lives and caused extensive damage to the infrastructure of the region. Similar to other developing countries, Nepal has a network of community health workers (CHWs; known as female community health volunteers [FCHVs]) that was in place prior to the earthquake and continues to function to improve maternal and child health. These FCHVs and other community members were responsible, by default, for providing the first wave of assistance after the earthquake.

Hypothesis/Problem

Community health workers such as FCHVs could be used to provide formal relief services in the event of an emergency, but there is a paucity of evidence-based literature on how to best utilize them in disaster risk reduction, preparedness, and response. Data are needed to further characterize the roles that this cadre has played in past disasters and what strategies can be implemented to better incorporate them into future emergency management.

Methods

In March 2016, key-informant interviews, FCHV interviews, and focus group discussions (FGDs) were conducted in Nepali health facilities using semi-structured guides. The audio-recorded data were obtained with the assistance of a translator (Nepali-English), transcribed verbatim in English, and coded by two independent researchers (manually and with NVivo 11 Pro software [QSR International; Melbourne, Australia]).

Results

Across seven different regions, 14 interviews with FCHVs, two FGDs with community women, and three key-informant interviews were conducted. Four major themes emerged around the topic of FCHVs and the 2015 earthquake: (1) community care and rapport between FCHVs and local residents; (2) emergency response of FCHVs in the immediate aftermath of the earthquake; (3) training requested to improve the FCHVs’ ability to manage disasters; and (4) interaction with relief organizations and how to create collaborations that provide aid relief more effectively.

Conclusions

The FCHVs in Nepal provided multiple services to their communities in the aftermath of the earthquake, largely without any specific training or instruction. Proper preparation, in addition to improved collaboration with aid agencies, could increase the capacity of FCHVs to respond in the event of a future disaster. The information gained from this study of the FCHV experience in the Nepal earthquake could be used to inform risk reduction and emergency management policies for CHWs in various settings worldwide.

FredricksK, DinhH, KusiM, YogalC, KarmacharyaBM, BurkeTF, NelsonBD. Community health workers and disasters: lessons learned from the 2015 earthquake in Nepal. Prehosp Disaster Med. 2017;32(6):604–609.
Practical Aspects of Electrochemical Corrosion Measurements During In Situ Analytical Transmission Electron Microscopy (TEM) of Austenitic Stainless Steel in Aqueous Media
Authors: Schilling Sibylle , Janssen Arne , Zaluzec Nestor J. , Burke M. Grace
Published: August 2017

The capability to perform liquid in situ transmission electron microscopy (TEM) experiments provides an unprecedented opportunity to examine the real-time processes of physical and chemical/electrochemical reactions during the interaction between metal surfaces and liquid environments. This work describes the requisite steps to make the technique fully analytical, from sample preparation, through modifications of the electrodes, characterization of electrolytes, and finally to electrochemical corrosion experiments comparing in situ TEM to conventional bulk cell and microcell configurations.
Information and communication technologies in primary healthcare facilities in Egypt
Authors: Farahat Taghreed M. , Hegazy Nagwa N. , Mowafy Maha
Published: August 2017

Background

The health sector has always relied on technologies. According to World Health Organization, they form the backbone of the services to prevent, diagnose, and treat illness and disease. It is increasingly viewed as the most promising tool for improving the overall quality, safety and efficiency of the health delivery system.

Aim of the study

This was to assess the current situation of information and communication technologies (ICTs) in primary healthcare in the terms of describing and classifying the existing work, identify gaps and exploring the personal experiences and the challenges of ICTs application in the primary healthcare.

Subjects and methods

A mixed research method in the form of sequential explanatory design was applied. In the quantitative phase a cross-sectional study was conducted among 172 family physicians using a predesigned questionnaire. Followed by qualitative data collection among 35 participants through focused group discussions.

Results

Nearly half of the physicians have ICTs in their work and they were trained on it. None of them developed a community-based research using ICTs technology. Training on ICTs showed a statistically significant difference regarding the availability and the type of ICTs present in the workplace (P<0.05). Focused group discussion revealed that the majority of the participants believe that there is poor commitment of policymaker toward ICTs utilization in the primary care. Nearly 97% thinks that there is insufficient budget allocated for ICTs utilization in the workplace. Almost 88% of the participants demanded more incentives for ICTs users than non-user at the workplace.

Conclusions

ICTs resources are underutilized by health information professionals. Lack of funds, risk of instability of the electric supply and lack of incentives for ICTs users were the most common barriers to ICTs implementation thus a steady steps toward budget allocation and continuous training is needed.
The Planetary Nebulae Luminosity Function (PNLF): current perspectives
Authors: Méndez Roberto H.
Published: August 2017

This paper starts with a brief historical review about the PNLF and its use as a distance indicator. Then the PNLF distances are compared with Surface Brightness Fluctuations (SBF) distances and Tip of the Red Giant Branch (TRGB) distances. A Monte Carlo method to generate simulated PNLFs is described, leading to the last subject: recent progress in reproducing the expected maximum final mass in old stellar populations, a stellar astrophysics enigma that has been challenging us for quite some time.
Planetary Nebula Candidates Uncovered with the HASH Research Platform
Authors: Fragkou Vasiliki , Bojičić Ivan , Frew David , Parker Quentin
Published: August 2017

A detailed examination of new high quality radio catalogues (e.g. Cornish) in combination with available mid-infrared (MIR) satellite imagery (e.g. Glimpse) has allowed us to find 70 new planetary nebula (PN) candidates based on existing knowledge of their typical colors and fluxes. To further examine the nature of these sources, multiple diagnostic tools have been applied to these candidates based on published data and on available imagery in the HASH (Hong Kong/ AAO/ Strasbourg Hα planetary nebula) research platform. Some candidates have previously-missed optical counterparts allowing for spectroscopic follow-up. Indeed, the single object spectroscopically observed so far has turned out to be a bona fide PN.
The Binary Central Star of Hf 38
Authors: Barker Helen
Published: August 2017

Despite years of effort, the impact of central star binarity on planetary nebula formation and shaping remains unclear. This is hampered by the fact that detecting central star binarity is inherently difficult, and requires very precise observations. The fraction of planetary nebulae with binary central stars therefore remains elusive. This work presents initial results of central star analysis using data from the VST Hα Survey of the Southern Galactic Plane and Bulge (VPHAS+). The true central star of PN Hf 38 has been revealed, and it exhibits a 0.465±0.334 i band magnitude excess, indicative of a M0V companion.
Planet destruction and the shaping of planetary nebulae
Authors: Boyle L. A. , Redman M. P.
Published: August 2017

The shaping of PNe as a result of an interaction with a planet is a hypothesis that has been suggested for nearly two decades. However, exploring the idea observationally is challenging due to the lack of capabilities needed to detect any evidence of such a scenario. Nonetheless, we propose that the hypothesis can be indirectly tested via a combination of exoplanet formation and evolution theories, the star and planet formation histories of the galaxy and the tidal evolution of star-planet systems. We present a calculation of the fraction of planetary nebulae in the galaxy today which have undergone an interaction with a planet, concluding that a significant number of visible planetary nebulae may have been shaped by a planet.
Kinematic and chemical analysis of PNe in NGC 3109
Authors: Flores-Dúran Sheila N. , Peña Miriam , Ruiz María T.
Published: August 2017

We present high resolution spectroscopy obtained with MIKE-Magellan and MES OAN-SPM of a number of planetary nebulae (PNe) and H ii regions, distributed along the dwarf irregular galaxy NGC 3109 and compare their kinematical behavior with the one of H i data. We aim to determine if there is a kinematical connection among these objects. We also perform a revision of the chemical composition of PNe and H ii regions in this galaxy and discuss it in comparison with stellar evolution models.
The very fast evolution of Sakurai's object
Authors: Van de Steene G. C. , van Hoof P. A. M. , Kimeswenger S. , Zijlstra A. A. , Avison A. , Guzman-Ramirez L. , Hajduk M. , Herwig F.
Published: August 2017

V4334 Sgr (a.k.a. Sakurai's object) is the central star of an old planetary nebula that underwent a very late thermal pulse a few years before its discovery in 1996. We have been monitoring the evolution of the optical emission line spectrum since 2001. The goal is to improve the evolutionary models by constraining them with the temporal evolution of the central star temperature. In addition the high resolution spectral observations obtained by X-shooter and ALMA show the temporal evolution of the different morphological components.
A homogeneous distance catalogue for Galactic RV Tauri objects
Authors: Vickers Shane B. , Frew David J. , Owers Matt S. , Parker Quentin A. , Bojičić Ivan S.
Published: August 2017

A subset of Post-AGB (PAGB) objects are the highly luminous RV Tauri variables that show similarities to Type-II Cepheids. By using a sample of known RV Tauri stars from the Magellanic Clouds we are able to determine period luminosity relationships (PLRs) in various bands that have been used to determine the luminosities of their Galactic counterparts. We have gathered all available photometry in order to generate an SED for each object and determine the total integrated flux. This total flux combined with a calculated or inferred intrinsic luminosity leads to a distance (Vickers et al. 2015). This distance catalogue has allowed us to begin to constrain the physical parameters of this poorly understood evolutionary phase and to determine links between these physical characteristics as a function of their stellar population.
What can VLBI astrometry tell us about AR Sco?
Authors: Cui Lang , Yang Jun , Ma Hongli , Liu Jun , Chen Wen
Published: August 2017

We proposed to carry out high precision very long baseline interferometry (VLBI) observations of AR Sco, a pulsing white dwarf (WD) - M dwarf (MD) binary, to provide a direct distance measurement with the e-EVN (European VLBI Network) at 5 GHz. By the proposed parallax measurement on AR Sco, not only the precise distance will be determined, but also some physical parameters, such as the luminosity, the mass and the magnetic field will be significantly tightened accordingly, even the gravitational wave amplitude from this unique binary system can be tightly constrained. In addition, the EVN observations will allow us to answer that whether there is an extended emission structure associated with AR Sco, which will help us to explain the stable continuum radio emission observed during the pulse-off state.
Atomic Data and Neutron-Capture Element Abundances in Planetary Nebulae
Authors: Sterling N. C.
Published: August 2017

Neutron(n)-capture elements are produced by s-process nucleosynthesis in low- and intermediate-mass AGB stars, and therefore can be enriched in planetary nebulae (PNe). In the last ten years, n-capture elements have been detected in more than 100 PNe in the Milky Way and nearby galaxies. In some objects, several different n-capture elements have been detected, providing valuable constraints to models of AGB nucleosynthesis and evolution. These detections have motivated theoretical and experimental investigations of the atomic data needed to derive accurate n-capture element abundances. In this review, I discuss the methods and results of these atomic data studies, and their application to abundance determinations in PNe.
Abundances of Iron-Group Elements in Planetary Nebulae and Consequences for Chemical Enrichment
Authors: Dinerstein Harriet L. , Geballe T. R. , Sterling N. C.
Published: August 2017

We have developed a method for determining elemental Fe-group abundances in planetary nebulae using an infrared emission line of Zn, the least refractory Fe-group species. Many planetary nebulae, particularly those of the Milky Way’s thick disk and bulge, display subsolar [Fe/H] (as inferred from Zn) although their abundances of α elements such as O, S, and Ar are nearly solar. We discuss the implications for determining enhancements of species synthesized by the progenitor star during the AGB (e.g.,s-process products), and for galactic chemical evolution in view of the metallicity dependence of AGB nucleosynthetic yields.
Binary interactions on the RGB: Dusty post-RGB stars
Authors: Kamath Devika , Van Winckel Hans , Wood Peter
Published: August 2017

It is widely accepted that binary interactions are responsible for the shaping of planetary nebula. However, these binary interactions and evolutionary channels are poorly understood. Our recent study revealed a newly discovered population of low-luminosity, low-metallicity, likely binaries in the Magellanic Clouds: dusty post-RGB stars. They are likely to have evolved off the RGB via binary interaction. In this paper we present preliminary results of the first radial velocity monitoring of the post-RGB stars in the Small Magellanic Cloud (SMC) and the implications on stellar (binary) evolution. We also investigate their link, if any, to the planetary nebulae systems.
Dust & Abundances of Metal-Poor Planetary Nebulae in the Galactic Anti-Center
Authors: Pagomenos George J. S. , Bernard-Salas Jeronimo , Sloan G. C.
Published: August 2017

Much of the new dust in the local ISM is produced in the last phases of stellar evolution of low- and intermediate-mass stars on the Asymptotic Giant Branch (AGB). Despite its importance, our knowledge of how dust properties depend on metallicity is limited. Studies of planetary nebulae in irregular galaxies in the Local Group (mostly focused on the LMC and SMC) have revealed a diverse spectral zoo and shown that low metallicity favours carbon-rich dust production by AGB stars. However, at ~1/3 and ~1/5 times the solar metallicity respectively, they provide two snapshots of dust composition at low metallicity, emphasising the need to investigate a region with a range of metallicity values. With its abundance gradient, the Milky Way fits this criterion and provides a good opportunity to observe the dust composition over a large metallicity range. In particular the Galactic anti-center, which is largely unexplored beyond galactocentric distances of 10 kpc, allows us to study the AGB dust a priori assumed to be metal-poor as well as exploring the extent of the Galactic abundance gradient. We analyse a Spitzer spectroscopic sample of 23 planetary nebulae towards the anti-center in order to understand how the metallicity gradient extends beyond 10 kpc from the Galactic center and to observe the dust composition in this region of our Galaxy. We find that the abundance gradients of Ne, S and Ar continue to distances of around 20 kpc (albeit with a large scatter) and the dust emission shows a carbon-rich chemistry similar to that in the Magellanic Clouds.
Conference Summary
Authors: Kwok Sun
Published: August 2017

The progress in planetary nebulae (PN) research reported in this symposium is reviewed in the context of our current understanding of the PN phenomenon.
Hunting for binary central stars of planetary nebulae: exploiting archival data
Authors: Aller Alba , Vučković Maja , Lillo-Box Jorge , Miranda Luis F. , Jones David , Boffin Henri M. J.
Published: August 2017

The detection of new binary central stars of planetary nebulae is crucial to definitively determine the importance of binary interactions in the nebular morphology. In this context, we are working on a project that aims to increase the low number of binary central stars detected so far. For that, we are first analyzing public archival data in order to discover potential candidates of binary central stars. These candidates will be subsequently followed-up in order to confirm and characterize them. Here we present our ongoing search and some preliminary results.
Imaging the elusive H-poor gas in planetary nebulae with large abundance discrepancy factors
Authors: García-Rojas Jorge , Corradi Romano L. M. , Boffin Henri M. J. , Monteiro Hektor , Jones David , Wesson Roger , Cabrera-Lavers Antonio , Rodríguez-Gil Pablo
Published: August 2017

The discrepancy between abundances computed using optical recombination lines (ORLs) and collisionally excited lines (CELs) is a major, unresolved problem with significant implications for the determination of chemical abundances throughout the Universe. In planetary nebulae (PNe), the most common explanation for the discrepancy is that two different gas phases coexist: a hot component with standard metallicity, and a much colder plasma enhanced in heavy elements. This dual nature is not predicted by mass loss theories, and direct observational support for it is still weak. In this work, we present our recent findings that demonstrate that the largest abundance discrepancies are associated with close binary central stars. OSIRIS-GTC tunable filter imaging of the faint O ii ORLs and MUSE-VLT deep 2D spectrophotometry confirm that O ii ORL emission is more centrally concentrated than that of [Oiii] CELs and, therefore, that the abundance discrepancy may be closely linked to binary evolution.
The kinematical behavior of ORLs and CELs in PNe with [WC] central star
Authors: Peña Miriam , Ruiz-Escobedo Francisco , Rechy-García Jackeline , García-Rojas Jorge
Published: August 2017

In Planetary Nebulae (PNe) and HII regions ionic abundances can be derived by using collisionally excited lines (CELs) or recombination lines (ORLs). Such abundances do not coincide for the same ion and usually abundances from ORLs are larger than those from CELs by factors of 2 or larger. The origin of the discrepancy, known as the Abundance Discrepancy Factor is an open problem in astrophysics of gaseous nebulae. It has been attributed to temperature fluctuations in the plasma, tiny metal-rich inclusions embedded in the H-rich plasma, gas inhomogeneities or other processes. In this work we analyze the kinematical behavior of CELs and ORLs in two PNe ionized by [WC] stars, finding that kinematics of ORLS is incompatible with the kinematics of CELs. In particular the expansion velocities from CELs and ORLs for the same ion are different, indicating that ORLs seem to be produced in zones nearer the central star than CELs. This is in agreement with results found by other authors for individual PNe.
Magnetic fields in PNe and other evolved low-mass and intermediate-mass stars
Authors: Sabin Laurence , Zhang Qizhou , Wade Gregg A. , Lèbre Agnès , Vázquez Roberto
Published: August 2017

Magnetic fields are likely to be an efficient mechanism which can affect evolved intermediate mass stars (i.e. post-AGB stars and planetary nebulae) in different ways such as via the shaping of their envelope. However, observational probes for the presence of those fields are still scarce. I will present a summary of the works, including those from our group, on the detection and measurement of magnetic fields in various evolved objects.
Some Historical Notes
Authors: Torres-Peimbert Silvia
Published: August 2017

The study of planetary nebulae started more than a century ago. Since then the understanding of these exciting objects has advanced extraordinarily. I present a personal selection of topics to reflect on some developments of PNe research.
Modelling dust production in AGB stars
Authors: Dell’Agli Flavia
Published: August 2017

Asymptotic giant branch (AGB) stars are among the most important gas and dust polluters of the Universe. The latest AGB evolutionary models take into account dust production in the circumstellar envelope of these stars, starting from a detailed computation of the main physical processes and chemical surface variations occurring in this evolutionary phase. Following the formation and growth of dust particles, they provide the unique possibility of interpreting the AGB population observed in resolved galaxies. The first application was for the Spitzer observations of dusty AGBs in the Magellanic Clouds, characterising carbon-rich and oxygen-rich stars in terms of initial mass, epoch of star formation, evolutionary time on the AGB and dust contribution. The same set of models are able to interpret the CNO surface abundances observed for the PNe of the same galaxies.
The history of the Galactic bulge
Authors: Zijlstra A. A. , Gesicki K. , Bertolami M. M. Miller
Published: August 2017

Planetary nebulae form in stellar populations with ages from 1 to 10 Gyr, and can be used to trace their star formation histories. Here we apply this to the Galactic bulge, where there are indications both for an old origin and for younger stars. We use new stellar models, which have significant different evolutionary speeds during the post-AGB phase. We apply these new models to a sample of 32 planetary nebulae with HST imaging and VLT spectroscopy. The results show evidence for an old starburst, followed by continuous star formation until at least 2Gyr ago. This agrees very well with recent analysis of colour-magnitude diagrams of the bulge. We show that the new models can also explain the [OIII] luminosity functions, and predict the uniform luminosity cut-off both in spiral galaxies and old elliptical galaxies.
Photoionization models of Planetary Nebulae
Authors: Morisset Christophe
Published: August 2017

The understanding of astronomical nebulae is based on observational data (images, spectra, 3D data-cubes) and theoretical models. In this review, I present my very biased view on photoionization modeling of planetary nebulae, focusing on 1D multi-component models, on 3D models and on big database of models.
Stellar yields and abundances: new directions from planetary nebulae
Authors: Lugaro Maria , Karakas Amanda I. , Pignatari Marco , Doherty Carolyn L.
Published: August 2017

Planetary nebulae retain the signature of the nucleosynthesis and mixing events that occurred during the previous AGB phase. Observational signatures complement observations of AGB and post-AGB stars and their binary companions. The abundances of the elements heavier than iron such as Kr and Xe in planetary nebulae can be used to complement abundances of Sr/Y/Zr and Ba/La/Ce in AGB stars, respectively, to determine the operation of theslowneutron-capture process (thesprocess) in AGB stars. Additionally, observations of the Rb abundance in Type I planetary nebulae may allow us to infer the initial mass of the central star. Several noble gas components present in meteoritic stardust silicon carbide (SiC) grains are associated with implantation into the dust grains in the high-energy environment connected to the fast winds from the central stars during the planetary nebulae phase.
XSHOOTER spectroscopy of the enigmatic PN Lin49 in the SMC
Authors: Otsuka Masaaki , Kemper Francisca , Leal-Ferreira Marcelo L. , Aleman Isabel , Bernard-Salas Jeronimo , Cami Jan , Ochsendorf Bram B. , Peeters Els , Scicluna Peter
Published: August 2017

We performed a detailed spectroscopic analysis of the fullerene C60-containing planetary nebula (PN) Lin49 in the Small Magellanic Cloud (SMC). Lin49 is a C-rich and metal-deficient PN (Z~0.0006) and its nebular abundances are in agreement with the AGB model for the initially 1.25 M⊙ stars with the metallicity Z = 0.001. By stellar absorption fitting with TLUSTY, we derived stellar abundances, effective temperature, and surface gravity. We constructed the photoionization model with CLOUDY in order to investigate physical conditions of Lin49. The model with the 0.005-0.1 μm radius graphite and a constant hydrogen density shell could not fit the ~1-5 μm spectral energy distribution (SED) owing to the strong near-IR excess. We propose that the near-IR excess indicates (1) the presence of extremely small carbon molecules or (2) the presence of high-density structure surrounding the central star.
New models for the evolution of central stars of planetary nebulae: Faster and Brighter
Authors: Bertolami Marcelo M. Miller
Published: August 2017

The post-asymptotic giant branch (AGB) phase is arguably one of the least understood phases of the evolution of low- and intermediate- mass stars. The recent post-AGB evolutionary sequences computed by Miller Bertolami (2016) are at least three to ten times faster than those previously published by Vassiliadis & Wood (1994) and Blöcker (1995) which have been used in a large number of studies. This is true for the whole mass and metallicity range. The new models are also ~0.1–0.3 dex brighter than the previous models with similar remnant masses. In this short article we comment on the main reasons behind these differences, and discuss possible implications for other studies of post-AGB stars or planetary nebulae.
The population of planetary nebulae near the Galactic Centre: chemical abundances
Authors: Mollá M. , Cavichia O. , Costa R. D. D. , Maciel W. J.
Published: August 2017

In this work, we report physical parameters and abundances derived for a sample of 15 high extinction planetary nebulae located in the inner 2° of the Galactic bulge, based on low dispersion spectroscopy secured at the SOAR telescope using the Goodman spectrograph. The new data allow us to extend our database including older, weaker objects that are at the faint end of the planetary nebulae luminosity function. The data provide chemical compositions for PNe located in this region of the bulge to explore the chemical enrichment history of the central region of the Galactic bulge. The results show that the abundances of our sample are skewed to higher metallicities than previous data in the outer regions of the bulge. This can indicate a faster chemical enrichment taking place at the Galactic centre.
3D Hydrodynamical models of the planetary nebulae M 1-32 and M 3-15
Authors: Rechy-García Jackeline S. , Velázquez Pablo F. , Peña Miriam , Raga Alejandro C.
Published: August 2017

High-resolution, long-slit spectroscopic observations of two planetary nebulae, M1-32 and M3-15 are presented. The observations were obtained with the 2.1-m telescope at the OAN-SPM, and MES spectrograph. M1-32 shows wide wings on the base of its emission lines and M3-15 has two very faint high-velocity knots. To model both PNe we built a 3D model consisting in a jet interacting with an equatorially concentrated slow wind, emulating the presence of a dense torus, by using the hydrodynamical code Yguazú. The synthetic position-velocity (PV) diagrams obtained from our models reproduce well the observed PV diagrams.
Where are the binaries in proto-planetary nebulae? Results of a long-term radial velocity study
Authors: Hrivnak Bruce J. , Van Winckel Hans , Van de Steene Griet , Bohlender David , Sperauskas Julius , Lu Wenxian
Published: August 2017

We present the results of a long-term search (25 yrs) for radial velocity variability in a sample of seven bright proto-planetary nebulae showing axial symmetry. They all vary in velocity due to periodic pulsations. However, only marginal evidence is found for multi-year variations that might be due to a binary companion.
Close binary central stars and the abundance discrepancy - new extreme objects
Authors: Wesson R. , Jones D. , García-Rojas J. , Corradi R. L. M. , Boffin H. M. J.
Published: August 2017

Recent work (Corradi et al. 2015; Jones et al. 2016) has shown that the phenomenon of extreme abundance discrepancies, where recombination line abundances exceed collisionally excited line abundances by factors of 10 or more, seem to be strongly associated with planetary nebulae with close binary central stars. To further investigate, we have obtained spectra of a sample of nebulae with known close binary central stars, using FORS2 on the VLT, and we have discovered several new extreme abundance discrepancy objects. We did not find any non-extreme discrepancies, suggesting that a very high fraction of nebulae with close binary central stars also have an extreme abundance discrepancy.
Gaia and the Planetary Nebulae
Authors: Manteiga Minia , Dafonte Carlos , Álvarez Marco A. , Garabato Daniel , Ulla Ana , Jordi Carme
Published: August 2017

About three years after Gaia was set into orbit, the first release of Gaia data, DR1, has been published by ESA and DPAC. Gaia’s first archive contains the results from the analysis of the initial 14 months of mission data. Outstandingly, it includes TGAS, Gaia-Tycho2 astrometric solution for about 2 million stars up to visible magnitude around 11.5.

In addition to the five parameter astrometric solution for the sky (positions, parallaxes and proper motions), future Gaia data releases will provide the spectral energy distributions from 330-1050 nm, together with radial velocities, for sources brighter than visible magnitude 16. Within this context, the relevance of Gaia data for the study of PN is be briefly presented.
Post-common envelope PN, fundamental or irrelevant?
Authors: De Marco Orsola , Reichardt T. , Iaconi R. , Hillwig T. , Jacoby G. H. , Keller D. , Izzard R. G. , Nordhaus J. , Blackman E. G.
Published: August 2017

One in 5 PN are ejected from common envelope binary interactions butKeplerresults are already showing this proportion to be larger. Their properties, such as abundances can be starkly different from those of the general population, so they should be considered separately when using PN as chemical or population probes. Unfortunately post-common envelope PN cannot be discerned using only their morphologies, but this will change once we couple our new common envelope simulations with PN formation models.
Study of protoplanetary nebulae
Authors: Estrella D. , Hernández-Martínez L. , Velázquez P. F. , Esquivel A. , Raga C. A.
Published: August 2017

We have performed 3D hydrodynamic simulations of a symmetrical jet ejection following previous works (Raga et al. 2009, Riera et al. 2014, Velázquez et al. 2014). The jet is emitted from a binary system in elliptical orbit, and its direction changes describing a precession cone. We have considered that the jet has a time-dependence density ejection or a time-dependence velocity ejection, in order to propose an alternative model to explain the morphology of PPNe’s. Also in our description we have included the effect of the photoionization of the central source. From numerical results, synthetic Hα maps were obtained, and a proper motion study were carried out. We found that the photoionization has an important effect on the case with variation density resulting in a increse in the Hα emission.
Gaia: mapping the dynamics and morphologies of Galactic Planetary Nebulae: First results from Gaia Data Release 1
Authors: Walton Nicholas A. , Rejkuba Marina , Walsh Jeremy R. , Zijstra Albert A.
Published: August 2017

This paper comments on the use Gaia in studying the internal dynamics and morphologies of Planetary Nebulae (PN). It is noted that the second and subsequent releases of Gaia data, will have significant potential in unravelling PN morphologies.