bluuebunny/crossref_metadata_2025 huggingface dataset:
The Cost of Providing District‐Level Surgery in Malawi
Authors: Cornelissen Dennis , Mwapasa Gerald , Gajewski Jakub , McCauley Tracey , Borgstein Eric , Brugha Ruairi , Bijlmakers Leon
Published: August 2017

Background

Three district hospitals in Malawi that provide essential surgery, which for many patients can be lifesaving or prevent disability, formed the setting of this costing study.

Methods

All resources used at district hospitals for the delivery of surgery were identified and quantified. The hospital departments were divided into three categories of cost centres—the final cost centre, intermediate and ancillary cost centres. All costs of human resources, buildings, equipment, medical and non‐medical supplies and utilities were quantified and allocated to surgery through step‐down accounting.

Results

The total cost of surgery, including post‐operative care, ranged from US$ 329,000 per year to more than twice that amount at one of the hospitals. At two hospitals, it represented 16–17% of the total cost of running the hospital. The main cost drivers of surgery were transport and inpatient services, including catering. The cost of a C‐section ranged from $ 164 to 638 that of a hernia repair from $ 137 to 598. Evacuations from uterus were cheapest mainly because of the shorter duration of patient stay.

Conclusion

Low bed occupancy rates and utilisation rates of the operating theatres suggest overcapacity but may also indicate a potential to scale up surgery. This may be achieved by adding surgical staff, although there may be rate‐limiting steps, such as demand for surgery in the community or capacity to provide anaesthesia. If a scale‐up of surgery cannot be realised, hospital managers may be forced to reduce the number of beds, reorganise wards and/or reallocate staff to achieve better economies of scale.
Surgical Resources in South Africa: An International Comparison and Deficit Calculation
Authors: Dell A. J. , Kahn D.
Published: August 2017

Background

Surgical conditions lead to premature death and disability resulting in a massive economic burden. Contributing to this global crisis is the lack of data on the limited surgical infrastructure and workforce in many low‐ and middle‐income countries.

Methods

This study involved a descriptive analysis of surgical resources in South Africa and included the total number of hospitals, number of hospital beds, number of surgical beds, number of general surgeons, and the number of functional operating theatres. All hospitals in South Africa were contacted between the 1 October 2014 and the 31 December 2014. An international comparison of South Africa’s surgical resources was then made with several countries.

Results

The results showed one hospital per 100,000 population. There were 186.64 hospital beds, 41.55 surgical beds, 1.78 specialist general surgeons, 2.90 non‐specialist general surgeons, and 3.59 operating theatres per 100,000 people in South Africa. These numbers fell far below international recommendations, as well as for developed countries such as the UK and USA.

Conclusion

Strengthening surgical systems will reduce the surgical burden of disease and improve health outcomes globally. This description of surgical infrastructure and workforce provided insight into the surgical capacity of South Africa. Furthermore, this research provided a comparison of surgical resources between South Africa and the rest of the world.
Minimally Invasive Pancreaticoduodenectomy: What is the Best “Choice”? A Systematic Review and Network Meta‐analysis of Non‐randomized Comparative Studies
Authors: Ricci Claudio , Casadei Riccardo , Taffurelli Giovanni , Pacilio Carlo Alberto , Ricciardiello Marco , Minni Francesco
Published: August 2017

Background

Many mini‐invasive pancreaticoduodenectomy (MIPD) techniques have been reported, but their advantages with respect to an open technique (OPD) and with respect to each other are unclear.

Method

A systematic literature search of studies comparing different types of MIPD was carried out: laparoscopic‐assisted (LAPD), totally robotic (TRPD), totally laparoscopic (TLPD) or totally laparoscopic—robotic assisted (TLPD‐RA) to OPD. The primary endpoint was postoperative mortality. The secondary endpoints were intraoperative, postoperative and oncological outcomes. A network meta‐analysis was designed to generate direct, indirect and mixed estimate effects, between different approaches, for each variable. The effects were reported as pairwise comparisons and hierarchical ranking as to each approach could be the best or the worst for each outcome, expressed by the surface under the cumulative ranking curve.

Results

Twenty studies were identified, involving 2759 patients: 1813 OPDs, 81 LAPDs, 505 TRPDs, 224 TLPDs and 136 TLPD‐RAs. No differences regarding postoperative mortality were found in pairwise comparison. The LAPD technique had a high probability of being the worst approach, while TRPD had a high probability of being one of the best. Regarding the secondary endpoints, OPD was the best regarding operative time and postoperative bleeding, but the worst regarding blood loss and wound infection. The TRPD or TLPD‐RA techniques seemed to be the best for delayed gastric emptying, length of hospital stay, harvested lymph nodes and postoperative morbidity. The TLPD technique was often the worst approach, especially for overall and major complications, postoperative bleeding and biliary leak.

Conclusion

The safest MIPDs are those involving a robotic system which seems to have a promising role in ameliorating the outcomes of OPD, especially when compared to a laparoscopic approach.
Learning from the UK’s research impact assessment exercise: a case study of a retrospective impact assessment exercise and questions for the future
Authors: Morgan Jones Molly , Manville Catriona , Chataway Joanna
Published: August 2017

National governments spend significant amounts of money supporting public research. However, in an era where the international economic climate has led to budget cuts, policymakers increasingly are looking to justify the returns from public investments, including in science and innovation. The so-called ‘impact agenda’ which has emerged in many countries around the world is part of this response; an attempt to understand and articulate for the public what benefits arise from the research that is funded. The United Kingdom is the most progressed in implementing this agenda and in 2014 the national research assessment exercise, the Research Excellence Framework, for the first time included the assessment of research impact as a component. For the first time within a dual funding system, funding would be awarded not only on the basis of the academic quality of research, but also on the wider impacts of that research. In this paper we outline the context and approach taken by the UK government, along with some of the core challenges that exist in implementing such an exercise. We then synthesise, together for the first time, the results of the only two national evaluations of the exercise and offer reflections for future exercises both in the UK and internationally.
COMBAT study – Computer based assessment and treatment – A clinical trial evaluating impact of a computerized clinical decision support tool on pain in cancer patients
Authors: Raj Sunil X. , Brunelli Cinzia , Klepstad Pål , Kaasa Stein
Published: August 2017

Background and aims

The prevalence of pain in cancer patients are relatively high and indicate inadequate pain management strategies. Therefore, it is necessary to develop new methods and to improve implementation of guidelines to assess and treat pain. The vast improvement in information technology facilitated development of a computerized symptom assessment and decision support system (CCDS) - the Combat system - which was implemented in an outpatient cancer clinic to evaluate improvement in pain management.

Methods

We conducted a controlled before-and-after study between patient cohorts in two consecutive study periods: before (n = 80) and after (n = 134) implementation of the Combat system. Patients in the first cohort completed questionnaires with the paper-and-pencil method and this data was not shown to physicians. Patients in the latter cohort completed an electronic questionnaire by using an iPad and the data were automatically transferred and presented to physicians at point of care. Additionally, the system provided computerized decision support at point of care for the physician based on the electronic questionnaires completed by the patients, an electronic CRF completed by physicians and clinical guidelines.

Results

The Combat system did not improve pain intensity and there were no significant alterations in the prescribed dose of opiates compared to the cohort of patients managed without the Combat system.

Conclusion

The Combat system did not improve pain management. This may be explained by several factors, however, we consider lack of proper implementation of the CCDS in the clinic to be the most important factor. As a result, we did not manage to change the behaviour of the physicians in the clinic.

Implications

There is a need to conduct larger prospective studies to evaluate the efficacy of modern information technology to improve pain management in cancer patients. Before introducing new information technology in the clinics, it is important to have a well thought out implementation strategy. The trial is registered at Clinialtrials.gov, number NCT01795157.
Effectiveness of Disinfectants Against Candida auris and Other Candida Species
Authors: Cadnum Jennifer L. , Shaikh Aaron A. , Piedrahita Christina T. , Sankar Thriveen , Jencson Annette L. , Larkin Emily L. , Ghannoum Mahmoud A. , Donskey Curtis J.
Published: August 2017

Contaminated surfaces are a suspected source for dissemination of the globally emerging pathogen Candida auris. In laboratory testing, sporicidal and improved hydrogen peroxide disinfectants were highly effective against C. auris, C. glabrata, and C. albicans. The widely used quaternary ammonium disinfectants exhibited relatively poor activity against all of the Candida species.

Infect Control Hosp Epidemiol 2017;38:1240–1243
DE-CENTERING CHINESE HISTORY
Authors: Herman John E.
Published: August 2017

What would Chinese history look like if we were to examine it from the perspective of the peoples living along China's periphery? How might a non-Chinese perspective challenge the dominant themes in Chinese historiography, themes which represent Chinese history as a linear narrative arising from the Central Plain and its original inhabitants, the Han Chinese? If, for example, we rely solely on Chinese sources to tell us about Chinese-Jurchen/Manchu relations during the first half of the seventeenth century, we will have privileged Chinese sources, affirmed the authority of the Chinese perspective, and suppressed voices that might offer an alternative perspective. Only an aggressive deconstruction of such “authoritative” Chinese texts can expose biases and logical inconsistencies, unpack cultural tensions that demand more rigorous scrutiny, and tease out into the open silenced voices from spaces buried deep in the text. Those historians who engage in such a methodological approach, however, run the risk of being accused of applying fanciful postmodernist conjecture or presentist interpretations to the past. This is why the recent (since the 1980s) addition of Manchu language sources to our examination of Qing history (1636–1912) has had such a seismic impact on the field.
Role of overturns in optimal mixing in stratified mixing layers
Authors: Mashayek A. , Caulfield C. P. , Peltier W. R.
Published: August 2017

Turbulent mixing plays a major role in enabling the large-scale ocean circulation. The accuracy of mixing rates estimated from observations depends on our understanding of basic fluid mechanical processes underlying the nature of turbulence in a stratified fluid. Several of the key assumptions made in conventional mixing parameterizations have been increasingly scrutinized in recent years, primarily on the basis of adequately high resolution numerical simulations. We add to this evidence by compiling results from a suite of numerical simulations of the turbulence generated through stratified shear instability processes. We study the inherently intermittent and time-dependent nature of wave-induced turbulent life cycles and more specifically the tight coupling between inherently anisotropic scales upon which small-scale isotropic turbulence grows. The anisotropic scales stir and stretch fluid filaments enhancing irreversible diffusive mixing at smaller scales. We show that the characteristics of turbulent mixing depend on the relative time evolution of the Ozmidov length scale$L_{O}$compared to the so-called Thorpe overturning scale$L_{T}$which represents the scale containing available potential energy upon which turbulence feeds and grows. We find that when$L_{T}\sim L_{O}$, the mixing is most active and efficient since stirring by the largest overturns becomes ‘optimal’ in the sense that it is not suppressed by ambient stratification. We argue that the high mixing efficiency associated with this phase, along with observations of$L_{O}/L_{T}\sim 1$in oceanic turbulent patches, together point to the potential for systematically underestimating mixing in the ocean if the role of overturns is neglected. This neglect, arising through the assumption of a clear separation of scales between the background mean flow and small-scale quasi-isotropic turbulence, leads to the exclusion of an highly efficient mixing phase from conventional parameterizations of the vertical transport of density. Such an exclusion may well be significant if the mechanism of shear-induced turbulence is assumed to be representative of at least some turbulent events in the ocean. While our results are based upon simulations of shear instability, we show that they are potentially more generic by making direct comparisons with$L_{T}-L_{O}$data from ocean and lake observations which represent a much wider range of turbulence-inducing physical processes.
Natural convection and thermal drift
Authors: Abtahi Arman , Floryan J. M.
Published: August 2017

An analysis of natural convection in a horizontal, geometrically non-uniform slot exposed to spatially non-uniform heating has been carried out. The upper plate is smooth and isothermal, and the lower plate has sinusoidal corrugations with a sinusoidal temperature distribution. The distributions of the non-uniformities are characterized in terms of the wavenumber$\unicode[STIX]{x1D6FC}$and their relative position is expressed in terms of the phase difference$\unicode[STIX]{x1D6FA}_{TL}$. The analysis is limited to heating conditions which do not give rise to secondary motions in the absence of the non-uniformities. The heating creates horizontal temperature gradients which lead to the formation of vertical and horizontal pressure gradients which drive the motion regardless of the intensity of the heating. When the hot spots (points of maximum temperature) overlap either with the corrugation tips or with the corrugation bottoms, convection assumes the form of pairs of counter-rotating rolls whose size is dictated by the heating/corrugation wavelengths. The formation of a net horizontal flow, referred to as thermal drift, is observed for all other relative positions of the hot spots and corrugation tips. Both periodic heating as well as periodic corrugations are required for the formation of this drift, which can be directed in the positive as well as in the negative horizontal directions depending on the phase difference between the heating and corrugation patterns. The most intense convection and the largest drift occur for wavelengths comparable to the slot height, and their intensities increase proportionally to the heating intensity as well as proportionally to the corrugation amplitude, with the drift being a very strong function of the phase difference. Convection creates forces at the plates which would cause horizontal displacement of the corrugated plate and deform the corrugations if such effects were allowed. Tangential forces generated by the uniform heating always contribute to the corrugation buildup while similar forces generated by the periodic heating contribute to the buildup only when the hot spots overlap with the upper part of the corrugation. The processes described above are qualitatively similar for all Prandtl numbers$Pr$, with the intensity of convection and the magnitude of the drift increasing with a reduction in$Pr$.
A Learning Collaborative Model for Implementation of Smoking Cessation among Homeless Veterans
Authors: Beckham Jean C. , Kirby Angela C. , Tise Nick , Carpenter Vickie L. , Dedert Eric A. , McNiel J. Murray , Runnals Jennifer J. , Calhoun Patrick S.
Published: August 2017

We evaluated the feasibility of incorporating integrated care (IC) for smoking cessation into routine care for homeless veterans at seven Department of Veterans Affairs (VA) Medical Centers and the utility of the learning collaborative (LC) model in facilitating implementation. The goal of IC is for clinicians to provide smoking cessation concurrent with other clinical duties. The LC model utilises multidisciplinary teams and recognised field experts to develop methods for accelerating the use of evidence-based treatments. Multidisciplinary teams comprising 34 (of about 175) staff members from seven VA homeless provider teams participated. Via self-report questionnaires, we assessed providers’ perceptions of the LC and the number of providers delivering IC. Nineteen of thirty-four providers (54%) reported delivering IC at the end of training and at 10-months. Providers rated the face-to-face trainings and collaborative team trainings as the most helpful LC components. Barriers to the use of the LC included lack of leadership support and the lack of ability to electronically track progress through the electronic medical record. Additional research, quality improvement, and policy changes at higher administrative levels are needed to identify methods to sustain the use of LC among providers serving homeless veterans.
FUNCTIONAL VERSIONS OF SOME REFINED AND REVERSED OPERATOR MEAN INEQUALITIES
Authors: RAÏSSOULI MUSTAPHA
Published: August 2017

We present refined and reversed inequalities for the weighted arithmetic mean–harmonic mean functional inequality. Our approach immediately yields the related operator versions in a simple and fast way. We also give some operator and functional inequalities for three or more arguments. As an application, we obtain a refined upper bound for the relative entropy involving functional arguments.
From soft sediment deformation to fluid assisted faulting in the shallow part of a subduction megathrust analogue: the Sestola Vidiciatico tectonic Unit (Northern Apennines, Italy)
Authors: MITTEMPERGHER SILVIA , CERCHIARI ANNA , REMITTI FRANCESCA , FESTA ANDREA
Published: August 2017

The Sestola Vidiciatico tectonic Unit (SVU) accommodated the early Miocene convergence between the subducting Adriatic plate and the overriding Ligurian prism, and has been interpreted as a field analogue for the shallow portion of subduction megathrusts. The SVU incorporated sediments shortly after their deposition and was active down to burial depth corresponding to temperatures around 150 °C. Here, we describe the internal architecture of the basal thrust fault of the SVU through a multi-scale structural analysis and investigate the evolution of the deformation mechanisms with increasing burial depth. At shallow depth, the thrust developed in poorly lithified sediments which deformed by particulate flow. With increasing depth and lithification of sediments, deformation was accommodated in a meter scale, heterogeneous fault zone, including multiple strands of crack-and-seal shear veins, associated with minor distributed shearing in clay-rich domains and pressure solution. In the last stage, slip localized along a sharp, 20 cm thick shear vein, deactivating the fault zone towards the footwall. The widespread formation of crack-and-seal shear veins since the first stages of lithification indicates that failure along the thrust occurred at high fluid pressure and low differential stress already at shallow depth. Progressive shear localization occurs in the last phases of deformation, at temperatures typical of the transition to the seismogenic zone in active megathrusts.
One new species ofPistaMalmgren, 1866 (Annelida: Terebellidae) and one new species ofPistellaHartmann-Schröder, 1996 (Annelida: Terebellidae) from the Adriatic Sea (Mediterranean)
Authors: Mikac Barbara , Hutchings Pat
Published: August 2017

During several sampling periods in the Northern Adriatic Sea (Mediterranean) from 2003–2010, one species ofPistaand one ofPistellawere found. They were initially identified asPistacf.lornensis(Pearson, 1969), but detailed examination revealed the presence of two new species, one belonging to the genusPistellaHartmann-Schröder, 1996,P. rovignensissp. nov. and one belonging to the genusPista,P. adriaticasp. nov. These two species differ from each other in the structure of the branchiae, shape of lateral lobes and the structure of the anterior thoracic uncini. The two new species are compared with other species ofPistellaandPistacurrently known. The relationship ofPistellaandPistais confusing and a complete revision of the two genera is urgently needed together with other genera characterized by having long-handled thoracic uncini.
Doing natural theology consistently with theism and why one might stop trying
Authors: MAWSON T. J.
Published: August 2017

Theists such as Swinburne who seek to use natural theological arguments to move from observations about the world to conclusions about the existence (or probable existence) of God seem to need premises concerning what the world would have been like were Theism to have been false, viz. premises to the effect that it would have been (or would probably have been) different from the way we observe the actual world to be. Surely only that way could observations of the actual world be taken to be evidence that Theism is true.1 And surely for such arguments to be dialectically powerful in discussions with Atheists, these premises need to be acceptable to Theists and Atheists alike.2 In this article, I call these claims into question.
Reply to my commentators
Authors: SWINBURNE RICHARD
Published: August 2017

This article contains my responses to the discussions of my views on the nature of God by Howard Robinson and Herman Philipse, my views on the strength of arguments for the existence of God by Herman Philipse, Brian Leftow, Timothy Mawson, and Christoph Jäger, and my views on the nature and justification of Christian faith by Mark Wynn and Cyrille Michon, contained in this issue of Religious Studies.
Herman Bavinck's Reformed eclecticism: On catholicity, consciousness and theological epistemology
Authors: Brock Cory , Sutanto Nathaniel Gray
Published: August 2017

This article argues that Herman Bavinck's organic worldview allows him to use classical and modern thinkers in an eclectic yet theologically principled manner. To vindicate this claim, the article observes Bavinck's self-conscious comments regarding the task of Reformed catholicity, his use of Schleiermacher and Augustine to construct a theological account of self-consciousness, and his resituating of Thomistic motifs within an organic framework in his epistemology. In so doing, the article suggests that Bavinck's catholicity is broader than previously observed, thus generating a different way of interpreting Bavinck's use of thinkers who are often thought to be in tension.
Enacting the Consequences of the Lecoq Pedagogy's Aesthetic Cognitive Foundation
Authors: Murphy Maiya
Published: August 2017

The theatre pedagogy of Jacques Lecoq (1921–99) is founded on the principle that all physical, psychological, intellectual, and emotional performance registers can be accessed by prioritizing the moving body. Therefore, a Lecoq-based approach is in contrast to dominant principles of psychologically based acting that privilege working through emotion and psychology. While Lecoq pedagogy does not discount these performance registers, normally considered to belong to the “internal” world of the actor, Lecoq's work reaches them through physical action. Lecoq pedagogy considers it possible to learn how to shape and manage these registers by mastering the moving body as creative theatrical agent. This pedagogical strategy at first reiterates and then inverts the mind privilege of a Cartesian mind–body dichotomy, but ultimately confounds it, reorienting the constitution of body and mind. This reconstitution results in a new, emergent, antidualistic configuration where somatic intelligence accesses and encompasses all intelligence, and is initiated and accomplished through the physical act.
Being Autonomous and Having Space in which to Act: Commissioning in the ‘New NHS’ in England
Authors: CHECKLAND KATH , DAM RINITA , HAMMOND JON , COLEMAN ANNA , SEGAR JULIA , MAYS NICHOLAS , ALLEN PAULINE
Published: August 2017

The optimal balance between central governmental authority and the degree of autonomy of local public bodies is an enduring issue in public policy. The UK National Health Service is no exception, with NHS history, in part at least, a history of repeated cycles of centralisation and decentralisation of decision-making power. Most recently, a significant reorganisation of the NHS in 2012–13 was built around the creation of new and supposedly more autonomous commissioning organisations (Clinical Commissioning Groups – CCGs). Using Bossert's (1998) concept of ‘decision space’, we explored the experiences of local commissioners as they took on their new responsibilities. We interviewed commissioning staff from all of the CCGs in two regional health care ‘economies’, exploring their perceptions of autonomy and their experiences over time. We found significant early enthusiasm for, and perceptions of, increased autonomy tempered in the vertical dimension by increasingly onerous and prescriptive monitoring regimes, and in the horizontal dimension by the proliferation of overlapping networks, inter-organisational groups and relationships. We propose that, whatever the balance between central and local control that is adopted, complex public services require some sort of meso-level oversight from organisations able to ‘hold the ring’ between competing interests and to take a regional view of the needs of the local health system. This suggests that local organisational autonomy in such services will always be constrained.
GV/cm scale laser-magnetic resonant acceleration in vacuum
Authors: Zhang Y. , Jiao J.-L. , Zhang B. , Zhang Z.-M. , Gu Y.-Q.
Published: August 2017

Resonant acceleration of electrons by a laser in the background of an extra longitudinal magnetic field is investigated analytically and numerically. The resonant condition is independent of laser intensity, and when satisfied, the energy gain is proportional to $a_0^2 $ and the square of phase difference. This process is mainly limited by the magnitude and spatial size of the extra magnetic field. Under the laboratory conditions, simulation results show that a monoenergetic and collimated electron bunch can still be obtained in ~ GV/cm scale, which sheds a light on the vacuum table-top laser-driven electron accelerators.
Centralizing Trends and Pollution Law Enforcement in China
Authors: van Rooij Benjamin , Zhu Qiaoqiao , Na Li , Qiliang Wang
Published: August 2017

This article analyses centralizing trends that may be able to reduce the negative influence of local protectionism on environmental law enforcement in China. The article finds that as centralizing trends unfolded, enforcement over time has become stricter and more frequent, however with only minor effects in reducing pollution. Moreover it finds a situation of uneven enforcement with richer and more urbanized areas having much stronger and more frequent enforcement than inland areas. Centralizing trends may thus have spurred stronger enforcement, but concurrently allowed for an uneven enforcement. At the same time, the article finds a continued local influence, keeping enforcement too weak to have much effect in reducing pollution and allowing for local interests to shape enforcement into unequal outcomes.
Relationship between apoptosis and survival molecules in human cumulus cells as markers of oocyte competence
Authors: Bosco Liana , Chiarelli Roberto , Roccheri Maria Carmela , Matranga Domenica , Ruvolo Giovanni
Published: August 2017

To select from a single patient the best oocytes able to reach the blastocyst stage, we searched for valuable markers for oocytes competence. We evaluated the DNA fragmentation index (DFI) and the level of some survival molecules, such as AKT, pAKT and pERK1/2, in individual cumulus cell–oocyte complexes (COC). The study included normo-responder women. The average age of the patients was 34.3. DFI in cumulus cells was evaluated using the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) assayin situ. AKT, pAKT and pERK1/2 were measured by immunological assay and densitometric analysis of fluorescent signals using NIS-Elements BR 3.10 image software. Statistical analysis was performed using STATA SE/14.1. The study focused on 53 patients involved after informed consent. Out of 255 MII oocytes, 197 were fertilized and the derived embryos had the following evolution: 117 completed the development to blastocyst and were transferred to uterus; 57 were vitrified at the blastocyst stage; and 23 were arrested duringin vitroculture at different stages of cleavage. We found a significant statistical difference between the DFI of cumulus cells of the arrested embryos and the transferred blastocysts (P= 0.004), confirming that DFI could be considered as a valuable marker of oocyte competence. In addition, the pAKT/DFI ratio was higher in cumulus cells of oocytes able to produce blastocysts, indicating that DFI is significantly lower when pAKT is higher (P= 0.043). This study demonstrates for the first time that the relationship between apoptosis and survival molecules can be used as a marker to select the best oocytes.
Reconstruction of Laser-Induced Surface Topography from Electron Backscatter Diffraction Patterns
Authors: Callahan Patrick G. , Echlin McLean P. , Pollock Tresa M. , De Graef Marc
Published: August 2017

We demonstrate that the surface topography of a sample can be reconstructed from electron backscatter diffraction (EBSD) patterns collected with a commercial EBSD system. This technique combines the location of the maximum background intensity with a correction from Monte Carlo simulations to determine the local surface normals at each point in an EBSD scan. A surface height map is then reconstructed from the local surface normals. In this study, a Ni sample was machined with a femtosecond laser, which causes the formation of a laser-induced periodic surface structure (LIPSS). The topography of the LIPSS was analyzed using atomic force microscopy (AFM) and reconstructions from EBSD patterns collected at 5 and 20 kV. The LIPSS consisted of a combination of low frequency waviness due to curtaining and high frequency ridges. The morphology of the reconstructed low frequency waviness and high frequency ridges matched the AFM data. The reconstruction technique does not require any modification to existing EBSD systems and so can be particularly useful for measuring topography and its evolution duringin situexperiments.
In Situ Thermal Annealing Transmission Electron Microscopy (TEM) Investigation of III/V Semiconductor Heterostructures Using a Setup for Safe Usage of Toxic and Pyrophoric Gases
Authors: Straubinger Rainer , Beyer Andreas , Ochs Thomas , Stolz Wolfgang , Volz Kerstin
Published: August 2017

In this study we compare two thermal annealing series of III/V semiconductor heterostructures on Si, where during the first series nitrogen is present in the in situ holder. The second, comparative, measurement is done in a tertiarybutylphosphine (TBP) environment. The sample annealed in a TBP environment shows favorable thermal stability up to 500°C compared to the unstabilized sample, which begins to degrade at less than 300°C. Evaporation of P from the material is tracked qualitatively by measuring the thickness of the sample during thermal annealing with and without stabilization. Finally, we investigate the in situ thermal annealing processes at atomic resolution. Here it is possible to study phase separation as well as the diffusion of As from a Ga(NAsP) quantum well in the surrounding GaP material during thermal annealing. To make these investigations possible we developed an extension for our in situ transmission electron microscopy setup for the safe usage of toxic and pyrophoric III/V semiconductor precursors. A commercially available gas cell and gas supply system were expanded with a gas mixing system, an appropriate toxic gas monitoring system and a gas scrubbing system. These components allow in situ studies of semiconductor growth and annealing under the purity conditions required for these materials.
Combating Social Exclusion Faced by Disabled People in the Wage Labour Market in Hong Kong
Authors: Chau Ruby C. M. , Yu Sam W. K. , Boxall Kathy
Published: August 2017

This article contributes to the search for suitable approaches to combat social exclusion faced by disabled people in capitalist wage labour markets. Referring to policy and service examples in Hong Kong, it reviews four social exclusion approaches – the Moral Underclass (MUD), Social Integrationist (SID), Redistributive (RED) and Collective Production (COP) approaches. These approaches are explored in relation to three key issues: (1) the diverse preferences of disabled people; (2) the myth of infeasibility regarding unconventional approaches and (3) the defects of the medical model of disability. The article argues that the MUD and SID approaches are more associated with the medical model of disability and emphasise individual changes. The RED and COP approaches contain more features of the social model of disability and are in favour of social and structural changes. The COP approach stresses the diverse preferences of disabled people and supports innovative services to combat social exclusion.
Abundances and gradients in nearby galaxies
Authors: Bresolin Fabio
Published: August 2017

The study of chemical abundance gradients can provide essential information on the evolution of disk galaxies. Here I briefly review our current observational knowledge concerning the abundances of the ionized gas (H ii regions and planetary nebulae) in nearby galaxies, and how they inform us about the time evolution of metallicity gradients.
Planetary nebulae as kinematic tracers of galaxy stellar halos
Authors: Coccato Lodovico
Published: August 2017

The kinematic and dynamical properties of galaxy stellar halos are difficult to measure because of the faint surface brightness that characterizes these regions. Spiral galaxies can be probed using the radio Hiemission; on the contrary, early-type galaxies contain less gas, therefore alternative kinematic tracers need to be used. Planetary nebulae (PNe) can be easily detected far out in the halo thanks to their bright emission lines. It is therefore possible to map the halo kinematics also in early-type galaxies, typically out to 5 effective radii or beyond. Thanks to the recent spectroscopic surveys targeting extra-galactic PNe, we can now rely on a few tens of galaxies where the kinematics of the stellar halos are measured. Here, I will review the main results obtained in this field in the last decades.
3He Abundances in Planetary Nebulae
Authors: Guzman-Ramirez Lizette
Published: August 2017

Determination of the 3He isotope is important to many fields of astrophysics, including stellar evolution, chemical evolution, and cosmology. The isotope is produced in stars which evolve through the planetary nebula phase. Planetary nebulae are the final evolutionary phase of low- and intermediate-mass stars, where the extensive mass lost by the star on the asymptotic giant branch is ionised by the emerging white dwarf. This ejecta quickly disperses and merges with the surrounding ISM. 3He abundances in planetary nebulae have been derived from the hyperfine transition of the ionised 3He, 3He+, at the radio rest frequency 8.665 GHz. 3He abundances in PNe can help test models of the chemical evolution of the Galaxy. Many hours have been put into trying to detect this line, using telescopes like the Effelsberg 100m dish of the Max Planck Institute for Radio Astronomy, the National Radio Astronomy Observatory (NRAO) 140-foot telescope, the NRAO Very Large Array, the Arecibo antenna, the Green Bank Telescope, and only just recently, the Deep Space Station 63 antenna from the Madrid Deep Space Communications Complex.
The PN.S ETG survey
Authors: Arnaboldi M. , Pulsoni C. , Gerhard O. ,   PN.S Consortium
Published: August 2017

We have analyzed the velocity fields in the halos of thirty-three early-type galaxies (ETGs) with planetary nebulae (PNs) as tracers, reaching radii of up to ~8Re. The sample comprises twenty-five galaxies from the Planetary Nebulae Spectrograph (PN.S) ETG survey and eight further galaxies with extended PN velocity data from the literature and new Counter-Dispersed imaging observations. The catalogues from these thirty-three ETGs provide astrometric positions and heliocentric line-of-sight velocities for a total of 8354 extragalactic PNs. All these catalogues are treated homogeneously for the identification of kinematic outliers and the separation between main galaxy/satellites in each galaxy field-of-view. We discuss the rotation velocities, velocity dispersion profiles and radial trends of the specific angular momentum, separating between slow rotators and fast rotators. We compare the properties of the V/σ(R) and σ(R) profiles with predictions of 2D velocity fields from hydro-dynamical cosmological simulations. We briefly mention the possible origin of the quasi-Keplerian steeply decreasing profile galaxies which encompasses about one fourth of the current sample.
The kinematics of the nebular shells around low mass progenitors of PNe with low metallicity
Authors: Pereyra Margarita , López José Alberto , Richer Michael G.
Published: August 2017

In the past few years we provided strong observational support for theoretical studies regarding the internal kinematics of Planetary Nebulae (PNe). A total of 257 objects segregated by different galactic populations were analized. Based upon spatially-resolved, long-slit, echelle spectroscopy drawn from the San Pedro Mártir Kinematic Catalogue of PNe†, we characterized the kinematics of PNe shells measuring their global expansion velocities. We present here a brief summary of these observational results, with a focus on our most recent study of about 26 PNe with low metallicity that appear to derive from progenitor stars of the lowest masses (including the halo PNe population). Low expansion velocities were found for these nebulae, less than 20 km s−1, which are most likely associated with a weak central star wind driving the kinematics of the nebular shell in this particular population.
Exploring the transition into an asymmetric planetary nabulae
Authors: Cárdenas Mónica W. Blanco , Vázquez Roberto , Kaeufl Hans Ulrich , Gómez-Muñoz Marco A. , Guillén Pedro F. , Guerrero Martín A. , Miranda Luis F.
Published: August 2017

We present studies using different observational techniques, along different frequencies, aiming to resolve and investigate jets, outflows, as well as compact and innermost regions of asymmetric planetary nebulae (PNe) and objects in transition to PN. All the information gathered allow us to explore the kinematics and other important properties of the structures that play a crucial role in the shaping of complex PNe morphologies, in particular, we explore the role of disks/tori as collimating engine of extreme axisymmetric PNe.
Temperature effects on the infrared spectrum of molecules in planetary nebulae
Authors: Chen Tao , Mackie Cameron , Tielens Alexander G. G. M.
Published: August 2017

In this work, we utilize a method based on Wang-Landau Monte Carlo sampling for studying the temperature effects of astrophysically relavant molecules. Anharmonic effects, e.g., resonances, overtones, and combination bands, are fully incoportated in this method. The calculated infrared (IR) spectra are consistent with the experimental data measured by National Institute of Standards and Technology (NIST).
Characterizing global expansion evolution of the ionized matter in planetary nebulae
Authors: López J. A. , Richer M. G. , Pereyra M. , García-Díaz M. T.
Published: August 2017

Bulk outflow or global expansion velocities are presented for a large number of planetary nebulae (PNe) that span a wide range of evolutionary stages and different stellar populations. The sample comprises 133 PNe from the Galactic bulge, 100 mature and highly evolved PNe from the disk, 11 PNe from the Galactic halo and 15 PNe with very low central star masses and low metallicities, for a total of 259 PNe. These results reveal from a statistical perspective the kinematic evolution of the expansion velocities of PNe in relation to changing characteristics of the central star’s wind and ionizing luminosity and as a function of the evolutionary rate determined by the central (CS) mass. The large number of PNe utilized in this work for each group of PNe under study and the homogeneity of the data provide for the first time a solid benchmark form observations for model predictions, as has been described by López et al. (2016).
Search for binary central stars of the Magellanic Clouds PNe
Authors: Gładkowski Marcin , Hajduk Marcin , Soszyński Igor
Published: August 2017

The Optical Gravitational Experiment (OGLE) was effectively used in discovering binary central stars of planetary nebulae (CSPNe). About 50 binary CSPNe have been hitherto identified in the Galaxy, almost half of them were detected in the OGLE database. We used the OGLE data to search for binary CSPNe in the Magellanic Clouds. We also searched for PNe mimics and removed them from the PNe sample. Here, we present results of the photometric analysis for Small Magellanic Cloud (SMC) and our progress on search of binary central stars in the Large Magellanic Cloud (LMC). So far, we have discovered one binary central star of the PN beyond the Milky Way, which is located in the Small Magellanic Cloud.
Emission Lines of Northern Planetary Nebulae
Authors: Aksaker Nazim , Yerli Sinan K. , Kızıloğlu Ümit , Atalay Betül
Published: August 2017

In this work, we present results of long slit spectrophotometric emission line flux observations of selected planetary nebulae (PNe). We have measured absolute fluxes and equivalent widths (EW) of all observable emission lines. In addition to these observations, electron temperatures (Te), densities (Ne), and chemical abundances were also calculated. The main purpose of this work is to fill the gaps in emission line flux standards for the northern hemisphere. It is expected that the measured fluxes would be used as standard data set for further photometric and spectrometric measurements of HII regions, supernova remnants etc.
Post-AGB binaries as tracers of stellar evolution.
Authors: Van Winckel Hans
Published: August 2017

In this contribution the focus is on post-AGB binaries. It is now well established that these are often surrounded by stable long-lived circumbinary discs of gas and dust. Here we introduce our monitoring programme with our high-resolution spectrograph HERMES mounted on the 1.2m Mercator telescope. We illustrate the use of time-series high-resolution spectra and show that jets observed in many systems are launched at the location of the companion. The jet is likely originating from a circum-companion accretion disc. The link of these systems to some PNe relies on the detection of similar orbits and hence wide spectroscopic orbits among central stars of PNe. The conclusion is that Keplerian discs as well as circum-companion discs are fundamental to understanding the properties and evolution of these interacting evolved binaries.
Efficient design of axially corrugated coaxial-type multi-band horns for reflector antennas
Authors: Zhang Pengyu , Qi Jiaran , Qiu Jinghui
Published: August 2017

A highly efficient design procedure for dielectric-loading multi-band coaxial-type feed antennas is proposed in this paper. Cylindrical modal matching method is employed for generalized scattering matrix calculation inside the feed, while spherical wave expansion is adopted for the feed aperture discontinuity in consideration of the outer shape. Closed-form scattering matrices with respect to different junctions help realize higher computational efficiency than the full-wave simulation solvers, and thus enable rapid optimization in terms of various electrical functional requirements across multiple frequency bands simultaneously. A Ku/Ka multi-band feed is investigated as a numerical example. Excellent radiation performances, including the low cross-polarization level, constant beamwidth, stable phase center, high return loss, and high isolation between bands of interest are achieved by employing multi-scalar rings, dielectric loading, and a three-port hybrid junction. The design is validated by experimental results from a manufactured prototype. Good consistency confirms the accuracy of our numerical approach, and demonstrates the proposed feed a good candidate for Ku/Ka-band satellite communication antenna systems.
Beyond the dyad: making Developmental Origins of Health and Disease (DOHaD) interventions more inclusive
Authors: Pentecost M. , Ross F. C. , Macnab A.
Published: August 2017

Pregnant women, children under 2 and the first thousand days of life have been principal targets for Developmental Origins of Health and Disease interventions. This paradigm has been criticized for laying responsibility for health outcomes on pregnant women and mothers and through the thousand days focus inadvertently deflecting attention from other windows for intervention. Drawing on insights from the South African context, this commentary argues for integrated and inclusive interventions that encompass broader social framings. First, future interventions should include a wider range of actors. Second, broader action frameworks should encompass life-course approaches that identify multiple windows of opportunity for intervention. Using two examples – the inclusion of men, and engagement with adolescents – this commentary offers strategies for producing more inclusive interventions by using a broader social framework.
Laser-assisted transprosthesial coil embolization combined with thrombin injection for treatment of an endoleak type II after endovascular aneurysm repair
Authors: Boehme Tanja , Rastan Aljoscha , Noory Elias , Fluegel Peter-Christian , Zeller Thomas
Published: August 2017

Abstract. The treatment of endoleaks type II had to be adapted to the anatomy of each individual patient. The laser-assisted perforation of the prosthesis can be an easier method to reach the aneurysm sac directly than using transarterial or translumbar approaches.