bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Validation and Study of Particulate Flow in Cyclone Separator using Commercial Computational Fluid Dynamics Code
Authors: Mutha Mayuresh , Katkamwar Vineet , Thirunavukkarasu Bageerathan , Thundil Karuppa Raj R , Sivamurugan P
Published: October 2019

The cyclone separator is widely used for particle separation in industries because of ease in manufacturing and maintenance free working capability. It has also been an automobile component used in air intake system. It’s necessary to understand the flow of air and particles inside the cyclone separator for the design of cyclone separator. Its performance depends upon operational and geometrical parameters. This study is focused on geometric parameter in which a numerical simulation has been carried out to understand the effect of air and particle flow on varying the cone height of cyclone separator using ANSYS 15.0. The analysis involves determining pressure drop at different inlet velocity with corresponding change in cone height of the cyclone separator. The results were obtained for different velocity condition with maximum of 8% of error. Moreover, collection efficiency for cyclone separator was also determined by varying particle size from 0.01 to 10 micron. Decreasing cyclone height led to increase in tangential velocity thus increasing the cyclone efficiency.
Heliotropism of solar PV using the 4-bar mechanism analysis
Authors: Desai Anuj Bimal , Natarajan Sendhil Kumar
Published: October 2019

Solar energy is the most abundant source of renewable energy upon which most conversions of energies could be possible. Solar tracking can be one method through which the energy reception could be increased. Heliotropism is a phenomenon that is observed in various botanical species like leaves, flowers, stems, etc, where there is reaction observed by various parts of the plant corresponding to a solar stimulus. The classic example of this phenomenon is the sunflower effect wherein the sunflower tends to orient itself towards the sun all throughout the day and receives maximum energy at its surface. Similarly, such an effect can be produced using the conventional four bar mechanism which would toggle around the spectrum of the sunlight received to at various positions at various durations of the day. This format of receiving energy would not only increase the quanta of packets being received on an average throughout the day but would also not waste the energy falling on the earth’s surface due to the misalignment of Photovoltaic (PV) cells usually installed in just one direction.
Techno-economic analysis of solar trigeneration system
Authors: Anand B , Murugavelh S
Published: October 2019

In this work, a techno-economic analysis of concentrated photovoltaic/thermal collector (CPVT) driven desalination and cooling plant is presented. The system comprises of a CPVT collector, a humidification-dehumidification (HDH) desalination unit and vapour compression refrigeration (VCR) unit. The CPVT collector having 10 m2 aperture area and a triple junction PV panel placed at the receiver supplies required hot water to the HDH desalination system. Chilled water generated from 0.5 hp compressor operated VCR unit is supplied to the dehumidifier of HDH desalination. The process of cooling and dehumidification using chilled water result in increased desalination yield and resulting air is suitable for air conditioning purpose. The work is aimed to evaluate the annual performance of the trigeneration plant and to estimate the unit cost of fresh water and payback period. The annual performance of the plant is evaluated for the typical metrological year data for the location of Vellore, India. Results show that the annual desalination, electricity and cooling output are 4.2 m3/yr and 3.46 MWh/yr and 0.788 MWh/yr respectively. The daily average desalination and cooling output are 11.12 L/day and 2.47 kWh/day respectively. The annual electricity consumption of the solar cogeneration plant is 6570 kWh/yr. The estimated unit cost of fresh water is ¹10/L. By considering the interest rate of 9 % and total life time of the plant as 20 years, the payback period is estimated to be 6.5 years.
A Numerical Study of fluid flow and Pressure Drop analysis of Catalytic Converter using Commercial CFD code
Authors: Patil Aniket , Takale Mayuresh , Thirunavukkarasu Bageerathan , Thundil Karuppa Raj R
Published: October 2019

In recent years catalytic converter is a necessary device to achieve low emissions in all the vehicles. This study of the after treatment device is to understand the fluid flow and to optimize the design. It is important to know the pressure drop taking place inside the catalytic converter in order to design the catalytic converter. In this paper, a numerical study has been conducted to study the effect of fluid flow inside the catalytic converter and effect of change in geometry using commercial CFD tool. The working fluid considered in this study is air. A 3D simulation is carried out having straight inlet pipe and with change in inlet pipe angle of the catalytic converter. The monolith substrate region is modeled as a porous medium. The governing equations namely conservation of mass, momentum are used for solving the analysis. The analysis involved determining pressure variation across the geometry of the converter system for different mass flow rates and change inlet pipe angle. The numerical results were used determine the pressure drop across the substrate and the flow characteristics inside the catalytic converter. The numerical study shows good conformance with the experimental results with maximum deviation of error 2.54% for straight inlet pipe configuration. The effect of change in inlet pipe angle, effect of inlet cone angle and effect of splitting the substrate into sections are also presented.
A Review on Computational Fluid Dynamics Analysis on Greenhouse Dryer
Authors: Natarajan Sendhil Kumar , Elavarasan E
Published: October 2019

Over the decades Solar energy has been utilizing for the conservation of various agricultural products at different zones in the world. Existing literature reveals that open dehydrating is the mostly followed for the desired application and its efficiency limited to certain extent. In order to overcome the limitations, solar dehydrating is proposed and implemented by various researchers. Greenhouse dryer found to be most appropriate technique to preserve different kinds of fruits, vegetables and grain products. In recent years, a great deal of research has been focused to enhance the performance of the selected method. Traditionally it is confined to empirical form and later it is extended to CFD analysis to obtain effective results through simulations. The present article presents the extensive survey over empirical and CFD analysis of Green house dryer application on dehydrating in both active and passive mode of convections.
Organizational Level Cloud Diagnostics System of Complex Electromechanical System Based on SOA
Authors: Cai Deyong , Zhao Yingying , Deng Jing , Zhang Dongchen
Published: October 2019

In order to better solve the problem of insufficient support ability of high-tech electromechanical system, the cloud computing model was introduced into fault diagnostics system of electromechanical system. An open, loose-coupled architecture of Integrated Diagnostic System (IDS) for electromechanical system is put forward basing on Service- Oriented Cloud Computing Architecture (SOCCA). Test and diagnosis resources of repair shop at all levels and total life cycle information resources of electromechanical system were integrated by Portable Maintenance Aid (PMA) with cloud diagnostics platform. According to different demands, Test and diagnosis resources can be divided into data, software, platform and infrastructure, which can be provided on demand to maintainer of all levels as a service. This allows more complex maintenance issues to be accomplished at Forward Operating Locations (FOLs) by better utilizing the most relevant diagnostic information to enable direct, real-time, and engineering assistance when needed. Organizational Level (O-Level) IDS can effectively improve O-level maintainer support ability of complex electromechanical system.
Design of Answer-Grabbing Devices Based on Labview
Authors: Zhao Yang , Rui Wu , Youjia Wang , Yuan Li
Published: October 2019

Answer-grabbing devices are widely used in various TV programs, competitions and other fields. At present, with the increasing demand for fairness in competition, higher requirements have been put forward for answer-grabbing devices, such as higher sensitivity, better reliability, more powerful functions and so on. To meet this requirement, this paper designs a answer-grabbing devices based on Labview, which consists of answer-grabbing module, display module, compere button module and control module. Through design of front panel and program, debugging and operation, the functions of answer-grabbing device, as timing, scoring and zero clearing are finally realized. Experiments show that the system has high reliability, sensitivity and multiple functions.
Two-dimensional Aerodynamic Loads of Thermal Protection System Considering Different Widths of the Strain Isolation Pad
Authors: Feng Yupeng , Cheng Jialin , Li Tao , Chen Bin
Published: October 2019

Thermal Protection System (TPS) is widely adopted to prevent aircraft substructure from the high environment temperature which is assembled by the ceramic tile, the strain isolation pad (SIP) and the substrate structure. The surface of shuttle is covered by individual ceramic tiles which are bonded to the substrate. The structure of SIP is the significant component of TPS which has important influence on the aerodynamic loads of TPS. To reveal the effect of the width of SIP on the aerodynamic loads, the two-dimensional TPS models considering various widths of SIP, 0.5mm, 0.7mm, 1.0mm, 1.3mm and 1.5mm, are founded and are simulated by computational fluid dynamic (CFD) method. The models are established by combining SIP and the ceramic tile on the surface of NACA0012. The flow around TPS, including flow around NACA0012 and internal flow, is simulated by solving Navier-Stokes (N-S) equation and Spalart-Allmaras (S-A) model. The pressure distributions around TPS are obtained and numerical results show: (1) In X and Y direction, with the width of SIP, △w, being 1.0mm, the forces are minimum, 159.9N in X-direction and 313.3N in Y-direction, respectively; (2) The different force of tile-II is related to both the pressure distribution and the flow speed around tile-II.
Simulation of Stress Distribution and Deformation Analysis for Cantilever I-beams Using ABAQUS Software
Authors: Runsheng Wen , Yang Zhang
Published: October 2019

In this paper, the stress distribution of the I-beam cantilever beam is simulated by ABAQUS software, and the uniform load increases with time on the surface of the I-beam to observe the position of the maximum stress and the deformation of the right end.
Experimental Study of Acoustically Enhanced Heat-Transfer from Copper Sphere in a Steady Flow Field
Authors: Weilong Xu , Genshan Jiang , Weicai Peng , Xuesong He
Published: October 2019

The combined effects of acoustic field and flow field on the forced convective heat transfer rate during cooling of a stationary sphere were investigated experimentally. The acoustic frequency is in the range of 100 to 2500 Hz, with the velocity ratio of acoustic velocity and flow velocity is in the range of 0.59 to 4.76. The relationship among sound pressure levels, frequency, flow velocity and the diameter of the sphere with the temperature gradient of the sphere were analyzed. The results show that higher velocity ratio cause higher heat-transfer rate. However, when the sphere size is 5 mm, the heat transfer rate is always lower than that without an acoustic field during our experiment, and when the sphere size is 10 mm and the velocity ratio is higher than 3.38, the heat transfer rate is higher than that without an acoustic field, but when the size of the copper sphere is 15 mm, the velocity ratio is decreased to 1.89. There is a special frequency, at which Nu reaches a maximum. This special frequency increases with increasing SPLs. The conclusions highlight a good application prospect in combustion for the boiler.
Analysis Line Approach for Assembly Tolerance Analysis
Authors: Peng Heping , Peng Zhuoqun
Published: October 2019

This work presents the analysis line approach for assembly tolerance analysis. Firstly, the product functional requirements and geometric variations of part positioning features can be converted into small displacements of a series of analysis points along the specified analysis directions. The small displacement torsor (SDT) theory is employed to establish the mathematical relations between the displacements of these analysis points. And then, the variation transfer relations and tolerance accumulation calculations of various orthogonal joints between different parts are studied to determine the maximum displacement of the analysis points on the functional surface. The final displacement accumulation results of the functional surface are compared with the geometric functional requirements of the product, so as to judge whether the product functional requirements are met. Finally, an example is given to demonstrate the effectiveness of the proposed analysis line approach.
Experimental research of nonlinear damage diagnosis using ARMA/GARCH method
Authors: Guo Huiyong , Zhou Rong
Published: October 2019

Nonlinear damage such as fatigue crack often occurs in some engineering structures, which brings challenges in structural damage diagnosis. A nonlinear damage diagnosis method based on ARMA/GARCH model is proposed to extract the nonlinear characteristic caused by cracks. First, the background description of ARMA/GARCH model is given and a damage diagnosis index based on this model is proposed to detect nonlinear damage location. The main advantage of ARMA/GARCH model is that this hybrid model can well simulate structural time domain acceleration response and effectively extract the nonlinear damage feature. An experiment of three-storey frame structure, which utilized a mechanism constituted of a bumper and a center column to model breathing crack, is studied. The results show that the damage diagnosis index based on ARMA/GARCH model exhibits good accuracy.
Echo chambers in climate science
Authors: Jasny Lorien , Fisher Dana R
Published: October 2019

To date, echo chambers in American climate politics have been found to focus on the climate-related policy instrument that is under review. In this paper, we explore how echo chambers change over time, integrating data collected on the federal climate policy network after the first 100 days of the Trump Administration had passed with data collected during two periods during the Obama Administration. We employ Exponential Random Graph (ERG) models to test for the similarity and differences over time in the top policy actors working on the issue during each time period. We then compare the newer findings from 2017 to previous work on data from 2010 and 2016. We find that echo chambers continue to play a significant role in the network of information exchange among policy elites and in the adoption of new information sources over time. In contrast to previous findings, however, where echo chambers centered on specific policy instruments—a binding international commitment to emission reductions or the Obama Administration’s Clean Power Plan—opinion regarding whether or not climate change is caused by humans (i.e. is anthropogenic) has become the central organizing force behind echo chambers in the US climate policy network. These results provide new empirical evidence that ideological polarization drives the selection of expert information in the debate around climate politics. Moreover, our results show how misinformation diffuses among political elites working on the issue of climate change.
Point defects, compositional fluctuations, and secondary phases in non-stoichiometric kesterites
Authors: Schorr Susan , Gurieva Galina , Guc Maxim , Dimitrievska Mirjana , Pérez-Rodríguez Alejandro , Izquierdo-Roca Victor , Schnohr Claudia S , Kim Juran , Jo William , Merino José Manuel
Published: October 2019

The efficiency of kesterite-based solar cells is limited by various non-ideal recombination paths, amongst others by a high density of defect states and by the presence of binary or ternary secondary phases within the absorber layer. Pronounced compositional variations and secondary phase segregation are indeed typical features of non-stoichiometric kesterite materials. Certainly kesterite-based thin film solar cells with an off-stoichiometric absorber layer composition, especially Cu-poor/Zn-rich, achieved the highest efficiencies, but deviations from the stoichiometric composition lead to the formation of intrinsic point defects (vacancies, anti-sites, and interstitials) in the kesterite-type material. In addition, a non-stoichiometric composition is usually associated with the formation of an undesirable side phase (secondary phases). Thus the correlation between off-stoichiometry and intrinsic point defects as well as the identification and quantification of secondary phases and compositional fluctuations in non-stoichiometric kesterite materials is of great importance for the understanding and rational design of solar cell devices. This paper summarizes the latest achievements in the investigation of identification and quantification of intrinsic point defects, compositional fluctuations, and secondary phases in non-stoichiometric kesterite-type materials.
Geometry of Bäcklund transformations I: generality
Authors: Hu Yuhao
Published: October 2019

Using Élie Cartan’s method of equivalence, we prove an upper bound for the generality of generic rank-1 Bäcklund transformations relating two hyperbolic Monge-Ampère systems. In cases when the Bäcklund transformation admits a symmetry group whose orbits have codimension 1, 2, or 3, we obtain classification results and new examples of auto-Bäcklund transformations.
Wall-crossing and recursion formulae for tropical Jucys covers
Authors: Hahn Marvin , Lewański Danilo
Published: October 2019

Hurwitz numbers enumerate branched genus

g
g

covers of the Riemann sphere with fixed ramification data or equivalently certain factorisations of permutations. Double Hurwitz numbers are an important class of Hurwitz numbers, obtained by considering ramification data with a specific structure. They exhibit many fascinating properties, such as a beautiful piecewise polynomial structure, which has been well-studied in the last 15 years. In particular, using methods from tropical geometry, it was possible to derive wall-crossing formulae for double Hurwitz numbers in arbitrary genus. Further, double Hurwitz numbers satisfy an explicit recursive formula. In recent years several related enumerations have appeared in the literature. In this work, we focus on two of those invariants, so-called monotone and strictly monotone double Hurwitz numbers. Monotone double Hurwitz numbers originate from random matrix theory, as they appear as the coefficients in the asymptotic expansion of the famous Harish-Chandra–Itzykson–Zuber integral. Strictly monotone double Hurwitz numbers are known to be equivalent to an enumeration of Grothendieck dessins d’enfants. These new invariants share many structural properties with double Hurwitz numbers, such as piecewise polynomiality. In this work, we enlarge upon this study and derive new explicit wall-crossing and recursive formulae for monotone and strictly monotone double Hurwitz numbers. The key ingredient is a new interpretation of monotone and strictly monotone double Hurwitz numbers in terms of tropical covers, which was recently derived by the authors. An interesting observation is the fact that monotone and strictly monotone double Hurwitz numbers satisfy wall-crossing formulae, which are almost identical to the classical double Hurwitz numbers.
The Distinctive Character of Musical Experience
Authors: Peacocke Christopher
Published: October 2019

The goal of this paper is to use the dual resources of the contemporary theory of intentional content and the notion of experiencing something metaphorically as something else, which I have defended in my earlier work, to explain the distinctive character of musical experience. These resources are used to explain Felix Mendelssohn’s point that emotional content in music can be more specific than anything capturable in language; to give an account of the role of metaphor in musical experience that does not generate insoluble puzzles; to formulate a Principle of Acquaintance for the content of musical experience; to give a theory of intentional subjects or ‘personae’ in music, and their significance; to explain two ways of hearing action in music; and to elaborate the significance for musical experience of the fact that perception of music is perception of agency.
CRISPR-Cas9 genome editing for cancer immunotherapy: opportunities and challenges
Authors: Chen Ming , Xu Jiang , Zhou Yang , Zhang Silin , Zhu Di
Published: October 2019

Cancer immunotherapy, consisting of antibodies, adoptive T-cell transfer, vaccines and cytokines, is a novel strategy for fighting cancer by artificially stimulating the immune system. It has developed rapidly in recent years, and its efficacy in hematological malignancies and solid tumors has been remarkable. It is regarded as one of the most promising methods for cancer therapy. The current trend in immunotherapy research seeks to improve its efficacy and to ensure the safety of cancer immunotherapy through the use of gene editing technologies. As it is an efficient and simple technology, the CRISPR-Cas9 system is highly anticipated to dramatically strengthen cancer immunotherapy. Intensive research on the CRISPR-Cas9 system has provided increasing confidence to clinicians that this system can be put into clinical use in the near future. This paper reviews the application and challenges of CRISPR-Cas9 in this field, based on various strategies including adaptive cell therapy and antibody therapy, and also highlights the function of CRISPR/Cas9 in the screening of new cancer targets.
Implementation And Evaluation Of The mCityPASS Protocol For Secure And Private Access To Associated Touristic Services
Authors: Payeras-Capella M Magdalena , Mut-Puigserver Macia , Conejero-Alberola Pau , Castella-Roca Jordi , Huguet-Rotger Llorenç
Published: October 2019

Touristic City Cards are managed by some city councils in order to make a step toward the SmartCity concept. Touristic City Cards enable the integration of different touristic services so as to facilitate the access to transport, cultural sites and touristic attractions to visitors. In this paper, we introduce a secure mobile system called mCityPASS that allows the smart management and secure access to this kind of service. We have implemented the system in a smartphone platform in such a way that the mobile device contains the purchased access element that holds a set of e-tickets that enables the visitors of a city to make use of the specified touristic services. The paper presents the details of the whole implementation of the system and an evaluation of the performance and the effectiveness of it. Also, an analysis of the privacy and the security properties of the presented scheme has been conducted. As a result, we can assure that the system preserves the privacy of the tourists and fulfills the more challenging security properties: fairness, non-overspending, exculpability, unsplittability and selective reusability.
The role of 99mTc-HMPAO-labelled white blood cell scintigraphy in the diagnosis of cardiac device-related infective endocarditis
Authors: Holcman Katarzyna , Małecka Barbara , Rubiś Paweł , Ząbek Andrzej , Szot Wojciech , Boczar Krzysztof , Leśniak-Sobelga Agata , Hlawaty Marta , Wiśniowska-Śmiałek Sylwia , Stępień Agnieszka , Podolec Piotr , Kostkiewicz Magdalena
Published: October 2019

Aims

The hybrid technique of single-photon emission tomography and computed tomography with technetium99m-hexamethylpropyleneamine oxime–labelled leucocytes (99mTc-HMPAO-SPECT/CT) is an emerging diagnostic technique in patients with cardiac device-related infective endocarditis (CDRIE). This prospective study assessed the 99mTc-HMPAO-SPECT/CT diagnostic profile and its added value to the modified Duke criteria (mDuke) in CDRIE diagnostic work-up.

Methods and results

The study examined 103 consecutive patients with suspected CDRIE, who underwent 99mTc-HMPAO-SPECT/CT. Diagnostic accuracy was calculated based on a final clinical CDRIE diagnosis, including microbiology, echocardiography, and a 6-month follow-up. Subsequently, we compared the diagnostic value of the initial mDuke classification with a classification including 99mTc-HMPAO-SPECT/CT positive results as an additional major CDRIE criterion: mDuke-SPECT/CT.

Overall, CDRIE was diagnosed in 31 (31%) patients, whereas 35 (34%) 99mTc-HMPAO-SPECT/CT were positive. 99mTc-HMPAO-SPECT/CT was characterized by 86% accuracy, 0.69 Cohen’s kappa coefficient, 84% sensitivity, 88% specificity, 93% negative, and 74% positive predictive values. The original mDuke displayed 83% accuracy, 0.52 kappa, whereas mDuke-SPECT/CT had 88% accuracy, and 0.73 kappa. Compared with mDuke, mDuke-SPECT/CT showed significantly higher sensitivity (87% vs. 48%, P < 0.001). According to mDuke, 49.5% of patients had possible CDRIE, and after reclassification, that figure dropped to 37%. Furthermore, having assessed the diagnosis categorization improvement following the incorporation of 99mTc-HMPAO-SPECT/CT, the net reclassification index value was found to be 31.4%.

Conclusion

In patients with CDRIE, 99mTc-HMPAO-SPECT/CT provides high diagnostic accuracy, whereas a negative scan excludes CDRIE with high probability. Inclusion of 99mTc-HMPAO-SPECT/CT into mDuke diagnostic criteria yields significantly higher sensitivity and a reduction in possible CDRIE diagnoses.
Impact of reduced-dose prasugrel vs. standard-dose clopidogrel on in-hospital outcomes of percutaneous coronary intervention in 62 737 patients with acute coronary syndromes: a nationwide registry study in Japan
Authors: Akita Keitaro , Inohara Taku , Yamaji Kyohei , Kohsaka Shun , Numasawa Yohei , Ishii Hideki , Amano Tetsuya , Kadota Kazushige , Nakamura Masato , Maekawa Yuichiro
Published: October 2019

Aims 

In Japan, reduced-dose prasugrel (loading/maintenance dose, 20/3.75 mg) has been approved for use in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI), because of the higher bleeding risk among East Asians. However, its safety in the real-world population has not been investigated. We aimed to evaluate the effectiveness and safety of reduced-dose prasugrel vs. standard-dose clopidogrel in ACS patients undergoing PCI.

Methods and results 

Acute coronary syndrome patients who underwent PCI in 2016, who were treated with either reduced-dose prasugrel or standard-dose clopidogrel in addition to aspirin, were identified from the nationwide Japanese PCI registry. The primary outcome was in-hospital mortality following PCI. Secondary outcomes included stent thrombosis and bleeding complication after PCI. Among 62 737 ACS patients who underwent PCI at any of 986 participating centres across Japan (clopidogrel 31.9%; prasugrel 68.1%), we identified 12 016 propensity score-matched pairs (24 032 patients; age 69.4 ± 12.2 years; female 24.9%; ST-elevation myocardial infarction 42.3%). Compared with standard-dose clopidogrel, reduced-dose prasugrel was associated with increased risk of bleeding [odds ratio (OR) 1.65, 95% confidence interval (CI) 1.10–2.51; P = 0.016], but both had similar rates of mortality (OR 1.11, 95% CI 0.89–1.38; P = 0.371) and stent thrombosis (OR 1.29, 95% CI 0.73–2.30; P = 0.387) as well as similar falsification endpoints of cardiac tamponade and emergent operation.

Conclusion 

In Japanese ACS patients undergoing PCI, the risk of bleeding is higher when using reduced-dose prasugrel than when using standard-dose clopidogrel, but there is no significant difference in in-hospital mortality and incidence of stent thrombosis between the two antiplatelet regimens.
Maternal health after Ebola: unmet needs and barriers to healthcare in rural Sierra Leone
Authors: Elston James W T , Danis Kostas , Gray Nell , West Kim , Lokuge Kamalini , Black Benjamin , Stringer Beverley , Jimmisa Augustine S , Biankoe Aiah , Sanko Mohammed O , Kazungu Donald S , Sang Sibylle , Loof Annemarie , Stephan Claudia , Caleo Grazia
Published: October 2019

Sierra Leone has the world’s highest estimated maternal mortality. Following the 2014–16 Ebola outbreak, we described health outcomes and health-seeking behaviour amongst pregnant women to inform health policy. In October 2016–January 2017, we conducted a sequential mixed-methods study in urban and rural areas of Tonkolili District comprising: household survey targeting women who had given birth since onset of the Ebola outbreak; structured interviews at rural sites investigating maternal deaths and reporting; and in-depth interviews (IDIs) targeting mothers, community leaders and health workers. We selected 30 clusters in each area: by random GPS points (urban) and by random village selection stratified by population size (rural). We collected data on health-seeking behaviours, barriers to healthcare, childbirth and outcomes using structured questionnaires. IDIs exploring topics identified through the survey were conducted with a purposive sample and analysed thematically. We surveyed 608 women and conducted 29 structured and 72 IDIs. Barriers, including costs of healthcare and physical inaccessibility of healthcare facilities, delayed or prevented 90% [95% confidence interval (CI): 80–95] (rural) vs 59% (95% CI: 48–68) (urban) pregnant women from receiving healthcare. Despite a general preference for biomedical care, 48% of rural and 31% of urban women gave birth outside of a health facility; of those, just 4% and 34%, respectively received skilled assistance. Women expressed mistrust of healthcare workers (HCWs) primarily due to payment demanded for ‘free’ healthcare. HCWs described lack of pay and poor conditions precluding provision of quality care. Twenty percent of women reported labour complications. Twenty-eight percent of villages had materials to record maternal deaths. Pregnant women faced important barriers to care, particularly in rural areas, leading to high preventable mortality and morbidity. Women wanted to access healthcare, but services available were often costly, unreachable and poor quality. We recommend urgent interventions, including health promotion, free healthcare access and strengthening rural services to address barriers to maternal healthcare.
Effect of Stopping Cotrimoxazole Preventive Therapy on Microbial Translocation and Inflammatory Markers Among Human Immunodeficiency Virus–Infected Ugandan Adults on Antiretroviral Therapy: The COSTOP Trial Immunology Substudy
Authors: Kyosiimire-Lugemwa Jacqueline , Anywaine Zacchaeus , Abaasa Andrew , Levin Jonathan , Gombe Ben , Musinguzi Kenneth , Kaleebu Pontiano , Grosskurth Heiner , Munderi Paula , Pala Pietro
Published: October 2019

Background

Cotrimoxazole preventive therapy (CPT) in human immunodeficiency virus (HIV) infection is a World Health Organization–recommended standard of care in resource-limited settings, but the mechanism of CPT’s beneficial effects is unclear. The COSTOP trial (ISRCTN44723643) evaluated the noninferiority of discontinuing CPT in stabilized patients on antiretroviral therapy. The COSTOP immunology substudy was conducted on a subset of COSTOP participants randomized to continue CPT (n = 86) or discontinue CPT (placebo, n = 86) as daily treatment for 1 year.

Methods

We evaluated whether CPT reduces microbial translocation, indicated by the presence of bacterial lipopolysaccharide (LPS) and LPS control factors such as soluble CD14 (sCD14) and endotoxin core antibody (EndoCAb immunoglobulin M [IgM]) in plasma. Intestinal barrier damage as indicated by plasma intestinal fatty acid binding protein (IFABP), T-cell activation, and the inflammatory markers C-reactive protein (CRP), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α) were also evaluated.

Results

We found no significant change in markers of microbial translocation (LPS, IFABP, sCD14, and T-cell activation), with decreased EndoCAb IgM. There was significant increase in inflammation markers (CRP and IL-6) after stopping CPT compared to those who continued CPT.

Conclusions

These results add to the evidence of immunological benefits of CPT among HIV-infected populations in resource-limited settings. However, no evidence of reducing microbial translocation was observed.
Consolidation of Usability Problems With Novice Evaluators Re-Examined in Individual vs. Collaborative Settings
Authors: Hoffmann Rebekka , Jónsdóttir Anna Helga , Hvannberg Ebba Thora
Published: October 2019

Usability testing can involve multiple users and evaluators. In such cases, consolidating usability problems (UPs) constitutes an essential part of data analysis. In a between-subjects design, this study aims to re-examine a previous study by comparing the results of novice evaluators merging UPs individually vs. collaboratively and to assess the quality of the final UP lists, by computing the merging rate and the accuracy rate, respectively. Law and Hvannberg compared the results of evaluators merging UPs individually vs. collaboratively in a within-subjects design, revealing a tendency towards merging UPs in collaborative settings. In the present study, 45 novice evaluators consolidated four UP lists into a single UP master list while working alone or with a partner. The results showed no significant difference between evaluators in the two settings, suggesting that the UP consolidation process does not benefit from positive group decision effects.
Keeping Armed Actors Out: The Protective Effect of Shuras in Afghanistan
Authors: Breslawski Jori
Published: October 2019

Though civilians have traditionally been perceived as powerless at the hands of armed groups in civil war, recent research credits civilians with a greater degree of agency than previously perceived, revealing that effective institutions may be able to lessen the likelihood of violence in their locality through strategies such as resolving disputes between community members before they involve armed actors. However, systematic tests have been restricted in their scope and level of analysis due to the limited availability of data that captures the effectiveness of community-level institutions, so the applications of existing findings remain unclear. In this article, I replicate findings that effective local institutions lessen the likelihood of violence, even in a “hard” test of the hypothesis. Drawing upon survey data from Afghanistan, I demonstrate that more effective shuras and jirgas are associated with communities that perceive themselves and their families as safer, even in areas marred by armed group violence.
Patient-Reported and Parent Proxy-Reported Outcomes in Pediatric Medical Specialty Clinical Settings: A Systematic Review of Implementation
Authors: Anderson Lindsay M , Papadakis Jaclyn L , Vesco Anthony T , Shapiro Jenna B , Feldman Marissa A , Evans Meredyth A , Weissberg-Benchell Jill
Published: October 2019

Objective

Youth with chronic illness are at higher risk for psychosocial difficulties, leading to a call for screening via patient-reported outcomes (PROs). The purpose of the current review is to summarize PRO implementation in pediatric medical specialty settings. A literature review of PRO implementation in these settings, conceptual issues, value and approach, legal and ethical concerns, as well as a case example of PROA in type 1 diabetes are presented.

Methods

A systematic review was conducted to identify relevant articles published since the most recent Journal of Pediatric Psychology Special Issue on Evidence-Based Assessment in Pediatric Psychology (2008).

Results

Thirty-two articles were identified and reviewed. The majority of studies reported that PROA was feasible, did not disrupt clinic flow, identified psychosocial issues warranting intervention, and was acceptable to families and providers. Response to elevated scores and impact on behavioral health referrals varied.

Conclusion

While many evidenced-based assessment measures are well-validated within pediatric chronic illness groups, the literature regarding implementation of PROs is still emerging. Research findings are promising, with PROs being feasible, acceptable, and leading to increased discussion of psychosocial issues when integrated into pediatric medical settings. Additional research is needed to evaluate the longitudinal impact of PROs and the optimal manner of responding to assessment data, particularly when clinically-elevated. Ultimately, identifying psychosocial issues in pediatric medical settings can promote optimal health and well-being of youth with chronic illness and their families.
The Relationship Between Interviewer-Respondent Rapport and Data Quality
Authors: Sun Hanyu , Conrad Frederick G , Kreuter Frauke
Published: October 2019

Interviewer-respondent rapport is generally considered to be beneficial for the quality of the data collected in survey interviews; however, the relationship between rapport and data quality has rarely been directly investigated. We conducted a laboratory experiment in which eight professional interviewers interviewed 125 respondents to see how the rapport between interviewers and respondents is associated with the quality of data—primarily disclosure of sensitive information—collected in these interviews. It is possible that increased rapport between interviewers and respondents might motivate respondents to be more conscientious, increasing disclosure; alternatively, increased rapport might inhibit disclosure because presenting oneself unfavorably is more aversive if respondents have a positive relationship with the interviewer. More specifically, we examined three issues: (1) what the relationship is between rapport and the disclosure of information of varying levels of sensitivity, (2) how rapport is associated with item nonresponse, and (3) whether rapport can be similarly established in video-mediated and computer-assisted personal interviews (CAPIs). We found that (1) increased respondents’ sense of rapport increased disclosure for questions that are highly sensitive compared with questions about topics of moderate sensitivity; (2) increased respondents’ sense of rapport is not associated with a higher level of item nonresponse; and (3) there was no significant difference in respondents’ rapport ratings between video-mediated and CAPI, suggesting that rapport is just as well established in video-mediated interviews as it is in CAPI.
Language Proficiency Among Respondents: Implications for Data Quality in a Longitudinal Face-To-Face Survey
Authors: Wenz Alexander , Al Baghal Tarek , Gaia Alessandra
Published: October 2019

When surveying immigrant populations or ethnic minority groups, it is important for survey researchers to consider that respondents might vary in their level of language proficiency. While survey translations might be offered, they are usually available for a limited number of languages, and even then, non-native speakers may not utilize questionnaires translated into their native language. This article examines the impact of language proficiency among respondents interviewed in English on survey data quality. We use data from Understanding Society: The United Kingdom Household Longitudinal Study (UKHLS) to examine five indicators of data quality, including “don’t know” responding, primacy effects, straightlining in grids, nonresponse to a self-completion survey component, and change in response across survey waves. Respondents were asked whether they are native speakers of English; non-native speakers were subsequently asked to self-rate whether they have any difficulties speaking or reading English. Results suggest that non-native speakers provide lower data quality for four of the five quality indicators we examined. We find that non-native respondents have higher nonresponse rates to the self-completion section and are more likely to report change across waves, select the primary response option, and show straightlining response behavior in grids. Furthermore, primacy effects and nonresponse rates to the self-completion section vary by self-rated level of language proficiency. No significant effects were found with regard to “don’t know” responding between native and non-native speakers.
Prediction of galaxy halo masses in SDSS DR7 via a machine learning approach
Authors: Calderon Victor F , Berlind Andreas A
Published: October 2019

We present a machine learning (ML) approach for the prediction of galaxies’ dark matter halo masses which achieves an improved performance over conventional methods. We train three ML algorithms (XGBoost, random forests, and neural network) to predict halo masses using a set of synthetic galaxy catalogues that are built by populating dark matter haloes in N-body simulations with galaxies and that match both the clustering and the joint distributions of properties of galaxies in the Sloan Digital Sky Survey (SDSS). We explore the correlation of different galaxy- and group-related properties with halo mass, and extract the set of nine features that contribute the most to the prediction of halo mass. We find that mass predictions from the ML algorithms are more accurate than those from halo abundance matching (HAM) or dynamical mass estimates (DYN). Since the danger of this approach is that our training data might not accurately represent the real Universe, we explore the effect of testing the model on synthetic catalogues built with different assumptions than the ones used in the training phase. We test a variety of models with different ways of populating dark matter haloes, such as adding velocity bias for satellite galaxies. We determine that, though training and testing on different data can lead to systematic errors in predicted masses, the ML approach still yields substantially better masses than either HAM or DYN. Finally, we apply the trained model to a galaxy and group catalogue from the SDSS DR7 and present the resulting halo masses.
ExoMol molecular line lists – XXXV. A rotation-vibration line list for hot ammonia
Authors: Coles Phillip A , Yurchenko Sergei N , Tennyson Jonathan
Published: October 2019

A new hot line list for 14NH3 is presented. The line list CoYuTe was constructed using an accurate, empirically refined potential energy surface and a CCSD(T)/aug-cc-pVQZ ab initio dipole moment surface of ammonia, previously reported. The line list is an improvement of the ammonia line list BYTe. The CoYuTe line list covers wavenumbers up to 20 000 cm−1, i.e. wavelengths beyond 0.5 μm for temperatures up to 1500 K. Comparisons with the high temperature experimental data from the literature show excellent agreement for wavenumbers below 6000 cm−1. The CoYuTe line list contains 16.9 billion transitions and is available from the ExoMol website (www.exomol.com) and the CDS data base.
Rotational and pulsational variability in the TESS light curve of HD 27463
Authors: Khalack V , Lovekin C , Bowman D M , Kobzar O , David-Uraz A , Paunzen E , Sikora J , Lenz P , Kochukhov O , Holdsworth D L , Wade G A
Published: October 2019

The new photometric data on pulsating Ap star HD 27463 obtained recently with the Transiting Exoplanet Survey Satellite (TESS) are analysed to search for variability. Our analysis shows that HD 27463 exhibits two types of photometric variability. The low-frequency variability with the period P  = 2.834 274 ± 0.000 008 d can be explained in terms of axial stellar rotation assuming the oblique magnetic rotator model and presence of surface abundance/brightness spots, while the detected high-frequency variations are characteristics of δ Scuti pulsations. From the analysis of Balmer line profiles visible in two FEROS spectra of HD 27463 we have derived its effective temperature and surface gravity, finding values that are close to those published for this star in the TESS Input Catalogue (TIC). Knowing the rotation period and the v sin i value estimated from the fitting of Balmer line profiles we found that the rotational axis is inclined to the line of sight with an angle of $i=33\pm 8\deg$. Our best-fitting model of the observed pulsation modes results in an overshoot parameter value fov = 0.014 and values of global stellar parameters that are in good agreement with the data reported in the TIC and with the data derived from fitting Balmer line profiles. This model indicates an age of 5.0 ± 0.4 × 108 yr, which corresponds to a core hydrogen fraction of 0.33.
NuSTAR view of Be/X-ray binary pulsar 2S 1417−624 during 2018 giant outburst
Authors: Gupta Shivangi , Naik Sachindra , Jaisawal Gaurava K
Published: October 2019

We report the results obtained from a detailed timing and spectral studies of Be/X-ray binary pulsar 2S 1417−624 using data from Swift and NuSTAR observatories. The observations were carried out at the peak of a giant outburst of the pulsar in 2018. X-ray pulsations at ∼17.475 s were detected in the source light curves up to 79 keV. The evolution of the pulse profiles with energy was found to be complex. A four-peaked profile at lower energies gradually evolved into a double-peak structure at higher energies. The pulsed fraction of the pulsar, calculated from the NuSTAR observation was found to follow an anticorrelation trend with luminosity as observed during previous giant X-ray outburst studies in 2009. The broad-band spectrum of the pulsar is well described by a composite model consisting of a cut-off power-law model modified with the interstellar absorption, a thermal blackbody component with a temperature of ≈1 keV, and a Gaussian function for the 6.4 keV iron emission line. Though the pulsar was observed at the peak of the giant outburst, there was no signature of presence of any cyclotron line feature in the spectrum. The radius of the blackbody emitting region was estimated to be ≈2 km, suggesting that the most probable site of its origin is the stellar surface of the neutron star. Physical models were also explored to understand the emission geometry of the pulsar and are discussed in the paper.
The Evolutionary History of Ephs and Ephrins: Toward Multicellular Organisms
Authors: Arcas Aida , Wilkinson David G , Nieto M Ángela
Published: October 2019

Eph receptor (Eph) and ephrin signaling regulate fundamental developmental processes through both forward and reverse signaling triggered upon cell–cell contact. In vertebrates, they are both classified into classes A and B, and some representatives have been identified in many metazoan groups, where their expression and functions have been well studied. We have extended previous phylogenetic analyses and examined the presence of Eph and ephrins in the tree of life to determine their origin and evolution. We have found that 1) premetazoan choanoflagellates may already have rudimental Eph/ephrin signaling as they have an Eph-/ephrin-like pair and homologs of downstream-signaling genes; 2) both forward- and reverse-downstream signaling might already occur in Porifera since sponges have most genes involved in these types of signaling; 3) the nonvertebrate metazoan Eph is a type-B receptor that can bind ephrins regardless of their membrane-anchoring structure, glycosylphosphatidylinositol, or transmembrane; 4) Eph/ephrin cross-class binding is specific to Gnathostomata; and 5) kinase-dead Eph receptors can be traced back to Gnathostomata. We conclude that Eph/ephrin signaling is of older origin than previously believed. We also examined the presence of protein domains associated with functional characteristics and the appearance and conservation of downstream-signaling pathways to understand the original and derived functions of Ephs and ephrins. We find that the evolutionary history of these gene families points to an ancestral function in cell–cell interactions that could contribute to the emergence of multicellularity and, in particular, to the required segregation of cell populations.