bluuebunny/crossref_metadata_2025 huggingface dataset:
Hepatitis delta virus infection in a large cohort of chronic hepatitis B patients in Ethiopia
Authors: Aberra Hanna , Gordien Emmanuel , Desalegn Hailemichael , Berhe Nega , Medhin Girmay , Mekasha Bitsatab , Gundersen Svein G. , Gerber Athenaïs , Stene‐Johansen Kathrine , Øverbø Joakim , Johannessen Asgeir
Published: October 2017

Background & Aims

Hepatitis D virus (HDV) infection is associated with a more severe outcome in patients with chronic hepatitis B (CHB); however, little is known about the presence of HDV in sub‐Saharan Africa. We aimed to determine the prevalence of HDV infection, as well as its clinical, biological and virological characteristics, in a large CHB cohort in Ethiopia.

Methods

In total, 1267 HIV‐negative CHB patients at St. Paul's Hospital Millennium Medical College in Addis Ababa were screened for anti‐HDV antibodies using ELISA assays. Confirmed positive samples were further tested for HDV RNA using a consensus commercial real‐time RT‐PCR assay. HDV genotypes were also determined for RNA‐positive samples by nucleotide sequencing followed by phylogenetic analyses. Demographical, clinical and biological data from patients were recorded and compared based on HDV RNA results.

Results

Most patients (n = 748, 59.0%) were men, and the median age was 31 years (interquartile range 26‐40). Anti‐HDV antibodies were detected in 19 individuals (1.5%), 12 of whom were HDV RNA‐positive with a viral load ranging from <2 to >8 log 10 IU/mL. All strains were genotype 1. HDV RNA‐positive patients were more likely to have significant liver fibrosis (63.6% vs 24.7%, P = .007) and cirrhosis (45.5% vs 16.4%, P = .024).

Conclusions

HDV infection is rare in Ethiopia but is associated with more advanced liver fibrosis.
Corporate Mortality Files and Late Industrial Necropolitics
Authors: Little Peter C.
Published: October 2017

This article critically examines the corporate production, archival politics, and socio–legal dimensions of corporate mortality files (CMFs), the largest corporate archive developed by IBM to systematically document industrial exposures and occupational health outcomes for electronics workers. I first provide a history of IBM's CMF project, which amounts to a comprehensive mortality record for IBM employees over the past 40 years. Next, I explore a recent case in Endicott, New York, birthplace of IBM, where the U.S. National Institute for Occupational Safety and Health studied IBM's CMFs for workers at IBM's former Endicott plant. Tracking the production of the IBM CMF, the strategic avoidance of this source of big data as evidence for determining a recent legal settlement, alongside local critiques of the IBM CMF project, the article develops what I call “late industrial necropolitics.”
Experiences and lessons learned for delivery of micronutrient powders interventions
Authors: Reerink Ietje , Namaste Sorrel ML , Poonawala Alia , Nyhus Dhillon Christina , Aburto Nancy , Chaudhery Deepika , Kroeun Hou , Griffiths Marcia , Haque Mohammad Raisul , Bonvecchio Anabelle , Jefferds Maria Elena , Rawat Rahul
Published: October 2017

An effective delivery strategy coupled with relevant social and behaviour change communication (SBCC) have been identified as central to the implementation of micronutrient powders (MNP) interventions, but there has been limited documentation of what works. Under the auspices of “The Micronutrient Powders Consultation: Lessons Learned for Operational Guidance,” three working groups were formed to summarize experiences and lessons across countries regarding MNP interventions for young children. This paper focuses on programmatic experiences related to MNP delivery (models, platforms, and channels), SBCC, and training. Methods included a review of published and grey literature, interviews with key informants, and deliberations throughout the consultation process. We found that most countries distributed MNP free of charge via the health sector, although distribution through other platforms and using subsidized fee for product or mixed payment models have also been used. Community‐based distribution channels have generally shown higher coverage and when part of an infant and young child feeding approach, may provide additional benefit given their complementarity. SBCC for MNP has worked best when focused on meeting the MNP behavioural objectives (appropriate use, intake adherence, and related infant and young child feeding behaviours). Programmers have learned that reincorporating SBCC and training throughout the intervention life cycle has allowed for much needed adaptations. Diverse experiences delivering MNP exist, and although no one‐size‐fits‐all approach emerged, well‐established delivery platforms, community involvement, and SBCC‐centred designs tended to have more success. Much still needs to be learned on MNP delivery, and we propose a set of implementation research questions that require further investigation.
Experiences and lessons learned for programme improvement of micronutrient powders interventions
Authors: Vossenaar Marieke , Tumilowicz Alison , D'Agostino Alexis , Bonvecchio Anabelle , Grajeda Ruben , Imanalieva Cholpon , Irizarry Laura , Mulokozi Generose , Sudardjo Minarto Noto , Tsevegsuren Narantsetseg , Neufeld Lynnette M
Published: October 2017

Continual course correction during implementation of nutrition programmes is critical to address factors that might limit coverage and potential for impact. Programme improvement requires rigorous scientific inquiry to identify and address implementation pathways and the factors that affect them. Under the auspices of “The Micronutrient Powders Consultation: Lessons Learned for Operational Guidance,” 3 working groups were formed to summarize experiences and lessons across countries regarding micronutrient powder (MNP) interventions for young children. This paper focuses on how MNP interventions undertook key elements of programme improvement, specifically, the use of programme theory, monitoring, process evaluation, and supportive supervision. Methods included a review of published and grey literature, interviews with key informants, and deliberations throughout the consultation process. We found that although much has been written and published about the use of monitoring and process evaluation to inform MNP interventions at small scale, there has been little formal documentation of lessons for the transition from pilot to scaled implementation. Supervision processes and experiences are not documented, and to our knowledge, there is no evidence of whether they have been effective to improve implementation. Improving the efficiency and effectiveness of interventions requires identification of critical indicators for detecting implementation challenges and drivers of impact, integration with existing programmes and systems, strengthened technical capacity, and financing for implementation of effective monitoring systems. Our understanding of programme improvement for MNP interventions is still incomplete, especially outside of the pilot stage, and we propose a set of implementation research questions that require further investigation.
The effects of aging on notional defined contribution pension systems: A theoretical investigation
Authors: Patriarca Fabrizio
Published: October 2017

This paper proposes a theoretical framework for analyzing the properties of pay‐as‐you‐go notional defined contributions (NDCs) systems within the context of aging. Different from the defined‐benefit scheme, where aging harms the financial sustainability of the social security system, the NDC determines pension benefits while taking into account life expectancy and demographic trends, turning the issue of financial sustainability into one of pension adequacy. This paper explores the balance sheet effects when life expectancy, retirement thresholds and entry age in the labor market vary by cohorts. The study suggests some solutions for practical issues concerning aging in NDC systems, such as (a) the bias related to the forecasts of survival rates, (b) the indexation of pension benefits and (c) the setup of tenure and age requirements for retirement.
Biscay and Beyond? Prehistoric Voyaging between Two Finisterres
Authors: Callaghan Richard , Scarre Chris
Published: October 2017

The Atlantic peninsulas of western Europe present intriguing cultural parallels that reach back into later prehistory. Furthermore, direct evidence of interconnections from the fifth millennium BC is revealed by the movement of specific materials such as Iberian variscite. Brittany and Galicia were key nodes within this potential network of maritime interaction, but debate continues as to the routes that were chosen and the navigational abilities involved. Did early seafarers keep close to the coast and did long journeys involve many intermediate landfalls? Or did crews venture direct crossings of the Bay of Biscay? In the absence of surviving evidence for the kinds of vessel likely to have been used by Neolithic seaborne navigators, modern wind and current data are here used to generate models indicating journey times for small sea‐going craft powered only by oars, following the coastal or the direct route. The results are discussed within the context of selected material flows (jadeitite, variscite, copper, Beakers) and against a background of potentially changing maritime technology.
Ontogenetic trajectories of septal spacing in Early Jurassic belemnites from Germany and France, and their palaeobiological implications
Authors: Wani Ryoji , Tajika Amane , Ikuno Kenji , Iwasaki Tetsuro
Published: October 2017

Based on well‐preserved belemnites, the ontogenetic trajectories of septal spacing between succeeding chambers were analysed. In the examined species (Passaloteuthis laevigata,Parapassaloteuthis zieteniandPseudohasitites longiformis) that come from Buttenheim, Germany, and Lixhausen, France, the ontogenetic trajectories of septal spacing follow exponentially increasing trends with no decreasing phase of septal crowding during the earliest ontogenetic stage. The absence of a decreasing trend at the earliest ontogenetic stage is a unique character in contrast with those in modern cuttlefish and ancient and modern nautiloids, in which the decreasing trends are related to hatching events. These ontogenetic septal spacing trends suggest that the belemnite hatchlings had only a protoconch with no chamber. These belemnite hatchlings with no chamber and therefore small embryonic shell diameter are similar to those of ammonoids. Significant difference in a statistical test that compared the protoconch size between the two localities, might suggest that there was limited transportation at the embryonic stage, although it could also just indicate differences in regional environmental conditions, age and/or degree of time averaging which might differ between the examined taxa.
Whole‐slide imaging at primary pathological diagnosis: Validation of whole‐slide imaging‐based primary pathological diagnosis at twelve Japanese academic institutes
Authors: Tabata Kazuhiro , Mori Ichiro , Sasaki Takeshi , Itoh Tomoo , Shiraishi Taizo , Yoshimi Naoki , Maeda Ichiro , Harada Oi , Taniyama Kiyomi , Taniyama Daiki , Watanabe Mika , Mikami Yoshiki , Sato Shuntaro , Kashima Yukio , Fujimura Shota , Fukuoka Junya
Published: October 2017

Several reports have demonstrated the use of whole‐slide imaging (WSI) for primary pathological diagnosis, but no such studies have been published from Asia. We retrospectively collected 1070 WSI specimens from 900 biopsies and small surgeries conducted in nine hospitals. Nine pathologists, who participated in this study, trained for the College of American Pathologists guidelines, reviewed the specimens and made diagnoses based on digitized, 20× or 40× optically magnified images with a WSI scanner. After a washout interval of over 2 weeks, the same observers reviewed conventional glass slides and diagnosed them by light microscopy. Discrepancies between microscopy‐ and WSI‐based diagnoses were evaluated at the individual institutes, and discrepant cases were further reviewed by all pathologists. Nine diagnoses (0.9%) showed major discrepancies with significant clinical differences between the WSI‐ and microscopy‐based diagnoses, and 37 (3.5%) minor discrepancies occurred without a clinical difference. Eight out of nine diagnoses with a major discrepancy were considered concordant with the microscopy‐based diagnoses. No association was observed between the level of discrepancy and the organ type, collection method, or digitized optical magnification. Our results indicate the availability of WSI‐based primary diagnosis of biopsies and small surgeries in routine daily practice.
Germinate to exterminate: chemical stimulation of Spongospora subterranea resting spore germination and its potential to diminish soil inoculum
Authors: Balendres M. A. , Clark T. J. , Tegg R. S. , Wilson C. R.
Published: October 2017

Hoagland's solution (HS), a defined nutrient supplement for plants, has been previously reported to stimulate zoospore release from resting spores of the potato pathogen Spongospora subterranea f. sp. subterranea. This study obtained direct empirical evidence for an increase in zoospore release with HS treatment, and identified Fe‐EDTA as the stimulant component of HS. Stimulation of resting spores by HS and Fe‐EDTA resulted in greater and earlier zoospore release compared to a distilled water control, and in the presence of a susceptible tomato host plant resulted in enhanced root infection. Given the labile nature of S. subterranea zoospores, it was postulated that stimulation of premature release of zoospores from the dormant resting spores in absence of susceptible hosts could reduce soil inoculum levels. In two glasshouse trials in the absence of host plants, both Fe‐EDTA and HS soil treatments reduced S. subterranea soil inoculum levels, providing proof of concept for the ‘germinate to exterminate’ approach to inoculum management.
Optimizing seeding density of fast‐growing native trees for restoring the Brazilian Atlantic Forest
Authors: Meli Paula , Isernhagen Ingo , Brancalion Pedro H. S. , Isernhagen Elaine C. C. , Behling Maurel , Rodrigues Ricardo R.
Published: October 2017

Direct seeding is a promising method for reducing restoration costs, but methodological adjustments are still needed to reduce the uncertainties to achieve a desired seedling density in the field. Here, we investigated the technical approaches and outcomes of direct seeding of fast‐growing native trees for cost‐effective restoration of the Brazilian Atlantic Forest. Sixteen tree species were manually sown at three seeding densities in planting lines prepared with a subsoiler, in two experimental areas, which were weeded with hoes and had leaf‐cutter ants controlled with insecticide baits. Seedling density was monitored for 30, 90, and 180 days after sowing. No substantial change in tree density was observed 30 days after sowing, thus allowing fast corrective actions to adjust tree density. Only a minor proportion of the sown viable seeds resulted in established seedlings at 180 days (4–12% for the community; approximately 25% for the species with the best performance). However, tree density was high (6,000 on average; approximately 1,400–13,000 trees/ha) and allowed an effective canopy development. Overall, seedling density was linearly and positively associated with seeding density, was highly influenced by the species used, and was higher in the soil with higher sum of bases. Buying seeds would be, for most species, less costly than buying nursery‐grown seedlings for achieving the expected tree densities in the field. These results evidence the potential of direct seeding for reducing restoration costs, as well as the need to select species with better performance and adjust seeding densities to optimize the use of this method.
Multiscale metrics differentiate among tallgrass prairie restorations and remnant ecosystems along a restorative continuum
Authors: Sluis William J. , Bowles Marlin , Jones Mike
Published: October 2017

Most grassland restorations continue to fall short of achieving diversity levels found in reference ecosystems due primarily to establishment methods and species pool limits, and a diversity of metrics may be needed to assess how different restoration methods compare to reference sites. We addressed the extent to which 17 Midwest North American grassland reference systems and 18 restorations represent a compositional gradient, how hierarchical alpha, beta, and gamma diversity vary across this gradient, and how reference ecosystems and restorations differ in functional group diversity. Hierarchical cluster analysis separated reference and restoration sites groups based on alpha and gamma scales. Both were significantly correlated with species richness gradients at nonmetric multidimensional scaling ordination axes and indicator species. Most metrics were significantly correlated, and reference sites had significantly greater diversity than restorations at multiple scales. Reference sites also differed due to the absence of a subset of species from sites with disturbance history and restorations differed in response to restoration methods. Restorations using repeated establishment events from larger species pools achieved reference site alpha diversity and had greater representation of species that characterize undisturbed reference sites. Restorations using a single establishment event resembled disturbed reference sites. However, all restorations represented a subset of reference sites, including functional group diversity. As a result, they fail to conserve rare species that occur among reference sites and may lack temporal stability. Representation of rare species among restorations would help meet regional conservation needs without increasing alpha diversity.
Rationality, Virtue, and Faith: Can We Find a Pro‐Theology Philosophy?Rationality as Virtue: Towards a Theological Philosophy, LydiaSchumacher, Ashgate, 2015 (ISBN 978‐1‐4724‐4265‐9), xii + 230 pp., hb £65Theological Philosophy: Rethinking the Rationality of Christian Faith, LydiaSchumacher, Ashgate, 2015 (ISBN 978‐1‐4724‐4262‐8), xii + 210 pp., hb £60
Authors: Pattison George
Published: October 2017

Lydia Schumacher's two‐volume essay in constructive philosophical theology is an attempt to model a new approach to the relationship between philosophy and theology that might offer a constructive and positive response to the way in which many modern conceptions of rationality involve skepticism about the rationality of faith. Having laid the foundations of this approach in Volume 1 (Rationality as Virtue), Volume 2 develops what the author calls a pro‐theology philosophy. Both parts rely strongly, though not slavishly, on Aquinas, and, as in Thomist thought, the anthropological starting point is a view of the human being as a rational animal. This is an impressive project, but by taking its point of departure in such a view of the human essence, Schumacher's project is isolated from major currents of modern philosophy. Questions are also raised about the transition to Trinitarian theology and the lack of worked examples, the latter making it difficult to see just how this ‘pro‐theology philosophy’ would relate to concrete issues of life.
Is there Theology in this Book?The Theology of Augustine's Confessions, PaulRigby, Cambridge University Press, 2015 (ISBN 978‐1107094925), xv + 340 pp., hb £67Augustine's Confessions: Philosophy in Autobiography, William E.Mann (ed.), Oxford University Press, 2014 (ISBN 978‐0199577552), xi +223 pp., hb £36The Space of Time: A Sensualist Interpretation of Time in Augustine, Confessions X to XII, DavidvanDusen, Brill, 2014 (ISBN 978‐9004266865), xv + 358 pp., hb €149Confessions: Books 1–8, Augustine of Hippo, trans. Carolyn J.‐B. Hammond, Harvard University Press, 2014 (ISBN 978‐0674996854), lxv + 413 pp., hb $26Confessions: Books 9–13, Augustine of Hippo, trans. Carolyn J.‐B. Hammond, Harvard University Press, 2016, (ISBN 978‐0674996939), xlii + 446 pp., hb $26Confessions, Augustine of Hippo, trans. Sarah Ruden, The Modern Library, 2017 (ISBN 978‐0812996562), xli + 484 pp., $28
Authors: Teubner Jonathan D.
Published: October 2017

This review essay discusses three recent books on, and two new translations of, Augustine's Confessions. Long appreciated for its stylistic beauty and existential profundity, the Confessions has recently become a resource for creative philosophical reflection in both the analytic and continental traditions. However, there has not been a recent theological treatment of the Confessions, a curious lacuna considering Augustine's importance for the history of Christian doctrine. This review probes three recent works – Paul Rigby's The Theology of Augustine's Confessions, Gareth Matthews' edited collection Augustine's Confessions: Philosophy in Autobiography, and David van Dusen's The Space of Time: A Sensualist Interpretation of Time in Augustine, Confessions X to XII – for how they in turn attempt to address, avoid, and reject the theological subject matter within the text. In each of them, a reader can discern an effort to translate Augustine's language into a contemporary idiom that strays from traditional doctrinal locution. Two new English translations by Carolyn J.‐B. Hammond and Sarah Ruden demonstrate that conveying the theology within the Confessions is a challenge even at the granular level of textual translation. This review concludes by considering how this theological lacuna might be filled, considering the complexity of Augustine's language, argument, and self‐presentation that has made this text more than simply another work of theology.
Can Risk‐Averse Households Make Risky Investments? The Role of Trust in Others
Authors: Bucciol Alessandro , Cavasso Barbara , Zarri Luca
Published: October 2017

In this paper, using data from the Survey on Health, Ageing and Retirement in Europe (SHARE, 2006 and 2013 waves), we illustrate the link between individuals’ attitudes to financial risk combined with their willingness to trust others, and their investments in risky assets. Individuals who display either risk tolerance alone or – to a lesser extent – risk aversion and trust more frequently decide to buy risky assets. The comparison between Scandinavian and Mediterranean countries indicates that trust plays qualitatively different roles depending on the prevailing combination of risk attitude and trust in the area being studied.
The Productivist Construction of Selective Welfare Pragmatism in China
Authors: Mok Ka Ho , Kühner Stefan , Huang Genghua
Published: October 2017

This article discusses whether Mainland China under the Hu Jintao and Wen Jiabao leadership (2003–13) has developed a new welfare settlement, the emphasis of which is to shift away from a ‘productivist’ focus on education and healthcare investment towards a more ‘protective’ approach, characterized by investing into social protection and establishing a minimum living guarantee for both the urban and rural poor. In so doing, this article reviews the conceptual debate on Chinese social policy development and explores whether there is any evidence to substantiate a gradual decrease of fragmentation in social provision among the Chinese provinces. With regard to the former question, the article finds that the various social policy initiatives have yet to amount to a qualitative shift in the core foundation of the human capital‐focused welfare production logic in China. With regard to the latter question, we argue that considerable fragmentation of social provision at the Chinese provincial level continues to hamper attempts to define a coherent Chinese social model. Indeed, we find considerable diversity in terms of the co‐operative state‐local interactions within China leading to varying trajectories of social decentralization. Unlike much of the current research in comparative social policy analysis, which continues to treat Mainland China as a single case, this article provides a strong account of a productivist construction of selective welfare pragmatism, which reproduces social policy gaps for different groups of the Chinese population, and suggests that determining multiple ‘welfare types’ within China might be the most fruitful path for future academic inquiry.
A Districtwide Study of Automaticity When Included in Concept‐Based Elementary School Mathematics Instruction
Authors: McGee Daniel , Richardson Patrick , Brewer Meredith , Gonulates Funda , Hodgson Theodore , Weinel Rebecca
Published: October 2017

While conceptual understanding of properties, operations, and the base‐ten number system is certainly associated with the ability to access math facts fluently, the role of math fact memorization to promote conceptual understanding remains contested. In order to gain insight into this question, this study looks at the results when one of three elementary schools in a school district implements mandatory automaticity drills for 10 minutes each day while the remaining two elementary schools, with the same curriculum and very similar demographics, do not. This study looks at (a) the impact that schoolwide implementation of automaticity drills has on schoolwide computational math skills as measured by the ITBS and (b) the relationship between automaticity and conceptual understanding as measured by statewide standardized testing. The results suggest that while there may be an association between automaticity and higher performance on standardized tests, caution should be taken before assuming there are benefits to promoting automaticity drills. These results are consistent with those that support a process‐driven approach to automaticity based on familiarity with properties and strategies associated with the base‐ten number system; they are not consistent with those that support an answer‐driven approach to automaticity based on memorization of answers.
A novel HLA‐A*02 allele, A*02:692, was identified by sequencing‐based typing
Authors: Zhu Y.‐L. , Han B. , Chi X.‐Y. , Hu B. , Feng Z.‐H.
Published: October 2017

One nucleotide replacement at nucleotide 811 of HLA‐A*02:01:01:01 results in a new allele, HLA‐A*02:692.
Luther, learning, and the liberal arts
Authors: Burnett Amy Nelson
Published: October 2017

The learning goals of a well‐designed course in the liberal arts include not only the imparting of knowledge but also the development of critical thinking and disciplinary expertise. A class on Luther can help students acquire those intellectual skills associated with the discipline of history and the liberal arts more generally as they consider broader questions about institutional religion, spirituality, moral choices, and human agency. Current scholarship on how people learn highlights the importance of adequate mental frameworks for the acquisition, retention, and retrieval of new ideas and information. This scholarship underlies the choice of specific strategies used to teach about Luther and the Reformation. Assignments provide “scaffolding,” which begins with modeling and then moves from simpler to more complex assignments. Students practice the specific intellectual skills of critical reading and textual analysis over the course of the semester.
Grading matters in theological education
Authors: Blodgett Barbara J.
Published: October 2017

Grading systems matter more to the teaching and learning enterprise than many teachers may realize, as demonstrated in the author's experience of adopting a new one. Different systems emphasize different values such as excellence vs. perfection, achievement vs. talent, and second chances vs. partial credit. The author relates her experiment with specifications grading, an outcome‐based, pass/fail, rubric‐based, and contractual grading system, and demonstrates its promise. She then addresses three questions her experiment raised:Should I grade at all and if so, toward what end? Exactly what am I grading when I grade? andIs there any way to lessen the sting of failure?
High Momentum Jet Flames at Elevated Pressure: Detailed Investigation of Flame Stabilization With Simultaneous Particle Image Velocimetry and OH-LIF
Authors: Severin Michael , Lammel Oliver , Ax Holger , Lückerath Rainer , Meier Wolfgang , Aigner Manfred , Heinze Johannes
Published: October 2017

A model FLOX® combustor, featuring a single high momentum premixed jet flame, has been investigated using laser diagnostics in an optically accessible combustion chamber at a pressure of 8 bar. The model combustor was designed as a large single eccentric nozzle main burner (Ø 40 mm) together with an adjoining pilot burner and was operated with natural gas. To gain insight into the flame stabilization mechanisms with and without piloting, simultaneous particle image velocimetry (PIV) and OH laser-induced fluorescence (LIF) measurements have been performed at numerous two-dimensional (2D) sections of the flame. Additional OH-LIF measurements without PIV particles were analyzed quantitatively resulting in absolute OH concentrations and temperature fields. The flow field looks rather similar for both the unpiloted and the piloted cases, featuring a large recirculation zone next to the high momentum jet. However, flame shape and position change drastically. For the unpiloted case, the flame is lifted and widely distributed. Isolated flame kernels are found at the flame root in the vicinity of small-scale vortices. For the piloted flame, on the other hand, both pilot and main flame are attached to the burner base plate, and flame stabilization seems to take place on much smaller spatial scales with a connected flame front and no isolated flame kernels. The single-shot analysis gives rise to the assumption that for the unpiloted case, small-scale vortices act like the pilot burner flow in the opposed case and constantly impinge and ignite the high momentum jet at its root.
Modeling Strategies for Large Eddy Simulation of Lean Burn Spray Flames
Authors: Puggelli S. , Bertini D. , Mazzei L. , Andreini A.
Published: October 2017

Over the last years, aero-engines are progressively evolving toward design concepts that permit improvements in terms of engine safety, fuel economy, and pollutant emissions. With the aim of satisfying the strict NOx reduction targets imposed by ICAO-CAEP, lean burn technology is one of the most promising solutions even if it must face safety concerns and technical issues. Hence, a depth insight on lean burn combustion is required, and computational fluid dynamics can be a useful tool for this purpose. In this work, a comparison in large eddy simulation (LES) framework of two widely employed combustion approaches like the artificially thickened flame (ATF) and the flamelet generated manifold (FGM) is performed using ANSYS fluent v16.2. Two literature test cases with increasing complexity in terms of geometry, flow field, and operating conditions are considered. First, capabilities of FGM are evaluated on a single swirler burner operating at ambient pressure with a standard pressure atomizer for spray injection. Then, a second test case, operated at 4 bar, is simulated. Here, kerosene fuel is burned after an injection through a prefilming airblast atomizer within a corotating double swirler. Obtained comparisons with experimental results show different capabilities of ATF and FGM in modeling the partially premixed behavior of the flame and provide an overview of the main strengths and limitations of the modeling strategies under investigation.
Adaptive and Real-Time Optimal Control of Stick–Slip and Bit Wear in Autonomous Rotary Steerable Drilling
Authors: Kamel Mahmoud A. , Elkatatny Salaheldin , Mysorewala Muhammad Faizan , Al-Majed Abdulaziz , Elshafei Moustafa
Published: October 2017

Deviated, horizontal, and multilateral wells are drilled to increase the contact area between the well path and the reservoir and as a result, the well productivity will be increased. Directional steering systems (DSS) are used to control the direction in nonvertical wells. Rotary steerable system (RSS) is the current state of the art of DSS. In this research, the problem of real-time control of autonomous RSS with unknown formation rock strength was presented. The aim of this study is to develop a real-time control scheme for real-time optimization of drilling parameters to (1) maximize the rate of penetration (ROP), (2) minimize the deviation from the planned well bore trajectory, (3) reduce the stick–slip oscillations, and (4) assess the degree of bit wear. Nonlinear model for the drilling operation was developed using energy balance equation, where rock specific energy (RSE) is used to calculate the minimum power required for a given ROP. A proposed mass spring system was used to represent the phenomena of stick–slip oscillation. The model parameters have been adaptively estimated at each control iteration to tackle any disturbances or variations in the formation properties. The bit wear is mathematically represented using Bourgoyne model. Detailed mathematical formulation and computer simulation were used for evaluation of the performance of the proposed technique based on real well field data. The obtained results showed excellent ability to accommodate the changes in the formation properties. In addition, the rates of bit wear and stick–slip oscillations have been optimized.
Natural Convection Heat Transfer Experiments in Fluoride Salt
Authors: Yoder Graydon L. , Heatherly Dennis , Caja Mario
Published: October 2017

A liquid fluoride salt experiment has been constructed and used to acquire natural convection heat transfer data. The experiment used FLiNaK salt in a small cell that included a cylindrical electrical heater, 1.27 cm in diameter, oriented vertically in a FLiNaK bath. Thermocouples internal to the heater were used, along with FLiNaK temperature measurements and heater power measurements, to determine natural circulation heat transfer coefficients. These data were acquired for Rayleigh numbers ranging from 3 × 105 to 8 × 109 and salt temperatures from 560 °C to 640 °C. Test results show that measured heat transfer coefficients are consistent with conventional natural convection heat transfer coefficients for cylinders, but the average error can be as high as 20% using these correlations. Correlations developed by fitting the data for this experiment show much lower errors (<10%).
Isolated and Coupled Effects of Rotating and Buoyancy Number on Heat Transfer and Pressure Drop in a Rotating Two-Pass Parallelogram Channel With Transverse Ribs
Authors: Liou Tong-Miin , Chang Shyy Woei , Lan Yi-An , Chan Shu-Po
Published: October 2017

Detailed Nusselt number (Nu) distributions over the leading (LE) and trailing (TE) endwalls and the pressure drop coefficients (f) of a rotating transverse-ribbed two-pass parallelogram channel were measured. The impacts of Reynolds (Re), rotation (Ro), and buoyancy (Bu) numbers upon local and regionally averaged Nu over the endwall of two ribbed legs and the turn are explored for Re = 5000–20,000, Ro = 0–0.3, and Bu = 0.0015–0.122. The present work aims to study the combined buoyancy and Coriolis effects on thermal performances as the first attempt. A set of selected experimental data illustrates the isolated and interdependent Ro and Bu influences upon Nu with the impacts of Re and Ro on f disclosed. Moreover, thermal performance factors (TPF) for the tested channel are evaluated and compared with those collected from the channels with different cross-sectional shapes and endwall configurations to enlighten the relative heat transfer efficiency under rotating condition. Empirical Nu and f correlations are acquired to govern the entire Nu and f data generated. These correlations allow one to evaluate both isolated and combined Re, Ro and/or Bu impacts upon the thermal performances of the present rotating channel for internal cooling of gas turbine blades.
Secondary Flow and Entropy Generation of Laminar Mixed Convection in the Entrance Region of a Horizontal Square Duct
Authors: Huang Y. Y. , Zhang L. J. , Yang G. , Wu J. Y.
Published: October 2017

The flow structure, heat transfer, and entropy generation characteristics in the entrance region of mixed convection under the effect of transverse buoyancy force are investigated numerically. Results are obtained for laminar flow of uniform inlet velocity and temperature through a square duct with uniform wall temperature. The buoyancy induced-secondary flow is observed in the entrance region where flow structure and heat transfer are significantly affected. The flow entrance region is extended by buoyancy, while the thermal entrance region is shortened. The developments of Nusselt number and local entropy generation are discussed in detail for Richardson numbers of 0 ≤ Ri ≤ 10, Reynolds number Re = 100 and Prandtl number Pr = 0.7. The total heat transfer rate and global entropy generation by friction increase with buoyancy, while global entropy generation by heat convection changes a little. The effect of Reynolds number on entropy generation is also discussed.
Optimization of Electro Discharge Machining Process Parameters With Fuzzy Logic for Stainless Steel 304 (ASTM A240)
Authors: Ubaid Alaa M. , Dweiri Fikri T. , Aghdeab Shukry H. , Abdullah Al-Juboori Laith
Published: October 2017

Electro discharge machining (EDM) process need to be optimized when a new material invented or even if some process variables changed. This process has many variables and it is always difficult to get the optimum set of variables by chance. Therefore, an optimization process need to be conducted considering different combinations of machining parameters as well as other variables even if the process were optimized for a certain set of variables. Optimization of the EDM process for machining stainless steel 304 (SS304) (ASTM A240) was studied in this paper. Signal-to-noise ratio (S/N) was calculated for each performance measures, and multi response performance index (MRPI) was generated using fuzzy logic inference system. Optimal machining parameters for machining SS304 materials were identified, namely current 10, pulse on time 60 μs, and pulse off time 35 μs. Analyses of variances (ANOVA) method was used as well to see which machining parameter has significant effect on the performance measures. The result of ANOVA indicates that pulse off time and current are the most significant machining parameters in affecting the performance measures, with the pulse off time being the most significant parameter.
Uniform sputter deposition of high-quality epitaxial complex oxide thin films
Authors: Brewer A. , Cho K. H. , Saenrang W. , Baek S. H. , Frederick J. C. , Eom C. B.
Published: October 2017

Uniform deposition of high-quality epitaxial complex oxide thin films over a large area is desirable not only for the large scale fabrication of oxide electronics but also for preparing multiple samples with the same growth conditions for various characterization techniques. However, it is particularly challenging to grow uniform thin films of multicomponent oxide systems containing volatile species such as Pb and Bi. By combining a misaligned parallel dual planar magnetron sputtering technique with substrate rotation, the authors have grown uniform epitaxial thin films piezoelectric 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 and multiferroic monodomain BiFeO3 with high-deposition rates over a 2 in. diameter area. These films have excellent uniformity of thickness, stoichiometric compositions, and electrical properties. This technique can be scaled to larger deposition areas by using larger sputtering targets and widely applied to various multicomponent complex oxide thin film heterostructures.
Comparison of psychoacoustic-based reverberance parameters
Authors: Lee Doheon , van Dorp Schuitman Jasper , Cabrera Densil , Qiu Xiaojun , Burnett Ian
Published: October 2017

This study compared psychoacoustic reverberance parameters to each other, as well as to reverberation time (RT) and early decay time (EDT) under various acoustic conditions. The psychoacoustic parameters were loudness-based RT (TN), loudness-based EDT [EDTN; Lee, Cabrera, and Martens, J. Acoust. Soc. Am. 131, 1194–1205 (2012a)], and parameter for reverberance [PREV; van Dorp Schuitman, de Vries, and Lindau., J. Acoust. Soc. Am. 133, 1572–1585 (2013)]. For the comparisons, a wide range of sound pressure levels (SPLs) from 20 dB to 100 dB and RTs from 0.5 s to 5.0 s were evaluated, and two sets of subjective data from the previous studies were used for the cross-validation and comparison. Results of the comparisons show that the psychoacoustic reverberance parameters provided better matches to reverberance than RT and EDT; however, the performance of these psychoacoustic reverberance parameters varied with the SPL range, the type of audio sample, and the reverberation conditions. This study reveals that PREV is the most relevant for estimating a relative change in reverberance between samples when the SPL range is small, while EDTN is useful in estimating the absolute reverberance. This study also suggests the use of PREV and EDTN for speech and music samples, respectively.
Multicellularity enriches the entrainment of
Arabidopsis
circadian clock
Authors: Masuda Kosaku , Kitaoka Ryota , Ukai Kazuya , Tokuda Isao T. , Fukuda Hirokazu
Published: October 2017

Novel methods reveal how single-cell behavior translates to organism level in phase response properties of plant circadian clocks.
Webinar | Overcoming the evils of fixation and storage: Getting the most out of your FFPE samples
Authors: Gupta Manu , (Zhihong) Zhang Joe , Strengman Eric E
Published: October 2017

The vast majority of clinical samples are still archived using a decades-old technique of fixation with formaldehyde and embedding in paraffin wax to generate so-called formalin-fixed paraffin-embedded (FFPE) tissue blocks. This process of fixation and embedding, as well as long-term storage, can result in severe degradation of nucleic acids in the tissue. The fixation process itself causes cross-linkage between nucleic acids and proteins, as well as covalent modification of nucleic acids by monomethylol (-CH
2
OH) addition to the bases. Millions of FFPE blocks form the foundation of many tissue archives worldwide, and are essential to clinical research for exploring disease pathways and developing novel therapies. The inherent challenges of obtaining useable nucleic acids from difficult sample types such as these can be overcome by using the latest technologies and procedures to provide meaningful results throughout the next-generation sequencing workflow, from initial extraction of DNA/RNA to sample quantification, sample quality control, and library preparation.
Trio surfs gravitational waves to Nobel glory
Authors: Cho Adrian
Published: October 2017

Testy debate over who should win defused by potential laureate's death.
Treaty tested by space miners
Authors: Clery Daniel
Published: October 2017

Emboldened by national laws, companies push the limits of 50-year-old Outer Space Treaty.
Against the grain
Authors: Cornwall Warren
Published: October 2017

Forest scientist Jerry Franklin became known for helping protect old-growth trees from logging. Now, he's arguing for letting the chainsaws loose in some forests.
Archaeology in a divided land
Authors: Gannon Megan
Published: October 2017

Cyprus's bitter political stalemate hampers studies of the world's first farmers.
The Rydberg constant and proton size from atomic hydrogen
Authors: Beyer Axel , Maisenbacher Lothar , Matveev Arthur , Pohl Randolf , Khabarova Ksenia , Grinin Alexey , Lamour Tobias , Yost Dylan C. , Hänsch Theodor W. , Kolachevsky Nikolai , Udem Thomas
Published: October 2017

How big is the proton?

The discrepancy between the size of the proton extracted from the spectroscopy of muonic hydrogen and the value obtained by averaging previous results for “regular” hydrogen has puzzled physicists for the past 7 years. Now, Beyer
et al.
shed light on this puzzle (see the Perspective by Vassen). The authors obtained the size of the proton using very accurate spectroscopic measurements of regular hydrogen. Unexpectedly, this value was inconsistent with the average value of previous measurements of the same type. Also unexpectedly, it was consistent with the size extracted from the muonic hydrogen experiments. Resolving the puzzle must now include trying to understand how the old results relate to the new, as well as reexamining the sources of systematic errors in all experiments.

Science
, this issue p.
79
; see also p.
39
Visualizing the function and fate of neutrophils in sterile injury and repair
Authors: Wang Jing , Hossain Mokarram , Thanabalasuriar Ajitha , Gunzer Matthias , Meininger Cynthia , Kubes Paul
Published: October 2017

Imaging the unforeseen fate of neutrophils

Inflammation that results from insults such as ischemia and reperfusion or trauma in the absence of microorganisms is known as “sterile inflammation.” Neutrophils are recruited in vast numbers during sterile inflammation and have been thought to play a detrimental role. Wang
et al.
used intravital microscopy to show that neutrophils actually perform helpful tasks such as removing and regenerating thermally damaged blood vessels in the liver (see the Perspective by Garner and de Visser). Moreover, neutrophils neither die nor are phagocytosed. Instead, they return to the circulation in a process called “reverse transmigration,” making a pit stop in the lungs, before ending their lives where they began—in the bone marrow. Thus, a reconsideration of the use of anti-neutrophil therapies after injury may be warranted.

Science
, this issue p.
111
; see also p.
42
Long-term pattern and magnitude of soil carbon feedback to the climate system in a warming world
Authors: Melillo J. M. , Frey S. D. , DeAngelis K. M. , Werner W. J. , Bernard M. J. , Bowles F. P. , Pold G. , Knorr M. A. , Grandy A. S.
Published: October 2017

Climate and the carbon cycle

It is still not clear how global warming will affect the global carbon cycle, either in terms of the magnitude of the effect or even its sign. Help in answering that question will come from long-term field-based experiments designed to explore carbon cycle-climate feedbacks in an ecosystem context. Melillo
et al.
performed a 26-year soil-warming experiment in a mid-latitude hardwood forest (see the Perspective by Metcalfe). Warming has resulted in a complex pattern of net carbon loss from the soil. These results support projections of a long-term, positive carbon feedback from similar ecosystems as the world warms.

Science
, this issue p.
101
; See also p.
41
Spatiotemporal mode-locking in multimode fiber lasers
Authors: Wright Logan G. , Christodoulides Demetrios N. , Wise Frank W.
Published: October 2017

Harnessing complexity in laser light

The development of lasers and the quality of the output light has been crucially dependent on understanding and being able to control the process occurring within the laser-generating cavity. In a real laser cavity, there are both longitudinal and transverse modes; for the highest-quality lasers, reducing the effects of the latter has been standard practice. However, using a graded index fiber cavity, Wright
et al.
demonstrate that the longitudinal and transverse modes can be locked to provide an output of complex coherent light. Harnessing, rather than filtering out, the transverse modes could produce a valuable and flexible light source applicable across a broad range of disciplines.

Science
, this issue p.
94
Deciphering dueling analyses of clean water regulations
Authors: Boyle Kevin J. , Kotchen Matthew J. , Smith V. Kerry
Published: October 2017

Hundreds of millions of dollars in benefits were discarded
Type I interference with self-tolerance
Authors: Clark Rachael A.
Published: October 2017

Common variant of the RNA sensor IFIH1 enhances antiviral responses but also increases the risk of autoimmune disease.
Differential abundance of CK1α provides selectivity for pharmacological CK1α activators to target WNT-dependent tumors
Authors: Li Bin , Orton Darren , Neitzel Leif R. , Astudillo Luisana , Shen Chen , Long Jun , Chen Xi , Kirkbride Kellye C. , Doundoulakis Thomas , Guerra Marcy L. , Zaias Julia , Fei Dennis Liang , Rodriguez-Blanco Jezabel , Thorne Curtis , Wang Zhiqiang , Jin Ke , Nguyen Dao M. , Sands Laurence R. , Marchetti Floriano , Abreu Maria T. , Cobb Melanie H. , Capobianco Anthony J. , Lee Ethan , Robbins David J.
Published: October 2017

A small-molecule CK1α activator inhibits the growth of WNT-driven intestinal tumors without toxicity to normal epithelium.