bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of multigrid algorithms for high‐order continuous finite element discretizations
Authors: Sundar Hari , Stadler Georg , Biros George
Published: April 2015

We present a comparison of different multigrid approaches for the solution of systems arising from high‐order continuous finite element discretizations of elliptic partial differential equations on complex geometries. We consider the pointwise Jacobi, the Chebyshev‐accelerated Jacobi, and the symmetric successive over‐relaxation smoothers, as well as elementwise block Jacobi smoothing. Three approaches for the multigrid hierarchy are compared: (1) high‐order h‐multigrid, which uses high‐order interpolation and restriction between geometrically coarsened meshes; (2) p‐multigrid, in which the polynomial order is reduced while the mesh remains unchanged, and the interpolation and restriction incorporate the different‐order basis functions; and (3) a first‐order approximation multigrid preconditioner constructed using the nodes of the high‐order discretization. This latter approach is often combined with algebraic multigrid for the low‐order operator and is attractive for high‐order discretizations on unstructured meshes, where geometric coarsening is difficult. Based on a simple performance model, we compare the computational cost of the different approaches. Using scalar test problems in two and three dimensions with constant and varying coefficients, we compare the performance of the different multigrid approaches for polynomial orders up to 16. Overall, both h‐multigrid and p‐multigrid work well; the first‐order approximation is less efficient. For constant coefficients, all smoothers work well. For variable coefficients, Chebyshev and symmetric successive over‐relaxation smoothing outperform Jacobi smoothing. While all of the tested methods converge in a mesh‐independent number of iterations, none of them behaves completely independent of the polynomial order. When multigrid is used as a preconditioner in a Krylov method, the iteration number decreases significantly compared with using multigrid as a solver. Copyright © 2015 John Wiley & Sons, Ltd.
Secondary histiocytic sarcoma may cause apparent persistence or recurrence of minimal residual disease in childhood acute lymphoblastic leukemia
Authors: Alten Julia , Klapper Wolfram , Leuschner Ivo , Eckert Cornelia , Beier Rita , Vallo Elisabeth , Krause Martin , Claviez Alexander , Vieth Simon , Bleckmann Kirsten , Möricke Anja , Schrappe Martin , Cario Gunnar
Published: April 2015

Histiocytic sarcoma (HS) is a rare disease with poor prognosis which may develop subsequent to acute lymphoblastic leukemia (ALL). Here we report two children treated within the AIEOP‐BFM ALL 2009 trial: one patient succumbed to fulminant hemophagocytic lymphohistiocytosis triggered by HS during ALL maintenance therapy, the other patient had a smoldering course of HS for over 2 years, and subsequently died after allogeneic stem cell transplantation. In both cases, HS and ALL were clonally related and apparent return of minimal residual disease (MRD) was detected by qPCR in bone marrow. Thus, HS should be considered in ALL when MRD appears to persist or reappear. Pediatr Blood Cancer 2015;62:1656–1660. © 2015 Wiley Periodicals, Inc.
Hydroxyurea lowers transcranial Doppler flow velocities in children with sickle cell anaemia in a Nigerian cohort
Authors: Lagunju IkeOluwa , Brown Biobele J. , Sodeinde Olugbemiro
Published: April 2015

Background

Sickle cell anaemia (SCA) is the leading genetic disorder in Nigeria. Elevated velocities ≥170 cm/sec occur in about a third of Nigerian children with SCA. Chronic blood transfusion for stroke prevention is faced with a myriad of challenges in our practice.

Objectives

To evaluate the effectiveness of hydroxyurea (HU) in reducing flow velocities in a cohort of Nigerian children with SCA and elevated velocities treated with HU.

Methods

An observational study was carried out on a cohort of Nigerian children with SCA and elevated velocities identified on routine transcranial Doppler (TCD) screening. HU was recommended in those with TCD velocities ≥ 170cm/sec as stipulated in our hospital protocol. Outcomes were compared after ≥12 months of observation.

Results

Fifty children with elevated TCD velocities were studied; 31 consented to HU therapy and 19 declined. Children on HU showed a statistically significant decline in mean velocities from 199.7 [17.1] cm/sec to 165.8 [20.7] cm/sec (P < 0.001) with a significant increase in mean packed cell volume from 21.1 [3.4] to 25.0 [2.8]%. Children without treatment had a significant rise in mean velocities from 190.2 [10.8] cm/sec to 199.7 [14.9] cm/sec (P = 0.003). Children with conditional risk velocities on HU were less likely to convert to abnormal risk (P < 0.001). Two stroke events occurred, one in each group. No adverse effects of HU were recorded in the cohort.

Conclusion

HU appears to significantly reduce TCD velocities in Nigerian children with SCA and elevated velocities ≥170 cm/sec with beneficial effect on the haematological profile. HU may provide an effective approach to primary stroke prevention, particularly in Africa. Pediatr Blood Cancer 2015;62:1587–1591. © 2015 Wiley Periodicals, Inc.
From a Methodology Exercise to the Discovery of a Crisis: Serendipity in Field Research
Authors: Simard Magali , Laberge Danielle
Published: April 2015

Although serendipity is commonly encountered during research activities, it has not received as much attention as it deserves. Through a case study on a case study, which evolved from a methodology exercise into a rare case study of a project crisis, we mobilize the notions of serendipitous events and serendipity patterns to demonstrate how chance was cultivated using sagacity within the serendipity equation. Thereby, we contribute to a better understanding of the process of discovery through serendipitous creativity, especially in the dynamic and volatile project management research field where tensions between planned and unplanned are multiple.
Mixed Methods Use in Project Management Research
Authors: Cameron Roslyn , Sankaran Shankar , Scales Jeffery
Published: April 2015

Mixed methods research is increasingly being used in business and management disciplines, in spite of positivist traditions. The aim of the study is twofold: (1) to examine the types of mixed methods approaches being used, and (2) to determine the quality of the reporting of mixed methods studies published in the field of project management. A retrospective content analysis of articles from three ranked project management journals was undertaken for a sample period of 2004 to 2010. Our findings suggest the field of project management is in need of capacity building in relation to the good reporting of mixed methods studies.
Genealogical Ethnography: Process Thinking to Study the “Inside” of Projects
Authors: Vignehsa Kalpana
Published: April 2015

Genealogical ethnography is ethnography that acknowledges the impossibility of representing the “real” world and that demands an uncomfortable reflexivity, while still placing a premium on observations and detailed reportage. This theoretical case, along with a coherent methodological approach and its subsequent application to project-organization research, are presented in this article. Specifically, we learn how and why (1) using naturally occurring data; (2) a reporting style; and (3) problematizing confessional tales, together, build a formidable but simple toolkit for studying the “inside” of projects. As a result, the process-thinking capacity inherent to the established research paradigm of ethnography is stimulated.
Oxygen uptake kinetics and exercise capacity in children with cystic fibrosis
Authors: Fielding Jeremy , Brantley Lucy , Seigler Nichole , McKie Katie T. , Davison Gareth W. , Harris Ryan A
Published: April 2015

Exercise capacity, an objective measure of exercise intolerance, is known to predict quality of life and mortality in cystic fibrosis (CF). The mechanisms for exercise intolerance in patients with cystic fibrosis (CF), however, have yet to be fully elucidated. Accordingly, this study sought to investigate oxygen uptake kinetics and the impact of fat‐free mass (FFM) on exercise capacity in young patients with CF. 16 young patients with CF (age 13 ± 4 years; 10 female) and 15 matched controls (age 14 ± 3 years; nine female) participated. Pulmonary function and a maximal exercise test on a cycle ergometer using the Godfrey protocol were performed. Exercise capacity (VO2peak), VO2 response time (VO2RT), and functional VO2 gain (ΔVO2/ΔWR) were all determined. Lung function was the only demographic parameter significantly lower (P < 0.05) in CF compared to controls. Exercise capacity was lower in CF (P < 0.014) only when VO2 peak was normalized for FFM (43.5 ± 7.7 vs. 50.6 ± 7.4 ml/kg‐FFM/min) or expressed as % predicted (70.1 ± 14.3 vs. 85.4 ± 16.0%). The VO2RT was slower (36.1 ± 15.1 vs. 25.0 ± 12.4 sec; P = 0.03) and the ΔVO2/ΔWR slope was lower (8.4 ± 3 ml/min/watt vs. 10.1 ± 1.4 ml/min/watt; P = 0.02) in patients compared to controls, respectively. In conclusion, a delayed VO2 response time coupled with the lower functional VO2 gain (ΔVO2/ΔWR) suggest that young patients with CF have impairment in oxygen transport and oxygen utilization by the muscles. These data in addition to differences in VO2 peak normalized for FFM provide some insight that muscle mass and muscle metabolism contribute to exercise intolerance in CF. Pediatr Pulmonol. 2015; 50:647–654. © 2015 Wiley Periodicals, Inc.
First‐principles theory of acceptors in nitride semiconductors
Authors: Lyons John L. , Alkauskas Audrius , Janotti Anderson , Van de Walle Chris G.
Published: April 2015

Acceptor defects and impurities play a critical role in the performance of GaN‐based devices. Mg is the only acceptor impurity that gives rise to p‐type conductivity, while other acceptors (such as C impurities and defects) act as sources of compensation and trapping. From the point of view of theory, understanding the physics of acceptor species in GaN has long been a challenge. In the past, limitations of computational techniques made it difficult to quantitatively predict crucial quantities such as thermodynamic and optical transition levels. However, advances in first‐principles calculations, including the use of hybrid functionals in density functional theory, have led to a resurgence in efforts to understand properties of acceptors in nitrides. After briefly discussing advances in theoretical techniques, we review recent computational work on acceptor impurities in GaN and compare theoretical results with the available experimental data. We also present new hybrid density functional calculations on the transition levels of and its complexes with O and H impurities. The results indicate that donor impurities significantly lower transition levels, and that and complexes give rise to yellow luminescence. We also discuss the properties of acceptor impurities in AlN and InN.
Accelerated formation of the boron–oxygen complex in p‐type Czochralski silicon
Authors: Hamer Phillip , Hallam Brett , Abbott Malcolm , Wenham Stuart
Published: April 2015

This Letter reports on the acceleration of the rate of formation of the boron–oxygen defect in p‐type Czochralski silicon with illumination intensities in excess of 2.1 × 1017 photons/cm2/s. It is observed that increased light intensities greatly enhance the rate of defect formation, without increasing the saturation concentration of the defect. These results suggest a dependence of the defect formation rate upon the total majority carrier concentration. Finally, a method using temperatures up to 475 K and an illumination intensity of 1.68 × 1019 photons/cm2/s is shown to result in near‐complete defect formation within seconds. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
A robust estimation approach for uncertain systems with perturbed measurements
Authors: Bolajraf Mohamed , Ait Rami Mustapha
Published: April 2015

This paper deals with state estimation problem for uncertain continuous‐time systems. A numerical treatment is proposed for designing interval observers that ensures guaranteed upper and lower bounds on the estimated states. In order to take into account possible perturbations on the system and its outputs, a new type of interval observers is introduced. Such interval observers consist of two coupled general Luenberger‐type observers that involve dilatation functions. In addition, we provide an optimality criterion in order to find optimal interval observers that lead to tight interval error estimation. The proposed existence and optimality conditions are expressed in terms of linear programming. Also, some illustrative examples are given. Copyright © 2015 John Wiley & Sons, Ltd.
Future trends in broadband satellite communications: information centric networks and enabling technologies
Authors: Cola Tomaso De , Tarchi Daniele , Vanelli‐Coralli Alessandro
Published: April 2015

The ever‐increasing demand for multimedia services from fixed and mobile users has motivated the scientific community, industries, and standardization fora to rethink the communication paradigm and the protocol architectures, resulting in an overall revolution of the Internet technologies. As satellite will play a pivotal role in this picture to exploit its broadcast and broadband capabilities; technical challenges come up in the integration of satellite and terrestrial networks. New paradigms based on the recent Future Internet studies findings have to be also applied to the satellite communications domain, with consequent implications on the design of the physical layer, in order for the satellite capacity to accommodate all of the offered services. This paper explores the various challenges arising during this process and draws a new concept of broadband satellite systems, tailored to the needs of fixed and mobile users. Copyright © 2015 John Wiley & Sons, Ltd.
Sandwiched Electrochemiluminescent Peptide Biosensor for the Detection of Prognostic Indicator in Early‐Stage Cancer Based on Hollow, Magnetic, and Self‐Enhanced Nanosheets
Authors: Wang Haijun , Yuan Yali , Chai Yaqin , Yuan Ruo
Published: April 2015

Currently, peptide‐based protein‐recognition has been recognized as an effective and promising approach for protein assays. However, sandwiched peptide‐based biosensor with high sensitivity and low background has not been proposed before. Herein, a sandwiched electrochemiluminescence (ECL) peptide‐based biosensor is constructed for Cyclin A2 (CA2), a prognostic indicator in early stage of multiple cancers, based on nanosheets with hollow, magnetic, and ECL self‐enhanced properties. First, hollow and magnetic manganese oxide nanocrystals (H‐Mn3O4) are synthesized using triblock copolymeric micelles with core–shell–corona architecture as templates. Then, polyethyleneimine (PEI) and the composite of platinum nanoparticles and tris (4,4′‐dicarboxylicacid‐2,2′‐bipyridyl) ruthenium (II) (PtNPs–Ru) are immobilized on H‐Mn3O4 to form H‐Mn3O4–PEI–PtNPs–Ru nanocomposite, in which PEI as coreactant can effectively enhance the luminous efficiency and PtNPs as nanochannels can greatly accelerate the electron transfer. Finally, due to the coordination between Eu3+ and carboxyl, the obtained H‐Mn3O4–PEI–PtNPs–Ru aggregates locally to form sheet‐like nanostructures ((H‐Mn3O4–PEI–PtNPs–Ru)n–Eu3+), by which the luminous efficiency is further increased. Based on the nanosheets and two designed peptides, a sandwiched ECL biosensor, using palladium nanocages synthesized through galvanic replacement reaction as substrate, is proposed for CA2 with a linear range from 0.001 to 100 ng mL−1 and a detection limit of 0.3 pg mL−1.
“It's Like Being in Church and Being on a Field Trip:” The Date Versus Party Situation in College Students' Accounts of Hooking Up
Authors: Reid Julie A. , Webber Gretchen R. , Elliott Sinikka
Published: April 2015

This article examines the importance of setting as a factor shaping college students' dating and sexual behavior using a Goffmanian framework to explore how U.S. students interpret a vignette describing a casual heterosexual encounter at a party followed by a sexless dinner date. Rather than simply follow generalized cultural scripts, students indicate that college heterosexual encounters are guided by standardized patterns of behaviors based on the distinct settings and roles associated with each situation. Students view sexual behavior as appropriate to being a partygoer but unsuitable to being on a date. As such, hooking up with a stranger at a party can be more appropriate than having sex with the same person on a first date.
Kalmen estimator as a robust solution for output power maximization of wave energy converter
Authors: Kassem Ahmed M. , Besheer Ahmad H. , Atawi Ibrahem E.
Published: April 2015

In this paper, the application of linear quadratic Gaussian (LQG) control for a buoy‐type point absorber of a wave energy converter (PA‐WEC) system is investigated. The proposed wave energy conversion is considered as a two‐body system, which is taut‐anchored to the sea floor using three cables. The main goal of this study is to extract the maximum available power from the ocean wave. This is accomplished via determining the optimal value of the force exerted on the power take‐off (PTO) system taking in account the physical constraints on the position and velocity. First, the reduced nonlinear dynamical model of the WEC system is obtained. The nonlinearity in the mooring force is replaced by a linear law to yield the state space linear model of the system. Then, the standard Kalman filter technique is employed to estimate the full states of the system. Based on the LQG control approach, the optimal PTO force is computed at which the maximum output power can be easily harvested. The computational burden is minimized to a great extent by computing the optimal state feedback gains and the Kalman state space model offline. The feasibility of the proposed control approach in extracting the optimal power of the ocean wave is validated via the simulation example even under different values of the mooring constant and without violating the system limitation. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Internationalization Strategies of Business Schools: How Flat Is the World?
Authors: Guillotin Bertrand , Mangematin Vincent
Published: April 2015

Business school strategy has become extremely complex, especially regarding internationalization. Using different paths, experiencing failure and success, business schools have internationalized, attracting many of the international students who contributed $27 billion1 to the US economy in 2014. Some business schools are global, training global managers, while others serve national markets. How do business schools strategize about internationalization? Can we use existing models to explain this process? Are internationalization and globalization similar? Using a comparative analysis of six case studies in the United States and Europe, we found that the engine of internationalization influences its paths and outcomes. We contribute to international business (IB) research by discussing how business schools strategize their internationalization toward uniformity or diversity under isomorphic pressures from accreditation bodies (Association to Advance Collegiate Schools of Business [AACSB], 2011) and rankings. The so‐called Uppsala model should be extended to address three tensions: internationalization versus globalization, enacted dimensions of audiences, and respective risks of different internationalization pathways. © 2015 Wiley Periodicals, Inc.
Development and validation of a tool incorporating cervical length and quantitative fetal fibronectin to predict spontaneous preterm birth in asymptomatic high‐risk women
Authors: Kuhrt K. , Smout E. , Hezelgrave N. , Seed P. T. , Carter J. , Shennan A. H.
Published: April 2015

Objective

To develop a predictive tool for spontaneous preterm birth (sPTB) in asymptomatic high‐risk women that includes quantification of fetal fibronectin (fFN) along with cervical length (CL) measurement and other clinical factors.

Methods

Data were analyzed that had been collected prospectively from 1249 women at high risk for sPTB attending preterm surveillance clinics. Clinicians were blinded to quantitative measurements of fFN (qfFN), although they were aware of qualitative fFN results. Parametric survival models for sPTB, with time‐updated covariates, were developed and the best was selected using the Akaike and Bayesian information criteria. The model was developed on the first 624 consecutive women and validated on the subsequent 625. Fractional polynomials were used to accommodate possible non‐linear effects of qfFN and CL. The estimated probability of delivery before 30, 34 or 37 weeks' gestation and within 2 or 4 weeks of testing was calculated for each patient and analyzed as a predictive test for the actual occurrence of each event. Predictive statistics were calculated to compare training and validation sets.

Results

The final model that was selected used a log‐normal survival curve with CL, √qfFN and previous sPTB/preterm prelabor rupture of membranes as predictors. Predictive statistics were similar for training and validation sets. Areas under the receiver–operating characteristics curves ranged from 0.77 to 0.99, indicating accurate prediction across all five delivery outcomes.

Conclusions

sPTB in high‐risk asymptomatic women can be predicted accurately using a model combining qfFN and CL, which supersedes the single‐threshold fFN test, demographic information and obstetric history. This algorithm has been incorporated into an App (QUiPP) for widespread use. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
High‐intensity focused ultrasound treatment of placenta accreta after vaginal delivery: a preliminary study
Authors: Bai Y. , Luo X. , Li Q. , Yin N. , Fu X. , Zhang H. , Qi H.
Published: April 2015

Objective

To evaluate the safety and efficiency of high‐intensity focused ultrasound (HIFU) in the treatment of placenta accreta after vaginal delivery.

Methods

Enrolled into this study between September 2011 and September 2013 were 12 patients who had been diagnosed with placenta accreta following vaginal delivery and who had stable vital signs. All patients were treated using an ultrasound‐guided HIFU treatment system. As indication of the effectiveness of the treatment we considered decreased vascular index on color Doppler imaging, decrease in size of residual placenta compared with pretreatment size on assessment by three‐dimensional ultrasound with Virtual Organ Computer‐aided Analysis, reduced signal intensity and degree of enhancement on magnetic resonance imaging and avoidance of hysterectomy following treatment. To assess the safety of HIFU treatment, we recorded side effects, hemorrhage, infection, sex steroid levels, return of menses and subsequent pregnancy. Patients were followed up in this preliminary study until December 2013.

Results

The 12 patients receiving HIFU treatment had an average postpartum hospital stay of 6.8 days and an average period of residual placental involution of 36.9 days. HIFU treatment did not apparently increase the risk of infection or hemorrhage and no patient required hysterectomy. In all patients menstruation recommenced after an average of 80.2 days, and sex steroid levels during the middle luteal phase of the second menstrual cycle were normal. Two patients became pregnant again during the follow‐up period.

Conclusion

This preliminary study suggests that ultrasound‐guided HIFU is a safe and effective non‐invasive method to treat placenta accreta patients after vaginal delivery who have stable vital signs and desire to preserve fertility. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
Vakuumkomponenten für UHV und XHV aus Aluminium
Authors: Bergner Ute , Wolfgramm Stephan , Gottschall Sophie , Worsch Christian , Flämmich Michael
Published: April 2015

Im ersten Teil des Beitrags wurde gezeigt, dass moderne Aluminiumlegierungen über Festigkeiten verfügen, die zur Herstellung von Alu‐CF‐Flanschen für vielfache Dichtzyklen geeignet sind. Dabei ist es wichtig, dass sowohl beim Herstellungsprozess von Bauteilen als auch später im Einsatz kritische Grenztemperaturen nicht überschritten werden, welche die Festigkeit des Materials verringern. Der vorliegende Beitrag erklärt, wie reproduzierbare Prozessbedingungen beim Schweißen die Fertigung vakuumdichter Schweißnähte mit sauberer Wurzelbildung sicher stellen. Experimentell konnte nachgewiesen werden, dass unter Berücksichtigung der Materialeigenschaften bei der Konstruktion und mit speziellen Schweiß‐parametern sichergestellt werden kann, dass beim Schweißprozess im Schneidkantenbereich die kritischen Temperaturen nicht überschritten werden. Vergleichsmessungen an Aluminium‐ und Edelstahlkammern zeigen, dass mit Aluminium als Werkstoff in kürzerer Zeit und mit weniger Energieaufwand (niedrigere Ausheiztemperatur) im Vergleich zu Edelstahl UHV‐Bedingungen erreicht werden.
Schweißen mit dem Laserstrahl im Vakuum
Authors: Reisgen Uwe , Olschok Simon , Jakobs Stefan , Mücke Michael
Published: April 2015

In der Automobilindustrie werden Strahlschweißverfahren erfolgreich beim Fügen hochwertiger Bauteile eingesetzt. Hierbei stehen Komponenten des Antriebsstranges im Vordergrund. Insbesondere bei der Komponentenfertigung von Kupplungen, Zahnrad‐Wellen Verbindungen und Antriebswellen wird das Elektronenstrahlschweißen in kleinen Vakuum‐Taktkammern eingesetzt. Der Einsatz von leistungsstarken Festkörperlasern führt dagegen oft zu negativen Folgen, wie Verschmutzung durch Prozessemissionen oder eine stärkere Spritzerneigung. Durch den Einsatz des Laserstrahlschweißens im Vakuum können diese Begleiterscheinungen vermindert und gleichzeitig die Einschweißtiefe und die Nahtqualität gesteigert werden. Der Beitrag stellt erste Ergebnisse an Werkstücken aus der Automobilindustrie vor.
A Novel Turbomolecular Pump for R&D and Analytical Applications
Authors: Funke Ralf , Schnacke Ernst , Voss Gerhard
Published: April 2015

Turbomolecular pumps are high‐vacuum pumps which are used both for attaining very low ultimate pressures down to 10−10 mbar and for handling of high process gas flows up to inlet pressures of 10−3 mbar. Pumping speed and compression of these pumps essentially depend on the diameter of the inlet flange, on the design and rotational speed of the rotor and the Holweck stage respectively, and on gas type of the gases to be pumped.

The development of the novel TURBOVAC i/iX turbomolecular pump by Oerlikon Leybold Vacuum aimed at the realization of high pumping speeds and high compression ratios, especially for light gases. Both the rotor design and the bearing concept were particularly adapted to these requirements, also by using modern computer simulation tools.

This design concept has already proven its functionality in R&D and analytical applications.
Rezension
Authors: Wiesner Christian
Published: April 2015

Vacuum Technology in the Chemical Industry von Wolfgang Jorisch
On an inverse boundary problem for the heat equation when small heat conductivity defects are present in a material
Authors: Bouraoui M. , Asmi L. El , Khelifi A.
Published: April 2015

For the heat equation in a bounded domain we consider the inverse problem of identifying locations and certain properties of the shapes of small heat‐conducting inhomogeneities from dynamic boundary measurements on part of the boundary and for finite interval in time. The key ingredient is an asymptotic method based on appropriate averaging of the partial dynamic boundary measurements. Our approach is expected to lead to very effective computational identification algorithms.
An invariant‐free formulation of neo‐Hookean hyperelasticity
Authors: Kellermann David C. , Attard Mario M.
Published: April 2015

The principal focus of this paper is the formulation of a general approach to hyperelastic strain energy functions that does not rely on the use of scalar invariants of tensors. We call this an invariant‐free formulation of hyperelasticity. This essentially requires the conversion of the strain energy function from one of scalar products of scalar tensor invariants (all zeroth‐order) into one of quadruple contractions between fourth‐order tensors, thus preserving directional distinctions through to energy. We begin with an analysis of a range of hyperelastic properties in order to eliminate some non‐physical models. In the section after, we are left with the Simo and Pister model and the Compressible neo‐Hookean model, and decide on Simo and Pister's model for further study. Presented is a general form of invariant‐free hyperelasticity (the so‐called generalized strain energy function), and the fitting of the Simo and Pister model into that framework. The novelty of this invariant‐free formulation is threefold: first allowing the presentation of strain energy as a fourth‐order tensor that explicitly provides the origin of energy contributions from a possible 81 combinations through the simple exchange of the quadruple contraction operator with the Hadamard product; second is a new ability to seamlessly integrate micropolar effects into existing hyperelastic functions (a cursory look); and third is the direction‐preserving nature of the formulation, which satisfies the original charter of this work in providing a primer for the natural extension of advanced conventional hyperelastic functions from isotropic materials to anisotropic materials.
On the 3D Rayleigh wave field on an elastic half‐space subject to tangential surface loads
Authors: Ege Nihal , Erbaş Barış , Prikazchikov Danila A.
Published: April 2015

This study is concerned with analysis of the Rayleigh wave field in a 3D isotropic elastic half‐space subject to in‐plane surface loading. The approach relies on the slow time perturbation of the general representation for the Rayleigh wave eigensolutions in terms of harmonic functions. The resulting hyperbolic‐elliptic formulation allows decomposition of the original vector problem of 3D elasticity into a sequence of scalar Dirichlet and Neumann problems for the Laplace equation. The boundary conditions for these are specified through a 2D hyperbolic equation. An example of an impulse tangential load illustrates the efficiency of the derived asymptotic formulation, with the results expressed in terms of elementary functions.
Reframing Coalitions as Systems Interventions: A Network Study Exploring the Contribution of a Youth Violence Prevention Coalition to Broader System Capacity
Authors: Bess Kimberly D.
Published: April 2015

This longitudinal research conceptualizes community coalitions as events in local intervention systems (Hawe et al. in Am J Commun Psychol 43(3–4):267–276, 2009). It explores the potential contribution coalitions make, through the collaborative activities of their members, to the broader intervention systems in which they are embedded. Using social network analysis, it examines patterns of structural change in a network of 99 organizations focused on youth violence prevention (YVP) over a 5‐year period in which 30 of the 99 organizations were involved in a local YVP Coalition. Both longitudinal modeling and cross sectional analyses are used to examine change in system capacity—strong interorganizational networks—related to patterns of network density, centralization, and hierarchy. Somewhat surprisingly, the study found that capacity in the broader YVP Intervention System actually diminished during the 5‐year period of the coalition’s operation, though part of the system—the sub‐network that made up the YVP Coalition—was marginally strengthened. In this case, therefore, the evidence suggests that power and relational resources in the broader YVP Intervention System were redistributed. The article explores how the definition of capacity related to density and hierarchy may be contextually dependent. Implications for the role of coalitions in building system capacity are discussed.
MEDON MEETS A CYCLOPS?ODYSSEY22.310–80
Authors: Brelinski Tim
Published: April 2015

ὣς φάτο, τοῦ δ’ ἤκουσε Μέδων πεπνυμένα εἰδώς·πεπτηὼς γὰρ ἔκειτο ὑπὸ θρόνον, ἀμφὶ δὲ δέρμαἕστο βοὸς νεόδαρτον, ἀλύσκων κῆρα μέλαιναν.

So [Telemachus] spoke, and wise Medon heard him; for he had crouched down and was lying under a chair, and had wrapped around himself the newly flayed skin of an ox, avoiding grim death. (Od.22.361–3)

Immediately following the death of the suitors, near the end ofOdyssey22, we witness three scenes of supplication in quick succession. The first and unsuccessful suppliant is Leodes, the only suitor to survive, albeit briefly, theMnesterophonia. The second and third suppliants, respectively, are the bard Phemius and the herald Medon. Leodes pleads directly with Odysseus for his life, citing his previous conduct, that he had said or done no wrong to the women of the household. He also claims that he had actually attempted to keep the suitors' bad behaviour in check, an assertion corroborated by the narrator's own words (21.146–67). Odysseus rejects Leodes' plea and decapitates the prophet, putting a sudden end to his supplication (22.310–29). After this failed supplication, Phemius nervously considers either seeking refuge at the altar of Zeus Herkeios, located in Odysseus' courtyard, or directly supplicating Odysseus. He chooses the latter and also appeals to Telemachus as witness that he sang for the suitors only under compulsion (330–53). Telemachus intervenes and Medon, who overhears Telemachus' plea for mercy on behalf of Phemius and Medon, suddenly jumps up, throws off the ox hide under which he has escaped notice, grasps Telemachus by the knees, and asks the young man to vouch for and save him from Odysseus too (354–77).
A DITHYRAMB FOR AUGUSTUS: HORACE,ODES4.2
Authors: Hardie Alex
Published: April 2015

Odes4.2 ostensibly looks forward to two public events lying at some indeterminate point in the future, Augustus' return from campaign in Gaul, and a triumph over the Sygambri. The celebrations anticipated for these occasions frame the second half of the ode; but they do not supply its dramatic setting or timing, and the latter is evidently associated with the period following Augustus' departure for Gaul in summer 16b.c., or at any rate with a time when the Sygambri were felt still to present an armed threat. The dramatic date need not however be identical with the time of writing, and it should not be assumed thatOdes4.2 was composed in 16. Indeed, as will be seen (below, Section 6), it is most likely to be the retrospective product of a later period, around the time of Augustus' eventual return in July 13. On this view, the poem does not look forward to future events, but back to the time of Augustus' departure.
CICERO,LEG.1.6: ‘PLEASURABLE’ ANNALS?
Authors: Marincola John
Published: April 2015

quamobrem aggredere, quaesumus, et sume ad hanc rem tempus, quae est a nostris hominibus adhuc aut ignorata aut relicta. nam post annales pontificum maximorum, quibus nihil potest esse iucundius, si aut ad Fabium aut ad eum qui tibi semper in ore est, Catonem, aut ad Pisonem aut ad Fannium aut ad Vennonium uenias, quamquam ex his alius alio plus habet uirium, tamen quid tam exile quam isti omnes?

3iucundiusω:  iucundiusDavies: ieiuniusUrsinus: nudiusRob. Steph.

The manuscript readingiucundiushas had a few defenders, but nearly all editors have chosen to emend, and of the several emendations proposed, the favourite has been Orsini'sieiunius, adopted recently in Jonathan Powell's Oxford Classical Text, in Andrew Dyck's magisterial commentary, and in the new edition of the fragments of the Roman historians. Although the emendation can now be considered canonical, it is nevertheless worthwhile to restate and augment the arguments for retaining the manuscript reading.
ISAAC VOSSIUS, CATULLUS AND THE CODEX THUANEUS
Authors: Kiss Dániel
Published: April 2015

For Bernd Niebling and his colleagues at the Lesesaal Altes Buch of the Universitätsbibliothek München

While the earliest complete manuscripts of Catullus to survive today were written in the fourteenth century, it is well known that poem 62 already appears in an anthology from the ninth century, the Codex Thuaneus (Paris, Bibliothèque nationale de France, Parisinus lat. 8071). However, the Thuaneus may once have contained one more poem of Catullus. In his commentary on the poet, which appeared in 1684 but had been written decades earlier, the Dutch scholar Isaac Vossius makes the following comment on the last two lines of poem 11:

Praetereunte postquam Tactus aratro est] Vetustissimum exemplar Thuanæum in quo hoc Catulli carmen variorum epigrammatis subjungitur, legitfractus, nontactus. Et hoc probo, nisi malisstratus, nam in quibusdam libristractuslegebatur.

It is surprising to find a reference to a lost part of such a well-known manuscript in a source from the seventeenth century. One may well ask whether Vossius really read this poem in the Codex Thuaneus. Could he have seen this manuscript? Can he be relied on to report its contents truthfully? And could a part of the volume have been lost since the seventeenth century? I will argue that the answer to all these questions is yes, and that it is very likely that the Thuaneus once contained Catullus 11 as well as 62. I will set out the consequences of this for our understanding of Catullus' manuscript tradition. Next, I will discuss another ancient manuscript of Catullus that Vossius claims to have read, namely his ‘vetus liber Mediolanensis’. The article will close with an appendix on the history of the Thuaneus before it was studied by Vossius.
IDEALIZATION AND IRONY IN SALLUST'SJUGURTHA: THE NARRATOR'S DEPICTION OF ROME BEFORE 146 B.C.
Authors: Miller Jacob
Published: April 2015

An examination of the idealized image of Rome before 146b.c.constructed in theJugurtha(Jug.) reveals that despite the narrator's own stated opinions, his depiction of it is perverse and unhistorical. The narrator's value judgements are unappealing, his archaizing affected, his history plainly wrong: these are serious interpretative problems. Is this an attempt, as in the dialogues of Cicero, to re-educate the moral intuitions of his day by means of a fictitious past? Perhaps; but narratological analysis of the relevant sections suggests another solution, an extrapolation to the narratorial persona of the technique of ironic subversion used in the speeches. The key to understanding the depiction of Rome before 146 lies in the identification of political and historical discourse and the consequent extension to the latter of the factionalization characteristic of the former. The problematic aspects of the depiction of Rome before 146 empower the reader to articulate a critique of faction; the text needs to be surmounted to be understood.
EXEGI MONUMENTUM: EXILE, DEATH, IMMORTALITY AND MONUMENTALITY IN OVID,TRISTIA3.3
Authors: Ingleheart Jennifer
Published: April 2015

Tristia3.3 purports to be a ‘death-bed’ letter addressed by the sick poet to his wife in Rome (3.3.1–4), in which Ovid, banished from Rome on Augustus' orders, foresees his burial in Tomi as the ultimate form of exilic displacement (3.3.29–32). In order to avoid such a permanent form of exclusion from his homeland, Ovid issues instructions for his burial in the suburbs of Rome (3.3.65–76), dictating a four-line epitaph to be inscribed upon his tomb (3.3.73–6). However, despite the careful instructions he outlines for his burial and physical memorial, Ovid asserts:maiora libelli | et diuturna magis sunt monumenta mihi(‘my little books are a greater and more long-lasting monument for me’, 3.3.77–8), expressing his belief in his continued poetic afterlife. Scholars have seen this poem's concerns as above all literary, concentrating on Ovid's exploitation and development of elegiac and Augustan models which also treat the themes of death and poetic immortality. However, although Ovid's portrayal of what purports to be personal experience draws extensively upon earlier poetry, and, as we shall see, the poem gains much of its power from its engagement with the tradition that poetry alone can memorialize, previous studies have failed to analyse how Ovid consistently plays up the element that marks him out from the predecessors who had imagined their own deaths and poetic afterlives: that is, his status as an exile. Ovid's insistence on burial in his native land – from which he had been excluded in life – and his assertion of his poetic immortality in a poem which repeatedly stresses his exilic status, thus take on a markedly political angle, which had been absent or more muted in the models he exploits.
ARISTOTLE ON THE POLITICS OF MARRIAGE: ‘MARITAL RULE’ IN THEPOLITICS
Authors: Riesbeck David J.
Published: April 2015

In thePolitics, Aristotle maintains, contrary to his predecessors, that there is a distinctive mode of authority that husbands should exercise over their wives. He even coins a word for it: γαμιϰή, ‘the marital art’ or ‘marital rule’ (Pol. 1.3, 1253b8–10; 1.12, 1259a37–9). Marital rule is supposed to differ from the authority that fathers have over their children and from the kind of rule that citizens exercise over one another. Yet it is not clear whether there is any conceptual space between political and paternal rule for marital rule to occupy. Where fathers rule and children are ruled, citizens take turns ruling and being ruled. Husbands, however, either share their rule with their wives, or they do not. If they do not, then marital rule seems indistinct from paternal rule; if they do, then it seems indistinct from political rule. To add to the confusion, Aristotle says that husbands properly rule their wives politically, but without alternating in positions of ruling and being ruled. On its face, this idea seems flatly contradictory. Political rule just is shared, reciprocal rule, and so if the husband rules permanently and his wife is merely ruled, then his rule cannot be political. So Aristotle's own description of marital rule appears inconsistent, and in any case it is difficult to see how marital rule could have the distinctive character that he insists it does.
LUTATIUS CATULUS, CALLIMACHUS AND PLAUTUS'BACCHIDES
Authors: Heyworth S.J.
Published: April 2015

Aulus Gellius records an epigram of the Roman consul Q. Lutatius Catulus (Noctes Atticae19.9.14 = fr. 1 Blänsdorf/Courtney):Aufugit mi animus; credo, ut solet, ad Theotimumdeuenit. sic est, perfugium illud habet.quid si non interdixem, ne illunc fugitiuummitteret ad se intro, sed magis eiceret?ibimu' quaesitum. uerum ne ipsi teneamurformido. quid ago? da, Venu', consilium.
TWO TEXTUAL NOTES ON PINDAR'S EIGHTHNEMEAN
Authors: Lane Nicholas
Published: April 2015

πολλὰ γὰρ πολλᾷ λέλεκται, νεαρὰ δ᾽ ἐξευρόντα δόμεν βαϲάνῳ     20ἐϲ ἔλεγχον, ἅπαϲ κίνδυνοϲ· ὄψον δὲ λόγοι φθονεροῖϲιν,ἅπτεται δ᾽ ἐϲλῶν ἀεί, χειρόνεϲϲι δ᾽ οὐκ ἐρίζει.κεῖνοϲ καὶ Τελαμῶνοϲ δάψεν υἱόν, φαϲγάνῳ ἀμφικυλίϲαιϲ.21. ὄψον δὲ λόγοι BD : δὲ λόγοι om. Tricliniusφθονεροῖϲιν BD : φθόνῳ εἰϲίν Vauvilliers (vel potius φθονερῷ ᾽ιϲιν)I translate: ʻFor many things have been told in many ways, but to give novel things, when one has found them out, to the touchstone | For testing is pure danger: words are anamuse-boucheto the envious, | And it fastens on good men always, not taking issue with inferiors. | That too gnawed at Telamon's son, had him writhing on a sword.’ The difficulty presented by the transition in 22 from the plural ʻthe envious' to the singular subject ʻit' will be obvious. However, some commentators, including Mezger, Fennell and Bury, have assumed that φθόνοϲ can be supplied as the subject of ἅπτεται in 22 from φθονεροῖϲιν in 21, and the modern texts of Pindar – Bowra, Puech, Turyn and Snell–Maehler – do not mention the possibility of corruption in 21.
SOPHOCLES, SEDUCTION AND SHRIVELLING:ICHNEUTAIFR. 316 RADT
Authors: Thomas Oliver
Published: April 2015

Sophocles, fr. 316 comprises matching entries in Photius,Lex.p. 489 Porson and theSudaρ166, which are thought to derive from Pausanias the Atticist's dictionary. Erbse presents the following text (ρ5):

ῥικνοῦσθαι: τὸ διέλκεσθαι καὶ παντοδαπῶς διαστρέφεσθαι κατ' εἶδος. λέγεται δὲ καὶ τὸ καμπύλον γίγνεσθαι ἀσχημόνως καὶ κατὰ συνουσίαν καὶ ὄρχησιν, κάμπτοντα τὴν ὀσφῦν. Σοφοκλῆς Ἰχνευταῖς.
The BDS Campaign against Israel: Lessons from South Africa
Authors: Yi Joseph E. , Phillips Joe
Published: April 2015

The Boycott, Divestment, and Sanctions (BDS) campaign against Israel is animated by a pragmatic strain that views external sanctions as effective pressure against a small democratic state and by a moralistic Manichean strain that portrays Israelis as oppressors. Both strains hearken back to the earlier campaign against apartheid in South Africa. We argue that doing so misreads the lessons of South Africa. Sanctions may have contributed to ending apartheid, but they operated in conjunction with improved security and interpersonal trust among negotiators. Key contenders moved from a discourse of oppression to one that humanized one another as partners with legitimate concerns. These conditions are missing from the Israeli–Palestinian conflict. Both sides consider their security to be precarious and they are locked in competing narratives of victimization, which further erode mutual trust and security. Measures to improve the parties’ security and trust would contribute to mutual concessions and greater justification for sanctions if the Israeli government is intransigent.
Political Theory Simulations in the Classroom: Simulating John Locke’s Second Treatise of Government
Authors: Glasgow Derek
Published: April 2015

Political scientists frequently use in-class simulations as teaching tools. However, few such exercises have been developed to assist in teaching pre-modern political theories. This is unfortunate because simulations effectively promote active learning and excite students about course material. This article develops a new simulation to teach Locke'sSecond Treatise of Governmentin an introductory general education or political science course. Surveys of participants indicate that the Locke simulation promotes active learning, as well as understanding of course concepts, teamwork, and interest in the material.
Academic Mobility and Migration: What We Know and What We Do Not Know
Authors: Teichler Ulrich
Published: April 2015

Although internationalisation of the scientific world is a key issue in public attention and policy, the actual information base on migration and mobility of ‘teachers in higher education’, ‘scholars’, ‘academics’ or ‘researchers’ has remained weak. Most available statistics focus on ‘foreign’ students or ‘foreign’ scholars rather than persons mobile for purposes of learning and academic/research work, and provide information only on a single moment rather than on the life course of moving between countries. In recent years, some surveys of the ‘academic profession’ and ‘researchers’ have been undertaken primarily in economically advanced countries or especially in European countries that provide an overview on various modes, e.g. migration prior study, short-term student mobility and mobility for the whole degree programme, mobility in the phase of doctoral education and training, professional mobility in various stages of the professional career and finally shorter visits linked to academic and research work. All available information suggests that substantial differences exist by country and that no signs of convergence are visible. Moreover, surveys confirm that international experience is a frequently valuable asset of academic research careers but often is viewed as less beneficial than conventional wisdom suggests.