bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of polybenzoxazine precursors using thiols: Simultaneous thiol–ene and ring‐opening reactions
Authors: Beyazkilic Zeynep , Kahveci Muhammet U. , Aydogan Binnur , Kiskan Baris , Yagci Yusuf
Published: June 2012

A new class of polybenzoxazine precursors of combined molecular structure of benzoxazine in the open and ring form has been developed. Thermally curable benzoxazine networks were obtained by simultaneous photoinduced thiol‐ene and Catalytic Opening of the Lateral Benzoxazine Rings by Thiols (COLBERT). The thiol‐ene reactions were initiated by photolysis of a free radical photoinitiator, 2, 2‐dimethoxy‐2‐phenyl acetophenone (DMPA), and the competing COLBERT reaction was triggered by thiol compound, 1,2‐ethanedithiol, present in the reaction mixture. The extent of reactions was evaluated by conducting experiments both under UV irradiation and in dark using model benzoxazines. The precursor soft films (pre‐P(B‐ala‐DTE)) were prepared by irradiating solutions of diallyl functional benzoxazine (B‐ala), 1,2‐ethanedithiol and DMPA. The obtained pre‐P(B‐ala‐DTE) films were then cured through thermally activated ring opening reaction of remaining benzoxazine groups yielding a more rigid and tough film. Thermal and mechanical properties of the films were investigated by DSC, DMA and TGA and compared with a typical polybenzoxazine, P(B‐ala). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Photoresponsive water‐dispersible polyaniline nanoparticles through template synthesis with copolymer micelle containing coumarin groups
Authors: Luo Jing , Zhou Qun , Sun Jun , Jiang Jinqiang , Zhou Xin , Zhang Hongwu , Liu Xiaoya
Published: June 2012

A novel kind of photosensitive water‐dispersible polyaniline (PANI) nanoparticles was designed and prepared by template synthesis using a photo‐responsive vinyl‐coumarin (VM)/2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid (AMPS) copolymer micelle containing coumarin moieties. The resulting PANI nanoparticles exhibited reversible photo‐crosslinking and photo‐decrosslinking behavior similar to coumarin moiety upon irradiation with different UV light as verified by UV–vis absorption. In addition, photoinduced size change of the PANI nanoparticles after 365 nm UV light irradiation was successfully monitored by dynamic light scattering and transmission electron microscopy measurements, further confirming the photosensitivity of the obtained PANI nanoparticles by the incorporation of VM/AMPS copolymer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Acceptability to Patients of PhysioDirect Telephone Advice and Treatment Services: A Qualitative Investigation
Authors: Pearson Jennifer , Richardson Jane , Calnan Michael , Salisbury Chris , Foster Nadine
Published: June 2012

Introduction

In response to long patient waiting lists and problems of access, several primary care trusts have developed telephone assessment and treatment services led by physiotherapists (Foster et al., 2011). The PhysioDirect trial funded by the Medical Research Council is a randomized trial comparing this approach with usual physiotherapy care (Salisbury et al., 2009). This nested qualitative study aimed to explore and understand the key issues that determine patient acceptability of the PhysioDirect service.

Methods

Semi‐structured interviews were conducted with 57 purposively sampled patients with musculoskeletal problems participating in the randomized trial. The framework method (Ritchie and Lewis, 2003) was used to analyse the qualitative data.

Results

Acceptable features of the new PhysioDirect service were that patients considered it to be prompt, accessible and efficient. However, these benefits were often ‘traded off’ with less acceptable features. For example, patients perceived the PhysioDirect telephone assessment to be less personal than face‐to‐face contact, and some found it difficult to explain functional problems over the telephone. Patients who chose not to re‐contact the PhysioDirect service despite ongoing symptoms explained that this was because of reluctance to explain their problem again, fears about miscommunication and an inability to recall the advice from the first telephone call. Despite these reservations, most patients could foresee PhysioDirect within future physiotherapy services.

Conclusions

Overall, patients found the PhysioDirect service acceptable and thought it to be prompt, accessible and efficient, yet these benefits were traded off with several less acceptable features. To conclude, the qualitative evidence suggests that there are no major patient barriers to their utilization of the PhysioDirect service. Copyright © 2012 John Wiley & Sons, Ltd.
Anti‐diabetic Activity of Swertiamarin is due to an Active Metabolite, Gentianine, that Upregulates PPAR‐γ Gene Expression in 3T3‐L1 cells
Authors: Vaidya Hitesh , Goyal Ramesh K , Cheema Sukhinder Kaur
Published: June 2012

We have previously shown the anti‐diabetic effects of swertiamarin; however, pharmacokinetic analysis showed that swertiamarin had a plasma half‐life of 1.3 h. Gentianine is an active metabolite of swertiamarin that possesses a pharmacophoric moiety. The aim of this study was to explore the possibility whether the anti‐diabetic effect of swertiamarin is due to gentianine. Swertiamarin treatment had no significant effect on adipogenesis, or the mRNA expression of PPAR‐γ and GLUT‐4; however, there was a significant increase in the mRNA expression of adiponectin. On the other hand, treatment with gentianine significantly increased adipogenesis, which was associated with a significant increase in the mRNA expression of PPAR‐γ, GLUT‐4 and adiponectin. These findings suggest, for the first time, that the anti‐diabetic effect of swertiamarin is due to gentianine, an active metabolite of swertiamarin. Copyright © 2012 John Wiley & Sons, Ltd.
Nanostructuring and Microstructuring of Materials from a Single Agropolymer for Sustainable MAP Preservation of Fresh Food
Authors: Cagnon Thibaut , Guillaume Carole , Guillard Valérie , Gontard Nathalie
Published: June 2012

The main objective of the present work was to determine whether a single agropolymer [wheat gluten (WG)] could fit the modified atmosphere packaging (MAP) requirements of a range of six different fresh produce in key terms of oxygen permeation (PeO2) and CO2/O2 permselectivity (S) values. The required properties for optimal packaging of fresh fruits and vegetables were first evaluated using the Tailorpack MAP modelling software (UMR IATE, Montpellier, France) with packaging dimensions and respiratory and optimal atmosphere data as input parameters. Then, the modelled values obtained were compared with the properties of a range of WG composite films: monolayer self‐supported or multilayer at microscale or nanoscale, cast or thermoplasticised, with different formulations (percentage of plasticisers or nanofillers). The experimental gas transfer properties that could be covered by these materials ranged from 0.05 × 10−10 to 2.00 × 10−10 mol/m2 s Pa for PeO2 and up to 18.0 for S. These ranges are much larger than conventional plastics that exhibit PeO2 from 0.10 × 10−10 to 0.20 × 10−10 mol/m2 s Pa and S up to 4.5. It was demonstrated from a food‐requirements‐driven (Tailorpack modelling) and a multiscale film structuring (WG‐based composites) approaches, that transfer properties of WG‐based films would fit the requirements of the six selected fruits and vegetables better than conventional plastics. Copyright © 2012 John Wiley & Sons, Ltd.
Hash function‐based secret sharing scheme designs
Authors: Chum Chi Sing , Zhang Xiaowen
Published: June 2012

Secret sharing schemes create an effective method to safeguard a secret by dividing it among several participants. By using hash functions and the herding hashes technique, we first set up a (t + 1, n) threshold scheme that is perfect and ideal and then extend it to schemes for any general access structure. The schemes can be further set up as proactive or verifiable if necessary. The setup and recovery of the secret are efficient because of the fast calculation of the hash function. The proposed scheme is flexible because of the use of existing hash functions. Copyright © 2012 John Wiley & Sons, Ltd.
A learning progression for water in socio‐ecological systems
Authors: Gunckel Kristin L. , Covitt Beth A. , Salinas Ivan , Anderson Charles W.
Published: June 2012

Providing model‐based accounts (explanations and predictions) of water and substances in water moving through environmental systems is an important practice for environmental science literacy and necessary for citizens confronting global and local water quantity and quality issues. In this article we present a learning progression for water in environmental systems for students in elementary through high school grades. We investigated student accounts of water and substances in water moving through atmospheric, surface, and soil/groundwater systems, including human‐engineered components of these systems. Using an iterative process of model design, assessment, and interpretation, we identified four levels of achievement in student reasoning. Levels 1 and 2 force‐dynamic accounts explain movement of water as interactions between natural tendencies of water and countervailing powers. Level 3 incomplete school science accounts put events in order and trace water and substance along multiple pathways that include hidden and invisible components. Only Level 4 qualitative model‐based accounts include driving forces and constraining factors to explain or predict where water and substances in water move in given situations. The majority of high school students on average provide accounts between levels 2 and 3. We discuss the significance of these results for citizen participation in addressing common water issues. We end with suggestions for how the water learning progression can be used to inform changes to curricula, assessment, and instruction to support students in achieving level 4 performance. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 843–868, 2012
Perceived service quality in Ethiopian retail banks
Authors: Mersha Tigineh , Sriram Ven , Yeshanew Haile , Gebre Yonatan
Published: June 2012

This study uses the SERVQUAL method to assess perceived service quality in selected Ethiopian banks based on customer surveys conducted in three private and the largest public bank in Addis Ababa. For all banks, service expectations were not matched by perceived performance. While there were only a few differences in service expectations between public and private banks, private banks were perceived to be relatively better in delivering service. The findings also indicate that perceived service quality falls short of customer expectations in all the five dimensions of service quality—tangibles, reliability, responsiveness, assurance and empathy—with the largest perception‐expectation gap observed for the empathy dimension. As the banking sector becomes increasingly more competitive in Ethiopia, these findings can provide valuable insight to bank managers regarding the specific customer service issues that they need to address in their ongoing effort to attract and retain more customers. © 2012 Wiley Periodicals, Inc.
Is snow in the Alps receding or disappearing?
Authors: Beniston Martin
Published: June 2012

Snow in a populated and economically diverse region such as the Alps plays an important role in both natural environmental systems, (e.g., hydrology and vegetation), and a range of socio‐economic sectors (e.g., tourism or hydropower). Changes in snow amount and duration may impact upon these systems in various ways. The objective of this text is to assess whether the public perception that snow has been receding in recent decades in the European Alps is indeed upheld by observations of the behavior of the mountain snow‐pack in the last few decades. This article will show that, depending on location—and in particular according to altitude—the quantity of snow and the length of the snow season have indeed changed over the past century. While a major driving factor for this is clearly to be found in recent warming trends, other processes also contribute to the reduction in snow, such as the influence of the North Atlantic Oscillation on the variability of the mountain snow‐pack. This article ends with a short glimpse to the future, based on recent model studies that suggest that snow at low to medium elevations will indeed have all but disappeared by 2100. WIREs Clim Change 2012 doi: 10.1002/wcc.179

This article is categorized under:

Paleoclimates and Current Trends > Modern Climate Change
X‐ray emission from CsCl aqueous solutions when irradiated by intense femtosecond laser pulses and its application to time‐resolved XAFS measurement of I− in aqueous solution
Authors: Hatanaka Koji , Fukumura Hiroshi
Published: June 2012

This paper reviews X‐ray emission from electrolyte aqueous solutions when irradiated by intense femtosecond laser pulses in air. First, some examples of X‐ray emission spectra were shown when alkali halide aqueous solutions such as CsCl are used as samples. Dependence of X‐ray emission spectra on laser intensity, solute atomic numbers, and solute concentrations are discussed on the basis of multiphoton ionization, resonance absorption, and so on. Laser chirp effects on X‐ray emission were also discussed for understanding mechanisms occurring during a single laser pulse. X‐ray intensity increase up to 103–104 times with prepulse irradiation was also introduced, and the mechanism of X‐ray intensity increase was discussed from the viewpoint of laser ablation induced by the prepulse irradiation. Finally, preliminary results of time‐resolved X‐ray absorption fine spectroscopy using potassium iodide aqueous solution were presented. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis, Structure, and Supramolecular Chemistry of Three Azide Manganese Complexes with 2, 6‐Bis(benzimidazol‐2‐yl)pyridine
Authors: Wang Chuan‐Feng , Dai Guo‐Liang , Jin Zheng‐Neng , He Zhi‐Cai
Published: June 2012

Three azide complexes with the tridentate ligand 2, 6‐bis(benzimidazol‐2‐yl)pyridine (H2BBIP) were synthesized and their complicated supramolecular interactions were investigated with single‐crystal X‐ray diffraction. Interestingly, the complexes are assembled by bifurcated hydrogen bonding, double helical π–π stacking, or anion–π stacking interactions of the benzimidazole rings by tuning the reaction conditions (temperature, ratio, solvent). Complex 1 is a mononuclear compound, namely, Mn(H2BBIP)N3(CH3O)·CH3OH. In its 3D supramolecular network, the nitrogen atom of the azide anion is acting as hydrogen bonding bifurcated acceptor. Complex 2 is a dinuclear compound, namely, Mn2(H2BBIP)2(N3)2·(H2O)0.5. The dinuclear unit is connected by intramolecular π–π stacking interactions. Furthermore, double helical π–π stacking interactions in the benzimidazole rings are observed. Complex 3, Mn2(H2BBIP)2(N3)2·CH3OH, can be formulated as a pseudopolymorph of complex 2, which exhibits intramolecular π–π stacking interactions as well as anion–π interactions in the dinuclear unit.
Heterotic line bundle standard models
Authors: Anderson Lara B. , Gray James , Lukas Andre , Palti Eran
Published: June 2012

Abstract

In a previous publication, arXiv:1106.4804, we have found 200 models from heterotic Calabi-Yau compactifications with line bundles, which lead to standard models after taking appropriate quotients by a discrete symmetry and introducing Wilson lines. In this paper, we construct the resulting standard models explicitly, compute their spectrum including Higgs multiplets, and analyze some of their basic properties. After removing redundancies we find about 400 downstairs models, each with the precise matter spectrum of the supersymmetric standard model, with one, two or three pairs of Higgs doublets and no exotics of any kind. In addition to the standard model gauge group, up to four Green-Schwarz anomalous U(1) symmetries are present in these models, which constrain the llowed operators in the four-dimensional effective supergravity. The vector bosons associated to these anomalous U(1) symmetries are massive. We explicitly compute the spectrum of allowed operators for each model and present the results, together with the defining data of the models, in a database of standard models accessible here. Based on these results we analyze elementary phenomenological properties. For example, for about 200 models all dimension four and five proton decay violating operators are forbidden by the additional U(1) symmetries.
Prospective Evaluation of In‐hospital Mortality with the P‐POSSUM Scoring System in Patients Undergoing Major Digestive Surgery
Authors: Merad Féthi , Baron Gabriel , Pasquet Blandine , Hennet Henry , Kohlmann Gérard , Warlin Fred , Desrousseaux Bruno , Fingerhut Abe , Ravaud Philippe , Hay Jean‐Marie
Published: June 2012

Background

The P‐POSSUM score, the most well known of predictive scores for postoperative mortality, requires validation for population and setting.

Methods

Validation methods included discrimination (C‐index statistic), observed:expected (O:E) ratio, calibration with the Hosmer‐Lemeshow test, and subgroup analysis (emergency surgery, cancer, age, organs). The study included 3,881 multisite patients undergoing major digestive surgery in France.

Results

Discrimination via the receiver operating characteristic curve was good (C‐index = 0.87). The overall O:E ratio was 1 (95% confidence interval ([95 % CI]: 0.88–1.13), and therefore the quality of the surgical performance is within normal ranges. The O:E ratio, calculated by risk ranges, showed overestimation in the low risk range, especially in the 3 % to 6 % and 6 % to 10 % ranges. Calibration was poor (p < 0.001). The model deviated from the normal pattern of calibration, with mortality lower than expected in the high‐risk range. Subgroup analysis found reasonable to good discrimination of populations (C‐index ranging from 0.78 to 0.93 except for liver surgery [0.67]) while calibration of individuals remained poor (p < 0.001 to 0.02).

Conclusions

Good discrimination, as well as nonsignificant overall O:E values, makes P‐POSSUM a valuable tool when it is used for surgical audit to compare mortality between populations for major digestive surgery. Conversely, poor calibration (goodness‐of‐fit), especially in subgroup analysis, and underestimation or overestimation of O:E ratios considerably limits the value of P‐POSSUM for prediction of mortality in individuals. Therefore P‐POSSUM should not be used to predict outcomes for one particular patient.
Enhancing Teen Pregnancy Prevention in Local Communities: Capacity Building Using the Interactive Systems Framework
Authors: Duffy Jennifer L. , Prince Mary Severson , Johnson Erin E. , Alton Forrest L. , Flynn Shannon , Faye Amy Mattison , Padgett Polly Edwards , Rollison Chris , Becker Dana , Hinzey Angela L.
Published: June 2012

Getting To Outcomes (GTO), an innovative framework for planning, implementing, evaluating, and sustaining interventions has been shown to be effective in helping community‐based organizations (CBOs) introduce science‐based approaches into their prevention work. However, the Interactive Systems Framework (ISF) suggests that adopting innovations like GTO requires a significant amount of capacity building through training and technical assistance (T/TA). In this study, 11 CBOs and three schools in South Carolina entered into a 3 year program of intense and proactive T/TA based on the ISF to learn how to apply an adaptation of GTO (Promoting Science‐Based Approaches‐Getting To Outcomes, PSBA‐GTO) to their teen pregnancy prevention programs. Using semi‐structured interviews, the partnering organizations were assessed at three points in time, pre‐T/TA, 12 months, and post T/TA (30 months) for their performance of the steps of GTO in their work. The seven organizations which participated in T/TA until the end of the project received an average of 76 h of TA and 112 h of training per organization. Interview results showed increased performance of all 10 steps of PSBA‐GTO by these organizations when conducting their teen pregnancy programs. These results suggest targeted and proactive T/TA can successfully bridge the gap between research and practice by using a three part delivery system, as prescribed in the ISF, which relies on an intermediary prevention support system to ensure accurate and effective translation of research to the everyday work of community‐based practitioners.

Special Issue: Advances in Bridging Research and Practice Using the Interactive System Framework for Dissemination and Implementation; Guest Editors: Abraham Wandersman, Paul Flaspohler, Catherine A. Lesesne, Richard Puddy; Action Editor: Emilie Phillips Smith
For Colored Girls? Factors that Influence Teacher Recommendations into Advanced Courses for Black Girls
Authors: Campbell Shanyce L.
Published: June 2012

Given the lack of attention to Black girls’ participation in STEM related courses, it remains unclear why this group participates at lower rates in STEM courses later in their academic careers (Hyde et al. 2008; Tocci and Engelhard 1991; Catsambis 1994). The purpose of this paper is to examine the extent to which teachers influence Black girls’ opportunities along the math pipeline. The aim is to determine the role of Black girls’ cognitive and non-cognitive behaviors on teachers’ decisions to place them in advanced courses. Using nationally representative survey data, the findings indicate that Black girls’ confidence in their ability to master skills taught math reduced the odds teacher recommendations to advanced courses. Additionally, teachers’ expectations of the educational attainment of Black girls were related to the recommendation process. Overall, the findings suggest that subjective beliefs held by students and teachers critically influence Black girls’ persistence along the math pipeline.
Augusto Gansser (1910 – 2012)
Authors: Srikantia S.V.
Published: June 2012

We regret to announce the sad demise of Prof. Augusto Gansser, renowned Himalayan Geologist and Honorary Fellow of the Geological Society of India, on January 9, 2012 at Massagno, a municipality in the district of Lugano in the canton of Ticino in Switzerland, at the age of 101.
Distribution of Indus born Mica along Gulf of Kachchh Coast: Implications in Understanding Current Dynamics
Authors: Prizomwala S. P. , Shukla S. B. , Bhatt Nilesh
Published: June 2012

Indus is one of the major sources of sediments to the Gulf of Kachchh. Yet only its <63 micron fraction is studied in detail with regards to the offshore current dynamics. Hence here we present our study on characteristic signature of the Indus sediment load (i.e. mica minerals) in >63 micron size fraction along the coast of Gulf of Kachchh. The spatial distribution of mica minerals along the Gulf of Kachchh coast was studied which showed in general decreasing trend as we move along the northern and southern coast of the Gulf of Kachchh but, an increase in amount near the southern mouth at Okha. The study shows that the earlier proposed tidal barrier is ineffective in restricting movement of mica across the mouth of the gulf due to its characteristic transport mechanism. Also the presence of mudflats along the gulf of Kachchh coast plays a vital role as sediment receptors in the active sediment transport processes and mica minerals prove to be a promising simple tracer in studying the Indus born sediments in the region.
The C‐terminal region of NELL1 mediates osteoblastic cell adhesion through integrin α3β1
Authors: Hasebe Ai , Nakamura Yoko , Tashima Hiroki , Takahashi Kaneyoshi , Iijima Masumi , Yoshimoto Nobuo , Ting Kang , Kuroda Shun'ichi , Niimi Tomoaki
Published: June 2012

NELL1 is a secretory osteogenic protein containing several structural motifs that suggest that it functions as an extracellular matrix component. To determine the mechanisms underlying NELL1‐induced osteoblast differentiation, we examined the cell‐adhesive activity of NELL1 using a series of recombinant NELL1 proteins. We demonstrated that NELL1 promoted osteoblastic cell adhesion through at least three cell‐binding domains located in the C‐terminal region of NELL1. Adhesion of cells to NELL1 was strongly inhibited by function‐blocking antibodies against integrin α3 and β1 subunits, suggesting that osteoblastic cells adhered to NELL1 through integrin α3β1. Further, focal adhesion kinase activation is involved in NELL1 signaling.
Prevalence of hyperglycemia during pregnancy according to maternal age and pre‐pregnancy body mass index in Japan, 2007–2009
Authors: Morikawa Mamoru , Yamada Takashi , Yamada Takahiro , Sato Shoji , Cho Kazutoshi , Minakami Hisanori
Published: June 2012

Objective

To assess the prevalence of hyperglycemia according to maternal age and pre‐pregnancy body mass index (BMI) among Japanese women before introduction of the current diagnostic criteria.

Methods

In a retrospective study, data were analyzed from women with singleton pregnancies who were registered with the JSOG Successive Pregnancy Birth Registry System and who gave birth at 22 weeks of gestation or more between January 2007 and December 2009.

Results

Among 138 530 women, 3667 (2.6%) were diagnosed with hyperglycemia including gestational diabetes and diabetes mellitus. The prevalence of hyperglycemia increased with advancing maternal age and increasing BMI. Among women aged ≤ 24, 25–34, 35–39, and ≥ 40 years, the prevalence was 0.4%, 0.8%, 1.5%, and 4.0%, respectively, in lean women (BMI < 18.5); 1.0%, 1.6%, 2.3%, and 3.1%, respectively, in normal weight women (BMI 18.5–24.9); and 5.7%, 9.2%, 12.9%, and 15.2%, respectively, in obese women (BMI ≥ 25.0). Of the 1181 newborns with a birth weight of 4000 g or more, 1046 (88.6%) were born to women not diagnosed with hyperglycemia.

Conclusion

The results may reflect the baseline prevalence of hyperglycemia and macrosomic neonates (birth weight ≥ 4000 g) during the era of the old diagnostic criteria in Japan.
CONSTRUCTING AUTHOR AND AUTHORITY: GENERIC DISCOURSE IN CICERO’S DE LEGIBUS
Authors: DOLGANOV ANNA
Published: June 2012

Atticus: Lucus quidem ille et haec Arpinatium quercus agnoscitur, saepe a me lectus in Mario. Sin manet illa quercus, haec est profecto; etenim est sane uetus.

Qvintus: Manet uero, Attice noster, et semper manebit. Sata est enim ingenio; nullius autem agricolae cultu stirps tam diuturna quam poetae uersu seminari potest.

Atticus: Indeed I recognize that grove and this Arpinate oak, which I’ve often read about in the Marius. If that oak still stands, it must be this one; for old it certainly is.

Quintus: Of course it stands, my dear Atticus, and it will always stand, for it has been planted in the imagination. Indeed no farmer’s cultivation can produce a plant as long-lasting as that which is sown by the verse of a poet. De legibus 1.1

The image of the Marian oak begins De legibus with almost postmodern abruptness. This is in part due to the absence of an authorial preface, such as the long statement of purpose partially preserved in De re publica 1.1–14, which leaves De legibus without a chronological or situational frame of reference. The result is that the treatise begins in a particularly Platonic fashion, as the contemplation of an object in the natural landscape proceeds into a discussion of its symbolic meaning, setting up the dichotomy between perception and reality, ficta and vera, the past and its memory.
THE RAIN MIRACLE OF MARCUS AURELIUS: (RE-)CONSTRUCTION OF CONSENSUS
Authors: ISRAELOWICH IDO
Published: June 2012

Introduction

The reign of Marcus Aurelius, although he was acclaimed by ancient and modern commentators as an exemplary ruler, saw many calamities. Marcus was preoccupied with wars for the better part of his reign; the pestilence brought back to Rome from the east by Verus and the Roman army remained endemic in the city for many years to come, and the German wars from the late 160s well into the next decade posed great danger to Rome and caused great anxiety. In addition, a coup was executed. The usurper, Avidius Cassius, was the ruler of the Roman East for three months, enjoying support amongst the local population. After Verus’ death, the emperor embarked on war against the German tribes, but not before summoning priests and magicians from all over the world to help him, many of whom came from provinces far and wide. This attentiveness of Marcus Aurelius to religious issues (the representation of religious themes on his coins and monuments and his religious policy as a whole) introduced some changes to the Roman imperial tradition. Moreover his adaptation of policies that reflected new beliefs and the abandonment of old ones, was indicative of the political, social, and cultural developments during his reign. The desperation of the emperor is made most visible in the pages of Lucian’s Alexander.
IV From Greece to Rome
Authors: Lowe N.J.
Published: June 2012

The origins of Roman comedy are, in one sense, clear-cut: at the Ludi Romani or Roman Games of September 240, a Romanized Tarentine Greek known as Lucius Livius Andronicus, who at some point also translated the Odyssey into Latin, produced the first Latin translations of Greek plays on a Roman stage. This firm date, for which we have Cicero's friend Atticus to thank, marks the beginning of the establishment of a practice of translating classic Greek plays that would continue in both comedy and tragedy for at least a further century.
Coastal Management in Australia
Authors: Harvey Nick , Caton Brian
Published: June 2012

Coastal Management in Australia introduces the background to the various coastal management systems operating in Australia and illustrates these with 'real world' examples from the different states and territories.
Asymmetry in the current sheet and secondary magnetic flux ropes during guide field magnetic reconnection
Authors: Wang Rongsheng , Nakamura Rumi , Lu Quanming , Du Aimin , Zhang Tielong , Baumjohann Wolfgang , Khotyaintsev Yuri V. , Volwerk Martin , André Mats , Fujimoto M. , Nakamura T. K. M. , Fazakerley Andrew N. , Du Jian , Teh Waileong , Panov Evgeny V. , Zieger Bertalan , Pan Yongxin , Lu San
Published: June 2012

A magnetic reconnection event with a moderate guide field encountered by Cluster in the near‐Earth tail on 28 August 2002 is reported. The guide field points dawnward during this event. The quadrupolar structure of the Hall magnetic field within the ion diffusion region is distorted toward the northern hemisphere in the earthward part while toward the southern hemisphere tailward part of X‐line. Observations of current density and electron pitch angle distribution indicate that the distorted quadrupolar structure is formed due to a deformed Hall electron current system. Cluster crossed the ion diffusion region from south to north earthward of the X‐line. An electron density cavity is confirmed in the northern separatrix layer while a thin current layer (TCL) is measured in the southern separatrix layer. The TCL is formed due to electrons injected into the X‐line along the magnetic field. These observations are different from simulation results where the cavity is produced associated with inflow electrons along the southern separatrix while the strong current sheet appears with the outflow electron beam along the northern separatrix. The energy of the inflowing electron in the separatrix layer could extend up to 10 keV. Energetic electron fluxes up to 50 keV have a clear peak in the TCL. The length of the separatrix layer is estimated to be at least 65 c/ωpi. These observations suggest that electrons could be pre‐accelerated before they are ejected into the X‐line region along the separatrix. Multiple secondary flux ropes moving earthward are observed within the diffusion region. These secondary flux ropes are all identified earthward of the observed TCL. These observations further suggest there are numerous small scale structures within the ion diffusion region.
On the role of phyllosilicates on fault lubrication: Insight from micro‐ and nanostructural investigations on talc friction experiments
Authors: Boutareaud Sébastien , Hirose Takehiro , Andréani Muriel , Pec Matej , Calugaru Dan‐Gabriel , Boullier Anne‐Marie , Doan Mai‐Linh
Published: June 2012

Exposures of mature faults at the Earth's surface show that in the shallow crust some of co‐seismic slip occurs within a narrow phyllosilicate‐rich gouge material. Mechanical behavior of phyllosilicates sheared at seismic slip‐velocities remains a complex issue as suggested by the experimental and theoretical studies reported so far. Talc represents a simple case for common phyllosilicates in natural faults and therefore we chose talc as an analogue to better understand the mechanical behavior of clay‐rich mature crustal faults. We present a series of high‐velocity friction experiments conducted on talc at 1.31 m s−1 and normal stresses of 0.3–1.8 MPa for wet and dry conditions. At 1 MPa normal stress, both wet and dry experiments show a slip‐weakening behavior, however, with a higher decreasing rate in wet conditions. Dynamic shear stress evolves from a peak value of 0.24–0.52 MPa down to a residual state value of 0.08–0.18 MPa in wet conditions, and from a peak value of 0.46–1.17 MPa down to a residual state value of 0.12–0.62 MPa in dry conditions. Based on a detailed microstructural analysis down to the nanoscale, we propose thermal‐pressurization as a possible slip‐weakening mechanism for wet conditions. On the contrary, in dry conditions the long‐lasting weakening is interpreted to be due to a combination of i) progressive disappearance of geometrical incompatibilities, ii) solid lubrication of talc lamellae, and iii) powder lubrication by nanometric aggregates. We conclude that initial gouge humid conditions and inherited fabric from past sliding may have large influence on the slip‐weakening for subsequent slip.
Frequency dependence of mud volcano response to earthquakes
Authors: Rudolph Maxwell L. , Manga Michael
Published: June 2012

Distant earthquakes can trigger the eruption of mud volcanoes. We document the response of the Davis‐Schrimpf mud volcanoes, California, to two earthquakes and non‐response to four additional events. We show that the Davis‐Schrimpf mud volcanoes are more sensitive to long period seismic waves than to shorter period waves of the same amplitude. Our observations are consistent with models for dislodging bubbles and particles by time varying flows produced by seismic waves. Mobilizing trapped bubbles or particles increases permeability or fluid mobility, increasing discharge.
Inner plasma structure of the low‐latitude reconnection layer
Authors: Zhang Q.‐H. , Dunlop M. W. , Lockwood M. , Lavraud B. , Bogdanova Y. V. , Hasegawa H. , Yang H.‐G. , Liu R.‐Y. , Hu H.‐Q. , Zhang B.‐C. , Pu Z.‐Y. , Yang Z.‐W. , Wang J. , Taylor M. G. G. T. , Berchem J. , Constantinescu D. , Volwerk M. , Frey H. , Fazakerley A. N. , Shen C. , Shi J.‐K. , Sibeck D. , Escoubet P. , Wild J. A.
Published: June 2012

We report a clear transition through a reconnection layer at the low‐latitude magnetopause which shows a complete traversal across all reconnected field lines during northwestward interplanetary magnetic field (IMF) conditions. The associated plasma populations confirm details of the electron and ion mixing and the time history and acceleration through the current layer. This case has low magnetic shear with a strong guide field and the reconnection layer contains a single density depletion layer on the magnetosheath side which we suggest results from nearly field‐aligned magnetosheath flows. Within the reconnection boundary layer, there are two plasma boundaries, close to the inferred separatrices on the magnetosphere and magnetosheath sides (Ssp and Ssh) and two boundaries associated with the Alfvén waves (or Rotational Discontinuities, RDsp and RDsh). The data are consistent with these being launched from the reconnection site and the plasma distributions are well ordered and suggestive of the time elapsed since reconnection of the field lines observed. In each sub‐layer between the boundaries the plasma distribution is different and is centered around the current sheet, responsible for magnetosheath acceleration. We show evidence for a velocity dispersion effect in the electron anisotropy that is consistent with the time elapsed since reconnection. In addition, new evidence is presented for the occurrence of partial reflection of magnetosheath electrons at the magnetopause current layer.
A different interpretation of the annual and semiannual anomalies on the magnetic activity over the Earth
Authors: Azpilicueta Francisco , Brunini Claudio
Published: June 2012

The H component of the magnetic field measured at the terrestrial surface presents several periodic signals caused by changes in the ring current that flows within the terrestrial magnetosphere. One of the most important of them is associated to the phenomenon known as the Semiannual Anomaly which produces two significant minima during the equinoxes. This phenomenon is global, i.e., every observatory registers a similar effect independently of the hemisphere where it is located. A second important signal is due to the phenomenon known as the Annual Anomaly that produces significant different values for solstices, with a particular feature: the effect depends on the hemisphere where the observatory is located, with maximum during local summer. In spite of the time since their discoveries (more than a hundred years ago) the physical processes behind them are still open to discussion. In this work we present a new physical interpretation for the combined effects of both anomalies. The main concept developed is that along the year the shape of the magnetospheric cavities within which the ring current flows is deformed according to the geometric configuration between the solar wind and the magnetosphere.
On the turbulence generated by the potential surface waves
Authors: Benilov A. Y.
Published: June 2012

The turbulence (the random vortex motions) of the upper ocean is nourished by the energy and momentum of the surface waves (the potential motion). The statistical characteristics of the turbulence (turbulent kinetic energy, dissipation rate, and Reynolds stresses) depend on the state of the ocean surface waves. This paper discusses the possibilities of generating this turbulence using the vortex instability of the potential surface waves. The vortex component of fluctuations of velocity field and possibly the interaction between both the vortex and potential motions cause the vertical transport of the momentum. The Reynolds tensor is a linear function of the correlation tensor of vortex field. The initial small vortex perturbations always exist in the upper ocean because of the molecular viscosity influences, especially near the free surface, and the fluctuations of the seawater density. The horizontal inhomogeneities of the seawater density produce the vortex field even if the initial vorticity was zero and the initial flow was the potential flow. The evolution of the small initial vortex disturbances in the velocity field of potential linear surface waves is reduced to a coupled set of linear ordinary differential equations of the first order with periodic coefficients. The solution of this problem shows that the small initial vortex perturbations of potential linear surface waves always grow. The initial small vortex perturbations interacting with the potential surface wave produce the small‐scale turbulence (Novikov's turbulence) that finally causes the viscous dissipation of the potential surface wave. The wave‐induced turbulence can be considered as developed turbulence with a well distinguishable range of the turbulent wave numberskwhere turbulence obeys the Kolmogorov's self‐similarity law.
Non-linear alignment dynamics in suspensions of platelets under rotating magnetic fields
Authors: Erb Randall M. , Segmehl Jana , Charilaou Michalis , Löffler Jörg F. , Studart André R.
Published: June 2012

Under rotating magnetic fields, micron-sized platelets suspended in a fluid and decorated with magnetic nanoparticles are found to shift from a rotating motion to a biaxially-aligned state above a given frequency of the applied field.
Using iPad Technologies To Support Teaching and Learning in CSD
Authors: Friberg Jennifer C.
Published: June 2012

In a clinical project, 37 undergraduate students in a language disorders course with an academic service learning orientation reviewed iPad applications for use in language intervention activities. In this paper, I outline the process for implementing the project, as well as student perceptions of how their involvement in the project affected mastery of course-specific information.
A Wiki To Support Teaching the Course: Introduction to Communication Sciences and Disorders
Authors: Folkins John William , Behrman Alison , Self Trisha L. , Scudder Rosalind R.
Published: June 2012

We created a wiki to help those who either teach or plan to teach an Introduction to Communication Sciences and Disorders course. We hope the wiki will be a place to share ideas for improving course content and presentation. This includes innovative ideas that have not been tried, as well as past practices that both worked and didn’t work. It is also a place to comment on and give advice to others.
Many faces of stickiness in Hamiltonian systems
Authors: Bunimovich Leonid A. , Vela-Arevalo Luz V.
Published: June 2012

We discuss the phenomenon of stickiness in Hamiltonian systems. By visual examples of billiards, it is demonstrated that one must make a difference between internal (within chaotic sea(s)) and external (in vicinity of KAM tori) stickiness. Besides, there exist two types of KAM-islands, elliptic and parabolic ones, which demonstrate different abilities of stickiness.
Stable regimes for hard disks in a channel with twisting walls
Authors: Chernov N. , Korepanov A. , Simányi N.
Published: June 2012

We study a gas of N hard disks in a box with semi-periodic boundary conditions. The unperturbed gas is hyperbolic and ergodic (these facts are proved for N = 2 and expected to be true for all N≥2). We study various perturbations by twisting the outgoing velocity at collisions with the walls. We show that the dynamics tends to collapse to various stable regimes, however we define the perturbations, and however small they are.
Billiards: A singular perturbation limit of smooth Hamiltonian flows
Authors: Rom-Kedar V. , Turaev D.
Published: June 2012

Nonlinear multi-dimensional Hamiltonian systems that are not near integrable typically have mixed phase space and a plethora of instabilities. Hence, it is difficult to analyze them, to visualize them, or even to interpret their numerical simulations. We survey an emerging methodology for analyzing a class of such systems: Hamiltonians with steep potentials that limit to billiards.
Anisotropic shock sensitivity for β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine energetic material under compressive-shear loading from ReaxFF-lg reactive dynamics simulations
Authors: Zhou Tingting , Zybin Sergey V. , Liu Yi , Huang Fenglei , Goddard William A.
Published: June 2012

We report here the predictions on anisotropy of shock sensitivity and of chemical process initiation in single crystal β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (β-HMX) using compressive shear reactive dynamics (CS-RD) model with ReaxFF-lg reactive force field. Analysis of resolved shear stress induced by uniaxial compression along three shock directions normal to (110), (011), and (010) planes leads to identify eight slip systems as candidates for shear deformation. For each of the eight slip systems, non-equilibrium reactive dynamics simulations were carried out to determine thermal, mechanical, and chemical responses to shear deformation. Shock direction normal to (010) plane exhibits large shear stress barriers arising from steric hindrance between molecules of adjacent layers leading to local dramatic energy and temperature increases under shear flow that in turn accelerate chemical bond breaking and initial product formation processes, promoting further molecular decomposition and eventually transition to detonation. This suggests that single crystal β-HMX is sensitive to shocks in direction normal to (010) plane. Shock directions normal to (110) and (011) planes reveal significantly less steric hindrance, leading to more modest energy and temperature increases followed by slower chemical reaction initiation. Thus, shock directions normal to (110) and (011) planes are less sensitive than shock direction normal to (010) plane, which agree with interpretations from currently available plate impact experiments on HMX. This validation of CS-RD and ReaxFF for characterizing sensitivity of single crystal energetic materials indicates that these methods can be applied to study sensitivity for more complex polymer bonded explosives and solid composite propellants having complex microstructures, corrugated interfaces, as well as defects.
Mesoscale simulation of shock wave propagation in discrete Ni/Al powder mixtures
Authors: Austin Ryan A. , McDowell David L. , Benson David J.
Published: June 2012

A numerical model is developed to simulate shock wave propagation in discrete Ni/Al powder mixtures. The model is used to investigate the particle-level deformation, heating, and mixing of two distinct Ni/Al powders, as mixing intensity dictates whether or not shock ignition is achieved in these reactive material systems. The main innovations of this work are (1) use of a rate-dependent, dislocation-based model of particle flow stress in the shock simulations and (2) quantitative analysis of the Ni/Al interfaces that are formed during wave propagation. An experimental powder, which is composed of micron-scale spherical Ni and Al particles, is simulated to validate the numerical model. An additional powder, composed of smaller particles, is simulated to investigate the effects of particle size on constituent deformation and mixing under shock wave loading. The simulations indicate that a reduction in particle size leads to increased Ni/Al interface temperature and dislocation density, as well as increased stress-sensitivity of Ni/Al interface formation. Finally, it is shown that accounting for the rate-dependence of particle flow stress likely yields improved accuracy in predicted flow morphologies, especially at intermediate stress wave amplitudes.
A probability generating function method for stochastic reaction networks
Authors: Kim Pilwon , Lee Chang Hyeong
Published: June 2012

In this paper we present a probability generating function (PGF) approach for analyzing stochastic reaction networks. The master equation of the network can be converted to a partial differential equation for PGF. Using power series expansion of PGF and Padé approximation, we develop numerical schemes for finding probability distributions as well as first and second moments. We show numerical accuracy of the method by simulating chemical reaction examples such as a binding-unbinding reaction, an enzyme-substrate model, Goldbeter-Koshland ultrasensitive switch model, and G2/M transition model.
Effect of molybdenum on the structure formation of resorcinol–formaldehyde hydrogel studied by coherent x-ray scattering
Authors: Czakkel Orsolya , Nagy Balázs , Geissler Erik , László Krisztina
Published: June 2012

A detailed study on the effect of Mo on the gelation process of resorcinol–formaldehyde systems is presented. The evolution of the system was followed by x-ray photon correlation spectroscopy, which allows in situ investigation of the dynamics as well as of the structural evolution in non-equilibrium processes. The Mo was introduced into the system after a pre-polymerization period (PP), the effect of which was also examined. Our results show that the presence of Mo substantially modifies the gelation process by favoring the growth of large compact clusters with weak bonds between them. However, this effect can be reduced by increasing PP.