bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of a geostationary mission, geoCARB, to measure CO2, CH4 and CO column-averaged concentrations
Authors: Polonsky I. N. , O'Brien D.M. , Kumer J. B. , O'Dell C. W. , Team the geoCARB
Published: October 2013

Abstract. GeoCARB is a proposed instrument to measure column averaged concentrations of CO2, CH4 and CO from geostationary orbit using reflected sunlight in near-infrared absorption bands of the gases. The scanning options, spectral channels and noise characteristics of geoCARB and two descope options are described. The accuracy of concentrations from geoCARB data is investigated using end-to-end retrievals; spectra at the top of the atmosphere in the geoCARB bands are simulated with realistic trace gas profiles, meteorology, aerosol, cloud and surface properties, and then the concentrations of CO2, CH4 and CO are estimated from the spectra after addition of noise characteristic of geoCARB. The sensitivity of the algorithm to aerosol, the prior distributions assumed for the gases and the meteorology are investigated. The contiguous spatial sampling and fine temporal resolution that geoCARB could provide opens the possibility of monitoring localised sources such as power plants. Simulations of emissions from a power plant with a gaussian plume are conducted to assess the accuracy with which the emission strength may be recovered from geoCARB spectra. Scenarios for "clean" and "dirty" power plants are examined. It is found that a reliable estimate of the emission rate is possible, especially for power plants that have particulate filters, by averaging multiple snap-shots of the CO2 field surrounding the plant. The result holds even in the presence of partial cloud cover.
Anti-sunward high-speed jets in the subsolar magnetosheath
Authors: Plaschke F. , Hietala H. , Angelopoulos V.
Published: October 2013

Abstract. Using 2008–2011 data from the five Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft in Earth's subsolar magnetosheath, we study high-speed jets identified as intervals when the anti-sunward component of the dynamic pressure in the subsolar magnetosheath exceeds half of its upstream solar wind value. Based on our comprehensive data set of 2859 high-speed jets, we obtain the following statistical results on jet properties and favorable conditions: high-speed jets occur predominantly downstream of the quasi-parallel bow shock, i.e., when interplanetary magnetic field cone angles are low. Apart from that, jet occurrence is only very weakly dependent (if at all) on other upstream conditions or solar wind variability. Typical durations and recurrence times of high-speed jets are on the order of tens of seconds and a few minutes, respectively. Relative to the ambient magnetosheath, high-speed jets exhibit higher speed, density and magnetic field intensity, but lower and more isotropic temperatures. They are almost always super-Alfvénic, often even super-magnetosonic, and typically feature 6.5 times as much dynamic pressure and twice as much total pressure in anti-sunward direction as the surrounding plasma does. Consequently, they are likely to have significant effects on the magnetosphere and ionosphere if they impinge on the magnetopause.
Late Glacial-Holocene climatic transition record at the Argentinian Andean piedmont between 33–34° S
Authors: Mehl A. E. , Zárate M. A.
Published: October 2013

Abstract. The Arroyo La Estacada (~33°28' S, 69°02' W), eastern Andean piedmont of Argentina, cuts through an extensive piedmont aggradational unit composed of a dominant late Pleistocene–early Holocene (LP–EH) alluvial sequence including several paleosols. The arroyo sedimentary record exhibits a paleosol developed affecting the topmost part of likely Lateglacial aeolian deposits aggraded into a floodplain environment by the end of the late Pleistocene. The paleosol shows variable grade of development in the outcrops along the arroyo probably in relation to fluvial valley paleotopography. Organic matter humification, carbonate accumulation and redox processes were the dominant processes associated with paleosol formation. By the early Holocene, when the formation of the paleosol ended, alluvial aggradation renewed and a higher frequency of flooding events could have affected the arroyo's floodplain environment. A period of relative landscape stability in the Arroyo La Estacada basin is inferred from the paleosol developed by the LP–EH transition in response to a climatic amelioration in the Andes cordillera piedmont after the Late Glacial arid conditions. The renewal of early Holocene alluvial aggradation was probably influenced by the South American Monsoon and resulted in a change in the sedimentary dynamics of the arroyo. The analyzed Late Glacial-Holocene alluvial record of the Andean piedmont constitutes a suitable record of the LP–EH climatic transition at the extra Andean region of Argentina. It is in agreement with regional paleoclimatic evidence along the southern tip of the South American continent, where other sedimentary sequences record similar late Quaternary paleoenvironmental changes over both fluvial and interfluvial areas.
Effects of soil settlement and deformed geometry on a historical structure
Authors: Yardım Y. , Mustafaraj E.
Published: October 2013

Abstract. Protecting the historic character of a valued structure during the assessment and damage repair process is a very challenging task for many engineers. Heritage protection is complicated by a lack of design details and restrictions on sample extraction needed to obtain accurate material properties and limited studies on the restoration of certain types of historical structures. This study aims to assess the effects of soil settlement on a structure's stress concentrations and the value of laser scanning techniques on structure analysis in obtaining correct data of settlement vs. deformation. Terrestrial laser scanner (TLS) data are used to analyse the 500 yr-old historical structure of Naziresha's Mosque. The obtained TLS data allow an accurate definition of the imperfect geometry patterns lying on every side of the structure. The soil profile and general crack formation together with TLS measurement proves that the structure deformed toward the south façade, where a railway and motorway are also located. Stress concentration and mode period results have a considerable difference, which highlights earthquake vulnerability and failure mechanisms and changes the strategy of possible retrofitting.
Application of a hybrid approach in nonstationary flood frequency analysis – a Polish perspective
Authors: Kochanek K. , Strupczewski W. G. , Bogdanowicz E. , Feluch W. , Markiewicz I.
Published: October 2013

Abstract. The alleged changes in rivers' flow regime resulted in the surge in the methods of non-stationary flood frequency analysis (NFFA). The maximum likelihood method is said to produce big systematic errors in moments and quantiles resulting mainly from bad assumption of the model (model error) unless this model is the normal distribution. Since the estimators by the method of linear moments (L-moments) yield much lower model errors than those by the maximum likelihood, to improve the accuracy of the parameters and quantiles in non-stationary case, a new two-stage methodology of NFFA based on the concept of L-moments was developed. Despite taking advantage of the positive characteristics of L-moments, a new technique also allows to keep the calculations "distribution independent" as long as possible. These two stages consists in (1) least square estimation of trends in mean value and/or in standard deviation and "de-trendisation" of the time series and (2) estimation of parameters and quantiles by means of stationary sample with L-moments method and "re-trendisation" of quantiles. As a result time-dependent quantiles for a given time and return period can be calculated. The comparative results of Monte Carlo simulations confirmed the superiority of two-stage NFFA methodology over the classical maximum likelihood one. Further analysis of trends in GEV-parent-distributed generic time series by means of both NFFA methods revealed big differences between classical and two-stage estimators of trends got for the same data by the same model (GEV or Gumbel). Additionally, it turned out that the quantiles estimated by the methods of traditional stationary flood frequency analysis equal only to those non-stationary calculated for a strict middle of the time series. It proves that use of traditional stationary methods in conditions of variable regime is too much a simplification and leads to erroneous results. Therefore, when the phenomenon is non-stationary, so should be the methods used for its interpretation.
Ion motion in the current sheet with sheared magnetic field – Part 2: Non-adiabatic effects
Authors: Artemyev A. V. , Neishtadt A. I. , Zelenyi L. M.
Published: October 2013

Abstract. We investigate dynamics of charged particles in current sheets with the sheared magnetic field. In our previouspaper (Artemyev et al., 2013) we studied the particle motion in such magnetic field configurations on the basis of the quasi-adiabatic theory and conservation of the quasi-adiabatic invariant. In this paper we concentrate on violation of the adiabaticity due to jumps of this invariant and the corresponding effects of stochastization of a particle motion. We compare effects of geometrical and dynamical jumps, which occur due to the presence of the separatrix in the phase plane of charged particle motion. We show that due to the presence of the magnetic field shear, the average value of dynamical jumps is not equal to zero. This effect results in the decrease of the time interval necessary for stochastization of trapped particle motion. We investigate also the effect of the magnetic field shear on transient trajectories, which cross the current sheet boundaries. Presence of the magnetic field shear leads to the asymmetry of reflection and transition of particles in the current sheet. We discuss the possible influence of single-particle effects revealed in this paper on the current sheet structure and dynamics.
Lagrangian transport in a microtidal coastal area: the Bay of Palma, island of Mallorca, Spain
Authors: Hernández-Carrasco I. , López C. , Orfila A. , Hernández-García E.
Published: October 2013

Abstract. Coastal transport in the Bay of Palma, a small region in the island of Mallorca, Spain, is characterized in terms of Lagrangian descriptors. The data sets used for this study are the output for two months (one in autumn and one in summer) of a high resolution numerical model, ROMS (Regional Ocean Model System), forced atmospherically and with a spatial resolution of 300 m. The two months were selected because of their different wind regime, which is the main driver of the sea dynamics in this area. Finite-size Lyapunov exponents (FSLEs) were used to locate semi-persistent Lagrangian coherent structures (LCS) and to understand the different flow regimes in the bay. The different wind directions and regularity in the two months have a clear impact on the surface bay dynamics, whereas only topographic features appear clearly in the bottom structures. The fluid interchange between the bay and the open ocean was studied by computing particle trajectories and residence time (RT) maps. The escape rate of particles out of the bay is qualitatively different, with a 32% greater escape rate of particles to the ocean in October than in July, owing to the different geometric characteristics of the flow. We show that LCSs separate regions with different transport properties by displaying spatial distributions of residence times on synoptic Lagrangian maps together with the location of the LCSs. Correlations between the time-dependent behavior of FSLE and RT are also investigated, showing a negative dependence when the stirring characterized by FSLE values moves particles in the direction of escape.
Western Pennsylvania-West Virginia Chapter of ACRL Commemorates Its History
Authors: Fredette Hilary , Barnett John , Blake Linda
Published: October 2013

At its spring 2013 conference, the Western Pennsylvania-West Virginia Chapter of the Association of College and Research Libraries (WPWVC ACRL) celebrated its 60th anniversary. The organization will also commemorate its 25th anniversary this year.
First PA Forward Information Literacy Summit
Authors: Neyer Linda
Published: October 2013

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Noteworthy: News Briefs from Pennsylvania Libraries
Authors: Barnett John
Published: October 2013

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Una mirada de la tutoría y el asesoramiento en el marco del Proyecto Montegrande
Authors: González Paola
Published: October 2013

El siguiente artículo lleva a cabo una revisión del trabajo del asesor educacional en el marco de la implementación del Proyecto Montegrande que impulsara el Ministerio de Educación como parte de las políticas de la Reforma Educacional en cuanto a la innovación y mejoramiento educativo durante el periodo 1997-2004. Se centra específicamente el análisis en la experiencia profesional del rol del asesor-tutor y los elementos teóricos, políticos y técnicos a considerar que incidieron en su labor y en el desarrollo de la estrategia interna de asesoramiento ministerial para estos liceos de anticipación.
Market Potential, Industrial Density and Revenue of Tourism Firms in China
Authors: Yang Yong
Published: October 2013

China is a major source of empirical observations with which to test different hypotheses relative to tourism research. In this paper, the author constructs a spatial model of tourism industry development and, considering spatial distance, uses Chinese tourism panel data to analyse the relationship between market potential, industrial density and the revenue of tourism firms. The study provides evidence that tourism market potential and agglomeration density are statistically significant and quantitatively important in explaining the revenue of tourism firms. This finding is robust, controlling for input factor density and endogeneity using instrument variables. Tourism market potential is found to matter through the mechanisms promoted by new economic geography theory. The estimated coefficients are consistent with plausible values for the predication of the model.
The Potential of Local KIBS Companies as a Determinant of Tourism Development in Krakow
Authors: Borodako Krzysztof , Berbeka Jadwiga , Rudnicki Michał
Published: October 2013

Destinations compete with each other using production factors generated internally or purchased externally. One factor usually outsourced is knowledge. Key providers of this asset are firms offering knowledge-intensive business services (KIBS); the strength of Krakow's position on the tourism market could be significantly influenced by KIBS firms. The objective of this study is to analyse the relationship between the development in Krakow of tourism, on the one hand, and KIBS firms, on the other. A review of the literature confirmed that KIBS are a determinant of the city's potential (including that of the tourism sector). Analysis of tourism supply, represented by the growth dynamic in the hotel segment, shows a higher increase than in tourism movement, but significantly lower than in many other KIBS subsectors. In this context the competitiveness and innovation of Krakow's tourism companies could be boosted by knowledge and expertise from KIBS companies.
Achieving Balanced Regional Development in China: Is Domestic or International Tourism More Efficacious?
Authors: Goh Carey , Li Hengyun , Zhang Qiu
Published: October 2013

Many developing countries are now suffering from rather large regional development gaps. Can tourism promote balanced regional development (BRD) and so narrow such gaps? This study empirically examines and compares the impact of both international and domestic tourism on China's regional development using the Gini coefficient method and the Granger causality test. The results indicate that the spatial distribution of the total tourism industry is more unbalanced than that of the regional economy. However, the imbalance in the spatial distribution is decreasing more rapidly than the imbalance in the regional economy. The Gini coefficient decomposition analysis shows that declining tourism spatial distribution imbalances are mainly and increasingly caused by domestic tourism. Granger causality tests show that tourism development will promote BRD through domestic tourism rather than international tourism. Finally, the authors draw out the policy implications for China's tourism industry and BRD.
Subempleo laboral en las industrias productivas de Nicaragua
Authors: Mendoza Tijerino Francisco , Altamirano Montoya Álvaro
Published: October 2013

En el presente artículo se analiza el subempleo utilizando información de laúltima Encuesta Continua de Hogares 2010, publicada por el Instituto Nacional de Información del Desarrollo (INIDE) de Nicaragua. Se busca identificar las industrias que presenten más problemas de subempleo, tomando en cuenta que los individuos que se encuentren subempleados son individuos que están inconformes e insatisfechos al momento de realizar las labores productivas. Se encuentra que, en relación a las demás industrias del país, la industria de la construcción es la que presenta mayores probabilidades de contar con empleados con deseos de trabajar más y no poder hacerlo.
Textrode-enabled transthoracic electrical bioimpedance measurements – towards wearable applications of impedance cardiography
Authors: Marquez J.C. , Rempfler M. , Seoane F. , Lindecrantz K.
Published: October 2013

During the last decades the use of electrical bioimpedance (EBI) in the medical field has been the subject of extensive research, as an affordable, harmless and non-invasive technology. In some specific applications, such as body composition assessment where EBI has proven a good degree of effectiveness and reliability, the use of textile electrodes and measurement garments have shown good performance and reproducible results. Impedance cardiography (ICG) is a modality of EBI that can benefit from the implementation and use of wearable sensors. ICG is based on continuous impedance measurements of a longitudinal segment across the thorax taken at a single frequency. The need for a specific electrode placement on the thorax and neck can be easily ensured with the use of a garment with embedded textile electrodes, also known as “textrodes.” The first step towards the implementation of garment-based ICG is to determine the quality of ICG measurements with textile sensors to allow estimation of fundamental ICG parameters. In this work, the measurement performance of a 2-belt set with incorporated textrodes for thorax and neck is compared against ICG measurements obtained with Ag/AgCl electrodes. The analysis is based on the quality of the fundamental ICG signals (ΔZ, dZ/dt and ECG), systolic time intervals and other ICG parameters. The results indicate the feasibility of using textrodes for ICG measurements with consistent measurements and relatively low data dispersion. Thus, enabling the development of measuring garments for ICG measurements.
Estimation of Upper Limb Joint Angle Using Surface EMG Signal
Authors: Aung Yee Mon , Al-Jumaily Adel
Published: October 2013

In the development of robot-assisted rehabilitation systems for upper limb rehabilitation therapy, human electromyogram (EMG) is widely used due to its ability to detect the user intended motion. EMG is one kind of biological signal that can be recorded to evaluate the performance of skeletal muscles by means of a sensor electrode. Based on recorded EMG signals, user intended motion could be extracted via estimation of joint torque, force or angle. Therefore, this estimation becomes one of the most important factors to achieve accurate user intended motion. In this paper, an upper limb joint angle estimation methodology is proposed. A back propagation neural network (BPNN) is developed to estimate the shoulder and elbow joint angles from the recorded EMG signals. A Virtual Human Model (VHM) is also developed and integrated with BPNN to perform the simulation of the estimated angle. The relationships between sEMG signals and upper limb movements are observed in this paper. The effectiveness of our developments is evaluated with four healthy subjects and a VHM simulation. The results show that the methodology can be used in the estimation of joint angles based on EMG.
Dynamic Characterization and Interaction Control of the CBM-Motus Robot for Upper-Limb Rehabilitation
Authors: Zollo Loredana , Salerno Antonino , Vespignani Massimo , Accoto Dino , Passalacqua Massimiliano , Guglielmelli Eugenio
Published: October 2013

This paper presents dynamic characterization and control of an upper-limb rehabilitation machine aimed at improving robot performance in the interaction with the patient. An integrated approach between mechanics and control is the key issue of the paper for the development of a robotic machine with desirable dynamic properties. Robot inertial and acceleration properties are studied in the workspace via a graphical representation based on ellipses. Robot friction is experimentally retrieved by means of a parametric identification procedure. A current-based impedance control is developed in order to compensate for friction and enhance control performance in the interaction with the patient by means of force feedback, without increasing system inertia. To this end, servo-amplifier motor currents are monitored to provide force feedback in the interaction, thus avoiding the need for force sensors mounted at the robot end-effector. Current-based impedance control is implemented on the robot; experimental results in free space as well as in constrained space are provided.
Dynamics Analysis of Fluid-Structure Interaction for a Biologically-Inspired Biped Robot Running on Water
Authors: Xu Linsen , Cao Kai , Wei Xianming , Shi Yungao
Published: October 2013

A kinematics analysis of a biologically-inspired biped robot is carried out, and the trajectory of the robot foot is understood. For calculating the pressure distribution across a robot foot before touching the surface of water, the compression flow of air and the depression motion of the water surface are considered. The pressure model after touching the water surface has been built according to the theory of rigid body planar motion. The multi-material ALE algorithm is applied to emulate the course of the foot slapping water. The simulation results indicate that the model of the bionic robot can satisfy the water-running function. The real prototype of the robot is manufactured to test its function of running on water. When the biped robot is running on water, the average force generated by the propulsion mechanism is about 1.3N. The experimental results show that the propulsion system can satisfy the requirement of biped robot running on water.
Prioritizing the Factor Weights Affecting Tourism Performance by FAHP
Authors: Do Quang Hung , Chen Jeng Fung
Published: October 2013

The allocation of limited resources to effectively promote tourism is one of the most important issues in the tourism industry, especially in tough economic times. This paper seeks to investigate the relative importance of the key factors affecting tourism performance by applying the fuzzy analytic hierarchy process (FAHP) method. Specifically, the paper identifies the factors and sub-factors of the hierarchical structure from the literature relating to tourism performance. The framework based on the AHP method is then proposed to determine the relative weights of the factors and sub-factors in contributing to tourism performance. An application case related to the Vietnamese context is used to illustrate the proposed framework. The results of this study consolidated the tourism theory and suggested recommendations and solutions for the Vietnamese tourism industry. The proposed framework could be used by a group of decision-makers to achieve a consensus, as well as deal with uncertainty in the decision-making process. The findings of the study may serve as a tool for assistance for planners in improving the efficiency of tourism performance.
ELF, ACA:DEMIC WRITING, AND THE SEMANTICIZATION OF THOUGHT
Authors: Grundy Peter
Published: October 2013

This paper takes the view that varieties of writing represent agreed ways of mediating content that are recognized by discourse communities such as the academy who constitute their expectable readerships. These mediations make use of language-specifi c default affordances that are not only syntactic but also pragmatic and represent thinking for speaking categories (Slobin 1996) which, I argue, have greater explanatory power than the more abstract concept of virtual English (Seidlhofer 2011). In this context, I make a few preliminary comments on what appear to be the pragmatic affordances identifi able in parallel English texts generated by two native Chinese and a native English student writer faced with the same academic task, and make some consequent observations about teaching academic writing.
I’M BY DEFAULT POLITE – POLITENESS AND POSITIONING IN MMORPGS
Authors: Kramer Birgit
Published: October 2013

MMORPGs (Massively Multiplayer Online Role-playing Games) like World of Warcraft® require gamers to communicate in English regardless of their language competence in it. Therefore, English becomes the lingua franca of many gamers. Furthermore, gamers have to communicate effi ciently with one another in high stress situations causing another linguistic challenge. These conditions do not lead to the assumption that politeness is of any relevance in MMORPGs but rather that these games are hostile and impolite environments. A survey investigating the language usage of gamers, including a questionnaire and a selfcompiled corpus, sheds light on the language usage and politeness of gamers. This survey asks how and why gamers coming from different language backgrounds using ELF in MMORPGs utilize politeness to position themselves.
MITIGATED DISAGREEMENT IN LEARNER DISCUSSION FORA: A FACILITATOR’S PERSPECTIVE
Authors: Szczyrbak Magdalena
Published: October 2013

The aim of this paper is to focus on one aspect of English learners’ pragmatic competence which can be effi ciently developed through threaded discussions, i.e. on the dispreferred speech act of disagreement. The author shares her experience of using online discussion fora in Practical English classes designed for third-year students. She comments on the linguistic resources used by the students to express mitigated disagreement and, further, she discusses the role of the instructor in facilitating interactional coherence. The author reaches the conclusion that asynchronous discussion fora can be useful in developing English learners’ pragmatic strategies, provided that online collaboration is carefully and wisely planned, and encouraged by a dedicated and enthusiastic instructor.
LEXICAL BUNDLES INDICATING AUTHORIAL PRESENCE: A CROSS-CULTURAL ANALYSIS OF NOVICE CZECH AND GERMAN WRITERS’ ACADEMIC DISCOURSE
Authors: Dontcheva-Navratilova Olga
Published: October 2013

With the widespread use of English as the lingua franca of academia, there is a growing need of research into how non-native speakers striving to be socialized in target academic discourse communities deal with variation in meaning and organization of academic texts across fi elds, languages and cultures. An important indicator of competent linguistic production is the mastering of the register- and genre-specifi c formulaic expressions termed lexical bundles, which are defi ned as sequences of three or more words with frequent co-occurrence in a particular context (Biber et al. 1999). While recent studies have addressed disciplinary and novice-expert differences in the use of lexical bundles, cross-cultural variation in bundle use remains underexplored. This paper investigates lexical bundles indicating authorial presence in a specialized corpus of Master’s degree theses from the fi elds of linguistics and methodology written by German and Czech university students. The aim of the study is to compare how novice Czech and German authors use lexical bundles indicating authorial presence, to consider whether and to what extent the novice writers have adapted their writing style to the conventions of Anglo- American academic writing, and to discuss the role of the L1 academic literacy tradition and instructions received in writing courses for the modelling of novice writers’ academic discourse. The analysis shows that the variety and frequency of interpersonal bundles in Czech and German novice writers’ discourse do not approximate to the standard of published academic texts in English. The fi ndings also indicate that while the considerable similarities in the way Czech and German novice writers use the target structures for constructing authorial presence refl ect their common roots in the Central European tradition of academic discourse, the divergences may be attributed to a difference in the degree of adaptation to Anglo-American writing conventions.
La trame augustinienne dans Qu’est-ce que la religion ? de Keiji Nishitani
Authors: Giraud Vincent
Published: October 2013

Nishitani Keiji (1900-1990) a mis en oeuvre une reprise féconde des questions propres à la tradition métaphysique occidentale en prenant appui sur la conception bouddhiste de la vacuité (japonais : kū ; sanscrit : śūnyatā) . Marchant sur les traces d’Augustin et de sa pensée de la conversion, il a lié aussi étroitement que possible pensée philosophique et quête religieuse. Le nouvel édifice conceptuel élaboré par Nishitani autour de la notion de śūnyatā ne prend en effet tout son sens que pour qui se rend capable d’une conversion au sens religieux du terme, décentrement radical de sa propre existence en direction de la vacuité, et permettant seul un accès véritable à l’être. La saisie par Nishitani de l’essence de la religion le conduit ainsi dans les parages de l’augustinisme, éclairant d’un jour nouveau le possible usage contemporain des catégories bouddhistes.
Cosmic ray solar modulation and Forbush decrease analyses based on atmospheric neutron spectrometry at mountain altitude and GEANT4 simulations of extensive air showers
Authors: Cheminet A. , Hubert G. , Lacoste V. , Maurin D. , Derome L.
Published: October 2013

A Bonner sphere spectrometer extended to high energies (HERMEIS) was set up at the summit of the Pic du Midi de Bigorre in the French Pyrenees (altitude: +2,885 m; geomagnetic cutoff: 5.6 GV) in May 2011. The spectral fluence rate distribution of the cosmic ray induced neutrons was continuously measured over a broad energy range from meV up to several GeV and with a 1 h time resolution. While the Sun's activity was increasing and reaching its 24th maximum in the 11 year solar cycle, some Forbush decreases were observed in the atmospheric secondary radiation at mountain altitude. We investigated the evolution of the cascade fluence rate (i.e., neutrons with energy greater than 20 MeV) during the March 2012 events with a series of strong coronal mass ejections hitting the Earth's magnetosphere. The amplitude of the greatest Forbush decrease peaked at 10%. Then, a simulation work based on the GEANT4 toolkit was carried out to quantify the solar modulation induced on the galactic cosmic ray transportation during these events. We performed calculations of extensive air showers generated by monoenergetic primaries (Hydrogen and Helium nuclei) for several zenith incidences. Hence, a complete database was built and validated. We derived an analytical model to estimate the atmospheric neutron spectrum at the Pic du Midi according to primary spectra which only depend on the solar modulation potential (force field approximation). We compared the solar modulation potentials obtained in March 2012 with the ones derived by the neutron monitor yield method. Finally, a satisfying agreement was found.
Testing the empirical shock arrival model using quadrature observations
Authors: Gopalswamy N. , Mäkelä P. , Xie H. , Yashiro S.
Published: October 2013

The empirical shock arrival (ESA) model was developed based on quadrature data from Helios (in situ) and P‐78 (remote sensing) to predict the Sun‐Earth travel time of coronal mass ejections (CMEs). The ESA model requires earthward CME speed as input, which is not directly measurable from coronagraphs along the Sun‐Earth line. The Solar Terrestrial Relations Observatory (STEREO) and the Solar and Heliospheric Observatory (SOHO) were in quadrature during 2010–2012, so the speeds of Earth‐directed CMEs were observed with minimal projection effects. We identified a set of 20 full halo CMEs in the field of view of SOHO that were also observed in quadrature by STEREO. We used the earthward speed from STEREO measurements as input to the ESA model and compared the resulting travel times with the observed ones from L1 monitors. We find that the model predicts the CME travel time within about 7.3 h, which is similar to the predictions by the ENLIL model. We also find that CME‐CME and CME‐coronal hole interaction can lead to large deviations from model predictions.
Dynamic, In Situ Generated Interfaces Between Carbon‐Bonded Alumina Filters and Steel During Spark Plasma Sintering/Field‐Assisted Sintering
Authors: Salomon Anton , Emmel Marcus , Dudczig Steffen , Rafaja David , Aneziris Christos G.
Published: October 2013

The aim of this study was to analyze possible reactions taking place during filtration of steel melts. The heterogeneous reactions and interface creation during short‐time contact of liquid steel and newly developed carbon bonded alumina ceramic filter (Al2O3‐C) were examined. The samples were produced using spark plasma sintering (SPS) to assure the absence of liquid convection. The production of the samples included very high heating rates of up to 1000 K min−1, short holding times just above liquidus temperature and a rapid cooling. The focus of the research was put on the inorganic inclusions (endogenous as well as exogenous), agglomerates, and phase formation. Exogenous inclusions (Al2O3) were added to the steel grade 42CrMo4 by a ball milling process. The results indicate the formation of MnS inclusions due to the high sulfur content in the used steel. The formation took place at the interfaces between steel and ceramic and at the grain boundaries within the steel. Penetration of the porous ceramic body by the steel was identified. Exogenous Al2O3 inclusions were found to agglomerate, adhere at the steel/Al2O3‐C interfaces and tended to float on top of the melt.
6Li Embedded Biaxially Stretched Scintillation Films for Thermal Neutron Detection and Neutron/Gamma Discrimination
Authors: Uppal Rohit , Sen Indraneel , Penumadu Dayakar , Young Stephen A. , Urffer Matthew J. , Miller Laurence F.
Published: October 2013

Biaxially stretched composite polyethylene naphthalate (PEN) films (BSCPF) embedded with submicron lithium fluoride (6LiF) particles and luminescent molecules were fabricated to make large area scintillation films (≈1 m × 1 m) for thermal neutron detection. BSCPF had 20.2% higher neutron light yield as compared to unstretched composite film (UCPF), and were 2.46 ± 1.47 times more efficient for detecting thermal neutrons than lithiated glass GS20 above lower level discriminator corresponding to an intrinsic efficiency for gamma <10−6. MCNPX simulations for a layered BSCPF detector resulted 6.1 cps for 1 ng 252Cf, thus meeting the Pacific Northwest National Laboratory criteria for absolute neutron detection efficiency and intrinsic gamma‐neutron discrimination. BSCPF have alpha to beta ratio of 0.25, which is higher than that for UCPF (0.11), and also for GS20 (0.22), which offers the possibility of excellent neutron/gamma discrimination.
Nucleoside Triphosphates as Promoters to Enhance Nanoceria Enzyme‐like Activity and for Single‐Nucleotide Polymorphism Typing
Authors: Xu Can , Liu Zhen , Wu Li , Ren Jinsong , Qu Xiaogang
Published: October 2013

Nucleoside triphosphates (NTPs) can improve the oxidase‐like activity of nanoceria and the enhancement is correlated with the type of NTP. This effect is demonstrated to be as a result of the coupling of the oxidative reaction with the NTP hydrolysis reactions, as the nanoceria has both oxidase‐like and phosphatase‐like activities. The differences reflect the different dephosphorylation catalytic activities of nanoceria to the NTP used. Furthermore, based on the NTP‐promoted oxidase‐like activity of nanoceria and the differences among the different types of NTPs, series effective and high‐throughput colorimetric assays for single‐nucleotide polymorphism (SNP) typing are developed.
Oxidative Alkene Cleavage by Chemical and Enzymatic Methods
Authors: Rajagopalan Aashrita , Lara Miguel , Kroutil Wolfgang
Published: October 2013

The cleavage of alkenes to the corresponding carbonyl products is a widely employed method in organic synthesis, especially to introduce oxygen functionalities into molecules, remove protecting groups and tailor large molecules. Chemical methods available for alkene cleavage include, for instance, ozonolysis, several metal‐based variants (KMnO4, OsO4, RuO4, etc.), electrochemical alternatives, singlet oxygen, hypervalent iodine and organic molecules in combination with oxygen. Furthermore, several enzymatic methods for alkene cleavage have been described to establish safe, mild and selective oxidation methods. Various heme and non‐heme iron‐dependent enzymes catalyse the alkene cleavage at ambient temperature and atmospheric pressure in an aqueous buffer, showing good chemo‐ and regioselectivities in selected cases. Quite recently some Cu‐, Mn‐ and Ni‐dependent enzymes have been identified for this reaction. This review gives an overview of the different chemical and enzymatic methods available for the cleavage of alkenes.

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Preparation of cellulose adsorbents with ionic liquid and pore expansion for chromatographic applications
Authors: Zhang Qi‐Lei , Shi Fei , Wang Peng , Lin Dong‐Qiang , Yao Shan‐Jing
Published: October 2013

Chromatography is a widely used technique in protein separation, and the adsorbents are essential to separate target proteins from raw mixtures. In this study, porous cellulose beads were prepared with a direct dissolution of microcrystalline cellulose (MCC) using an ionic liquid solvent 1‐butyl‐3‐methylimidazolium chloride. Pore expanding agents (cassava starch and cyclohexane) were added in MCC solutions to change the pore structure of the cellulose beads. The results showed that the mean pore size of cellulose beads increased after the application of pore expanding agents, whereas the wet density and the specific surface area were decreased. Residence time distribution studies indicated that the beads prepared with the addition of cyclohexane had the best performance for a series of molecules with different molecular weights. The cellulose beads were coupled with diethylaminoethyl and the adsorption properties with bovine serum albumin as a model protein showed that the beads prepared with cyclohexane had the best protein adsorption capability. The chromatographic results demonstrated that ionic liquids are effective solvents for cellulose dissolution and pore expanding agents can be used to enhance the pore structure of cellulose beads. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40060.
Synthesis and characterization of composite flocculant PAFS–CPAM for the treatment of textile dye wastewater
Authors: Sun Yongjun , Zheng Huaili , Tan Mingzhuo , Wang Yili , Tang Xiaomin , Feng Li , Xiang Xinyi
Published: October 2013

In this study, a new composite flocculant was prepared by premixing polymeric aluminum ferric sulfate (PAFS) with cationic polyacrylamide (CPAM) to treat textile dye wastewater. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were conducted to investigate the structure and morphology of the PAFS–CPAM. The effects of flocculant dosage, initial pH of textile dye wastewater, and settling time after flocculation on the removal of turbidity and chemical oxygen demand (COD) were examined. The flocculation efficiency of PAFS–CPAM for dye treatment was compared with PAFS, CPAM, PAFS/CPAM (PAFS followed by CPAM), and CPAM/PAFS (CPAM followed by PAFS). The synergy of PAFS and CPAM increased the (Fe–Al)b species of PAFS–CPAM. Treatment with PAFS–CPAM was more effective in removing turbidity and COD than PAFS, CPAM, PAFS/CPAM, and CPAM/PAFS. The turbidity and COD removal rates of textile wastewater were higher than 80 and 90% in the pH range of 5.5 to 8.5, respectively. Furthermore, PAFS–CPAM demonstrated excellent performance in reducing sludge volume after flocculation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40062.
Study on ester–amide exchange reactions between Nylon 1010 and Ethylene‐vinyl acetate rubber
Authors: Lu Xianbo , Zhang Hongmei , Zhang Yong
Published: October 2013

Reactive processing is a useful method to improve the compatibility of immiscible polymer blends. Nylon 1010/Ethylene‐vinyl acetate rubber (EVM) blends were prepared via melt blending at 240°C and tetrabutyl titanate (Ti(OBu)4) was used as a catalyst. Ester–amide exchange reactions were proven to take place between Nylon and EVM during the shear processing. Melt flow index, Fourier transform infrared spectroscopy, and proton nuclear magnetic resonance spectra were used to study the reactions. It was demonstrated that tuning the shear rate could control the properties and reaction extent of Nylon 1010/EVM/Ti(OBu)4 blends. The results revealed that the reactions were promoted by high shear rate. Tensile strength of the blends increased from 4.5 to 11.4 MPa when the shear rate increased from 20 to 80 rpm. Meanwhile, scanning electron microscopy was adopted to study the morphology of the reactive blends. It was found that the morphology of the blends was changed from sea‐island structures to co‐continuous structures while increasing the shear rate from 20 to 100 rpm. Dynamic mechanical analysis confirmed that high‐shear processing was found to promote the compatibility of the blends. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40064.
The p38‐Mediated Rapid Down‐Regulation of Cell Surface gp130 Expression Impairs Interleukin‐6 Signaling in the Synovial Fluid of Juvenile Idiopathic Arthritis Patients
Authors: Honke Nora , Ohl Kim , Wiener Anastasia , Bierwagen Jeff , Peitz Joachim , Di Fiore Stefano , Fischer Rainer , Wagner Norbert , Wüller Stefan , Tenbrock Klaus
Published: October 2013

Objective

Interleukin‐6 (IL‐6) signaling plays an important proinflammatory role, but this role is restricted by regulatory mechanisms that, for example, reduce the cell surface availability of the signal‐transducing chain of the IL‐6 receptor, gp130. The aim of this study was to determine whether the inflammatory environment in arthritic joints has an impact on monocytic gp130 surface expression and the extent to which regulatory processes in the synovial fluid (SF) can be reproduced in an in vitro model.

Methods

Flow cytometry and live cell imaging were used to measure the cell surface expression and internalization of gp130. STAT‐3 phosphorylation was monitored by flow cytometry and Western blotting.

Results

In patients with juvenile idiopathic arthritis (JIA), levels of cell surface gp130 expression in SF monocytes were reduced compared to those in peripheral blood (PB) monocytes. These reduced levels were reproduced when PB monocytes from healthy donors were stimulated with SF, and this reduction was dependent on p38 MAPK. The induction of p38 by IL‐1β in PB monocytes interfered with IL‐6 signaling due to the reduced cell surface expression of gp130.

Conclusion

These results suggest that p38‐mediated proinflammatory stimuli induce the down‐regulation of gp130 on monocytes and thus restrict gp130‐mediated signal transduction. This regulatory mechanism could be of relevance to processes in the inflamed joints of patients with JIA.
Interleukin‐6 Receptor Blockade Enhances CD39+ Regulatory T Cell Development in Rheumatoid Arthritis and in Experimental Arthritis
Authors: Thiolat A. , Semerano L. , Pers Y. M. , Biton J. , Lemeiter D. , Portales P. , Quentin J. , Jorgensen C. , Decker P. , Boissier M.‐C. , Louis‐Plence P. , Bessis N.
Published: October 2013

Objective

The rationale for blocking interleukin‐6 (IL‐6) in rheumatoid arthritis (RA) lies chiefly in the proinflammatory effect of this cytokine. Few studies have evaluated the consequences of anti–IL‐6 receptor (IL‐6R) antibody treatment on Treg cells. This study was undertaken to elucidate the mechanism of action of anti–IL‐6R antibody treatment by studying the effects on Treg cells in an experimental arthritis model and in patients with RA.

Methods

Mice with collagen‐induced arthritis (CIA) were treated with a mouse anti–IL‐6R antibody (MR16‐1), and changes in Treg, Th1, and Th17 cells were assessed at key time points during the course of the disease. Peripheral blood from 15 RA patients was collected on day 0 and after 3 months of tocilizumab treatment for flow cytometry analysis of Th17 and Treg cells.

Results

In MR16‐1–treated mice, Th17 cell frequencies were unchanged, whereas Treg cell frequencies were increased. The Treg cell phenotype showed marked changes, with an increase in the frequency of CD39+ Treg cells in the lymph nodes and spleen. Interestingly, similar CD39+ Treg cell expansion was observed in RA patients who were tocilizumab responders at 3 months, with no change in Th17 cell frequency. Moreover, fluorescence‐activated cell–sorted CD39+ Treg cells from responder RA patients were functionally able to suppress the proliferation of conventional T cells.

Conclusion

In both CIA and RA, the frequency of functionally suppressive CD39+ Treg cells is increased as a result of anti–IL‐6R treatment, whereas Th17 cells are unaffected. The modification of Treg cell frequency and phenotype may be one of the mechanisms involved in the therapeutic effect of IL‐6 blockade in RA.
Pathogenic Mechanisms in Lupus Nephritis: Nucleosomes Bind Aberrant Laminin β1 With High Affinity and Colocalize in the Electron‐Dense Deposits
Authors: Olin Anders I. , Mörgelin Matthias , Truedsson Lennart , Sturfelt Gunnar , Bengtsson Anders A.
Published: October 2013

Objective

Apoptotic nucleosomes are structurally and immunologically involved in lupus nephritis. The purpose of this study was to examine the expression and function of laminins and their interactions with nucleosomes in the kidneys of patients with lupus nephritis, using surface plasmon resonance (SPR) analysis.

Methods

SPR interaction analysis was used to quantify the strength of laminin–nucleosome interactions. Electron microscopy techniques were used to determine in vivo colocalization of IgG, chromatin, and laminin β1, as well as to characterize nucleosome–laminin interactions in vitro.

Results

Nucleosomes were found to possess high affinity for laminin β1–containing laminins and to have the potential to form stable molecular complexes with these structures. In vivo, laminin β1 was aberrantly expressed in the glomerular basement membrane (GMB) of lupus nephritis patients, and in situ, it acted as a nucleosome ligand, selectively colocalizing with nucleosomes within electron‐dense deposits (EDDs). Normal adult laminin 11, which contains laminin β2, did not bind nucleosomes, and it did not colocalize in vivo with the nucleosomes in the nephritic GBM. In addition, TGFβ1 was expressed by the glomerular mesangium, glomerular endothelial cells, and by podocytes in patients with lupus nephritis. It was trapped in situ within EDDs by an as‐yet‐unknown ligand. As was recently described in a transgenic mouse model, paracrine kidney glomerular TGFβ1 may thereby contribute to the development of glomerulopathy via the induction of laminin β1 incorporation in the GBM, whereas systemic blood vessel–derived TGFβ1 could be trapped during filtration.

Conclusion

Our findings of the specific high‐affinity binding of nucleosomes to aberrantly expressed laminin β1 in the GBM and their colocalization in the GBM may explain important features of the initial steps in the pathogenesis of lupus nephritis, the planted antigen hypothesis.