bluuebunny/crossref_metadata_2025 huggingface dataset:
Dominant climatic factor driving annual runoff change at catchments scale over China
Authors: Huang Z. , Yang H.
Published: December 2015

Abstract. With global climate changes intensifying, the hydrological response to climate changes has attracted more attentions. It is beneficial not only for hydrology and ecology but also for water resources planning and management to reveal the impacts of climate change on runoff. It is of great significance of climate elasticity of runoff to estimate the impacts of climatic factors on runoff. In addition, there are large spatial variations in climate type and geography characteristics over China. To get a better understanding the spatial variation of runoff response to climate variables change and detect the dominant climatic factor driving annual runoff change, we chose the climate elasticity method proposed by Yang and Yang (2011), where the impact of the catchment characteristics on runoff was represented by a parameter n. The results show that the dominant climatic factor driving annual runoff is precipitation in the most part of China, net radiation in the lower reach of Yangtze River Basin, the Pearl River Basin, the Huai River Basin and the southeast area, and wind speed in part of the northeast China.
Effects of record length and resolution on the derived distribution of annual precipitation
Authors: Meier C. I. , Moraga J. S. , Pranzini G. , Molnar P.
Published: December 2015

Abstract. Traditional frequency analysis of annual precipitation requires the fitting of a probability model to yearly precipitation totals. There are three potential problems with this approach: a long record (at least 25 ~ 30 years) is required in order to fit the model, years with missing data cannot be used, and the data need to be homogeneous. To overcome these limitations, we test an alternative methodology proposed by Eagleson (1978), based on the derived distribution approach (DDA). This allows for better estimation of the probability density function (pdf) of annual rainfall without requiring long records, provided that high-resolution precipitation data are available to derive external storm properties. The DDA combines marginal pdfs for storm depth and inter-arrival time to arrive at an analytical formulation of the distribution of annual precipitation under the assumption of independence between events. We tested the DDA at two temperate locations in different climates (Concepción, Chile, and Lugano, Switzerland), quantifying the effects of record length. Our results show that, as compared to the fitting of a normal or log-normal distribution, the DDA significantly reduces the uncertainty in annual precipitation estimates (especially interannual variability) when only short records are available. The DDA also reduces the bias in annual precipitation quantiles with high return periods. We also show that using precipitation data aggregated every 24 h, as commonly available at most weather stations, introduces a noticeable bias in the DDA. Our results point to the tangible benefits of installing high-resolution (hourly or less) precipitation gauges at previously ungauged locations. We show that the DDA, in combination with high resolution gauging, provides more accurate and less uncertain estimates of long-term precipitation statistics such as interannual variability and quantiles of annual precipitation with high return periods even for records as short as 5 years.
Comparison of measured brightness temperatures from SMOS with modelled ones from ORCHIDEE and H-TESSEL over the Iberian Peninsula
Authors: Barella-Ortiz A. , Polcher J. , de Rosnay P. , Piles M. , Gelati E.
Published: December 2015

Abstract. L-Band radiometry is considered to be one of the most suitable techniques to estimate surface soil moisture by means of remote sensing. Brightness temperatures are key in this process, as they are the main input in the retrieval algorithm. The work exposed compares brightness temperatures measured by the Soil Moisture and Ocean Salinity (SMOS) mission to two different sets of modelled ones, over the Iberian Peninsula from 2010 to 2012. The latter were estimated using a radiative transfer model and state variables from two land surface models: (i) ORganising Carbon and Hydrology In Dynamic EcosystEms (ORCHIDEE) and (ii) Hydrology – Tiled ECMWF Scheme for Surface Exchanges over Land (H-TESSEL). The radiative transfer model used is the Community Microwave Emission Model (CMEM). A good agreement in the temporal evolution of measured and modelled brightness temperatures is observed. However, their spatial structures are not consistent between them. An Empirical Orthogonal Function analysis of the brightness temperature's error identifies a dominant structure over the South-West of the Iberian Peninsula which evolves during the year and is maximum in Fall and Winter. Hypotheses concerning forcing induced biases and assumptions made in the radiative transfer model are analysed to explain this inconsistency, but no candidate is found to be responsible for it at the moment. Further hypotheses are proposed at the end of the paper.
Surface speed and frontal ablation of Kronebreen and Kongsbreen, NW Svalbard, from SAR offset tracking
Authors: Schellenberger T. , Dunse T. , Kääb A. , Kohler J. , Reijmer C. H.
Published: December 2015

Abstract. Kronebreen and Kongsbreen are among the fastest-flowing glaciers on Svalbard and, therefore, important contributors to the total dynamic mass loss from the archipelago. Here, we present a time series of area-wide surface velocity fields from April 2012 to December 2013 based on offset tracking on repeat high-resolution Radarsat-2 Ultrafine data. Surface speeds reached up to 3.2 m d−1 near the calving front of Kronebreen in summer 2013 and 2.7 m d−1 at Kongsbreen in late autumn 2012. Additional velocity fields from Radarsat-1, Radarsat-2 and TerraSAR-X data since December 2007 together with continuous GPS measurements on Kronebreen since September 2008 revealed complex patterns in seasonal and interannual speed evolution. Part of the ice-flow variations seem closely linked to the amount and timing of surface meltwater production and rainfall, both of which are known to have a strong influence on the basal water pressure and hence basal lubrication. In addition, terminus retreat and the associated reduction in back stress appear to have influenced the speed close to the calving front, especially at Kongsbreen in 2012 and 2013. Since 2007, Kongsbreen retreated up to 1800 m, corresponding to a total area loss of 2.5 km2. In 2011 the retreat of Kronebreen of up to 850 m, responsible for a total area loss of 2.8 km2, was triggered after a phase of stable terminus position since ~ 1990. Retreat is an important component of the mass balance of both glaciers, in which frontal ablation is the largest component. Total frontal ablation between April 2012 and December 2013 was estimated to 0.21–0.25 Gt a−1 for Kronebreen and 0.14–0.16 Gt a−1 for Kongsbreen.
Crisis del petróleo, transición a la democracia y frenazo de la expansión turística en España, 1973-1985
Authors: Luque Aranda Marta , Pellejero Martínez Carmelo
Published: December 2015

El objetivo del presente trabajo es analizar los notables efectos que la crisis del petróleo de los años setenta y el final del crecimiento dorado de las economías occidentales, una coyuntura que en España tuvo el añadido de la transición política a la democracia, provocaron sobre las demandas turísticas nacional e internacional, por vez primera desde 1946 con tasas anuales de variación negativas; sobre el sector hotelero, seriamente afectado por problemas de capitalización; y sobre la política turística aplicada por los poderes públicos, bastante continuista y muy condicionada por los cambios institucionales impuestos por la Constitución aprobada en 1978.
El primer tropiezo histórico de Bonaparte: la reconquista de Santo Domingo
Authors: Pinto Antonio J.
Published: December 2015

El objetivo de este trabajo es estudiar el primer tropiezo histórico de las tropas de Napoleón Bonaparte, en Santo Domingo, y los paralelismos entre la Guerra de Independencia española y la Reconquista dominicana. Para ello se han analizado los testimonios de los personajes implicados, con el fin de indagar el ideario que inspiró su acción militar. Además probaremos que, contra las ideas defendidas por algunos historiadores, tras la paz de Basilea los dominicanos siguieron sintiéndose ligados a España, como demostraron en la Guerra de Reconquista contra el gobierno francés. Sólo Cuba, Puerto Rico y Santo Domingo participaron de este sentimiento, mientras el resto de Hispanoamérica comenzaba a clamar por la independencia.
"A noite branca", entre o documental e o ficcional: a memoria silenciada da División Azul
Authors: Vilavedra Dolores
Published: December 2015

El artículo indaga en la ambigua condición fenomenológica de la novela A noite branca (La noche blanca) de Francisco Fernández Naval, publicada en gallego en 2012, ambigüedad producida tanto por su hibridez discursiva como por el difuso estatuto ontológico de los hechos narrados y de varios personajes. El esclarecimiento de las estrategias con las que se construye dicha ambigüedad, junto a la originalidad del tema, en el conjunto de textos narrativos gallegos que abordan la memoria de la Guerra Civil y la Posguerra, permite valorar ajustadamente los méritos literarios de la novela.
Automatic System for Producing and Distributing Lecture Recordings and Livestreams Using Opencast Matterhorn
Authors: Jonach Rafeal , Ebner Martin , Grigoriadis Ypatios
Published: December 2015

Lectures of courses at universities are increasingly being recorded and offered through various distribution channels to support students’ learning activities. This research work aims to create an automatic system for producing and distributing high quality lecture recordings. Opencast Matterhorn is an open source platform for automated video capturing and distribution and will be integrated fully in the introduced system. Beside lecture recordings livestreams of events in lecture halls are also being distributed, so that students have access to lecture content anywhere. In this publication we describe the technical implementation as well as discuss the strength and the weakness of such solution.
A Framework for Conducting Critical Dialectical Pluralist Focus Group Discussions Using Mixed Research Techniques
Authors: Onwuegbuzie Anthony J. , Frels Rebecca K.
Published: December 2015

Although focus group discussions (FGDs) represent a popular data collection tool for researchers, they contain an extremely serious flaw: FGD researchers have ultimate power over all decisions made at every stage of the research process—from the conceptualization of the research, to the planning of the research study, to the implementation of the research study, to the dissemination of FGD findings. Yet, exercising 100% control over all decisions in FGD research can be detrimental for some participants, especially for under-represented, underserved, and marginalized populations. Thus, in this article, we introduce a new type of participant-directed FGD, which we call a critical dialectical pluralist FGD, wherein participants are maximally empowered to make decisions at every stage of the mixed research process. We outline the stages of critical dialectical pluralist FGDs and provide a real-life example of this approach.
Valuation of Quanto Floating Range Notes under the Cross-Currency LIBOR Market Model
Authors: Chou Chi-Hsun , Hsieh Tsung-Yu , Chen Son-Nan
Published: December 2015

In this paper, we propose analytical valuation formulae for three types of quanto ﬂoating range notes based on the cross-currency LIBOR market model. The dynamics of forward LIBOR rates is a multifactor model that incorporates both the domestic and foreign interest rate process and the exchange rate process in a cross-currency environment. The derived formulae are analytically tractable and easy to implement in practice. The model parameters can be extracted directly from market quantities. We show that the empirical results are more accurate and robust than the results ofMonte Carlosimulation.
Forms of Violence in the Affective-Sexual Relationships of Adolescents
Authors: Marasca Aline Riboli , Falcke Denise
Published: December 2015

Violence in the affective-sexual relationships of adolescents is a theme that has been highlighted by the literature as a result of its high rates of prevalence. It has different characteristics, while many factors are shown to be associated with its occurrence. The present study investigated the affective-sexual relationships of adolescents, focusing on the experiences as perpetrators and victims of different types of violence between partners. We conducted a quantitative study with a descriptive, comparative and correlational design, with 124 heterosexual adolescents, aged 15 to 18 years (M = 15.94, SD = 0.65). As measurement instruments we used a sociodemographic questionnaire, the Family Background Questionnaire (FBQ), and the Conflict in Adolescent Dating Relationships Inventory (CADRI). The results showed percentages of violence that ranged from 14.7% for relational abuse committed to 97% for verbal/emotional violence suffered. We identified significant gender differences in the dimensions of threatening behavior (t = -3.172, p = 0.002) and physical violence (t = -3.037, p = 0.003) perpetrated by the participant, indicating that it is the girls who report that they practice this type of violence more often. No significant correlation was observed between experiences of violence in the family of origin and in the relationship with the partner (p > 0.05). However, there was an association between the occurrence of violence in the relationships of the adolescents and the presence of violence in the affective-sexual relationships of friends (p < 0.05). We highlight the importance of expanding the field of theory regarding this phenomenon, in order to assist with future interventions.
Hippocampal ensemble dynamics timestamp events in long-term memory
Authors: Rubin Alon , Geva Nitzan , Sheintuch Liron , Ziv Yaniv
Published: December 2015

The capacity to remember temporal relationships between different events is essential to episodic memory, but little is currently known about its underlying mechanisms. We performed time-lapse imaging of thousands of neurons over weeks in the hippocampal CA1 of mice as they repeatedly visited two distinct environments. Longitudinal analysis exposed ongoing environment-independent evolution of episodic representations, despite stable place field locations and constant remapping between the two environments. These dynamics time-stamped experienced events via neuronal ensembles that had cellular composition and activity patterns unique to specific points in time. Temporally close episodes shared a common timestamp regardless of the spatial context in which they occurred. Temporally remote episodes had distinct timestamps, even if they occurred within the same spatial context. Our results suggest that days-scale hippocampal ensemble dynamics could support the formation of a mental timeline in which experienced events could be mnemonically associated or dissociated based on their temporal distance.
Structural basis for activation, assembly and membrane binding of ESCRT-III Snf7 filaments
Authors: Tang Shaogeng , Henne W Mike , Borbat Peter P , Buchkovich Nicholas J , Freed Jack H , Mao Yuxin , Fromme J Christopher , Emr Scott D
Published: December 2015

The endosomal sorting complexes required for transport (ESCRTs) constitute hetero-oligomeric machines that catalyze multiple topologically similar membrane-remodeling processes. Although ESCRT-III subunits polymerize into spirals, how individual ESCRT-III subunits are activated and assembled together into a membrane-deforming filament remains unknown. Here, we determine X-ray crystal structures of the most abundant ESCRT-III subunit Snf7 in its active conformation. Using pulsed dipolar electron spin resonance spectroscopy (PDS), we show that Snf7 activation requires a prominent conformational rearrangement to expose protein-membrane and protein-protein interfaces. This promotes the assembly of Snf7 arrays with ~30 Å periodicity into a membrane-sculpting filament. Using a combination of biochemical and genetic approaches, both in vitro and in vivo, we demonstrate that mutations on these protein interfaces halt Snf7 assembly and block ESCRT function. The architecture of the activated and membrane-bound Snf7 polymer provides crucial insights into the spatially unique ESCRT-III-mediated membrane remodeling.
Some like it hot, but not too hot
Authors: Greppi Chloe , Budelli Gonzalo , Garrity Paul A
Published: December 2015

A temperature-sensitive receptor prevents mosquitoes from being attracted to targets that are hotter than a potential host.
Synthesis of nitrogen-containing carbon by solution plasma in aniline with high-repetition frequency discharges
Authors: Hyun Koangyong , Ueno Tomonaga , Saito Nagahiro
Published: December 2015

Nitrogen-containing carbon nanoparticles were synthesized in aniline by solution plasma with high-repetition frequency discharges. We developed a bipolar pulsed power supply that can apply high-repetition frequencies ranging from 25 to 200 kHz. By utilizing high-repetition frequencies, conductive carbons were directly synthesized. The crystallinity was increased and H/C ratio of carbon was decreased. Furthermore, nitrogen atoms were simultaneously embedded in the carbon matrix. Due to the presence of nitrogen atoms, the conductivity and electrocatalytic activity of the samples were remarkably improved compared to that of a pure carbon matrix synthesized from a benzene precursor.
Aeration in Biotechnology
Authors: Nienow Alvin W.
Published: December 2015

The supply of oxygen to a growing organism, aeration, in bioreactors is a critical requirement in biotechnology because of the limited solubility of oxygen in water. Aeration involves transfer of oxygen from the air into the fluid surrounding the organism, from where it is transferred to the organism itself. During the course of a batch bioreaction, oxygen demand often passes through a marked maximum when the species is most biologically active. The basic principles that underlie aeration are exactly the same as those that determine the rate of transfer of any sparingly soluble gas (oxygen) from the gas stream (air) to the unsaturated liquid (broth). In each case, energy is dissipated to increase the rate of transfer beyond simple diffusion, and the mode of energy input defines the two‐phase fluid dynamics. Though there are many different types of bioreactor, there are basically four ways of imparting the energy required: rotating agitators (stirred tanks), gas compression (bubble columns/loop fermenters), liquid circulating (jet loop reactors), and shaking (shake flasks, microtiter plates), the last one being common at the screening stage of process development and in clone selection. In addition, the transfer rate depends on the area of contact between the phases, the driving force available (ie, the difference in concentration of oxygen in the two phases), the chemical composition of the liquid, and its temperature. Aeration is used in bacterial, aerobic yeast, polysaccharide, and mycelial fermentations, animal, stem, and plant cell culture, single‐cell protein production, and biological aerobic wastewater treatment.
Bulk Solids Handling
Authors: Marinelli Joseph , Carson John W. , McGlinchey Don , Cowell Andrew
Published: December 2015

The field of bulk solids flow has been developed considerably since the development of the theory of bulk solids flow began in early 1950s, which allowed the design of equipment and testing methods. More recent advances in numerical modeling have had a significant impact on the design methodology of bulk solids handling equipment.

In this article, bulk flow patterns, measurement, and their simulation, as well as equipment design and maintenance are described. Special considerations including sifting, and mixing and blending, are also discussed.
Polymer Fracture
Authors: Kausch‐Blecken von Schmeling H. H. , Williams J. G.
Published: December 2015

Fracture of polymers is defined as the stress‐biased material disintegration through the formation of new surface within a body. The essential molecular damage mechanisms leading to crack initiation followed by stable and/or unstable crack propagation are described; fracture phenomena are identified and quantified using different concepts of fracture mechanics (linear elastic, confined plasticity, essential work of fracture). Particular attention has been given to a discussion of toughness and time‐dependent strength in terms of molecular and material parameters (eg, composition, chain architecture, degree of entanglement, and molecular mobility) and of extrinsic variables (state of stress, rate of loading, environment). However, the important aspect offatigue behavioris treated in an independent part in this Encyclopedia.
Neutron Scattering of Soft Materials
Authors: Dadmun Mark
Published: December 2015

Analysis of the scattering patterns from soft materials is a powerful technique that provides information on the structure and dynamics of large‐scale structures such as polymers, proteins, colloids, and biological complexes. Moreover, the ability to selectively highlight a macromolecule by targeted deuteration provides neutrons the unique ability to examine macromolecules in dilute and concentrated solutions, as well as in the melt. In this article, the methods of correlating the structure of a scattering sample to the measured neutron‐scattering pattern is overviewed to provide a fundamental understanding of the use of neutron scattering to examine soft materials, while advantages and limitations of the technique are also raised. Finally, a series of examples where scientists have utilized neutron scattering to examine the structure and thermodynamics of polymeric and biological molecules are presented, with the hope that this introduction will provide the reader with the information needed to examine the use of neutron scattering in their own research.
Reversible Deactivation Radical Polymerization
Authors: Klumperman Bert
Published: December 2015

Reversible deactivation radical polymerization (RDRP), formerly known as living radical polymerization (LRP), is the general name for a family of polymerization techniques. The techniques have in common that the propagating species is a free radical and that an equilibrium exists between active (free radical) species and dormant species. Because of this equilibrium (nearly), all chains grow throughout the polymerization reaction. This leads to polymers with predetermined degree of polymerization and (usually) narrow molar mass distribution. A historical overview of the development of RDRP is provided, and the three most important techniques are discussed in more detail. These three techniques are (1) nitroxide‐mediated polymerization, (2) transition metal‐mediated radical polymerization techniques, such as atom transfer radical polymerization, (3) reversible addition–fragmentation chain‐transfer–mediated polymerization, with most emphasis on the latter two. The general kinetics and some boundary conditions for obtaining low molar mass dispersities (
Đ
) polymers are discussed. Furthermore, the scope and limitations of the three major polymerization techniques are outlined.

Apart from the predetermined molar mass and the
Đ
, RDRP is of particular interest in the synthesis of advanced architectures. These architectures include block copolymers, star‐branched polymers, telechelic polymers, gradient or tapered copolymers, etc. Among the major advantages of RDRP is the fact that most of the benefits of free‐radical polymerization (FRP) are retained. Thus, the possibility to (co)polymerize functional monomers (hydroxyl, epoxy, amide, anhydride, etc) and the possibility to polymerize under nondemanding conditions are typical for FRP as well as for RDRP.
Flame Retardants
Authors: Weil Edward D.
Published: December 2015

Flame retardants believed to be in actual use, recently discontinued, or believed to be under commercial development, are surveyed and classified by main chemical types: inorganic, halogenated (organic), phosphorus‐based, sulfur‐based, and nitrogen‐based. Both additive and reactive types are discussed. Mode of action and environmental factors are briefly discussed. Evidence for the value of flame retardants for life safety is presented. The use of high molecular weight additives, reactives, or inorganic additives is shown as a current strategy for avoiding environmental concerns.
Polymerization in Ionic Liquids
Authors: Zhang Hongwei , Behera Prasanta Kumar , Singha Nikhil K. , Hong Kunlun , Mays Jimmy W.
Published: December 2015

Room temperature ionic liquids (RTILs) have proved over recent years to be useful and unique reaction media for a variety of chemical reactions. Faster reaction rates and better selectivities are often observed in RTILs as compared to those in common organic solvents. In addition to these advantages, the low volatility, nonflammability, and recycling potential also help RTILs become a preferred alternative reaction medium to meet environmental and other requirements. This is evidenced by the ever increasing number of papers published in this area every year and interesting and important discoveries. When conventional free radical polymerizations are carried out in RTILs, there is an increase in the propagation rate due to the high polarity of the RTIL and a decrease in the termination rate because of the high viscosity of the RTILs, and thus the overall reaction rate is greatly increased along with an increase in molecular weight. For living/controlled polymerization such as atom transfer radical polymerization and radical addition‐fragmentation and transfer, the reactions in RTILs are still controllable with faster reaction rates and easy separation of catalysts and/or ligands from the resulting polymers. Nearly all types of polymerization processes have now been successfully conducted in RTILs, often with advantageous effects.
Structure and Property Diversity of Chiral Helicene Oligomers
Authors: Saito Nozomi , Shigeno Masanori , Yamaguchi Masahiko
Published: December 2015

Helicenes are nonplanar polycyclic aromatic compounds formed by ortho‐fused aromatic rings, which have helical chirality. Incorporating helicenes into oligomers and polymers can provide a huge diversity of structure and property. 1,12‐Dimethylbenzo[c]phenanthrenes were employed in this study for such an approach. Various helicene oligomers have been synthesized, which differ in the helicene structure, chirality, spacer structure, side chain structure, oligomer length, linker structure, cyclic/acyclic mode, and homo‐/hetero‐multidomain mode. The oligomers exhibited various reversible aggregation/disaggregation properties and formed bimolecular, trimolecular, polymolecular, inter/intramolecular, and tetramolecular ααββ aggregates. Reversible self‐assembly of the aggregates can occur, providing gels, vesicles, liquid crystals, and self‐assembled monolayers (SAM). Dynamic properties are also a notable feature of the helicene oligomers, which include sharp thermal responses, thermal hysteresis, memory effect, self‐catalysis, the capability to count the numbers 1 and 2, and concentration amplification. The properties range from the molecular level to the molecular aggregate, self‐assembly, and bulk levels, which can be tuned by structural modifications of helicene oligomers.
Analytic radiative‐advective equilibrium as a model for high‐latitude climate
Authors: Cronin Timothy W. , Jansen Malte F.
Published: December 2015

We propose radiative‐advective equilibrium as a basic‐state model for the high‐latitude atmosphere. Temperature profiles are determined by a competition between stabilization by atmospheric shortwave absorption and advective heat flux convergence, and destabilization by surface shortwave absorption. We derive analytic expressions for temperature profiles, assuming power law atmospheric heating profiles as a function of pressure and two‐stream windowed‐gray longwave radiative transfer. We discuss example profiles with and without an atmospheric window and show that the sensitivity of surface temperature to forcing depends on the nature of the forcing, with greatest sensitivity to radiative forcing by increased optical thickness and least sensitivity to increased atmospheric heat transport. These differences in sensitivity of surface temperature to forcing can be explained in terms of a forcing‐dependent lapse‐rate feedback.
Ion‐driven instabilities in the solar wind: Wind observations of 19 March 2005
Authors: Gary S. Peter , Jian Lan K. , Broiles Thomas W. , Stevens Michael L. , Podesta John J. , Kasper Justin C.
Published: December 2015

Intervals of enhanced magnetic fluctuations have been frequently observed in the solar wind. But it remains an open question as to whether these waves are generated at the Sun and then transported outward by the solar wind or generated locally in the interplanetary medium. Magnetic field and plasma measurements from the Wind spacecraft under slow solar wind conditions on 19 March 2005 demonstrate seven events of enhanced magnetic fluctuations at spacecraft‐frame frequencies somewhat above the proton cyclotron frequency and propagation approximately parallel or antiparallel to the background magnetic field Bo. The proton velocity distributions during these events are characterized by two components: a more dense, slower core and a less dense, faster beam. Observed plasma parameters are used in a kinetic linear dispersion equation analysis for electromagnetic fluctuations at k x Bo = 0; for two events the most unstable mode is the Alfvén‐cyclotron instability driven by a proton component temperature anisotropy T⊥/T|| > 1 (where the subscripts denote directions relative to Bo), and for three events the most unstable mode is the right‐hand polarized magnetosonic instability driven primarily by ion component relative flows. Thus, both types of ion anisotropies and both types of instabilities are likely to be local sources of these enhanced fluctuation events in the solar wind.
Zonal currents in the F region deduced from Swarm constellation measurements
Authors: Lühr Hermann , Kervalishvili Guram , Rauberg Jan , Stolle Claudia
Published: December 2015

The Swarm constellation has been used to estimate zonal currents in the topside F region ionosphere at about 500 km. Near‐simultaneous magnetic field measurements from two altitudes but the same meridian are used for the current density calculations. We consider the period 15 February to 23 June 2014 for deriving a full 24 h local time coverage of the latitudinal distribution over ±50° in magnetic latitude. Intervals with close orbital phasing at the two heights are considered, which repeat every 6 days. From such days seven successive orbits are used where the epochs of equator crossings differ by less than 2 min. Deduced current densities are predominantly eastward (about 20 nA/m2) on the dayside and westward (about 10 nA/m2) on the nightside. A number of different drivers contribute to the observed total current. We identified the gravity‐driven eastward current as the most prominent at low latitudes. Eastward currents in the Northern Hemisphere are clearly stronger than in the south. This is attributed to the proximity of our study period to June solstice, when the solar radiation is stronger in the north. In addition, interhemispheric winds from the Northern (summer) to the Southern (winter) Hemisphere contribute. They cause eastward currents in the north and westward in the south. We find a relatively large variability of the zonal currents both in space and time. The standard deviation is at least twice as large as the mean value of current density. This large variability is suggested to be related to gravity wave forcing from below.
Does size matter? Statistical limits of paleomagnetic field reconstruction from small rock specimens
Authors: Berndt Thomas , Muxworthy Adrian R. , Fabian Karl
Published: December 2015

As samples of ever decreasing sizes are being studied paleomagnetically, care has to be taken that the underlying assumptions of statistical thermodynamics (Maxwell‐Boltzmann statistics) are being met. Here we determine how many grains and how large a magnetic moment a sample needs to have to be able to accurately record an ambient field. It is found that for samples with a thermoremanent magnetic moment larger than 10−11Am2 the assumption of a sufficiently large number of grains is usually given. Standard 25 mm diameter paleomagnetic samples usually contain enough magnetic grains such that statistical errors are negligible, but “single silicate crystal” works on, for example, zircon, plagioclase, and olivine crystals are approaching the limits of what is physically possible, leading to statistic errors in both the angular deviation and paleointensity that are comparable to other sources of error. The reliability of nanopaleomagnetic imaging techniques capable of resolving individual grains (used, for example, to study the cloudy zone in meteorites), however, is questionable due to the limited area of the material covered.
An examination of double‐diffusive processes in a mesoscale eddy in the Arctic Ocean
Authors: Bebieva Yana , Timmermans Mary‐Louise
Published: December 2015

Temperature and salinity measurements of an Atlantic Water mesoscale eddy in the Arctic Ocean's Canada Basin are analyzed to understand the effects of velocity shear on a range of double‐diffusive processes. Double‐diffusive structures in and around the eddy are examined through the transition from low shear (outside the eddy and within its solid body core) to high geostrophic shear zones at the eddy flanks. The geostrophic Richardson number takes large values where a double‐diffusive staircase is observed and lowest values at the eddy flanks where geostrophic velocity is largest and a well‐formed staircase is not present. A Thorpe scale analysis is used to estimate turbulent diffusivities in the flank regions. Double‐diffusive and turbulent heat, salt, and buoyancy fluxes from the eddy are computed, and used to infer that the eddy decays on time scales of around 4–9 years. Fluxes highlight that Atlantic Water heat within the eddy can be fluxed downward into deeper water layers by means of both double‐diffusive and turbulent mixing. Estimated lateral variations in vertical fluxes across the eddy allow for speculation that double diffusion speeds up the eddy decay, having important implications for the transfer of Atlantic Water heat in the Arctic Ocean.
A new framework for comprehensive, robust, and efficient global sensitivity analysis: 1. Theory
Authors: Razavi Saman , Gupta Hoshin V.
Published: December 2015

Computer simulation models are continually growing in complexity with increasingly more factors to be identified. Sensitivity Analysis (SA) provides an essential means for understanding the role and importance of these factors in producing model responses. However, conventional approaches to SA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we present a new and general sensitivity analysis framework (called VARS), based on an analogy to “variogram analysis,” that provides an intuitive and comprehensive characterization of sensitivity across the full spectrum of scales in the factor space. We prove, theoretically, that Morris (derivative‐based) and Sobol (variance‐based) methods and their extensions are special cases of VARS, and that their SA indices can be computed as by‐products of the VARS framework. Synthetic functions that resemble actual model response surfaces are used to illustrate the concepts, and show VARS to be as much as two orders of magnitude more computationally efficient than the state‐of‐the‐art Sobol approach. In a companion paper, we propose a practical implementation strategy, and demonstrate the effectiveness, efficiency, and reliability (robustness) of the VARS framework on real‐data case studies.
Continuous Optimization by Variable Neighborhood Search
Authors: Brimberg Jack , Hansen Pierre , MladenoviĆ Nenad
Published: December 2015

Variable neighborhood search (VNS) is a metaheuristic for solving optimization problems, whose basic idea is a systematic change of neighborhood structures in the search for a better solution. During the last 15 years, many variants of VNS have been proposed. In this section, we first describe basic VNS procedures and then discuss some recent extensions for solving continuous global optimization problems.
Influence of Twin Thickness and Grain Size on the Tensile Behavior of Fully Nanotwinned CuAl Alloys
Authors: Heckman Nathan M. , Velasco Leonardo , Hodge Andrea M.
Published: December 2015

In this study, the mechanical properties of fully nanotwinned Cu–2 wt%Al and Cu–6 wt%Al are evaluated by tension testing utilizing digital image correlation, allowing for the observation of local macroscopic deformation. By individually varying twin thickness, grain size, and composition, the isolated effect of each of these parameters on both strength and ductility is observed. Increased strength correlated with decreasing grain size or increasing Al content. It is observed that with decreasing twin thickness the ductility could be improved.
Virtual reconstruction of the Early Pleistocene mandible ATD6‐96 from Gran Dolina‐TD6‐2 (Sierra De Atapuerca, Spain)
Authors: Bermúdez de Castro José María , Martín‐Francés Laura , Modesto‐Mata Mario , Martínez de Pinillos Marina , Martinón‐Torres María , García‐Campos Cecilia , Carretero José Miguel
Published: December 2015

Objectives

In this report, we present a further study of the late Early Pleistocene ATD6‐96 human mandible, recovered from the TD6‐2 level of the Gran Dolina cave site (Sierra de Atapuerca, northern Spain) and attributed to Homo antecessor.

Methods

ATD6‐96 consists of a left half of a gracile mandible of an adult individual with the premolars and molars in place that is broken at the level of the lateral incisor‐canine septum. The present analysis is based on a virtual reconstruction of the whole mandible by means of computed tomography (CT). We have reconstructed the symphysis using information from a modern human sample, as well as from a wide sample composed of several Homo specimens.

Results

This research has allowed us to record new variables with taxonomic and phylogenetic interest. We have estimated the length/width index of the alveolar arcade, as well as the percentage of the arcade length with regard to the total length. The latter confirms that ATD6‐96 shares with all African and Asian Homo species a primitive structural pattern, as it was established in previous studies. In constrast, the length/width index of the alveolar arcade in the H. antecessor specimen is close to the mean values of Neandertals and the Atapuerca‐Sima de los Huesos hominins.

Conclusions

H. antecessor is derived regarding the shape of the mandibular alveolar arcade within the genus Homo and points to an early divergence from contemporaneous African populations. Our results also ratify the affinities of H. antecessor with Neanderthals, although the precise relationship with this lineage needs further research. Am J Phys Anthropol 159:729–736, 2016. © 2015 Wiley Periodicals, Inc.
Rapid and Efficient Separation of Oil from Oil‐in‐Water Emulsions Using a Janus Cotton Fabric
Authors: Wang Zijie , Wang Yu , Liu Guojun
Published: December 2015

A novel bi‐functional Janus cotton fabric is used to separate oil from oil‐in‐water emulsions. This fabric is superhydrophobic on one surface and polyamine‐bearing on the other. When used as a filter, the polyamine‐bearing side causes the micrometer‐sized oil droplets to coalesce. The coalesced oil then fills fabric pores on the superhydrophobic side and selectively permeates it. Oil separation using this method is rapid and the separated oil is pure. Furthermore, the content of the model oil hexadecane (HD) in water after a separation can be reduced to less than 0.03±0.03 vol %. These features demonstrate the practical potential of this technology.
Accelerating Oxygen‐Reduction Catalysts through Preventing Poisoning with Non‐Reactive Species by Using Hydrophobic Ionic Liquids
Authors: Zhang Gui‐Rong , Munoz Macarena , Etzold Bastian J. M.
Published: December 2015

Developing cost‐effective electrocatalysts for the oxygen reduction reaction (ORR) is a prerequisite for broad market penetration of low‐temperature fuel cells. A major barrier stems from the poisoning of surface sites by nonreactive oxygenated species and the sluggish ORR kinetics on the Pt catalysts. Herein we report a facile approach to accelerating ORR kinetics by using a hydrophobic ionic liquid (IL), which protects Pt sites from surface oxidation, making the IL‐modified Pt intrinsically more active than its unmodified counterpart. The mass activity of the catalyst is increased by three times to 1.01 A mg−1Pt@0.9 V, representing a new record for pure Pt catalysts. The enhanced performance of the IL‐modified catalyst can be stabilized after 30 000 cycles. We anticipate these results will form the basis for an unprecedented perspective in the development of high‐performing electrocatalysts for fuel‐cell applications.
ɛ‐TiO, a Novel Stable Polymorph of Titanium Monoxide
Authors: Amano Shinsaku , Bogdanovski Dimitri , Yamane Hisanori , Terauchi Masami , Dronskowski Richard
Published: December 2015

For the Ti/O system, three titanium monoxide (TiO) phases (α, β, and γ) with defective NaCl‐type structures and a high‐temperature hexagonal phase (H) have been known for decades. In this work, single crystals of a novel polymorph, ɛ‐TiO, were synthesized by using a bismuth flux. X‐ray diffraction (XRD) revealed a hexagonal crystal structure (a=4.9936(3) Å, c=2.8773(2) Å, P
2m) that is isotypic with ɛ‐TaN. While the Ti atoms are surrounded by trigonal prismatic (sixfold coordination) and trigonal planar (threefold coordination) arrangements of O atoms, the O atoms are found in a pseudo‐square‐pyramidal arrangement of Ti atoms. First‐principles calculations of the formation enthalpy and the electron and phonon density of states and crystal orbital Hamilton population (COHP) analysis revealed that ɛ‐TiO is more stable than α‐TiO, which had previously been regarded as the most stable phase at low temperatures.
Synergistic improvement of thermal transport properties for thermoplastic composites containing mixed alumina and graphene fillers
Authors: Yu Wei , Qi Yu , Zhou Yuan , Chen Lifei , Du Haixu , Xie Huaqing
Published: December 2015

In this work, a novel approach was developed for obtaining a strong three‐dimensional network of heat conducting path by filling alumina (Al2O3) and graphene sheets (GR) into poly(ethylene‐co‐vinyl acetate) (EVA). This unique structure effectively prevents the inter‐sheet restacking of graphene sheets and minimizes the thermal contact resistance between fillers and interface. The resultant exhibits a high thermal conductivity of 2.40 ± 0.07 W/m K, which is much higher than single filler at the same loading. Additionally, a strong synergistic effect can also be observed, and three‐dimensional schematic models were simulated for this enhancement. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43242.
Investigation and modelling of damping mechanisms of magnetorheological elastomers
Authors: Shuib Raa Khimi , Pickering Kim Louise
Published: December 2015

Damping in MREs is considered to be ascribed to viscous flow of the rubber matrix, interfacial damping at the interface between the magnetic particles and the matrix and magnetism induced damping. In this study, individual components in MREs that contribute to material damping were investigated. A model was developed to include viscous flow of the rubber matrix, interfacial damping and magnetism induced damping to give the total damping capacity of MREs()It was found thatdepends on frequency, iron sand content, strain amplitude andis independent of the applied magnetic field over saturation magnetization. The proposed model was assessed experimentally using a series of isotropic and anisotropic MREs. Comparison between tan δ withshowed thatmatched the experimental trends with average percentage difference of 8.1% and 21.8% for MREs with modified iron sand unmodified iron sand, respectively. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2016,133, 43247.
The anatomy ofE‐Learning tools: Does software usability influence learning outcomes?
Authors: Van Nuland Sonya E. , Rogers Kem A.
Published: December 2015

Reductions in laboratory hours have increased the popularity of commercial anatomy e‐learning tools. It is critical to understand how the functionality of such tools can influence the mental effort required during the learning process, also known as cognitive load. Using dual‐task methodology, two anatomical e‐learning tools were examined to determine the effect of their design on cognitive load during two joint learning exercises. A.D.A.M. Interactive Anatomy is a simplistic, two‐dimensional tool that presents like a textbook, whereas Netter's 3D Interactive Anatomy has a more complex three‐dimensional usability that allows structures to be rotated. It was hypothesized that longer reaction times on an observation task would be associated with the more complex anatomical software (Netter's 3D Interactive Anatomy), indicating a higher cognitive load imposed by the anatomy software, which would result in lower post‐test scores. Undergraduate anatomy students from Western University, Canada (n = 70) were assessed using a baseline knowledge test, Stroop observation task response times (a measure of cognitive load), mental rotation test scores, and an anatomy post‐test. Results showed that reaction times and post‐test outcomes were similar for both tools, whereas mental rotation test scores were positively correlated with post‐test values when students used Netter's 3D Interactive Anatomy (P = 0.007), but not when they used A.D.A.M. Interactive Anatomy. This suggests that a simple e‐learning tool, such as A.D.A.M. Interactive Anatomy, is as effective as more complicated tools, such as Netter's 3D Interactive Anatomy, and does not academically disadvantage those with poor spatial ability. Anat Sci Educ 9: 378–390. © 2015 American Association of Anatomists.
Phase‐locked tropical Pacific precipitation
Authors: Curtis Scott , Douglass David H.
Published: December 2015

Prior studies of the El Niño/La Niña index SST3.4 showed periodicity of exactly 2 or 3 years which were ‘phase‐locked’ to the annual solar cycle. Ten such phase‐locked intervals since 1870 were found. This article extends this work by studying precipitation data (P34) for the same region. We find phase‐locked segments corresponding to those found in SST3.4. Each segment agrees both in the period of oscillation and the date interval. However, the temperature‐precipitation relationship changes from segment to segment, demonstrating the non‐stationarity of the system. The beginnings and ends of these time segments agree with previously reported abrupt climate shifts.