bluuebunny/crossref_metadata_2025 huggingface dataset:
The International Reference Ionosphere: Rawer's IRI and its status today
Authors: Bilitza D.
Published: November 2014

Abstract. When the Committee on Space Research (COSPAR) initiated the International Reference Ionosphere (IRI) project in 1968 it wisely selected K. Rawer as its first Chairperson. With a solid footing and good contacts in both the ground-based and space-based ionospheric communities he was ideally suited to pull together colleagues and data from both communities to help build the first version of the IRI. He assembled a team of 20+ international ionospheric experts in the IRI Working Group and chaired and directed the group from 1968 to 1984. The working group has now grown to 63 members and the IRI model has undergone many revisions as new data became available and new modeling techniques were applied. This paper was presented during a special session of the Kleinheubach Tagung 2013 in honor of K. Rawer's 100th birthday. It will review the current status of the IRI model and project and the international recognition it has achieved. It is quite fitting that this year we not only celebrate K. Rawer's 100th birthday but also the exciting news that his favorite science endeavor, IRI, has been internationally recognized as an ISO (International Standardization Organization) standard. The IRI homepage is at http://irimodel.org.
Remote sensing and modeling of lightning caused long recovery events within the lower ionosphere using VLF/LF radio wave propagation
Authors: Schmitter E. D.
Published: November 2014

Abstract. On the 4 November 2012 at 3:04:27 UT a strong lightning in the midst of the North Sea affected the propagation conditions of VLF/LF transmitter radio signals from NRK (Iceland, 37.5 kHz) and GBZ (UK, 19.58 kHz) received at 5246° N 8° E (NW Germany). The amplitude and phase dips show a recovery time of 6–12 min pointing to a LOng Recovery Early VLF (LORE) event. Clear assignment of the causative return stroke in space and time was possible with data from the WWLLN (Worldwide Lightning Location Network). Based on a return stroke current model the electric field is calculated and an excess electron density distribution which decays over time in the lower ionosphere is derived. Ionization, attachment and recombination processes are modeled in detail. Entering the electron density distribution in VLF/LF radio wave propagation calculations using the LWPC (Long Wavelength Propagation Capability) code allows to model the VLF/LF amplitude and phase behavior by adjusting the return stroke current moment. The results endorse and quantify the conception of lower ionosphere EMP heating by strong – but not necessarily extremely strong – return strokes of both polarities.
Probability of occurrence of planetary ionosphere storms associated with the magnetosphere disturbance storm time events
Authors: Gulyaeva T. L. , Arikan F. , Stanislawska I.
Published: November 2014

Abstract. The ionospheric W index allows to distinguish state of the ionosphere and plasmasphere from quiet conditions (W = 0 or ±1) to intense storm (W = ±4) ranging the plasma density enhancements (positive phase) or plasma density depletions (negative phase) regarding the quiet ionosphere. The global W index maps are produced for a period 1999–2014 from Global Ionospheric Maps of Total Electron Content, GIM-TEC, designed by Jet Propulson Laboratory, converted from geographic frame (−87.5:2.5:87.5° in latitude, −180:5:180° in longitude) to geomagnetic frame (−85:5:85° in magnetic latitude, −180:5:180° in magnetic longitude). The probability of occurrence of planetary ionosphere storm during the magnetic disturbance storm time, Dst, event is evaluated with the superposed epoch analysis for 77 intense storms (Dst ≤ −100 nT) and 230 moderate storms (−100 < Dst ≤ −50 nT) with start time, t0, defined at Dst storm main phase onset. It is found that the intensity of negative storm, iW-, exceeds the intensity of positive storm, iW+, by 1.5–2 times. An empirical formula of iW+ and iW- in terms of peak Dst is deduced exhibiting an opposite trends of relation of intensity of ionosphere-plasmasphere storm with regard to intensity of Dst storm.
Indoor radio channel modeling and mitigation of fading effects using linear and circular polarized antennas in combination for smart home system at 868 MHz
Authors: Wunderlich S. , Welpot M. , Gaspard I.
Published: November 2014

Abstract. The markets for smart home products and services are expected to grow over the next years, driven by the increasing demands of homeowners considering energy monitoring, management, environmental controls and security. Many of these new systems will be installed in existing homes and offices and therefore using radio based systems for cost reduction. A drawback of radio based systems in indoor environments are fading effects which lead to a high variance of the received signal strength and thereby to a difficult predictability of the encountered path loss of the various communication links. For that reason it is necessary to derive a statistical path loss model which can be used to plan a reliable and cost effective radio network. This paper presents the results of a measurement campaign, which was performed in six buildings to deduce realistic radio channel models for a high variety of indoor radio propagation scenarios in the short range devices (SRD) band at 868 MHz. Furthermore, a potential concept to reduce the variance of the received signal strength using a circular polarized (CP) patch antenna in combination with a linear polarized antenna in an one-to-one communication link is presented.
Error propagation in the computation of volumes in 3D city models with the Monte Carlo method
Authors: Biljecki F. , Ledoux H. , Stoter J.
Published: November 2014

Abstract. This paper describes the analysis of the propagation of positional uncertainty in 3D city models to the uncertainty in the computation of their volumes. Current work related to error propagation in GIS is limited to 2D data and 2D GIS operations, especially of rasters. In this research we have (1) developed two engines, one that generates random 3D buildings in CityGML in multiple LODs, and one that simulates acquisition errors to the geometry; (2) performed an error propagation analysis on volume computation based on the Monte Carlo method; and (3) worked towards establishing a framework for investigating error propagation in 3D GIS. The results of the experiments show that a comparatively small error in the geometry of a 3D city model may cause significant discrepancies in the computation of its volume. This has consequences for several applications, such as in estimation of energy demand and property taxes. The contribution of this work is twofold: this is the first error propagation analysis in 3D city modelling, and the novel approach and the engines that we have created can be used for analysing most of 3D GIS operations, supporting related research efforts in the future.
Wavevector anisotropy of plasma turbulence at ion kinetic scales: solar wind observations and hybrid simulations
Authors: Comişel H. , Narita Y. , Motschmann U.
Published: November 2014

Abstract. Wavevector anisotropy of ion-scale plasma turbulence is studied at various values of ion beta. Two complementary methods are used. One is multi-point measurements of magnetic field in the near-Earth solar wind as provided by the Cluster spacecraft mission, and the other is hybrid numerical simulation of two-dimensional plasma turbulence. Both methods demonstrate that the wavevector anisotropy is reduced with increasing values of ion beta. Furthermore, the numerical simulation study shows the existence of a scaling law between ion beta and the wavevector anisotropy of the fluctuating magnetic field that is controlled by the thermal or hybrid particle-in-cell simulation noise. Likewise, there is weak evidence that the power-law scaling can be extended to the turbulent fluctuating cascade. This fact can be used to construct a diagnostic tool to determine or to constrain ion beta using multi-point magnetic field measurements in space.
A Graduate Course on Teaching and Learning in Higher Education: Influences on Conceptions of Teaching and Learning
Authors: Leger Andrew B , Fostaty Young Sue
Published: November 2014

This paper reports on the effects of a graduate course on teaching and learning on graduate teaching assistants’ conceptions of teaching and on the teaching philosophy statements that arose from those conceptions. Effects are interpreted from three perspectives: 1) course facilitators' reports of their perceptions of course participants’ conceptual change; 2) an independent assessors' ratings of the evidence of change through blind review of course participants’ initial philosophy statements and final statements; and 3) participants' own perceptions of change and identification of the course components and learning activities that were most significant in their conceptual development. Findings suggest that graduate teaching assistants’ perceptions of conceptual change differ significantly from those of both the course facilitators and the independent assessor.
Cet article présente un rapport concernant les effets d’un cours supérieur portant sur l’enseignement et l’apprentissage sur les conceptions relatives à l’enseignement d’assistants d’enseignement diplômés et sur les exposés sur la philosophie d’enseignement qui ont découlé de ces conceptions. Les effets sont interprétés à partir de trois perspectives : 1) les rapports des facilitateurs du cours concernant leurs perceptions du changement conceptuel survenu parmi les participants; 2) l’évaluation d’un assesseur indépendant concernant l’évidence du changement par le biais d’un examen aveugle des exposés initiaux sur la philosophie d’enseignement des participants ainsi que de leurs exposés finaux; et 3) les perceptions personnelles des participants concernant le changement et l’identification des composantes du cours et des activités d’apprentissage qui ont été les plus significatives pour leur développement conceptuel. Les résultats suggèrent que les perceptions des assistants d’enseignement diplômés concernant le changement conceptuel diffèrent grandement de celles des facilitateurs du cours et de celles de l’assesseur indépendant.
Minimal Marking: A Success Story
Authors: McNeilly Anne
Published: November 2014

The minimal-marking project conducted in Ryerson’s School of Journalism throughout 2012 and early 2013 resulted in significantly higher grammar scores in two first-year classes of minimally marked university students when compared to two traditionally marked classes. The “minimal-marking” concept (Haswell, 1983), which requires dramatically more student engagement, resulted in more successful learning outcomes for surface-level knowledge acquisition than the more traditional approach of “teacher-corrects-all.” Results suggest it would be effective, not just for grammar, punctuation, and word usage, the objective here, but for any material that requires rote-memory learning, such as the Associated Press or Canadian Press style rules used by news publications across North America.
Le projet de corrections minimales mené à l’École de journalisme de Ryerson tout au long de 2012 et au début de 2013 a eu pour résultat des notes de grammaire considérablement supérieures dans deux classes de première année d’étudiants universitaires corrigés de façon minimale par rapport à deux classes où les étudiants étaient corrigés de façon traditionnelle. Le concept de « corrections minimales » (Haswell, 1983), qui exige un engagement considérablement plus important de la part des étudiants, aboutit à des résultats d’apprentissage supérieurs en ce qui concerne l’acquisition de connaissances au niveau superficiel par rapport à l’approche traditionnelle du « professeur qui corrige tout ». Les résultats suggèrent que cette approche serait efficace, non seulement pour la grammaire, la ponctuation et le bon usage des mots, qui étaient l’objectif visé dans ce cas, mais également pour n’importe quelle matière qui exige un apprentissage par mémorisation, tel que les règles de style de la Associated Press ou de la Presse canadienne utilisées par les publications de presse d’un bout à l’autre du Canada.
Case Report: Postradiation Chondrosarcoma with a Short Latency Period of 6 Months
Authors: Yang Sen , Tang Wei , Tang Xiu-fa , Xuan Ming , Guo Li-juan , Wang Xiao-yi , Loo Wings TY , Liu Qing , Chow Louis WC , Cheung Mary NB , Tsang William
Published: November 2014

We describe a case of postradiation chondrosarcoma after basal cell carcinoma treatment. At the time he presented, the patient was a 35-year-old man who had received radiotherapy at a dose of 70 Gy for 8 weeks. Six months after radiation treatment, a rapidly growing mass at the upper right alveolar ridge of the gums, where radiation had been given, was diagnosed as chondrosarcoma. Generally, chondrosarcoma occurs after a latency period of several years following radiation. However, there are a few relevant reports indicating that maxillofacial chondrosarcoma can develop after radiotherapy for basal cell carcinoma, with a short latency of 6 months. We hypothesize that the dosage and treatment time of radiation may have played a role in the opening/closing of the Hh-signaling pathway in the case of this patient.
Neutrophils in atherosclerosis
Authors: Roig C. , Daemen M. , Lutgens E. , Soehnlein O. , Hartwig H.
Published: November 2014

Atherosclerosis is a chronic inflammation of the arterial wall and the continuous infiltration of leukocytes into the plaque enhances the progression of the lesion. Because of the scarce detection of neutrophils in atherosclerotic plaques compared to other immune cells, their contribution was largely neglected. However, in the last years studies have accumulated pointing towards the contribution of neutrophils to atherogenesis. In addition, studies are emerging implying a role for neutrophils in advanced atherosclerosis and/or plaque destabilization. Thus, this brief review delivers an overview of the role of neutrophils during early and late stage atherosclerosis.
Amphotericin B-Deoxycholate is as Effective and Safe as the Costly Amphotericin B Colloidal Dispersion in the Treatment of Paediatric Invasive Fungal Infections
Authors: Sarinah Tamring  , Tey Ie Lane  , Hani Syazwani Mohd Shah  , Harikrishnan Shanmuganathan  , Tzar Mohd Nizam Khaithir  , Ahmad Nazrun Shuid  , Boekhtiar Borhanuddin  , Isa Naina Mohamed
Published: November 2014

Amphotericin B deoxycholate (AmBD) and amphotericin B colloidal dispersion (AmBCD) are the two most commonly used antifungals for invasive fungal infections (IFI) among paediatric patients. The objective of this pilot study was to compare the efficacy, adverse effects and cost-effectiveness between AmBD and AmBCD in the treatment of IFI among paediatric patients admitted at Universiti Kebangsaan Malaysia Medical Centre (UKMMC).Methods: Secondary data analysis of the medical records of all paediatric patients with IFI was obtained and data extraction was performed for patients admitted between July 1, 2006 and June 30, 2011. Efficacy of treatment was determined and reports of adverse effects were noted.Results: Between July 1, 2006 and June 30, 2011, thirty-five patients received AmBD-only treatment and five patients received AmBCD-only treatment. Twenty-four patients were males and the mean age was 7.18 (SD 4.59) years. On average, the AmBCD treatment course was significantly more expensive than AmBD (p
Improvement of Weight and Body Composition in a Group of Women through a Weight Management Program Using Food Supplements with or without a Hypocaloric Diet
Authors: Magdalena Rafecas  , Laura-Isabel Arranz  , Mireia García  , Miguel-Ángel Canela  , DIECA Group
Published: November 2014

Overweight is an increasing health problem characterised as a higher than normal body weight due to an abnormal increase in body fat. Body weight adequacy is categorized by using body mass index (BMI), however other parameters such as fat mass (FM), waist circumference (Wci) or waist to hip ratio, are relevant. Ideally, body composition should be calculated initially to evaluate changes during a dietary intervention of weight loss. Hunger experience is another parameter to take into account. The aim of this study was to assess the improvement of weight and body composition through the use of food supplements to control hunger, with and without a hypocaloric diet prescription. 252 women who wanted to lose weight were recruited in the program and splitted into two groups and were monitored for 8 weeks. Anthropometric measures (weight, height, body mass index, fat mass, waist and hip circumference) were taken. The mean age was of 36.84±7.29 and most of them were within overweight or obesity values for BMI, FM, Wci and hip circumference. After 8 weeks, both groups got significant results, achieving not only weight loss but also reduction in body mass index, fat mass, and waist and hip circumferences. However, as expected, improvements were better in FS+diet than in FS group. There is a need to tackle overweight and obesity individually, taking into account the personal characteristics of the patient. Food supplements may be useful to manage hunger and professional individualised assessment is critical to succeed.
Where and when will we observe cloud changes due to climate warming?
Authors: Chepfer H. , Noel V. , Winker D. , Chiriaco M.
Published: November 2014

Climate models predict that the geographic distribution of clouds will change in response to anthropogenic warming, though uncertainties in the existing satellite record are larger than the magnitude of the predicted effects. Here we argue that cloud vertical distribution, observable by active spaceborne sensors, is a more robust signature of climate change. Comparison of Atmospheric Model Intercomparison Project present day and +4 K runs from Coupled Model Intercomparison Project Phase 5 shows that cloud radiative effect and total cloud cover do not represent robust signatures of climate change, as predicted changes fall within the range of variability in the current observational record. However, the predicted forced changes in cloud vertical distribution (directly measurable by spaceborne active sensors) are much larger than the currently observed variability and are expected to first appear at a statistically significant level in the upper troposphere, at all latitudes.
A storm in a shelf sea: Variation in phosphorus distribution and organic matter stoichiometry
Authors: Davis Clare E. , Mahaffey Claire , Wolff George A. , Sharples Jonathan
Published: November 2014

Organic matter (OM) plays an important role in productive shelf seas and their contribution to global carbon (C) and nutrient cycles. We investigated the impact of storm mixing on OM dynamics in the seasonally stratified Celtic Sea. After the storm, OM production was decoupled from consumption in the euphotic layer. Over the 15 day study, dissolved OM (DOM) became phosphorus (P) rich relative to C, whereas particulate OM (POM) became P‐deplete relative to C. Upward diapycnal phosphate fluxes were accompanied by reciprocal downward mixing of dissolved organic P (DOP) and particulate P (PPhos). Transfer of DOP and PPhos below the thermocline accounts for 22% and 26%, respectively, of the upward phosphate flux. Given the changes in stoichiometry of POM and DOM after the storm, the form in which OM is transferred below the thermocline has important implications for the efficiency of elemental transfer, impacting C cycling and storage in the ocean.
Man‐induced low‐frequency seismic events in Italy
Authors: Latorre Diana , Amato Alessandro , Cattaneo Marco , Carannante Simona , Michelini Alberto
Published: November 2014

Unconventional seismic events in Italy are detected by scanning three years of continuous waveforms recorded by the Italian National Seismic Network. Cross correlation of signal templates with continuous seismic records has evidenced unusual events with similar low‐frequency characteristics in several Italian regions. Spectral analysis and spatiotemporal distribution of these events, some of which are previously interpreted as tectonic long‐period transients, suggest that they are not natural, but produced by huge cement factories. Since there are at least 57 full‐cycle cement plants operating in Italy, each affecting areas of about 1250 to 2800 km2, we argue that significant portions of the Italian territory (23% to 51%) can be affected by this man‐made noise. Seismic noise analyses, such as those used for microzonation or crustal structure investigations, as well as data mining techniques used to retrieve anomalous transient signals, should thus take into account this peculiar and pervasive source of seismic waves.
The magnitudes of the regions 1 and 2 Birkeland currents observed by AMPERE and their role in solar wind‐magnetosphere‐ionosphere coupling
Authors: Coxon J. C. , Milan S. E. , Clausen L. B. N. , Anderson B. J. , Korth H.
Published: November 2014

In this paper we present the first large‐scale statistical study of the influence of magnetic reconnection on the magnitude of the regions 1 and 2 Birkeland field‐aligned currents (FACs). While previous studies have employed single spacecraft measurements to construct a statistical picture of the location and density of the Birkeland currents, it has hitherto been difficult to compare in situ measurements of the solar wind with instantaneous global field‐aligned current measurements. To that end, we utilize the Active Magnetosphere Planetary Electrodynamics Response Experiment (AMPERE), which yields field‐aligned current density in both hemispheres at a cadence of 10 min. We quantify the amount of current flowing in the regions 1 (R1) and 2 (R2) FACs, and we compare these with the dayside reconnection rate ΦD deduced from interplanetary parameters from the OMNI data set and with the AL index to examine whether magnetic reconnection is responsible for driving currents in the coupled magnetosphere‐ionosphere system. We find that current magnitudes are strongly correlated with both ΦD and AL index. We also find that R1 currents tend to be higher than R2 currents during periods of magnetic reconnection, suggesting leakage of current across the polar cap or an association with the substorm current wedge.
Exploring remote earthquake triggering potential across EarthScopes' Transportable Array through frequency domain array visualization
Authors: Linville Lisa , Pankow Kristine , Kilb Debi , Velasco Aaron
Published: November 2014

To better understand earthquake source processes involved in dynamically triggering remote aftershocks, we use data from the EarthScope Transportable Array (TA) that provide uniform station sampling, similar recording capabilities, large spatial coverage, and, in many cases, repeat sampling at each site. To avoid spurious detections, which are an inevitable part of automated time domain amplitude threshold detection methods, we develop a frequency domain earthquake detection algorithm that identifies coherent signal patterns through array visualization. This method is tractable for large data sets, ensures robust catalogs, and delivers higher resolution observations than what are available in current catalogs. We explore seismicity rate changes local to the TA stations following 18 global main shocks (M ≥ 7) that generate median peak dynamic stress amplitudes of 0.001–0.028 MPa across the array. From these main shocks, we find no evidence of prolific or widespread remote dynamic triggering in the continental U.S. within the main shock's wave train or following main shock stress transients within 2 days. However, limited evidence for rate increases exist in localized source regions. These results suggest that for these data, prolific, remote earthquake triggering is a rare phenomenon throughout a wide range of observable magnitudes. We further conclude that within the lower range of previously reported triggering thresholds, surface wave amplitude does not correlate well with observed cases of dynamic triggering. We propose that other characteristics of the triggering wavefield, in addition to specific conditions at the site, will drive the occurrence of triggering at these amplitudes.
Effects of temperature and CO2 on the frictional behavior of simulated anhydrite fault rock
Authors: Pluymakers Anne M.H. , Samuelson Jon E. , Niemeijer André R. , Spiers Christopher J.
Published: November 2014

The frictional behavior of anhydrite‐bearing faults is of interest to (a) the safety and effectiveness of CO2 storage in anhydrite‐capped reservoirs, (b) seismicity induced by hydrocarbon production, and (c) natural seismicity nucleated in evaporite formations. We performed direct shear experiments on simulated anhydrite fault gouges, at a range of temperatures (80–150°C) and sliding velocities (0.2–10 µm s−1), under a fixed effective normal stress of 25 MPa. Four types of experiments were conducted (1) dry experiments, (2) experiments pressurized with water, (3) dry experiments pressurized with CO2, and (4) wet experiments pressurized with CO2. Fluid pressures of 15 MPa were used when applied. Over the temperature range investigated water‐saturated samples were found to be up to 15% frictionally weaker than dry equivalents. Wet samples containing CO2 were also up to 15% weaker than CO2‐free equivalents. Dry sample strength without CO2 was independent of temperature, whereas wet samples without CO2 strengthened 10% from 80 to 150°C. Samples containing CO2 weakened by 4% (dry) and 10% (wet) from 80 to 150°C. Under the P‐T conditions investigated, only dry anhydrite fault gouge showed velocity‐weakening behavior above 120°C, required for faults to potentially generate earthquakes. Assuming natural fault gouges are wet in situ, seismicity is unlikely to nucleate in anhydrite‐rich faults, though the presence of dolomite or (reaction‐produced) calcite may change seismic potential. CO2 penetration into wet anhydrite‐rich faults may trigger slip on critically stressed faults due to the observed short‐term CO2 weakening effects (excluding possible formation of secondary minerals), but is not expected to influence slip stability.
Accuracy of ground surface broadband shortwave radiation monitoring
Authors: Vuilleumier L. , Hauser M. , Félix C. , Vignola F. , Blanc P. , Kazantzidis A. , Calpini B.
Published: November 2014

The uncertainty of broadband shortwave radiation monitoring is determined for direct, diffuse, and global irradiance for measurements obtained at the Payerne (Switzerland) station of the Baseline Surface Radiation Network (BSRN). The uncertainty estimates include sources that reflect realistic long‐term operation conditions. The uncertainties are derived using the methodology specified by the “Guide to the expression of uncertainty in measurement.” The differences between redundant determinations of direct, diffuse, and global irradiance are analyzed and are shown to be compatible with the uncertainties. In addition, the signatures of some uncertainty sources are sought within the error statistics to find out if corrections can be applied and what their magnitude is. The global and diffuse irradiance uncertainties range from 1.8% to 2.4% without correction and are less than 1.8% with corrections. These uncertainties are close to or satisfy the BSRN targets for large signals (global: 1000 W m−2, diffuse: 500 W m−2). For small signals (50 W m−2), the targets are not achieved, mainly as a result of uncertainties associated with the data acquisition electronics (DAQ). The direct irradiance uncertainty is ~1.5%, 3 times larger than the BSRN uncertainty target. An accuracy gain can also be achieved at the DAQ level, but even without considering the DAQ uncertainty, the target is exceeded by a factor of about 2. The direct irradiance uncertainty remains ~1% even using an absolute cavity radiometer as transfer standard for correcting the pyrheliometer sensitivity. Thus, the direct irradiance accuracy target of 0.5% is probably not achievable with the best commercially available technology.
Application of the Schumann resonance spectral decomposition in characterizing the main African thunderstorm center
Authors: Dyrda Michał , Kulak Andrzej , Mlynarczyk Janusz , Ostrowski Michał , Kubisz Jerzy , Michalec Adam , Nieckarz Zenon
Published: November 2014

In this paper we present a new method for quantifying the main tropical thunderstorm regions based on extremely low frequency (ELF) electromagnetic wave measurements from a single station—the Hylaty ELF station in Central Europe. Our approach is based on Schumann resonance (SR) measurements, which we apply as an example to thunderstorms in Africa. By solving the inverse problem, using the SR power spectrum templates derived analytically, we calculate distances to the most powerful thunderstorm centers and present simplified 1‐D thunderstorm lightning activity “maps” in absolute units C2m2/s. We briefly describe our method of SR power spectrum analysis and present how this method is used with real observational data. We obtained the monthly lightning activity maps of the African storm centers with a spatial resolution of 1° and temporal resolution of 10 min for January and August 2011. This allowed us to study the varying location and intensities of the African storm centers in different seasons of the year. A cross check of the obtained lightning activity maps with Tropical Rainfall Measuring Mission satellite data recorded by the Lightning Imaging Sensor and the derived correlation coefficients between SR and optical data were used to validate the proposed method. We note that modeling a maximum possible number of resonance modes in the SR power spectra (in our case, seven resonances) is essential in application of the proposed approach.
Lanthanide‐Doped Fluoride Core/Multishell Nanoparticles for Broadband Upconversion of Infrared Light
Authors: Shao Wei , Chen Guanying , Ohulchanskyy Tymish Y. , Kuzmin Andrey , Damasco Jossana , Qiu Hailong , Yang Chunhui , Ågren Hans , Prasad Paras N.
Published: November 2014

The authors introduce a novel multilayer core/shell design to broadly upconvert infrared (IR) light at many discrete wavelengths into visible or near‐IR (NIR) emissions. It utilizes hexagonal‐phase core/multishell NaYF4:10%Er3+@NaYF4@NaYF4:10%Ho3+@NaYF4@NaYF4:1%Tm3+@NaYF4 nanoparticles, where the active core as well as each active shell upconvert a distinct set of IR wavelength. The inert NaYF4 layers in between these upconverting domains efficiently suppress the detrimental cross‐relaxation processes between different types of lanthanide ions, thus yielding about two times more efficient upconversion photoluminescence than the counterpart NaYF4:10%Er3+@NaYF4:10%Ho3+ @NaYF4:1%Tm3+@NaYF4 without the inert NaYF4 layers, and about one order of magnitude higher than the core/shell NaYF4:10%Er3+, 10%Ho3+, 1%Tm3+@NaYF4 nanoparticles without spatially isolating the Er3+, Ho3+, and Tm3+ ions. These core/multishell nanoparticles can be excited at ≈1120–1190 nm (due to Ho3+), ≈1190–1260 nm (due to Tm3+), and ≈1450–1580 nm (due to Er3+), collectively covering a broad spectral range of about 270 nm in the IR range that can be very useful for IR photosensitization of solar cells.
Exploration of the Effective Location of Surface Oxygen Defects in Graphene‐Based Electrocatalysts for All‐Vanadium Redox‐Flow Batteries
Authors: Park Minjoon , Jeon In‐Yup , Ryu Jaechan , Baek Jong‐Beom , Cho Jaephil
Published: November 2014

Oxygen functional groups play a key role in vanadium redox reactions. To identify the effective location of oxygen functionalities in graphene‐based nanomaterials, a selectively edge‐functionalized graphene nanoplatelet (E‐GnP) with a crystalline basal plane is produced by a ball‐milling process in the presence of dry ice. For comparison, the reduced graphene oxide (rGO) that contains defects at both edges and in the basal plane is produced by a modified Hummers' method. The location of defects in the graphene‐based nanomaterials significantly affects the electrocatalytic activity towards vanadium redox couples (V2+/V3+ and VO2+/VO2
+). The improved activity of these nanoplatelets lies in the presence of oxygen defects at the edge sites and higher crystallinity of basal planes than in rGO. This effective location of oxygen defects facilitates fast electron‐transfer and mass‐transport processes.
CO2 removal by single and mixed amines in a hollow‐fiber membrane module—investigation of contactor performance
Authors: Iliuta Ion , Bougie Francis , Iliuta Maria C.
Published: November 2014

This work investigates CO2 removal by single and blended amines in a hollow‐fiber membrane contactor (HFMC) under gas‐filled and partially liquid‐filled membrane pores conditions via a two‐scale, nonisothermal, steady‐state model accounting for CO2 diffusion in gas‐filled pores, CO2 and amines diffusion/reaction within liquid‐filled pores and CO2 and amines diffusion/reaction in liquid boundary layer. Model predictions were compared with CO2 absorption data under various experimental conditions. The model was used to analyze the effects of liquid and gas velocity, CO2 partial pressure, single (primary, secondary, tertiary, and sterically hindered alkanolamines) and mixed amines solution type, membrane wetting, and cocurrent/countercurrent flow orientation on the HFMC performance. An insignificant difference between the absorption in cocurrent and countercurrent flow was observed in this study. The membrane wetting decreases significantly the performance of hollow‐fiber membrane module. The nonisothermal simulations reveal that the hollow‐fiber membrane module operation can be considered as nearly isothermal. © 2014 American Institute of Chemical Engineers AIChE J, 61: 955–971, 2015
Application of polyethylenimine‐impregnated solid adsorbents for direct capture of low‐concentration CO2
Authors: Wang Jitong , Wang Mei , Li Wencheng , Qiao Wenming , Long Donghui , Ling Licheng
Published: November 2014

A systematic study of CO2 capture on the amine‐impregnated solid adsorbents is carried out at CO2 concentrations in the range of 400–5000 ppm, relating to the direct CO2 capture from atmospheric air. The commercially available polymethacrylate‐based HP2MGL and polyethylenimine are screened to be the suitable support and amine, respectively, for preparation of the adsorbent. The adsorbents exhibit an excellent saturation adsorption capacity of 1.96 mmol/g for 400 ppm CO2 and 2.13 mmol/g for 5000 ppm CO2. Moisture plays a promoting effect on CO2 adsorption but depends on the relative humidity. The presence of O2 would lead to the decrease of adsorption capacity but do not affect the cyclic performance. The diffusion additive is efficient to improve the adsorption capacity and cyclic performance. Moreover, the adsorbents can be easily regenerated under a mild temperature. This study may have a positive impact on the design of high‐performance adsorbents for CO2 capture from ambient air. © 2014 American Institute of Chemical Engineers AIChE J, 61: 972–980, 2015
Isotopic evidence for divergent diets and mobility patterns in the Atacama Desert, northern Chile, during the Late Intermediate Period (AD 900–1450)
Authors: Santana‐Sagredo Francisca , Lee‐Thorp Julia A. , Schulting Rick , Uribe Mauricio
Published: November 2014

The decline of the Tiwanaku state saw the emergence of two new cultures—Pica‐Tarapacá and Atacama—during the Late Intermediate Period in northern Chile. Archeological evidence suggests that both groups practised maize agriculture and pastoralism, but that their interaction zones differed significantly. Marine resources are common at Pica‐Tarapacá sites, even those far from coast, while Atacama sites in the desert oases and precordilleran area seem to have directed their networks towards the highlands. Here we apply stable carbon, nitrogen, and oxygen isotope analysis on human bone and enamel to test dietary patterns and residential mobility at two sites, Pica 8 and Quitor 6, representing the Pica‐Tarapacá and Atacama cultures, respectively. Our results show that diet at the two sites indeed differed: significant but variable consumption of marine resources and maize is indicated at Pica 8, despite being an inland site, while diet at Quitor 6 was based mainly on terrestrial resources. The use of seabird guano and llama dung as fertilizers and extreme aridity may have contributed to the high nitrogen isotope values observed in Pica 8 humans. The δ18O values in Pica 8 individuals are generally lower than for Quitor in spite of its greater distance from the Andes. All three isotopes suggest the presence of at least five nonlocals in the 30 measured at Pica 8. This evidence for human mobility is consistent with the high levels of trade and interaction observed in the archeological record, and begins to quantify the degree of movement of specific individuals. Am J Phys Anthropol 156:374–387, 2015. © 2014 Wiley Periodicals, Inc.
Green‐Solvent‐Processed Molecular Solar Cells
Authors: Chen Xiaofen , Liu Xiaofeng , Burgers Mark A. , Huang Ye , Bazan Guillermo C.
Published: November 2014

High‐efficiency bulk heterojunction (BHJ) organic solar cells with power conversion efficiencies of more than 5 % can be fabricated using the green solvent 2‐MeTHF. The active layers comprise a blend of a molecular semiconductor donor with intermediate dimensions (X2) and the soluble fullerene derivative [6,6]‐phenyl‐C61‐butyricacidoctylester (PC61BC8). A switch of the processing solvent from chloroform to 2‐MeTHF leads to no negative impacts on the morphology and charge‐transport properties of optimally performing BHJ films. Examinations by absorption spectroscopy, atomic force microscopy, and grazing incidence wide‐angle X‐ray scattering reveal no significant modification of morphology. These results show that green solvents can be excellent alternatives for large‐area printing of high‐performance organic photovoltaics (OPVs) and thus open new opportunities for sustainable mass production of organic solar cells and other optoelectronic devices.
Boron as a Powerful Reductant: Synthesis of a Stable Boron‐Centered Radical‐Anion Radical‐Cation Pair
Authors: Bissinger Philipp , Braunschweig Holger , Damme Alexander , Hörl Christian , Krummenacher Ivo , Kupfer Thomas
Published: November 2014

Despite the fundamental importance of radical‐anion radical‐cation pairs in single‐electron transfer (SET) reactions, such species are still very rare and transient in nature. Since diborenes have highly electron‐rich BB double bonds, which makes them strong neutral reductants, we envisaged a possible realization of a boron‐centered radical‐anion radical‐cation pair by SET from a diborene to a borole species, which are known to form stable radical anions upon one‐electron reduction. However, since the reduction potentials of all know diborenes (E1/2=−1.05/−1.55 V) were not sufficiently negative to reduce MesBC4Ph4 (E1/2=−1.69 V), a suitable diborene, IiPr⋅(iPr)BB(iPr)⋅IiPr, was tailor‐made to comply with these requirements. With a halfwave potential of E1/2=−1.95 V, this diborene ranks amongst the most powerful neutral organic reductants known and readily reacted with MesBC4Ph4 by SET to afford a stable boron‐centered radical‐anion radical‐cation pair.
Functionalization of hybrid poly(n‐isopropylacrylamide) hydrogels for Escherichia coli cell capture via adsorbed intermediate dye molecule
Authors: Gregory Jarod , Cannell Jonathon , Kofron Matthew , Yeghiazarian Lilit , Nistor Vasile
Published: November 2014

Poly(n‐isopropylacrylamide) Laponite (PNIPAM‐Lap) hybrid hydrogels, which use the synthetic clay Laponite as a crosslinker, permanently adsorb cationic laser dyes out of solution. This proof‐of‐concept expounds on this capability by adsorbing an intermediate dye molecule and using it as the foundation for successfully conjugating microbial antibodies to the surface of a PNIPAM hydrogel. The study involves using acriflavinium chloride molecules, adsorbed by a PNIPAM‐Lap hydrogel from an acriflavine laser dye solution, as an intermediate molecule to attach antibodies raised against E. coli to the hydrogel and demonstrate cell capture. Furthermore, this system exemplifies a novel biotechnological platform for greatly expanding PNIPAM hydrogels' capabilities and applicability through conjugation chemistry to surface‐bound molecules. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41557.
Preparation and characterization of MOF‐PES ultrafiltration membranes
Authors: Sotto Arcadio , Orcajo Gisela , Arsuaga Jesús María , Calleja Guillermo , Landaburu‐Aguirre Junkal
Published: November 2014

Fouling is one of the main disadvantages of membrane processes. Fouling can be mitigated by incorporating inorganic particles into the membrane. Composite membranes containing the inorganic fillers show higher pore size, porosity, and hydrophilic character than the neat PES membrane, which contributes to a better permeability. In this research, PES ultrafiltration membranes are prepared using both commercial and synthesized metal‐organic framework materials (MOF) as well as ZnO particles as fillers. Among the different fillers used, MOF particles produce a better effect on the permeability of the membrane than ZnO particles. The synthesized Zn/Co‐MOF‐74‐type materials have good structural stability in the polymeric matrix and the MOF‐PES membrane maintains its performance after a series of cycles of BSA water solution. Tested MOF‐PES membrane also shows higher BSA rejections and permeate flux than the neat PES membrane, demonstrating that it is possible to enhance the flux without losing the selectivity of the membrane. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41633.
Fracture toughness of carbon fiber/polyether ether ketone composites manufactured by autoclave and laser‐assisted automated tape placement
Authors: Ray Dipa , Comer Anthony J. , Lyons John , Obande Winifred , Jones David , Higgins Ronan M. O. , McCarthy Michael A.
Published: November 2014

A comparative study is presented on the fracture toughness of carbon fiber/PEEK composites manufactured by autoclave and laser‐assisted automated tape placement (LATP). Formation of a good inter‐laminar bond is always a concern in ATP due to the short time available for intimate contact development and polymer healing, yet our double cantilever beam (DCB) tests reveal 60–80% higher Mode I fracture toughness for the LATP processed specimens than for the autoclave processed specimens. This magnitude of difference was unexpected, so specimens were further examined via differential scanning calorimetry, dynamic mechanical analysis, nano‐indentation, and scanning electron microscopy. The results indicate that the LATP process has been very effective in heating and consolidating the surface of plies, creating an excellent bond. However, it has been less effective in processing the interior of plies, where a low crystallinity and poor fiber–matrix bonding are evident. The higher fracture toughness of the LATP processed specimens is also not solely due to a better bond, but is partially due to significant plastic deformation in the interior of plies during the DCB test. The findings indicate there is still considerable scope for optimizing the laser‐assisted ATP process, before the optimum balance between strength and toughness is achieved at favorable lay‐down speeds. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41643.
Antibacterial property on Gram‐positive bacteria of polypyrrole‐coated fabrics
Authors: Varesano Alessio , Vineis Claudia , Tonetti Cinzia , Mazzuchetti Giorgio , Bobba Vittorio
Published: November 2014

Antibacterial activity against Gram‐negative bacteria of polypyrrole‐coated fabrics has been demonstrated in the past. In this work, biocidal efficacy of polypyrrole has been evaluated against Gram‐positive bacteria on textiles with different polypyrrole loading. Excellent bacterial reduction (≥99%) was found on cotton fabrics containing more than ∼9 wt % of polypyrrole. Polypyrrole loading can be greatly reduced in presence of silver. Silver‐containing fabrics used in this work alone does not guarantee a complete biocidal effect, but the addition of just 2 wt % of polypyrrole showed a bacteria reduction of 99%. Moreover, stability to different washing procedures of the antibacterial activity was evaluated. Fabrics were characterized by scanning electron microscopy, energy dispersive X‐ray analysis, and infrared spectroscopy. Stability of the coating was assessed by abrasion tests. PPy showed excellent fastness to abrasion. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41670.
Preparation and characterization of grafting styrene onto LLDPE by cyclohexane compatibilization in suspension polymerization
Authors: Meng Fanyu , Zhang Qiaoyun , Wang Guozhi , Wang Hongyan , Gao Yan
Published: November 2014

A novel method of grafting styrene onto linear low‐density polyethylene (LLDPE) by suspension polymerization was systematically evaluated. Cyclohexane as a compatibilizer was introduced to swell and activate the surface of LLDPE molecular chain for amplifying the contact point of styrene monomer with LLDPE. A series of copolymer of grafting polystyrene (PS) onto LLDPE, known as LLDPE‐g‐PS, were prepared with different ratios of cyclohexane/styrene monomer and various LLDPE dosages. FTIR and 1H NMR techniques both confirmed successful PS grafting onto the LLDPE chains. In addition, SEM images of LLDPE‐g‐PS particles showed that the cross‐section morphology becomes smooth and dense with suitable cyclohexane dosages, indicating a better compatibility between LLDPE and PS. The highest grafting efficiency was 28.4% at 10 mL/g cyclohexane and styrene monomer when 8% LLDPE was added. In these conditions, the LLDPE‐g‐PS elongation at break increased by about 30 times compared with PS. Moreover, thermal gravimetric analysis (TGA) demonstrated that LLDPE‐g‐PS possesses much higher thermal stability than pure PS. Therefore, the optimal amount of cyclohexane as compatibilizer could increase the grafting efficiency and improve the toughness of PS. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41671.
Enzymatic Synthesis of a DNA Triblock Copolymer that is Composed of Natural and Unnatural Nucleotides
Authors: Mitomo Hideyuki , Watanabe Yukie , Matsuo Yasutaka , Niikura Kenichi , Ijiro Kuniharu
Published: November 2014

DNA molecules have come under the spotlight as potential templates for the fabrication of nanoscale products, such as molecular‐scale electronic or photonic devices. Herein, we report an enhanced approach for the synthesis of oligoblock copolymer‐type DNA by using the Klenow fragment exonuclease minus of E. coli DNA polymerase I (KF−) in a multi‐step reaction with natural and unnatural nucleotides. First, we confirmed the applicability of unnatural nucleotides with 7‐deaza‐nucleosides—which was expected because they were non‐metalized nucleotides—on the unique polymerization process known as the “strand‐slippage model”. Because the length of the DNA sequence could be controlled by tuning the reaction time, analogous to a living polymerization reaction on this process, stepwise polymerization provided DNA block copolymers with natural and unnatural bases. AFM images showed that this DNA block copolymer could be metalized sequence‐selectively. This approach could expand the utility of DNA as a template.
TP Model Transformation Via Sequentially Truncated Higher‐Order Singular Value Decomposition
Authors: Pan Junjun , Lu Linzhang
Published: November 2014

The sequentially truncated higher‐order singular value decomposition (ST‐HOSVD) is applied to a tensor product (TP) model transformation instead of the compact form of HOSVD (CHOSVD). The goal is to reduce computational cost in the transformation. By using the ST‐HOSVD, the TP model transformations of systems and the related algorithms are executed and the ST‐HOSVD based canonical form and the weighting functions are given. To see the effectiveness, we take a dynamic system and TORA system as numerical examples. A great reduction of complexity is seen in use of the ST‐HOSVD compared with use of the CHOSVD in TP model transformation. The approximation of the new method seems as good as the original one.