bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of CH3NH3PbI(3-x)Clx Perovskite Layer on the Performance of Inverted Type Hybrid Organic Solar Cells Based on ZnO/P3HT
Authors: Sabri Nasehah Syamin , Yap Chi Chin , Yahaya Muhammad , Salleh Muhamad Mat , Haji Jumali Mohammad Hafizuddin
Published: March 2016

This paper reports the effect of perovskite layer on enhancing the inverted type hybrid organic solar cell performance. The mixtures of methylammonium iodide (CH3NH3I) and lead (II) chloride (PbCl2) were dissolved in N,N-Dimethylformamide (DMF) solvent and was spin-coated onto fluorine-doped tin oxide (FTO) glass substrate coated with zinc oxide nanorod arrays (ZnONRAs). The poly (3-hexylthiophene-2,5-diyl) (P3HT) film was then spin-coated onto CH3NH3I(3-x)PbClx perovskite layer, followed by silver (Ag) deposition using magnetron sputtering technique. The FTO/ZnO seed/ZnONRAs/CH3NH3PbI(3-x)Clx /P3HT/Ag device was fabricated. A device without perovskite layer was also fabricated for comparison. A power conversion efficiency (PCE) of 0.56% was achieved with the introduction of perovskite layer. The PCE was approximately six times greater than the device without perovskite layer, as a result of wider light absorption range and higher exciton dissociation efficiency.
Effect of Sintering Temperature on Properties of Multiferroic BaFe12O19/MgFe2O4/BaTiO3 Composites
Authors: Zolkepli M.F.A. , Awang Rozidawati , Zainuddin Zalita
Published: March 2016

In this paper, the structural, magnetic and electrical properties of multiferroic BaFe12O19/MgFe2O4/BaTiO3 composites have been studied. BaFe12O19/MgFe2O4/BaTiO3 composites were synthesized by using the conventional solid state reaction technique and sintered at different temperatures. XRD analysis confirmed the existence of hexagonal BaFe12O19, cubic spinel MgFe2O4 and tetragonal BaTiO3 for ferrites and ferroelectric phases, respectively. The suitable sintering temperature for preparing BaFe12O19/MgFe2O4/BaTiO3 composites is between 1000 °C and 1050 °C. SEM analysis showed that as a whole the grain size increases and the pores is reduced with sintering temperature; thus the sample became denser. The coercive field and saturation magnetization decreases when sintering temperature is increased. Resistance of the samples decrease from 103 kW to 19 kW while the capacitance increases from 0.8 nF to 4.0 nF with sintering temperature.
Electrochemical Properties of Glyme Based Plasticizer on Gel Polymer Electrolytes Doped with Lithium Bis(Trifluoromethanesulfonyl)Imide
Authors: Razalli S.M.M. , Saaid S.I.Y.S.M. , Kudin Tengku Ishak Tengku , Yahya Muhd Zu Azhan , Hassan Oskar Hasdinor , Marwan Bin Ali Abdul Malik
Published: March 2016

In this study, gel polymer electrolytes (GPEs) system is prepared by the solution cast technique. The system consists of cellulose acetate (CA) as a host polymer, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as a dopant salt and diethylene glycol dibutylether (BDG) from glyme based family as a plasticizer. GPEs (65 wt. % CA–25 wt. % LiTFSI–10 wt. % BDG) sample is the highest conductivity of 2.88×10-3 S.cm−1 at room temperature. The lithium-electrolyte interfaced stability is established and the highest ionic conducting electrolyte is able to withstand up to 3.8V vs Li/Li+.
Reactivity Study of LaSrCoFeO3 - Ba(Ce,Zr)O3 Composite Cathode Material
Authors: Osman Nafisah , Ismail Ismariza , Samat Abdullah Abdul , Md Jani Abdul Mutalib
Published: March 2016

This paper reports on the reactivity study of composite cathode materials that comprises different weight percent of La0.6Sr0.4Co0.2Fe0.8O3-α (LSCF) and BaCe0.54Zr0.36Y0.1O3-α (BCZY). BCZY and LSCF powders are both prepared by a sol-gel method using metal nitrate salts as precursor. In this work, three samples with different weight percent ratios of 30, 50 & 70% of LSCF to BCZY were used and denoted as sample A1, A2 and A3, respectively. The powder mixtures of all samples were calcined at temperature of 1000 °C for 10 hours in an air. The phase formation of the samples was identified by X-ray diffractometer (XRD). As a comparison, XRD measurements for the LSCF and BCZY powders were also conducted individually, and their single-phase XRD pattern was used to identify the formation of undesired secondary reaction of the powdered mixture. The analysis of room temperature XRD data revealed that A1, A2 and A3 samples exhibit a complete solid solution between the crystal structures of LSCF cathode and BCZY electrolyte. The peaks can be indexed to (110), (020), (202), (220), (132), (224), (332) that belong to the LCSF phase and (110), (200), (211), (220), (310), (222) peaks that fit to the BCZY phase. No additional reaction products or secondary phases were observed indicating that up to 1000 °C, the prepared mixture formed a decent LSCF-BCZY composite. The average values of the lattice parameters for all the samples confirmed their phases were stable with the increasing BCZY content. Thus, it found that the LSCF is compatible with BCZY to form LSCF-BCZY composite for potential cathode material.
Density Functional Study of Electronic and Optical Properties of Ternary Mixed Chalcogenides Topological Insulators
Authors: Shuaibu Alhassan , Rahman Md Mahmudur , Zainuddin Hishamuddin , Talib Zainal Abdib
Published: March 2016

This paper presented a theoretical study of structural, electronic, and optical properties of the ternary mixed chalcogenides Topological Insulators with a formula M2X2Y (M = Bi, X = Te and Y= Se, S) using density functional theory (DFT) within the local density approximation (LDA). From the calculation, we have evaluated the bulk modulus and its corresponding pressure derivatives of these compounds. The linear photon-energy dependent of dielectric functions, some optical properties such as reflectivity, refraction index, conductivity function, and energy-loss spectra, have also been obtained and analyzed within the electronic band structures and density of states of these compounds.
Effect of Samarium Nanoparticles on Optical Properties of Zinc Borotellurite Glass System
Authors: Hajer Saad S. , Halimah M.K. , Zakaria Azmi , Azlan M.N.
Published: March 2016

The glass series of samarium nanoparticles (NPs) doped zinc borotellurite glasses were successfully fabricated by using conventional melt-quenching technique. The structural properties of the prepared glasses were investigated by X-ray diffraction (XRD) analysis and FTIR analysis. It was confirmed that the prepared glasses are amorphous in nature. The bonding parameters of the glasses were analyzed by using FTIR analysis and were found the formation of non-bridging oxygen. The density of these glasses were measured and found to be increased with increasing samarium NPs content. The optical absorption spectra of these glasses were revealed that the fundamental absorption edge shifts to higher wavelengths as the content of Sm2O3 (NPs) increases. The optical energy band gap are found to be decreased linearly with an increasing samarium NPs concentration which is due to the formation of non-bridging oxygen in the glass system.KeywordsBorotellurite glass; optical band gap, Samarium nanoparticles.
Lattice Strain Effect in Structural, Magnetoresistance and Electrical Properties of La0.67Sr0.33MnO3 Bulk and Thin Film System
Authors: Pah Lim Kean , Albert Gan Han Ming , Chen Soo Kien , Talib Zainal Abdib , Halim S.A. , Ng Siau Wei , Chin Hui Wei
Published: March 2016

Polycrystalline La0.67Sr0.33MnO3 (LSMO) powder prepared via conventional solid state reaction was pressed into pellet form. The pellets became target to growth thin films on corning glass (LSMO-C), fused silica (LSMO-FS) and MgO (100) (LSMO-M) substrate via pulsed laser deposition (PLD) method. XRD results showed that all samples were hexagonal structure with R-3C space group. Thin films showed relatively smaller crystallite size compared to bulk samples. From Rietveld Refinement analysis, all thin films experienced lattice strain when deposited on different substrate. LSMO compound deposited in different substrate induced structure distortion and lattice strain. Compression along c-axis occurred when the lattice strain increased thus shifted the metal-insulator transition temperature to lower temperature and increased its resistivity.
Fabrication and Characterization of PANI-Ag-Co Nanocomposite Thin Films as Microbial Sensor for E. coli Detection
Authors: Naim Norshafadzila Mohammad , Abdullah Huda , Azmy Noor Azwen Noor , Umar Akrajas Ali , Hamid Aidil Abdul , Shaari Sahbudin
Published: March 2016

Conducting polymers are excellent host materials for nanoparticles of metals and semiconductors. PANI-Ag-Co nanocomposite was prepared by chemical oxidative polymerization of aniline monomer in the presence of nitric acid. PANI-Ag-Co thin films were deposited on the glass substrate using spin-coating technique. The films were characterized by UV-Vis spectroscopy, XRD, AFM and TEM to analyze the internal structure and surface morphology. The performance of the sensor was conducted using I–V measurement to obtain the changes in the current before and after the incubation with E. coli bacteria in water. In UV-visible absorbance bands, a single peak appears at 421.6 nm in each band indicating the Ag-Co alloy nanoparticles were formed. The peaks in the XRD patterns show the crystals are oriented along (111) planes for Ag while (200) plane for Co. AFM images indicate the surface roughness of the PANI-Ag-Co films decreases when the concentration of Co increased. TEM image shows spherical shaped of Ag-Co alloy particles with diameter in the range of 6 – 10 nm. I–V measurements show that the current change of the films increased when incubated in E. coli. The sensitivity on E. coli increases as we increase the Co concentration. PANI-Ag-Co nanocomposite thin films can be explored further for microbial sensor application in future study.
First-Principles Study on Structural, Electronic and Optical Properties of TiO2 for Dye-Sensitized Solar Cells Photoanode
Authors: Samat Mohd Hazrie , Hussin N.H. , Taib Mohamad Fariz Mohamad , Yaakob Muhamad Kamil , Samsi Noor Syafiqah , Aziz Siti Sumaiyah Sheikh Abdul , Yahya M.Z.A. , Ali A.M.M.
Published: March 2016

First-principles study based on density functional theory (DFT) framework for structural, electronic and optical properties of titanium dioxide (TiO2) in anatase and rutile phases are investigated. Anatase phase exhibits wide band gap compare to rutile phase. The partial and total density of states for TiO2 (anatase and rutile) describes the occupying of titanium (Ti) and oxygen (O) atoms at each energy level. TiO2 has a high dielectric constant to avoid the recombination process while its high refractive index provides the efficient of light diffusion. The optical absorption of TiO2 occurs in ultraviolet (UV) light of the wavelength photon. The results from the first-principles calculations will be helpful to give an understanding about the properties of TiO2 as promising photoanode in dye-sensitized solar cell (DSSC).
Structural, Electronic and Optical Properties of Nd-Doped Anatase TiO2 for Dye-Sensitized Solar Cells from Density Functional Theory
Authors: Samat Mohd Hazrie , Hussin N.H. , Taib Mohamad Fariz Mohamad , Yaakob Muhamad Kamil , Samsi Noor Syafiqah , Aziz Siti Sumaiyah Sheikh Abdul , Yahya M.Z.A. , Ali A.M.M.
Published: March 2016

The structural, electronic and optical properties of pure and neodymium (Nd) doped anatase titanium dioxide (TiO2)are investigated via first-principles calculations within density functional theory (DFT) approach. The band gap reduces to ~0.398 eV when Ti4+ is substituted with Nd3+ in TiO2 crystal structure. The presence of Nd 4f states in the conduction band of TiO2 clarifies the reducing of the band gap. The dielectric constant and refractive index of Nd-doped TiO2 increase compare to pure TiO2. Nd-doped TiO2 able to enhance light absorption to longer wavelength spectrum. The first-principles results obtained satisfy the criteria for Nd-doped TiO2 to become feasible photoanode material in dye-sensitized solar cell (DSSC) device.
Бирациональные координаты Дарбу на (ко)присоединенных орбитах группы $\operatorname{GL}(N,\mathbb C)$
Authors: Babich Mikhail Vasil'evich
Published: March 2016

Множество линейных преобразований, имеющих фиксированную жорданову структуру $J$, является симплектическим многообразием, изоморфным коприсоединенной орбите $\mathcal{O}(J)$ общей линейной группы $\operatorname{GL}(N,\mathbb C)$. Линейное преобразование может быть спроектировано вдоль собственного подпространства на координатное подпространство дополнительной размерности. Жорданова структура проекции $\tilde J$ определяется структурой прообраза $J$; следовательно, проекция $\mathcal{O} (J)\to \mathcal{O} (\tilde J)$ является отображением симплектических многообразий.
В статье доказано, что слой $\mathscr{E}$ этой проекции является линейным симплектическим пространством, а отображение $\mathcal{O}(J)\stackrel{\sim}{\to} \mathscr{E} \times \mathcal{O} (\tilde J)$ - это бирациональный симплектоморфизм. Последовательное проектирование получаемых преобразований вдоль собственных подпространств дает изоморфизм между $\mathcal{O} (J)$ и линейным симплектическим пространством, являющимся декартовым произведением слоев проекций.
Координаты Дарбу на $\mathcal{O}(J)$ являются поднятием канонических координат с этого линейного симплектического пространства.
В качестве примеров построены канонические координаты на орбитах, соответствующих различным жордановым структурам.
Об усреднении несамосопряженных периодических эллиптических операторов в бесконечном цилиндре
Authors: Senik Nikita N
Published: March 2016

Мы рассматриваем оператор $\mathcal{A}^{\varepsilon}$ в $L_{2}(\mathbb{R}^{d_{1}}\times\mathbb{T}^{d_{2}})$ ($d_{1}$ положительно, а $d_{2}$ может быть равно нулю) вида
$\mathcal{A}^{\varepsilon}=-\operatorname{div} A(\varepsilon^{-1}x_{1},x_{2})\nabla$, где $A$ есть функция, периодическая по первой переменной и гладкая в некотором смысле - по второй. Мы находим приближения по операторной норме для резольвент $(\mathcal{A}^{\varepsilon}-\mu)^{-1}$
и $\nabla(\mathcal{A}^{\varepsilon}-\mu)^{-1}$ (с подходящим $\mu$), когда параметр $\varepsilon$ мал. Также мы приводим точные по порядку оценки погрешностей этих приближений.
Омега-предельные множества типичных точек частично гиперболических диффеоморфизмов
Authors: Minkov Stanislav Sergeyevich , Okunev Aleksey Vladimirovich
Published: March 2016

Мы докажем, что $\omega$-предельное множество метрически типичной точки состоит из неустойчивых слоев для любого $E^u \oplus E^{cs}$-частично гиперболического $C^2$-диффеоморфизма. Из этого следует справедливость гипотезы из работы Ю. С. Ильяшенко 2011 г., которая утверждает, что аттрактор Милнора состоит из неустойчивых слоев. В упомянутой работе к этой гипотезе была сведена локальная типичность существования «толстого» аттрактора Милнора в классе диффеоморфизмов произведения отрезка на двумерный тор, сохраняющих край.
Global dimming and urbanization: did stronger negative SSR trends collocate with regions of population growth?
Authors: Imamovic Adel , Tanaka Katsumasa , Folini Doris , Wild Martin
Published: March 2016

Abstract. Global dimming refers to the decrease in surface solar radiation (SSR) observed from the 1960s to the 1980s at different measurement sites all around the world. It is under debate whether anthropogenic aerosols emitted from urban areas close to the measurement sites are mainly responsible for the dimming. In order to assess this urbanization impact on SSR, we use spatially explicit population density data of 0.08° resolution to construct population indices (PI) at 157 high data quality sites. Our study extends previous population-based studies by incorporating distance-weighting as a simple aerosol diffusion model. We measured urbanization in the surrounding of a site as the PI change from 1960 to 1990 and found no negative correlation with the corresponding SSR trends from 1964 to 1989 for the 92 sites in Europe and Japan. For the 39 sites in China the correlation coefficients are significant at the 5 % level and reach around −0.35, while for the 26 remaining Asian, mostly Russian sites the correlation coefficients reach around −0.55 at the 1 % significance level. Results are similar, when the absolute levels of PIs are taken as an indicator for urbanization. Our findings call into question the existence of an urbanization effect for the sites in Europe and Japan, while such an effect cannot be ruled out for the sites in Asia, especially in Russia.
Detailed budget analysis of HONO in central London reveals a missing daytime source
Authors: Lee J. D. , Whalley L. K. , Heard D. E. , Stone D. , Dunmore R. E. , Hamilton J. F. , Young D. E. , Allan J. D. , Laufs S. , Kleffmann J.
Published: March 2016

Abstract. Measurements of HONO were carried out at an urban background site near central London as part of the Clean air for London (ClearfLo) project in summer 2012. Data were collected from 22 July to 18 August 2014, with peak values of up to 1.8 ppbV at night and non-zero values of between 0.2 and 0.6 ppbV seen during the day. A wide range of other gas phase, aerosol, radiation, and meteorological measurements were made concurrently at the same site, allowing a detailed analysis of the chemistry to be carried out. The peak HONO/NOx ratio of 0.04 is seen at  ∼  02:00 UTC, with the presence of a second, daytime, peak in HONO/NOx of similar magnitude to the night-time peak, suggesting a significant secondary daytime HONO source. A photostationary state calculation of HONO involving formation from the reaction of OH and NO and loss from photolysis, reaction with OH, and dry deposition shows a significant underestimation during the day, with calculated values being close to 0, compared to the measurement average of 0.4 ppbV at midday. The addition of further HONO sources from the literature, including dark conversion of NO2 on surfaces, direct emission, photolysis of ortho-substituted nitrophenols, the postulated formation from the reaction of HO2 ×  H2O with NO2, photolysis of adsorbed HNO3 on ground and aerosols, and HONO produced by photosensitized conversion of NO2 on the surface increases the daytime modelled HONO to 0.1 ppbV, still leaving a significant missing daytime source. The missing HONO is plotted against a series of parameters including NO2 and OH reactivity (used as a proxy for organic material), with little correlation seen. Much better correlation is observed with the product of these species with j(NO2), in particular NO2 and the product of NO2 with OH reactivity. This suggests the missing HONO source is in some way related to NO2 and also requires sunlight. Increasing the photosensitized surface conversion rate of NO2 by a factor of 10 to a mean daytime first-order loss of  ∼ 6 × 10−5 s−1 (but which varies as a function of j(NO2)) closes the daytime HONO budget at all times (apart from the late afternoon), suggesting that urban surfaces may enhance this photosensitized source. The effect of the missing HONO to OH radical production is also investigated and it is shown that the model needs to be constrained to measured HONO in order to accurately reproduce the OH radical measurements.
Temporal consistency of lidar observations during aerosol transport events in the framework of the ChArMEx/ADRIMED campaign at Minorca in June 2013
Authors: Chazette Patrick , Totems Julien , Ancellet Gérard , Pelon Jacques , Sicard Michaël
Published: March 2016

Abstract. We performed synergetic daytime and nighttime active and passive remote-sensing observations at Minorca (Balearic Islands, Spain), over more than 3 weeks during the Chemistry-Aerosol Mediterranean Experiment/Aerosol Direct Radiative Effect in the Mediterranean (ChArMEx/ADRIMED) special observation period (SOP 1a, June–July 2013). We characterized the aerosol optical properties and type in the low and middle troposphere using an automated procedure combining Rayleigh–Mie–Raman lidar (355, 387 and 407 nm) with depolarization (355 nm) and AERONET Cimel® sun-photometer data. Results show a high variability due to varying dynamical forcing. The mean column-averaged lidar backscatter-to-extinction ratio (BER) was close to 0.024 sr−1 (lidar ratio of  ∼ 41.7 sr), with a large dispersion of ±33 % over the whole observation period due to changing atmospheric transport regimes and aerosol sources. The ground-based remote-sensing measurements, coupled with satellite observations, allowed the documentation of (i) dust particles up to 5 km (above sea level) in altitude originating from Morocco and Algeria from 15 to 18 June with a peak in aerosol optical thickness (AOT) of 0.25 ± 0.05 at 355 nm, (ii) a long-range transport of biomass burning aerosol (AOT  =  0.18 ± 0.16) related to North American forest fires detected from 26 to 28 June 2013 by the lidar between 2 and 7 km and (iii) mixture of local sources including marine aerosol particles and pollution from Spain. During the biomass burning event, the high value of the particle depolarization ratio (8–14 %) may imply the presence of dust-like particles mixed with the biomass burning aerosols in the mid-troposphere. For the field campaign period, we also show linearity with SEVIRI retrievals of the aerosol optical thickness despite 35 % relative bias, which is discussed as a function of aerosol type.
Hydroxyl Radical in/on Illuminated Polar Snow: Formation Rates, Lifetimes, and Steady-State Concentrations
Authors: Chen Zeyuan , Chu Liang , Galbavy Edward S. , Ram Keren , Anastasio Cort
Published: March 2016

Abstract. While hydroxyl radical (·OH) in the snowpack is likely a dominant oxidant for organic species and bromide, little is known about the kinetics or steady-state concentrations of ·OH on/in snow and ice. Here we measure the formation rate, lifetime, and concentration of ·OH for illuminated polar snow samples studied in the laboratory and in the field. Laboratory studies show that ·OH kinetics and steady-state concentrations are essentially the same for a given sample studied as ice and liquid, in contrast to other oxidants, which show a concentration enhancement in ice relative to solution. The average production rate of ·OH in samples studied at Summit, Greenland is 5 times lower than the average measured in the laboratory, while the average ·OH lifetime determined in the field is 5 times higher than in the laboratory. These differences indicate the polar snows studied in the laboratory are affected by contamination, despite efforts to prevent this. Steady-state concentrations of ·OH in snow studied in the field at Summit, Greenland range from (0.8 to 3) × 10−15 M, comparable to values reported for mid-latitude cloud and fog drops, rain, and deliquesced marine particles, even though impurity concentrations in the snow samples are much lower. Partitioning of firn-air ·OH to the snow grains will approximately double the steady-state concentration of snow-grain hydroxyl radical, leading to an average [·OH] in near-surface, summer Summit snow of approximately 4 × 10−15 M. At this concentration, the ·OH-mediated lifetimes of organics and bromide in Summit snow grains are approximately 3 days and 7 hours, respectively, suggesting that hydroxyl radical is a major oxidant for both species.
Assessment of errors and biases in retrievals of XCO2, XCH4, XCO, and XN2O from a 0.5 cm−1 resolution solar viewing spectrometer
Authors: Hedelius Jacob K. , Viatte Camille , Wunch Debra , Roehl Coleen , Toon Geoffrey C. , Chen Jia , Jones Taylor , Wofsy Steven C. , Franklin Jonathan E. , Parker Harrison , Dubey Manvendra K. , Wennberg Paul O.
Published: March 2016

Abstract. Bruker™ EM27/SUN instruments are mobile commercial solar-viewing near-IR spectrometers. They show promise for expanding the global density of atmospheric column measurements of greenhouse gases and are being marketed for such applications. They have been shown to measure the same variations of atmospheric gases within a day as the high resolution spectrometers of the Total Carbon Column Observing Network (TCCON). However, there is little known about the long-term stability and uncertainty budgets of EM27/SUN measurements. In this study, which includes a comparison of 186 measurement days spanning 11 months, we note that atmospheric variations of Xgas within a single day are well captured by these low-resolution instruments, but over several months, the measurements drift noticeably. We present comparisons between EM27/SUN instruments and the TCCON using GFIT as the retrieval algorithm. In addition, we perform several tests to evaluate the robustness of the performance and determine the largest sources of errors from these spectrometers. We include comparisons of XCO2 and XCH4, and for the first time present comparisons of XCO and XN2O. Specifically we note EM27/SUN biases of 0.03 %, 0.75 %, −0.12 %, and 2.43 % for XCO2, XCH4, XCO, and XN2O respectively with 1σ precisions of 0.08 % and 0.06 % for XCO2 and XCH4 from measurements in Pasadena. We also identify significant error caused by non-linear sensitivity when using an extended spectral range detector used to measure CO and N2O.
Empirical Bayes approach to climate model calibration
Authors: Jackson Charles S. , Huerta Gabriel
Published: March 2016

Abstract. Climate data is highly correlated through the physics and dynamics of the atmosphere. Model evaluation often involves averages of various quantities over different regions and seasons making it difficult from a statistical perspective to quantify the significance of differences that arise between a model and observations. Here we present a strategy that makes use of a set of perfect modeling experiments to quantify the effects of these correlations on model evaluation metrics. This information is incorporated into Bayesian inference through a precision parameter with informative priors. These concepts are illustrated through an example of fitting a line through data that includes either uncorrelated or correlated noise as well as to the calibration of CAM3.1. The concept of a precision parameter may be applied as a strategy to weight different climate model evaluation metrics within a multivariate normal framework. From the example with CAM3.1, the precision parameter plays a central role in rescaling the estimated parametric uncertainties to better accommodate modeling structural errors.
Couplerlib: a metadata-driven library for the integration of multiple models of higher and lower trophic level marine systems with inexact functional group matching
Authors: Beecham Jonathan , Bruggeman Jorn , Aldridge John , Mackinson Steven
Published: March 2016

Abstract. End-to-end modelling is a rapidly developing strategy for modelling in marine systems science and management. However, problems remain in the area of data matching and sub-model compatibility. A mechanism and novel interfacing system (Couplerlib) is presented whereby a physical–biogeochemical model (General Ocean Turbulence Model–European Regional Seas Ecosystem Model, GOTM–ERSEM) that predicts dynamics of the lower trophic level (LTL) organisms in marine ecosystems is coupled to a dynamic ecosystem model (Ecosim), which predicts food-web interactions among higher trophic level (HTL) organisms. Coupling is achieved by means of a bespoke interface, which handles the system incompatibilities between the models and a more generic Couplerlib library, which uses metadata descriptions in extensible mark-up language (XML) to marshal data between groups, paying attention to functional group mappings and compatibility of units between models. In addition, within Couplerlib, models can be coupled across networks by means of socket mechanisms. As a demonstration of this approach, a food-web model (Ecopath with Ecosim, EwE) and a physical–biogeochemical model (GOTM–ERSEM) representing the North Sea ecosystem were joined with Couplerlib. The output from GOTM–ERSEM varies between years, depending on oceanographic and meteorological conditions. Although inter-annual variability was clearly present, there was always the tendency for an annual cycle consisting of a peak of diatoms in spring, followed by (less nutritious) flagellates and dinoflagellates through the summer, resulting in an early summer peak in the mesozooplankton biomass. Pelagic productivity, predicted by the LTL model, was highly seasonal with little winter food for the higher trophic levels. The Ecosim model was originally based on the assumption of constant annual inputs of energy and, consequently, when coupled, pelagic species suffered population losses over the winter months. By contrast, benthic populations were more stable (although the benthic linkage modelled was purely at the detritus level, so this stability reflects the stability of the Ecosim model). The coupled model was used to examine long-term effects of environmental change, and showed the system to be nutrient limited and relatively unaffected by forecast climate change, especially in the benthos. The stability of an Ecosim formulation for large higher tropic level food webs is discussed and it is concluded that this kind of coupled model formulation is better for examining the effects of long-term environmental change than short-term perturbations.
An investigation of the thermo-mechanical features of Laohugou Glacier No. 12 in Mt. Qilian Shan, western China, using a two-dimensional first-order flow-band ice flow model
Authors: Wang Yuzhe , Zhang Tong , Ren Jiawen , Qin Xiang , Liu Yushuo , Sun Weijun , Chen Jizu , Ding Minghu , Du Wentao. , Qin Dahe
Published: March 2016

Abstract. En-glacial thermal conditions are very important for controlling ice rheology. By combining in situ measurements and a two-dimensional thermo-mechanically coupled ice flow model, we investigate the present thermal status of the largest valley glacier (Laohugou No. 12; LHG12) in Mt. Qilian Shan in the arid region of western China. Our model results suggest that LHG12, previously considered as fully cold, is probably polythermal, with a lower temperate ice layer (approximately 5.4 km long) overlain by an upper layer of cold ice over a large region of the ablation area. Generally, modelled ice surface velocities match in situ observations in the east branch (mainstream) well but clearly underestimate the ice surface velocities near the glacier terminus because the convergent flow of the west branch is ignored. The modelled ice temperatures agree closely with the in situ measurements (with biases less than 0.5 K) from a deep borehole (110 m) in the upper ablation area. The model results were highly sensitive to surface thermal boundary conditions, for example, surface air temperature and near-surface ice temperature. In this study, we suggest using a combination of surface air temperatures and near-surface ice temperatures (following the work of Wohlleben et al., 2009) as Dirichlet surface thermal conditions to include the contributions of the latent heat released during refreezing of surface melt-water in the accumulation zone. Like many other alpine glaciers, strain heating is the most important parameter controlling the en-glacial thermal structure in LHG12.
Afgeschermd wonen in Nederland: een studie naar waarom mensen hiervoor kiezen en hoe zij omgaan met interne regelgeving
Authors: Schuilenburg Marc , Van Steden Ronald
Published: March 2016

Protected living in the Netherlands: why do people choose this way of living and how do they handle internal rules?

Protected living in some sort of gated community is popular. However Dutch protected living differs from, for instance, the living in American gated communities, the development tends to social discussions whether it is undesirable or not. Safety seems in the Netherlands not the first reason for protected living. Here, domestic and aesthetic reasons are much more important.
Spot on! Zelfredzaamheid en verwachtingen van burgers bij een black-out
Authors: De Pauw Evelien , Dormaels Arne , Easton Marleen
Published: March 2016

Spot on! Self-efficacy and expectations of citizens during a black-out

Since winter 2014, Belgian is faced with a possible rolling out of power. Blackouts come without any warning whilst the duration and cause of it is mostly unclear. Rolling outs are usually planned by utility companies to put small service areas without electricity, to cope with a high energy demand that the utility companies can’t supply. This rolling out plan can prevent a larger blackout and should make people aware of the consequences of a possible black-out.

Given this situation, this paper presents the result of a study asking citizens about their self-efficacy and organizations of their own house hold to deal with possible blackouts. For this survey, 473 citizens have been interviewed in 2 Belgian cities. We asked about their own action to organize themselves and were looking at their expectations of the government.
A importância da supervisão colaborativa no desenvolvimento profissional do docente de educação especial
Authors: Gomes Ana Maria Paula Marques , Vieira Maria da Conceição Martins
Published: March 2016

As atuais tendências supervisivas apontam para a supervisão entre pares, uma conceção democrática de supervisão que valoriza a reflexão e a aprendizagem em colaboração, levando os professores a gerar e a partilhar atividades e conhecimentos. Acreditamos que o trabalho dos docentes em equipa, centrado na reflexão, poderá promover um desenvolvimento profissional adequado às necessidades individuais e às exigências de uma profissão em que o professor se vê permanentemente confrontado com novas situações e desafios. As práticas colaborativas assentes na troca e partilha de experiências proporcionam aprendizagens diretas, aumentam a quantidade e a qualidade de soluções e ideias e a qualidade das opções realizadas. Assim, no desenvolvimento desta investigação, de natureza descritiva/interpretativa e numa abordagem predominantemente qualitativa, definimos objetivos distintos e complementares determinados pelo refletir sobre modelos e práticas supervisivas, verificar práticas colaborativas em contexto de sala de educação especial, potenciar a utilização das Tecnologias de Informação e Comunicação (TIC) no trabalho colaborativo e identificar fatores de constrangimento e de facilitação da prática de supervisão colaborativa na sala de educação especial. Dos resultados obtidos no estudo parece-nos fundamental ressaltar que na prática supervisiva deverá existir um diálogo aberto e verdadeiro interpares competindo ao supervisor, enquanto membro do corpo docente com funções supervisivas, transmitir a ideia de que todo o processo supervisivo interpares não é a avaliação, mas sim um melhor conhecimento do ato educativo, facultando a tomada de decisões pedagógicas mais adequadas.
Alegorias do contemporâneo: articulações e efeitos entre identidades culturais e consumo
Authors: Lazzarin Luís Fernando
Published: March 2016

Este trabalho investiga como vêm sendo produzidas, na publicidade, diferentes articulações entre identidades culturais e consumo. São apresentadas análises de dois vídeos publicitários da Natura Cosméticos S.A. e outros dois da Coca Cola Company. Os vídeos referidos são concebidos como pedagogias culturais não-escolares, pois, embora não possuam um currículo no sentido escolar de planejamento e de organização daquilo que deve ser ensinado, produzem diferentes modos de ser e de pertencimento. A análise levanta diferentes alegorias colocadas em circulação nos vídeos: a naturalização das identidades culturais e sua utilização como recurso; a relação cada vez mais íntima entre consumo e cidadania; o pertencimento e a solidariedade por meio do consumo, que prescinde de fronteiras geográficas. Captar e descrever esses elementos e seus sentidos parece ser extremamente importante para a formação dos futuros professores. Isso implica aprender a negociar com os apelos e as imposições do consumo e permite oferecer resistência (ou seja, cria possibilidades de escolha) em meio ao que parece ser uma força avassaladora da contemporaneidade.
Doing the Math: Supporting Student Justifications
Authors: James Carolyn , Philiben Lyn , Knievel Molly
Published: March 2016

When teachers consider the many sides of a task, they are better prepared to help students through future mathematically sticky problems.
What is your body mass index?
Authors: Yanik H. Bahadir , Memis Yasin
Published: March 2016

The number of people who are obese or overweight has dramatically increased throughout the world in recent years. This article presents an activity in which fifth- and sixth-grade students analyzed body mass index (BMI) and planned a diet accordingly; an interactive simulation supported the creation of a healthy eating regimen. iSTEM (Integrating Science, Technology, and Engineering in Mathematics) authors share ideas and activities that stimulate student interest in the integrated fields of science, technology, engineering, and mathematics (STEM) in K–grade 6 classrooms.
Representaciones de un territorio. La frontera mapuche en los proyectos ilustrados del Reino de Chile en la segunda mitad del siglo XVIII
Authors: Gándara Natalia
Published: March 2016

The objective of this article is to analyze the representations elaborated by the authorities of the Kingdom of Chile regarding the territory of the Mapuche frontier. The research was done on the basis of four projects of territorial expansion promoted during the second half of the 18th century. The findings of this study indicate that those who planned these projects devised peaceful strategies for integrating said frontier into the Kingdom of Chile, in order to articulate said space in defensive-strategic terms and incorporate it into the colonial culture and economy. The projects were designed by intellectuals who adapted the principles of the Enlightenment to resolve the problem of the frontier, thus creating new representations regarding this space that emphasized its importance within the Spanish colonial territorial system.
Ilustración y educación. La Congregación del Oratorio de San Felipe Neri en Nueva España (siglo XVIII)
Authors: Castañeda García Rafael
Published: March 2016

The present article seeks to show the participation of the Congregation of the Oratory of St. Philip Neri in the process of spreading literacy in New Spain during the 18th century. Through an analysis of a variety of handwritten and edited documentary sources, it shows that the order founded by St. Philip Neri contributed to the enlightened project through its work of promoting public education for both sexes and the inclusion of modern disciplines in the education offerings of its secondary and primary schools, especially in the Bajío region.
The structure and dynamics of secretory component and its interactions with polymeric immunoglobulins
Authors: Stadtmueller Beth M , Huey-Tubman Kathryn E , López Carlos J , Yang Zhongyu , Hubbell Wayne L , Bjorkman Pamela J
Published: March 2016

As a first-line vertebrate immune defense, the polymeric immunoglobulin receptor (pIgR) transports polymeric IgA and IgM across epithelia to mucosal secretions, where the cleaved ectodomain (secretory component; SC) becomes a component of secretory antibodies, or when unliganded, binds and excludes bacteria. Here we report the 2.6Å crystal structure of unliganded human SC (hSC) and comparisons with a 1.7Å structure of teleost fish SC (tSC), an early pIgR ancestor. The hSC structure comprises five immunoglobulin-like domains (D1-D5) arranged as a triangle, with an interface between ligand-binding domains D1 and D5. Electron paramagnetic resonance measurements confirmed the D1-D5 interface in solution and revealed that it breaks upon ligand binding. Together with binding studies of mutant and chimeric SCs, which revealed domain contributions to secretory antibody formation, these results provide detailed models for SC structure, address pIgR evolution, and demonstrate that SC uses multiple conformations to protect mammals from pathogens.
Charge-collection efficiency and long-term stability of single-crystal CVD diamond detector under different carrier-drift conditions
Authors: Sato Yuki , Murakami Hiroyuki , Shimaoka Takehiro , Tsubota Masakatsu , Kaneko Junichi H.
Published: March 2016

We investigate the performance of a charged-particle detector fabricated using single-crystal diamond grown by chemical vapor deposition. The detector identified four different 241Am α-particle energies (5.389, 5.443, 5.486, and 5.545 MeV) thanks to its superior energy resolution of 0.407 ± 0.004% for electron drift and 0.418 ± 0.004% for hole drift (full width at half maximum). The charge-collection efficiency inside the diamond crystal was above 97.0% for both electrons and holes. The diamond detector also exhibited no significant degradation in terms of pulse-height spectra and energy resolution during operation for more than 100 h under electron-drift conditions. In contrast, the pulse-height spectra obtained under hole-drift conditions deteriorated because of the polarization phenomenon.
A 15 × 15 single photon avalanche diode sensor featuring breakdown pixels extraction architecture for efficient data readout
Authors: Yang Xiao , Zhu Hongbo , Nakura Toru , Iizuka Tetsuya , Asada Kunihiro
Published: March 2016

This paper proposes a breakdown pixels extraction architecture for single photon avalanche diode (SPAD) based faint light detection systems. The proposed extraction circuit detects the breakdown pixels and only their addresses are readout. Therefore, under the faint light environment, this SPAD-based sensor significantly improves the data readout efficiency. In addition, since the readout sequence is 4× faster than that of the conventional architecture in the dark condition, the proposed system does not need an independent on-chip event detection circuit that consumes additional area and power. A test-of-concept chip with a 15 × 15 SPAD pixels array was fabricated in a 0.18 µm 1P5M standard CMOS process and pinhole diffraction patterns were successfully captured thanks to the high sensitivity of the SPAD sensor. Under the faint light condition, a high-speed readout is verified by measurement and the robustness of the proposed architecture is successfully demonstrated.
A study of surface semi-geostrophic turbulence: freely decaying dynamics
Authors: Ragone Francesco , Badin Gualtiero
Published: March 2016

In this study we give a characterization of semi-geostrophic turbulence by performing freely decaying simulations for the case of constant uniform potential vorticity, a set of equations known as the surface semi-geostrophic approximation. The equations are formulated as conservation laws for potential temperature and potential vorticity, with a nonlinear Monge–Ampère type inversion equation for the streamfunction, expressed in a transformed coordinate system that follows the geostrophic flow. We perform model studies of turbulent surface semi-geostrophic flows in a domain doubly periodic in the horizontal and limited in the vertical by two rigid lids, allowing for variations of potential temperature at one of the boundaries, and we compare the results with those obtained in the corresponding surface quasi-geostrophic case. The results show that, while the surface quasi-geostrophic dynamics is dominated by a symmetric population of cyclones and anticyclones, the surface semi-geostrophic dynamics features a more prominent role of fronts and filaments. The resulting distribution of potential temperature is strongly skewed and peaked at non-zero values at and close to the active boundary, while symmetry is restored in the interior of the domain, where small-scale frontal structures do not penetrate. In surface semi-geostrophic turbulence, energy spectra are less steep than in the surface quasi-geostrophic case, with more energy concentrated at small scales for increasing Rossby number. The energy related to frontal structures, the lateral strain rate and the vertical velocities are largest close to the active boundary. These results show that the semi-geostrophic model could be of interest for studying the lateral mixing of properties in geophysical flows.
Screening high school students in Italy for sudden cardiac death prevention by using a telecardiology device: a retrospective observational study
Authors: De Lazzari Claudio , Genuini Igino , Gatto Maria C. , Cinque Alessandra , Mancone Massimo , D’Ambrosi Alessandra , Silvetti Elisa , Fusto Antonio , Pisanelli Domenico M. , Fedele Francesco
Published: March 2016

Background

In 2010, an Italian project was launched aimed at using a telecardiology device in order to perform early diagnosis of young students at risk of sudden cardiac death.

Methods

Our retrospective observational study was conducted on a population of 13,016 students, aged between 16 and 19 years, in different Italian regions. It consisted of analysis of data recorded during a telecardiology pilot study. The recorded data were electrocardiograms and data concerning lifestyle habits and family history of cardiovascular diseases. In total, 14 alterations in the electrocardiogram signal have been considered in this study. Some of these alterations are as follows: ventricular ectopic beats, atrioventricular block, Brugada-like electrocardiogram pattern, left anterior/posterior fascicular block, left/right ventricular hypertrophy, long/short QT interval, left atrial enlargement, right atrial enlargement, short PQ interval, and ventricular pre-excitation Wolff–Parkinson–White syndrome. On the basis of the collected data, we implemented this retrospective observational study.

Results

The analysed data showed that 13.60% of students had a family history for cardiovascular diseases, 22.43% reported smoking habits, 26.23% reported alcohol consumption, and 7.24% reported abuse of drugs. A total of 24% of students had at least one of the 14 electrocardiogram pathological alterations considered in our study and 32% had electrocardiogram values within the normal range.

Conclusions

This retrospective observational study analysed data registered during our telecardiology activity. This activity permitted to maximise data collection and minimise the costs for collecting such data. This activity of screening is being continued and in the next few years it will allow us to have a greater mass of data.
Ralstonia solanacearum lipopeptide induces chlamydospore development in fungi and facilitates bacterial entry into fungal tissues
Authors: Spraker Joseph E , Sanchez Laura M , Lowe Tiffany M , Dorrestein Pieter C , Keller Nancy P
Published: March 2016

Ralstonia solanacearum is a globally distributed soil-borne plant pathogenic bacterium, which shares a broad ecological range with many plant- and soil-associated fungi. We sought to determine if R. solanacearum chemical communication directs symbiotic development of polymicrobial consortia. R. solanacearum produced a diffusible metabolite that induced conserved morphological differentiation in 34 species of fungi across three diverse taxa (Ascomycetes, Basidiomycetes and Zygomycetes). Fungi exposed to this metabolite formed chlamydospores, survival structures with thickened cell walls. Some chlamydospores internally harbored R. solanacearum, indicating a newly described endofungal lifestyle for this important plant pathogen. Using imaging mass spectrometry and peptidogenomics, we identified an undescribed lipopeptide, ralsolamycin, produced by an R. solanacearum non-ribosomal peptide synthetase-polyketide synthase hybrid. Inactivation of the hybrid non-ribosomal peptide synthetase-polyketide synthase gene, rmyA, abolished ralsolamycin synthesis. R. solanacearum mutants lacking ralsolamycin no longer induced chlamydospore development in fungal coculture and invaded fungal hyphae less well than wild-type. We propose that ralsolamycin contributes to the invasion of fungal hyphae and that the formation of chlamydospores may provide not only a specific niche for bacterial colonization but also enhanced survival for the partnering fungus.