bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Realized Measure and Implied Volatility in Forecasting Volatility
Authors: Han Heejoon , Park Myung D. 
Published: June 2013

ABSTRACTThis paper compares the information content of realized measures constructed from high‐frequency data and implied volatilities from options in the context of forecasting volatility. The comparison is based on within‐sample and out‐of‐sample (over horizons of 1–22 days) forecasts of daily S&P 500 index return volatility. The paper adds to the findings of previous studies, by considering recent developments in the related practice and the literature. It is shown that, for within‐sample fitting, the realized measure is more informative than the implied volatility. In contrast, the implied volatility is more informative than the realized measure for out‐of‐sample forecasting, in particular for multi‐step‐ahead forecasting. Moreover, we show that it is helpful to use all the information provided by the realized measure and the implied volatility for the within‐sample fitting. For multi‐step‐ahead forecasting, however, it is better to use only the implied volatility. Copyright © 2013 John Wiley & Sons, Ltd.
Versuche zur einaxialen Druckfestigkeit geklebter Gesteinsproben
Authors: Becker Andreas , Vrettos Christos 
Published: June 2013

AbstractDas Kleben von Bauteilen ist eine gängige Sanierungsmaßnahme im konstruktiven Ingenieurbau und im Bergbau, welche weiterentwickelt wird. Verkleben von Gestein stellt eine potentielle Methode der Sicherung von Felsböschungen dar, die jedoch bisher wenig Anwendung erfahren hat. In dem vorliegenden Beitrag wird das Kleben von typischen Gesteinsproben im Labor anhand von einaxialen Druckversuchen untersucht. Neben der Trennflächenneigung wurde die Temperatur beim Abbindevorgang variiert. Die Gegenüberstellung geklebter und intakter Gesteinsproben zeigt die Wirkung der Klebeverbindung.Tests on the uniaxial strength of adhesive‐bonded rock samples. Adhesive bonding of structural parts is a common retrofit measure in structural and mining engineering, which is being further developed. Adhesive bonding of rock is a promising method of slope stabilization that received little attention hitherto. In this paper, the adhesive bonding of typical rock samples is investigated by means of uniaxial compression laboratory tests. Both, the orientation of the discontinuity as well as the temperature during the hardening process are varied in the tests. The comparison of bonded and intact rock samples shows the effect of the adhesive bond.
Prognose von Oberflächensetzungen beim Tunnelvortrieb – Teil II: Möglichkeiten und Grenzen der Finite‐Element‐Berechnung
Authors: Fillibeck Jochen 
Published: June 2013

AbstractDie Prognose von Setzungen bzw. Sackungen oberhalb eines Tunnelvortriebs kann durch die Auswertung von Erfahrungen und Messungen aus vorangegangenen Tunnelbauprojekten – der empirischen Prognose – oder aber durch numerische Berechnungen erfolgen. Im Teil 1 der Veröffentlichung wurde das vom Autor vorgeschlagene empirische Prognoseverfahren vorgestellt, welches auf über 350 sorgfältig ausgewerteten Messquerschnitten basiert und mit dem sich unter vereinfachten Randbedingungen die sich über dem Tunnelvortrieb einstellenden Setzungen leicht berechnen lassen. Im nachfolgenden Teil 2 der Veröffentlichung wird auf numerische Berechnungsmethoden eingegangen, wobei zwischen 2D‐, 3D‐ und 4D‐FE‐Berechnungen unterschieden wird. Anhand von FE‐Berechnungen im Vergleich mit den Ergebnissen oben genannter Messquerschnitte werden Eignung, Möglichkeiten und Grenzen verschiedener Berechnungsverfahren dargestellt. Weiterhin wird durch Gegenüberstellung der Ergebnisse das im Teil 1 beschriebene empirische Prognoseverfahren bewertet, und schließlich werden Vorschläge unterbreitet, wann welches Verfahren vorteilhaft anwendbar ist.Possibilities to predict the surface settlement during tunnelling in soil – Part II: application spectrum and limitations of the finite element calculation. The prediction of settlements over a tunnel excavation can be detected by the evaluation of measurement data available from previous tunnel project sites – the empirical prediction – or by numerical calculations. In part 1 of the publication, the empirical prediction method proposed by the author was introduced, which was derived by more than 350 carefully analyzed measuring sections. By this prediction method and under simplified boundary conditions, the tunnel induced settlement can be estimated easily. The following part 2 of the publication deals with numerical calculation methods. It is distinguished between 2D‐, 3D‐ and 4D‐FE‐Calculations. By comparing FE‐calculations with the results of the above mentioned measuring sections, the application spectrum and limitations of different calculation methods are shown. Further more, by comparison, the proposed empirical prediction method is evaluated. Finally the suitability of both methods according to the existing boundary conditions is discussed.
The nexus between atmospheric rivers and extreme precipitation across Europe
Authors: Lavers David A. , Villarini Gabriele 
Published: June 2013

AbstractExtreme precipitation and floods in Europe are a recurring natural hazard causing large socioeconomic damages. Here we investigate the connection between annual maxima (AM) daily precipitation at a pan‐European scale and atmospheric rivers (ARs), narrow filaments that convey the majority of the poleward water vapor transport within extratropical cyclones. We show that ARs are responsible for many AM precipitation days in Western Europe. The relationship is especially strong along the western European seaboard, with some areas having eight of their top 10 AM related to ARs. The effects of ARs are also seen as far inland as Germany and Poland. Southern Europe was most affected by ARs under negative North Atlantic Oscillation (NAO) conditions, whereas northern Europe was more associated with a positive relationship between ARs and an NAO‐type pattern. Our results suggest that ARs are critical in explaining the upper tail of the extreme precipitation distribution in Western Europe.
Evaluation of an experimental Ti‐Co alloy for dental restorations
Authors: Wang Russell , Welsch Gerhard 
Published: June 2013

AbstractPrecision and surface quality of pure titanium (Ti) castings for dental and biomedical uses are limited because of the high melting temperature and the violent reactivity of Ti with mold materials during casting procedures. This feasibility study evaluates an experimental low‐melting Ti‐Co alloy in term of its microstructure and physical and mechanical properties. Tensile samples of Ti‐12 wt % Co alloy were cast under a protective argon atmosphere. The melting range of the cast samplers was determined. Cast samples were annealed at 1010°C for various time intervals in order to homogenize microstructures. Microstructures were examined by optical and scanning electron microscopy. Tensile strength and microhardness tests were performed and correlated with microstructures resulting from annealing processes. Ti2Co intermetallic compound coexisted with Ti‐Co solid solution in all samples. The melting range of the alloy was 1062–1088°C, which is 568°C lower than that of Ti. The thickness of the surface oxide scale on cast samples was dramatically reduced to 1–3 μm because of the low‐melting nature of the alloy. Solution treatment at 1010°C for 100 h yields the highest tensile strength. Ultimate tensile strength is measured from 852 to 1240 MPa which is stronger than currently used dental alloys. Microhardness values were ranged from 341 to 488 KHN and elongation was from 1.2 to 1.8%. Both microhardness and percentage elongation are similar to those of dental Co‐Cr alloys. One hundred hours of annealing dissolved dendritic boundaries and transformed the alloy to a more microductitle matrix, however, the intermetallic compound of Ti2Co remained. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1419–1427, 2013.
Effect of hydroxyapatite spheres, whiskers, and nanoparticles on mechanical properties of a model BisGMA/TEGDMA composite initially and after storage
Authors: Lezaja Maja , Veljovic Djordje N. , Jokic Bojan M. , Cvijovic‐Alagic Ivana , Zrilic Milorad M. , Miletic Vesna 
Published: June 2013

AbstractThis study investigated the effect of shape, size, and surface modification of hydroxyapatite (HAP) fillers on the degree of conversion (DC) and mechanical properties of a model BisGMA/TEGDMA composite initially and after 4 weeks of storage. Ten percent of conventional glass fillers were replaced by HAP spheres (Sph), silicon‐doped spheres (SphSi), whiskers (Wh), silicon‐doped whiskers (WhSi), and nanosized HAP particles (Nano). Spheres were specifically structured agglomerates consisting of a central void and radially orientated primary particles, whereas whiskers were compact monocrystals. DC, Vickers hardness (HV), flexural strength (Fs), flexural modulus (Ef), compressive strength (Cs), and compressive modulus (Ec) were tested. There were no significant differences in the DC between all tested groups. HV decreased by 5.4–17% with the addition of HAP, while Fs increased by 13.9–29% except in Nano group (decrease by 13%). After storage, Sph and SphSi groups showed similar HV, Ef, Cs and Ec and higher Fs than the control. The fracture mode of HAP spheres was through the central void whereas whiskers showed longitudinal delamination, transverse, and mixed fractures. HAP spheres with or without silicon‐ doping have a potential to be part of the filler content of dental composites. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1469–1476, 2013.
Technology for rerefining used lube oils applied in Europe: a review
Authors: Kupareva Antonina , Mäki‐Arvela Päivi , Murzin Dmitry Yu. 
Published: June 2013

AbstractThe European oil rerefining industry is comprised of 28 plants treating waste oil, which represent one‐third in volume of the total European market for lubricants. The biggest European rerefineries with capacity greater than 40 000 tons/year apply various technologies for recycling of used oils from different sources. Used oil recycling technology has undergone significant changes over the past decade. With the newly developed rerefining technologies it is possible to produce higher quality base oil compared with the traditional and old acid clay methods. Currently in Europe the following re‐refining methods are widely used: solvent extraction (N‐methyl‐2‐pyrrolidone (Germany), Interline process (United Kingdom, Spain)); combined vacuum distillation and solvent extraction (Vaxon process (Denmark, Spain); hydroprocessing (Hylube process (Germany)); combined thin film evaporation and hydrofinishing (CEP process (Finland)); combined thermal de‐asphalting and hydrofinishing (Revivoil process (Italy, Poland, and Spain)). The majority of applied technologies in Europe is appropriate for rerefining of synthetic lubricating oils, which currently are replacing the conventional mineral lube oils due to their enhanced performance characteristics. However, for the rerefining technologies applying alkaline treatment (CEP, Vaxon) and hydrofinishing step (Cyclon, Snamprogetti, Revivoil) the amount of synthetic or semi‐synthetic oils based on esters in the feedstock should be eliminated, since these oils are less stable under alkali and hydrofinishing conditions. © 2013 Society of Chemical Industry
Theoretical and empirical scale dependency of Z‐R relationships: Evidence, impacts, and correction
Authors: Verrier Sébastien , Barthès Laurent , Mallet Cécile 
Published: June 2013

AbstractEstimation of rainfall intensities from radar measurements relies to a large extent on power‐laws relationships between rain rates R and radar reflectivities Z, i.e., Z = a*R^b. These relationships are generally applied unawarely of the scale, which is questionable since the nonlinearity of these relations could lead to undesirable discrepancies when combined with scale aggregation. Since the parameters (a,b) are expectedly related with drop size distribution (DSD) properties, they are often derived at disdrometer scale, not at radar scale, which could lead to errors at the latter. We propose to investigate the statistical behavior of Z‐R relationships across scales both on theoretical and empirical sides. Theoretically, it is shown that claimed multifractal properties of rainfall processes could constrain the parameters (a,b) such that the exponent b would be scale independent but the prefactor a would be growing as a (slow) power law of time or space scale. In the empirical part (which may be read independently of theoretical considerations), high‐resolution disdrometer (Dual‐Beam Spectropluviometer) data of rain rates and reflectivity factors are considered at various integration times comprised in the range 15 s – 64 min. A variety of regression techniques is applied on Z‐R scatterplots at all these time scales, establishing empirical evidence of a behavior coherent with theoretical considerations: a grows as a 0.1 power law of scale while b decreases more slightly. The properties of a are suggested to be closely linked to inhomogeneities in the DSDs since extensions of Z‐R relationships involving (here, strongly nonconstant) normalization parameters of the DSDs seem to be more robust across scales. The scale dependence of simple Z = a*R^b relationships is advocated to be a possible source of overestimation of rainfall intensities or accumulations. Several ways for correcting such scaling biases (which can reach >15–20% in terms of relative error) are suggested. Such corrections could be useful in some practical cases where Z‐R scale biases are significant, which is especially expected for convective rainfall.
Role of meteorological processes in ozone responses to emission controls in California's San Joaquin Valley
Authors: Jin Ling , Loisy Aurore , Brown Nancy J. 
Published: June 2013

AbstractWe conducted a first‐order sensitivity analysis to investigate ozone responses to precursor emissions and source contributions (local versus upwind) for California's San Joaquin Valley (SJV) under four distinct meteorology conditions of summer 2000 using a three‐dimensional photochemical transport model. Ozone‐limiting reagents, nitrogen oxides (NOx), or anthropogenic volatile organic compounds (VOCs) (AVOCs) and their transition regime were determined from ozone sensitivity coefficients and delineated spatially at high‐ozone locations in the SJV. In general, AVOC‐limited areas were located near urban centers, while NOx‐limited areas were located farther downwind. However, the spatial extent of AVOC‐limited areas varied with meteorology. Meteorological dependence of predominant ozone‐limiting precursors was found to vary significantly among different subregions within the SJV. Specifically, weaker dependences were identified for regions of the southern SJV located farther away from emission sources, where ozone chemistry was mostly limited by NOx for the episodes considered. Stronger dependences were identified for the central and northern SJV, where ozone chemistry can be limited by NOx or AVOC depending on meteorology. Source contributions to ozone sensitivities in the SJV were also investigated. Local sources were important for the eastern side of the central SJV, while upwind sources were also important (from ~40% to more than 50% of the total ozone sensitivities) for the western side of the valley, except for the most stagnant episode. Different contributing source regions were identified for the same VOC‐limited areas in the northern SJV, and these depended on the flow characteristics. The predominant ozone‐limiting reagent was found to exhibit less dependence on meteorology in the central and southern SJV as the baseline NOx emissions were reduced, ultimately causing ozone formation to be limited by NOx. In contrast, the VOC‐limited areas in the northern SJV continued to be influenced by meteorology for two of the episodes.
A novel melt stable and high tensile strength biopolymer (polyhydroxyalkanoates) from Bacillus megaterium (MTCC10086) and its characterization
Authors: Bora Limpon , Das Reshmi , Gohain Dibakar 
Published: June 2013

AbstractIn the present investigation, we have defined a novel biopolymer from Bacillus megaterium strain with novel melt stability, high tensile strength, and elongation to break properties higher to polypropylene and similar to polyethylene the polymers available commercially. The polymer was characterized with FTIR and XRD. The percent crystalinity was found to 44.09% with tensile strength 42 (Mpa) and elongation to break (%) 142 higher than polypropylene. The polymeric properties were confirmed by differential scanning calorimeter and universal testing.
Influence of topography on rainfall variability in Santiago Island, Cape Verde
Authors: Sanchez‐Moreno Juan Francisco , Mannaerts Chris M. , Jetten Victor 
Published: June 2013

ABSTRACTCape Verde is a semi‐arid country conformed by a group of islands located off the west coast of Africa, with highly variable rainfall that appears during a single rainy season. Santiago Island, the biggest of the country, is characterized for abrupt changes of relief within small distances. The influence of geographic location and topographic parameters, such as slope gradient, exposition and elevation on the variability of rainfall in Santiago Island was studied using monthly rainfall data of 30 seasons (1981 to 2010), with daily rainfall data for 14 seasons (1997 to 2010). The number of rainfall days and the percentage of maximum daily rainfall within the monthly and seasonal totals were evaluated. Few rainy days can control the monthly and seasonal rainfall patterns of Santiago Island. Multivariate linear regressions among daily, monthly and seasonal rainfall and elevation, slope gradient, aspect, and geographic east and west coordinates as predictors were carried out. Elevation explains most of the variance in the rainfall. The coefficients of determination show an inverse relationship with the rainfall depth: moderate rainfall totals (120–150 mm monthly, 250–300 mm seasonal) produced the best correlations for seasonal and monthly rainfall, while very low (<50 mm for monthly, <200 mm for seasonal) and very high amounts (>250 mm for monthly, >350 mm for seasonal) resulted in poor correlations. Long‐term mean rainfall was interpolated using ordinary kriging and kriging with external drift. In Santiago Island, high and more extreme rainfall events are less influenced by elevation, while low and medium rainfall events are significantly influenced by orography, with most of the rainfall appearing on high elevations. Copyright © 2013 Royal Meteorological Society
Field Performance and Essential Oil Production of Mycorrhizal Rosemary in Restoration Low‐Nutrient Soils
Authors: Camprubi Amelia , Zárate Ingrith Angelica , Adholeya Alok , Lovato Paulo Emilo , Calvet Cinta 
Published: June 2013

AbstractThe establishment and growth of Rosmarinus officinalis L. under field conditions in two low‐nutrient‐content soils were evaluated, as well as the effect of arbuscular mycorrhizal (AM) fungi on essential oil production. The reclamation was conducted in two experimental sites: a limestone quarry and a wasteland soil, both surrounded by Mediterranean vegetation. Mycorrhizal R. officinalis plants inoculated with different AM fungal isolates were used to revegetate the sites. Pre‐transplant inoculation with mycorrhizal fungi resulted in an increased survival of R. officinalis with similar results in both experimental areas. Mycorrhizal inoculation enhanced plant growth, increased essential oil yield and improved the establishment of plants under field conditions. The results indicate that the presence of the symbiosis can accelerate plant growth and alter the biosynthesis of secondary metabolites, thus improving the yield of medicinal plant extracts. It also confirmed the importance of selecting plant/symbiont combinations adapted to the environmental constraints of low‐nutrient‐content soils to design a successful application of mycorrhizal technology in marginal soils. Copyright © 2013 John Wiley & Sons, Ltd.
Lipids in infant formulas: Current and future innovations
Authors: Long Amy C. , Kaiser Jennifer L. , Katz Gary E. 
Published: June 2013

AbstractLipids in infant formulas are designed to mimic the composition of human milk and/or approximate the performance of the breastfed infant. Human milk lipids exhibit a complex, highly variable nature, varying by population, dietary intake, time of day, length of feeding and others. Continued understanding and characterization of human milk lipids has led to infant formula innovations aimed at a better comparison to human milk and/or improved dietary lipid utilization in the formula‐fed infant. The underlying aim of such innovation is the generation of outcomes as comparable to human milk feeding as possible. The present paper briefly reviews the current understanding of human milk lipid composition, with a focus on how this knowledge drives current and future innovations in the area of infant formula lipids.
Low‐level laser therapy for fat layer reduction: A comprehensive review
Authors: Avci Pinar , Nyame Theodore T. , Gupta Gaurav K. , Sadasivam Magesh , Hamblin Michael R. 
Published: June 2013

AbstractBackground and ObjectiveLow‐level laser (light) therapy (LLLT) is a noninvasive, nonthermal approach to disorders requiring reduction of pain and inflammation and stimulation of healing and tissue regeneration. Within the last decade, LLLT started being investigated as an adjuvant to liposuction, for noninvasive body contouring, reduction of cellulite, and improvement of blood lipid profile. LLLT may also aid autologous fat transfer procedures by enhancing the viability of adipocytes. However the underlying mechanism of actions for such effects still seems to be unclear. It is important, therefore, to understand the potential efficacy and proposed mechanism of actions of this new procedure for fat reduction.Materials and MethodsA review of the literature associated with applications of LLLT related to fat layer reduction was performed to evaluate the findings from pre‐clinical and clinical studies with respect to the mechanism of action, efficacy, and safety.ResultsThe studies as of today suggest that LLLT has a potential to be used in fat and cellulite reduction as well as in improvement of blood lipid profile without any significant side effects. One of the main proposed mechanism of actions is based upon production of transient pores in adipocytes, allowing lipids to leak out. Another is through activation of the complement cascade which could cause induction of adipocyte apoptosis and subsequent release of lipids.ConclusionAlthough the present studies have demonstrated safety and efficacy of LLLT in fat layer reduction, studies demonstrating the efficacy of LLLT as a stand‐alone procedure are still inadequate. Moreover, further studies are necessary to identify the mechanism of action. Lasers Surg. Med. 45:349–357, 2013. © 2013 Wiley Periodicals, Inc.
Synthesis of New Poly(ether ketone)s Derived from Biobased Diols
Authors: Abderrazak Hana Ben , Fildier Aurélie , Romdhane Hatem Ben , Chatti Saber , Kricheldorf Hans R. 
Published: June 2013

AbstractA new class of poly(ether ketone)s (PEKs) is prepared by polycondensation of various diols produced from biomass and various difluoro aromatics. After optimization of the reaction conditions, polycondensation of isosorbide and 4,4′‐difluorodiphenylketone (2a) gives PEK1 with a high yield, moderate viscosity (0.31 dL g−1), and a glass‐transition temperature (Tg) of 170 °C. The optimum conditions are applied to the synthesis of a series of PEKs (PEK 2–9) from difluoro agents and sugar diols. The polycondensation of isomannide (1b) with 1,4‐di(p‐fluorobenzoyl)benzene (2b) gives the best results with an inherent viscosity of 0.52 dL g−1 and the mass spectrum shows an abundance of cyclic structures. Similar conditions are used for the preparation of high‐molar‐mass copoly(ether ketone)s from a stoechiometric mixture of isosorbide/bisphenol‐A.magnified image