bluuebunny/crossref_metadata_2025 huggingface dataset:
Rheology‐morphology correlation in PET/PP blends: Influence of type of compatibilizer
Authors: Khonakdar Hossein Ali , Jafari Seyed Hasan , Mirzadeh Salman , Kalaee Mohammad Reza , Zare Davod , Saeb Mohammad Reza
Published: February 2013

Rheological and morphological properties of melt processed poly(ethylene terephthalate) (PET)/polypropylene (PP) blends are presented. Two types of compatibilizer namely, PP‐g‐MA  and Elvaloy PTW, an n‐butyl acrylate glycidyl methacrylate ethylene terpolymers, were incorporated at different levels to the PET/PP blend system. Scanning electron microscopy revealed that the dispersed particle sizes were smaller in PET‐rich blends than PP‐rich blends. With increasing compatibilizer level, the refinement of morphology was observed in both the systems. However, the blends compatibilized with PTW showed a more refined (smaller) particle size, and at high PTW content (10 wt%), the morphology changed towards monophasic. The significant changes in morphology were attributed to the highly reactive nature of PTW. Investigation of rheological properties revealed that the viscosity of the PET/PP blends followed typical trends based on mixing rule, which calculates the properties of blends based on a linear average. Incorporation of PP‐g‐MA into the blends resulted in a negative deviation in the viscosity of the system with respect to that of the neat blend. With increasing PP‐g‐MA level, the deviation became more pronounced. Although incorporation of the compatibilizer into the PET/PP blends refined the morphology, it led to a drastic drop of viscosity, which could be attributed to inherently lower molecular weight of the compatibilizer. In the case of the blends compatibilized by PTW, a strong positive deviation in rheological properties was observed that confirmed the stronger interaction between the blend components due to reactive compatibilization process, which led to the more refined morphology in this series of blends. J. VINYL ADDIT. TECHNOL., 19:25–30, 2013. © 2013 Society of Plastics Engineers
Preparation and performance on polycarbonate of B/F/Si‐containing hybrid coatings
Authors: Zeytuncu Bihter , Vezir Kahraman Memet , Yücel Onuralp
Published: February 2013

A series of UV‐curable B/F/Si‐containing hybrid coatings was prepared by the anhydrous sol‐gel technique. The chemical structure of the coatings was characterized by FTIR, RTIR, and 1HNMR techniques. The UV‐curable coatings were applied to polycarbonate substrates. The physical and mechanical properties of the UV‐cured coatings, such as pendulum hardness, pencil hardness, contact angle, gel content, MEK rubbing test values, tensile strength, abrasion resistance, and gloss, were examined. Thermal gravimetric analysis (TGA) was done. The relative flammability of the hybrid coatings was tested by the limiting oxygen index (LOI) method. Results of all analyses conducted on the free films and coatings are discussed. J. VINYL ADDIT. TECHNOL., 19:39–46, 2013. © 2013 Society of Plastics Engineers
Continuous devulcanization of waste tires by using a Co‐rotating twin screw extruder: Effects of screw configuration, temperature profile, and devulcanization agent concentration
Authors: Yazdani Hamid , Ghasemi Ismaeil , Karrabi Mohammad , Azizi Hamed , Bakhshandeh Gholam Reza
Published: February 2013

Recently, for reasons both economical and environmental, recycling of waste tires based on (styrene butadiene rubber)/(natural rubber) (SBR/NR) has been widely considered. Response surface methodology (RSM) has been used to predict SBR/NR devulcanization behavior in a co‐rotating twin screw extruder. In this study, variable parameters were barrel temperature, screw configuration, and content of devulcanization agent. A Box‐Behnken design for the three variables, at three levels, was chosen. The sol fraction of devulcanized rubber, Δtorque (difference between maximum and minimum curing torque), and mechanical properties of revulcanizate samples were considered as the responses. The results indicated that an increase of devulcanization agent content at a certain temperature caused the sol fraction to increase. Samples including a higher sol fraction showed a lower cross‐link density. Sol fraction for high shear rate screw configuration was lower than that for other screw configurations. Tensile strength of revulcanized rubber showed a decrease with a rise of devulcanization temperature. Moreover, a relationship connecting the residence time in the extruder with stagger angle and length of different kneading blocks were obtained. J. VINYL ADDIT. TECHNOL., 19:65–72, 2013. © 2013 Society of Plastics Engineers
State‐space representation of the wind flow model in wind farms
Authors: Soleimanzadeh Maryam , Wisniewski Rafael , Brand Arno
Published: February 2013

A dynamic model for the wind flow in wind farms is developed in this paper. The model is based on the spatial discretization of the linearized Navier–Stokes equation combined with the vortex cylinder theory. The spatial discretization of the model is performed using the finite difference method, which provides the state‐space form of the dynamic wind farm model. The model provides an approximation of the behavior of the flow in the wind farm and obtains the wind speed in the vicinity of each wind turbine. Afterwards, the model is validated using measurement data of Energy research Center of the Netherlands’ Wind turbine Test site in Wieringermeer in the Netherlands and by employing the outcomes of two other wind flow models. The end goal of this work is to present the wind farm flow model by ordinary differential equations, to be applied in wind farm control algorithms along with load and power optimizations. Copyright © 2013 John Wiley & Sons, Ltd.
Time series factor models
Authors: Ensor Katherine Bennett
Published: February 2013

In today's data‐driven age observing a large number of variables over time for purposes of understanding the dynamics of a system is commonplace. The number of variables grows as our ability to measure, store, and retrieve data grows. Time series factor models and dynamic factor models combine data reduction and time series forecasting strategies to extract the critical information useful in forecasting a singular or small number of series from a large number of explanatory variables. Since the 1990s, these methodologies have proven a useful analytical tool in many areas of applied statistics, but most notably econometrics and finance. Furthermore, recent results in random matrix theory, which examines dimension reduction strategies as the number of variables and observations both go to infinity, have direct applicability in the area of time series factor models. This article reviews the recent history of time series factor models and demonstrates the applicability of these tools, while providing some cautionary issues through an example in the equities market. WIREs Comput Stat 2013, 5:97–104. doi: 10.1002/wics.1245

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Multivariate Analysis

Data: Types and Structure > Time Series, Stochastic Processes, and Functional Data
Challenges in model‐based clustering
Authors: Melnykov Volodymyr
Published: February 2013

Model‐based clustering is an increasingly popular area of cluster analysis that relies on probabilistic description of data by means of finite mixture models. Mixture distributions prove to be a powerful technique for modeling heterogeneity in data. In model‐based clustering, each data group is seen as a sample from one or several mixture components. Despite attractive interpretation, model‐based clustering poses many challenges. This paper discusses some of the most important problems a researcher might encounter while applying the model‐based cluster analysis.WIREs Comput Stat2013, 5:135–148. doi: 10.1002/wics.1248

This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Clustering and Classification

Statistical and Graphical Methods of Data Analysis > Density Estimation
Methods and techniques for discovering taxonomies of behavioral process models
Authors: Folino Francesco , Greco Gianluigi , Guzzo Antonella , Pontieri Luigi
Published: February 2013

Modeling behavioral aspects of business processes is a hard and costly task, which usually requires heavy intervention of business experts. This explains the increasing attention given to process mining techniques, which automatically extract behavioral process models from log data. In the case of complex processes, however, the models identified by classical process mining techniques are hardly useful to analyze business operations at a suitable abstraction level. In fact, the need of process abstraction emerged in several application scenarios, and abstraction methods are already supported in some business‐management platforms, which allow users to manually define abstract views for the process at hand. Therefore, it comes with no surprise that process mining research recently considered the issue of mining processes at different abstraction levels, mainly in the form of a taxonomy of process models, as to overcome the drawbacks of traditional approaches. This paper presents a general framework for the discovery of such a taxonomy, and offers a survey of different kinds of basic techniques that can be exploited to this purpose: (1) workflow modeling and discovery techniques, (2) clustering techniques enabling the discovery of different behavioral process classes, and (3) activity abstraction techniques for associating a generalized process model with each higher level taxonomy node. © 2013 Wiley Periodicals, Inc.

This article is categorized under:

Algorithmic Development > Association Rules

Technologies > Classification
Sulfidiodide (MSI) der schweren Lanthanoide (M = Gd – Lu): Kristallstrukturen und magnetische Eigenschaften
Authors: Blaschkowski Björn , Rosner Helge , Schnelle Walter , Schleid Thomas
Published: February 2013

From reactions of equimolar quantities of the heavier lanthanoids (M = Gd – Lu) with the elements sulfur and iodine in fused silica ampoules (900 °C, 10 d) phase‐pure samples of the lanthanoid sulfide iodides MSI (M = Gd – Lu) could be prepared. Besides the already structurally determined sulfide iodides MSI with M = Gd and Dy, all samples could be characterized by means of X‐ray powder diffraction and their magnetic behavior was examined. In addition a single‐crystal structure refinement for HoSI was carried out (orthorhombic, Pmmn; a = 415.09(4) pm, b = 531.34(5) pm, c = 920.53(9) pm), which confirmed the isotypy of the later lanthanoid sulfide iodides with the structure of FeOCl. On the basis of the X‐ray powder diffraction experiments all prepared compounds could be indexed in a primitive orthorhombic unit cell. An analysis of the determined lattice parameters and cell volumes resulted in the typical lanthanoid contraction for compounds within the row of the 4f elements. The magnetochemical studies led to the expected effective magnetic moments for trivalent lanthanoid cations without showing any magnetic ordering phenomenon.
Construction of Two Coordination Complexes Based on 5‐(4‐Pyridine N‐oxide) Tetrazole (4‐ptz) Generated by an in‐situ [2+3] Cycloaddition Reaction
Authors: Xiang Jing , Luo Ya , Wang Chun‐Hong
Published: February 2013

Solvothermal reactions of 4‐cyanopyridine N‐oxide, NaN3, and hydrated MCl2 (M = Cu, Co) in a mixture of EtOH/H2O afford the 3D polymer [CuI(4‐ptz)]n (1) and the mononuclear complex [CoII(4‐ptz)2(H2O)4] (2) (4‐ptz = 5‐(4‐pyridine N‐oxide) tetrazolate). The crystal structures of both compounds were determined by X‐ray crystallography, in which the ligand 4‐ptz exhibited different coordination modes. The thermal stability of 1 was measured by thermogravimetric analysis (TGA) and the solid state luminescence property of 1 was investigated at room temperature.
On the Synthesis and Coordination Properties of N‐Aryl‐substituted 1, 3, 2‐Diazaphospholidine‐4, 5‐diimines
Authors: Mourgas Georgios , Tiritiris Ioannis , Nieger Martin , Gudat Dietrich
Published: February 2013

New 1, 3, 2‐diazaphospholidine‐4, 5‐diimines were synthesized by condensation of lithiated oxalamidines with PCl3 or PhPCl2, and characterized by spectral and analytic data. The products react selectively with [(nbd)W(CO)4], [Mo(CO)6], or [(PhCN)2PdCl2] to give stable complexes, in which the heterocycle binds as chelating, bidentate ligand through the nitrogen atoms of the diimine unit. Formation of P‐bound or dinuclear complexes was not observed. Reaction with PCl3 or AsCl3 in the presence of SnCl2 as reducing agent was unspecific. Evidence for the formation of bicyclic products arising from formal [4+1] cycloaddition between the diimine unit and a transient pnictogen(I) species was not obtained, and only a diimine complex of SnCl4 was isolated in moderate yield. Single‐crystal X‐ray diffraction studies reveal that coordination of the diimine unit induces a substantial structural distortion of the ligand framework, which allows to explain the occurrence of substantial 31P coordination shifts despite the absence of a direct metal‐phosphorus bond.
An analysis of the influence of background subtraction and quenching on jet observables in heavy-ion collisions
Authors: Apolinário Liliana , Armesto Néstor , Cunqueiro Leticia
Published: February 2013

Abstract

Subtraction of the large background in reconstruction is a key ingredient in jet studies in high-energy heavy-ion collisions at RHIC and the LHC. Here we address the question to which extent the most commonly used subtraction techniques are able to eliminate the effects of the background on the most commonly discussed observables at present: single inclusive jet distributions, dijet asymmetry and azimuthal distributions. We consider two different background subtraction methods, an area-based one implemented through the FastJet package and a pedestal subtraction method, that resemble the ones used by the experimental collaborations at the LHC. We also analyze different ways of defining the optimal parameters in the second method. We use a toy model that easily allows variations of the background characteristics: average background level and fluctuations and azimuthal structure, but cross-checks are also done with a Monte Carlo simulator. Furthermore, we consider the influence of quenching using Q-PYTHIA on the dijet observables with the different background subtraction methods and, additionally, we examine the missing momentum of particles. The average background level and fluctuations affect both single inclusive spectra and dijet asymmetries, although differently for different subtraction setups. A large azimuthal modulation of the background has a visible effect on the azimuthal dijet distributions. Quenching, as implemented in Q-PYTHIA, substantially affects the di-jet asymmetry but little the azimuthal dijet distributions. Besides, the missing momentum characteristics observed in the experiment are qualitatively reproduced by Q-PYTHIA.
S‐adenosylmethionine and S‐adenosylhomocysteine in plasma and cerebrospinal fluid in Rett syndrome and the effect of folinic acid supplementation
Authors: Hagebeuk Eveline E. O. , Duran Marinus , Abeling Nico G. G. M. , Vyth Arno , Poll‐The Bwee Tien
Published: February 2013

Rett syndrome is a neurodevelopmental disorder characterized by cognitive and locomotor regression and stereotypic hand movements. The disorder is caused by mutations in the X chromosomal MECP2 a gene encoding methyl CpG‐binding protein. It has been associated with disturbances of cerebral folate homeostasis, as well as with speculations on a compromised DNA‐methylation. Folinic acid is the stable form of folate. Its derived intermediate 5‐MTHF supports the conversion of homocysteine to methionine, the precursor of S‐adenosylmethionine (SAM). This in turn donates its methyl group to various acceptors, including DNA, thereby being converted to S‐adenosylhomocysteine (SAH). The SAM/SAH ratio reflects the methylation potential. The goal of our study was to influence DNA methylation processes and ameliorate the clinical symptoms in Rett syndrome. Therefore we examined the hypothesis that folinic acid supplementation, besides increasing cerebrospinal fluid (CSF) 5‐MTHF (p = 0.003), influences SAM and SAH and their ratio. In our randomized, double‐blind crossover study on folinic acid supplementation, ten female Rett patients received both folinic acid and placebo for 1 year each. It was shown that both SAM and SAH levels in the CSF remained unchanged following folinic acid administration (p = 0.202 and p = 0.097, respectively) in spite of a rise of plasma SAM and SAH (p = 0.007; p = 0.009). There was no significant change in the SAM/SAH ratio either in plasma or CSF. The apparent inability of Rett patients to upregulate SAM and SAH levels in the CSF may contribute to the biochemical anomalies of the Rett syndrome. Our studies warrant further attempts to promote DNA methylation in the true region of interest, i.e. the brain.
Screening and Profiling of Hydrocarbon Components and Squalene in Developing Tunisian Cultivars and Wild Arachis hypogaea L. Species
Authors: Cherif Aïcha O. , Ben Messaouda Mhamed , Pellerin Isabelle , Boukhchina Sadok , Kallel Habib , Pepe Claude
Published: February 2013

Total hydrocarbon composition and content of whole peanuts from three Tunisian varieties of peanut (two cultivars: AraC (Virginia type), AraT (Valencia type) and a wild one: AraA) were investigated during maturation. The results show that 30 hydrocarbons were identified from the wild AraA species, while only 27 hydrocarbon were detected in the cultivar ones. The hydrocarbon fraction is essentially composed of squalene, n‐alkenes especially nC14=, nC16=, nC18=, nC20= and nC22=, n‐alkanes such as nC16, nC17, nC18, nC25, nC26 and nC27, and branched saturated hydrocarbon noted (HC1, HC2 and HC3). Among the hydrocarbon components, generally the wild variety AraA presents the highest content of phytochemical squalene during maturation, whereas a maximum was detected from cultivar AraT at 12 days after podding (815.45 mg/100 g of oil). At maturity, the maximum level is reached at about 346.74 mg/100 g of oil for AraA. During maturity, wild AraA is considered to be an excellent source of squalene like olive and pumpkin oil.
A Statistical Study on Force-Freeness of Solar Magnetic Fields in the Photosphere
Authors: Liu S. , Su J. T. , Zhang H. Q. , Deng Y. Y. , Gao Y. , Yang X. , Mao X. J.
Published: February 2013

It is an indisputable fact that solar magnetic fields are force-free in the corona, where force-free fields mean that current and magnetic fields are parallel and there is no Lorentz force in the fields. While the force-free extent of photospheric magnetic fields remains open, in this paper, we give its statistical results. Vector magnetograms (namely, Bx, By, and Bz in heliocentric coordinates) employed are observed by the Solar Magnetic Field Telescope at Huairou Solar Observing Station. We study and calibrate 925 magnetograms calibrated by two sets of calibration coefficients, which indicate the relation between magnetic fields and the strength of the Stokes spectrum and can be calculated either theoretically or empirically. The statistical results show that the majority of active region magnetic fields are not consistent with the force-free model.
Characterisation of the Optical Turbulence at Siding Spring
Authors: Goodwin Michael , Jenkins Charles , Lambert Andrew
Published: February 2013

Measurements of the optical turbulence profile above Siding Spring Observatory were conducted during 2005 and 2006. This effort was largely motivated by the need to predict the statistical performance of adaptive optics at Siding Spring. The data were collected using a purpose-built instrument based on the slope detection and ranging (SLODAR) method where observations of a bright double star are imaged by Shack–Hartmann taken with the Australian National University 24-inch and 40-inch telescopes. The analysis of the data yielded a model consisting of a handful of statistically prominent thin layers that are statistically separated into the ground layer (37.5, 250 m) and the free atmosphere (1, 3, 6, 9, 13.5 km) for good (25%), typical (50%), and bad (25%) observing conditions. We found that ground-layer turbulence dominates the turbulence profile with up to 80% of the integrated turbulence below 500 m. The turbulence tends to be non-Kolmogorov, especially for the ground layer with a power-law index of β ~ 10/3. The mirror/dome seeing can be a significant fraction of the ground-layer turbulence. The median atmospheric seeing is around 1.2 arcsec, in agreement with observational reports.
Ethnic Quotas and Political Mobilization: Caste, Parties, and Distribution in Indian Village Councils
Authors: DUNNING THAD , NILEKANI JANHAVI
Published: February 2013

Ethnic quotas are often expected to induce distribution of material benefits to members of disadvantaged groups. Yet, the presence of an ethnic quota does not imply that political mobilization takes place along ethnic lines: Cross-cutting affiliations within multi-ethnic party organizations may lessen the tendency of politicians to target benefits to particular ethnic groups. In this article, we evaluate the impact of quotas for the presidencies of village councils in India, a subject of considerable recent research. Drawing on fine-grained information from surveys of voters, council members, presidents, and bureaucrats and using a natural experiment to isolate the effects of quotas in the states of Karnataka, Rajasthan, and Bihar, we find weak distributive effects of quotas for marginalized castes and tribes, but suggestive evidence of the importance of partisanship. We then use survey experiments to compare the influence of party and caste on voting preferences and expectations of benefit receipt. Our results suggest that especially when politicians have dynamic political incentives to allocate benefits along party lines, cross-cutting partisan ties can blunt the distributive impact of ethnic quotas.
THE MULTIPLIER ALGEBRA AND BSE PROPERTY OF THE DIRECT SUM OF BANACH ALGEBRAS
Authors: KAMALI ZEINAB , LASHKARIZADEH BAMI MAHMOOD
Published: February 2013

The notion of BSE algebras was introduced and first studied by Takahasi and Hatori and later studied by Kaniuth and Ülger. This notion depends strongly on the multiplier algebra $M( \mathcal{A} )$ of a commutative Banach algebra $ \mathcal{A} $. In this paper we first present a characterisation of the multiplier algebra of the direct sum of two commutative semisimple Banach algebras. Then as an application we show that $ \mathcal{A} \oplus \mathcal{B} $ is a BSE algebra if and only if $ \mathcal{A} $ and $ \mathcal{B} $ are BSE. We also prove that if the algebra $ \mathcal{A} \hspace{0.167em} {\mathop{\times }\nolimits}_{\theta } \hspace{0.167em} \mathcal{B} $ with $\theta $-Lau product is a BSE algebra and $ \mathcal{B} $ is unital then $ \mathcal{B} $ is a BSE algebra. We present some examples which show that the BSE property of $ \mathcal{A} \hspace{0.167em} {\mathop{\times }\nolimits}_{\theta } \hspace{0.167em} \mathcal{B} $ does not imply the BSE property of $ \mathcal{A} $, even in the case where $ \mathcal{B} $ is unital.
“Little Soldiers” for Socialism: Childhood and Socialist Politics in the British Socialist Sunday School Movement
Authors: Gerrard Jessica
Published: February 2013

This paper examines the ways in which turn-of-the-century British socialists enacted socialism for children through the British Socialist Sunday School movement. It focuses in particular on the movement's emergence in the 1890s and the first three decades of operation. Situated amidst a growing international field of comparable socialist children's initiatives, socialist Sunday schools attempted to connect their local activity of children's education to the broader politics of international socialism. In this discussion I explore the attempt to make this connection, including the endeavour to transcend party differences in the creation of a non-partisan international children's socialist movement, the cooption of traditional Sunday school rituals, and the resolve to make socialist childhood cultures was the responsibility of both men and women. Defending their existence against criticism from conservative campaigners, the state, and sections of the left, socialist Sunday schools mobilized a complex and contested culture of socialist childhood.
Writing a Global History of Convict Labour
Authors: De Vito Christian G. , Lichtenstein Alex
Published: February 2013

This bibliographic essay seeks to contribute to the understanding of convict labour from a global and long-term perspective. First the conditions conducive to the emergence and transformation of convict labour are addressed by framing this coercive labour form within broader classifications of labour relations and by discussing its connection with the problem of governmentality. Subsequently, an overview of the literature is undertaken in the form of a journey across time, space, and different regimes of punishment. Finally, the limitations of the available literature are discussed, the possibility of a longer-term (pre-1500) and global history of convict labour is considered, and some theoretical and methodological approaches are suggested that could favour this task.
The effect of arbuscular mycorrhizal fungi on total plant nitrogen uptake and nitrogen recovery from soil organic material
Authors: SAIA S. , BENÍTEZ E. , GARCÍA-GARRIDO J. M. , SETTANNI L. , AMATO G. , GIAMBALVO D.
Published: February 2013

Arbuscular mycorrhizal (AM) fungi increase nitrogen (N) uptake by their host plants, but their role in plant N capture from soil organic material is still unclear. In particular, it is not clear if AM fungi compete with the host plant for the N coming from the decomposing organic matter (OM), especially when the AM extraradical mycelium (ERM) and plant roots share the same soil volume. The goal of the present research was to study the effects of AM fungi on wheat N capture after the addition of15N-labelled OM to soil. Durum wheat (Triticum durum) was grown under controlled conditions in a sand:soil mix and the following treatments were applied: (1) AM inoculation withGlomus mosseaeand uninoculated control; and (2) soil amended with15N-enriched maize leaves and unamended soil. The addition of OM reduced plant growth and N uptake. The AM fungi increased both plant growth and N uptake compared with uninoculated control plants and the effect was enhanced when wheat was grown in soil amended with OM compared with the unamended control. Although AM fungi increased soil N mineralization rates and total plant N uptake, they strongly reduced wheat N recovery from OM, suggesting that AM fungi have marked effects on competition between plants and bacteria for the different N sources in soil.
Impact du sentiment de dépendance aux benzodiazépines sur l’utilisation des services de santé : Étude sur la santé des aînés
Authors: Mengue Pamphile-Gervais Nkogho , Abdous Belkacem , Berbiche Djamal , Préville Michel , Voyer Philippe
Published: February 2013

Contexte :La consommation de benzodiazépines est une pratique courante chez les personnes aînées. Cette consommation peut entraîner un problème de dépendance dont les critères duManuel diagnostic et statistique des troubles mentaux, 4eédition révisée(DSM-IV-TR) ne s’appliqueraient pas toujours à la situation de l’aîné. Cette recherche vise à examiner l’association entre le sentiment de dépendance aux benzodiazépines et l’utilisation des services de santé par les aînés. Un objectif secondaire consiste à décrire l’utilisation des benzodiazépines chez les aînés vivant dans la communauté.

Méthode :Les données proviennent d’une enquête menée au Québec en 2005-2006 auprès d’un échantillon représentatif de 707 francophones âgés de 65 ans et plus vivant dans la communauté. Le sentiment de dépendance aux benzodiazépines a été évalué par une variable composite intégrant deux questions inspirées du DSM-IV-TR. L’utilisation des services de santé a été mesurée par l’incidence cumulée des consultations auprès des professionnels de la santé au cours d’une période de 12 mois.

Résultats :Les aînés ont consommé au total 745 benzodiazépines parmi lesquelles 117 (16,5 %) avaient une longue demi-vie d’élimination. La proportion d’aînés qui ont rapporté un sentiment de dépendance aux benzodiazépines a été estimée à 35,1 %. Ces aînés n’ont pas significativement davantage utilisé les services de santé pour leurs problèmes de dépendance aux benzodiazépines.

Conclusion :Les résultats de cette étude suggèrent que l’utilisation des benzodiazépines chez les aînés au Québec est loin d’être optimale. Par ailleurs, le besoin ressenti de dépendance ne constitue pas un facteur suffisant pour amener les aînés à utiliser les services de santé pour la prise en charge d’un problème de dépendance. Il existe donc un besoin de recherche afin de mieux cerner les barrières associées à l’utilisation des services de santé par les aînés dépendants aux benzodiazépines.
Interpolation of spatial data – A stochastic or a deterministic problem?
Authors: SCHEUERER M. , SCHABACK R. , SCHLATHER M.
Published: February 2013

Interpolation of spatial data is a very general mathematical problem with various applications. In geostatistics, it is assumed that the underlying structure of the data is a stochastic process which leads to an interpolation procedure known as kriging. This method is mathematically equivalent to kernel interpolation, a method used in numerical analysis for the same problem, but derived under completely different modelling assumptions. In this paper we present the two approaches and discuss their modelling assumptions, notions of optimality and different concepts to quantify the interpolation accuracy. Their relation is much closer than has been appreciated so far, and even results on convergence rates of kernel interpolants can be translated to the geostatistical framework. We sketch different answers obtained in the two fields concerning the issue of kernel misspecification, present some methods for kernel selection and discuss the scope of these methods with a data example from the computer experiments literature.
Calcifying fibrous tumour originating from the right cardiac ventricle in a child
Authors: Zhang Ben , Zhang Weida , Wang Xiaowu
Published: February 2013

Calcifying fibrous tumour is a rare benign fibrous lesion. It is paucicellular, with fibroblasts, dense collagenisation, psammomatous and dystrophic calcification, and patchy lymphoplasmacytic infiltrates. Calcifying fibrous tumour was first described in subcutaneous and deep soft tissues, and has been reported all over the body. However, calcifying fibrous tumour originating from the heart is extremely rare. This article describes the case of a giant calcifying fibrous tumour arising from the right ventricle in a child, where the tumour was totally resected and no recurrence was observed during a 4-year follow-up period.
Effect of Preschool Working Memory, Language, and Narrative Abilities on Inferential Comprehension at School-Age in Children with Spina Bifida Myelomeningocele and Typically Developing Children
Authors: Pike Meredith , Swank Paul , Taylor Heather , Landry Susan , Barnes Marcia A.
Published: February 2013

Children with spina bifida myelomeningocele (SBM) are more likely to display a pattern of good-decoding/poor comprehension than their neurologically intact peers. The goals of the current study were to (1) examine the cognitive origins of one of the component skills of comprehension, bridging inferences, from a developmental perspective and (2) to test the effects of those relations on reading comprehension achievement. Data from a sample of children with SBM and a control group (n = 78) who participated in a longitudinal study were taken from age 36-month and 9.5-year time points. A multiple mediation model provided evidence that three preschool cognitive abilities (working memory/inhibitory control, oral comprehension, narrative recall), could partially explain the relation between group and bridging inference skill. A second mediation model supported that each of the 36-month abilities had an indirect effect on reading comprehension through bridging inference skill. Findings contribute to an understanding of both typical and atypical comprehension development, blending theories from the developmental, cognitive, and neuropsychological literature. (JINS, 2013, 19, 1–10)
Impact of iron-fortified foods on Hb concentration in children (<10 years): a systematic review and meta-analysis of randomized controlled trials
Authors: Athe Ramesh , Rao M Vishnu Vardhana , Nair K Madhavan
Published: February 2013

Objective

To combine evidence from randomized controlled trials to assess the effect of Fe-fortified foods on mean Hb concentration in children (<10 years).

Design

We conducted a meta-analysis of randomized, controlled, Fe-fortified feeding trials that evaluated Hb concentration. The weighted mean difference was calculated for net changes in Hb by using random-effects models. Meta-regression and covariate analyses were performed to explore the influence of confounders on the net pooled effect.

Setting

Trials were identified through a systematic search of PubMed, the Cochrane Library and secondary references.

Subjects

Eighteen studies covering 5142 participants were identified. The duration of feeding of fortified foods ranged from 6 to 12 months in these studies.

Results

Eighteen studies were included and evaluated in the meta-analysis. The overall pooled estimate of Hb concentration showed a significant increase in the fortification group compared with the control group (weighted mean difference = 5·09 g/l; 95 % CI 3·23, 6·95 g/l;I2= 90 %,τ2= 18·37,P< 0·0001). Meta-regression analysis indicated that duration of feeding was positively related to the effect size (regression coefficient = 0·368; 95 % CI 0·005, 0·731;P< 0·05). The net pooled effect size after removing the confounders was 4·74 (95 % CI 3·08, 6·40) g/l.

Conclusions

We observed an association between intake of Fe-fortified foods and Hb concentration in children aged <10 years. Fe-fortified foods could be an effective strategy for reducing Fe-deficiency anaemia in children.
OPTIMAL CONTROL OF SWITCHED IMPULSIVE SYSTEMS WITH TIME DELAY
Authors: WONG K. H. , TANG W. M.
Published: February 2013

We develop a computational method for solving an optimal control problem governed by a switched impulsive dynamical system with time delay. At each time instant, only one subsystem is active. We propose a computational method for solving this optimal control problem where the time spent by the state in each subsystem is treated as a new parameter. These parameters and the jump strengths of the impulses are decision parameters to be optimized. The gradient formula of the cost function is derived in terms of solving a number of delay differential equations forward in time. Based on this, the optimal control problem can be solved as an optimization problem.
A HYBRID MODEL FOR STUDYING SPATIAL ASPECTS OF INFECTIOUS DISEASES
Authors: BINDER BENJAMIN J. , ROSS JOSHUA V. , SIMPSON MATTHEW J.
Published: February 2013

We consider a hybrid model, created by coupling a continuum and an agent-based model of infectious disease. The framework of the hybrid model provides a mechanism to study the spread of infection at both the individual and population levels. This approach captures the stochastic spatial heterogeneity at the individual level, which is directly related to deterministic population level properties. This facilitates the study of spatial aspects of the epidemic process. A spatial analysis, involving counting the number of infectious agents in equally sized bins, reveals when the spatial domain is nonhomogeneous.
CONTINUED FRACTIONS FOR A CLASS OF TRIANGLE GROUPS
Authors: CALTA KARIANE , SCHMIDT THOMAS A.
Published: February 2013

We give continued fraction algorithms for each conjugacy class of triangle Fuchsian group of signature $(3, n, \infty )$, with $n\geq 4$. In particular, we give an explicit form of the group that is a subgroup of the Hilbert modular group of its trace field and provide an interval map that is piecewise linear fractional, given in terms of group elements. Using natural extensions, we find an ergodic invariant measure for the interval map. We also study Diophantine properties of approximation in terms of the continued fractions and show that these continued fractions are appropriate to obtain transcendence results.
APPROXIMATION OF AN ALGEBRAIC NUMBER BY PRODUCTS OF RATIONAL NUMBERS AND UNITS
Authors: LEVESQUE CLAUDE , WALDSCHMIDT MICHEL
Published: February 2013

We relate a previous result of ours on families of Diophantine equations having only trivial solutions with a result on the approximation of an algebraic number by products of rational numbers and units. We compare this approximation with a Liouville type estimate, and with an estimate arising from a lower bound for a linear combination of logarithms.
Consistency of symptom clusters among advanced cancer patients seen at an outpatient supportive care clinic in a tertiary cancer center
Authors: Yennurajalingam Sriram , Kwon Jung Hye , Urbauer Diana L. , Hui David , Reyes-Gibby Cielito C , Bruera Eduardo
Published: February 2013

Objective:

Advanced cancer patients often develop severe physical and psychological symptom clusters (SCs), but limited data exist on their consistency or severity after an outpatient interdisciplinary team consultation led by palliative care specialists. The primary aim of the study was to determine the consistency and severity of SCs in advanced cancer patients in this setting.

Method:

A total of 1373 patients with advanced cancer who were referred to The University of Texas MD Anderson Cancer Center's Outpatient Supportive Care Center between January 2003 and October 2008 with a complete Edmonton Symptom Assessment Scale (ESAS; 0–10 scale) occurred at initial and first follow-up visit were reviewed (median 14 days, range 1–4 weeks). We used a Wilcoxon signed-rank test to determine whether symptoms changed over time, and a principal components factor analysis with varimax rotation to determine SCs at baseline and at first follow-up. The number of factors calculated was determined based upon the number of eigenvalues.

Results:

The patients' ratings of the following symptoms (mean, SD) at the initial and follow-up visits, respectively, were: fatigue 6.2 (2.3) and 5.7 (2.5, p < 0.0001), pain 5.4 (2.9) and 4.6 (3, p < 0.0001), nausea 2.2 (2.8) and 2.0 (2.6, p < 0.0001), depression 3.0 (2.9) and 2.5 (2.7, p < 0.0001), anxiety 3.4 (3.0) and 2.8 (2.8, p < 0.0001), drowsiness 4.8 (3.1) and 4.4 (3.1, p < 0.0001), dyspnea 3.0 (2.9) and 2.7 (2.8), p < 0.0001), loss of appetite 4.2 (2.7) and 3.9 (2.7, p < 0.0001), sleep disturbances 4.2 (2.6) and 3.8 (2.6, P < 0.0001), and well-being 4.3 (2.5) and 3.9 (2.3, p < 0.0001). Cluster composition differentiated into physical (fatigue, pain, nausea, drowsiness, dyspnea, and loss of appetite) and psychological (anxiety and depression) components at the initial visit, and these two SCs were consistent upon follow-up.

Significance of results:

We conclude that SCs remain constant between baseline and near-term follow-up but that the severity of those symptoms lessened during that interval. This knowledge may allow palliative care teams to provide more targeted and higher-quality care, but further studies are needed.
Depressed patients with incurable cancer: Which depressive symptoms do they experience?
Authors: Brenne Elisabeth , Loge Jon Håvard , Kaasa Stein , Heitzer Ellen , Knudsen Anne Kari , Wasteson Elisabet
Published: February 2013

Objective:

Diagnosing depressive disorders in palliative care is challenging because of the overlap between some depressive symptoms and cancer-related symptoms, such as loss of appetite and fatigue. In order to improve future assessment of depression in palliative care, depressive symptoms experienced by patients receiving pharmacological treatment for depression were assessed and compared to the American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) criteria for major depressive disorder.

Method:

Thirty Norwegian (n = 20) and Austrian (n = 10) patients with advanced cancer were included. Semistructured interviews on symptom experiences were conducted and transcribed verbatim. By the phenomenographic method, patients' symptom experiences were extracted and sorted by headings, first individually and then across patients. The patients subsequently rated 24 symptoms numerically including the DSM-IV depression criteria.

Results:

Lowered mood and a diminished motivational drive were prominent and reflected the two main DSM-IV symptom criteria. A relentless focus on their actual situation, restlessness, disrupted sleep, feelings of worthlessness, feelings of guilt, and thoughts of death as a solution were variably experienced. Appetite and weight changes, fatigue and psychomotor retardation were indistinguishable from cancer symptoms. All these symptoms reflected DSM-IV symptom criteria. Some major symptoms occurred that are not present in the DSM-IV symptom criteria: despair, anxiety, and social withdrawal. The numerical ratings of symptoms were mainly in accordance with the findings from the qualitative analysis.

Significance of results:

Despair, anxiety, and social withdrawal are common symptoms in depressed patients with incurable cancer, and, therefore, hypothesized as candidate symptom criteria. Other symptom criteria might need adjustment for improvement of relevance in this group of patients.
Bacterial growth at −15 °C; molecular insights from the permafrost bacterium Planococcus halocryophilus Or1
Authors: Mykytczuk Nadia C S , Foote Simon J , Omelon Chris R , Southam Gordon , Greer Charles W , Whyte Lyle G
Published: February 2013

Planococcus halocryophilus strain Or1, isolated from high Arctic permafrost, grows and divides at −15 °C, the lowest temperature demonstrated to date, and is metabolically active at −25 °C in frozen permafrost microcosms. To understand how P. halocryophilus Or1 remains active under the subzero and osmotically dynamic conditions that characterize its native permafrost habitat, we investigated the genome, cell physiology and transcriptomes of growth at −15 °C and 18% NaCl compared with optimal (25 °C) temperatures. Subzero growth coincides with unusual cell envelope features of encrustations surrounding cells, while the cytoplasmic membrane is significantly remodeled favouring a higher ratio of saturated to branched fatty acids. Analyses of the 3.4 Mbp genome revealed that a suite of cold and osmotic-specific adaptive mechanisms are present as well as an amino acid distribution favouring increased flexibility of proteins. Genomic redundancy within 17% of the genome could enable P. halocryophilus Or1 to exploit isozyme exchange to maintain growth under stress, including multiple copies of osmolyte uptake genes (Opu and Pro genes). Isozyme exchange was observed between the transcriptome data sets, with selective upregulation of multi-copy genes involved in cell division, fatty acid synthesis, solute binding, oxidative stress response and transcriptional regulation. The combination of protein flexibility, resource efficiency, genomic plasticity and synergistic adaptation likely compensate against osmotic and cold stresses. These results suggest that non-spore forming P. halocryophilus Or1 is specifically suited for active growth in its Arctic permafrost habitat (ambient temp. ∼−16 °C), indicating that such cryoenvironments harbor a more active microbial ecosystem than previously thought.
Safety of Food Additives in Europe
Authors: Barlow Susan M
Published: February 2013

The use of additives in foods traded within the EU is strictly controlled by legislation, which can be amended to include newly approved additives or to delete additives that are no longer approved. Food additives can only be approved for inclusion in EU permitted lists by decision of the European Commission and Member States, which are the risk managers. Before making any approvals, a full risk assessment is carried out by the European Food Safety Authority (EFSA), which advises the risk managers. EFSA considers all safety aspects of an additive, including technical toxicological and exposure data. If there are no safety concerns, EFSA sets an acceptable daily intake (ADI). The ADI is compared with estimates of overall exposure to the food additive, which include both average and high exposure estimates for the population and relevant sub-groups. If estimated exposure exceeds the ADI, it is the task of the risk managers to impose any necessary restrictions on the uses and use levels of the additive in foods. Once marketed, the monitoring of consumer intakes of food additives by the Member States enables checks to be carried out to ensure ADIs are not being exceeded. EFSA is also conducting a re-evaluation of all currently permitted food additives on the EU market that includes consideration of all published literature and documentation submitted by manufacturers and other interested parties. This has already resulted in some additives being removed from the permitted lists and in the lowering or raising of ADIs set previously.
Legislation for Food Additives Outside Europe
Authors: Richardson Vanessa , Freeman Ella , Fitzpatrick Laura , Amirat Linda , Kubo Mariko , Li Meng
Published: February 2013

Controls on the use of food additives can vary significantly from country to country and area to area, having the potential to represent a serious issue to manufacturers of food products and importers who need to purchase ingredients from different parts of the world and exporters intending to sell their products in more than one market. Different factors must be taken into consideration in the development of food legislation related to additives, including technological need and safety. The Codex Alimentarius Commission (CAC) and its Committees, through the work with the Joint Food and Agriculture Organization (FAO)/World Health Organization (WHO) Expert Committee on Food Additives (JECFA) are responsible, at international level, for the evaluation of food additives to ensure they are safe for consumption taking into consideration patterns of consumption of the foods in which additives are used. Therefore, the work of the Codex Alimentarius has a severe impact on the development of food legislation worldwide, together with the work of regional bodies, such as the European Union (EU) bodies. The use of food additives also follows trends led by consumer perception. The aim of this chapter is to assess food additive controls and key aspects of international food law or guidance laid down in several countries/regions and international bodies, namely the Codex Alimentarius, the USA, Canada, Japan and certain Far East countries, the Southern Common Market (MERCOSUR), the Middle East and Australia/New Zealand, with the aim of highlighting some of the main differences.