bluuebunny/crossref_metadata_2025 huggingface dataset:
Intelligence Impairment, Personality Features and Psychopathology Disturbances in a Family Affected with CADASIL
Authors: Domínguez-Sánchez Francisco Javier , Lasa-Aristu Amaia , Goñi-Imízcoz Miguel
Published: November 2011

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a small-vessel disease of the brain that is characterized by headache, recurring lacunar strokes, mood changes and progressive cognitive deterioration. The disease is transmitted with an autosomal dominant pattern and usually starts during midadulthood (at 30–50 years of age). Cognitive deficits in patients with CADASIL develop slowly. The dementia causes frontal-like symptoms and it typically develops after a history of recurrent stroke. We describe three patients from one Spanish family affected by this disease. All three cases underwent comprehensive clinical and neuropsychological examination, and were monitored for seven years. The results obtained in this study describe a) a significant loss of the intelligence quotient (IQ) and noticeable damage to abstract ability (g factor), b) mood and psychopathological disturbances (major depression and dysthymia), and c) a personality with neurotic features.
Psychometric Analysis of the Catalan Version of the Alabama Parenting Questionnaire (APQ) in a Community Sample
Authors: Molinuevo Beatriz , Pardo Yolanda , Torrubia Rafael
Published: November 2011

The aim of this study was to adapt to Catalan the parents' and children's global report forms of the Alabama Parenting Questionnaire (APQ), using a community sample of 364 children between 10 and 15 years old and their families. Sociodemographic information (from parents) and the presence of externalizing problems (from parents and teachers) were collected. The results suggest a 3-factor structure corresponding to the scales of Positive Parenting Practices (PPP), Inconsistent and Negative Discipline (IND) and Poor Monitoring/Supervision (PMS). The internal consistency is acceptable in all the scales, except for the IND in the children's format. The scales also present good convergent and discriminant validity, and the relations with the external variable studied pointed in the expected direction: inefficient parenting practices are related to the presence of more behavior problems in children. To sum up, the Catalan version of the parents' and children's global report forms of the APQ are considered suitable for use in the area of children's and adolescents' behavior problems.
The Use of the Effect Size in JCR Spanish Journals of Psychology: From Theory to Fact
Authors: García Juan García , Campos Elena Ortega , Sánchez Leticia De la Fuente
Published: November 2011

In 1999, Wilkinson and the Task Force on Statistical Inference published “Statistical Methods and Psychology: Guidelines and Explanation.” The authors made several recommendations about how to improve the quality of Psychology research papers. One of these was to report some effect-size index in the results of the research. In 2001, the fifth edition of thePublication Manual of the American Psychological Associationincluded this recommendation. In Spain, in 2003, scientific journals likePsicothemaor theInternational Journal of Clinical and Health Psychology(IJCHP) published editorials and papers expressing the need to calculate the effect size in the research papers. The aim of this study is to determine whether the papers published from 2003 to 2008 in the four Spanish journals indexed in theJournal Citation Reportshave reported some effect-size index of their results. The findings indicate that, in general, the follow-up of the norm has been scanty, though the evolution over the analyzed period is different depending on the journal.
Effects of a Play Program on Creative Thinking of Preschool Children
Authors: Garaigordobil Maite , Berrueco Laura
Published: November 2011

The purpose of this study was to evaluate the effects of a play program in the creative thinking of preschool children. The study used a repeated measures experimental pretest-posttest design with control groups. The sample included 86 participants aged 5 to 6 years (53 experimental and 33 control participants). Before and after administering the program, two evaluation instruments were applied: The Torrance Test of Creative Thinking (Torrance, 1990) and Behaviors and Traits of Creative Personality Scale (Garaigordobil & Berrueco, 2007). The program consisted of a weekly 75-minute play session throughout the school year. ANOVA results showed that the program significantly increased the verbal creativity (fluency, flexibility, originality), graphic creativity (elaboration, fluency, originality), and behaviors and traits of creative personality. In the pretest phase, there were no differences in the creativity of boys and girls, and the program stimulated a similar level of change in both sexes. The discussion focuses on the importance of implementing creative programs with preschool children.
The Role of External Interaction for Innovation in Irish High-Technology Businesses
Authors: Jordan Declan , O'Leary Eoin
Published: November 2011

There is growing empirical evidence that external interaction is an important source of knowledge for business innovation. This paper contributes to the innovation literature by using new measures of interaction to explore the relative importance of external interaction for innovation in Irish high-technology businesses. Based on survey data, the paper finds that external interaction increases the probability of product and process innovation, but the effect is inconsistent across all external interaction agents. Interaction along the supply chain has a positive effect on innovation, and interaction with competitors has an insignificant effect on innovation output. Notably, the paper finds that interaction with higher education institutions has a negative effect on the probability of product and process innovation.
Interorganizational Networks and Open Innovation Environments
Authors: Munoz Pablo , Lu Lucy
Published: November 2011

This paper examines the formation, structuring and internal dynamics of networks in an open innovation environment. Based on a case study conducted at the Creapolis Innovation Centre in Spain, it highlights the significance of several paradoxes which emerge from the interaction between organizations that share an open environment. These paradoxes have been shown to compromise the stability and performance of an effective innovation network and to represent a double-edged sword that may both facilitate and constrain the development of the innovative capacities of firms. This paper stresses the importance of a deeper understanding of such critical issues, and suggests mechanisms for creating and facilitating an appropriate and effective open innovation environment, in which knowledge is shared and exchanged between innovation actors.
Qualitative research approach in production engineering – an assessment of a research project and a sample of master of science dissertations
Authors: Miguel Paulo Cauchick
Published: November 2011

This paper aims at demonstrating applications of qualitative research approaches in the subject of operations management (OM), more specifically in the practical field of industrial engineering. It firstly presents a brief review of research methods when using a qualitative research approach. This provides the backdrop for a content analysis of qualitative research in a research project in which a case study approach was employed. In addition, it analyses a sample of dissertations of a post graduate program in industrial engineering with regard to the qualitative research approaches used. These two cases highlighted are then used as the basis for a discussion of qualitative research in OM. The paper concludes that critical appraisal of qualitative research is needed and provides some recommendations for future work in this direction.
Turbulent mixed flow applying CFD in electronic cooling
Authors: Chaves Carlos Alberto , Correa Valesca Alves , Camargo José Rui , Nunes Luiz Eduardo Nicolini do Patrocinio , Lamas Wendell De Queiróz
Published: November 2011

The thermal analysis of electronic equipment relies significantly on the use of Computational Fluid Dynamics (CFD) software to predict component heat dissipation. The commercial software CFX was used in order to analyse the thermal parameters in electronic equipment where several values of velocity were explored in a model with a turbulent mixed forced cooling flow. The finite-volume method has been used to solve the problem equations throughout the physical domain with the standard k-є turbulence model. To the numerical simulations there were analysed the maximum temperature in function of the heat flux and injection velocity to laminar and turbulent flow and the visualization could also help with the selection of a numerical flow modelling strategy.
Reuse of effluent from dyeing polyester fibers by thermal fixation using acid-based colors
Authors: Fujisawa Ronaldo Shiguemi , Lamas Wendell De Queiróz
Published: November 2011

This paper presents the viability study of water reuse in the seat belt webbing dyeing process, reaching a great economy in the water consumption since the textile operation uses a great amount of water. To achieve this goal, it was tested several products during the effluent treatment that contains biodegradable characteristics and greater efficiency to remove color, also attending to effective legislation and low cost expectation. Using these new products, water consumption was reduced approximately 59% in a month and effluent treatment around 30%. Based on these initial results, is expected to have a payback in approximately five months.
Análises técnica, econômica e financeira da modernização de sistema de cogeração: um estudo de caso
Authors: Pinto Marco Antonio Outeiro , Ferreira Maurício Lamano
Published: November 2011

A utilização de fontes alternativas vem ganhando importância nas discussões mundiais sobre o abastecimento de energia. Dentre estas fontes está a biomassa, que é uma fonte renovável e que contribui para a redução do efeito estufa. O bagaço de cana de açúcar é uma biomassa abundante no Brasil, sendo um combustível muito utilizado em sistemas de cogeração. Empresas, grandes consumidoras de energia, vêm optando por utilizar sistemas de cogeração, a fim de tornarem-se mais competitivas, suprindo suas necessidades energéticas e permitindo a venda do excedente de energia. Neste trabalho foi realizado um estudo de caso voltado ao redimensionamento do sistema de cogeração de energia em uma empresa. Foram analisadas as condições técnicas, econômicas e financeiras de duas propostas para este redimensionamento, a fim de fornecer subsídios para a escolha do melhor investimento. Concluiu-se que a substituição do sistema de geração de energia atual por um mais eficiente é suficiente para suprir a demanda energética da empresa e ainda permitir um excedente de energia elétrica. As análises financeiras comprovaram que o empreendimento pode vir a ser implementado, visto que os resultados satisfazem as atuais condições de um potencial financiamento.
O processo de divulgação de recall: as práticas da indústria automobilística e a influência na resposta do consumidor
Authors: Silva Ivan Luiz Laranjeiras , Calarge Felipe Araujo , Rosa Fernando Pedro
Published: November 2011

Dados concretos da indústria automotiva no Brasil mostram que a produção de veículos automotores já passa dos três milhões, e traça uma trajetória ascendente no volume de produção desde 2004, figurando atualmente como sexta maior produtora do mundo. Todo esse extenso mercado consumidor está suscetível a variabilidade na qualidade do produto, quando neste ocorrem defeitos que extrapolam as barreiras internas do fabricante. Quando este defeito é nocivo para segurança e saúde do usuário, o fabricante do produto tem a responsabilidade de realizar uma campanha informativa ao público consumidor referente ao defeito em questão, o que denomina-se Recall. Visando melhor compreender a forma como o anúncio e a divulgação de um Recall acontece na indústria automotiva, esta pesquisa apontou que a principal forma de divulgação é através da comunicação impressa e que algumas empresas não divulgam os dados referentes aos Recalls em seu sítios da internet.
Synthesis of Ti2SnC MAX Phase by Mechanical Activation and Melt Infiltration
Authors: Kang Young Jae , Fey Tobias , Greil Peter
Published: November 2011

Ternary MAX phase Ti2SnC was synthesized by Sn‐melt infiltration into a porous preform of sub‐stoichiometric titanium carbide TiC0.5. Compared to synthesis starting from elemental Ti + C + Sn mixtures which require temperatures exceeding 1100 °C a significantly lower reaction temperature as low as 700 °C was observed in the TiC0.5 + Sn system. This reduction in reaction temperature is rationalized in terms of accumulation of microstrain and decrease of crystallite size upon ball milling of the Ti + C powder mixture. Dense compacts of Ti2SnC with only minor fractions of unreacted TiC0.5 were obtained at 1025 °C. Thus reactive solid–liquid processing at lower temperatures might be of relevance for MAX phase systems containing low melting A‐elements such as Sn, In, Ga, Pb, etc. which tend to become unstable at elevated temperatures.
Decomposition strategy for the global optimization of flexible energy polygeneration systems
Authors: Chen Yang , Li Xiang , Adams Thomas A. , Barton Paul I.
Published: November 2011

The optimal design and operation of flexible energy polygeneration systems using coal and biomass to coproduce power, liquid fuels, and chemicals are investigated. This problem is formulated as a multiperiod optimization problem, which is a potentially large‐scale nonconvex mixed‐integer nonlinear program (MINLP) and cannot be solved to global optimality by state‐of‐the‐art global optimization solvers, such as BARON, within a reasonable time. A duality‐based decomposition method, which can exploit the special structure of this problem, is applied. In this work, the decomposition method is enhanced by the introduction of additional dual information for faster convergence. The enhanced decomposition algorithm (EDA) guarantees to find an ε‐optimal solution in a finite time. The case study results show that the EDA achieves much faster convergence than both BARON and the original decomposition algorithm, and it solved the large‐scale nonconvex MINLPs to ε‐optimality in practical times. © 2011 American Institute of Chemical Engineers AIChE J, 58: 3080–3095, 2012
Blocked polyisocyanates containing fluorine atoms as crosslinking agents for polyurethane powder coatings
Authors: Pilch‐Pitera Barbara
Published: November 2011

Using alicyclic diisocyanates (HDI, TMDI, IPDI, H12MDI), aliphatic unfluorinated and fluorinated alcohols, dibutyltin dilaurate as well as triethylamine as catalysts, blocked polyisocyanate crosslinkers for powder lacquers were synthesized. The chemical structure of these compounds was characterized by means of IR, 1H‐NMR, 13C‐NMR, and 19F‐NMR spectroscopy. Their molecular weight distribution parameters were determined by gel permeation chromatography. These blocked polyisocyanates were used for the production of powder lacquer compositions and coatings. The three‐dimensional surface topography and surface chemical structure of the resulting powder lacquers were investigated by means of confocal microscope and ATR FT‐IR. The values of surface roughness parameters were calculated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of annealing temperature on phase composition and tensile properties in isotactic poly(1‐butene)
Authors: Chvátalová Lenka , Beníček Lubomír , Berková Kristýna , Čermák Roman , Obadal Martin , Verney Vincent , Commereuc Sophie
Published: November 2011

The influence of annealing temperature on the kinetics of polymorphic changes and mechanical properties within the time in isotactic poly(1‐butene) (PB‐1) has been investigated by wide‐angle X‐ray scattering and tensile testing. Extruded tapes of PB‐1 have been exposed to several annealing temperatures: −22, +5, +22, +40 and +60°C. The evolution of content of Phase I for various annealing temperatures upon time shows predominantly S‐shaped trend. Annealing temperature considerably affects the overall rate of transformation in PB‐1. On the other hand, the resulting mechanical properties are solely controlled by the polymorphic composition. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Microwave dielectric properties of flexible butyl rubber–strontium cerium titanate composites
Authors: Janardhanan Chameswary , Thomas Dhanesh , Subodh Ganesanpotti , Harshan Soumya , Philip Jacob , Sebastian Mailadil T.
Published: November 2011

Butyl rubber–strontium cerium titanate (BS) composites have been prepared by hot pressing. The tensile tests show that the BS composites are flexible. The dielectric properties of the composites have been investigated at 1 MHz and 5 GHz as a function of ceramic contents. The composite with volume fraction 0.43 of ceramic filler has a dielectric constant (εr) of 11.9 and dielectric loss (tan δ) 1.8 × 10−3 at 5 GHz. The measured values of εr are compared with the effective values calculated using different theoretical models. The thermal conductivity of the composites is found to increase with ceramic contents and reaches a value of 4.5 Wm−1 K−1 for maximum filler loading 0.43 volume fraction. The coefficient of thermal expansion of the composites decreases gradually with filler loading and reaches a minimum value of 30.2 ppm °C−1 at a volume fraction 0.43. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of acrylic copolymer dispersants bearing epoxy groups on rheological and dielectric properties of carbon black‐filled epoxy system
Authors: Son Bui Thanh , Kook Yoonbong , Lee Eun Sung , Bae Jin‐Young
Published: November 2011

In this article, the use of copolymeric dispersants with an acrylic backbone and epoxy side groups for formulating carbon black (CB)‐epoxy composites are described. Six epoxy‐containing acrylic copolymer dispersants were prepared from hexyl methacrylate (HMA), poly(ethylene glycol) ethyl ether methacrylate (PEGMA), and glycidyl methacrylate via a group transfer polymerization technique. The epoxy‐containing acrylic copolymer of the highest concentration of PEGMA showed a desirable passivation effect on CB, and was found to lower the viscosity of the CB‐epoxy paste, leading to the well‐cured composite after heat treatment. The thick composite film prepared by employing the [CB/acrylic dispersant/epoxy] paste was built up on a Cu plate by a screen printing process followed by thermal curing. The dielectric properties of the 3.1 vol % CB‐filled epoxy film showed us high dielectric constant (Dk 4900) and rather low dissipation factor (Df 29%) at 1 MHz. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Controlled grafting of poly(vinyl acetate) onto starch via RAFT polymerization
Authors: Lu Derong , Xiao Congming , Sun Fei
Published: November 2011

A structure‐exact starch‐based xanthate agent was prepared and used as chain transfer agent to mediate RAFT polymerization of vinyl acetate, which offered a convenient way to well control the structure and composition of starch‐g‐poly(vinyl acetate). The structures of the intermediate and the polymer were verified with FTIR and 1H‐NMR. Gel permeation chromatography measurement results indicated that the polymerization was performed as expected. It was found that the relationship between number average molecular weight and monomer conversion was linear. The polydispersity index of grafted side‐chain ranged from 1.19 to 1.53 and most of them were around 1.2. There was one more degradation stage appeared on the thermogravimetric analysis profile of starch‐g‐poly(vinyl acetate) than that of starch. TEM observation exhibited that the product was able to self‐assemble into micelles in aqueous solution, which suggested the copolymer was amphiphilic. Both the thermal and amphiphilic properties demonstrated the starch‐g‐poly(vinyl acetate) was successfully synthesized as well. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Convenient synthesis of sulfonamides from amines and p‐toluene sulfonyl chloride mediated by crosslinked poly(4‐vinylpyridine)
Authors: Zarchi Mohammad Ali Karimi , Aslani Mariam
Published: November 2011

A general, mild, and convenient method has been developed for the synthesis of various N‐substituted and N, N‐disubstituted sulfonamides, as a class of sulfa drugs, from the corresponding amines and p‐toluene sulfonyl chloride in the presence of readily available crosslinked poly(4‐vinylpyridine) as a catalyst, base or polymeric substrates. The use of polymeric catalyst simplifies routine sulfonylation of amines because it eliminates the traditional purification. The polymer can be removed quantitatively and it can be regenerated and reused for several cycles without losing its activity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The synergistic effect of aluminum hypophosphide and nanosilica on flame‐retarded ethylene–propylene–diene monomer rubber
Authors: Wang Zongtao , Zhang Xian , Bao Chao , Wang Qunyue , Qin Yong , Tian Xingyou
Published: November 2011

The influence of aluminum hypophosphide (AlHPi) and nanosilica on the flame‐retardant and mechanical property of ethylene–propylene–diene monomer (EPDM) rubber was evaluated by limiting oxygen index, and the value of tensile strength and elongation at break. The results show that the introduction of nanosilica into the EPDM/AlHPi blends can not only further improve the flame‐retardant property but also improve the tensile strength and elongation at break significantly, showing a synergistic effect between AlHPi and nanosilica. The flame‐retardant mechanism was further studied by X‐ray diffraction (XRD), thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), and scanning electron microscope (SEM). The results of XRD and TG–DSC indicate that AlHPi will melt along with oxidation at about 337°C, which is helpful to full contact with nanosilica and to enhance the interaction between them; and will further recrystallize above 540°C, which is benefited to enhance the mechanical strength of char layer. The char morphological study by SEM shows that the char layer for the sample with both AlHPi and nanosilica is strong, more uniform and dense, and the scale of the holes in the char layer is smaller compared with the char layer of samples with AlHPi or nanosilica alone. The TG–DSC results show that the sample with both AlHPi and nanosilica has the weakest weight loss rate and heat release rate, compared with the samples with either of them, which is another evidence of the synergistic flame retardant effect between AlHPi and nanosilica. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Mechanical and structural characterizations of simultaneously aligned and heat treated PAN nanofibers
Authors: Ravandi Seyed Abdolkarim Hosseini , Sadrjahani Mehdi
Published: November 2011

A simple and nonconventional electrospinning technique was employed for producing aligned polyacrylonitrile (PAN) nanofibers. A thermal zone was placed between syringe needles and collector in the electrospinning set up to obtain aligned and heat treated nanofibers. Suitable temperatures for heat treat process of PAN nanofibers was determined using differential scanning spectroscopy (DSC) technique. The influence of treatment temperature was investigated on morphology, internal structure and mechanical properties of collected PAN nanofibers. The average fiber diameter measured from SEM images exhibited decreasing trend at higher temperatures. FTIR spectra indicated no considerable difference between chemical structure of untreated and treated PAN nanofibers. Crystallization degree of PAN nanofibers calculated from WAXD patterns showed relatively low change with treatment temperature. Tenacity values of nanofiber bundles increased with increasing temperature while the extension values had an inverse trend. However, the modulus did not show a regular manner, but treated nanofibers had more modulus than untreated ones. The stress and modulus of PAN nanofibers increased to 112.9 MPa and 7.25 GPa at 270°C, respectively. Nanofibers treated at the highest temperature had the largest amount of crystallinity and strength. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Purification and biochemical characterization of glutathione S‐transferases from four field populations of Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)
Authors: Hu Fei , Dou Wei , Wang Jing‐Jing , Jia Fu‐Xian , Wang Jin‐Jun
Published: November 2011

Glutathione S‐transferases (GSTs) are a group of detoxification enzymes that catalyze the nucleophilic addition of glutathione to a wide variety of endogenous and xenobiotic compounds. In this study, GSTs were purified from four field populations of Bactrocera dorsalis with different insecticide susceptibilities by glutathione–agarose affinity chromatography. The populations were collected from Dongguan (DG) and Guangzhou (GZ) of the Guangdong Province, Haikou of the Hainan province (HN), and Kunming of the Yunnan province (YN), China. Differences in GST characteristics among the four populations were studied using purified enzyme samples through comparative SDS‐PAGE, kinetic, and inhibition experiments. The specific activities of the purified enzymes were similar, but the purification yield of the GZ population (31.54%) was the lowest. SDS‐PAGE analysis showed only one band at approximately 23 kDa for these four populations. Kinetic analyses showed that the affinities of the purified GSTs from the GZ and YN populations for 1‐chloro‐2.4‐dinitrobenzene (CDNB) were much higher than those of GSTs from the other two populations, whereas the HN population had the highest catalytic capability in terms of Vmax value. The optimum temperature for CDNB conjugation was 37°C and the optimum pH was 7.5 in all four populations. Inhibition kinetics showed that ethacrynic acid, diethyl maleate, tetraethylthiuram disulfide, curcumin, bromosulfalein, and β‐cypermethrin had excellent inhibitory effects on GSTs in the four populations of B. dorsalis, but the low inhibitory effects of malathion and avermectin did not differ between populations. These results suggest that GSTs may have a role in detoxification of β‐cypermethrin in B. dorsalis. © 2011 Wiley Periodicals, Inc.
Robust H2 Filtering for Discrete‐Time Markovian Jump Linear Systems
Authors: Liu Tao , Zhang Hao , Chen Qijun
Published: November 2011

This paper studies the problems of H2 filtering for discrete‐time Markovian jump linear systems with non‐accessible mode information. The objective is to design a less‐conservative mode‐independent H2 filter such that the filtering error system is stochastically stable. To this end, sufficient conditions for the existence of an upper bound of H2 norm are given in terms of linear matrix inequalities. With the introduction of a slack variable, a less‐conservative filter is derived. The proposed robust H2 filter design method is also applicable to cover the cases where the system matrices are subject to polytopic uncertainty, as well as the case where the transition probability matrix is subject to a given polytopic uncertainty. Application of the proposed method to three examples from the literature demonstrates the favorable performance of the proposed solution to existing approaches.
Robust Performance Controller Synthesis Based on Discrete‐Time Noncausal Linear Periodically Time‐Varying Scaling
Authors: Hosoe Yohei , Hagiwara Tomomichi
Published: November 2011

This paper is concerned with the technique called discrete‐time noncausal linear periodically time‐varying (LPTV) scaling for robust stability analysis and synthesis. It is defined through the lifting treatment of discrete‐time systems, and naturally leads to a sort of noncausal operation of signals. In the robust stability analysis of linear time‐invariant (LTI) systems, it has been shown that even static noncausal LPTV scaling induces some frequency‐dependent scaling when it is interpreted in the context of lifting‐free treatment. This paper first discusses in detail different aspects of the effectiveness of noncausal LPTV scaling, with the aim of showing its effectiveness in controller synthesis. More precisely, we study the robust performance controller synthesis problem, where we allow the controllers to be LPTV. As in the LTI robust performance controller synthesis problem, we tackle our problem with an iterative method without guaranteed convergence to a globally optimal controller. Despite such a design procedure, the closed‐loop H∞ performance is expected to improve as the period of the controller is increased, and we discuss how the frequency‐domain properties of noncausal LPTV scaling could contribute to such improvement. We demonstrate with a numerical example that an effective LPTV controller can be designed for a class of uncertainties for which the well‐known μ‐synthesis fails to derive even a robust stabilization controller.
CFD analysis of two‐phase turbulent flow in internal airlift reactors
Authors: Mohajerani Masroor , Mehrvar Mehrab , Ein‐Mozaffari Farhad
Published: November 2011

The hydrodynamic performance of three internal airlift reactor configurations was studied by the Eulerian–Eulerian k–ε model for a two‐phase turbulent flow. Comparative evaluation of different drag and lift force coefficient models in terms of liquid velocity in the riser and downcomer and gas holdup in the riser was highlighted. Drag correlations as a function of Eötvös number performed better results in comparison to the drag expressions related to Reynolds number. However, the drag correlation as a function of both Reynolds and Eötvös numbers fitted well with experimental results for the riser gas holdup and downcomer liquid velocity in configurations I and II. Positive lift coefficients increase the liquid velocity and decrease the riser gas holdup, while opposite results were obtained for negative values. By studying the effects of bubble size and their shape, the smaller bubbles provide a lower liquid velocity and a gas holdup. The effects of bubble‐induced turbulence and other non‐drag closure models such as turbulent dispersion and added mass forces were analysed. The gas velocity and gas holdup distributions, liquid velocity in the riser and downcomer, vectors of velocity magnitude and streamlines for liquid phase, the dynamics of gas holdup distribution and turbulent viscosity at different superficial gas velocities for different reactor configurations were computed. The effects of various geometrical parameters such as the draft tube clearance and the ratio of the riser to the downcomer cross‐sectional area on liquid velocities in the riser and the downcomer, the gas velocity and the gas holdup were explored. © 2011 Canadian Society for Chemical Engineering
Comparative kinetics of transesterification for biodiesel production from palm oil and mustard oil
Authors: Issariyakul Titipong , Dalai Ajay K.
Published: November 2011

The kinetics of palm oil and mustard oil transesterification are compared. Transesterification of palm oil and mustard oil using KOH as a catalyst was performed at various reaction temperatures ranging from 40 to 60°C. The reaction steps are reversible and transesterification is favoured at elevated temperatures. The reaction step of triglyceride to diglyceride is the rate determining step (RDS) that controls kinetics of overall transesterification with activation energies of 30.2 and 26.8 kJ/mol for palm oil and mustard oil transesterification, respectively. It is found that percentage of saturated compounds play a vital role on transesterification kinetics. © 2011 Canadian Society for Chemical Engineering
Multicomponent mass diffusion in porous pellets: Effects of flux models on the pellet level and impacts on the reactor level. Application to methanol synthesis
Authors: Solsvik Jannike , Jakobsen Hugo A.
Published: November 2011

A heterogeneous model has been derived for a fixed packed‐bed reactor producing methanol. Several closures for the intra‐particle mass diffusion fluxes; Maxwell–Stefan, Wilke, dusty gas and Wilke–Bosanquet, have been compared on the level of the catalyst pellet and the impacts of the different particle flux closures on the reactor performance are investigated. A preparatory study of the transport phenomena on the pellet level is recommended prior to any large‐scale reactor simulation to determine what are the rate determining transport mechanisms. Hence, if Knudsen diffusion is apparent on the level of the pellet, a combined bulk and Knudsen diffusion model should naturally be used in the reactor simulations as well, because Knudsen diffusion can influence significantly on the reactor conversion. Minor differences are observed between the diffusion flux models on both pellet and reactor level. Hence, for the reactor operation conditions applied in this study, the Wilke model is a good approximation to the rigorous Maxwell–Stefan model, and similarly, the Wilke–Bosanquet model is an appropriate model to use in replacement for the dusty gas model. Moreover, variable pressure and viscous flow can be neglected in the pellet model, as the effect of these contributions are not visible at neither pellet or reactor level. © 2011 Canadian Society for Chemical Engineering
Triorganyl‐ and Diorganyloxozirconium Hydridoborates – Synthesis and Structures
Authors: Knizek Jörg , Nöth Heinrich , Schmidt‐Amelunxen Martin
Published: November 2011

The reactions of Zr(OBu)4 and Zr(OEt)4 with H3B·THF in THF led to HB(OR)2 and B(OR)3, but no zirconium tetrahydroborate [(RO)4–nZr(BH4)n] could be isolated. On the contrary, the reactions of [tBu3CO]4–nZrCln and [tBu3SiO]4–nZrCln with LiBH4 generated the tetrahydroborates [(RO)3Zr(BH4)] and [(RO)2Zr(BH4)2]. These can be used to produce by hydroborate exchange dihydridodiorganyl borates [(RO)4–nZr(H2BC8H14)n] and byproducts. The structures of the new zirconium hydridoborates have been determined by X‐ray crystallography. Compound [(tBu3CO)3Zr(H2BC8H14)] shows site‐disordered dihydroborate units with agostic Zr–H–C interactions, while [(tBu3SiO)2Zr(H2BC8H14)2] is quite symmetric (C2/c). The corresponding tetrahydridoborates possess in most cases μ31‐bonded ZrH3BH groups.
Exploitation of detergent thermodynamics in the direct solubilization of myelin membrane proteins for two‐dimensional gel electrophoresis for proteomic analysis
Authors: Nair Sreepriya , Xavier Tessy , Satheesh Kumar Madathiparambil Kumaran , Saha Sharmistha , Menon Krishnakumar N.
Published: November 2011

Performing 2‐DE of lipid‐rich multilamellar membranes like myelin is a cumbersome task. However, for understanding its molecular organization and changes during diseases, identification of proteins of myelin is essential. Although the 2‐D‐proteomic approach of myelin has been employed to understand the myelin proteome, representation of myelin proteins in its entirety is still a challenge. 2‐DE profiling of myelin proteins is very important for the detection of immuno‐reactivity to myelin proteins from various biological fluids following Western blotting in diseases like multiple sclerosis. Here we developed a novel approach by exploiting the thermodynamic principles behind detergent‐mediated solubilization of myelin membranes without any conventional processing of myelin involving precipitation of myelin proteins. We show that the addition of myelin to ASB‐14‐4 resulted in significant increase in protein representation of myelin in 2‐DE compared with the addition of ASB‐14‐4 to myelin. Moreover, the number and resolution of spots are significantly higher in myelin to ASB‐14‐4 strategy than other strategies of myelin sample processing such as ASB‐14‐4 to myelin or ethanol or acetone or methanol–ammonium acetate precipitation of myelin proteins. In addition, the step involves no precipitation that selective removal of any proteins as a result of precipitation is nil and a qualitative representation of myelin proteins in a 2‐D gel is achieved.
Online enzymatic sequencing of glycans from Trastuzumab by phospholipid‐assisted capillary electrophoresis
Authors: Archer‐Hartmann Stephanie A. , Crihfield Cassandra L. , Holland Lisa A.
Published: November 2011

CE separations of glycans taken from the cancer drug, Trastuzumab (Herceptin®), were accomplished using phospholipid additives. Glycans were labeled with 1‐aminopyrene‐3,6,8‐trisulfonic acid and were separated with efficiencies as high as 510 000 theoretical plates in a 60.2 cm 25 μm id fused‐silica capillary. The thermally tunable phospholipid was loaded into the capillary when it possessed a viscosity similar to that of water. The temperature was increased, and the separations were performed when the material exhibited higher viscosity. Enzymes were integrated into the separation with the phospholipid additive. Neuraminidase, β1‐4 galactosidase, and β‐N‐acetylglucosaminidase were injected into the capillary without covalent modification and used for enzyme hydrolysis. Exoglycosidase enzymes cleaved the terminal glycan residues. The glycan sequence could be verified based on enzyme specificity. Neuraminidase was used to determine total glycan content of the low‐abundance glycans containing sialic acid. β1‐4 Galactosidase and β‐N‐acetylglucosaminidase were used sequentially in‐capillary, to determine the structure of the high‐abundance glycans.
Inverse correlation between clinical response to paroxetine and plasma drug concentration in patients with major depressive disorders
Authors: Yasui‐Furukori Norio , Nakagami Taku , Kaneda Ayako , Inoue Yoshimasa , Suzuki Akihito , Otani Koichi , Kaneko Sunao
Published: November 2011

Objective

There are few data concerning a clear relationship between the clinical effect of paroxetine and plasma drug concentrations, although therapeutic ranges have been established for some tricyclic antidepressants.

Methods

In this study, 120 patients with major depressive disorders were treated with 10–40 mg/day of paroxetine for 6 weeks, and a total of 89 patients completed the protocol. A clinical evaluation using the Montgomery‐Asberg Depression Rating Scale (MADRS) was performed at 0, 1, 2, 4 and 6 weeks.

Results

Significant correlations were found between the plasma concentrations of paroxetine and the percentage improvement in the total MADRS scores (r = −0.282, p < 0.01) and the final MADRS scores at 6 weeks (r = 0.268, p < 0.05). The conventional receiver‐operating‐characteristic curve showed the fraction of true positive results and false negative results for various cut‐off levels of paroxetine concentration for response and remission. The thresholds for both response and remission that gave the maximal sensitivity and specificity for paroxetine concentrations were 64.2 ng/ml.

Conclusions

These results suggest that plasma paroxetine concentrations are negatively associated with improvement and that response occurs at the upper threshold of 64.2 ng/ml of paroxetine. These findings should be replicated with a larger patient sample. Copyright © 2011 John Wiley & Sons, Ltd.
Cellular proliferation, cellular viability, and biocompatibility of HA‐ZnO composites
Authors: Saha Naresh , Dubey Ashutosh K. , Basu Bikramjit
Published: November 2011

One of the important issues in the development of hydroxyapatite (HA)‐based biomaterials is the prosthetic infection, which limits wider use of monolithic HA despite superior cellular response. Recently, we reported that ZnO addition to HA can induce bactericidal property. It is therefore important to assess how ZnO addition influences the cytotoxicity property and cell adhesion/proliferation on HA‐ZnO composite surfaces in vitro. In the above perspective, the objective of this study is to investigate the cell type and material composition dependent cellular proliferation and viability of pressureless sintered HA‐ZnO composites. The combination of cell viability data as well as morphological observations of cultured human osteoblast‐like SaOS2 cells and mouse fibroblast L929 cells suggests that HA‐ZnO composites containing 10 Wt % or lower ZnO exhibit the ability to support cell adhesion and proliferation. Both SaOS2 and L929 cells exhibit extensive multidirectional network of actin cytoskeleton and cell flattening on the lower ZnO containing (≤10 Wt %) HA‐ZnO composites. The in vitro results illustrate how variation in ZnO content can influence significantly the cell vitality, as evaluated using MTT biochemical assay. Also, the critical statistical analysis reveals that ZnO addition needs to be carefully tailored to ensure good in vitro cytocompatibility. The underlying reasons for difference in biological properties are analyzed. It is suggested that surface wettability as well as dissolution of ZnO, both contribute to the observed differences in cellular viability and proliferation. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
A computational chemist approach to gas sensors: Modeling the response of SnO2 to CO, O2, and H2O Gases
Authors: Ducéré Jean‐Marie , Hemeryck Anne , Estève Alain , Rouhani Mehdi Djafari , Landa Georges , Ménini Philippe , Tropis Cyril , Maisonnat André , Fau Pierre , Chaudret Bruno
Published: November 2011

A general bottom‐up modeling strategy for gas sensor response to CO, O2, H2O, and related mixtures exposure is demonstrated. In a first stage, we present first principles calculations that aimed at giving an unprecedented review of basic chemical mechanisms taking place at the sensor surface. Then, simulations of an operating gas sensor are performed via a mesoscopic model derived from calculated density functional theory data into a set of differential equations. Significant presence of catalytic oxidation reaction is highlighted. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2012
Iatrogenic arteriovenous fistula in the Arm in an infant: Diagnostic and therapeutic considerations
Authors: Kotagal Meera , Reiss Aya , Vo Nghia , Feldman Kenneth , Drugas George , Avansino Jeffrey R.
Published: November 2011

Iatrogenic arteriovenous fistulas (AVF) are well described in adults; however, this complication is rarely described and reported in infants. We report the case of a 3‐month‐old infant with complicated gastroschisis requiring multiple venipunctures who presented with signs and symptoms suggestive of traumatic arteriovenous fistula. Ultrasound imaging confirmed the presence of a wide‐necked AVF between the brachial artery and vein. The fistula was surgically repaired. This case report describes the clinical imaging and treatment options for infants with iatrogenic AVF. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound, 2012
Heterothermy in two mole‐rat species subjected to interacting thermoregulatory challenges
Authors: Boyles Justin G. , Verburgt Luke , McKechnie Andrew E. , Bennett Nigel C.
Published: November 2011

Maintaining a high and constant body temperature (Tb) is often viewed as a fundamental benefit of endothermy, but variation inTbis likely the norm rather than an exception among endotherms. Thus, attempts to elucidate which factors causeTbof endotherms to deviate away from theTbthat maximizes performance are becoming more common. One approach relies on an adaptive framework of thermoregulation, used for a long time to predict variation inTbof ectotherms, as a starting point to make predictions about the factors that should lead to thermoregulatory variation in endotherms. Here we test the predictions that when confronted with thermoregulatory challenges endotherms should (1) become more heterothermic, (2) lower theirTbsetpoint, and/or (3) increase behavioral thermoregulation (e.g., activity levels or social thermoregulation). We exposed two species of relatively homeothermic mole‐rats to two such challenges: (a) ambient temperatures (Ta) well below the thermoneutral zone and (b) increased heat loss caused by the removal of dorsal fur. In general, our results support the adaptive framework of endothermic thermoregulation with each species conforming to some of the predictions. For example, Mashona mole‐rats (Fukomys darlingi) increased heterothermy asTadecreased, highveld mole‐rats (Cryptomys hottentotus pretoriae) displayed lowerTb's after shaving, and both species increased behavioral thermoregulation asTadecreased. This suggests that there is some merit in extending the adaptive framework to endotherms. However, none of the three predictions we tested was supported under all experimental conditions, reiterating that attempts to determine universal factors causing variation inTbof endotherms may prove challenging.J. Exp. Zool. 317:73–82, 2012. © 2011 Wiley Periodicals, Inc.
Polycyclic N‐Heterocyclic Compounds, Part 69: Synthesis of 5‐amino‐1,2‐dihydro[1]benzofuro[3,2‐d]furo[2,3‐b]pyridines and their transformations to related compounds
Authors: Okuda Kensuke , Takano Jun‐ichi , Hirota Takashi , Sasaki Kenji
Published: November 2011

Reaction of 3‐(3‐cyanopropoxy)[1]benzofuran‐2‐carbonitriles with potassium tert‐butoxide gave 5‐amino‐1,2‐dihydro[1]benzofuro[3,2‐d]furo[2,3‐b]pyridines and 5‐amino‐2,3‐dihydro[1]benzofuro[3,2‐b]oxepin‐4‐carbonitriles as new ring systems. Reactions of the 5‐chloro derivative, obtained from 5‐amino‐1,2‐dihydro[1]benzofuro[3,2‐d]furo[2,3‐b]pyridine, produced a dihydrofuran ring‐opened compound and 5‐substituted compounds. J. Heterocyclic Chem.,(2011).
2‐amino‐X‐nitrobenzimidazoles as precursors of food‐borne carcinogens: A new approach to IQ synthesis
Authors: Bella Maroš , Milata Viktor , Larina Lyudmila I.
Published: November 2011

Cyclization of (non)‐methylated nitro‐o‐phenylenediamines with cyanogen bromide provided nitro‐substituted 2‐aminobenzimidazoles in good up to excellent yields. Catalytic hydrogenation of 2‐amino‐1‐methyl‐5‐nitrobenzimidazole yielded 2,5‐diamino‐1‐methylbenzimidazole, which on treatment with 1,1,3,3‐tetramethoxypropane in methanol and subsequently after removal of methanol in polyphosphoric acid afforded food‐borne carcinogen 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ) in 20% yield. J. Heterocyclic Chem.,(2011).
Modelling monthly diffuse solar radiation fraction and its validity over the Indian sub‐tropics
Authors: Singh Jyotsna , Bhattacharya Bimal K. , Kumar Manoj , Mallick Kaniska
Published: November 2011

A three‐parameter sigmoidal ‘local’ model (climate‐specific) and a ‘regional’ model (common for all climates) have been developed for measuring the monthly average diffuse solar radiation fraction from atmospheric transmissivity by using large, 21‐year datasets (1973–1993) over four stations (Jodhpur, New Delhi, Nagpur and Kolkata). These stations represent the four ‘prime’ climates (arid, semi‐arid, sub‐humid and humid) over the Indian sub‐tropics. The models have been validated with the longer time‐series (10 years) of independent datasets (1994–2003) of 4 ‘prime’ climates as well as datasets from 16 stations using one‐year datasets (termed as secondary stations) of the Indian region. The monthly diffuse fraction estimates were also compared with seven globally existing models. The ‘regional’ model showed more accurate estimates than ‘local’ models over three (semi‐arid, sub‐humid and humid) of the four ‘prime’ climates. However, the different error statistics showed that the ‘regional’ model outperformed the globally existing models which failed to capture diffuse fraction variability over the Indian sub‐tropics. The extendibility of the ‘regional’ model over ‘secondary’ stations in India showed an overall good performance withR2: 0.78–0.96 andRMSE: 0.017–0.125, except for two stations. These models are unique for Indian sub‐tropics and can undoubtedly be used for predicting future diffuse solar radiation fraction from transmissivity datasets of climate simulations, and also for other meteorological, climatological, solar energy‐based applications. Copyright © 2011 Royal Meteorological Society