bluuebunny/crossref_metadata_2025 huggingface dataset:
Real‐time dynamic hoist scheduling for multistage material handling process under uncertainties
Authors: Zhao Chuanyu , Fu Jie , Xu Qiang
Published: May 2012

Multistage material handling processes are broadly used for manufacturing various products/jobs, where hoists are commonly used to transport inline products according to their processing recipes. When multiple types of jobs with different recipes are simultaneously and continuously handled in a production line, the hoist movement scheduling should be thoroughly investigated to ensure the operational feasibility of every job inline and in the meantime to maximize the productivity if possible. The hoist scheduling will be more complicated, if uncertainties of new coming jobs are considered, that is, the arrival time, type, recipe, and number of new jobs are totally unknown and unpredictable before they join the production line. To process the multiple jobs already inline and the newly added jobs, the hoist movements must be swiftly rescheduled and precisely implemented whenever new job(s) come. Because a reschedule has to be obtained online without violating processing time constraints for each job, the solution identification time for rescheduling must be taken into account by the new schedule itself. All these stringent requisites motivate the development of real‐time dynamic hoist scheduling (RDHS) targeting online generation of reschedules for productivity maximization under uncertainties. Hitherto, no systematic and rigorous methodologies have been reported for this study. In this article, a novel RDHS methodology has been developed, which takes into account uncertainties of new coming jobs and targets real‐time scheduling optimality and applicability. It generally includes a reinitialization algorithm to accomplish the seamless connection between the previous scheduling and rescheduling operations, and a mixed‐integer linear programming model to obtain the optimal hoist reschedule. The RDHS methodology addresses all the major scheduling issues of multistage material handling processes, such as multiple recipes, multiple jobs, multicapacity processing units, diverse processing time requirements, and even optimal processing queue for new coming jobs. The efficacy of the developed methodology is demonstrated through various case studies. © 2012 American Institute of Chemical Engineers AIChE J, 59: 465–482, 2013
Multiscale modeling of the effects of unlimited four‐membered ring formation on sol‐gel silica film molecular structure
Authors: Li Xin , Rankin Stephen E.
Published: May 2012

A modified multiscale model of a sol‐gel silica drying process is presented that treats first‐shell substitution effects and unlimited four‐membered ring cyclization. The inclusion of four‐membered (8‐atom) rings allows the model to simulate the formation of the tetrasiloxane rings and cubic silsesquioxane cages known to be prevalent components of sol‐gel silica systems, as well as a full range of other ring‐containing structures. The polymerization process is treated using a dynamic Monte Carlo method where a discrete population of one million monomers evolves according to kinetic rules, including unimolecular‐like closure of three‐bond blocks. Compared with prior simulations with extensive cyclization that allowed only three‐membered rings, the molecular structures formed with unlimited four‐membered ring are more complex, and the occurrence of “skinning” (the rapid formation of a gel only at the surface of the film) is more pronounced and leads to more severe structure gradients. © 2012 American Institute of Chemical Engineers AIChE J, 59: 707–718, 2013
Output feedback control of dissipative PDE systems with partial sensor information based on adaptive model reduction
Authors: Pitchaiah Sivakumar , Armaou Antonios
Published: May 2012

We address the problem of control of spatially distributed processes in the presence of measurement constraints. Specifically, we assume the availability of sensors that measure part of the state spatial profile. The measurements are utilized for the derivation and on‐demand update of reduced order models (ROM) based on an extension of the adaptive proper orthogonal decomposition (APOD) method using a snapshot reconstruction technique. The proposed Gappy‐APOD methodology constructs locally accurate low‐dimensional ROM thus resulting in a computationally efficient alternative to using a large‐dimensional ROM with global validity. Based on the low‐dimensional ROM and continuous measurements available from point sensors a Lyapunov‐based static output feedback controller is subsequently designed. The proposed controller design method is illustrated on an unstable process modeled by the Kuramoto‐Sivashinsky equation, when the designed controller successfully stabilizes the process even in the presence of model uncertainty. © 2012 American Institute of Chemical Engineers AIChE J, 59: 747–760, 2013
The best objective function for seeded batch crystallization
Authors: Hsu Che‐Wei , Ward Jeffrey D.
Published: May 2012

Although many researchers have optimized the operation of seeded batch crystallization, there remains little understanding of the effect of the choice of objective function on the optimization and no consensus on which objective function is best. In this work, different objective functions for seeded batch crystallization are compared by calculating the supersaturation trajectory that minimizes each objective function and then comparing the results of each trajectory. We show that some objective functions lead to trajectories that cause excessive nucleated mass and should be avoided. We conclude that the best objective function in most cases is to minimize the nucleated mass. This also corresponds to maximizing the growth of seeds, and leads to a product with a large volume mean size. We also show that the width of the product crystal size distribution can be controlled much more effectively by manipulating seed properties than by adjusting the supersaturation trajectory. © 2012 American Institute of Chemical Engineers AIChE J, 59: 390–398, 2013
Fatigue and static performances of butterfly joints under hygrothermal exposure conditions
Authors: Altan Gürkan , Topçu Muzaffer
Published: May 2012

In this study, the static and dynamic behaviors under different environmental conditions of mechanical insert butt joints with butterfly joint locks that could be used instead of adhesively bonded butt joints in composite plate joints were investigated. The experimental specimens and butterfly‐shaped joining components with the same material configuration were cut from a [(0/90)8]s laminated composite plate with a water jet in harmony with the geometric parameters. The fatigue experiments were carried out at a constant load ratio of 0.1 and at different maximum fatigue loads. To compare the joints with each other, the experiments were conducted under a 10‐Hz fatigue frequency and under a tension–tension load with constant amplitude of a sinus curve shape. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Oxidation of styrene over polymer‐ and nonpolymer‐anchored Cu(II) and Mn(II) complex catalysts
Authors: Sharma Sweta , Sinha Shishir , Biswas Prakash , Maurya Mannar R. , Chand Shri
Published: May 2012

Catalytic oxidation of styrene was investigated over polymer‐ and nonpolymer‐anchored Cu(II) and Mn(II) complex catalysts prepared by schiff base tridentate ligands. The effect of temperature, styrene to H2O2 mole ratio and catalyst amount on the catalytic activity and product selectivity was investigated. Further, the catalysts were characterized by various techniques, such as elemental analysis, atomic absorption spectroscopy (AAS), FTIR, FE‐SEM, EDAX, TGA, and UV–vis spectrophotometer. The elemental analysis, EDAX and AAS results confirmed the formation of Cu(II) and Mn(II) complexes, and it was found that the metal loading in the polymer‐anchored complex catalysts were in the range of 0.53–3.74 %. FTIR results showed the co‐ordination bond formation between the polymer ligands and metal ion. The catalytic data showed that, over all the catalysts, the main reaction products were benzaldehyde, styrene oxide, and benzoic acid. The polymer‐anchored complex catalysts were found to be much more active when compared with nonpolymer‐anchored catalysts. The maximum conversion of styrene (92.3%) was obtained over PS‐[Cu(Hfsal‐aepy)Cl] catalyst with benzaldehyde selectivity to 69% at the styrene to H2O2 mole ratio of 1 : 4 at 75°C. Although the PS‐[Mn(Hfsal‐aepy)Cl] catalyst was less active, it was highly selective to benzaldehyde. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The effect of wool surface and interior modification on subsequent photostability
Authors: Zhang Hu , Deb‐Choudhury Santanu , Plowman Jeffrey , Dyer Jolon
Published: May 2012

Wool surface and interior modification can impart favorable properties, such as felting/shrink resistance, settability, or improved affinity for dyes. However, in principle such modification may have an either beneficial or adverse effect on the subsequent photostability of the modified wool. In this study, a range of representative physical and chemical modification approaches including the use of helium gas plasma, papain, acylation with acid anhydride, and permanganate oxidation were applied to wool fabrics, and the subsequent effects characterized using scanning electron microscopy, FTIR‐ATR, contact angle goniometry, fluorescence spectrophotometry, and tensile strength test. The relative photostability of control and treated wool were evaluated in terms of coloration changes under UVA, UVB, and blue light irradiation. We have shown that the subsequent photostability of modified wool fabrics is highly dependent on the modification type, and this factor should be carefully considered in the design and application of wool treatments. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Prediction of mechanical properties of poly(ethylene terephthalate) using infrared spectroscopy and multivariate calibration
Authors: Caetano Viviane Fonseca , Vinhas Glória Maria , Pimentel Maria Fernanda , Simões Simone da Silva , de Araújo Mário César Ugulino
Published: May 2012

This work describes a method to determine mechanical properties (tensile strength at break and tensile modulus) of poly(ethylene terephthalate) using median infrared spectroscopy and multivariate calibration. Infrared spectroscopy is very promising for polymer process control and final product analysis because it is rapid and nondestructive. The spectra of the films were obtained using two techniques: attenuated total reflection and direct transmission. The spectra were subjected to various preprocessing procedures, such as smoothing and derivative using the algorithm Savitzy‐Golay, standard normal variate, multiplicative scatter correction and, as well, combinations of some of these preprocessing techniques. The predictive ability of the regression models were evaluated using an external validation set. The regression techniques used, partial least square and multiple linear regression, showed, in general, comparable results with root mean square error of prediction similar to the repeatability of the conventional method used to determine these mechanical properties (1.3 kgf/mm2 for tensile strength at break and 29.6 kgf/mm2 for tensile modulus). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The effect of primary structural parameters of poly(methacrylic acid) xerogels on the kinetics of swelling
Authors: Jovanovic Jelena , Adnadjevic Borivoj
Published: May 2012

Xerogels of poly(methacrylic acid) (MAXG) with different primary structural parameters (PSP) [number average molar mass between the network crosslinks (Mc), the crosslink degree (ρc), and the distance between the macromolecular chains (d)] are successfully synthesized by crosslinking free‐radical polymerization. The isothermal swelling curves of synthesized MAXG are measured in distilled water in the temperature range of 25–40°C. The swelling conversion curves of all the MAXG may be described with kinetics model of phase boundary controlled reaction, i.e., contracting area (R2). The values of swelling kinetics parameters (Ea and lnA) linearly increase with the increase in Mc. This work presented a novel and quantum model of the mechanism of xerogel's swelling activation process based on resonant coupling of vibration oscillation of water molecules and vibration modes of xerogel. A quantum nature of Ea of swelling process is proved and explained the effects of PSP on the values of swelling kinetics parameters. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis of nanosized ethylene–propylene rubber latex via polyisoprene hydrogenation
Authors: Kongsinlark Anong , Rempel Garry L. , Prasassarakich Pattarapan
Published: May 2012

Nanosized ethylene–propylene rubber (EPM) latex with a particle size of 47 nm was synthesized via an alternative route consisting of isoprene (IP) polymerization followed by hydrogenation. First, the IP monomer was polymerized by differential microemulsion polymerization to obtain polyisoprene (PIP) rubber latex with a particle size of 42 nm. The structure of synthetic PIP was hydrogenated at the carbon–carbon double bonds to produce an ethylene–propylene copolymer by diimide reduction in the presence of hydrazine and hydrogen peroxide using boric acid as promotor. The degree of hydrogenation was determined by proton nuclear magnetic resonance (1H‐NMR) spectroscopy and the structure of the ethylene–propylene copolymer was identified by 13C‐NMR spectroscopy. In nanosized PIP hydrogenation, the hydrogenation level was found to be increased by boric acid addition. An EPM yield of 94% was achieved using a hydrogen peroxide : hydrazine ratio of 1.5 : 1. The EPM produced from PIP has high thermal stability with the maximum decomposition temperature of 510°C and a glass transition temperature of ‐42.4°C close to commercial ethylene–propylene diene rubber. Dynamic mechanical analysis indicated that EPM had a maximum storage modulus due to the saturated carbons domains of the ethylene segments in the polymer chains. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Microcapsules prepared from a polycondensate‐based cement dispersant via layer‐by‐layer self‐assembly on melamine‐formaldehyde core templates
Authors: Pavlitschek Thomas , Gretz Markus , Plank Johann
Published: May 2012

Novel microcapsules were prepared from colloidal core–shell particles by acid dissolution of the organic core. Weakly crosslinked, monodisperse and spherical melamine‐formaldehyde polycondensate particles (diameter ∼ 1 μm) were synthesized as core template and coated with multilayers of an anionic polyelectrolyte via layer‐by‐layer deposition technique. As polyelectrolytes, an anionic naphthalenesulfonate formaldehyde polycondensate that is a common concrete superplasticizer and thus industrially available, and cationic poly(allylamine hydrochloride) were used. Core removal was achieved by soaking the core–shell particles in aqueous hydrochloric acid at pH 1.6, resulting in hollow microcapsules consisting of the polyelectrolytes. Characterization of the template, the core–shell particles, and the microcapsules plus tracking of the layer‐by‐layer polyelectrolyte deposition was performed by means of zeta potential measurement and scanning electron microscopy. The microcapsules might be useful as microcontainers for cement additives. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Photodegradation of poly(ethyleneoxide)/montmorillonite composite films
Authors: Lombardo Patrícia C. , Poli Alessandra L. , Neumann Miguel G. , Machado Douglas S. , Schmitt Carla C.
Published: May 2012

Poly(ethyleneoxide) (PEO) composites with SWy‐1 montmorillonite were prepared by mixing the polymer and the clay in aqueous colloidal solutions. Thin films of the composites were obtained by solvent evaporation and exposed to 254‐nm UV‐irradiation. The photodegradation was monitored by FTIR and the chain scission reaction was confirmed by measurement of average molecular weights using size exclusion chromatography. The rate of oxidation of pure PEO was much faster than that of the composites (SWy‐1/PEO). The SWy‐1 clay stabilizes the polymer against UV irradiation. This stabilization is due to two factors: on one side, the absorption of UV radiation by the clay, and on the other the scattering of the incident radiation by the particles; both contributing to minimize the degradation rate of the PEO present in the composites. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Optoelectronic Properties of Dicyanofluorene‐Based n‐Type Polymers
Authors: Vijayakumar Chakkooth , Saeki Akinori , Seki Shu
Published: May 2012

Three new donor–acceptor‐type copolymers (P1, P2, P3) consisting of dicyanofluorene as acceptor and various donor moieties were designed and synthesized. Optoelectronic properties were studied in detail by means of UV‐visible absorption and fluorescence spectroscopy, cyclic voltammetry, space‐charge‐limited current (SCLC), flash‐photolysis time‐resolved microwave conductivity (FP‐TRMC), and density functional theory (DFT). All polymers showed strong absorption in the UV‐visible region and the absorption maximum undergoes redshift with an increasing number of thiophene units in the polymer backbone. SCLC analysis showed that the electron mobilities of the polymers in the bulk state were 1 to 2 orders higher than that of the corresponding hole mobilities, which indicated the n‐type nature of the materials. By using FP‐TRMC, the intrapolymer charge‐carrier mobility was assessed and compared with the interpolymer mobility obtained by SCLC. The polymers exhibited good electron‐accepting properties sufficiently high enough to oxidize the excited states of regioregular poly(3‐hexylthiophene) (P3HT (donor)), as evident from the FP‐TRMC analysis. The P3 polymer exhibited the highest FP‐TRMC transients in the pristine form as well as when blended with P3HT. Use of these polymers as n‐type materials in all‐polymer organic solar cells was also explored in combination with P3HT. In accordance with the TRMC results, P3 exhibited superior electron‐transport and photovoltaic properties to the other two polymers, which is explained by the distribution of the energy levels of the polymers by using DFT calculations.
Systematic review of haemorrhage and rupture of hepatocellular adenomas
Authors: van Aalten S M , de Man R A , IJzermans J N M , Terkivatan T
Published: May 2012

Background

Although benign in itself, hepatocellular adenoma (HCA) can be complicated by hormone-induced growth, and subsequent haemorrhage and rupture. The exact risk of haemorrhage and rupture is not known. This systematic review of the literature was carried out with the aim of estimating the risk of haemorrhage and rupture in HCA.

Methods

A systematic literature search of the PubMed and Embase databases was performed for all articles relevant to haemorrhage and/or rupture of HCA, published between 1969 and March 2011.

Results

Twenty-eight articles met the selection criteria, containing a total of 1176 patients. Haemorrhage was reported with an overall frequency of 27·2 per cent among patients, and in 15·8 per cent of all HCA lesions. Rupture and intraperitoneal bleeding were reported in 17·5 per cent of patients. Bleeding was the first symptom in 68·5 per cent of patients with a bleeding HCA. Six of 13 articles reporting the size of HCA lesions in which bleeding occurred mentioned haemorrhage in HCAs smaller than 5 cm.

Conclusion

Haemorrhage and rupture are common in patients with HCA.
Hypothalamic expression ofPeg3gene is associated with maternal care differences between SM/J and LG/J mouse strains
Authors: Chiavegatto Silvana , Sauce Bruno , Ambar Guilherme , Cheverud James M. , Peripato Andrea C.
Published: May 2012

Maternal care is essential in mammals, and variations in the environment provided by mothers may directly influence the viability of newborns and emotional behavior later in life. A previous study investigated genetic variations associated with maternal care in an intercross of LG/J and SM/J inbred mouse strains and identified two single‐locus QTLs (quantitative trait loci). Here, we selected three candidate genes located within these QTLs intervals;Oxton chromosome 2, andFosBandPeg3on chromosome 7 and tested their association with maternal care. LG/J females showed impaired postpartum nest building and pup retrieval, a one‐day delay in milk ejection, reduced exploratory activity, and higher anxiety‐like behavior when compared to SM/J females. The nucleotide sequences ofOxtandFosBwere similar between strains, as were their hypothalamic expression levels. Conversely,Peg3nucleotide sequences showed four nonsynonymous replacement substitutions on LG/J dams, T11062G, G13744A, A13808G, and G13813A, and a 30 base pair (10 aa) in tandem repeat in the coding region with three copies in SM/J and five copies in LG/J. Maternal care impaired LG/J mothers express 37% lowerPeg3mRNA levels in the hypothalamus on the second postpartum day. We also found an association of the Peg3 repeat‐variant and poor maternal care in F2heterozygote females derived from a LG/J × SM/J intercross. These results may suggest that the maternally imprintedPeg3gene is responsible for the single‐locus QTL on chromosome 7 that has been shown to influence maternal care in these strains. Furthermore, these data provide additional support for an epigenetic regulation of maternal behavior.
Use of cranial CT to identify a new infarct in patients with a transient ischemic attack
Authors: Al‐Khaled Mohamed , Matthis Christine , Münte Thomas F. , Eggers Jürgen
Published: May 2012

Research on infarct detection by noncontrast cranial computed tomography (CCT) in patients with transient ischemic attack (TIA) is sparse. However, the aims of this study are to determine the frequency of new infarcts in patients with TIA, to evaluate the independent predictors of infarct detection, and to investigate the association between a new infarct and early short‐term risk of stroke during hospitalization. We prospectively evaluated 1533 consecutive patients (mean age, 75.3 ± 11 years; 54% female; mean National Institutes of Health Stroke Scale [NIHSS] score, 1.7 ± 2.9) with TIA who were admitted to hospital within 48 h of symptom onset. A new infarct was detected by CCT in 47 (3.1%) of the 1533 patients. During hospitalization, 17 patients suffered a stroke. Multivariate logistic regression analysis revealed the following independent predictors for infarct detection: NIHSS score ≥10 (odds ratio [OR], 4.8), time to CCT assessment >6 h (OR 2.2), and diabetes (OR 2.3). The evidence of a new infarct was not associated with the risk of stroke after TIA. The frequency of a new infarct in patients with TIA using CCT is low. The use of the CCT tool to predict the stroke risk during hospitalization in patients with TIA is found to be inappropriate. The estimated clinical predictors are easy to use and may help clinicians in the TIA work up.
The Complex of Cytochrome f and Plastocyanin from Nostoc sp. PCC 7119 is Highly Dynamic
Authors: Scanu Sandra , Förster Johannes , Finiguerra Michela G. , Shabestari Maryam Hashemi , Huber Martina , Ubbink Marcellus
Published: May 2012

Cytochrome f (Cyt f) and plastocyanin (Pc) form a highly transient complex as part of the photosynthetic redox chain. The complex from Nostoc sp. PCC 7119 was studied by NMR relaxation spectroscopy with the aim of determining the orientation of Pc relative to Cyt f. Chemical‐shift‐perturbation analysis showed that the presence of spin labels on the surface of Cyt f does not significantly affect the binding of Pc. The paramagnetic relaxation enhancement results are not consistent with a single orientation of Pc, thus indicating that multiple orientations must occur and suggesting that an encounter state represents a large fraction of the complex.
Catalytic NO Oxidation Pathways and Redox Cycles on Dispersed Oxides of Rhodium and Cobalt
Authors: Weiss Brian M. , Artioli Nancy , Iglesia Enrique
Published: May 2012

The elementary steps and site requirements for the oxidation of NO on Rh and Co and the oxidation state of the catalysts were probed by isotopic tracers, chemisorption methods, and kinetic measurements of the effects of the pressures of NO, O2, and NO2 on turnover rates. On both catalysts, NO oxidation rates were first order in NO and O2 and were inversely proportional to NO2 pressure, as observed on Pt and PdO. These data implied that O2 activation on an isolated vacancy (*) on the catalyst surfaces that were saturated with oxygen (O*) was the kinetically relevant step. Quasi‐equilibrated NO–NO2 interconversion steps established the coverage of * and O* and the chemical potential of oxygen during the catalysis. These chemical potentials set the oxidation state of Rh and Co clusters and were described by an O2 virtual pressure, which was determined from the formalism of non‐equilibrium thermodynamics. RhO2 and Co3O4 were the phases that were present during NO oxidation, which had several consequences for catalysis. Turnover rates increased with increasing cluster size because the vacancies that were needed for O2 activation were more abundant on large oxide clusters, which delocalized electrons better than small clusters. NO oxidation turnover rates on RhO2 and Co3O4 were higher than expected from the oxygen‐binding energy on Rh and Co metal surfaces and from the reduction potentials of Rh3+ and Co2+. These NO oxidation rates were consistent with the rates on Pt and PdO when one‐electron‐reduction processes, which were accessible for Rh4+ and Co3+ but not for Pt2+ and Pd2+, were used to describe the reactivity of RhO2 and Co3O4. One‐electron redox cycles caused the 16O2–18O2 exchange rates to be higher than the NO oxidation rates, in contrast with their analogous values on Pt and PdO, although O2 activation on the vacancies limited NO oxidation and O2 exchange on all of the catalysts. One‐electron redox cycles allowed electron sharing between metal cations and a facile route to form vacancies on RhO2 and Co3O4. This interpretation of the data highlighted the role of vacancies in kinetically relevant O2‐activation steps to explain the higher reactivity of larger metal and oxide clusters and to provide a common framework to describe NO oxidation and the active species on catalysts of practical interest.
Isomerization and Dimerization of Pinene using Al‐Incorporated MCM‐41 Mesoporous Materials
Authors: Zou Ji‐Jun , Chang Na , Zhang Xiangwen , Wang Li
Published: May 2012

A series of Al‐incorporated mobile crystalline materials (Al‐MCM‐41) were prepared by hydrothermal synthesis and characterized by XRD, N2 adsorption (isotherms), inductively coupled plasma (ICP) analysis, 27Al magic angle spinning (MAS) NMR spectroscopy, and in situ pyridine adsorption (IR analysis). All samples exhibit an ordered structure with the majority of Al species in framework positions, except those with an SiO2/Al2O3 ratio ≤10. The concentration of acid sites is closely related to the Al content in the unit cell. In the presence of Al‐MCM‐41, both α‐ and β‐pinenes are quickly transformed into isomerized products, which then couple to form homo‐ and heterodimers. Lewis acid sites are active in triggering both the isomerization and dimerization reactions, but weak Brønsted acid sites seem inactive for the dimerization. Al‐MCM‐41 has a greater activity than many other microporous and layered materials, and can be easily regenerated. The activity correlates well with the concentration of acid sites, and the sample with an SiO2/Al2O3 ratio of 20 shows the highest activity.
Robust PARAFAC for incomplete data
Authors: Hubert Mia , Van Kerckhoven Johan , Verdonck Tim
Published: May 2012

Different methods exist to explore multiway data. In this article, we focus on the widely used PARAFAC (parallel factor analysis) model, which expresses multiway data in a more compact way without ignoring the underlying complex structure. An alternating least squares procedure is typically used to fit the PARAFAC model. It is, however, well known that least squares techniques are very sensitive to outliers, and hence, the PARAFAC model as a whole is a nonrobust method. Therefore a robust alternative, which can deal with fully observed data possibly contaminated by outlying samples, has already been proposed in literature. In this paper, we present an approach to perform PARAFAC on data that contain both outlying cases and missing elements. A simulation study shows the good performance of our methodology. In particular, we can apply our method on a dataset in which scattering is detected and replaced with missing values. This is illustrated on a real data example. Copyright © 2012 John Wiley & Sons, Ltd.
Aromatic‐Amide‐Derived Olefins as a Springboard: Isomerization‐Initiated Palladium‐Catalyzed Hydrogenation of Olefins and Reductive Decarbonylation of Acyl Chlorides with Hydrosilane
Authors: Bai Xing‐Feng , Xu Li‐Wen , Zheng Long‐Sheng , Jiang Jian‐Xiong , Lai Guo‐Qiao , Shang Jun‐Yan
Published: May 2012

A highly efficient catalytic protocol for the isomerization of substituted amide‐derived olefins is presented that successfully uses a hydride palladium catalyst system generated from [PdCl2(PPh3)2] and HSi(OEt)3. The Z to E isomerization was carried out smoothly and resulted in geometrically pure substituted olefins. Apart from the cis–trans isomerization of double bonds, the selective reduction of terminal olefins and activated alkenes was performed with excellent functional group tolerance in the presence of an amide‐derived olefin ligand, and the products were obtained in high isolated yields (up to >99 %). Furthermore, the palladium/hydrosilane system was able to promote the reductive decarbonylation of benzoyl chloride when a (Z)‐olefin with an aromatic amide moiety was used as a ligand.
Liquid Chromatographic Separation of Darunavir Enantiomers on Coated and Immobilized Amylose Tris(3, 5‐Dimethylphenylcarbamate) Chiral Stationary Phases
Authors: Rao Ramisetti Nageswara , Kumar Kandukuri Nagesh , Naidu Challa Gangu
Published: May 2012

Liquid chromatographic separation of darunavir enantiomers on covalently bonded and physically adsorbed polysaccharide chiral stationary phases was studied at different temperatures. The separations were accomplished under normal‐phase conditions by using different combinations of hexane, organic modifiers (2‐propanol, 1‐propanol and ethanol), and diethylamine as mobile phase solvents. The effect of organic modifiers and the column temperature on retention, separation, and resolution was investigated. The observed differences were explained in terms of the coated and immobilized nature of the two columns. Van't Hoff plots (ln k′ vs. 1/T, ln α vs. 1/T) and apparent thermodynamic parameters were derived to understand the effect of temperature on separation. Chirality 24:652–660, 2012. © 2012 Wiley Periodicals, Inc.
Studies on the Solvation Dynamics of Coumarin 153 in 1‐Ethyl‐3‐Methylimidazolium Alkylsulfate Ionic Liquids: Dependence on Alkyl Chain Length
Authors: Kumar Das Sudhir , Sarkar Moloy
Published: May 2012

Steady‐state and time‐resolved fluorescence behavior of coumarin 153 (C153) is investigated in a series of 1‐ethyl‐3‐methylimidazolium alkylsulfate ([C2mim][CnOSO3]) ionic liquids differing only in the length of the linear alkyl chain (n=4, 6, and 8) in the anion. The aim of the present study is to understand the role of alkyl chain length in solute rotation and solvation dynamics of C153 in these ionic liquids. The blueshift observed in the steady‐state absorption and emission maxima of C153 on going from the C4OSO3 to the C8OSO3 system indicates increasing nonpolar character of the microenvironment of the solute with increasing length of the alkyl side chain of the anion of the ionic liquids. The average solvation time is also found to increase on changing the substituent from butyl to octyl, and this is attributed to the increase in the bulk viscosity of the ILs. A steady blueshift of the time‐zero maximum of the fluorescence spectrum with increasing alkyl chain length also indicates that the probe molecule experiences a less polar environment in the early part of the dynamics. Rotational dynamics of C153 are also analyzed by using the Stokes–Einstein–Debye (SED), Gierer–Wirtz (GW), and Dote–Kivelson–Schwartz (DKS) theories. Analyses of the results seem to suggest decoupling of the rotational motion of the probe from solvent viscosity.
Molecular genetic characterization of lymphoma: Application to cytology diagnosis
Authors: Ochs Rachel C. , Bagg Adam
Published: May 2012

Mature B‐ and T‐cell lymphomas are increasingly being associated with specific genetic alterations; characterization of these changes can sometimes be crucial to both diagnosis and prognosis. Molecular testing encompasses florescence in situ hybridization (FISH) and polymerase chain reaction (PCR)‐based assays, as well as classical cytogenetics. FISH and PCR‐based assays can be performed on cytology material without the need for advanced planning for testing with fresh tissue. As many lymphoproliferations are amenable to fine needle aspiration diagnosis, it is important for the cytopathologist to be aware of what testing is feasible in these (sometimes limited) specimens. Here, we review pertinent genetic changes in mature B‐ and T‐cell lymphomas with a focus on those that may be encountered more commonly in cytology specimens. Diagn. Cytopathol. 2012;40:542–555. © 2012 Wiley Periodicals, Inc.
The role of cytology specimens in molecular testing of solid tumors: Techniques, limitations, and opportunities
Authors: Aisner Dara L. , Sams Sharon B.
Published: May 2012

Numerous studies have demonstrated the suitability of cytology specimens for molecular analysis. When combined with the ability to acquire tissue in a minimally invasive manner, testing on cytology specimens is an especially attractive method for further refining diagnosis, determining prognosis, and predicting likely response to therapy as well as monitoring disease. As the demand for testing of small specimens increases, the burden of determining whether a specimen should be referred for testing will increasingly be placed on the pathologist. Although molecular laboratories that perform this testing will also evaluate the suitability of the specimen, familiarity with the criteria for suitability, which includes an understanding of the limitations of the assay methodology, will assist in determining which specimens are appropriate for referral. Selection of specimen(s) for testing should be paired with knowledge of the testing methodology used and its limitations, as well as the tumor enrichment capabilities of the laboratory. In addition to an expanding need to participate in the referral of specimens for testing, the cytopathologist will increasingly serve as a critical link in the communication between molecular laboratory and clinical team. Diagn. Cytopathol. 2012;40:511–524. © 2012 Wiley Periodicals, Inc.
Effects of adaptation, chance, and history on the evolution of the toxic dinoflagellate Alexandrium minutum under selection of increased temperature and acidification
Authors: Flores‐Moya Antonio , Rouco Mónica , García‐Sánchez María Jesús , García‐Balboa Camino , González Raquel , Costas Eduardo , López‐Rodas Victoria
Published: May 2012

The roles of adaptation, chance, and history on evolution of the toxic dinoflagellate Alexandrium minutum Halim, under selective conditions simulating global change, have been addressed. Two toxic strains (AL1V and AL2V), previously acclimated for two years at pH 8.0 and 20°C, were transferred to selective conditions: pH 7.5 to simulate acidification and 25°C. Cultures under selective conditions were propagated until growth rate and toxin cell quota achieved an invariant mean value at 720 days (ca. 250 and ca. 180 generations for strains AL1V and AL2V, respectively). Historical contingencies strongly constrained the evolution of growth rate and toxin cell quota, but the forces involved in the evolution were not the same for both traits. Growth rate was 1.5–1.6 times higher than the one measured in ancestral conditions. Genetic adaptation explained two‐thirds of total adaptation while one‐third was a consequence of physiological adaptation. On the other hand, the evolution of toxin cell quota showed a pattern attributable to neutral mutations because the final variances were significantly higher than those measured at the start of the experiment. It has been hypothesized that harmful algal blooms will increase under the future scenario of global change. Although this study might be considered an oversimplification of the reality, it can be hypothesized that toxic blooms will increase but no predictions can be advanced about toxicity.
Assembly of Saturated Nb/W Mixed‐Addendum Polyoxometalate [P2W15Nb3O62]9– and Lanthanide Ions (Ln = Eu, Ce)
Authors: Li Cong‐Cong , Liu Shu‐Xia , Li Shu‐Jun , Yang Yuan , Jin Hai‐Yan , Ma Feng‐Ji
Published: May 2012

Two isostructural polyoxotungstates, K6Na4H8[Eu6(H2O)38(P2W15Nb3O62)4]·45H2O (1) and K6Na4H8[Ce6(H2O)38(P2W15Nb3O62)4]·56H2O (2), have been synthesized by reactionof saturated Nb/W mixed‐addendum polyoxometalate [P2W15Nb3O62]9– and lanthanide ions in acidic solution. They are the first examples of lanthanide derivatives based on saturated Dawson‐type Nb/W mixed‐addendum polyoxometalates. All the compounds were fully characterized by single‐crystal X‐ray diffraction, IR spectroscopy, thermogravimetric analysis, elemental analysis, and electrochemistry. XRD analysis reveals that 1 and 2 display one‐dimensional chains constructed from sandwich‐type fragment {Ln3(P2W15Nb3O62)2} linked by alternating Ln–O–W bridging bonds. In 1 and 2, all the lanthanide ions selectively bind to Ot(Nb) of {P2W15Nb3O62} fragments (Ot: terminal oxygen atoms), indicating the high nucleophilicity of Ot(Nb). The photoluminescence behavior of 1 in the solid state was investigated at room temperature; it exhibits the characteristic transition of Eu under the excitation wavelength (394 nm). Additionally, the cyclic voltammogram of 2 indicates good electrocatalytic activity towards the reduction of nitrite.
Heck–Matsuda Arylation as a Strategy to Access Kavalactones Isolated from Polygala sabulosa, Piper methysticum, and Analogues
Authors: Soldi Cristian , Moro Angélica V. , Pizzolatti Moacir G. , Correia Carlos R. D.
Published: May 2012

Herein, we describe the total syntheses of three bioactive pyrones isolated from Polygala sabulosa (i.e., 1, 4, and 7) and eight isolated from Piper methysticum (i.e., 8–10, 13, 15, and 18–20) using the Heck–Matsuda arylation as the key strategy. The evaluation of this methodology by employing different arenediazonium tetrafluoroborates revealed that the Heck arylation was more efficient when the olefin undergoing arylation possessed the vinyl‐2‐pyrone structural unit instead of the vinyl dihydro‐2‐pyrone moiety. The Heck–Matsuda arylation of many of the examined olefins proceeded in a practical manner with total regio‐ and stereocontrol.
Landslide Amplification by Liquefaction of Runout‐Path Material after the 2008 Wenchuan (M 8·0) Earthquake, China
Authors: Wang Gonghui , Huang Runqiu , Chigira Masahiro , Wu Xiyong , Lourenço Sérgio D. N.
Published: May 2012

Here, we propose that an earthquake can trigger the failure of a landslide mass while simultaneously triggering liquefaction of runout‐path materials before the arrival of the landslide mass, thus greatly increasing the size and mobility of an overriding landslide. During the 2008 Wenchuan earthquake, about 60 000 landslides were triggered, directly resulting in about 20 000 casualties. While these landslides mainly originated from steep slopes, some landslides with high mobility formed in colluvial valley deposits. Among these, the most catastrophic was the Xiejiadian landslide in Pengzhou city, which traveled hundreds of meters before coming to rest. Through field investigation and laboratory testing, we conclude that this landslide primarily formed from colluvial deposits in the valley and secondarily from failure of slopes in granitic rock located uphill. Much of the granitic slope failure was deposited in the upper part of the travel path (near the slide head); the remainder was dispersed throughout the main landslide deposit. Superposition of deposits at the landslide toe indicates that landslide debris derived from colluvial soil was deposited first. The deposits at the landslide toe displayed flow characteristics, such as fine materials comprising basal layers and large boulders covering the deposit surface. We hypothesize that the main part of the landslide resulted from seismogenic liquefaction of valley colluvium, rather than from liquefaction potentially caused by undrained loading from the granitic slope failures impacting the colluvium. To examine the likelihood that seismogenic liquefaction occurred, we took samples from different areas of the landslide deposit and performed undrained cyclic shear tests on them in the laboratory. The results showed that the sandy soils that comprise most of the deposit are highly liquefiable under seismic loading. Therefore, we conclude that liquefaction of the colluvium in the valley during the earthquake was the main reason for this rapid (~46 m/s) long‐runout (1·7 km) landslide. Copyright © 2012 John Wiley & Sons, Ltd.
Using in situ pore water concentrations to estimate the phytotoxicity of nicosulfuron in soils to corn (Zea mays L.)
Authors: Liu Kailin , Cao Zhengya , Pan Xiong , Yu Yunlong
Published: May 2012

The phytotoxicity of an herbicide in soil is typically dependent on the soil characteristics. To obtain a comparable value of the concentration that inhibits growth by 50% (IC50), 0.01 M CaCl2, excess pore water (EPW) and in situ pore water (IPW) were used to extract the bioavailable fraction of nicosulfuron from five different soils to estimate the nicosulfuron phytotoxicity to corn (Zea mays L.). The results indicated that the phytotoxicity of nicosulfuron in soils to corn depended on the soil type, and the IC50 values calculated based on the amended concentration of nicosulfuron ranged from 0.77 to 9.77 mg/kg among the five tested soils. The range of variation in IC50 values for nicosulfuron was smaller when the concentrations of nicosulfuron extracted with 0.01 M CaCl2 and EPW were used instead of the amended concentration. No significant difference was observed among the IC50 values calculated from the IPW concentrations of nicosulfuron in the five tested soils, suggesting that the concentration of nicosulfuron in IPW could be used to estimate the phytotoxicity of residual nicosulfuron in soils. Environ. Toxicol. Chem. 2012; 31: 1705–1711. © 2012 SETAC
Development of a molecular biomarker for detecting intersex after exposure of male medaka fish to synthetic estrogen
Authors: Zhao Yanbin , Hu Jianying
Published: May 2012

Although intersex of fish species has been widely reported in aquatic environments, there is no appropriate biomarker of the effects to assess the occurrence of intersex. In the present study, mRNA expression profiles of 14 genes, which are either involved in ovary development and maintenance or have relatively high mRNA transcription levels in ovarian gene expression profiles in fish species, were comprehensively evaluated in male Japanese medaka (Oryzias latipes) exposed to 17α-ethynylestradiol (EE2) to investigate their utility as indicators of the severity index of intersex. Of these 14 genes, mRNA expression of a novel gene, termed ovary structure protein 1 (OSP1) in the present study, showed female-like expression pattern with the highest transcription levels, and displayed the most significantly positive correlation with the severity index of intersex (r2 = 0.8215, p < 0.0001). The full-length mRNA sequence of OSP1 is 802 bp, with an open reading frame (ORF) of 642 bp that encodes a 214-amino acid peptide. Reverse transcription polymerase chain reaction and in situ hybridization revealed that OSP1 was expressed exclusively in the ovaries, specifically in the oogonia and primary oocytes in ovaries and in testis with intersex. These results suggest that the analysis of mRNA expression of OSP1 can be used to indicate intersex in male medaka. Environ. Toxicol. Chem. 2012; 31: 1765–1773. © 2012 SETAC
Protein‐based carbon capture: progress and potential
Authors: Drummond Michael L. , Cundari Thomas R. , Wilson Angela K.
Published: May 2012

Increasing atmospheric levels of CO2 and potential resulting climate changes require new, innovative solutions. As currently employed, carbon capture and sequestration (CCS) technology is unable, by orders of magnitude, to cope with the tremendous (and increasing) amount of anthropogenic CO2 emissions. In the biosphere, enzymatic CCS captures more than quadruple the amount of CO2 emitted by human activity, and so a bio‐inspired approach to CCS is greatly appealing. In this perspective, recent work concerning the ability of various CO2‐utilizing enzymes (Rubisco, carbonic anhydrase, and others) to act as carbon capture agents is discussed. Particular attention is given to computational modeling and simulation research, which has revealed useful, fundamental information about the way a protein interacts with carbon dioxide at the primary, secondary, and tertiary structure levels. Novel computational approaches that have been developed to rapidly screen proteins for their suitability for enzymatic CCS are discussed. It is proposed that increased carbon utilization must be incorporated into CCS, and furthermore that enzymatic utilization, especially when guided by computational modeling, will be a crucial component of success. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
T‐cell acute lymphoblastic leukaemia after liver transplantation: post‐transplant lymphoproliferative disorder or coincidental de novo leukaemia?
Authors: Fang Yanan , Pinkney Kerice A , Lee John C , Gindin Tatyana , Weiner Michael A , Alobeid Bachir , Bhagat Govind
Published: May 2012

Post‐transplant lymphoproliferative disorders of T‐cell origin are quite uncommon, and the vast majority represent neoplasms of mature, post‐thymic T‐ or natural killer cells. Here, we report a rare case of T‐cell acute lymphoblastic leukaemia (T‐ALL), which occurred in an 18‐year‐old man who had undergone three liver transplants, initially for biliary atresia and subsequently for graft failure due to chronic rejection. He had received immunosuppression with cyclosporine and tacrolimus, as well as short‐term treatment with OKT3. The T‐ALL occurred 16 years after the first liver transplant. This case highlights the challenge for classifying rare neoplasms occurring in recipients of solid organ transplants that are currently not recognized to lie within the spectrum of post‐transplant lymphoproliferative disorders. Given the long interval between the liver transplants and the development of T‐ALL, a coincidental occurrence of the leukaemia cannot be ruled out. However, the potential roles of immunosuppressive therapy and other co‐morbid conditions of the individual as possible risk factors for the pathogenesis of T‐ALL are discussed. Copyright © 2012 John Wiley & Sons, Ltd.
EMPIRICAL ANALYSIS OF SPECULATIVE ATTACKS WITH CONTRACTIONARY REAL EFFECTS
Authors: Arciniegas Rueda Ismael
Published: May 2012

The effects of a currency crisis on a country's economy depend on nonlinear relations among several variables that characterize the economic, financial, legal and socio‐political structure of the country at the onset of the crisis. Those effects can be associated with contractions or expansions in output. Historically, contractionary speculative attacks are more frequent. This paper uses a parametric censored heteroscedastic TOBIT model to empirically analyse how different economic and financial variables determine the real effects of a contractionary speculative attack. Variables describing the banking sector, the international trade, the severity of the crisis and foreign interest rates are found to be significant in explaining the size of currency crises' contractionary real effects. The TOBIT's results are compared with alternative modelling strategies. Copyright © 2012 John Wiley & Sons, Ltd.