bluuebunny/crossref_metadata_2025 huggingface dataset:
The balloon dilation of the pulmonary valve during early repair of tetralogy of Fallot
Authors: Vida Vladimiro L. , Padalino Massimo A. , Maschietto Nicola , Biffanti Roberta , Anderson Robert H , Milanesi Ornella , Stellin Giovanni
Published: May 2012

Background and objective

Progressive pulmonary valve (PV) regurgitation leads to right ventricular failure after repair of tetralogy of Fallot (TOF). We sought to evaluate our results with the preservation of the PV in selected patients with TOF.

Methods

All patients with TOF who were scheduled for PV's preservation between June 2007 and May 2010 were enrolled. Surgical correction involved the combination of early transatrial repair and intraoperative balloon dilation of the PV annulus.

Results

Of 18 patients, 16 (89%) underwent a successful preservation of the PV. Median age at surgery was 3.1 months (range 2.4–4.7 months). Median preoperative PV Z‐score was −2.5 (range −1.4 to −3.12) and the median peak right ventricle outflow tract (RVOT) gradient was 80 mm Hg (range 49–90 mm Hg). No procedure‐related complications were reported. The size of the PV annulus after the balloon dilation was appropriate for body surface area in all patients. Median follow‐up time was 1.4 years (range 0.5–3.3 years). Reoperation was needed in one patient 3 months after repair because of residual subvalvar RVOT obstruction. The remaining 15 patients are alive and well. The median PV Z‐score is 0 (range −0.2 to 1). Median peak RVOT gradient is 20 mm Hg (range 12–32 mm Hg). The PV is competent in seven patients; mild PV regurgitation is present in seven patients and moderate in one.

Conclusions

The integrity of the PV annulus and PV function can be preserved in selected patients during early repair of TOF when using concomitant balloon dilation. The PV preservation will hopefully prevent long‐standing RV dysfunction. © 2012 Wiley Periodicals, Inc.
Cross‐validation in PCA models with the element‐wise k‐fold (ekf) algorithm: theoretical aspects
Authors: Camacho José , Ferrer Alberto
Published: May 2012

Cross‐validation has become one of the principal methods to adjust the meta‐parameters in predictive models. Extensions of the cross‐validation idea have been proposed to select the number of components in principal components analysis (PCA). The element‐wise k‐fold (ekf) cross‐validation is among the most used algorithms for principal components analysis cross‐validation. This is the method programmed in the PLS_Toolbox, and it has been stated to outperform other methods under most circumstances in a numerical experiment. The ekf algorithm is based on missing data imputation, and it can be programmed using any method for this purpose. In this paper, the ekf algorithm with the simplest missing data imputation method, trimmed score imputation, is analyzed. A theoretical study is driven to identify in which situations the application of ekf is adequate and, more importantly, in which situations it is not. The results presented show that the ekf method may be unable to assess the extent to which a model represents a test set and may lead to discard principal components with important information. On a second paper of this series, other imputation methods are studied within the ekf algorithm. Copyright © 2012 John Wiley & Sons, Ltd.
N‐Heterocyclic Tridentate Aromatic Ligands Bound to [Ln(hexafluoroacetylacetonate)3] Units: Thermodynamic, Structural, and Luminescent Properties
Authors: Zaïm Amir , Nozary Homayoun , Guénée Laure , Besnard Céline , Lemonnier Jean‐François , Petoud Stéphane , Piguet Claude
Published: May 2012

Herein, we discuss how, why, and when cascade complexation reactions produce stable, mononuclear, luminescent ternary complexes, by considering the binding of hexafluoroacetylacetonate anions (hfac−) and neutral, semi‐rigid, tridentate 2,6‐bis(benzimidazol‐2‐yl)pyridine ligands (Lk) to trivalent lanthanide atoms (LnIII). The solid‐state structures of [Ln(Lk)(hfac)3] (Ln=La, Eu, Lu) showed that [Ln(hfac)3] behaved as a neutral six‐coordinate lanthanide carrier with remarkable properties: 1) the strong cohesion between the trivalent cation and the didentate hfac anions prevented salt dissociation; 2) the electron‐withdrawing trifluoromethyl substituents limited charge‐neutralization and favored cascade complexation with Lk; 3) nine‐coordination was preserved for [Ln(Lk)(hfac)3] for the complete lanthanide series, whilst a counterintuitive trend showed that the complexes formed with the smaller lanthanide elements were destabilized. Thermodynamic and NMR spectroscopic studies in solution confirmed that these characteristics were retained for solvated molecules, but the operation of concerted anion/ligand transfers with the larger cations induced subtle structural variations. Combined with the strong red photoluminescence of [Eu(Lk)(hfac)3], the ternary system LnIII/hfac−/Lk is a promising candidate for the planned metal‐loading of preformed multi‐tridentate polymers.
Catalytic Enantioselective Halolactonization of Enynes and Alkenes
Authors: Zhang Wei , Liu Na , Schienebeck Casi M. , Decloux Kyle , Zheng Suqing , Werness Jenny B. , Tang Weiping
Published: May 2012

New organocatalysts have been developed for the enantioselective halolactonization of (Z)‐1,3‐enynes and 1,1‐disubstituted alkenes. In the case of 1,3‐enynes, the carboxylate nucleophile and halogen electrophile were added to the conjugated π‐system from the same face. Up to 99 % ee was achieved for the 1,4‐syn‐bromolactonization of conjugated (Z)‐1,3‐enynes. Based on the results from the enyne halolactonization, a second generation of catalysts was designed for simple olefins. Up to 91 % ee was observed for chlorolactonization of 1,1‐disubstituted alkenes. The catalysts developed for the enantioselective halolactonization of both enynes and alkenes are composed of a cinchona alkaloid skeleton tethered to a urea group.
Anion‐Induced Shuttling of a Naphthalimide Triazolium Rotaxane
Authors: Spence Graeme T. , Pitak Mateusz B. , Beer Paul D.
Published: May 2012

The anion‐templated synthesis of a rotaxane structure, incorporating the new naphthalimide triazolium motif, is described and the interlocked host shown to exhibit selective, uni‐directional, anion‐induced shuttling. Initial pseudorotaxane investigations demonstrate the ability of a naphthalimide triazolium threading component to form interpenetrated assemblies with counter‐anion‐dependent co‐conformations. 1H NMR studies reveal that the shuttling behaviour of the analogous rotaxane host system is controlled by selective anion binding and by the nature of the solvent conditions. Complete macrocycle translocation only occurs upon the recognition of the smaller halide anions (chloride and bromide). The rotaxane solid‐state crystal structure in the presence of chloride is in agreement with the solution‐phase co‐conformation. The sensitivity of the axle naphthalimide absorbance band to the position of the macrocycle component within the interlocked structure enabled the molecular motion to be observed by UV/Vis spectroscopy, and the chloride‐induced shuttling of the rotaxane was reversed upon silver hexafluorophosphate addition.
Considerations of Noise and Measurement Reproducibility of Circular Dichroism Measurements Using Na[CoIII(EDDS)]
Authors: Chmel Nikola Paul , Scott Peter , Rodger Alison
Published: May 2012

Although circular dichroism (CD) spectroscopy has become ubiquitous in biological, chemical, and pharmacological laboratories, several issues with instrument calibration and standardization, measurements quality, and reproducibility still remain. In the context of validating and developing a wide‐wavelength‐range stable standard for CD that is available in both enantiomeric forms, (R,R)‐ and (S,S)‐Na[CoIII(EDDS)] (where EDDS is ethylenediaminedisuccinato), we have become aware of sources of error in CD spectroscopy in addition to instrument calibration and user issues. This article summarizes those errors and suggests procedures for minimizing them by averaging over sufficient independent data accumulations with appropriate parameters. Chirality 24:699–705, 2012. © 2012 Wiley Periodicals, Inc.
A simple calorimeter to measure specific heat of activated carbon prepared for pressure swing adsorption refrigeration system
Authors: Anupam Kumar , Halder G. N. , Roy Zunipa , Sarkar S. C. , Yadav Akshat
Published: May 2012

A new calorimeter to measure specific heat of indigenously prepared granular activated carbon (AC) for application in a refrigeration system based on gas adsorption–desorption mechanism is presented. This calorimeter allows specific heat measurements in high (305.5–317.8 K) as well as low (254.6–264 K) temperature ranges. The specific heat of prepared AC on measurement using developed calorimeter has been found to be 1.062 J g−1 K−1. Preparation, instrumental analyses and influence of various physical properties of AC on its specific heat have also been discussed. Characterisation results of AC demonstrate that it can be efficiently used in such cold producing system down to refrigeration and cryogenic temperature. © 2012 Canadian Society for Chemical Engineering
Synthesis of Hydrazone‐Modified Nucleotides and Their Polymerase Incorporation onto DNA for Redox Labeling
Authors: Raindlová Veronika , Pohl Radek , Klepetářová Blanka , Havran Luděk , Šimková Eva , Horáková Petra , Pivoňková Hana , Fojta Miroslav , Hocek Michal
Published: May 2012

5‐(5‐Formylthiophen‐2‐yl)cytosine, 7‐(5‐formylthiophen‐2‐yl)‐7‐deazaadenosine 2′‐deoxyribonucleosides, and their 5′‐O‐triphosphates (dNTPs) were converted into the 2,4‐dinitrophenylhydrazone or nitrobenzofurazanyl. The hydrazone‐modified dNTPs were enzymatically incorporated into DNA by polymerase catalyzed primer extension (PEX). This direct incorporation of hydrazone‐linked dNTPs was compared to previously reported incorporation of aldehyde‐modified dNTPs followed by postsynthetic hydrazone formation on DNA to show that the direct incorporation can be used for incorporation of more hydrazone units, however, cleaner PEX products are formed by incorporation of aldehydes and subsequent reaction with hydrazines. Extensive study of electrochemical behavior of the nitroarylhydrazone‐linked nucleosides and DNA was performed confirming the potential utility of the hydrazone, nitroaryl, and benzofurazane groups for redox labeling of DNA.
Phase Change of Nickel Phosphide Catalysts in the Conversion of Cellulose into Sorbitol
Authors: Yang Pengfei , Kobayashi Hirokazu , Hara Kenji , Fukuoka Atsushi
Published: May 2012

Nickel phosphide catalysts supported on activated carbon were tested for the conversion of cellulose in water. High sorbitol yields of over 60 % were obtained with high cellulose conversions at 503 K and 5 MPa of H2. It is interesting that an amorphous nickel phosphide phase is generated from a crystalline phase during the increase in temperature and that the amorphous phase is responsible for the high yield of sorbitol. The optimization of the reaction parameters indicates that the increase of the amorphous part in the cellulose is the key to obtaining high yields of sorbitol. A phase change of the nickel phosphide is observed, which can be correlated to the change in catalytic activity.
Solvent Effects on the Hydrogenolysis of Diphenyl Ether with Raney Nickel and their Implications for the Conversion of Lignin
Authors: Wang Xingyu , Rinaldi Roberto
Published: May 2012

The conversion of lignin, the most recalcitrant of the biopolymers, is necessary for a carbon‐efficient utilization of lignocellulosic materials. In this context, hydrogenolysis of lignin is a process receiving increasing attention. In this report, the solvent effects on the hydrogenolysis of diphenyl ether and lignin with Raney Ni are addressed. The Lewis basicity of the solvent very much affects the catalytic activity, so Raney Ni in nonbasic solvents is an extremely active catalyst for hydrogenolysis and hydrogenation. In basic solvents, however, Raney Ni is a less active, but much more selective catalyst for hydrogenolysis while preserving the aromatic products. With regard to the reactions with lignin, assessing the complexity of the product mixtures by two‐dimensional GC×GC–MS revealed solvent effects on the product distribution. Reaction in methylcyclohexane resulted in cyclic alcohols and cyclic alkanes, whereas reaction in 2‐propanol led to cyclic alcohols, cyclic ketones, and unsaturated products. The hydrogenolysis of lignin in methanol, however, produced mostly phenols. Overall, these results demonstrate that the solvent plays a key role in directing the selectivity and, thus, it must be taken into consideration in the design of catalytic systems for conversion of lignin by hydrogenolysis of CO ether bonds.
Sleep and sleepiness among first‐time postpartum parents: A field‐ and laboratory‐based multimethod assessment
Authors: Insana Salvatore P. , Montgomery‐Downs Hawley E.
Published: May 2012

The study aim was to compare sleep, sleepiness, fatigue, and neurobehavioral performance among first‐time mothers and fathers during their early postpartum period. Participants were 21 first‐time postpartum mother–father dyads (N = 42) and seven childless control dyads (N = 14). Within their natural environment, participants completed 1 week of wrist actigraphy monitoring, along with multi‐day self‐administered sleepiness, fatigue, and neurobehavioral performance measures. The assessment week was followed by an objective laboratory‐based test of sleepiness. Mothers obtained more sleep compared to fathers, but mothers' sleep was more disturbed by awakenings. Fathers had greater objectively measured sleepiness than mothers. Mothers and fathers did not differ on subjectively measured sleep quality, sleepiness, or fatigue; however, mothers had worse neurobehavioral performance than fathers. Compared to control dyads, postpartum parents experienced greater sleep disturbance, sleepiness, and sleepiness‐associated impairments. Study results can inform social policy, postpartum sleep intervention development, and research on postpartum family systems and mechanisms that propagate sleepiness. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 361–372, 2013
The influence of natural flow regimes on macroinvertebrate assemblages in a semiarid Mediterranean basin
Authors: Belmar O. , Velasco J. , Gutiérrez‐Cánovas C. , Mellado‐Díaz A. , Millán A. , Wood P. J.
Published: May 2012

The investigation of flow–ecology relationships constitutes the basis for the development of environmental flow criteria. The need to understand hydrology–ecology linkages in natural systems has increased owing to the prospect of climate change and flow regime management, especially in water‐scarce areas such as Mediterranean basins. Our research quantified the macroinvertebrate community response at family, genus and species level to natural flow regime dynamics in freshwater streams of a Mediterranean semiarid basin (Segura River, SE Spain) and identified the flow components that influence the composition and richness of biotic assemblages. Flow stability and minimum flows were the principal hydrological drivers of macroinvertebrate assemblages, whereas the magnitude of average and maximum flows had a limited effect. Perennial stable streams were characterized by flow sensitive lotic taxa (Ephemeroptera, Plecoptera and Trichoptera) and intermittent streams by predominately lentic taxa (Odonata, Coleoptera, Heteroptera and Diptera). Relatively minor biological changes were recorded for intermediate flow regime classes along a gradient of flow stability. Seasonal variation and minimum flows are key hydrological components that need to be considered for river management and environmental flows in the Segura River basin and other Mediterranean basins. The anthropogenic modification of these parameters, due to both human activities and climate change, would probably lead to significant changes in the structure and composition of communities in perennial stable streams. This would be characterized by a reduction of flow sensitive Ephemeroptera, Plecoptera and Trichoptera taxa and an increase in more resilient Odonata, Coleoptera, Heteroptera and Diptera taxa. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis of CLA‐enriched TAG by Candida antarctica lipase under vacuum
Authors: Hong Seung In , Kim Yangha , Yoon Sung Won , Cho Seung Yong , Kim In‐Hwan
Published: May 2012

Conjugated linoleic acid (CLA)‐enriched triacylglycerol (TAG) of 90 wt% was successfully synthesized in 10 h by direct esterification of glycerol and CLA using an immobilized lipase from Candida antarctica under vacuum. The best operating conditions for the synthesis of TAG were investigated according to the three parameters of temperature, enzyme loading, and vacuum. The synthesis of TAG increased with increasing temperature but it did not significantly change above 60°C (p>0.05). The increase of enzyme loading lead to an enhanced conversion of TAG, but enzyme loading of more than 10% (based on the total weight of the substrates) was not effective. Moreover, when vacuum increased, the conversion of TAG increased, but the conversion rate decreased when the vacuum level was too high. The best combination of temperature, enzyme loading, and vacuum level were 60°C, 10% of the total weight of the substrates, and 0.4 kPa, respectively. During the initial 6 h of reaction, Candida antarctica lipase had more selectivity for 10t,12c‐CLA than 9c,11t‐CLA onto the glycerol backbone, and a preference for the incorporation at the sn‐1,3 positions of glycerol rather than at the sn‐2 position.
Synthesis and properties of novel alkyl sulfate gemini surfactants
Authors: Tai Shuxin , Gao Zhinong , Liu Xueguo , Zhang Qi
Published: May 2012

Four anionic gemini surfactants of the sulfate type C12CnC12, where n is the spacer chain length (n = 3, 4, 6, and 10) were synthesized. The structures of these surfactants were confirmed by FT‐IR, 1H NMR, ESI mass spectra (ESI‐MS), and elemental analysis. The surface‐active properties of these compounds were investigated by means of surface tension, electrical conductivity, and fluorescence measurements. Premicellar aggregations were found for the four gemini surfactants, as revealed by the conductivity measurement. The formation of premicellar aggregates may account for the discrepancy between the critical micelle concentration (cmc) obtained by the surface tension and conductivity measurement. The cmc values of these gemini surfactants were much lower than that of sodium dodecylsulfate (SDS) and decreased monotonously with the increase of spacer chain length from 3 to 10. The effect of spacer chain length on the performance properties like foaming, emulsion stability, and lime soap dispersing ability were also studied and discussed.

Practical applications: Alkyl sulfate surfactants are one of the most widely used surfactants. The new alkyl sulfate gemini surfactants synthesized in our study are more surface‐active than sodium dodecylsulfate. These gemini surfactants possess low critical micelle concentrations, high emulsion stability, and excellent lime soap dispersing ability. They have potential applications in the fields of cosmetics, detergents, etc.
Total Syntheses of Dichotomines A–D and the Stereochemical Revision of Dichotomines B–D
Authors: Zhang Qiang , Dong Jing , Shi Xiao‐Xin , Lu Xia
Published: May 2012

New asymmetric total syntheses of (–)‐dichotomines A–D (1–4) starting from L‐tryptophan methyl ester and 2,3‐O‐isopropylidene‐D‐glyceraldehyde are described. The absolute configuration of the stereogenic center of (–)‐dichotomine A (1) was reconfirmed as (S), on the basis of the X‐ray crystallographic analysis of the conjugate (i.e., 17) of its methyl ester (i.e., 16) with (S)‐N‐tosylproline, whereas the absolute configurations of the stereogenic centers of (–)‐dichotomines B–D (2–4) were revised as (R).
One‐Pot Oxidation–Hydrocyanation Sequence Coupled to Lipase‐Catalyzed Diastereoresolution in the Chemoenzymatic Synthesis of Sugar Cyanohydrin Esters (Eur. J. Org. Chem. 14/2012)
Authors: Hietanen Ari , Kanerva Liisa T.
Published: May 2012

The cover picture shows the key intermediates in the chemoenzymatic sequence in one‐pot from peracetylated methyl α‐D‐glycosides into sugar cyanohydrin acetates. The method allows the stereoselective substitution of hydrogen with a nitrile group through labile intermediates that are not separated. Lipase from Burkholderia cepacia, a key enzyme responsible for selectivity in the sequence, is shown in the middle (adopted from pdb entry 1OIL). Details are discussed in the article by A. Hietanen and L. T. Kanerva on p. 2729 ff.

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Multiple‐slider surfaces bearing for seismic retrofitting of frame structures with soft first stories
Authors: Fakhouri Muhannad Y. , Igarashi Akira
Published: May 2012

A new isolation interface is proposed in this study to retrofit existing buildings with inadequate soft stories as well as new structures to be constructed with soft first story intended for architectural or functional purposes. The seismic interface is an assembly of bearings set in parallel on the top of the first story columns: the multiple‐slider bearings and rubber bearings. The multiple‐slider bearing is a simple sliding device consisting of one horizontal and two inclined plane sliding surfaces based on polytetrafluoroethylene and highly polished stainless steel interface at both ends set in series. A numerical example of a five‐story reinforced concrete shear frame with soft first story is considered and analyzed to demonstrate the efficiency of the proposed isolation system in reducing the ductility demand and damage in the structure while maintaining the superstructure above the bearings to behave nearly in the elastic range with controlled bearing displacement. Comparative study with the conventional system as well as various isolation systems such as rubber bearing interface and resilient sliding isolation is carried out. Moreover, an optimum design procedure for the multiple‐slider bearing is proposed through the trade‐off between the maximum bearing displacement and the first story ductility demand ratio. The results of extensive numerical analysis verify the effectiveness of the multiple‐slider bearing in minimizing the damage from earthquake and protecting the soft first story from excessively large ductility demand. Copyright © 2012 John Wiley & Sons, Ltd.
Promoting effects on reproduction increase population vulnerability of Daphnia magna
Authors: Agatz Annika , Hammers-Wirtz Monika , Gabsi Faten , Ratte Hans Toni , Brown Colin D. , Preuss Thomas G.
Published: May 2012

Environmental risk assessment of chemicals is based on single species tests at the individual level with single compounds. However, the protection goal is the sustainability of a population, which faces several natural stressors and mixtures of chemicals in the environment. Therefore, experiments were undertaken to quantify the combined effects of chemicals with different modes of action on Daphnia magna populations. Populations continuously exposed to dispersogen A and at abundance equilibrium were treated with a 2-d pulse of p353-nonylphenol. In previous studies, dispersogen A was shown to act as a natural info-chemical, promoting the reproduction of daphnids (higher offspring quantity) coupled with reduced offspring fitness, whereas nonylphenol in pulsed-exposure caused size-selective mortality. Dispersogen A caused accelerated population growth to maximum abundance, shifted the population structure towards smaller individuals, and increased the population sensitivity to nonylphenol. The authors showed that a positive effect observed at the individual level can be transposed to a negative effect when monitored at the population level. So far, positive effects are not addressed in environmental risk assessment, and even in higher-tier testing, population structure is not quantified. Both factors indicate a potential mismatch between protection aim and risk assessment practice. Environ. Toxicol. Chem. 2012; 31: 1604–1610. © 2012 SETAC
Reprioritizing Genetic Associations in Hit Regions Using LASSO‐Based Resample Model Averaging
Authors: Valdar William , Sabourin Jeremy , Nobel Andrew , Holmes Christopher C.
Published: May 2012

Significance testing one SNP at a time has proven useful for identifying genomic regions that harbor variants affecting human disease. But after an initial genome scan has identified a “hit region” of association, single‐locus approaches can falter. Local linkage disequilibrium (LD) can make both the number of underlying true signals and their identities ambiguous. Simultaneous modeling of multiple loci should help. However, it is typically applied ad hoc: conditioning on the top SNPs, with limited exploration of the model space and no assessment of how sensitive model choice was to sampling variability. Formal alternatives exist but are seldom used. Bayesian variable selection is coherent but requires specifying a full joint model, including priors on parameters and the model space. Penalized regression methods (e.g., LASSO) appear promising but require calibration, and, once calibrated, lead to a choice of SNPs that can be misleadingly decisive. We present a general method for characterizing uncertainty in model choice that is tailored to reprioritizing SNPs within a hit region under strong LD. Our method, LASSO local automatic regularization resample model averaging (LLARRMA), combines LASSO shrinkage with resample model averaging and multiple imputation, estimating for each SNP the probability that it would be included in a multi‐SNP model in alternative realizations of the data. We apply LLARRMA to simulations based on case‐control genome‐wide association studies data, and find that when there are several causal loci and strong LD, LLARRMA identifies a set of candidates that is enriched for true signals relative to single locus analysis and to the recently proposed method of Stability Selection. Genet. Epidemiol. 36:451‐462, 2012. © 2012 Wiley Periodicals, Inc.
Competition barriers and strategy moderations: Impact on foreign subsidiary performance
Authors: Pehrsson Anders
Published: May 2012

The global firm needs to recognize the crucial role of foreign subsidiary strategy in building global competitive advantage and emphasize corporate control of important strategy elements. In particular, there is a need to examine the role of foreign subsidiary strategy in the firm's efforts to break through local barriers to competition that obstructs the search for global competitive advantage. This study seeks answers to two questions. First, how does the business relatedness between a foreign subsidiary and the parent firm moderate the performance impact of local competition barriers? Second, how does the business strategy of a foreign subsidiary moderate the performance impact of local competition barriers? To test contingency hypotheses, the study used data from 191 subsidiaries in Germany, the United Kingdom, and the United States. The subsidiaries belong to Swedish manufacturing firms. It was found that greater business relatedness and business scope of the subsidiary weaken the negative impact of competition barriers on subsidiary performance, while product differentiation and customer responsiveness differentiation have no moderating effects. The study contributes to theory on control of foreign subsidiaries by extending the knowledge of strategy drivers of foreign subsidiary performance, and the knowledge facilitates the formulation of effective global strategies. Copyright © 2012 Strategic Management Society.
The global strategy of emerging multinationals from China
Authors: Peng Mike W.
Published: May 2012

The global strategy of multinational enterprises (MNEs) from China started to emerge recently. While sizable components of their strategy and behavior are consistent with what we observe of MNEs from other countries, Chinese MNEs are characterized by three relatively unique aspects: (1) the previously underappreciated role played by the home country governments of MNEs as an institutional force, (2) the challenge of going abroad in the absence of significantly superior technological and managerial resources, and (3) the rapid adoption of (often high‐profile) acquisitions as a primary mode of entry. Overall, this article argues that these three relatively unique aspects of emerging multinationals from China will have significant ramifications for future theory building and empirical efforts of the global strategy research community. Copyright © 2012 Strategic Management Society.
Electron ionization mass spectra of organophosphorus compounds, Part II: Mass spectrometric fragmentation of spiro(indene‐2,3′‐pyrazole)phosphonates, spiro(indene‐2,3′‐pyrazole)phosphanylidene, spiro(1,2,4‐diazaphosphole‐3,2′‐indenes), and (1,3‐dioxo‐2H‐isoindolyl)phosphonate derivatives
Authors: Salem Mounir A. I. , Marzouk Magda I. , Ali Tarik E. , Khidre Rizk E.
Published: May 2012

Fragmentation pathways of nine synthetic organophosphorus compounds, belonging to the following types spiro(indene‐2,3′‐pyrazole)‐ phosphanylidene, spiro(indene‐2,3′‐pyrazole)phos‐ phonates, spiro(1,2,4‐diazaphosphole‐3,2′‐indenes), and (1,3‐dioxo‐1,3‐dihydro‐2H‐isoindol‐2‐yl) phosphonates, were investigated by electron impact mass spectrometry with the aim of obtaining a better understanding of their fragmentation processes. The intensity of recorded molecular ion peaks showed various values depending on the nature of compounds. Characteristic fragment ions were formed by successive loss of simple side functional groups followed by decomposition of indenyl‐1,3‐dione and isoindole‐1,3‐dione moieties connected with terminal groups or heterocycles. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:254–264, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21011
Costing neonatal care alongside the collaborative ecmo trial: How much primary research is required?
Authors: Howard Sarah , Mugford Miranda , Elbourne Diana , Johnson Ann , Enock Katie , Normand Charles , Field David , Grant Adrian
Published: May 2012

Researchers working on economic evaluations alongside trials have to balance minimising data collection with maximising the ability to measure differences in costs. Using existing data sources may keep the costs of research down, but these data may not be entirely appropriate to the evaluation question. When evaluating technologies in intensive care it is particularly important to be able to classify patients correctly by their resource requirements especially when those requirements vary considerably from day to day.

This paper describes and justifies methods for costing the care provided for babies in (one arm of) an on‐going multi‐ centre trial, the Collaborative ECMO trial.1 This trial is evaluating alternative policies of life support for mature (full term) newborn babies with severe respiratory failure. The most reliable cost information on neonatal intensive care is available from a study, conducted independently from the trial, which has used simple cost apportionment on a large sample of units. By drawing on clinical opinion and carrying out a case note exercise we assessed whether this available information was appropriate to estimate ‘baseline’ costs for the control group during their initial ‘acute’ phase of illness. We concluded that the available cost estimates would need to be weighted to reflect the additional costs of drugs and investigations for this group of babies during the acute phase.

Multidisciplinary collaboration on trials can help economists and other researchers to balance the requirement for simple cost measurements with more detailed primary research.
Time preference, duration and health state valuations
Authors: Dolan Paul , Gudex Claire
Published: May 2012

There is increasing interest in health status measurement and the relative weights that people attach to different states of health and illness. One important issue which has been raised is the effect that the time spent in a health state may have on the way that state is perceived. Previous studies have suggested that the worse a state is, the more intolerable it becomes as it lasts longer. However, for most of these studies, it is impossible to determine how much of what was observed is attributable to the time spent in the state and how much is attributable to when it was occurring. This paper reports on a pilot study designed to test the feasibility of using the Time Trade‐Off (TTO) method to isolate the effect of pure time preference from the effect of duration per se. Interviews were conducted with 39 members of the general population who were asked to rate 5 health states for durations of one month, one year and ten years. In aggregate, rates of time preference were very close to zero which suggests that the implicit assumption of the TTO method that there is no discounting may be a valid one. However, that more respondents had negative (rather than positive) rates, casts some doubt on the axioms of discounted utility theory. In addition, implied valuations for states lasting for short periods were often counter‐intuitive which questions the feasibility of using the TTO method to measure preferences for temporary health states.
Are guidelines for peer‐reviewing economic evaluations necessary? A survey of current editorial practice
Authors: Jefferson Tom , Demicheli Vittorio
Published: May 2012

We report the results of a postal survey of 150 editors of medical journals aimed at assessing editorial policy on peer‐review of economic studies. 70 editors (47%) responded to the anonymous questionnaire which contained six questions. 16 (23% or respondents) claimed to have an editorial policy, most claiming acceptance of ‘good evaluations’. Few (36%) had trained economists as referees and none had criteria or guidelines for peer‐reviewing economic studies. This situation helps to explain the variable quality of international economic literature. There is an urgent need to produce internationally accepted sets of guidelines for authors, editors and peer‐reviewers.
Performance of Belgian hospitals: A frontier approach
Authors: Bosmans Nathalie , Fecher Fabienne
Published: May 2012

The purpose of the paper is to measure and to compare performance of Belgian hospitals during the year 1991. In order to measure hospitals' efficiency, we estimate a resource function which is defined as the relationship between medical fees incurred in the treatment of a patient and the patient's pathology. From this relation, we construct a best practice reference frontier which defines the minimal hospital medical fees needed to treat the pathology. Efficiency is assessed relative to this resource frontier using a parametric stochastic method proposed by Schmidt and Sickles.9

It appears that some specializations (circulatory system) involve more overproduction than others. Among the other results, we note that public hospitals are more efficient than the private ones and that university hospitals tend to use more resources than regular hospitals. The relationships between efficiency and different variables (location, size, costs and management) are finally analysed.
Willingness to pay for antenatal carrier screening for cystic fibrosis
Authors: Donaldson Cam , Shackley Phil , Abdalla Mona , Miedzybrodzka Zosia
Published: May 2012

We report on a study of women's willingness to pay (WTP) for a cystic fibrosis carrier test by one or other method of service delivery (disclosure or non‐disclosure). The results demonstrate that there was no statistically significant difference in WTP for the methods of testing. Those women who received a negative test result were followed up and asked their WTP for such a result. Values obtained at this stage were 16 per cent higher than those obtained pretest result. Use of prompts, rather than simply asking women to state their WTP, had a statistically significant effect on post‐test result values. The opportunity to terminate the pregnancy, if a test proved positive, was important, but was not the only consideration. This demonstrates the importance to women of other benefits of screening.
Investigating hospital efficiency in the new NHS: The role of the translog cost function
Authors: Scott Anthony , Parkin David
Published: May 2012

The reforms to the United Kingdom's National Health Service (NHS) of recent years have greatly increased the role of economic incentives in the hospital sector. Hospitals now have to compete for the business of GP and health authority purchasers and are assumed to have an incentive to minimise costs. This makes the analysis of cost functions much more relevant than has previously been the case. The objective of this paper is to assess the potential usefulness of the translog cost function applied in the NHS internal market. Three main issues are identified that limit the role of this type of cost function in the internal market: the adequacy of the econometric model (including data quality); the assumptions underlying the model, and; the interpretation of economies of scale, marginal costs and economies of scope that can be derived from such a cost function. It is concluded that at present the application of translog cost function analysis in the NHS is of limited usefulness, but that it does indicate areas for further methodological research.
The Effect of Mixed American–Chinese Group Composition on Computer‐Mediated Group Decision Making
Authors: Li Hui , Rau Pei‐Luen Patrick , Salvendy Gavriel
Published: May 2012

The objective of this study was to investigate the influences of cultural diversity and group composition on computer‐mediated group decision making for mixed American–Chinese groups. Seventy‐five Chinese and fifty Americans participated in a laboratory experiment. Twenty‐five five‐person groups were formed. Each group performed four preference decision‐making tasks with different levels of impact and complexity. Group‐level measurements of group outcomes and individual‐level measurements of group processes were collected. The results indicated that cultural diversity had both positive and negative effects on group decision making. Culturally heterogeneous groups made better decisions than did culturally homogeneous groups, but took longer to make decisions. Moreover, in terms of improvement of the quality of decisions, groups with a balanced representation from each culture outperformed unbalanced groups. Meanwhile, participants in the balanced groups had greater sensitivity to leader emergence and perceived less conflict. The results of this study also revealed the effects of self‐construal and self‐efficacy in communication on group performance. Implications for intercultural management were provided. © 2012 Wiley Periodicals, Inc.
A two‐dimensional model of hydraulic performance of stormwater infiltration systems
Authors: Browne D. , Deletic A. , Mudd G. M. , Fletcher T. D.
Published: May 2012

Stormwater infiltration systems are a popular method for urban stormwater control. They are often designed using an assumption of one‐dimensional saturated outflow, although this is not very accurate for many typical designs where two‐dimensional (2D) flows into unsaturated soils occur. Available 2D variably saturated flow models are not commonly used for design because of their complexity and difficulties with the required boundary conditions. A purpose‐built stormwater infiltration system model was thus developed for the simulation of 2D flow from a porous storage. The model combines a soil moisture–based model for unsaturated soils with a ponded storage model and uses a wetting front‐tracking approach for saturated flows. The model represents the main physical processes while minimizing input data requirements. The model was calibrated and validated using data from laboratory 2D stormwater infiltration trench experiments. Calibrations were undertaken using five different combinations of calibration data to examine calibration data requirements. It was found that storage water levels could be satisfactorily predicted using parameters calibrated with either data from laboratory soils tests or observed water level data, whereas the prediction of soil moistures was improved through the addition of observed soil moisture data to the calibration data set. Copyright © 2012 John Wiley & Sons, Ltd.
Anticipating the effects of groundwater withdrawal on seawater intrusion and soil settlement in urban coastal areas
Authors: Mas‐Pla Josep , Rodríguez‐Florit Agustí , Zamorano Manel , Roqué Carles , Menció Anna , Brusi David
Published: May 2012

Intensive pumping in urban coastal areas is a common threat to water resource quality due to seawater intrusion. In those areas where subsurface water resources are not usually used for human consumption or irrigation, intensive pumping is associated with other activities like the lowering of the water table necessary to support underground structures and building foundations. This activity also increases the likelihood of soil settlement that affects building stability and the corrosion of concrete structures due to groundwater salinity. Under these circumstances, the awareness of a certain municipality (Calonge, NE Spain) of the potential effects of groundwater withdrawal upon foundations has led to an integrated approach to anticipate seawater intrusion related to urban development. Geological mapping and correlation of borehole logs, electrical resistivity tomography, and hydrochemical data provide comprehensive knowledge of the geology and hydrogeology of the area and act as screening tools necessary to discern the influence of hydrological processes in coastal areas. Developing Strack's analytical solution, new comprehensive, dimensionless expressions are herein derived to determine the critical pumping rate necessary to prevent seawater intrusion, as well as to reproduce the evolution of the wedge toe and the water table stagnation point under different withdrawal rates. Furthermore, the Dupuit–Forchheimer well discharge formula allows the estimation of the effects of the water table lowering due to such critical pumping in the surrounding building foundations. Field data from the Calonge coastal plain illustrate this approach and provide assessment criteria for future urban development and planning. Copyright © 2012 John Wiley & Sons, Ltd.
Regional impacts of climate change on irrigation water demands
Authors: Rehana S. , Mujumdar P. P.
Published: May 2012

This paper presents an approach to model the expected impacts of climate change on irrigation water demand in a reservoir command area. A statistical downscaling model and an evapotranspiration model are used with a general circulation model (GCM) output to predict the anticipated change in the monthly irrigation water requirement of a crop. Specifically, we quantify the likely changes in irrigation water demands at a location in the command area, as a response to the projected changes in precipitation and evapotranspiration at that location. Statistical downscaling with a canonical correlation analysis is carried out to develop the future scenarios of meteorological variables (rainfall, relative humidity (RH), wind speed (U2), radiation, maximum (Tmax) and minimum (Tmin) temperatures) starting with simulations provided by a GCM for a specified emission scenario. The medium resolution Model for Interdisciplinary Research on Climate GCM is used with the A1B scenario, to assess the likely changes in irrigation demands for paddy, sugarcane, permanent garden and semidry crops over the command area of Bhadra reservoir, India.

Results from the downscaling model suggest that the monthly rainfall is likely to increase in the reservoir command area. RH, Tmax and Tmin are also projected to increase with small changes in U2. Consequently, the reference evapotranspiration, modeled by the Penman–Monteith equation, is predicted to increase. The irrigation requirements are assessed on monthly scale at nine selected locations encompassing the Bhadra reservoir command area. The irrigation requirements are projected to increase, in most cases, suggesting that the effect of projected increase in rainfall on the irrigation demands is offset by the effect due to projected increase/change in other meteorological variables (viz., Tmax and Tmin, solar radiation, RH and U2). The irrigation demand assessment study carried out at a river basin will be useful for future irrigation management systems. Copyright © 2012 John Wiley & Sons, Ltd.
Monitoring the melt season length of the Barnes Ice Cap over the 1979–2010 period using active and passive microwave remote sensing data
Authors: Dupont Florent , Royer Alain , Langlois Alexandre , Gressent Alicia , Picard Ghislain , Fily Michel , Cliche Patrick , Chum Miroslav
Published: May 2012

The Barnes Ice Cap (BIC) located on Baffin Island (Nunavut, Canada) is one of the most southern ice caps of the Canadian Arctic Archipelago. Observational data provide evidence of increased melting, thinning and contour recession due to recent climate warming in the Arctic. The duration of the summer melt season for the BIC, over the period 1979–2010, was derived using a threshold algorithm for 19 GHz horizontal polarization brightness temperature data; the passive microwave satellite measurements included data from the quasi‐daily Scanning Multichannel Microwave Radiometer and the Special Sensor Microwave Imager. Our results show the melt season lengthened by 33% from 65.6 ± 6 days at the beginning of the period (1979–1987) to 87.1 ± 7.8 days towards the end (2002–2010). The interannual variations of the number of melt days were in agreement with those derived from active microwave backscatter data from the QuikSCAT scatterometer for the overlapping 2000–2009 period. In addition, elevation change data from the ICESat altimeter confirmed the thinning of the BIC at a mean rate of −0.75 m/year for the 2003–2009 period. For the 32‐year period that we analysed, correlations with summer and annual air temperature and annual sum of positive days were examined for both the North American Regional Reanalysis and the Clyde River Automatic Weather Station data. Correlations with land surface temperature data from MODIS were also examined over the last decade. The results of these investigations showed that these climate indicators did not adequately explain the observed melt variations for the BIC. Ground‐based snow and ice measurements collected near the BIC summit during a 10‐day field campaign in March 2011 provided insights onto the surface properties and confirm the relevance of the remote sensing invariant threshold algorithm used for melt detection. Copyright © 2012 John Wiley & Sons, Ltd.