bluuebunny/crossref_metadata_2025 huggingface dataset:
Visual function and quality of life in pseudophakic patients before and after capsulotomy
Authors: de Juan-Marcos Lourdes , Blanco-Blanco Juan F. , Hernández-Galilea Emiliano
Published: March 2012

Purpose.

To assess the correlation between visual acuity, visual function, and health-related quality of life before and after neodymium: YAG laser posterior capsulotomy.

Methods.

A total of 150 patients with posterior capsule opacification (PCO) were examined before and after capsulotomy. Ocular examination, visual acuity, patient reports of satisfaction with vision, and disease-specific (VF-14 Index of Visual Functions) and generic (EuroQol: EQ-5D) outcomes were measured at baseline and 3 weeks after treatment.

Results.

After capsulotomy, patients showed significant improvements in binocular visual acuity, VF-14 index, satisfaction with vision, and EQ-5D measures. The average gains in visual function and quality of life were apparent in groups with good visual outcome and poor visual outcome. The VF-14 score improvement was moderately correlated with the EuroQol Visual Analogue Scale score improvement, showing stronger correlations with changes in self-reported satisfaction with vision than did gains in binocular visual acuity.

Conclusions.

Measuring of the outcomes of capsulotomy by clinical indicators alone may underestimate the overall benefits of treatment. Visual acuity in conjunction with visual function and health-related quality of life questionnaires will likely prove to be better indicators of the need for and outcome of capsulotomy.
Preliminary Experience with a New Device for Delayed Sternal Closure Strategy in Cardiac Surgery
Authors: Santini Francesco , Onorati Francesco , Telesca Mariassunta , Faggian Giuseppe , Mazzucco Alessandro
Published: March 2012

Purpose:

Open chest management with delayed sternal closure (DSC) is a valuable strategy in the management of patients with postcardiotomy hemodynamic instability or severe coagulopathy The conventional extemporized material available for off-label sternal stenting however may limit its efficacy We evaluated outcomes of patients with refractory severe postcardiotomy cardiogenic shock (SPCCS) treated with DSC using a novel temporary sternal spreader (NTSS) which allows myocardial recovery by progressive controlled approximation of the sternal edges.

Methods:

Seven patients (4 male, mean age 66.5 ± 5 years) with refractory SPCCS showing acute hemodynamic instability at sternal closure, were implanted with the NTSS, consisting of stainless-steel branches linked to 2 diverging plates of polyether-ether ketone, whose progressive opening/closing mechanism can be controlled from outside the chest with a rotating steel wire. The sternal wound was closed by an elastic membrane to achieve a sterile field. Swan-Ganz monitoring was employed, and clinical outcomes evaluated.

Results:

The device was successfully implanted in all patients without device-related complications or failures. Progressive approximation of sternal edges, titrated on cardiac index values, was successfully completed allowing subsequent uneventful sternal closure in all. Mean time from SPCCS to sternal closure was 70 ± 21 hours. No patient developed infective complications or late hemodynamic instability after device removal and sternal closure. One patient (14%) died of multiorgan failure on postoperative day 9.

Conclusions:

Despite the limited number of patients enrolled, the NTSS proved safe and effective in allowing complete myocardial recovery after SPCCS, avoiding hemodynamic instability related to abrupt sternal closure, with no occurrence of infective complications.
E-learning modules supported by cooperative learning: Impact on Arabic language achievement among Qatar University students
Authors: Hassan Mahmood Ahmed , Fook Fong Soon
Published: April 2012

This research aimed to investigate the impact of e-learning supported by cooperative learning on students' achievement in the core Arabic language course (ARAB100) delivered through the Blackboard system at Qatar University, State of Qatar. The activity theory was the basis for the design of the study which employed a 2 × 2 quasi-experimental factorial design to investigate the interaction between the independent variables of the research: e-learning supported by cooperative learning (EL+CL) and e-learning not supported by cooperative learning (EL − CL) with gender as a moderator variable and achievement in the Arabic language as a dependent variable. An achievement test was developed and administered to a sample of 170 undergraduate students (85 male and 85 Female) majoring in different subjects from seven colleges of the University over a 10-week period. Analysis of the findings by the two-way ANCOVA procedure was used to examine the three postulated hypotheses. The findings of this study showed that students assigned to the e-learning modules supported by cooperative learning (EL+CL) mode attained significantly higher adjusted mean scores on Arabic language achievement than students working on the e-learning module that were not supported by the cooperative learning (EL − CL) mode. Male students attained significantly higher adjusted mean scores on the achievement test than females using the same modules. No significant interaction effect was detected between e-learning modes and gender on achievement. In conclusion, the principles of the activity theory need to be considered when designing e-learning modules supported by cooperative learning activities in order to promote Arabic language learning.
¿Qué haría yo si volviese a ser un extensionista ?
Authors: Lacki Polan
Published: March 2012

DOI: http://dx.doi.org/10.5377/calera.v10i15.672
Interfaz Gráfica Computacional para Destilación Multicomponente utilizando Métodos Cortos
Authors: Osorio Mirón A. , Domínguez Hernández G. , Sánchez Bazán I. , González Landero G. E. , Sánchez Bazán L. A. , Hernández Aguilar E.
Published: March 2012

En este trabajo, se elaboró una interfaz gráfica que determina por medio de simulación en estado estacionario el número de platos necesarios en el proceso de destilación multicomponente, así como la composición en el flujo de destilado y fondos de una torre de destilación utilizando métodos cortos. La interfaz gráfica de usuario, se construyó en el lenguaje de programación Python 2.5, permite presentar los datos de entrada y salida para el caso de columnas de destilación operando en régimen permanente. Los resultados del uso de la interfaz gráfica muestran una forma simple de realizar diseños preliminares de torres de destilación y su potencialidad como material de apoyo para el estudio y comprensión de conceptos básicos en destilación multicomponente. En un trabajo posterior se podrá visualizar el desempeño del modelo dinámico a través de perturbaciones programadas en las condiciones de operación.Palabras claves: destilación multicomponente, métodos cortos, interfaz gráfica de usuario, Phyton 2.5.DOI: http://dx.doi.org/10.5377/nexo.v24i2.660
A Note on Exact Travelling Wave Solutions for the Klein–Gordon– Zakharov Equations
Authors: Zhang Zai-Yun , Zhang Ying-Hui , Gan Xiang-Yang , Yu De-Ming
Published: April 2012

16

In this paper, we investigate the travelling wave solutions for the Klein-Gordon-Zakharov equations by using the modified trigonometric function series method benefited to the ideas of Z. Y. Zhang, Y. X. Li, Z. H. Liu, and X. J. Miao, Commun. Nonlin. Sci. Numer. Simul. , 3097 (2011). Exact travelling wave solutions are obtained
Aplicação do Gerenciamento de Projetos no Processo de Desenvolvimento de Novos Produtos – Um Caso Exploratório
Authors: Almeida Leandro , Cauchick Miguel Paulo , Monteiro de Carvalho Marly
Published: March 2012

Projetos têm sido freqüentemente utilizados como forma de realização do plano estratégico das empresas. Um dos tipos de projetos é voltado para o desenvolvimento de novos produtos. Além de ser um elemento fundamental da estratégia das empresas e ser extremamente importante para a sua sobrevivência no longo-prazo, representa um dos mais arriscados empreendimentos das modernas corporações. Considerando estes argumentos, o uso de ferramentas e técnicas que auxiliem o seu gerenciamento é crucial. Nesse sentido, esse trabalho tem como objetivo demonstrar algumas das práticas de gerenciamento de projetos em um processo de desenvolvimento de novos produtos (PDP). Por meio de uma análise teórica das ferramentas e técnicas, o trabalho sugere uma forma abordar sua inserção no PDP. O estudo de caso consistiu de uma análise empírica da utilização dessas práticas no PDP de duas unidades de uma empresa do setor aeroespacial. A partir de uma análise teórica seguida de uma análise empírica, pode-se concluir que, apesar de grande parte das ferramentas citadas serem usadas para gerenciamento do desenvolvimento de produto, somente um terço delas são utilizadas de modo formal, o que pode acarretar em falta de um padrão para o gerenciamento e falta de entendimento comum no desenvolvimento de produto.DOI:10.5585/gep.v2i2.44
Riscos em Projetos de Docagem de Navios Petroleiros
Authors: Modica Jose Eduardo
Published: March 2012

A alta competitividade das empresas, em especial do setor de petróleo, tem obrigado as organizações a melhorar cada vez mais a sua gestão estratégica, incluindo a gestão dos seus portfólios de projetos bem como o gerenciamento de cada projeto dessas carteiras. Empresas transportadoras de petróleo e seus derivados, que operam navios petroleiros são obrigadas, por força de lei, a rotineiramente retirar seus navios de atividade para efetuar manutenções em operações conhecidas como docagens. Este artigo mostra uma pesquisa realizada em uma grande empresa brasileira transportadora de petróleo e seus derivados, para identificar os principais riscos gerenciais associados aos projetos de docagens de navios petroleiros.DOI:10.5585/gep.v2i2.52
CCSSM: Teaching in Grades 3 and 4
Authors: Barlow Angela T. , Harmon Shannon
Published: March 2012

To support mathematics educators as they consider the implications of the Common Core State Standards for Mathematics (CCSSM) on instruction and assessment, Teaching Children Mathematics is publishing a series of articles. In this third feature of the series, authors Barlow and Harmon suggest implementation strategies for grades 3 and 4. The next article covers additional topics, ideas, and commentary addressing grades 5 and 6.
Entrer dans la mer : post-humanité et dissolution du moi
Authors: Coulombe Maxime
Published: April 2012

L’art post-humain est l’histoire d’une rencontre : il tente de faire dialoguer, sous le régime de l’art, une certaine conception de l’homme et du corps avec les nouvelles technologies. L’imaginaire post-humain n’est aussi fascinant, aussi séduisant, que parce qu’il se propose de résoudre l’incomplétude coextensive à la condition humaine. En cela, nous aborderons ici la post-humanité comme une nouvelle foi souhaitant refonder un nouveau mode d’être au monde où le sujet pourrait se passer de toute altérité. À travers l’analyse de la production artistique de Stelarc, nous verrons que la post-humanité n’est pas simple science-fiction ; si elle est fiction, c’est qu’elle est de même une réponse, se voulant scientifique, à un désir de transcendance. En cela, l’art post-humain se fait à la fois symptôme – et par là voie d’analyse – de ces enjeux de sens et lieu d’exploration des promesses post-humaines.
Emphatic Italics in English Translations: Stylistic Failure or Motivated Stylistic Resources?
Authors: Saldanha Gabriela
Published: April 2012

This article argues that emphatic italics, a typographic feature regularly ignored by linguists and associated with poor style, have an important stylistic function in English, often working in implicit association with prosodic patterns in spoken language to signal marked information focus, thus fulfilling an important role in information structure and adding a conversational and involved tone to written texts. Emphatic italics are more common in English than in other languages because tonic prominence is the preferred means of marking information focus in English, while other languages use purely linguistic devices, such as word order. Thus arises the question of what happens in English translations from and into other languages. The study presented here looks at results obtained from a bidirectional English-Portuguese corpus (COMPARA) which suggest that italics may be less common in English translations from Portuguese than in non-translated English texts. This trend could potentially be explained by the use of common features of translated language, in particular explicitation and conservatism (also known as normalization). However, a closer look at the work of particular translators shows that the avoidance or use of italics is not a consistent feature of translations and may be a characteristic feature of the stylistic profile of certain translators.
The Shifting of the Demonstrative Determiner in French and Dutch in Parallel Corpora: From Translation Mechanisms to Structural Differences
Authors: Vanderbauwhede Gudrun , Desmet Piet , Lauwers Peter
Published: April 2012

This paper focuses on translational shifts with respect to the demonstrative determiner in French and Dutch in parallel corpora. The paper aims to identify the types of translation shifts that occur systematically, and to explore the underlying mechanisms and semantic effects of this process. For this purpose, a well-balanced sub-corpus of the Dutch Parallel Corpus is used, making it possible to analyze both directions (French – Dutch and Dutch – French). In this corpus, 50% of the demonstrative determiners are translated by a demonstrative in the target text (in both directions). In 20% of the cases, the demonstrative is translated by a definite article, or vice versa, while 30% are translated by another grammatical element (e.g., indefinite determiner, adverb, personal pronoun) or vice versa. The parallel corpus study reveals that translational shifts with respect to French and Dutch demonstratives can be attributed to three different mechanisms: (1) translator preference related to translation universals at the level of the noun phrase (omissions, additions and reformulations of the noun phrase), (2) specific manifestations of translation universals within the noun phrase (syntagmatic and paradigmatic explicitation and implicitation involving demonstrative shifting) and (3) structural divergences between the French and Dutch demonstrative determiner systems (fixed expressions and semantic differences). This analysis demonstrates the usefulness of a detailed parallel corpus study, which clearly distinguishes between changes occurring at different levels, in accounting for divergent translations of the demonstrative determiner in different languages. To this end, several types of explanation drawn from various fields (such as translation studies and contrastive linguistics), must be considered.
Transformations and Tactics
Authors: J. Martin Sylvia
Published: March 2012

This chapter examines the production culture of the film industry of Hong Kong after its 1997 return to China. Drawing from anthropological fieldwork, I posit that the production culture cannot be separated from the larger cultural practices and social formations in which it occurs. Three recurring themes within the film community are examined: decline, flexibility, and marginal social status. The reasons for the industry's decline are explicated through an analysis of how flexibility is employed as a tactic by industry members, particularly for Chinese co‐productions. I argue that the vaunted flexibility of the film industry is influenced by colonial and postcolonial discourse about entrepreneurship and neoliberalism and has in fact fragmented the collective power of Hong Kong film labor. Finally, I explore the industry's socially marginal status and illustrate the tactics deployed to transform the industry. These three themes illustrate the Hong Kong film industry's changing context within East Asia.
Supervisory control of uncertain systems with quantized information
Authors: Vu Linh , Liberzon Daniel
Published: March 2012

This work addresses the problem of stabilizing uncertain systems with quantized outputs using the supervisory control framework, in which a finite family of candidate controllers is employed together with an estimator‐based switching logic to select the active controller at every time. For static quantizers, we provide a relationship between the quantization range and the quantization error bound that guarantees closed‐loop stability. Such a condition also implies a lower bound on the number of information bits needed to guarantee stability of a supervisory control scheme with quantized information. For dynamic quantizers that can vary the quantization parameters in real time, we show that the closed loop can be asymptotically stabilized, provided that additional conditions on the quantization range and the quantization error bound are satisfied. Copyright © 2012 John Wiley & Sons, Ltd.
A signal processing adaptive algorithm for nonstationary power signal parameter estimation
Authors: Hasan Shazia , Dash P.K. , Nanda S.
Published: March 2012

This paper presents the design and analysis of an adaptive algorithm for tracking the amplitude, phase and frequency of the fundamental, harmonics and interharmonics present in time‐varying power sinusoid in white noise. If frequency, amplitude and phase of the multiple sinusoids become nonstationary, they are estimated as an unconstrained optimization problem using robust and low complexity multi‐objective Gauss–Newton algorithm. The presented algorithm deals with frequency drift and can accurately estimate frequency variation, amplitude and phase variation, as well as harmonic amplitude and phase variations. Further, the learning parameters in the proposed algorithm are tuned iteratively to provide faster convergence and better accuracy. The excellent tracking capability of proposed multi‐objective Gauss–Newton algorithm is shown through simulation and experimental results in a nonstationary environment. Copyright © 2012 John Wiley & Sons, Ltd.
Halogen Bonding versus Hydrogen Bonding in Driving Self‐Assembly and Performance of Light‐Responsive Supramolecular Polymers
Authors: Priimagi Arri , Cavallo Gabriella , Forni Alessandra , Gorynsztejn–Leben Mikael , Kaivola Matti , Metrangolo Pierangelo , Milani Roberto , Shishido Atsushi , Pilati Tullio , Resnati Giuseppe , Terraneo Giancarlo
Published: March 2012

Halogen bonding is arguably the least exploited among the many non‐covalent interactions used in dictating molecular self‐assembly. However, its directionality renders it unique compared to ubiquitous hydrogen bonding. Here, the role of this directionality in controlling the performance of light‐responsive supramolecular polymers is highlighted. In particular, it is shown that light‐induced surface patterning, a unique phenomenon occurring in azobenzene‐containing polymers, is more efficient in halogen‐bonded polymer–azobenzene complexes than in the analogous hydrogen‐bonded complexes. A systematic study is performed on a series of azo dyes containing different halogen or hydrogen bonding donor moieties, complexed to poly(4‐vinylpyridine) backbone. Through single‐atom substitution of the bond‐donor, control of both the strength and the nature of the noncovalent interaction between the azobenzene units and the polymer backbone is achieved. Importantly, such substitution does not significantly alter the electronic properties of the azobenzene units, hence providing us with unique tools in studying the structure–performance relationships in the light‐induced surface deformation process. The results represent the first demonstration of light‐responsive halogen‐bonded polymer systems and also highlight the remarkable potential of halogen bonding in fundamental studies of photoresponsive azobenzene‐containing polymers.
Estrogenic plant foods of red colobus monkeys and mountain gorillas in uganda
Authors: Wasserman Michael D. , Taylor‐Gutt Alexandra , Rothman Jessica M. , Chapman Colin A. , Milton Katharine , Leitman Dale C.
Published: March 2012

Phytoestrogens, or naturally occurring estrogen‐mimicking compounds, are found in many human plant foods, such as soybeans (Glycine max) and other legumes. Because the consumption of phytoestrogens may result in both health benefits of protecting against estrogen‐dependent cancers and reproductive costs of disrupting the developing endocrine system, considerable biomedical research has been focused on the physiological and behavioral effects of these compounds. Despite this interest, little is known about the occurrence of phytoestrogens in the diets of wild primates, nor their likely evolutionary importance. We investigated the prevalence of estrogenic plant foods in the diets of two folivorous primate species, the red colobus monkey (Procolobus rufomitratus) of Kibale National Park and mountain gorilla (Gorilla beringei) of Bwindi Impenetrable National Park, both in Uganda. To examine plant foods for estrogenic activity, we screened 44 plant items (species and part) comprising 78.4% of the diet of red colobus monkeys and 53 plant items comprising 85.2% of the diet of mountain gorillas using transient transfection assays. At least 10.6% of the red colobus diet and 8.8% of the gorilla diet had estrogenic activity. This was mainly the result of the red colobus eating three estrogenic staple foods and the gorillas eating one estrogenic staple food. All estrogenic plants exhibited estrogen receptor (ER) subtype selectivity, as their phytoestrogens activated ERβ, but not ERα. These results demonstrate that estrogenic plant foods are routinely consumed by two folivorous primate species. Phytoestrogens in the wild plant foods of these two species and many other wild primates may have important implications for understanding primate reproductive ecology. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.
Application and performance of maleated thermoplastic starch–poly(butylene adipate‐co‐terephthalate) blends for films
Authors: Stagner Jacqueline A. , Alves Vanessa Dias , Narayan Ramani
Published: March 2012

In this work, we studied the effect of the percentage of maleated thermoplastic starch (MTPS) in MTPS–poly(butylene adipate‐co‐terephthalate) (PBAT) blends that were used to produce extruded films. The materials were characterized by their mechanical properties (tensile and puncture tests), their barrier properties (carbon dioxide, oxygen, and water‐vapor permeability tests), and microstructural analysis [transmission electron microscopy (TEM)], and the biobased content of the materials was determined. The results of the testing show that increasing the MTPS content decreased the tensile strength (from 19.7 to 8.6 MPa in the machine direction and from 15.3 to 7.1 MPa in the transverse direction) and puncture force (from 42.5 to 30.3 N) of the films; however, the elongation was not significantly affected. The permeability of the films to oxygen and carbon dioxide decreased with increasing MTPS content. The oxygen permeability decreased from 1.68 × 10−17 to 6.0 × 10−18 kg m m−2 s−1 Pa−1, whereas the carbon dioxide permeability decreased from 3.0 × 10−16 to 1.1 × 10−16 kg m m−2 s−1 Pa−1. However, the permeability to water vapor increased from 5.0 × 10−15 to 1.04 × 10−14 kg m m−2 s−1 Pa−1. Finally, TEM showed that PBAT was the continuous phase and MTPS was the dispersed phase. As the amount of MTPS in the samples increased, the dispersed phase became finer and more regularly spaced. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterizations of a latent polyhedral oligomeric silsequioxane‐containing catalyst and its application in polybenzoxazine resin
Authors: Wang Lei , Du Wenjie , Wu Yixian , Xu Riwei , Yu Dingsheng
Published: March 2012

In this article, a novel latent curing agent, octa(paratoluenesulfonic acid ammomium salt) (OPAAS) polyhedral oligomeric silsequioxane was synthesized and used in modifying the polybenzoxazine/2,2′‐(1,3‐phenylene)‐bis(4,5‐dihydro‐oxazoles) (PBO) (PBZ/PBO) resin. The liberated octa(aminophenyl) silsesquioxane and paratoluenesulfonic acid can catalyze the ring‐opening reaction of benzoxazine (BZ) resin. The initial curing temperature (Ti), peak curing temperature (Tp) and the Enthalpy of the curing temperature had significantly decreased with respect to pristine BZ/PBO resin. When the OPAAS amount was 3 wt %, the peak curing temperature decreased from 233.7 to 218.2°C. Also, PBZ/PBO/OPAAS composites exhibited better storage modulus than pure PBZ/PBO resin. Meanwhile, PBZ/PBO/OPAAS composites are more thermally stable than PBZ/PBO resin. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Plasma surface modification of porous PLLA films: Analysis of surface properties and in vitro hydrolytic degradation
Authors: Mattioli S. , Kenny J. M. , Armentano I.
Published: March 2012

The aim of this research was to investigate the effects of plasma treatment on the surface and on the in vitro degradation behavior of poly(L‐lactide) (PLLA) films. Polymer films were prepared by solvent casting, and their surface was modified by radiofrequency plasma treatments by using oxygen and tetrafluorocarbon gas. Pristine and treated PLLA films were characterized by field emission and atomic force microscopy and by contact angle measurements. In vitro hydrolytic degradation studies were conducted by measurements of weight loss, water absorption, visual inspection, and thermal transitions as a function of the incubation time. As‐deposited PLLA films show a uniform distribution of ring‐like porous structures on the surface due to solvent evaporation. Plasma treatments produce a mass reduction following the etching of the polymer surface. Moreover, the morphology of the porous polymer is modified by the plasma, which induces different micro/nanometric topographic reliefs as a function of the different selected plasma processing parameters. The results indicate PLLA surface become hydrophilic and the surface roughness increased with treatment time in the case of oxygen, whereas a hydrophobic behavior was induced with tetrafluorocarbon plasma treatment. However, in vitro degradation studies show that plasma treatments do not affect the PLLA bulk and the hydrolytic degradation properties. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Newly evolved genes: Moving from comparative genomics to functional studies in model systems
Authors: Ranz José M. , Parsch John
Published: March 2012

Genes are gained and lost over the course of evolution. A recent study found that over 1,800 new genes have appeared during primate evolution and that an unexpectedly high proportion of these genes are expressed in the human brain. But what are the molecular functions of newly evolved genes and what is their impact on an organism's fitness? The acquisition of new genes may provide a rich source of genetic diversity that fuels evolutionary innovation. Although gene manipulation experiments are not feasible in humans, studies in model organisms, such as Drosophila melanogaster, have shown that new genes can quickly become integrated into genetic networks and become essential for survival or fertility. Future studies of new genes, especially chimeric genes, and their functions will help determine the role of genetic novelty in the adaptation and diversification of species.
Reduced‐order modeling for cardiac electrophysiology. Application to parameter identification
Authors: Boulakia M. , Schenone E. , Gerbeau J‐F.
Published: March 2012

A reduced‐order model based on proper orthogonal decomposition (POD) is proposed for the bidomain equations of cardiac electrophysiology. Its accuracy is assessed through electrocardiograms in various configurations, including myocardium infarctions and long‐time simulations. We show in particular that a restitution curve can efficiently be approximated by this approach. The reduced‐order model is then used in an inverse problem solved by an evolutionary algorithm. Some attempts are presented to identify ionic parameters and infarction locations from synthetic electrocardiograms. Copyright © 2012 John Wiley & Sons, Ltd.
Smoothed particle hydrodynamics method applied to pulsatile flow inside a rigid two‐dimensional model of left heart cavity
Authors: Shahriari S. , Kadem L. , Rogers B.D. , Hassan I.
Published: March 2012

This paper aims to extend the application of smoothed particle hydrodynamics (SPH), a meshfree particle method, to simulate flow inside a model of the heart's left ventricle (LV). This work is considered the first attempt to simulate flow inside a heart cavity using a meshfree particle method. Simulating this kind of flow, characterized by high pulsatility and moderate Reynolds number using SPH is challenging. As a consequence, validation of the computational code using benchmark cases is required prior to simulating the flow inside a model of the LV. In this work, this is accomplished by simulating an unsteady oscillating flow (pressure amplitude: A = 2500 N ∕ m3 and Womersley number: Wo = 16) and the steady lid‐driven cavity flow (Re = 3200, 5000). The results are compared against analytical solutions and reference data to assess convergence. Then, both benchmark cases are combined and a pulsatile jet in a cavity is simulated and the results are compared with the finite volume method. Here, an approach to deal with inflow and outflow boundary conditions is introduced. Finally, pulsatile inlet flow in a rigid model of the LV is simulated. The results demonstrate the ability of SPH to model complex cardiovascular flows and to track the history of fluid properties. Some interesting features of SPH are also demonstrated in this study, including the relation between particle resolution and sound speed to control compressibility effects and also order of convergence in SPH simulations, which is consistently demonstrated to be between first‐order and second‐order at the moderate Reynolds numbers investigated. Copyright © 2012 John Wiley & Sons, Ltd.
Application‐driven analysis of two generations of capability computing: the transition to multicore processors
Authors: Rajan Mahesh , Vaughan Courtenay T. , Doerfler Doug W. , Barrett Richard F. , Lin Paul T. , Pedretti Kevin T. , Scott Hemmert K.
Published: March 2012

Multicore processors form the basis of most traditional high performance parallel processing architectures. Early experiences with these computers showed significant performance problems, both with regard to computation and inter‐process communication. The transition from Purple, an IBM POWER5‐based machine, to Cielo, a Cray XE6, as the main capability computing platform for the United States Department of Energy's Advanced Simulation and Computing campaign provides an opportunity to reexamine these issues after experiences with a few generations of multicore‐based machines. Experiences with Purple identified some important characteristics that led to strong performance of complex scientific application programs at very large scales. Herein, we compare the performance of some Advanced Simulation and Computing mission critical applications at capability scale across this transition to multicore processors. Copyright © 2012 John Wiley & Sons, Ltd.
Molecular MR Imaging of Collagen in Mouse Atherosclerosis by Using Paramagnetic CNA35 Micelles
Authors: van Bochove Glenda S. , Sanders Honorius M. H. F. , de Smet Mariska , Keizer Henk M. , Mulder Willem J. M. , Krams Rob , Strijkers Gustav J. , Nicolay Klaas
Published: March 2012

Magnetic resonance imaging (MRI) is increasingly used in biomedicine to visualize plaques in the walls of major arteries in relation to atherosclerosis, the prime cause of myocardial infarction and ischemic stroke. The present study aims to explore the utility of contrast‐enhanced MRI for improving the specificity of the MRI evaluation of atherosclerotic plaques with the use of a Gd‐based paramagnetic contrast agent that is targeted to collagen. Collagen is a major component of the extracellular matrix and as such plays an important role in the stability of atherosclerotic plaques. Micelles were made with lipid containing 45 mol‐% Gd for MRI detection and a low mol fraction of fluorescent lipid for fluorescence microscopic analysis. Collagen‐targeted, functional micelles were prepared by conjugation of the CNA35 protein, while nonfunctional control micelles were conjugated with a mutated version of the protein. The micelles were characterized with respect to their magnetic, biochemical, and biophysical properties. Atherosclerotic plaques were induced in the right carotid artery of apo‐E knock‐out mice by surgical placement of a tapered polymeric cast. In vivo MRI was performed at 6.3 Tesla before and up to 24 h after intravenous injection of paramagnetic micelles (50 μmol Gd kg–1). MRI revealed the strongest signal enhancements by CNA35 micelles. At early time points after injection of CNA35 micelles, contrast enhancement was higher in the collagen‐richer lesions compared to that in the collagen‐poorer lesions. Confocal laser scanning microscopy confirmed co‐localization of CNA35 micelles and collagen in the plaques. We have demonstrated molecular MR imaging of collagen in experimental atherosclerosis by using a CNA35‐functionalized micellar contrast agent.
Stereocontrol with Lithium Trimethylzincate toward Gibberellin Synthesis (Eur. J. Org. Chem. 11/2012)
Authors: Isobe Minoru , Chiang Ching‐Te , Tsao Kuo‐Wei , Cheng Chia‐Yi , Bruening Reimar
Published: March 2012

The cover picture shows the North Gate of Hsinchu City, Taiwan, which has been preserved as a historical heritage site of the city, surrounded by modern electronic devices. The molecules shown include the synthesis of the A‐ring substructure of gibberellin, a plant hormone. The key reaction, the ability of lithium trimethylzincate to undergo conjugate addition, as discovered in 1977, was developed for the synthesis of the A‐ring in collaboration with Dr. Reimar Bruening in Nagoya University around 1980 (unpublished). Now, in 2012, this zincate chemistry has been used as the indispensable step at National Tsing Hua University. Zinc chemistry is surrounded by modern synthetic devices. Details are presented in the Short Communication by M. Isobe et al. on p. 2109 ff. Chia‐Yi Cheng is acknowledged for her help in designing this cover picture.

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Path‐based Multipath Protection: resilience using multiple paths
Authors: Gyarmati László , Cinkler Tibor , Trinh Tuan Anh
Published: March 2012

The Multipath Protection (MPP) network resilience methods route and protect the upcoming demand over multiple paths. Although these schemes are able to allocate resources efficiently in the network, the length of the paths that the packets traverse cannot be controlled. Accordingly, to control the latency of the connections, we reuse the idea of MPP when we propose the Path‐based Multipath Protection (PMPP) scheme. By controlling the maximal length of the paths, we increase the availability as well, because on shorter paths, fewer failures happen. The contribution of our work is threefold. First, we give the linear programming formulation of the PMPP method that does not have any integer variables resulting from polynomial runtime, similar to the former MPP methods. Second, we present extensive simulation results including the blocking ratios, the properties of the paths and the availabilities. Finally, we compare the PMPP resilience scheme with the original and improved versions of MPP method on the basis of several metrics. Copyright © 2012 John Wiley & Sons, Ltd.
METHODS FOR COVARIATE ADJUSTMENT IN COST‐EFFECTIVENESS ANALYSIS THAT USE CLUSTER RANDOMISED TRIALS
Authors: Gomes Manuel , Grieve Richard , Nixon Richard , Ng Edmond S.‐W. , Carpenter James , Thompson Simon G.
Published: March 2012

Statistical methods have been developed for cost‐effectiveness analyses of cluster randomised trials (CRTs) where baseline covariates are balanced. However, CRTs may show systematic differences in individual and cluster‐level covariates between the treatment groups. This paper presents three methods to adjust for imbalances in observed covariates: seemingly unrelated regression with a robust standard error, a ‘two‐stage’ bootstrap approach combined with seemingly unrelated regression and multilevel models. We consider the methods in a cost‐effectiveness analysis of a CRT with covariate imbalance, unequal cluster sizes and a prognostic relationship that varied by treatment group. The cost‐effectiveness results differed according to the approach for covariate adjustment.

A simulation study then assessed the relative performance of methods for addressing systematic imbalance in baseline covariates. The simulations extended the case study and considered scenarios with different levels of confounding, cluster size variation and few clusters. Performance was reported as bias, root mean squared error and CI coverage of the incremental net benefit. Even with low levels of confounding, unadjusted methods were biased, but all adjusted methods were unbiased. Multilevel models performed well across all settings, and unlike the other methods, reported CI coverage close to nominal levels even with few clusters of unequal sizes. Copyright © 2012 John Wiley & Sons, Ltd.
Building ambidexterity: The role of human resource practices in the performance of firms from Spain
Authors: Prieto Isabel M. , Pilar Pérez Santana M.
Published: March 2012

Both researchers and managers are increasingly interested in how firms can pursue ambidextrous learning—that is, simultaneously exploring new knowledge domains while exploiting current ones. In this study, we attempt to bring human resource management into this forum by introducing and testing how high‐involvement human resource practices shape the social climate that affects the firm's ambidextrous learning and subsequent performance. A field study of 198 companies from Spain showed that high‐involvement human resource practices were positively related to the social climate that, in turn, facilitates ambidextrous learning and improved performance. © 2012 Wiley Periodicals, Inc.
Perceived training intensity and knowledge sharing: Sharing for intrinsic and prosocial reasons
Authors: Kuvaas Bård , Buch Robert , Dysvik Anders
Published: March 2012

This study investigated the relationship between perceived training intensity and knowledge sharing, including the moderating roles of intrinsic motivation and social and economic exchange perceptions. Data from 310 employees working in three organizations located in Norway revealed a positive relationship between perceived training intensity and knowledge sharing for employees with low levels of intrinsic motivation and economic exchange perception, and high levels of social exchange perception. These findings suggest that perceived training intensity increases knowledge sharing only under specific motivational influences. Implications for practice and directions for future research are discussed. © 2012 Wiley Periodicals, Inc
A weekly diary study on the buffering role of social support in the relationship between job insecurity and employee performance
Authors: Schreurs Bert H. J. , Hetty van Emmerik IJ. , Günter Hannes , Germeys Filip
Published: March 2012

In this article, the authors used a within‐person design to examine the relationship between job insecurity and employee in‐role and extra‐role performance, and the buffering role of time‐varying work‐based support (i.e., supervisor and colleague support) in this relationship. Weekly diary data gathered over the course of three weeks from 56 employees confronted with organizational restructuring and analyzed with a hierarchical linear modeling approach showed that weekly fluctuations in job insecurity negatively predicted week‐level in‐role performance. As predicted, supervisor support moderated the intra‐individual relationship between job insecurity and in‐role performance, so that employees' in‐role performance suffered less from feeling job insecurity during weeks in which they received more support from their supervisor. No relationship between job insecurity and extra‐role performance was observed. This within‐person study contributes to research on job insecurity that has primarily focused on inter‐individual differences in job insecurity and their associations with job performance. Theoretical and practical implications for human resource management are discussed. © 2012 Wiley Periodicals, Inc.
Non‐linear microscopy of smooth muscle cells in artificial extracellular matrices made of cellulose
Authors: Brackmann Christian , Dahlberg Jan‐Olof , Vrana Nihal Engin , Lally Caitriona , Gatenholm Paul , Enejder Annika
Published: March 2012

Non‐linear microscopy has been used to characterize bovine smooth muscle cells and their proliferation, migration, and differentiation in hydrogel cellulose scaffolds, toward the development of fully functional blood vessel implants. The extracellular matrix (ECM) composed of cellulose and endogenous collagen fibers was imaged using Second Harmonic Generation (SHG) microscopy and the cell morphology by Coherent Anti‐Stokes Raman Scattering (CARS) microscopy. Images prove that cells adhere on the cellulose scaffold without additional surface modification and that both contractile and proliferating phenotypes are developed. This work shows that non‐linear microscopy contributes with unique insights in cell interactions with (artificial) ECM components and has the potential to become an established characterization method in tissue engineering. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Segmentation and fusion on the midline: Basibranchial homologies in cypriniform fishes
Authors: Engeman Jeffrey M. , Mabee Paula M.
Published: March 2012

The development and homologies of the median elements of the ventral hyoid and branchial arches of Cypriniformes have been unclear. We compared the developmental morphology of this region across five species (Cycleptus elongatus, Luxilus zonatus, Danio rerio, Devario auropurpureus, and Cobitis striata), representing three of five major clades of cypriniforms. The development of basibranchial 1 is similar in catostomids and cyprinids, where a single, elongate, basihyal + anterior copula divides into separate elements. A gap develops between the posterior end of the basihyal cartilage and the anterior copula in catostomids but in cyprinids (Luxiluszonatus, Danio rerio, and Devarioauropurpureus) there is little separation and the basihyal and basibranchial 1 may grow close together or retain a cartilaginous connection (Danio rerio, several outgroups). In loaches and Gyrinocheilus, the gap posterior to the basihyal has been alternately interpreted as either the absence or posterior displacement of basibranchial 1. Uniquely among examined species, in Cobitis striata, the basihyal cartilage and anterior copula form as separate cartilages and remain distinct throughout development with a prominent gap between the basihyal and most anterior basibranchial, which we interpret as loss of basibranchial 1. In the posterior region associated with branchial arches 4 and 5, all examined species except Danio rerio, which has only a basibranchial 4 cartilage, have separate basibranchial 4 and 5 cartilages in early ontogeny. Basibranchials 4 and 5 remain separate in Cycleptus elongatus, Devario auropurpurea, and Cobitis striata, but fuse in Luxilus zonatus to form a posterior copula. The orientation of basibranchial 4 and 5 cartilages in Cobitis striata is similar to catostomids and cyprinids. The most posterior median element in the branchial arches, the post‐ceratobranchial cartilage, generally forms as a separate cartilage in catostomids but in Cobitis striata is connected with basibranchial 5 cartilage from earliest appearance. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.
Ontogenetic influence on neural spine bifurcation in diplodocoidea (dinosauria: Sauropoda): A critical phylogenetic character
Authors: Woodruff D. Cary , Fowler Denver W.
Published: March 2012

Within Diplodocoidea (Dinosauria: Sauropoda), phylogenetic position of the three subclades Rebbachisauridae, Dicraeosauridae, and Diplodocidae is strongly influenced by a relatively small number of characters. Neural spine bifurcation, especially within the cervical vertebrae, is considered to be a derived character, with taxa that lack this feature regarded as relatively basal. Our analysis of dorsal and cervical vertebrae from small‐sized diplodocoids (representing at least 18 individuals) reveals that neural spine bifurcation is less well developed or absent in smaller specimens. New preparation of the roughly 200‐cm long diplodocid juvenile Sauriermuseum Aathal 0009 reveals simple nonbifurcated cervical neural spines, strongly reminiscent of more basal sauropods such as Omeisaurus. An identical pattern of ontogenetically linked bifurcation has also been observed in several specimens of the basal macronarian Camarasaurus, suggesting that this is characteristic of several clades of Sauropoda. We suggest that neural spine bifurcation performs a biomechanical function related to horizontal positioning of the neck that may become significant only at the onset of a larger body size, hence, its apparent absence or weaker development in smaller specimens. These results have significant implications for the taxonomy and phylogenetic position of taxa described from specimens of small body size. On the basis of shallow bifurcation of its cervical and dorsal neural spines, the small diplodocid Suuwassea is more parsimoniously interpreted as an immature specimen of an already recognized diplodocid taxon. Our findings emphasize the view that nonmature dinosaurs often exhibit morphologies more similar to their ancestral state and may therefore occupy a more basal position in phylogenetic analyses than would mature specimens of the same species. In light of this, we stress the need for phylogenetic reanalysis of sauropod clades where vital characters may be ontogenetically variable, particularly when data is derived from small individuals. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.
A note on optimal allocations for the second elementary symmetric function with applications for optimal reliability design
Authors: Peng Chien‐Yu
Published: March 2012

This article considers the problem of determining the optimal size allocation and optimal number of experimental conditions for a second elementary symmetric function with different coefficients. Analytical solutions for several practical applications are derived and the general formulation is used to elucidate the foundation between different parametric models found in recent studies. A geometrical interpretation of the structure of some theoretical results is also provided. This approach renders some complex problems more tractable than what numerical search algorithms would allow. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012
Nonlinear observers for a class of nonlinear descriptor systems
Authors: Yang Chunyu , Zhang Qingling , Chai Tianyou
Published: March 2012

This paper considers a class of nonlinear descriptor systems whose nonlinear terms are time‐varying and satisfy a quadratic inequality. An nonlinear observer is constructed and the error system is represented by a Lur'e descriptor system (LDS). Motivated by the basic idea of absolute stability theory, both types of full‐order and reduced‐order observers are constructed by a unified approach. The proposed method generalizes the existing ones for standard state‐space systems, and global convergence of the nonlinear observer is achieved without the usual global Lipschitz restriction. Furthermore, the stability criterion for the error system extends the existing ones for LDS in the sense that the involved interconnected nonlinearities are time‐varying and in unbounded sector. Finally, the design methods are reduced to a linear matrix inequality problem and illustrated by two numerical examples. Copyright © 2012 John Wiley & Sons, Ltd.