bluuebunny/crossref_metadata_2025 huggingface dataset:
Dependence of the moduli of random bimodal networks on chain‐length distribution
Authors: Sharaf M. A. , Mark J. E.
Published: March 2011

There have now been a number of experimental studies on the preparation and elastomeric properties of random bimodal networks of polydimethylsiloxane. The mole per cent of the short chains and their molecular masses covered a wide range, thus resulting in various polydisperse chain‐length distributions. The networks were studied with regard to their stress‐strain isotherms in elongation, and values of their moduli in the large‐deformation (phantom) limit were found to depend on the chain‐length distribution. This Important result is in disagreement with phantom network theory, which assumes the elastic modulus is dependent only on the mean value of chain lengths such that the cycle rank of the network is preserved. The effective functionality of the long chains was found to depend on the number of short chains present. Better agreement with experiment was obtained when account was taken of the connectivity of the very short chains, in what is essentially a bimodal distribution of both network chain lengths and cross‐link functionalities. Relevant here is the fact that as the degree of chemical cross‐linking Increases, the shear modulus G moves away from the affine limit, toward the phantom limit. This increase toward phantom behavior is presumably due to the fact that the mutual interspersion of chains is less when the chains are shorter, even in the small‐strain region.
Characterization and gel point of randomly linked high cis‐polybutadiene networks
Authors: Pyckhout‐Hintzen W. , Müller B. , Springer T.
Published: March 2011

Cis—Polybutadiene networks (98% cis), crosslinked in the bulk state by gamma irradiation were characterized in terms of their mechanical properties. Data from stress‐strain analyses, swelling degrees, stress relaxation and random—linking theory are in accordance and the estimated gel points practically coincide. Trapped entanglements contributed up to 30% to the network modulus, from which also the plateau modulus was determined. The tensile data were obtained from Mooney—Rivlin representations. It was concluded that the assumption of additive contributions from chemical and entanglement crosslink densities in the Langley theory works well in the range of doses investigated here. A comparison with a tube—like approach of these networks is made.
Influence of the dispersed phase upon the behaviour of nylon/rubber blends; crosslinking effect
Authors: Seo Yongsok
Published: March 2011

Nylon 6 and crosslinked SBS rubber blends were prepared. Their impact strength tests demonstrated the possibility of the existence of a maximum in impact strength at a moderate degree of crosslinking level. However, its peak value was not so much eminent as that happened in tensile test or brittle polymer's impact test. This seems due to complex mechanism occurred in dispersed phase. Based on our experimental data, we believe cavitation is important in nylon toughening. Interpretation of nylon toughening mechanism by cavitation and particle deformation is suggested for the reason of low peak value. Even though delamination is also possible, tensile strength data support cavitation in the rubber particle which seems to be more plausible for toughened nylon 6.
Critical behavior of trifunctional randomly branched polycyanurates
Authors: Bauer Jörg , Burchard Walther
Published: March 2011

The behavior near the gelation threshold of trifunctional randomly branched polycyanurates is studied by static and dynamic light scattering. By static measurements the critical exponents γ, σ and η were obtained, which describe the divergence of the weight average (Mw) and the cutoff (M*) molecular weights and the radius of gyration (Rg) respectively. All these independently measured exponents together with τ, characterizing the power law behavior of the molecular weight distribution and measured by size exclusion chromatography coupled with light scattering, confirm the predictions of the three‐dimensional percolation theory. With the help of size exclusion chromatography coupled with a light scattering and a viscosity detector, a fractal dimension D = 2.24 is obtained. On the other side, from the corresponding exponent for the whole unfractionated samples a fractal dimension D = 2.21 results, using a theory of Daoud. This suggests that the fractal dimension of the polycyanurates in dilute solution lies between the theoretical predictions D = 2.5 for the unswollen and D = 2.0 for the completely swollen state. Furthermore, it is shown by dynamic light scattering that the power law behavior over some decades in time of the time autocorrelation function and the divergence of the mean relaxation time are characteristics of the gelpoint. The development with increasing reaction time of the time correlation function of the gelling system from the pregel through the gelpoint into the gel state is analyzed quantitatively by a hybrid of a stretched exponential and a power law function.
Randomly branched polycyanurates ‐ modification of the network structure
Authors: Bauer Monika , Bauer Jörg
Published: March 2011

Polycyanurates (poly(2,4,6‐trisaroxy‐1,3,5‐triazines)) are built up through a step‐growth polycyclotrimerization of difunctional aromatic cyanic acid esters and form an ideally trifunctional randomly branched network, where all initial cyanato groups are linked with the triazine branching units at full conversion. Results on modifications of the high network density of pure polycyanurates are reported for three types of comonomers: monofunctional cyanic acid esters, difunctional phenols and difunctional aromatic glycidyl ethers. Using the coreaction of mono‐ and difunctional aromatic cyanic acid esters, additional chain segments, dangling ends and low molecular weight compounds are built, the fractions of which are dependent on the initial admixture of the monofunctional compound and its relative reactivity. Therefore, the critical conversion at the gel point is shifted to higher values and the network density at full conversion decreases. The abstraction of phenols from intermediately formed iminocarbonic ester structures is utilized for the modification of the polycyanurate network through the coreaction of difunctional aromatic cyanic acid esters with phenols. It was found that the critical conversion and the network structure are dependent on all the initial amount of phenols, their reactivity and functionality. The modification with the help of glycidyl ethers is characterized by an insertion of the oxirane ring into the cyanurate and the succeeding reactions into isocyanurates and oxazolidinones. Depending on the initial mixture and the reaction conditions, a large spectrum of chemical and topological network structures can be obtained, what is demonstrated by both experimental and theoretical investigations.
Novel macromolecular architectures: Globular block copolymers containing dendritic components
Authors: Hawker Craig J. , Wooley Karen L. , Fréchet Jean M. J.
Published: March 2011

The synthesis of three different macromolecular architectures, dendritic segment‐block, layer‐block, and surface‐block copolymers, all of which can be regarded as new types of block copolymers, is discussed. The factors determining the physical properties of each of these unusual materials are studied and related to the dendritic structure.
Preparation of crystalline and solvent resistant polycarbonates via ring‐opening polymerization of cyclic oligomers
Authors: Brunelle Daniel J. , Krabbenhoft Herman O. , Bonauto David K.
Published: March 2011

A route to solvent‐resistant polycarbonates which may also be crystalline has been achieved through the intermediacy of cyclic oligomeric carbonates. Mixed oligomeric cyclics of a variety of bisphenols were prepared via the carefully controlled hydrolysis‐condensation of their bischloroformates. Following ring‐opening polymerization, the polymers were evaluated for potential solvent resistance. Copolymers of hydroquinone and bisphenol A containing ratios of hydroquinone to BPA between 50/50 and 70/30 were found to be insoluble in CH2Cl2, tetrahydrofuran, and CHCl3, as well as other organic solvents. Polymers containing ratios of hydroquinone/BPA greater than 60/40 show a crystalline melting point by DSC at about 310°C and a glass transition temperature at 154°C.
Structurally perfect ladder polymers: Shape and conversion
Authors: Löffler M. , Schlüter A.‐D.
Published: March 2011

The influence of the symmetry and rigidity of Diels‐Alder (DA) ladder polymers on their shape in solution is discussed. Theoretical evidence is presented, which shows that certain representatives of this class of polymers attain the unprecedented shape of two‐dimensional coils. The second half of this article describes how one can unfold these polymers with chemical transformations and possibly even obtain fully aromatic ribbons.
Phase behavior of polymer blends under equilibrium and nonequilibrium conditions
Authors: Kammer Hans W.
Published: March 2011

This contribution embraces two topics related to phase behavior of polymer blends under equilibrium and nonequilibrium. 1. Polymer blends can undergo different phase changes as liquid‐liquid phase transition and crystallization. Coupling of demixing and crystallization may occur at the kinetic stage. This is illustrated by blends of poly(ϵ‐caprolactone)(PCL) and poly(styrene‐co‐acrylonitrile)(SAN). 2. Extension of studies to blend systems under flow is necessary for the better understanding of structure formation in polymer blends outside equilibrium. Polymer molecules will be oriented and stretched when subjected to flow. This may result in flow‐induced phenomena. Effects of flow on the phase behavior have been studied only for a few blends, as yet. The primary observation was flow‐induced miscibility. Apparent shifts of the phase transition temperatures will be discussed qualitatively in terms of a decoupled mode theory.
Phase separation studies on poly(vinylidene fluoride) and poly(methyl methacrylate) quenched blends
Authors: Martínez‐Salazar J. , Canalda J. C. , Vallejo B.
Published: March 2011

A combined study by SAXS and DSC on quenched blends of PVDF and PMMA is presented. Attention is focused on the first stage of the phase separation process during annealing that is shown to be mainly determined by the diffusion of the PVDF molecules from the amorphous blend phase towards the crystals growth front. The experimental monomer diffusion constants at T > Tg are compared with those expected theoretically using the approximation of the fast model process and the WLF equation for the relaxation frequency of the monomer. The nature and composition of the crystal interphase are discussed in terms of the SAXS invariant for the whole system and the calorimetric data derived from the Tg transitions observed.
Plastic deformation of polymer blends with crystallizable components
Authors: Galeski Andrzej
Published: March 2011

The application of polymer blends depends mostly on their high ability to plastic deformation. Usually the studies of plastic deformation behavior include only the stress‐deformation relationship and investigation of changes of morphology of the blends on the size level of inclusions. The energy absorption is also often considered. The presented, more rigorous, approach to plastic deformation of polymer blends containing a crystallizable component involves the studies of crystal plasticity and associated deformation of the amorphous phase. Plastic deformation of blends containing high‐density polyethylene and isotactic poly(propylene) with other components were studied in two modes of deformation: 1. that avoids internal cavitation and 2. in tension with intense voiding. When no internal cavitation was involved, the plastic deformation was crystallographic in nature while the amorphous phase deformed in a manner to accommodate for the rotation and slips of the crystalline phase. Also the plastic deformation associated with intense voiding leads to a preferred orientation of certain crystallographic planes containing macromolecular chains which strongly suggests that the leading mechanisms in plastic deformation of blends are of crystallographic nature. The plastic deformation behavior depends very much on the glass transition of the amorphous component of the blend.
Polymer dynamics in random media, replica theory, ternary polymer systems: Mappings and equivalences
Authors: Ebert Ute , Schäfer Lothar
Published: March 2011

For polymer dynamics in quenched random media a renormalizability proof is lacking and calculations are lengthy. We here propose and define the static and the ergodic limit of the dynamic theory, and show, that these limits are equivalent to well‐known renormalizable static polymer theories. This procedure supplies us with a renormalizable substructure and puts the 2 loop analysis of the full theory within reach.
The glass transition in polymer melts
Authors: Baschnagel Jörg , Lobe Bernhard
Published: March 2011

This paper presents some results of a Monte Carlo simulation for the glass transition in two‐ and three‐dimensional polymer melts. The melt was simulated by the bond‐fluctuation model on a d‐dimensional cubic lattice which was combined with a two‐level hamiltonian favouring long bonds in order to generate a competition between the energetic and topological constraints in the system. This competition prevents crystallization and makes the melt freeze in an amorphous structure as soon as the internal relaxation times match the observation time of the simulation set by the cooling rate. The freezing point of the melt, i.e the glass transition temperature Tg, thus depends upon the cooling rate and additionally upon the chain length of the polymers. The dependence of the glass transition temperature on the cooling rate was closely analysed in three and that on the chain length in both two and three dimensions, resulting in a non‐linear relationship between Tg and the logarithm of the cooling rate and a linear relationship between Tg and the inverse chain length, respectively. In addition to this behaviour of the melt during the cooling process an example for the relaxational properties of the three‐dimensional model is provided by a quantitative analysis of the incoherent intermediate scattering function in the framework of the idealized mode coupling theory.
Flow‐alignment and rheology of polymer melts: Computation of the single‐link orientational distribution function
Authors: Kröger Martin
Published: March 2011

The single‐link orientational distribution function and the space‐averaged stresses in the fluid are computed for the case of steady shear flow of polymer melts. The computation is achieved with Galerkin's method with spherical harmonics and Euler polynomials as trial functions. The stress components become power functions of shear rate when the latter is large. The single‐link orientational distribution function f solves the Fokker‐Planck equation subject to a boundary condition for f at the chain ends. A solution is obtained for every shear rate and ratio of the orientational and one‐dimensional diffusion coefficient. It is demonstrated that the Fokker‐Planck equation with appropriate boundary condition is useful in order to predict the flow‐alignment and stresses in good agreement with experimental data as well as with recent results of a nonequilibrium molecular dynamics computer simulation on polymer melts.
Structural properties and swelling behavior of randomly crosslinked polymer networks: A monte carlo study
Authors: Sommer Jens‐Uwe
Published: March 2011

The structural properties as well as some aspects of the swelling behavior of randomly crosslinked polymer networks obtained by lattice Monte Carlo simulations are investigated.

For a crosslink density of about 10 crosslink points per precursor chain, unusual structural properties are observable on scales well beyond the mesh size. For scales of order of the averaged mesh size an inner dimension of di ≅ 1.15 and for scales up to the lattice size di ⋍ 2.2 can be obtained. For the autocorrelation function of a random walker placed on the network topology, these properties can be reproduced.

In the case of athermal swelling of the network structure inhomogeneous deformation of the individual network chains can be observed. Additionally the average network chain deformation is considerably less than the macroscopic swelling ratio.

The swelling pressure of the network shows a scaling behavior different from the corresponding uncrosslinked system. This can be related to the fractal properties of the network within the correlation length by applying the well known scaling theory for the osmotic pressure for semidiluted polymers to fractal objects. This explains the swelling anomalies for polymer network even in the case of athermal swelling.
Polymer adsorption on heterogeneous surfaces
Authors: van Der Linden Catharina C. , Leermakers Frans A. M.
Published: March 2011

The adsorption of polymers on an energetically heterogeneous surface can be modelled using a self‐consistent field lattice theory. The surface consists of sites having different adsorption energies. It turns out that the distribution of the sites over the surface is one of the main parameters determining the adsorption behaviour.
New copolymers of vinylidene fluoride
Authors: Tournut Claude
Published: March 2011

After a brief presentation of the standard non‐functionalized copolymers of vinylidene fluoride, the preparation of new functionalized copolymers is described, by copolymerization of vinylidene fluoride, with other fluoromonomers and non‐fluorinated monomers including at least one hydroxy or other functional group. The copolymers are analysed by the conventional methods. Examples of formulation show that these new copolymers are able to give coatings applicable outdoors and offering the same excellent durability as PVDF.
Surface active fluorosilicone polymers
Authors: Owen Michael J. , Kobayashi Hideki
Published: March 2011

The introduction of low‐intermolecular‐force, aliphatic fluorocarbon groups into siloxane polymers has produced a variety of useful, low surface tension materials including Rf(CH2)2SiO3/2 self‐assembled polymer monolayers and silsesquioxane polymers, and [Rf(CH2)2MeSiO]n siloxanes. The surface tensions of such materials measured by the contact angle approaches of Owens‐Wendt and Girifalco‐Good‐Fowkes‐Young are reviewed and compared with the direct determination from work of adhesion studies based on the Johnson, Kendall and Roberts theory. The lowest surface tension fluorosilicones available are as oleophobic and hydrophobic as any known fluoropolymer. The most efficient, effective incorporation of fluorine in these fluorosilicones is generally achieved with the CF3(CF2)3(CH2)2 group, making these nonafluorohexyl‐containing species the most commercially attractive.
A biodegradable material for ACL reconstruction
Authors: Gisselfält Katrin , Flodin Per
Published: March 2011

Biodegradable polyurethane urea fibers for ACL reconstruction have been produced by wet spinning. By using a short‐chain polyester diol as the soft segment in the polyurethane urea the elongation‐to‐break of the fibers have been reduced to be below 100% instead of 400–800% for spandex fibers, the modulus is increased from 5 MPa to 1 GPa and the tensile strength is increased from 0.1 N/tex to 0.4 N/tex. The composition of the polyester determines at which rate the fiber degrade. Different polyesters have been investigated to find the most suitable degradation rate for ACL application.
Biological basis of enzyme‐catalyzed polyester degradation: 59 C‐terminal amino acids of poly(3‐hydroxybutyrate) (PHB) depolymerase a from pseudomonas lemoignei are sufficient for PHB binding
Authors: Briese Bernd Holger , Jendrossek Dieter
Published: March 2011

Biodegradable polyesters such as biologically produced poly[(R)‐3‐hydroxybutyric acid], (PHB) other polyhydroxyalkanoic acids and related chemosynthetic polyesters have attracted industrial interest, and bacterial produced PHB is commercially available since 1990. A large variety of polyester degrading microorganisms have been found to be present in environment. The microorganisms decompose the polymers by secretion of extracellular polyester depolymerases and utilize low molecular weight degradation products for growth. Microbial polyester depolymerases have the unique property to be water soluble and to be able to bind specifically to polyester surfaces. The objective of this contribution is a functional analysis of a bacterial PHB depolymerase polyester binding domain. In addition, a detailed summary of the present knowledge on the biochemistry of enzymatic polyester hydrolysis is provided.
Biodegradable liquid‐crystalline aromatic polyesters
Authors: Kricheldorf Hans R. , Wahlen Lars , Stukenbrook Thomas
Published: March 2011

Two strategies designed for the mechanical reinforcement of biodegradable polyesters, such as poly‐(ε‐caprolactone), poly (L‐lactide) and their copolyesters, are described. Both strategies utilize more or less biodegradable thermotropic aromatic polyesters as reinforcing component. However, the structures of the aromatic polyesters differ largely. For strategy I polyesters composed of substituted hydroquinones and substituted terephthalic acids are used (which may contain anhydride groups), whereas the polyesters of strategy II are made up of natural nontoxic monomers such as β‐(4‐hydroxyphenyl) propionic acid and 4‐hydroxybenzoic acid.
Local dynamics and glass transition
Authors: Erman Burak , Bahar Ivet
Published: March 2011

The dynamics of polymer chains in the bulk state are discussed at three different temperature scales: (i) Well above the glass transition temperature where the basic step of motion is the rotameric transition of bonds. In this regime, the dynamics may conveniently be analyzed by the rotational isomeric state model, (ii) In the vicinity of glass transition where friction forces from the environment dominate. In this regime, the dynamics may be modeled according to the cooperative kinematics model, (iii) Well below glass transition. Here, an analogy with a native protein is made, and the mean‐squared fluctuations are analyzed by adopting the Gaussian Network Model, which recently proved successful in describing fluctuations in native proteins.
Combined assimilation of screen‐level observations and radar‐derived precipitation for soil moisture analysis
Authors: Mahfouf Jean‐François , Bližňák Vojtěch
Published: March 2011

A methodology is proposed in order to combine information from radar precipitation with other observations (e.g. screen‐level temperature and relative humidity) in a soil analysis scheme based on an extended Kalman filter. A preliminary study is performed over the Czech Republic for one month in July 2008 using three‐hour rainfall accumulations derived from two C‐band radars and a land‐surface scheme forced by short‐range forecasts from a limited‐area model. The Jacobian matrix of the observation operator is examined to make optimal choices for the estimation of the Kalman gain matrix. It is shown that the size of the perturbation for computing Jacobian matrix elements with finite differences has to be carefully chosen, since too small values lead to unphysical negative elements whereas too large values reduce the spatial variability considerably. After a log‐transform of the precipitation field, the corresponding errors are more compatible with the Gaussian hypothesis of the Kalman filter. However, at locations where model rainfall is underestimated, positive soil moisture increments are much too low. Finally, two methods for combining the assimilation of screen‐level observations with radar precipitation are compared. A first evaluation shows more accurate soil analyses (leading to reduced screen‐level parameter forecast errors) when both sources of information are considered to correct soil moisture contents. Avenues for improving the specification of observation and model errors of the precipitation field are also discussed. Copyright © 2011 Royal Meteorological Society
Exohedral functionalization of fullerenes and supramolecular chemistry
Authors: Nakamura Yosuke , Kato Shin‐Ichiro
Published: March 2011

We have investigated the exohedral functionalization of [60]fullerene, especially bisaddition; we have revealed the regioselectivity of bisaddition and the properties of obtained bisadducts. The bisaddition without any restriction generally shows low regioselectivity. The electronic and photophysical properties of bisadducts mainly depend on the addition patterns and are almost independent of the nature of addends. We have also attained the regioselective synthesis of bisadducts by controlling the distance and orientation between two reactive species with suitable covalent templates and their application into some functional materials. The synthesis of fullerene‐containing interlocked molecules, such as catenanes and rotaxanes, was accomplished by using a noncovalent interaction, mainly a donor‐acceptor interaction, in addition to the covalent functionalization. The bistable rotaxanes, which can serve as a molecular shuttle or switch, were also successfully prepared. DOI 10.1002/tcr.201000036
Postgenomic technologies targeting the Wnt signaling network
Authors: Pancratov Raluca , DasGupta Ramanuj
Published: March 2011

The recent development of high‐throughput sequencing technologies and the availability of whole genome sequences of a variety of living organisms, including that of humans, have led to an enormous push in the quest for a comprehensive inquiry for the function of each and every gene discovered in different model organisms. A major conclusion from the sequencing projects was that while forward genetics had been extremely successful in identifying key genes/components of many biological processes, such as signal transduction cascades, the function(s) of the majority of genes in the genome remains a mystery. In this article, we discuss the use of a variety of high‐throughput postgenomic tools, including functional genomics, proteomics, and chemical genetics that are being implemented in an exhaustive molecular dissection of a key evolutionarily conserved signal transduction pathway, namely the Wnt/wingless (wg) pathway and its associated signaling network. WIREs Syst Biol Med 2011 3 649–665 DOI: 10.1002/wsbm.140

This article is categorized under:

Laboratory Methods and Technologies > Genetic/Genomic Methods
Consultation to halfway houses
Authors: Budson Richard D.
Published: March 2011

The consultant must assume the role of a wise friend who shares his clinical skills, judgment, experience, patience, and tolerance with all people involved in the complex system of the halfway house.
Evolution and Development of Surgery for Large Paraesophageal Hiatus Hernia
Authors: Watson David I.
Published: March 2011

Laparoscopic repair is the standard surgical approach to the problem of large paraesophageal hiatus hernia. It is associated with low risks of morbidity and mortality, although there is a small risk (less than 5%) of a clinically significant recurrent hernia. Various techniques have been proposed to minimise this risk, including esophageal lengthening procedures and mesh reinforcement of the hiatus. Both remain controversial. Radiological outcomes from randomised trials suggest that a reduction in hernia recurrence rates can be achieved with the use of mesh repair, although these trials have not demonstrated any clinically significant benefits for mesh repair. The risk of complications following mesh placement at the esophageal hiatus or an esophageal lengthening procedure needs to be balanced against potential benefits. More work is required to define the optimal approach to repair of large paraesophageal hiatus hernias.
Surface Microtextures of Quartz Grains from the Central Coast of Tamil Nadu
Authors: P. Udayaganesan , N. Angusamy , A. R. Gujar , G. V. Rajamanickam
Published: March 2011

Quartz grain surface micro textures of 12 samples collected from the beach were examined under scanning electron microscopy to understand the role of coastal processes on their transportation and deposition. The study area has been divided into three sectors on the basis of drainage, geomorphology and nature of the beach and shelf topography. Surface textures of the northern sector display an array of mechanical features like conchoidal fracture, V marks and impact pits, indicating the dominance of mechanical processes. However, silica precipitation in the form of globules indicates an added influence of chemical processes in the Northern sector. The presence of chemical features in northern sector, where energy level is high, corroborates the addition of quartz grains from paleo-sediments, from the nearby Tertiary and Cretaceous formations. Central sector quartz grains display the signatures of chemical and mechanical processes. The presence of step like furrows in southern sector is an indicator of fluvial low energy conditions, and supplements the role of littoral currents in depositing the quartz grains along the coastal region.
Grams, Calories, and Food: Languages of Victimization, Entitlement, and Human Rights in Occupied Germany, 1945–1949
Authors: Grossmann Atina
Published: March 2011

By spring 1945 when the Allied Military Government and the United Nations Relief and Rehabilitation Administration (UNRRA) confronted the masses of refugees and displaced persons gathered in, or streaming toward, occupied Germany in the wake of the Third Reich's defeat, food—its supply, distribution, and, not least, symbolic meaning—had been clearly established as a key political and psychological issue for military and occupation policy. The rhetoric of allied war aims and of relief work posited food provision as a fundamental issue of human survival, development, and dignity. In 1943, the anthropologist Margaret Mead, deploying both political and psychoanalytically oriented social work discourses, cautioned American policy makers planning the future of a defeated Nazi Germany about the importance of rationing for establishing control over an occupied population. “Whenever a people feels that its food supply is in the hands of an authority,” she reminded them—in terms suffused with unarticulated gender assumptions, “it tends to regard that authority as to some degree parental.” Moreover she added, “probably no other operation, even the provision of hospitalization and emergency care, is so effective in proving to an anxious and disturbed people that the powers that be are good and have their welfare at heart.”
Embrayages narratifs en philosophie cartésienne
Authors: Méthot Jean-François
Published: March 2011

Nous examinons la narrativité du discours cartésien pour entamer un exercice herméneutique qui met en évidence quelques aspects des récits cartésiens, et qui montre que loin d’être un procédé littéraire, ou un simple agrément, le récit cartésien joue un rôle d’embrayeur au plan de la conceptualisation et de l’argumentation. La narrativité cartésienne met en jeu une double mimêsis qui est rétrospective dans les textes métaphysiques, et prospective dans les textes scientifiques. Ces deux directions remplissent des fonctions épistémologiques différentes.
Matérialisme et unité de l’être humain : le défi du dualisme cartésien chez La Mettrie et d’Holbach
Authors: Dumouchel Daniel
Published: March 2011

Le présent article se propose de réfléchir sur le rôle que joue la pensée philosophique de Descartes chez deux des principaux philosophes matérialistes du xviiie siècle, Julien Offray de La Mettrie et le baron d’Holbach. Alors que les deux philosophes s’entendent sur le caractère aberrant et inintelligible de la spiritualité de l’âme, l’interprétation qu’ils font de la signification des conséquences du cartésianisme diffère. Tandis que l’auteur de L’homme-machine feint de voir dans le dualisme cartésien une ruse destinée aux théologiens, qui cache un matérialisme souterrain qui ne révélerait sa véritable portée que dans l’analogie de la machine appliquée à l’être humain, l’auteur du Système de la nature élève l’erreur cartésienne au rang d’emblème de l’ignorance philosophique causée par l’autonomisation de l’imagination théorique.
Preaching to Princes: John Burgess and George Hakewill in the Royal Pulpit
Authors: RHATIGAN EMMA
Published: March 2011

This article examines a previously unnoticed link between the Puritan John Burgess and the Calvinist conformist George Hakewill. In 1604 Burgess preached a court sermon so outspoken and critical of James i's religious policy that he was imprisoned. Nearly twenty years later, however, Hakewill chose to incorporate extended passages from Burgess's sermon into the series of sermons, King David's vow (1621), preached to Prince Charles's household. This article considers why Burgess's sermon became so resonant for Hakewill in the early 1620s and also demonstrates how Hakewill deliberately sought to moderate Burgess's strident polemic. In so doing the article provides important new evidence for the politically attuned sermon culture at Prince Charles's court in the early 1620s and also suggests how, as the parameters for clerical conformity shifted in the latter years of James's reign, Calvinist conformists found a new appeal in the works of moderate Puritans.
MADAME GUIZOT AND MONSIEUR GUIZOT: DOMESTIC PEDAGOGY AND THE POST-REVOLUTIONARY ORDER IN FRANCE, 1807–1830
Authors: BATES ROBIN
Published: March 2011

When the husband-and-wife team of François and Pauline Guizot looked at early nineteenth-century France, they saw an institutional wasteland where the Revolution had annihilated settled habits, mentalities, and structures. Beginning with collaborative work on pedagogy, they envisioned a new order adequate to the post-Revolutionary era. In their imaginative universe, moral suasion ultimately trumps direct physical coercion. Resistance and manipulation subvert the imperious imposition of an iron will, while an abiding spiritual form of power comes from renouncing forceful commands in favor of sentimental ascendancy. They advanced this as an all-embracing social truth applicable to many different domains from domesticity to government. Their wide-ranging theory of human relations blossomed into thegouvernement des esprits(“government of minds”) which intellectually underwrote François's Doctrinaire liberalism when he entered politics. Meanwhile, Pauline pursued her reflections on post-Revolutionary society in deceptively simple children's stories which instantiate their philosophy in concrete human relationships.
BEYOND “ACADEMICIZATION”: THE POSTWAR AMERICAN UNIVERSITY AND INTELLECTUAL HISTORY
Authors: TEICHGRAEBER RICHARD F.
Published: March 2011

The still astonishing expansion of the American university since World War II has transformed the nation's intellectual and cultural life in myriad ways. Most intellectual historians familiar with this period would agree, I suppose, that among the conspicuous changes is the sheer increase in the size and diversity of intellectual and cultural activity taking place on campuses across the country. After all, we know that colleges and universities that employ us also provide full- and part-time academic appointments to novelists, poets, playwrights, filmmakers, choreographers, composers, classical and jazz musicians, painters, photographers, and sculptors, even though most of them probably began their careers with little or no desire to join us in the halls of academe. This now widespread employment practice has decentralized the nation's literary and artistic talent. It also has made for a manifold increase in degree-granting programs in writing and the creative arts. One example will suffice here. When World War II ended, there were a small handful of university-based creative-writing programs. Over the course of the next thirty years, the number increased to fifty-two. By 1985, there were some 150 graduate degree programs offering an MA, MFA, or PhD. As of 2004, there were more than 350 creative-writing programs in the United States, all staffed by practicing writers and poets, many of whom now also hold advanced degrees in creative writing. (If one includes current undergraduate degree programs, the number grows to 720.)
Comparative Epidemiology of Suicide in South Korea and Japan: Effects of Age, Gender and Suicide Methods
Authors: Kim Seong Yi , Kim Myoung-Hee , Kawachi Ichiro , Cho Youngtae
Published: March 2011

Background: Suicide is one of the leading causes of mortality in both South Korea and Japan. Aims: The study aims to compare the descriptive epidemiology of suicide over the last two decades (1985–2006) and to explore the conditions associated with the different distribution of suicides in both countries. Methods: Age-standardized suicide rates were obtained from the OECD Health Data 2009. Age-specific suicide rates for the age groups were calculated from the WHO Mortality Database. Suicide methods were identified based on ICD-10. Results: Through 1980–2000, Japan showed consistently higher suicide rates compared to Korea. However, from the mid-1990s, Korea showed an acute increase of suicides and finally surpassed Japan; the age-standardized suicide rate of Korea increased from 10.2 (per 100,000) in 1985 to 21.5 in 2006, while it slightly increased from 18.4 to 19.1 in Japan. The highest age-specific suicide rate was observed among Japanese men aged 45–64 years and Korean men aged over 64 years. The increase of elderly suicides among Korean women was notable. The gender ratio increased in Japan and decreased in Korea, respectively. The preferred suicide methods were hanging and pesticide poisoning in Korea and hanging in Japan. Because of the limited number of observations, hypothesis testing of specific risk factors was not possible. Conclusions: Age and gender distribution of suicide rates differed considerably between the two countries. Welfare protection throughout the life course in both countries, and pesticide regulation in Korea would be helpful in reducing the burden of suicide mortality in both countries, even if the social values could not be changed in a short time.
Thermal boundary resistance of copper phthalocyanine-metal interface
Authors: Jin Y. , Yadav A. , Sun K. , Sun H. , Pipe K. P. , Shtein M.
Published: March 2011

Systems containing interfaces between dissimilar materials can exhibit lower thermal conductivity than their pure constituents, with important implications for thermal management and thermoelectric energy conversion. However, the heat transfer processes at such interfaces, in particular those between organic and inorganic materials, remain for the most part uncharacterized. We use vacuum thermal evaporation to grow archetypal multilayer thin films of copper phthalocyanine (CuPc) and Ag or Al, and measure their thermal conductivity as a function of interface density. We observe large thermal boundary resistance values (7.8×10−8 m2 K/W for CuPc/Ag and 2.0×10−8 m2 K/W for CuPc/Al), attributable to acoustic mismatch, heat carrier mismatch, and weak bonding.
On the constrained B-type Kadomtsev–Petviashvili hierarchy: Hirota bilinear equations and Virasoro symmetry
Authors: Shen Hsin-Fu , Tu Ming-Hsien
Published: March 2011

We derive the bilinear equations of the constrained BKP hierarchy from the calculus of pseudodifferential operators. The full hierarchy equations can be expressed in Hirota's bilinear form characterized by the functions ρ, σ, and τ. Besides, we also give a modification of the original Orlov–Schulman additional symmetry to preserve the constrained form of the Lax operator for this hierarchy. The vector fields associated with the modified additional symmetry turn out to satisfy a truncated centerless Virasoro algebra.
Inversion of two-dimensional potentials from frequency-resolved spectroscopic data
Authors: Li Xuan , Shapiro Moshe
Published: March 2011

We report the first successful reconstruction of two-dimensional potential energy surfaces (PES) using the magnitudes and positions of a set of frequency-resolved fluorescence (or absorption) lines. The inversion proceeds by first extracting the phases of the transition-dipole matrix elements, yielding, together with the (ground) PES to (from) which emission (absorption) occurs, a point by point reconstruction of the two-dimensional excited state PES. The inversion procedure is highly accurate even for PES with multiple minima and many missing lines, with typical RMS errors <0.002 cm−1 in the classically allowed region and <0.018 cm−1 in the classically forbidden region.
Fully-inverted piezoresponse hysteresis loops mediated by charge injection in 0.29Pb(In1/2Nb1/2)O3–0.44Pb(Mg1/3Nb2/3)O3–0.27PbTiO3 single crystals
Authors: Li Qian , Liu Yun , Schiemer Jason , Smith Paul , Li Zhenrong , Withers Ray L. , Xu Zhuo
Published: March 2011

The domain structure and local switching behavior of ternary relaxor (001) 0.29Pb(In1/2Nb1/2)O3–0.44Pb(Mg1/3Nb2/3)O3–0.27PbTiO3 single crystals are studied using piezoresponse force microscopy. The as-grown crystals exhibit a labyrinthine domain pattern similar to other relaxor-based ferroelectrics. Abnormally switched domains are observed for both positive and negative tip-voltages, with sign-dependent thresholds and growth rates on the poled crystals. Further piezoresponse hysteresis loop measurements show that fully inverted loops can be observed under high switching voltages, mediated by injected charge fields. The dynamic behavior of the observed abnormal switching is qualitatively analyzed and the underlying mechanisms discussed.
Binding mechanisms of molecular oxygen and moisture to graphene
Authors: Yang Yinxiao , Murali Raghu
Published: March 2011

We report on the binding mechanisms of oxygen and water to graphene by comparing the doping of graphene in a dry O2 environment versus in ambient. It is seen that dry oxygen dopes graphene from the basal plane while the ambient dopes graphene from the edges or from the substrate in the vicinity of the edge. Upon vacuum annealing, doping is fully reversible in the former case and only partially reversible in the latter case. We observe a thickness-dependent doping as a result of the difference in host sites for doping (basal plane versus edge). Finally, hysteresis is shown to be triggered even in dry oxygen.
Homogeneous-materials-constructed electromagnetic field concentrators with adjustable concentrating ratio
Authors: Li Wei , Guan Jianguo , Wang Wei
Published: March 2011

Based on a two-step linear optical transformation method, a homogeneous-materials-constructed electromagnetic field concentrator whose energy concentrating ratio varies with the incident angle of the electromagnetic wave is proposed. The design is achieved by compressing the space in different directions with different ratios. Numerical simulations are performed to demonstrate the properties, especially the wave-incident angle-dependent concentrating effect of the concentrator. The relationship between the wave-incident angle and the concentrating ratio is investigated and the corresponding analytical expression is given and verified. This wave-incident angle-dependent concentrator constructed with homogeneous materials shows an advantage of facilitating the implementation in practice and provides a convenient route to continuously adjust the concentrated energy density in a pre-defined strategy.
Acoustic planar hyperlens via transformation acoustics
Authors: Wu Liang-Yu , Chen Lien-Wen
Published: March 2011

An acoustic planar hyperlens is designed using transformation acoustics. Magnification effects are added to a planar channelling lens to obtain the planar hyperlens. A layered system approach is employed to achieve an effective transformation medium. The proposed planar hyperlens is capable of magnifying sub-diffraction-limit objects on one flat surface and forming magnified images which are above the diffraction limit on another flat surface.
Lighting the route to success
Authors: Shetach Ana
Published: March 2011

Purpose

This paper aims to provide team‐leaders and project managers with a practical and easily‐applicable managerial tool for coping with the large number of obstacles that may stand in the way to obtaining effective, efficient and altogether successful results, in overall management processes of projects and decisions within teams.

Design/methodology/approach

Relying on two previously published managerial tools, the “revised decision square model” and the “capi” model, this paper proceeds to present an integrated model, the team managerial coping flowchart, for the successful handling of team assignments and projects, towards the management of effective and efficient team decision making and implementation processes over time.

Findings

The paper relies on testimonies of managers who have adopted the proposed strategy for their every‐day use.

Practical implications

The model offers a practical step‐by‐step set of guidelines, to lead managers towards a relatively high level of control in the management of effective and efficient team decision making and implementation processes, ensuring their route toward successful achievements.

Originality/value

Limited attention has been given in the literature to the studying of practical and applicable managerial techniques to successful decision‐implementation in teams. The paper focuses on this neglected domain, proposing a solution in the form of an integrative strategy.
Virtual team collaboration and innovation in organizations
Authors: Jarle Gressgård Leif
Published: March 2011

Purpose

Virtual teams, understood as teams with geographically dispersed members communicating primarily by use of information and communication technologies (ICT), have become a viable form for work in innovation projects involving one or several organizations. Knowledge development and creation of a shared understanding among team members are often stressed as fundamental to successful innovation processes. This paper aims to address how use of ICT in team collaboration impacts on the creation of a shared understanding and knowledge development within the teams, and how these factors are important for organizations' innovation capabilities.

Design/methodology/approach

Based on a review of the literature, the paper discusses how modern ICT may impact on the organization of innovative activities and organizations' innovation capabilities.

Findings

Several important factors related to the use of ICT in teams working on innovation projects are highlighted. A conceptual model and directions for future research based on a literature review are proposed.

Practical implications

Based on the discussion, a conceptual model is presented which highlights the need for well‐functioning computer‐mediated team interaction in order to realize the innovation potential of organizations.

Originality/value

The paper emphasizes the reciprocal significance of knowledge access and knowledge exploitation for organizations' innovation capabilities, and discusses how ICT impacts on both aspects.