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Perfection
Kinds of Perfection Selected AbstractsWHEN PERFECTION IS THE ENEMY OF THE GOODECONOMIC AFFAIRS, Issue 4 2002Julian Morris No abstract is available for this article. [source] EXILE FROM PERFECTION IN IRIS MURDOCH'S PHILOSOPHICAL TEXTSTHE HEYTHROP JOURNAL, Issue 1 2010TONY MILLIGAN Iris Murdoch's philosophical texts set out the egocentric dangers of guilt but still endorse an account of original sin. This might seem like an unstable combination as these two are in tension, but I argue that Murdoch manages to use this tension in a productive manner. The human condition is treated as one of fallenness, in the sense of an exile from perfection. We are aware of moral failure and also aware of the standard by which we fail. Guilt is reined in, however, by the fact that such failure is a matter of commonplace flawed moral vision and not an Augustinian perversity of the will. This reining in of guilt is still accompanied by a recognition of our unbridgeable remoteness from perfection. [source] Initial feasibility of a multi-station high resolution three-dimensional dark blood angiography protocol for the assessment of peripheral arterial diseaseJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2009Georgeta Mihai PhD Abstract Purpose To evaluate the feasibility of a multi-station three dimensional (3D) T1-weighted turbo spin echo (TSE) dark-blood Sampling Perfection with Application optimized Contrasts using different flip angle Evolution sequence (T1w-SPACE), to assess aorta, iliac, and superficial femoral (SFA) arteries (inflow vessels) by comparing it with a multi-station contrast enhanced MR angiography (CE-MRA) with identical resolution. Materials and Methods A total of 6 volunteers and 14 peripheral arterial disease (PAD) patients were included in the study. Abdominal and thigh T1w-SPACE and lower leg time-resolved MRA (TR-MRA) with low dose contrast were followed by 3-station CE-MRA. Quantitative measurements of lumen area at 17 locations from T1w-SPACE and CE-MRA were obtained. Additionally, vessel wall areas at the same locations were obtained from the T1w-SPACE images. Results Quantitative comparison of lumen areas with T1w-SPACE and CE-MRA revealed strong correlation between the two techniques and strong inter-observer agreement for each of the two imaging methods (r > 0.9; P < 0.001). Localized vessel wall area measurements obtained in PAD patients were significantly greater compared with those obtained in normal volunteers (mean difference 43.75 ± 12.46 mm2; P < 0.001). Stenosis severity obtained from T1w-SPACE localized measurements showed significant arterial area stenosis in PAD patients. Conclusion T1w-SPACE imaging of inflow vessels is feasible, and in addition to CE-MRA has the ability to assess atherosclerotic plaque and vascular remodeling. J. Magn. Reson. Imaging 2009;30:785,793. © 2009 Wiley-Liss, Inc. [source] Indigeneity across borders: Hemispheric migrations and cosmopolitan encountersAMERICAN ETHNOLOGIST, Issue 1 2010ROBIN MARIA DELUGAN ABSTRACT The increasing migration of indigenous people from Latin America to the United States signals a new horizon for the study of indigeneity,complexly understood as subjectivities, knowledge, and practices of the earliest human inhabitants of a particular place and including legal and racial identities that refer to these people. Focusing on indigenous migration to San Francisco, California, I explore how government, service providers, and community organizations respond to the arrival of new ethnic groups while also contributing to an expanding Urban Indian collective identity. In addition to reviewing such governmental practices as the creation of new census categories and related responses to indigenous ethnic diversity, I illustrate how some members of a diverse Urban Indian population unite through participation in rituals such as the Maya Waqxaqi' B'atz' (Day of Human Perfection), transplanted to San Francisco from Guatemala. The rituals recall homelands near and far in a broader social imagination about being and belonging in the world. The social imagination, borne in part through migration and diaspora, acknowledges the local and the particular in a framework of shared values about what it means to be human. I analyze this meaning making as cosmopolitanism in practice. By merging indigeneity and cosmopolitanism, I join other scholars who strive to decenter classical notions of cosmopolitan "worldliness," drawing attention to alternative sources of beneficent sociality and for cultivating humanity. [source] ChemInform Abstract: Toward Perfection: Kapellasite, Cu3Zn(OH)6Cl2, a New Model S = 1/2 Kagome Antiferromagnet.CHEMINFORM, Issue 7 2009R. H. Colman Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Infrared Microscopic Imaging of Bone: Spatial Distribution of CO32,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2001H. Ou-Yang Abstract This article describes a novel technology for quantitative determination of the spatial distribution of CO32, substitution in bone mineral using infrared (IR) imaging at ,6 ,m spatial resolution. This novel technology consists of an IR array detector of 64 × 64 elements mapped to a 400 ,m × 400 ,m spot at the focal plane of an IR microscope. During each scan, a complete IR spectrum is acquired from each element in the array. The variation of any IR parameter across the array may be mapped. In the current study, a linear relationship was observed between the band area or the peak height ratio of the CO32, v3 contour at 1415 cm,1 to the PO43, v1,v3 contour in a series of synthetic carbonated apatites. The correlation coefficient between the spectroscopically and analytically determined ratios (R2 = 0.989) attests to the practical utility of this IR area ratio for determination of bone CO32, levels. The relationship forms the basis for the determination of CO32, in tissue sections using IR imaging. In four images of trabecular bone the average CO32, levels were 5.95 wt% (2298 data points), 6.67% (2040 data points), 6.66% (1176 data points), and 6.73% (2256 data points) with an overall average of 6.38 ± 0.14% (7770 data points). The highest levels of CO32, were found at the edge of the trabeculae and immediately adjacent to the Haversian canal. Examination of parameters derived from the phosphate v1,v3 contour of the synthetic apatites revealed that the crystallinity/perfection of the hydroxyapatite (HA) crystals was diminished as CO32, levels increased. The methodology described will permit evaluation of the spatial distribution of CO32, levels in diseased and normal mineralized tissues. [source] Monocrystalline Cd0.2Zn0.8Te solid solution obtained by self-selecting vapour growthCRYSTAL RESEARCH AND TECHNOLOGY, Issue 9 2010A. Szczerbakow Abstract Cd0.2Zn0.8Te monocrystals with the sizes of about 15 mm have been produced by self-selecting vapour growth (SSVG). High degree of structural perfection of monocrystalline Cd0.2Zn0.8Te was achieved. Excellent compositional uniformity was observed as well. To our knowledge, no comparable results are reported for this solid solution. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Characterization of pure and doped potassium hydrogen tartrate single crystals grown in silica gelCRYSTAL RESEARCH AND TECHNOLOGY, Issue 5 2009I. Quasim Abstract Growth of pure-, sodium- and lithium- doped potassium hydrogen tartrate single crystals by gel technique is reported. Growth conditions conducive for the growth of single crystals are worked out. The crystals are characterized by using powder XRD, SEM, FTIR, AES, EDAX, CH analysis and thermoanalytical techniques. The stoichiometric composition for the grown crystals are established as KHC4H4O6.H2O, (K)0.98(Na)0.02.H2O and (K)0.94(Li)0.06HC4H4O6.H2O. Doping of sodium and lithium in the pure potassium hydrogen tartrate single crystals is found to influence the size, perfection, morphology, crystal structure and the thermal stability of crystals. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Structural and microhardness studies of pure and thiourea doped glycine phosphite single crystalCRYSTAL RESEARCH AND TECHNOLOGY, Issue 7 2008R. Ezhil Vizhi Abstract Ferroelectric Glycine Phosphite (GPI) crystal have been grown from aqueous solution employing the slow cooling technique. As the crystal solubility in water depends on temperature, single crystals were grown. Transparent, colourless crystals with habit morphology weighing about 8g were obtained with in a month. The same procedure was used to grow single crystals of 10 wt% of Thiourea doped GPI (TUGPI). Formation of a new crystal was confirmed by Powder X-ray diffraction studies as well as FTIR studies. Crystalline quality were found using rocking curve for both the crystals. Due to the presence of Thiourea in TUGPI, it improves the crystalline perfection and also enhances the growth rate. The variation of hardness on (010) faces of monoclinic GPI and TUGPI crystals, with load were studied.Vickers hardness numbers, Hv were found to decrease with the increase in load. The value of Mayer's index, ,n ' was found to be greater than 1.6 for GPI and TUGPI showing soft-material category. The results are discussed in detail. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Equilibrium and growth shapes of crystals: how do they differ and why should we care?CRYSTAL RESEARCH AND TECHNOLOGY, Issue 4-5 2005Robert F. SekerkaArticle first published online: 15 MAR 200 Abstract Since the death of Prof. Dr. Jan Czochralski nearly 50 years ago, crystals grown by the Czochralski method have increased remarkably in size and perfection, resulting today in the industrial production of silicon crystals about 30 cm in diameter and two meters in length. The Czochralski method is of great technological and economic importance for semiconductors and optical crystals. Over this same time period, there have been equally dramatic improvements in our theoretical understanding of crystal growth morphology. Today we can compute complex crystal growth shapes from robust models that reproduce most of the features and phenomena observed experimentally. We should care about this because it is likely to result in the development of powerful and economical design tools to enable future progress. Crystal growth morphology results from an interplay of crystallographic anisotropy and growth kinetics by means of interfacial processes and long-range transport. The equilibrium shape of a crystal results from minimizing its anisotropic surface free energy under the constraint of constant volume; it is given by the classical Wulff construction but can also be represented by an analytical formula based on the ,-vector formalism of Hoffman and Cahn. We now have analytic criteria for missing orientations (sharp corners or edges) on the equilibrium shape, both in two (classical) and three (new) dimensions. Crystals that grow under the control of interfacial kinetic processes tend asymptotically toward a "kinetic Wulff shape", the analogue of the Wulff shape, except it is based on the anisotropic interfacial kinetic coefficient. If it were not for long range transport, crystals would presumably nucleate with their equilibrium shape and then evolve toward their "kinetic Wulff shape". Allowing for long range transport leads to morphological instabilities on the scale of the geometric mean of a transport length (typically a diffusivity divided by the growth speed) and a capillary length (of the order of atomic dimensions). Resulting crystal growth shapes can be cellular or dendritic, but can also exhibit corners and facets related to the underlying crystallographic anisotropy. Within the last decade, powerful phase field models, based on a diffuse interface, have been used to treat simultaneously all of the above phenomena. Computed morphologies can exhibit cells, dendrites and facets, and the geometry of isotherms and isoconcentrates can also be determined. Results of such computations are illustrated in both two and three dimensions. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Vaccines, Viagra, and Vioxx: medicines, markets, and money,when life-saving meets life-style,DRUG DEVELOPMENT RESEARCH, Issue 2 2005David J. Triggle Abstract In this Commentary, life-style drugs will be termed as "those drugs for which there is a definable and real, but limited, therapeutic need, but a need that has been significantly stimulated by the cycle of pharmaceutical company advertising and pressure and public demand." The key to the continuing expansion of the life-style drug market is a progressive narrowing of the definition of "normal" coupled with campaigns launched by the pharmaceutical industry that persuade both patients and clinicians that a major and treatable disease does exist and that drug treatment, rather than acceptance of hair loss or occasional lack of sexual interest, and so on, is both necessary and appropriate. The expansion of the market for prescription drugs in this manner is now an integral part of the business model of the pharmaceutical industry. For society, the expanding role of these drugs, particularly those directed at "desires rather than diseases," raises ethical issues of our increasing obsession with a medically directed quest for perfection, and financial issues of the cost of this quest on the health care system and its priorities. For the pharmaceutical industry, there are questions of whether its role is life-saving or life-styling for a Huxleyan "Brave New World." Drug Dev Res 64:90,98, 2005. © 2005 Wiley-Liss, Inc. [source] Temperance, alcohol, and the American evangelical: a reassessmentADDICTION, Issue 7 2009Jessica Warner ABSTRACT Abstinence from alcohol is a way of life for many American evangelicals, with rates of abstention running at over 70% among some Pentecostal denominations. This paper examines the religious beliefs that, historically, have supported teetotalism. The most notable of these is Christian perfection, a doctrine that originated in 18th-century England, that was then radicalized in America in the early 19th century. Abstinence from alcohol is highest among denominations that make Christian perfection the cornerstone of their teachings, and lowest among those that discount human agency. The paper also argues that 19th-century American evangelicals were by no means committed uniformly to temperance as a way of life, and that this was especially true of the various Methodist churches. [source] Effects of Male Vocal Learning on Female Behavior in the Budgerigar, Melopsittacus undulatusETHOLOGY, Issue 10 2005Arla G. Hile Parrots are unusual among birds and animals in general in the extent of their ability to learn new vocalizations throughout life and irrespective of season. The budgerigar (Melopsittacus undulatus), a small parrot that is well suited for laboratory studies, has been the subject of numerous studies investigating the neurobiology of vocal learning. To date, few studies have focused on the function of vocal imitation by parrots. Previous work from our research group has shown that vocal imitation in budgerigars is sex-biased, as males paired with females learn vocalizations from their new mates, but not vice versa. This bias led us to hypothesize that vocal learning has a reproductive function. To test this hypothesis, we conducted two experiments. In the first experiment, we tutored males so that they could produce a call similar to one shared by a group of experimental females. The experimental females were then presented with one of the tutored males and another, equally unfamiliar, male that had not been tutored. We found that the females spent a greater proportion of time in proximity of, and made more affiliative displays toward, the tutored males. In the second experiment, seven males received small bilateral brain lesions that disrupt vocal learning. These males and an equal number of control males were then released into an aviary containing females and reproductive resources. We found that lesioned and control males were equally successful in obtaining social mates, but females mated to lesioned males were more likely to engage in extra-pair activities. These experiments indicate that a male's ability to imitate a female's call can influence the sexual behavior of the female even though lack of imitation ability does not appear to influence social pairing. We hypothesize that mate choice in budgerigars has multiple stages. Upon meeting a strange male, a female quickly assesses its ability for social acquisition of calls by the presence or absence of a call type similar to its own in its repertoire. As courtship proceeds into pair formation, the female assesses the ability of male to learn more directly by the extent of the male's perfection of imitation. [source] Polyamines and hair: a couple in search of perfectionEXPERIMENTAL DERMATOLOGY, Issue 9 2010Yuval Ramot Please cite this paper as: Polyamines and hair: a couple in search of perfection. Experimental Dermatology 2010; 19: 784,790. Abstract:, Polyamines (spermidine, putrescine and spermine) are multifunctional cationic amines that are indispensable for cellular proliferation; of key significance in the growth of rapidly regenerating tissues and tumors. Given that the hair follicle (HF) is one of the most highly proliferative organs in mammalian biology, it is not surprising that polyamines are crucial to HF growth. Indeed, growing (anagen) HFs show the highest activity of ornithine decarboxylase (ODC), the rate-limiting enzyme of polyamine biosynthesis, while inhibition of ODC, using eflornithine, results in a decreased rate of excessive facial hair growth in vivo and inhibits human scalp hair growth in organ culture. In sheep, manipulation of dietary intake of polyamines also results in altered wool growth. Polyamine-containing nutraceuticals have therefore been proposed as promoters of human hair growth. Recent progress in polyamine research, coupled with renewed interest in the role of polyamines in skin biology, encourages one to revisit their potential roles in HF biology and highlights the need for a systematic evaluation of their mechanisms of action and clinical applications in the treatment of hair disorders. The present viewpoint essay outlines the key frontiers in polyamine-related hair research and defines the major open questions. Moreover, it argues that a renaissance in polyamine research in hair biology, well beyond the inhibition of ODC activity in hirsutism therapy, is important for the development of novel therapeutic strategies for the manipulation of human hair growth. Such targets could include the manipulation of polyamine biosynthesis and the topical administration of selected polyamines, such as spermidine. [source] Czochralski-grown Single Crystals with Acentric Symmetry Group 32,ADVANCED ENGINEERING MATERIALS, Issue 7 2004R.B. Heimann Single crystals with calcium gallium germanate (Ca3Ga2Ge4O14, CGG) structure such as langasite La3Ga5SiO14 (LGS), its niobium (,langanite', La3Ga5.5Nb0.5O14, LGN) and tantalum (,langataite', La3Ga5.5Ta0.5O14, LGT) analogs as well as strontium niobium gallium silicate (Sr3NbGa3Si2O14, SNGS) and strontium tantalum gallium silicate (Sr3TaGa3Si2O14, STGS) were grown with high perfection by the Czochralski pulling technique. Specific electric conductivity, optical activity, and dielectric, piezoelectric, bulk and surface acoustic, elastic, and electro-optic properties were measured. [source] Protein tandem repeats , the more perfect, the less structuredFEBS JOURNAL, Issue 12 2010Julien Jorda We analysed the structural properties of protein regions containing arrays of perfect and nearly perfect tandem repeats. Naturally occurring proteins with perfect repeats are practically absent among the proteins with known 3D structures. The great majority of such regions in the Protein Data Bank are found in the proteins designed de novo. The abundance of natural structured proteins with tandem repeats is inversely correlated with the repeat perfection: the chance of finding natural structured proteins in the Protein Data Bank increases with a decrease in the level of repeat perfection. Prediction of intrinsic disorder within the tandem repeats in the SwissProt proteins supports the conclusion that the level of repeat perfection correlates with their tendency to be unstructured. This correlation is valid across the various species and subcellular localizations, although the level of disordered tandem repeats varies significantly between these datasets. On average, in prokaryotes, tandem repeats of cytoplasmic proteins were predicted to be the most structured, whereas in eukaryotes, the most structured portion of the repeats was found in the membrane proteins. Our study supports the hypothesis that, in general, the repeat perfection is a sign of recent evolutionary events rather than of exceptional structural and (or) functional importance of the repeat residues. [source] Perpendicularly Aligned, Size-and Spacing-Controlled Nanocylinders by Molecular-Weight Adjustment of a Homopolymer Blended in an Asymmetric Triblock CopolymerADVANCED FUNCTIONAL MATERIALS, Issue 15 2006U. Ahn Abstract Perpendicularly arrayed and size-controlled nanocylinders have been prepared by simply blending an asymmetric polystyrene- block -polyisoprene- block -polystyrene triblock copolymer with polystyrene (the minority component) homopolymers of different molecular weights. The preference for perpendicular orientation or hexagonal ordering of the nanocylinders over a large area in the asymmetric block copolymer can be controlled by adjusting the molecular weight of the blended homopolymer, and the perfection of hexagonal ordering of the perpendicular cylinders can be tuned by using a substrate whose surface tension is much different from that of the majority component of the block copolymer. Such highly controlled nanostructured block-copolymer materials, which have been obtained by a simple method independent of film thickness and interfacial tension between the blocks and the substrates, have wide-ranging commercial potential, e.g., for use in membranes and nanotemplates with size-tunable pores, bandgap-controlled photonic crystals, and other nanotechnological fields demanding a specific nanosize and nanomorphology. [source] On the Synthesis and Selective Deprotection of Low-Generation Dendrons with Orthogonally Protected Peripheral Amine Groups and a Possible Impact of the Deprotection Conditions on the Stability of Dendronized Polymers' SkeletonsHELVETICA CHIMICA ACTA, Issue 11 2006Rabie Al-Hellani Abstract The synthesis of first- and second-generation dendrons with defined ratios of orthogonally protected amine groups in the periphery ((benzyloxy)carbonyl (Cbz) and (tert -butoxy)carbonyl (Boc) protection) and the degree to which they can be selectively removed are described. The reaction conditions required for these deprotections were applied to methacrylic acid (=,2-methylprop-2-enoic acid) based dendronized polymers carrying the same peripheral protecting groups to investigate whether they have any detrimental interference with the polymer skeleton. Specifically it was explored whether dendrons attached to the backbone could possibly be cleaved off as a whole (de-dendronization). Finally it was investigated how de-dendronizations can be used for quantifying both the dendron-structure perfection and the polymer-backbone configurations. [source] John Colet, preaching and reform at St. Paul's cathedral, 1505,19,HISTORICAL RESEARCH, Issue 194 2003Jonathan Arnold As a Christian humanist, Colet attempted clerical reform partly by means of preaching. Evidence from Colet's ecclesiastical life as dean of St. Paul's suggests that his success was limited by the inappropriate expression of his idealistic ecclesiology, which demanded perfection. Although Colet's passion for preaching was shared and admired by humanist colleagues, his sermons received negative reactions from his cathedral clergy, the bishop of London and Henry VIII. The intellectual basis for Colet's ecclesiology was a combination of Pauline theology and Dionysian spirituality, which created a vision of Church perfection by means of purification and illumination. However, Colet sought a spiritual and moral revival, not a fundamental change to the structure of the Catholic Church. Colet's humanist success was achieved mainly outside the ecclesiastical world. [source] DO WEALTH DIFFERENCES AFFECT FAIRNESS CONSIDERATIONS?,INTERNATIONAL ECONOMIC REVIEW, Issue 2 2006Olivier Armantier The influence of relative wealth on fairness considerations is analyzed in an ultimatum game experiment in which participants receive large and widely unequal initial endowments. Subjects initially demonstrate a concern for fairness. With time however, behavior becomes at odds with both subgame perfection and fairness. Evidence of learning is detected for both proposers and receivers in the estimation of a structural reinforcement learning model. The estimation results suggest that, guided by foregone best responses and an acquired sense of deservingness, rich subjects become more selfish, whereas poor subjects, influenced only by their own experience, learn to tolerate this behavior. [source] An examination of exergy destruction in organic Rankine cyclesINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 10 2008P. J. Mago Abstract The exergy topological method is used to present a quantitative estimation of the exergy destroyed in an organic Rankine cycle (ORC) operating on R113. A detailed roadmap of exergy flow is presented using an exergy wheel, and this visual representation clearly depicts the exergy accounting associated with each thermodynamic process. The analysis indicates that the evaporator accounts for maximum exergy destroyed in the ORC and the process responsible for this is the heat transfer across a finite temperature difference. In addition, the results confirm the thermodynamic superiority of the regenerative ORC over the basic ORC since regenerative heating helps offset a significant amount of exergy destroyed in the evaporator, thereby resulting in a thermodynamically more efficient process. Parameters such as thermodynamic influence coefficient and degree of thermodynamic perfection are identified as useful design metrics to assist exergy-based design of devices. This paper also examines the impact of operating parameters such as evaporator pressure and inlet temperature of the hot gases entering the evaporator on ORC performance. It is shown that exergy destruction decreases with increasing evaporator pressure and decreasing turbine inlet temperatures. Finally, the analysis reveals the potential of the exergy topological methodology as a robust technique to identify the magnitude of irreversibilities associated with real thermodynamic processes in practical thermal systems. Copyright © 2008 John Wiley & Sons, Ltd. [source] Precise Control over Molecular Dimensions of Block-Copolymer Domains Using the Interfacial Energy of Chemically Nanopatterned Substrates,ADVANCED MATERIALS, Issue 15 2004W. Edwards Epitaxial assembly of block-copolymer films (see Figure) onto chemically nanopatterned substrates results in arrays of nanoscopic domains that are defect-free, oriented, and registered with the underlying substrate. The range of dimensions of features (or periodicity of structures) that can be patterned with perfection and registration strongly depends on the interfacial energy between the substrate and the polymer film. [source] Power and Wisdom: Toward a History of Social BehaviorJOURNAL FOR THE THEORY OF SOCIAL BEHAVIOUR, Issue 4 2003Akop P. Nazaretyan Cross-disciplinary studies carried out lately by Russian scholars discovered a causal relationship between the three variables: technological potential, cultural regulation quality, and social sustainability. The patterns called techno-humanitarian balance law, states that the higher production and war technologies' power, the more refined the behaviorregulation means (consolidated values and norms, etc.) that are required for self-preservation of the society. The article shows that the law has controlled social selection for all of human history and prehistory, discarding unbalanced social organisms, as far as they could not cope with ecological and (or) geopolitical crises, which had been caused by their own activities. It also shows how successive growth of instrumental opportunities in long-term retrospection has dramatically led to the consecutive perfection of cultural and psychological regulation mechanisms. Relevant calculations, comparative-anthropological evidence, and historical illustrations are provided. Regularities in mental processes are described that precede and accompany crisis-causing behavior, to certain extent regardless of population's historical and cultural peculiarities. [source] Toughening of basalt fiber-reinforced composites with a cyclic butylene terephthalate matrix by a nonisothermal production methodADVANCES IN POLYMER TECHNOLOGY, Issue 2 2010J. Baets Abstract The interest in thermoplastic composites is growing because of their advantages over thermosets, as well as their recyclability and higher toughness. The melt viscosity of thermoplastic polymers is very high, which makes fiber impregnation difficult. This difficulty can be overcome by the in situ polymerization with cyclic butylene terephthalate (CBT). However, this leads to a brittle polybutyleneterephthalate when isothermal RTM-production is applied. To solve this problem, a nonisothermal production process for composites with CBT as matrix material was developed and the influence on the toughness was investigated. In the nonisothermal production process, different cooling rates were applied to examine their influence on the toughness of the produced composites. The difference in composites properties was related to the difference in the degree of crystal perfection, which was investigated by differential scanning calorimetry. © 2010 Wiley Periodicals, Inc. Adv Polym Techn 29:70,79, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20176 [source] Enhancement of crystalline perfection by organic dopants in ZTS, ADP and KHP crystals as investigated by high-resolution XRD and SEMJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2006S. Parthiban To reveal the influence of complexing agents on crystalline perfection, tristhiourea zinc(II) sulfate (ZTS), ammonium dihydrogen phosphate (ADP) and potassium hydrogen phthalate (KHP) crystals grown by slow-evaporation solution growth technique using low concentrations (5 × 10,3M) of dopants like ethylenediamminetetraacetic acid (EDTA) and 1,10-phenanthroline (phen) were characterized by high-resolution X-ray diffractometry (XRD) and scanning electron microscopy (SEM). High-resolution diffraction curves (DCs) recorded for ZTS and ADP crystals doped with EDTA show that the specimen contains an epilayer, as observed by the additional peak in the DC, whereas undoped specimens do not have such additional peaks. On etching the surface layer, the additional peak due to the epilayer disappears and a very sharp DC is obtained, with full width at half-maximum (FWHM) of less than 10,arcsec, as expected from the plane wave dynamical theory of X-ray diffraction for an ideally perfect crystal. SEM micrographs also confirm the existence of an epilayer in doped specimens. The ZTS specimen has a layer with a rough surface morphology, having randomly oriented needles, whereas the ADP specimen contains a layer with dendric structure. In contrast to ADP and ZTS crystals, the DC of phen-doped KHP shows no additional peak, but it is quite broad (FWHM = 28,arcsec) with a high value of integrated intensity, , (area under the DC). The broadness of the DC and the high value of , indicate the formation of a mosaic layer on the surface of the crystal. However, similar to ADP and ZTS, the DC recorded after etching the surface layer of the KHP specimen shows a very sharp peak with an FWHM of 8 arcsec. An SEM photograph of phen-doped KHP shows deep cracks on the surface, confirming the mosaicity. After removing the surface layer, the SEM pictures reveal a smooth surface. A similar trend is observed with other complexing agents, like oxalic acid, bipy and picolinic acid. However, only typical examples are described in the present article where the effects were observed prominently. The investigations on ZTS, ADP and KHP crystals, employing high-resolution XRD and SEM studies, revealed that some organic dopants added to the solution during the growth lead to the formation of a surface layer, due to complexation of these dopants with the trace metal ion impurities present in the solution, which prevents the entry of impurities, including the solvent, into the crystal, thereby assisting crystal growth with high crystalline perfection. The influence of organic dopants on the second harmonic generation efficiency is also investigated. [source] Crystalline morphology and dynamical crystallization of antibacterial ,-polypropylene compositeJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Xin Chen Abstract The crystalline morphology and dynamical crystallization of antibacterial polypropylene composite and pure polypropylene were investigated via differential scanning calorimeter (DSC), wide angle X-ray diffraction (WAXD), and real-time hot-stage optical microscopy (OM). The results reveal that the crystalline morphology of antibacterial PP composites changes with variations of the crystallization conditions and compositions. The crystalline phase consists of both ,-PP and ,-PP crystals. The content of ,-PP decreases with the increase in antibacterial agent content and cooling rate. With the addition of ,-nucleating agent, the morphologies of all dynamically crystallized antibacterial PP composites show no obvious spherulitic morphology, and the decrease of crystal perfection and the increase of nucleation density of antibacterial PP composite system could be observed. With the increase of antibacterial agent content, the overall crystallization rates of the antibacterial PP composite increase dramatically, while the content of ,-PP in all antibacterial PP composite decrease distinctly under given cooling conditions. These results can be explained by the interruptive effect of antibacterial agent on interactions of ,-nucleating agent components and the obstructing effect of antibacterial agent on the mobility of PP chains in melts. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] A11. The influence of the media on eating disordersJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2000S. Almond Background The cause of eating disorders is multifactorial. One of these is sociocultural factors which include family, peers and the media. It has been suggested that constant media pressures can lead to body dissatisfaction, which may result in distorted eating patterns. Aims To review the role of the media in relation to eating disorders Results There has been a shift in the media portrayal of the 'ideal' body size for women, from the voluptuous curved figure of Marilyn Monroe in the 1950s to a thinner 'waif-like' look of Kate Moss in the 1980s. In the mass media shape and weight define perfection. Women perceive themselves as being bigger than they actually are. Their figure deviates from the ideal thus resulting in self body dissatisfaction. 'All I see is these pretty models, I wish I could look like one of them.' ( Wertheim et al. 1997 ) The 'ideal' body image is far from the physiologic norm. Supermodels are born with a specific body type and what the public doesn't understand is that they cannot diet to achieve it. 'Women don't set out to be anorexic, they begin by thinking they're too fat because everywhere they go the media is telling them that they are right' ( Barrett, 1997) Products are often advertised displaying the ideal body shape in the hope that it will enhance the product and create body dissatisfaction. Purchasing the product is perceived as a positive step towards reaching the 'perfect' body image. Concern surrounds the appearance of such advertisements in magazines aimed at adolescent girls, as at this age they are particularly vulnerable to the influences of the media. Stice and Shaw (1994) stated that exposure to the thin 'idea' may have a negative effect on emotions leading to body dissatisfaction. Such emotions include depression, stress, guilt, shame, insecurity, unhappiness, and lower self-confidence. A study by Schotte et al. (1990) indicated that negative emotions can disrupt eating behaviour. Dieters watching a frightening film increased their food intake, whereas nondieters did not. Conclusion The media are not solely responsible for eating disorders but they do contribute by promoting the 'ideal' physique. There is some resistance to media messages, as the majority of people do not develop distorted eating patterns. [source] End-functionalization of semiconducting species with dendronized terpyridine,Ru(II),terpyridine complexesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2009Elefterios K. Pefkianakis Abstract Semiconducting oligomers and polymers decorated with two or one dendronized tpy-Ru(II)-tpy metallocomplexes are presented. Initially, free terpyridine end-functionalized semiconducting oligomers (distyrylanthracene, quinquephenylene, mono- and trifluorenes) were prepared while in a second approach, atom transfer radical polymerization was employed for the preparation of side-chain oligomeric and polymeric (oxadiazole)s using a terpyridine initiator. These terpyridine-bearing oligomers and polymers were complexated with a Percec-type first-generation (G1) dendronized terpyridine,Ru(III)Cl3 monocomplex, having two dodecyloxy groups. All oligomeric and polymeric metallocomplexes were characterized via NMR spectroscopies for their structural perfection and via UV-Vis and PL spectroscopies for their optical properties. The existence of the organic semiconducting blocks in combination with the terpyridine,Ru(II),terpyridine groups afforded hybrid metallo-semiconducting species presenting the optical features of both their components. Moreover, their thin-film morphologies were investigated through atomic force microscopy, revealing, in some cases, an organization tendency in the nanometer scale. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1939,1952, 2009 [source] Superstar Effects in Deluxe Gastronomy , An Empirical Analysis of Value Creation in German Quality RestaurantsKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 4 2009Thomas Ehrmann Summary We analyze whether superstar effects (disproportionate income effects) exist in the deep-pocket market for quality gastronomy in Germany, and what factors determine the stars' rents. In quality gastronomy, the stars can be the restaurant chefs. Building on Rosen's (1981) and Adler's (1985) central theories on star effects, we explore two potential sources of stardom. Following Rosen (1981), we test if quality differences between the chefs' performances have a direct effect on financial rewards ("direct superstar effect"). Following Adler (1985), we assess the income effect of a media presence of chefs ("classical Superstar effect"). Through this, we deal with an economic issue of general interest: does it pay more to develop your skills in your core business to perfection, or to maintain the current level of skills and invest in self-marketing? Analyzing a sample of 288 restaurants, for potential star effects by differences in quality, we find that higher quality increases chefs' revenues. Yet, revenues do not increase disproportionately, and achieving higher quality requires substantial investments in exquisite ingredients, excellent staff and prime ambience. This problem, also called the "agony of the stars", has manifested itself in the bankruptcies of European three-star restaurants in recent years. As regards potential star effects by differences in media presence, we observe a positive impact of TV appearances on financial rewards. Yet, these income effects are moderate as well, so there is neither a direct, nor a classical superstar effect in quality gastronomy. We argue that although both perfection of skills and self-marketing have similarly positive income effects, self-marketing seems both the less risky and the less stressful way to enhance income. [source] Ordering Behavior of Layered Silicate Nanocomposites with a Cylindrical Triblock CopolymerMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 4 2006Chung Ho Lee Abstract Summary: The ordering behavior of the nanocomposites of organically modified montmorillonite (OMMT) with a cylindrical triblock copolymer of polystyrene- block -poly(ethylene- co -butylene)- block -polystyrene (SEBS) has been investigated by temperature-resolved small-angle X-ray scattering (SAXS) and rheometry. X-Ray diffraction (XRD) confirms that the polymer chains are successfully intercalated with the interlayer gallery of the silicates. The data obtained from the SAXS and rheological measurements show that the addition of OMMT leads to a change in the microphase separation behavior of SEBS in the nanocomposites. The molecular interaction between OMMT and the polystyrene (PS) chains of SEBS decreases the structural perfection of the self-assembling, phase-separated domain structure of the nanocomposites. Rheological data exhibit that the order-order (TOOT) and order-disorder transitions (TODT) of the SEBS/OMMT nanocomposites decrease with the addition of OMMT. The highest elongation at break is obtained at approximately 2% OMMT and its further addition to the mixture leads to decreases in tensile strength and elongation. The change in the storage modulus (G,) of a) SEBS, b) S98M2, c) S95M5, and d) S90M10, as a function of temperature in the range of 150,,,T (°C),,,260. [source] | |||||||||||||||||||||||||||||||