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Selected AbstractsA simple algorithm that proves half-integrality of bidirected network programming,NETWORKS: AN INTERNATIONAL JOURNAL, Issue 1 2006Ethan D. Bolker Abstract In a bidirected graph, each end of each edge is independently oriented. We show how to express any column of the incidence matrix as a half-integral linear combination of any column basis, through a simplification, based on an idea of Bolker, of a combinatorial algorithm of Appa and Kotnyek. Corollaries are that the inverse of each nonsingular square submatrix has entries 0, , and ±1, and that a bidirected integral linear program has half-integral solutions. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 48(1), 36,38 2006 [source] Universality at the edge of the spectrum for unitary, orthogonal, and symplectic ensembles of random matricesCOMMUNICATIONS ON PURE & APPLIED MATHEMATICS, Issue 6 2007Percy Deift We prove universality at the edge of the spectrum for unitary (, = 2), orthogonal (, = 1), and symplectic (, = 4) ensembles of random matrices in the scaling limit for a class of weights w(x) = e,V(x) where V is a polynomial, V(x) = ,2mx2m + · · ·, ,2m > 0. The precise statement of our results is given in Theorem 1.1 and Corollaries 1.2 and 1.4 below. For the same class of weights, a proof of universality in the bulk of the spectrum is given in [12] for the unitary ensembles and in [9] for the orthogonal and symplectic ensembles. Our starting point in the unitary case is [12], and for the orthogonal and symplectic cases we rely on our recent work [9], which in turn depends on the earlier work of Widom [46] and Tracy and Widom [42]. As in [9], the uniform Plancherel-Rotach-type asymptotics for the orthogonal polynomials found in [12] plays a central role. The formulae in [46] express the correlation kernels for , = 1, 4 as a sum of a Christoffel-Darboux (CD) term, as in the case , = 2, together with a correction term. In the bulk scaling limit [9], the correction term is of lower order and does not contribute to the limiting form of the correlation kernel. By contrast, in the edge scaling limit considered here, the CD term and the correction term contribute to the same order: this leads to additional technical difficulties over and above [49]. © 2006 Wiley Periodicals, Inc. [source] A Tale of Two VectorsDIALECTICA, Issue 4 2009Marc Lange Why (according to classical physics) do forces compose according to the parallelogram of forces? This question has been controversial; it is one episode in a longstanding, fundamental dispute regarding which facts are not to be explained dynamically. If the parallelogram law is explained statically, then the laws of statics are separate from and (in an important sense) "transcend" the laws of dynamics. Alternatively, if the parallelogram law is explained dynamically, then statical laws become mere corollaries to the dynamical laws. I shall attempt to trace the history of this controversy in order to identify what it would be for one or the other of these rival views to be correct. I shall argue that various familiar accounts of natural law (Lewis's Best System Account, laws as contingent relations among universals, and scientific essentialism) not only make it difficult to see what the point of this dispute could have been, but also improperly foreclose some serious scientific options. I will sketch an alternative account of laws (including what their necessity amounts to and what it would be for certain laws to "transcend" others) that helps us to understand what this dispute was all about. [source] Agency in the Discursive ConditionHISTORY AND THEORY, Issue 4 2001Elizabeth Deeds Ermarth This article claims that postmodernity necessarily, and perhaps opportunely, undermines the bases upon which political democracy traditionally has rested; and that therefore some significant work must be done in order to redefine, restore, or otherwise reconfigure democratic values and institutions for a changed cultural condition. This situation presents the opportunity to explore the new options, positive openings, and discursive opportunities that postmodernity presents for political practice; for this the problem of agency provides a focal issue. The practices of postmodernity, taken together, represent substantial challenges, not just to this or that cherished habit, but to modernity itself and all its corollaries, including its inventions of objectivity, of "the individual" (miserable treasure), and of all the related values (project, capital, consensus and, above all, neutrality) which still underwrite so much of what we do as citizens, consumers, and professionals not to mention as more private persons, parents, and partners. Fortunately, postmodernity does not demolish all our most cherished beliefs, values, and practices; but it does require recognition of how those beliefs, values, and practices actually function and of what alternatives they suppress. [source] Improved bounds for the chromatic number of a graphJOURNAL OF GRAPH THEORY, Issue 3 2004S. Louis Hakimi Abstract After giving a new proof of a well-known theorem of Dirac on critical graphs, we discuss the elegant upper bounds of Matula and Szekeres-Wilf which follow from it. In order to improve these bounds, we consider the following fundamental coloring problem: given an edge-cut (V1, V2) in a graph G, together with colorings of ,V1, and ,V2,, what is the least number of colors in a coloring of G which "respects" the colorings of ,V1, and ,V2, ? We give a constructive optimal solution of this problem, and use it to derive a new upper bound for the chromatic number of a graph. As easy corollaries, we obtain several interesting bounds which also appear to be new, as well as classical bounds of Dirac and Ore, and the above mentioned bounds of Matula and Szekeres-Wilf. We conclude by considering two algorithms suggested by our results. © 2004 Wiley Periodicals, Inc. J Graph Theory 47: 217,225, 2004 [source] Connected (g, f)-factorsJOURNAL OF GRAPH THEORY, Issue 1 2002M. N. Ellingham Abstract In this paper we study connected (g, f)-factors. We describe an algorithm to connect together an arbitrary spanning subgraph of a graph, without increasing the vertex degrees too much; if the algorithm fails we obtain information regarding the structure of the graph. As a consequence we give sufficient conditions for a graph to have a connected (g, f)-factor, in terms of the number of components obtained when we delete a set of vertices. As corollaries we can derive results of Win [S. Win, Graphs Combin 5 (1989), 201,205], Xu et al. [B. Xu, Z. Liu, and T. Tokuda, Graphs Combin 14 (1998), 393,395] and Ellingham and Zha [M. N. Ellingham and Xiaoya Zha, J Graph Theory 33 (2000), 125,137]. We show that a graph has a connected [a, b]-factor (b>a,,,2) if the graph is tough enough; when b,,,a,+,2, toughness at least suffices. We also show that highly edge-connected graphs have spanning trees of relatively low degree; in particular, an m -edge-connected graph G has a spanning tree T such that degT (,),,,2,+,, degG(,)/m, for each vertex ,. © 2002 John Wiley & Sons, Inc. J Graph Theory 39: 62,75, 2002 [source] A new method for scoring additive multi-attribute value models using pairwise rankings of alternativesJOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 3-4 2008Paul Hansen Abstract We present a new method for determining the point values for additive multi-attribute value models with performance categories. The method, which we refer to as PAPRIKA (Potentially All Pairwise RanKings of all possible Alternatives), involves the decision-maker pairwise ranking potentially all undominated pairs of all possible alternatives represented by the value model. The number of pairs to be explicitly ranked is minimized by the method identifying all pairs implicitly ranked as corollaries of the explicitly ranked pairs. We report on simulations of the method's use and show that if the decision-maker explicitly ranks pairs defined on just two criteria at-a-time, the overall ranking of alternatives produced by the value model is very highly correlated with the true ranking. Therefore, for most practical purposes decision-makers are unlikely to need to rank pairs defined on more than two criteria, thereby reducing the elicitation burden. We also describe a successful real-world application involving the scoring of a value model for prioritizing patients for cardiac surgery in New Zealand. We conclude that although the new method entails more judgments than traditional scoring methods, the type of judgment (pairwise rankings of undominated pairs) is arguably simpler and might reasonably be expected to reflect the preferences of decision-makers more accurately. Copyright © 2009 John Wiley & Sons, Ltd. [source] The non-Gaussian nature of bibliometric and scientometric distributions: A new approach to interpretationJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 13 2001Ludmila E. Ivancheva An attempt has been made to give an answer to the question: Why do most bibliometric and scientometric laws reveal characters of Non-Gaussian distributions, i.e., have unduly long "tails"? We tried to apply the approach of the so-called "Universal Law," discovered by G. Stankov (1997, 1998). The basic principle we have used here is that of the reciprocity of energy and space. A new "wave concept" of scientific information has been propounded, in which terms the well-known bibliometric and scientometric distributions find a rather satisfactory explanation. One of the made corollaries is that , = 1 is the most reasonable value for the family of Zipf laws, applied to information or social phenomena. [source] Separation and divergence: The untold story of James Robertson's and John Bowlby's theoretical dispute on mother,child separationJOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES, Issue 3 2009Frank C. P. van der Horst The work of Robertson and Bowlby is generally seen as complementary, Robertson being the practically oriented observer and Bowlby focusing on theoretical explanations for Robertson's observations. The authors add to this picture an "untold story" of the collaboration between Robertson and Bowlby: the dispute between the two men that arose in the 1960s about the corollaries of separation and the ensuing personal animosity. On the basis of unique archival materials, this until now little known aspect of the history of attachment theory is extensively documented. The deteriorating relationship between Robertson and Bowlby is described against the background of different currents in psychoanalysis in Britain in the interbellum. © 2009 Wiley Periodicals, Inc. [source] Effects of radio-collars on European badgers (Meles meles)JOURNAL OF ZOOLOGY, Issue 1 2002F. A. M. Tuyttens Abstract The relationships between radio-collaring/tracking and 12 biometric parameters in a population of badgers (Meles meles) that were live-trapped in south-west England were investigated. The length of time for which a badger had worn a radio-collar was selected as an explanatory variable in generalized linear models of three biometric parameters (body condition, body weight and testes volume) irrespective of whether or not age class was included as a variable in the analyses. There was evidence that badgers that had been carrying a radio-collar for 1,100 days had lower body condition scores both when compared to badgers that had not been collared and with those that had been collared for longer than 100 days, suggesting a post-collaring acclimation period. In addition, the time period between first and last capture was longer for radio-collared than non-collared badgers. It is unlikely that this was due to an effect of collaring on trappability or to non-random selection of badgers for collaring. Although testes size differed between non-collared badgers and badgers that had been tagged for > 100 days, the relationship between radio-collaring and reproductive output remained unproven. These results highlight not only the need to assess the welfare aspects of radio-collaring but also the potential intricacy of corollaries of collaring. Explorations such as that reported here are important to the validity of studies that make use of radio-telemetry. [source] On the domain dependence of solutions to the compressible Navier,Stokes equations of a barotropic fluidMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 12 2002Eduard Feireisl We prove a general compactness result for the solution set of the compressible Navier,Stokes equations with respect to the variation of the underlying spatial domain. Among various corollaries, we then prove a general existence theorem for the system in question with no restrictions on smoothness of the spatial domain. Copyright © 2002 John Wiley & Sons, Ltd. [source] Parametrized Littlewood,Paley operators on Hardy and weak Hardy spacesMATHEMATISCHE NACHRICHTEN, Issue 4 2007Yong Ding Abstract In this paper, we give the boundedness of the parametrized Littlewood,Paley function on the Hardy spaces and weak Hardy spaces. As the corollaries of the above results, we prove that is of weak type (1, 1) and of type (p, p) for 1 < p < 2, respectively. This results are substantial improvement and extension of some known results. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] ON THE STRONG LAW OF LARGE NUMBERS UNDER REARRANGEMENTS FOR SEQUENCES OF BLOCKWISE ORTHOGONAL RANDOM ELEMENTS IN BANACH SPACESAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 4 2007Nguyen Van Quang Summary The condition of the strong law of large numbers is obtained for sequences of random elements in type p Banach spaces that are blockwise orthogonal. The current work extends a result of Chobanyan & Mandrekar (2000)[On Kolmogorov SLLN under rearrangements for orthogonal random variables in a B -space. J. Theoret. Probab. 13, 135,139.] Special cases of the main results are presented as corollaries, and illustrative examples are provided. [source] Gene expression profiling of the ageing rat vibrissa follicleBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2005C-L. Yang Summary Background, The application of gene expression profiling to the study of chronological ageing has the potential to illuminate the molecular mechanisms underlying a complex and active process. For example, ageing of the skin and its constituent organs has myriad phenotypic consequences, and a better understanding of the means by which these changes arise has important corollaries for intervention strategies. Objectives, We used a transcriptional profiling approach to investigate changes in gene expression associated with ageing of the large vibrissa follicle of the Wistar rat. Methods, Follicle mRNA isolated from male Wistar rats at 1 and 18 months of age was hybridized to Clontech Atlas 1.2 Rat cDNA macroarrays. Confirmation of array results was provided by the use of Northern blotting and immunohistochemistry. Results, Seven transcripts displayed at least a 1·6-fold increase in expression with age, of which APOD (2·5-fold), GSTM2 (2·0-fold) and NPY (1·8-fold) showed the greatest increases. Decreased expression was found in 19 transcripts, most notably in ALOX12 (13·3-fold) and GAP43 (12·6-fold) expression. Conclusions, Follicular ageing is characterized by transcriptional changes associated with diverse aspects of keratinocyte metabolism, proliferation and development. [source] Pituitary and autonomic responses to cold exposures in manACTA PHYSIOLOGICA, Issue 4 2005J. Leppäluoto Abstract This review presents hormonal responses to various cold exposures and their calorigenic effects in man and some animals. Previous studies in rats have shown that cold exposures activate the hypothalamic-pituitary-thyroid axis. Increased thyroid hormone concentrations lead to heat production via general stimulation of metabolism (obligatory thermogenesis) and possibly via activation of thyroid hormone receptors and uncoupling protein 1 (UCP 1) and deiodinase enzyme genes in the brown adipose tissue (BAT). In human subjects long-term cold exposures do not seem to activate the pituitary-thyroid axis, but rather accelerate the elimination of triiodothyronine (T3), leading to low serum concentrations of free T3 hormone. In corollary to this a hypothyreotic condition with increased serum thyroid-stimulating hormone and impaired mood and cognitive performance can be observed after long-term cold exposures such as wintering. During cold exposures the sympathetic nerve system is activated and noradrenaline is released to blood circulation and to BAT, where it leads to production of cAMP, lipolysis and free fatty acids. Free fatty acids open the mitochondrial proton channel protein in BAT. Protons enter the mitochondria and inhibit ATP synthesis (uncoupling). By this way energy is transformed into heat (facultatory or adaptive thermogenesis). In adult human subjects the amount of BAT is small and adaptive thermogenesis (non-shivering thermogenesis) has a smaller role. UCP 1 with other uncoupling proteins may have other functions in the control of body weight, sugar balance and formation of reactive oxygen species. [source] The Livelihoods Gap: Responding to the Economic Dynamics of Vulnerability in SomaliaDISASTERS, Issue 1 2002Andre Le Sage A ,livelihoods gap' has become evident in international aid delivery to Somalia. Existing aid interventions do not address the economic dynamics of vulnerability resulting from Somalia's long history of predatory development and asset stripping. To prevent poor households' regular return to sub-subsistence income levels after a brief period of plenty, this paper argues that aid agencies should reorient and expand existing interventions to assist poor households to capitalise on temporary improvements in environmental and security conditions. As a corollary to emergency relief and efforts to construct state institutions, it is necessary to devise country-wide interventions that will rebuild household asset bases by protecting savings during times of stress and ensuring that markets benefit poor producers. [source] crabp and maf highlight the novelty of the amphioxus club-shaped glandACTA ZOOLOGICA, Issue 2 2004William R. Jackman Abstract The club-shaped gland (csg) is a prominent organ during the development of amphioxus. However, the evolutionary significance of this pharyngeal structure has been a mystery because of the lack of an obvious corollary in vertebrates or other close relatives. To address the homology of the csg by molecular means, we report the cloning and expression patterns of two amphioxus genes expressed during its development, crabp and maf. Amphioxus maf is a bzip transcription factor expressed early in csg formation in the forming of the ventral duct of the gland. crabp encodes a cellular retinoic acid binding protein and is expressed widely in the csg later in its development. We compare these genes to the expression of AmphiKrox, a zinc-finger transcription factor previously reported to be expressed during csg development. Together these genes mark different spatial and temporal aspects of csg formation. However, we find little evidence to suggest homology of the csg with other organs in amphioxus or other chordates. We therefore propose that the csg can be viewed as an evolutionary novelty that probably arose within the amphioxus lineage. [source] Strongly Consistent Self-Confirming EquilibriumECONOMETRICA, Issue 2 2010Yuichiro Kamada Fudenberg and Levine (1993a) introduced the notion of self-confirming equilibrium, which is generally less restrictive than Nash equilibrium. Fudenberg and Levine also defined a concept of consistency, and claimed in their Theorem 4 that with consistency and other conditions on beliefs, a self-confirming equilibrium has a Nash equilibrium outcome. We provide a counterexample that disproves Theorem 4 and prove an alternative by replacing consistency with a more restrictive concept, which we call strong consistency. In games with observed deviators, self-confirming equilibria are strongly consistent self-confirming equilibria. Hence, our alternative theorem ensures that despite the counterexample, the corollary of Theorem 4 is still valid. [source] Social Polarization and the Politics of Low Income Mortgage Lending in the United StatesGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3 2003Jason Hackworth ABSTRACT The structured inequalities of capital investment and disinvestment are prominent themes in critical urban and regional research, but many accounts portray ,capital' as a global, faceless and placeless abstraction operating according to a hidden, unitary logic. Sweeping political-economic shifts in the last generation demonstrate that capital may shape urban and regional processes in many different ways, and each of these manifestations creates distinct constraints and opportunities. In this paper, we analyze a new institutional configuration in the USA that is reshaping access to wealth among the poor , a policy ,consensus' to expand home-ownership among long-excluded populations. This shift has opened access to some low- and moderate-income households, and racial and ethnic minorities, but the necessary corollary is a greater polarization between those who are able to own and those who are not. We provide a critical analysis of these changes, drawing on national housing finance statistics as well as a multivariate analysis of differences between owners and renters in the 1990s in New York City. As home-ownership strengthens its role as a privatized form of stealth urban and housing policy in the USA, its continued expansion drives a corresponding reconstruction of its value for different groups, and inscribes a sharper axis of property-rights inequalities among owners and renters in the working classes. [source] On strike-slip faulting in layered mediaGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2002Maurizio Bonafede Summary We study the effects of structural inhomogeneities on the stress and displacement fields induced by strike-slip faults in layered media. An elastic medium is considered, made up of an upper layer bounded by a free surface and welded to a lower half-space characterized by different elastic parameters. Shear cracks with assigned stress drop are employed as mathematical models of strike-slip faults, which are assumed to be vertical and planar. If the crack is entirely embedded within the lower medium (case A), a Cauchy-kernel integral equation is obtained, which is solved by employing an expansion of the dislocation density in Chebyshev polynomials. If the crack is within the lower medium but it terminates at the interface (case B), a generalized Cauchy singularity appears in the integral kernel. This singularity affects the singular behaviour of the dislocation density at the crack tip touching the interface. Finally, the case of a crack crossing the interface is considered (case C). The crack is split into two interacting sections, each placed in a homogeneous medium and both open at the interface. Two coupled generalized Cauchy equations are obtained and solved for the dislocation density distribution of each crack section. An asymptotic study near the intersection between the crack and the interface shows that the dislocation densities for each crack section are bounded at the interface, where a jump discontinuity is present. As a corollary, the stress drop must be discontinuous at the interface, with a jump proportional to the rigidity contrast between the adjoining media. This finding is shown to have important implications for the development of geometrical complexities within transform fault zones: planar strike-slip faults cutting across layer discontinuities with arbitrary stress drop values are shown to be admissible only if the interface between different layers becomes unwelded during the earthquake at the crack/interface junction. Planar strike-slip faulting may take place only in mature transform zones, where a repetitive earthquake cycle has already developed, if the rheology is perfectly elastic. Otherwise, the fault cannot be planar: we infer that strike-slip faulting at depth is plausibly accompanied by en-echelon surface breaks in a shallow sedimentary layer (where the stress drop is lower than prescribed by the discontinuity condition), while ductile deformation (or steady sliding) at depth may be accommodated by multiple fault branching or by antithetic faulting in the upper brittle layer (endowed with lower rigidity but higher stress). [source] Desertification in the Sahel: a reinterpretation of a reinterpretationGLOBAL CHANGE BIOLOGY, Issue 7 2007STEPHEN D. PRINCE Abstract In semiarid regions the ratio of annual net primary production to precipitation, rain-use efficiency (RUE), has been used as an index of desertification. In a recent publication (Hein & de Ridder, 2006) it was proposed that an incorrect understanding of the relationship between RUE and rainfall has led to a misinterpretation of the satellite record of desertification in the African Sahel. Here, we examine this suggestion and show that, contrary to Hein and de Ridder's statement, satellite studies of Sahelian RUE have reported increases, decreases, and constant values since 1981. Furthermore, we find that data do not support their proposal that RUE increases with rainfall, even in nondegraded areas. Hence we reject their corollary, that constant RUE is prima facie evidence of desertification. The fundamental difficulty with the use of RUE for detection of desertification remains, that is the difficulty of estimation of the RUE for nondegraded land at a regional scale. [source] 3. HISTORIOGRAPHY WITHOUT GOD: A REPLY TO GREGORY,HISTORY AND THEORY, Issue 4 2008TOR EGIL FØRLAND ABSTRACT This reply aims both to respond to Gregory and to move forward the debate about God's place in historiography. The first section is devoted to the nature of science and God. Whereas Gregory thinks science is based on metaphysical naturalism with a methodological corollary of critical-realist empiricism, I see critical, empiricist methodology as basic, and naturalism as a consequence. Gregory's exposition of his apophatic theology, in which univocity is eschewed, illustrates the fissure between religious and scientific worldviews,no matter which basic scientific theory one subscribes to. The second section is allotted to miracles. As I do, Gregory thinks no miracle occurred on Fox Lakes in 1652, but he restricts himself to understanding the actors and explaining change over time, and refuses to explain past or contemporary actions and events. Marc Bloch, in his book The Royal Touch: Sacred Monarchy and Scrofula in England and France, is willing to go much further than Gregory. Using his superior medical knowledge to substitute his own explanation of the phenomenon for that of the actors, Bloch dismisses the actors' beliefs that they or others had been miraculously cured, and explains that they believed they saw miraculous healing because they were expecting to see it. In the third section, on historical explanation, I rephrase the question whether historians can accommodate both believers in God and naturalist scientists, asking whether God, acting miraculously or not, can be part of the ideal explanatory text. I reply in the negative, and explicate how the concept of a plural subject suggests how scientists can also be believers. This approach may be compatible with two options presented by Peter Lipton for resolving the tension between religion and science. The first is to see the truth claims of religious texts as untranslatable into scientific language (and vice versa); the other is to immerse oneself in religious texts by accepting them as a guide but not believing in their truth claims when these contradict science. [source] Augmented Lyapunov functional and delay-dependent stability criteria for neutral systemsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 18 2005Yong He Abstract In this paper, an augmented Lyapunov functional is proposed to investigate the asymptotic stability of neutral systems. Two methods with or without decoupling the Lyapunov matrices and system matrices are developed and shown to be equivalent to each other. The resulting delay-dependent stability criteria are less conservative than the existing ones owing to the augmented Lyapunov functional and the introduction of free-weighting matrices. The delay-independent criteria are obtained as an easy corollary. Numerical examples are given to demonstrate the effectiveness and less conservativeness of the proposed methods. Copyright © 2005 John Wiley & Sons, Ltd. [source] Vertical Social Differentiation in Athens: Alternative or Complement to Community Segregation?INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 4 2001Thomas Maloutas Vertical social differentiation is presented in the recent literature as an important element of reduced segregation in South European cities, and the supporting evidence originates mainly from Athens. The authors of this article question the claim about the common form and function of vertical social differentiation across South Europe, as well as its opposition to community segregation, and try to reveal the specificity of the processes leading to its formation in Athens. Since the mid-1970s, the dominant process of urban growth in Athens has been middle-class suburbanization. This process has reinforced community segregation and, at the same time, has triggered a filtering-down process in wide areas around the CBD, formerly occupied by upper and mainly intermediate professional categories. Interclass vertical segregation has subsequently appeared in these areas, where intermediate professional categories and lower middle-class households are now predominant. The fact that these areas do not represent a real choice for any of their resident groups shows that this vertical cohabitation has been the unintended consequence of changing segregation patterns, and hardly the outcome or the corollary of a growing process of sociospatial homogenization. Dans les textes récents, la différenciation sociale verticale est présentée comme un facteur important dans la réduction de la ségrégation urbaine en Europe du Sud, les éléments probants provenant essentiellement d'Athènes. Cet article conteste l'idée que la différenciation sociale verticale ait une forme ou une fonction commune en Europe méridionale, et qu'elle entrave la ségrégation horizontale; de plus, il tente d'exposer la spécificité des processus qui conduisent à sa formation à Athènes. Depuis le milieu des années 1970, l'expansion urbaine de la capitale grecque se caractérise par l'implantation en banlieue des classes supérieurs et moyennes. Ce processus a renforcé la ségrégation dans les quartiers et, parallèlement, a déclenché un processus de filtrage vers le bas dans de vastes zones entourant l'hypercentre, précédemment occupées par des catégories de professionnels libéraux supérieures et surtout moyennes. Une ségrégation verticale interclasse est ensuite apparue dans ces quartiers, des catégories de libéraux moyennes et des ménages de la petite bourgeoisie y prédominant désormais. Or, quel que soit le groupe de résidents, ces zones ne représentent pas un choix réel; cette cohabitation verticale est donc bien la conséquence imprévue de la modification des schémas de ségrégation, plutôt que le résultat ou le corollaire d'une homogénéisation socio-spatiale accentuée. [source] Changing sources of support for women's political rights*INTERNATIONAL SOCIAL SCIENCE JOURNAL, Issue 184 2005Katherine Meyer Much research investigating changes in women's political rights focuses on the presence or absence of improvement that is evident in national and international policies or on gender proportionality in representative institutions at international, national, and local levels. Public opinion about women's rights is an important corollary to this research because it underpins the legitimacy of policies and representative bodies. However, if examined alone, changes in public opinion over time yield an incomplete picture of women's situation, just as changes in policies and representation do. Factors that lie behind statistics about trends in women's rights matter, and it is essential to figure out if the sources of support for women's political rights shift over time. We employed data from Kuwait in the years surrounding the Beijing +5 conference to illustrate how the absence of change in public opinion about women's rights can hide important social dynamics that figure into the development of policies and practices affecting women. Whereas support for women's rights was evident among the most numerous and advantaged Kuwaiti citizens in 1994, it rested less with the general public and more with citizens involved in social networks and those who had particular political and cultural agendas by 1998. [source] Floating without flotations,the exchange rate and the Mexican stock market: 1995,2001JOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 3 2006Jesús Muñoz Abstract Pegged exchange rates in capital importing countries partially ,socialised' the risks of international borrowing. A corollary of managed floating, therefore, is a reallocation of risk bearing to private capital markets. Equity finance offers explicit risk sharing but Mexican experience since 1995 confirms that it may not expand spontaneously under a floating regime, despite buoyant international conditions. As an explanation for this disappointing outcome, the analysis highlights the implications of managed floating for equity demand when corporate debt is high. Policy must recognize that while firms need to reduce gearing, investors may not be attracted to the shares of indebted companies. Copyright © 2006 John Wiley & Sons, Ltd. [source] Modelling of mineral equilibria in ultrahigh-temperature metamorphic rocks from the Anápolis,Itauçu Complex, central BrazilJOURNAL OF METAMORPHIC GEOLOGY, Issue 7 2005J. A. BALDWIN Abstract A new quantitative approach to constraining mineral equilibria in sapphirine-bearing ultrahigh-temperature (UHT) granulites through the use of pseudosections and compatibility diagrams is presented, using a recently published thermodynamic model for sapphirine. The approach is illustrated with an example from an UHT locality in the Anápolis,Itauçu Complex, central Brazil, where modelling of mineral equilibria indicates peak metamorphic conditions of about 9 kbar and 1000 °C. The early formed, coarse-grained assemblage is garnet,orthopyroxene,sillimanite,quartz, which was subsequently modified following peak conditions. The retrograde pressure,temperature (P,T) path of this locality involves decompression across the FeO,MgO,Al2O3,SiO2 (FMAS) univariant reaction orthopyroxene + sillimanite = garnet + sapphirine + quartz, resulting in the growth of sapphirine,quartz, followed by cooling and recrossing of this reaction. The resulting microstructures are modelled using compatibility diagrams, and pseudosections calculated for specific grain boundaries considered as chemical domains. The sequence of microstructures preserved in the rocks constrains a two-stage isothermal decompression,isobaric cooling path. The stability of cordierite along the retrograde path is examined using a domainal approach and pseudosections for orthopyroxene,quartz and garnet,quartz grain boundaries. This analysis indicates that the presence or absence of cordierite may be explained by local variation in aH2O. This study has important implications for thermobarometric studies of UHT granulites, mainly through showing that traditional FMAS petrogenetic grids based on experiments alone may overestimate P,T conditions. Such grids are effectively constant aH2O sections in FMAS-H2O (FMASH), for which the corresponding aH2O is commonly higher than that experienced by UHT granulites. A corollary of this dependence of mineral equilibria on aH2O is that local variations in aH2O may explain the formation of cordierite without significant changes in P,T conditions, particularly without marked decompression. [source] THE MESOZOIC RADIATION OF EUKARYOTIC ALGAE: THE PORTABLE PLASTID HYPOTHESIS,JOURNAL OF PHYCOLOGY, Issue 2 2003Daniel Grzebyk Although all chloroplasts appear to have been derived from a common ancestor, a major schism occurred early in the evolution of eukaryotic algae that gave rise to red and green photoautotrophic lineages. In Paleozoic and earlier times, the fossil record suggests that oceanic eukaryotic phytoplankton were dominated by the green (chl b -containing) algal line. However, following the end-Permian extinction, a diverse group of eukaryotic phytoplankton evolved from secondary symbiotic associations in the red (chl c -containing) line and subsequently rose to ecological prominence. In the contemporary oceans, red eukaryotic phytoplankton taxa continue to dominate marine pelagic food webs, whereas the green line is relegated to comparatively minor ecological and biogeochemical roles. To help elucidate why the oceans are not dominated by green taxa, we analyzed and compared whole plastid genomes in both the red and green lineages. Our results suggest that whereas all algal plastids retain a core set of genes, red plastids retain a complementary set of genes that potentially confer more capacity to autonomously express proteins regulating oxygenic photosynthetic and energy transduction pathways. We hypothesize that specific gene losses in the primary endosymbiotic green plastid reduced its portability for subsequent symbiotic associations. This corollary of the plastid "enslavement" hypothesis may have limited subsequent evolutionary advances in the green lineage while simultaneously providing a competitive advantage to the red lineage. [source] Existence of a Condorcet Winner When Voters Have Other-Regarding PreferencesJOURNAL OF PUBLIC ECONOMIC THEORY, Issue 5 2010SANJIT DHAMI In standard political economy models, voters are "self-interested" that is, care only about "own" utility. However, the emerging evidence indicates that voters often have "other-regarding preferences" (ORP), that is, in deciding among alternative policies voters care about their payoffs relative to others. We extend a widely used general equilibrium framework in political economy to allow for voters with ORP, as in Fehr and Schmidt (1999). In line with the evidence, these preferences allow voters to exhibit "envy" and "altruism," in addition to the standard concern for "own utility." We give sufficient conditions for the existence of a Condorcet winner when voters have ORP. This could open the way for an incorporation of ORP in a variety of political economy models. Furthermore, as a corollary, we give more general conditions for the existence of a Condorcet winner when voters have purely selfish preferences. [source] Assessing interaction effects in linear measurement error modelsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 1 2005Li-Shan Huang Summary., In a linear model, the effect of a continuous explanatory variable may vary across groups defined by a categorical variable, and the variable itself may be subject to measurement error. This suggests a linear measurement error model with slope-by-factor interactions. The variables that are defined by such interactions are neither continuous nor discrete, and hence it is not immediately clear how to fit linear measurement error models when interactions are present. This paper gives a corollary of a theorem of Fuller for the situation of correcting measurement errors in a linear model with slope-by-factor interactions. In particular, the error-corrected estimate of the coefficients and its asymptotic variance matrix are given in a more easily assessable form. Simulation results confirm the asymptotic normality of the coefficients in finite sample cases. We apply the results to data from the Seychelles Child Development Study at age 66 months, assessing the effects of exposure to mercury through consumption of fish on child development for females and males for both prenatal and post-natal exposure. [source] | ||||||||||||||||||||||||||||||||||||||||||||||