1,777 research outputs found

    Long-Lived Non-Equilibrium Interstitial-Solid-Solutions in Binary Mixtures

    Get PDF
    We perform particle resolved experimental studies on the heterogeneous crystallisation process of two compo- nent mixtures of hard spheres. The components have a size ratio of 0.39. We compared these with molecular dynamics simulations of homogenous nucleation. We find for both experiments and simulations that the final assemblies are interstitial solid solutions, where the large particles form crystalline close-packed lattices, whereas the small particles occupy random interstitial sites. This interstitial solution resembles that found at equilibrium when the size ratios are 0.3 [Filion et al., Phys. Rev. Lett. 107, 168302 (2011)] and 0.4 [Filion, PhD Thesis, Utrecht University (2011)]. However, unlike these previous studies, for our system sim- ulations showed that the small particles are trapped in the octahedral holes of the ordered structure formed by the large particles, leading to long-lived non-equilibrium structures in the time scales studied and not the equilibrium interstitial solutions found earlier. Interestingly, the percentage of small particles in the crystal formed by the large ones rapidly reaches a maximum of around 14% for most of the packing fractions tested, unlike previous predictions where the occupancy of the interstitial sites increases with the system concentration. Finally, no further hopping of the small particles was observed

    The End of the Constitutionalism-Democracy Debate

    Get PDF
    There is something strange about the literature produced in the 1990s by North American constitutional theorists on the relationship between constitutionalism and democracy. The problem, I believe, has two different roots: an excessive focus on the legitimacy of judicial review and an insistence in defending the constitutional status quo. On the one hand, the emphasis on judicial review usually ended up obscuring what should have been at the center of the debate: the way in which ordinary citizens could or not re-constitute the fundamental laws under which they lived. On the other, these approaches rarely involved recommendations for institutional changes (other than the occasional proposal for the abolition of judicial review) in the constitutional regimes they were operating. These \u27happy endings\u27 were particularly surprising, since one would think there must be many ways of upsetting the \u27balance\u27 between constitutionalism and democracy in favor of the latter. In fact, it would be astonishing that constitutional traditions which originated in an attempt to protect certain institutions from the passions of disorganized multitudes would not be wanting, even a bit, from the point of view of democracy. With these limited ends, it is no surprise that the constitutionalism-democracy debate appears to have stagnated. This paper will advance a different approach to the debate, one that emphasizes popular participation in constitutional change and that recommends institutional transformations that would contribute to the realization of democracy in contemporary constitutional systems. I begin by reviewing the works of Ronald Dworkin, Jeremy Waldron, and Bruce Ackerman. The take of these three authors on majority rule, judicial review, and constitutional amendments, exemplify very well the shortcomings of the literature on constitutionalism and democracy. The implications of Dworkin\u27s constitutional theory are fatal for any democratic project: the prettification of a constitutional regime that is reputed to rest on the \u27right\u27 abstract principles. Waldron\u27s approach, although attributing to \u27the people\u27 the right to have the constitution they want, ends up identifying people and legislature, thus neglecting any actual participation of citizens in constitutional change. Ackerman\u27s constitutional politics, although insisting in keeping citizens and representatives separate, replaces the flesh and blood human beings that live under the constitutional regime with a mythical \u27People\u27 (always with a capital P) whose acts are identified ex post facto. In contrast to these theories, I propose a conception of constitutionalism according to which the constitution should remain permanently open to important transformations. Under this \u27weak\u27 constitutionalism, there is no such thing as a \u27good\u27 or \u27finished\u27 constitution, contrary to what Dworkin\u27s analysis implies. Only such a conception of constitutionalism, I believe, is consistent with a serious commitment to the democratic ideal. However, this supposes that democracy is not exhausted in legislatures and daily governance, but that it extends to deliberating and deciding on the very content of the constitution. In this respect, and in contrast to Waldron, I will defend a distinction between two dimensions of the democratic ideal: democracy at the level of daily governance and democracy at the level of the fundamental laws. By their very nature (daily vs. episodical), each of these dimensions demand different levels of popular engagement. Finally, I consider the institutional implications of this approach to the constitutionalism-democracy dilemma. Unlike Ackerman, I suggest a series of mechanisms designed to allow for the actual participation of ordinary citizens in the constitution and re-constitution of government

    The End of the Constitutionalism-Democracy Debate

    Get PDF
    There is something strange about the literature produced in the 1990s by North American constitutional theorists on the relationship between constitutionalism and democracy. The problem, I believe, has two different roots: an excessive focus on the legitimacy of judicial review and an insistence in defending the constitutional status quo. On the one hand, the emphasis on judicial review usually ended up obscuring what should have been at the center of the debate: the way in which ordinary citizens could or not re-constitute the fundamental laws under which they lived. On the other, these approaches rarely involved recommendations for institutional changes (other than the occasional proposal for the abolition of judicial review) in the constitutional regimes they were operating. These \u27happy endings\u27 were particularly surprising, since one would think there must be many ways of upsetting the \u27balance\u27 between constitutionalism and democracy in favor of the latter. In fact, it would be astonishing that constitutional traditions which originated in an attempt to protect certain institutions from the passions of disorganized multitudes would not be wanting, even a bit, from the point of view of democracy. With these limited ends, it is no surprise that the constitutionalism-democracy debate appears to have stagnated. This paper will advance a different approach to the debate, one that emphasizes popular participation in constitutional change and that recommends institutional transformations that would contribute to the realization of democracy in contemporary constitutional systems. I begin by reviewing the works of Ronald Dworkin, Jeremy Waldron, and Bruce Ackerman. The take of these three authors on majority rule, judicial review, and constitutional amendments, exemplify very well the shortcomings of the literature on constitutionalism and democracy. The implications of Dworkin\u27s constitutional theory are fatal for any democratic project: the prettification of a constitutional regime that is reputed to rest on the \u27right\u27 abstract principles. Waldron\u27s approach, although attributing to \u27the people\u27 the right to have the constitution they want, ends up identifying people and legislature, thus neglecting any actual participation of citizens in constitutional change. Ackerman\u27s constitutional politics, although insisting in keeping citizens and representatives separate, replaces the flesh and blood human beings that live under the constitutional regime with a mythical \u27People\u27 (always with a capital P) whose acts are identified ex post facto. In contrast to these theories, I propose a conception of constitutionalism according to which the constitution should remain permanently open to important transformations. Under this \u27weak\u27 constitutionalism, there is no such thing as a \u27good\u27 or \u27finished\u27 constitution, contrary to what Dworkin\u27s analysis implies. Only such a conception of constitutionalism, I believe, is consistent with a serious commitment to the democratic ideal. However, this supposes that democracy is not exhausted in legislatures and daily governance, but that it extends to deliberating and deciding on the very content of the constitution. In this respect, and in contrast to Waldron, I will defend a distinction between two dimensions of the democratic ideal: democracy at the level of daily governance and democracy at the level of the fundamental laws. By their very nature (daily vs. episodical), each of these dimensions demand different levels of popular engagement. Finally, I consider the institutional implications of this approach to the constitutionalism-democracy dilemma. Unlike Ackerman, I suggest a series of mechanisms designed to allow for the actual participation of ordinary citizens in the constitution and re-constitution of government

    De-Constitutionalizing Democracy

    Get PDF

    De-Constitutionalizing Democracy

    Get PDF

    Trajectory-dependent energy loss for swift He atoms axially scattered off a silver surface

    Get PDF
    Angle- and energy-loss- resolved distributions of helium atoms grazingly scattered from a Ag(110) surface along low indexed crystallographic directions are investigated considering impact energies in the few keV range. Final projectile distributions are evaluated within a semi-classical formalism that includes dissipative effects due to electron-hole excitations through a friction force. For mono-energetic beams impinging along the [11ˉ0][1\bar{1}0], [11ˉ2][1\bar{1}2] and [11ˉ0][1\bar{1}0] directions, the model predicts the presence of multiple peak structures in energy-loss spectra. Such structures provide detailed information about the trajectory-dependent energy loss. However, when the experimental dispersion of the incident beam is taken into account, these energy-loss peaks are completely washed out, giving rise to a smooth energy-loss distribution, in fairly good agreement with available experimental data

    Juncus emmanuelis

    Get PDF
    This species is endemic to a small area in the southwestern Iberian Peninsula, with subpopulations scattered in approximately 16 localities. It is assessed as Endangered (EN B2ab(ii,iii,iv)) because it has an Area of Occupancy (AOO) of less than 500 km2 and shows signs of severe fragmentation due to the ongoing transformation of its specific habitat of sandy soils with an impermeable underlayer in temporary pools, as a result of several ongoing major threats associated with intensive agricultural activities. Based on this information, a continuing decline in the AOO, habitat quality and number of subpopulations has been inferred. Additional research and conservation action is needed for this species

    Experimental evaluation of the injection force exerted in intraocular lens delivery with syringe-type injectors

    Get PDF
    The process of intraocular lens (IOL) delivery within the capsular bag during cataract surgery is crucial, as the integrity of the IOL, the injector and the ocular structures should be preserved at all times. This study aims to obtain the main parameters that affect the injection force exerted in the ejection of an intraocular lens (IOL) through syringe-type injectors. For that purpose, ejection tests were carried out in vitro, measuring the resistance force throughout the entire delivery process. The effect of IOL material, haptic design, IOL thickest area and ophthalmic viscosurgical device (OVD) was studied by ejecting seven IOLs with four syringe-type injectors of different sizes, 3.0, 2.2 and 1.8 mm. In all injectors, plate hydrophilic IOLs present the lowest resistance forces; hydrated C-loop hydrophobic IOLs present higher forces and the C-loop hydrophobic IOL in dry conditions presents the highest resistance forces. All IOLs could be properly delivered with an injector size of 2.2 mm, making injector sizes of 3.0 mm outdated. The injector size of 1.8 mm damaged several IOLs. IOL material and cartridge nozzle size were the most influential parameters in IOL delivery. IOL thickest area was also relevant but in a lesser extent whereas IOL haptic design was not as relevant

    What\u27s Democracy Got to Do With It?: A Critique of Liberal Constitutionalism

    Get PDF
    This paper examines the extent to which Ronald Dworkin\u27s liberal constitutionalism, as presented in his recent work Is Democracy Possible Here? Principles for a New Political Debate, can provide the basis and impetus for the realization of democracy in contemporary societies. The paper is divided into three main sections. We begin by locating the broader institutional contexts within which debates about the importance and salience of democratic politics have taken place and introducing Dworkin\u27s distinctive and defiant contribution to those debates. In the second and main section, we offer a substantial critique of Dworkin\u27s proposals and demonstrate how his (and fellow constitutionalists\u27) liberal project may be as much a part of the problem as the solution. That critique is divided into four parts, it includes a series of philosophical, political, constitutional, and historical arguments against the democratic credentials of Dworkin\u27s project. The third section explores a different approach to how democracy can be more effectively and fully mobilized to meet present-day challenges, the emphasis here is on more affirmative and constructive proposals. By way of conclusion, we speculate on the directions that further efforts might take to fulfill the promise of democratic politics in contemporary societies. We maintain that, if democracy is to be realizable, then it needs to be of a more robust and less derivative kind than Dworkin\u27s liberal project envisages. Rather than arguing that any remnants of constitutionalism should be abandoned, we propose to re-dress as we challenge the supposed balance between constitutionalism and democracy and, in its place, combine a strong democracy with a weak constitutionalism

    Democracy and Revolution: An Enduring Relationship?

    Get PDF
    We take the view that, as understood from a thoroughly democratic standpoint, revolutions need not be “uncontainable and disorderly occurrences that resist confinement”. Instead, we insist that it is better and feasible to think of certain revolutions as being part and parcel of a vigorous democratic culture and sensibility. Indeed, we contend that a democratic revolution can not only occur “when challengers self-consciously adopt non-constitutional means to transform the state with the consent of their fellow citizens”, but also when challengers self-consciously adopt and use constitutional means to transform the state. For us, there is no sharp or enduring distinction between some revolutions and constitutional changes: a robust democracy will incorporate constitutional means by which to facilitate periodic revolutions. In this sense, we follow through on Albert’s claim that “there can be no higher authorizing force than citizens themselves” and take even more seriously than he does “the promise of revolution as the most noble civic ambition”. To paraphrase de Tocqueville, there is no need in a true democracy to invent the end of revolution as it becomes a continuing and integral part of democratic arrangements themselves. The paper is divided into three parts. The first part is devoted to explaining how democratic revolutions can be profitably understood as exercises of constituent power unmediated by any particular way of proceeding, reference will be made to contemporary developments in global politics. The second part contends that the democratic legitimacy of a revolution does not depend only on whether it was supported by citizens or on whether the regime it creates governs in the name of the citizenry, but also on whether it attempts re-produce its democratic impulse through a ‘weak’ constitutional order that contains participatory procedures for its own transformation. Finally, in the third part, we defend the radical proposal that an unconditional commitment to democracy implies that revolutionary-initiated constitutions should leave the door open for future exercises of constituent power or, what is the same thing, for future democratic revolutions. Throughout, we develop and stand by an account of democracy as both a theory and practice that re-orders the traditional relationship between constitutionalism and democracy
    corecore