Langevin Dynamics of a Polymer with Internal Distance Constraints

We present a novel and rigorous approach to the Langevin dynamics of ideal polymer chains subject to internal distance constraints. The permanent constraints are modelled by harmonic potentials in the limit when the strength of the potential approaches infinity (hard crosslinks). The crosslinks are assumed to exist between arbitrary pairs of monomers. Formally exact expressions for the resolvent and spectral density matrix of the system are derived. To illustrate the method we study the diffusional behavior of monomers in the vicinity of a single crosslink within the framework of the Rouse model. The same problem has been studied previously by Warner (J. Phys. C: Solid State Phys. {\bf 14}, 4985, (1981)) on the basis of Lagrangian multipliers. Here we derive the full, hence exact, solution to the problem.Comment: To appear in PRE, Figures on reques

Size and scaling in ideal polymer networks

The scattering function and radius of gyration of an ideal polymer network are calculated depending on the strength of the bonds that form the crosslinks. Our calculations are based on an {\it exact} theorem for the characteristic function of a polydisperse phantom network that allows for treating the crosslinks between pairs of randomly selected monomers as quenched variables without resorting to replica methods. From this new approach it is found that the scattering function of an ideal network obeys a master curve which depends on one single parameter $x= (ak)^2 N/M$, where $ak$ is the product of the persistence length times the scattering wavevector, $N$ the total number of monomers and $M$ the crosslinks in the system. By varying the crosslinking potential from infinity (hard $\delta$-constraints) to zero (free chain), we have also studied the crossover of the radius of gyration from the collapsed regime where R_{\mbox{\tiny g}}\simeq {\cal O}(1) to the extended regime R_{\mbox{\tiny g}}\simeq {\cal O}(\sqrt{N}). In the crossover regime the network size R_{\mbox{\tiny g}} is found to be proportional to $(N/M)^{1/4}$.Comment: latex, figures available on request, to be published: J. Phys I Franc

Citizen Outsiders: How the Struggles of Romanian Roma in London Challenge the Conception of Citizenship

Conventionally citizenship has been understood as membership in nation states requiring certain rights and providing certain entitlements. Over the last twenty years, critical perspectives asserted that citizenship is not merely membership, let alone membership of a state. It is now argued that historically and theoretically citizenship involves a distinction between an outside and inside and often its boundaries become the sites of social struggle. Critical perspectives on citizenship invite us to think of citizenship as processes by which political subjectivity, understood as the right to make claims to rights, can be recognised and enacted. As these perspectives allow us to think critically about citizenship beyond membership and the nation state, in this thesis I focus first on the mechanism related to the logic of citizenship that dismisses political agency of those who do not count as political subjects and makes them into what I refer to as ‘citizen outsiders’. Second, I draw on critical perspectives on citizenship and ethnographic methods to examine how Romanian Roma in an East London borough, who are discursively constituted as lacking capacities to act as citizens, contest the ways they are problematised. By focusing on their everyday life struggles as acts of citizenship, I argue that Roma in London do make claims to rights and, in doing so, enact themselves as citizens. Finally I draw conclusions about the ways Roma are problematised and how Roma disrupt these positioning with various acts of citizenship

La conciliación extrajudicial en temas de familia (Ley Nº 29876 que modifica la ley Nº 26872 y el D.L. 1070)

En el presente trabajo se pretende establecer la relación existente entre los derechos disponibles en materia de familia y la vulneración de los derechos de terceros, en este caso, menores de edad, quienes son los que a través de sus padres son representados al no tener capacidad jurídica. Sin embargo, podría darse el caso de vulnerar sus derechos e interés del menor al disponer de sus derechos. Es necesario regular normativamente estas posibilidades y definir la libre disposición de derechos que es la pieza fundamental de los sistemas alternativos

Los efectos de la homologación de la transacción extrajudicial Análisis Casatorio: casación nº 3435-2009-arequipa

La transacción es un medio de solución de conflictos, mediante el cual las partes autocomponen sus diferencias, a través de concesiones recíprocas, con ahorro de tiempo y gastos, aliviando la carga procesal. Pese a ello y a la notoria relevancia social y jurídica que dicha institución posee, se advierte que no se ha comprendido su verdadero contenido. Razón por la cual, a continuación se realizará un breve análisis acerca de las implicancias jurídicas que posee en nuestro ordenamiento. Posteriormente, se comparará la transacción extrajudicial y judicial, junto con la homologación y los efectos como cosa juzgada. Por último, se realizará un análisis sobre la Casación Nº 3435-2009-Arequipa

A Response to Telford Taylor\u27s Nuremberg and Vietnam: An American Tragedy

Professor Telford Taylor, who is best remembered as Justice Robert H. Jackson\u27s successor as Chief of Counsel at Nuremberg after the War Crimes trial of the major war criminals, became an instant giant of the new industry by suggesting that if one were to apply to Dean Rusk, Robert McNamara, McGeorge Bundy, Walt Rostow and General William Westmoreland the same standards that were applied in the trial of General Tomoyuki Yamashita there would be a very strong possibility that they would come to the same end as he did. \u27 This suggestion by the person described on the dust jacket as U.S. Chief Counsel at Nuremberg inevitably elevates Professor Taylor to the status of a first magnitude star among the scapegoat makers. Regretably, Professor Taylor produced a work replete with demonstrable errors of law and contradictions. He thereby forfeits the opportunity to assume a place among the very few who are qualified by experience and academic standing to produce trustworthy evidence of what international law really is. There are, of course, too many who, without experience in the field, write at length about what it ought to be and some who affirm that it is what it is not

A Response to Douglas J. Feith\u27s Law In The Service of Terror - The Strange Case of the Additional Protocol

In the article mentioned in the title, Douglas J. Feith, Deputy Assistant Secretary of Defense for International Negotiation, characterizes the 1977 Protocol I Additional to the 1949 Geneva Conventions as a pro-terrorist treaty masquerading as humanitarian law

Incluindo Cidadãos(ãs) que não 'Se Encaixam'

This article analyzes inclusive dimensions of the liberal antidiscrimination tradition that is grounded in the reinforcement of civil and political liberties and in neutral public institutions, where each member of society is relevant as a rights- and duty-bearer under the umbrella of the rule of law. Drawing on our experience with the inclusion of Romani people, the largest ethnic minority group in Europe, we examine the challenges of the liberal inclusion discourse when finding its realization in hierarchically stratified European societies. Circumscribed by laissez-faire markets and politics, they let vast socio-economic inequalities and cultural stereotypes prevail practically untouched. We argue that the contradiction between these citizenship-based and market-based liberal institutions gradually corrupt the process of equalizing right-holders and results in Roma to be pushed even further to the margins of society. The inclusion policies recognize this contradiction of formal equality as they are made for those who fail ‘to fit in’ and those who do not ‘count’ yet. We point out that many Roma do not effectively experience the promise of citizenship since Roma inclusion policies do not fully grant them the status of those who have the right to have rights. &nbsp