Weak-Field Gravity of Circular Cosmic Strings

A weak-field solution of Einstein's equations is constructed. It is generated by a circular cosmic string externally supported against collapse. The solution exhibits a conical singularity, and the corresponding deficit angle is the same as for a straight string of the same linear energy density. This confirms the deficit-angle assumption made in the Frolov-Israel-Unruh derivation of the metric describing a string loop at a moment of time symmetry.Comment: 15 page

Prejuicios que silencian: Injusticia Testimonial y Muerte Hermenéutica

En el presente texto se retoma la noción de injusticia epistémica desarrollada por Miranda Fricker, así como algunos avances posteriores que dicho concepto posibilitó, para mostrar las facetas epistémicas que acompañan a diversas formas de exclusión y marginación, en las cuales las desigualdades de género juegan un papel importante. Se sostiene que el feminismo contemporáneo puede caracterizarse, al menos en parte, por un afán de subsanar este tipo de injusticias. Empero, como también se evidencia en este texto, subsisten todavía en su interior contradicciones y prejuicios que conducen al mantenimiento de la condición de muerte hermenéutica en la que se encuentran las poblaciones trans y las personas dedicadas al trabajo sexual. De manera general, este trabajo busca revelar la existencia de un conjunto de puntos ciegos o prejuicios que aún perviven en el feminismo contemporáneo y que incluso han ido tomando fuerza; me refiero concretamente a las posiciones transexcluyentes y abolicionistas del trabajo sexual que en la actualidad promueven narrativas en torno a estos dos sectores y que potencian su marginalidad y exclusión

A Transformative Approach to Anti- Discrimination Law in Latin America

In Latin America, a region with particular problems and challenges, anti-discrimination legal provisions have been rapidly growing, although without much scholarly attention. Recent reforms can be framed as mere improvements of the right to equality, as guarantees required to smooth market interactions or, alternatively, as cynical progress that prevent more radical understandings. Against these approaches, this thesis provides an account of the emancipatory potential of anti-discrimination law (ADL) in Latin America and its place within progressive political projects. Rather than providing a doctrinal reconstruction, a complete theoretical account, or a detailed legal framework of this field of law, this research builds on contemporary constitutional debates and critical social theories to see how the practice of ADL in Latin America provides ‘spaces of anticipatory illumination’ of what a transformative account of ADL would look like. For this purpose, I develop two main argumentative lines, which structures this work in two parts. According to the first, we need a constitutional conception of ADL that can make sense of the recent constitutional (trans)formations in the region, committed at tackling discrimination. Taking into account the raw materials we have at hand, the vast repertoire of anti-discrimination provisions enacted in the last decades, it develops a constitutional conception of ADL that can create the conditions for an effective enforcement of the generous anti-discrimination commitments. The second argumentative line rests on the need to advance a critical social theory of ADL in Latin America. Without it, the first argumentative line is doomed to fail. In concrete terms, this second line rests on the need to critically understand the phenomenon under study, in this case, discrimination in Latin America, and the role of law in addressing it. By looking at the recent practice of ADL in Latin America through the lens of a critical social theory, we can understand the strengths and limits, the opportunities and dangers that derive from this emergent field of law. Drawing mainly on the work of Nancy Fraser, I argue that ADL in Latin America could be an example of ‘nonreformist reform’, which ‘changes more than the specific institutional features they explicitly target’, and ‘alter the terrain upon which later struggles will be waged.’ A ‘normative reconstruction’ of recent reforms and practice in ADL allows us to develop six principles that set the case for a transformative approach suitable for the challenges the region is currently facing: state intervention, group dimension, challenging stance, socio-economic lens, political axis, legal empowerment/mobilization. In particular, this research starts from existing antidiscrimination provisions in the region, and seeks a roadmap of further legal reforms within a transformative approach

LA DIMENSIÓN CONSTITUCIONAL DE LAS INSTITUCIONES NACIONALES DE DERECHOS HUMANOS

Este trabajo aborda la dimensión constitucional de las instituciones nacionales de derechos humanos. En el marco del actual proceso constituyente chileno, el artículo analiza las principales preguntas constitucionales que pueden surgir respecto a la institucionalidad de derechos humanos en Chile, con especial énfasis en la posición y el rol que debiera jugar el actual Instituto Nacional de Derechos Humanos en el futuro orden constitucional. Para ello, y después de analizar la pregunta sobre una eventual autonomía constitucional para una institución nacional de derechos humanos, el artículo reflexiona sobre las principales opciones o posibilidades regulatorias: modelo unipersonal o colegiado; concentración o fragmentación de instituciones; y discusiones generales sobre sus atribuciones.

Embedding of the Brane into Six Dimensions

Embedding of the brane metric into Euclidean (2+4)-space is found. Brane geometry can be visualized as the surface of the hyper-sphere in six dimensions which 'radius' is governed by the cosmological constant. Minkowski space in this picture is lied on the intersection of this surface with the plane formed by the extra space-like and time-like coordinates.Comment: 3 pages, LaTeX, no figures, one citation was eddie

Effect of dietary protein intake on calf resilience to Haemonchus placei infection

Twenty, 2-3-month-old worm free male Holstein calves, were assigned to two groups each containing ten animals. Each group was offered one of two diets: High (HP) and Low (LP) protein with 257 and 91 gkg-1 dry matter respectively, balanced for energy and minerals. After an initial period of 4 weeks on the diets, the calves from each group were subdivided into two groups of four and six calves. A trickle infection of 5,000 Haemonchus placei L3 was given twice a week for nine weeks to the sub group of six calves (I). The remaining four calves from each dietary group were used as non-infected control (C). Four weeks after the last infection, all calves were slaughtered and worm burdens counts. Carried out Biochemical determinations, faecal egg counts and body weights were carried out once a week. The HP group had significantly higher mean adult worm burdens (11,900 ± 7,660) when compared with BP (5,450 ± 7,895). Faecal egg counts were higher in the HP than LP group. Despite higher worm burdens, resilience was increased in the HP calves, with higher packed cell volume values as well as body weight when compared with the LP group.Vinte bezerros com 2 a 3 meses de idade criados livres de vermes foram divididos em 2 grupos com 10 animais cada alimentados com alta proteína (HP) e baixa proteina (LP) com 257 e 91 g kg-1 de proteína na materia seca respectivamente, devidamente balanceado em energia e minerais. Após 4 semanas submetidos a estas duas dietas cada grupo original foi subdividido em 2 grupos, um contendo 4 animais não infectado (C) e 6 animais infectados (I). O grupo infectado recebeu 5.000 larvas de Haemonchus placei duas vezes por semana por um período de 9 semamas, após 4 semanas da última infecção todos os animais foram sacrificados e realizada a contagem de vermes. Semanalmente foram feitas as pesagens dos animais, número de ovos por grama de fezes e colheita de sangue para determinação do hematócrito, hemoglobina, albumina e proteína total. A contagem de ovos por grama de fezes foi superior no grupo de HP em relação ao grupo de LP, tendo em vista que o número de vermes adultos no grupo HP (11.900 ± 7.660) foi maior que o grupo de LP (5.450 ± 7.895) . Apesar do número superior de vermes encontrado no grupo HP, observou-se valores superiores de hematócrito e peso vivo quando comparado com o grupo de LP (p<0,05), demonstrado que a suplementação protéica possibilita uma melhor resilience em bezerros infectados com Haemonchus placei

Effect of dietary protein intake on calf resilience to Haemonchus placei infection

Twenty, 2-3-month-old worm free male Holstein calves, were assigned to two groups each containing ten animals. Each group was offered one of two diets: High (HP) and Low (LP) protein with 257 and 91 gkg-1 dry matter respectively, balanced for energy and minerals. After an initial period of 4 weeks on the diets, the calves from each group were subdivided into two groups of four and six calves. A trickle infection of 5,000 Haemonchus placei L3 was given twice a week for nine weeks to the sub group of six calves (I). The remaining four calves from each dietary group were used as non-infected control (C). Four weeks after the last infection, all calves were slaughtered and worm burdens counts. Carried out Biochemical determinations, faecal egg counts and body weights were carried out once a week. The HP group had significantly higher mean adult worm burdens (11,900 ± 7,660) when compared with BP (5,450 ± 7,895). Faecal egg counts were higher in the HP than LP group. Despite higher worm burdens, resilience was increased in the HP calves, with higher packed cell volume values as well as body weight when compared with the LP group.Vinte bezerros com 2 a 3 meses de idade criados livres de vermes foram divididos em 2 grupos com 10 animais cada alimentados com alta proteína (HP) e baixa proteina (LP) com 257 e 91 g kg-1 de proteína na materia seca respectivamente, devidamente balanceado em energia e minerais. Após 4 semanas submetidos a estas duas dietas cada grupo original foi subdividido em 2 grupos, um contendo 4 animais não infectado (C) e 6 animais infectados (I). O grupo infectado recebeu 5.000 larvas de Haemonchus placei duas vezes por semana por um período de 9 semamas, após 4 semanas da última infecção todos os animais foram sacrificados e realizada a contagem de vermes. Semanalmente foram feitas as pesagens dos animais, número de ovos por grama de fezes e colheita de sangue para determinação do hematócrito, hemoglobina, albumina e proteína total. A contagem de ovos por grama de fezes foi superior no grupo de HP em relação ao grupo de LP, tendo em vista que o número de vermes adultos no grupo HP (11.900 ± 7.660) foi maior que o grupo de LP (5.450 ± 7.895) . Apesar do número superior de vermes encontrado no grupo HP, observou-se valores superiores de hematócrito e peso vivo quando comparado com o grupo de LP (p<0,05), demonstrado que a suplementação protéica possibilita uma melhor resilience em bezerros infectados com Haemonchus placei

Towards the Identification of an In Vitro Tool for Assessing the Biological Behavior of Aerosol Supplied Nanomaterials

Nanoparticles (NP)-based inhalation systems for drug delivery can be administered in liquid form, by nebulization or using pressurized metered dose inhalers, and in solid form by means of dry powder inhalers. However, NP delivery to the lungs has many challenges including the formulation instability due to particle-particle interactions and subsequent aggregation, causing poor deposition in the small distal airways and subsequent alveolar macrophages activity, which could lead to inflammation. This work aims at providing an in vitro experimental design for investigating the correlation between the physico-chemical properties of NP, and their biological behavior, when they are used as NP-based inhalation treatments, comparing two different exposure systems. By means of an aerosol drug delivery nebulizer, human lung cells cultured at air-liquid interface (ALI) were exposed to two titanium dioxide NP (NM-100 and NM-101), obtained from the JRC repository. In parallel, ALI cultures were exposed to NP suspension by direct inoculation, i.e., by adding the NP suspensions on the apical side of the cell cultures with a pipette. The formulation stability of NP, measured as hydrodynamic size distributions, the cell viability, cell monolayer integrity, cell morphology and pro-inflammatory cytokines secretion were investigated. Our results demonstrated that the formulation stability of NM-100 and NM-101 was strongly dependent on the aggregation phenomena that occur in the conditions adopted for the biological experiments. Interestingly, comparable biological data between the two exposure methods used were observed, suggesting that the conventional exposure coupled to ALI culturing conditions offers a relevant in vitro tool for assessing the correlation between the physico-chemical properties of NP and their biological behavior, when NP are used as drug delivery systems