Buenos Aires: the neoliberal orientation of metropolitan development

Este artículo analiza las transformaciones de la ciudad metropolitana de Buenos Aires con la aplicación de políticas de orientación neoliberal que modificaron las relaciones entre mercado, sociedad y Estado. Buenos Aires ha sido históricamente producida y consumida con predominio de modalidades mercantiles, una relativa prescindencia del Estado, particularmente en lo que hace a suelo y vivienda, y el esfuerzo de los sectores de ingresos medios y bajos. La reestructuración neoliberal, iniciada en 1976, amplió y fortaleció ese predominio: se mercantilizaron procesos no mercantiles, re-mercantilizaron algunos desmercantilizados y la configuración metropolitana se subordinó a orientaciones privadas. Correlativamente, crecieron los procesos no mercantiles populares, de autoproducción e irregularidad, para la producción-consumo de suelo, vivienda y servicios.This article analyzes the transformations of the metropolitan city of Buenos Aires since the implementation of policies characterized by neoliberal orientation, which changed relations between market, society and the State. Buenos Aires has historically been produced and consumed with predominance of commercial arrangements, a relative disregard by the State, particularly concerning land and housing, and the effort of middle and low income sectors. The neoliberal restructuring, begun in 1976, expanded and strengthened this predominance: uncommodified processes have been commodified, some previously decommodified have been recommodified and the metropolitan configuration became subordinated to private directions. Correspondingly, popular nonmarket processes of self-production and irregularity have developed, for production-consumption of land, housing and services.Fil: Pirez, Pedro Tomas. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Octyl co-grafted PrSO3H/SBA-15:tunable hydrophobic solid acid catalysts for acetic acid esterification

Propylsulfonic acid (PrSO3H) derivatised solid acid catalysts have been prepared by post modification of mesoporous SBA-15 silica with mercaptopropyltrimethoxysilane (MPTMS), with the impact of co-derivatisation with octyltrimethoxysilane (OTMS) groups to impart hydrophobicity to the catalyst investigated. Turn over frequencies (TOF) for acetic acid esterification with methanol increase with PrSO3H surface coverage across both families suggesting a cooperative effect of adjacent acid sites at high acid site densities. Esterification activity is further promoted upon co-functionalisation with hydrophobic octyl chains, with inverse gas chromatography (iGC) measurements indicating increased activity correlates with decreased surface polarity or increased hydrophobicity

Clamped accelerating structures for the generation of high brightness electron beams.

This dissertation will illustrate the design, theory and fabrication of a newgeneration of radiofrequency (RF) photoinjector aimed at obtaining signicantimprovements in beam brightness, through an innovative accelerating cavity design,with minimized RF breakdown rates and a novel fabrication technique. TheUCLA 1.4 cell RF photoinjector has been inspired by the SPARC (LNF-INFN,Italy) 1.6 cell RF electron gun currently operating in the Pegasus beamline. Usingthe clamping technique with the INFN proprietary-design gaskets, the fabricationfor the 1.4 cell photoinjector the INFN can be completed without any brazingprocess. Careful rounding of all the inside surfaces allows better management ofthe pulsed heating temperature rise that largely contributes to the rf breakdownlimits of older generations of high gradient electron guns. Finally, the clampingtechnique and innovative gasket design offers a lower risk assembly and lowerfabrication costs.The UCLA 1.4 cell rf electron gun has been designed to operate at a 120MV/mgradient and an optimal injection phase of 70 degrees in order to increase the extractionfield experienced by the electrons at photo-emission by a factor of 1.9 comparedto the one in the standard 1.6 cell design running at the same peak eld. Themaximum achievable beam brightness in a RF photogun depends on the extractioneld with a scaling which diers for the various regimes of operation (cigar,pancake, blowout). Nevertheless, for all cases, improving the extraction fieldimproves the beam brightness at least linearly regardless of operating regime.From the electromagnetic point of view the gun presents a large mode separation,an extra pumping port for dipole moment compensation, a racetrack fullcell geometry for quadrupole moment compensation, strongly rounded ellipticaliris and coupler for minimal pulsed heating. The electron gun has also been designedto be compatible with several cutting edge experiments. The inclusion ofoblique incidence laser ports allows for short focal length laser illumination onthe cathode to generate ultra-low emittance bunches as demonstrated in recentexperiments. The new photoinjector is also compatible with a load-lock chamberto test advanced photocathodes, such as alkali antimonide cathodes. Thesepromising materials have yet to be tested in high gradient accelerating cavitiesdue to the lack of an ultra-high vacuum (UHV) storage system that is capable ofloading cathodes into the injector without breaking vacuum.The clamping technique has proven useful in the assembly of accelerating cavities.In the last chapter of this thesis, we will also discuss the design and use of theclamping method in the realization of an X-band deflecting cavity that will playa role in the future ultrafast electron diffraction (UED) experiments at UCLA.The goal of the new deflecting cavity is to develop an innovative, inexpensive andlow energy UED system that provides short bunches and others improvements inthe temporal resolution of ultrafast electron diffraction measurements

New technology based on clamping for high gradient radio frequency photogun

High gradient rf photoguns have been a key development to enable several applications of high quality electron beams. They allow the generation of beams with very high peak current and low transverse emittance, satisfying the tight demands for free-electron lasers, energy recovery linacs, Compton/Thomson sources and high-energy linear colliders. In the present paper we present the design of a new rf photogun recently developed in the framework of the SPARC_LAB photoinjector activities at the laboratories of the National Institute of Nuclear Physics in Frascati (LNF-INFN, Italy). This design implements several new features from the electromagnetic point of view and, more important, a novel technology for its realization that does not involve any brazing process. From the electromagnetic point of view the gun presents high mode separation, low peak surface electric field at the iris and minimized pulsed heating on the coupler. For the realization, we have implemented a novel fabrication design that, avoiding brazing, strongly reduces the cost, the realization time and the risk of failure. Details on the electromagnetic design, low power rf measurements and high power radiofrequency and beam tests performed at the University of California in Los Angeles (UCLA) are discussed in the paper

The reproductive success of bovine sperm after sex‑sorting: a meta‑analysis

In the three decades since its inception, the sex-sorting technology has progressed significantly. However, field studies report conflicting findings regarding reproductive outcomes. Therefore, we conducted this meta-analysis of all trials published between 1999 and 2021. Non-return rates after 24 or 60 d (NRR 24/60), pregnancy, calving, abortion, and stillbirth rates were compared after AI with sex-sorted vs non-sorted sperm. Additionally, the impact of recent developments in the sex-sorting technology was assessed. Of 860 studies found, 45 studies (72 trials) provided extractable data and were included. Overall, the results of this meta-analysis provided evidence that the NRR 24/60 was diminished by 13%, pregnancy rates were reduced by 23% (25% cows, 21% heifers) and calving rates were reduced by 24% when using sex-sorted sperm. Enhancing the dosage to 4 million sex-sorted sperm/straw (including recent improvements, high vs low dose) as well as using fresh sex-sorted sperm (sorted vs non-sorted) increased pregnancy rate ratios by 7 percentage points. The refinement of the sex-sorting technology after 2015 resulted in a lowered reduction of pregnancy and calving rate of 19% and 23%, respectively. Whereas abortion rates were similar, the stillbirth of male calves was increased by 6.3%

El derecho a la ciudad y la mercantilización de la urbanización

La producción mercantil de la ciudad excluye a muchos del goce de la vida urbana. La autoproducción de viviendas aparece como un efecto –insuficiente– de la escasez de alternativas propuestas desde el Estado.Fil: Pirez, Pedro Tomas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Estudios de América Latina y el Caribe; Argentina. Universidad Torcuato Di Tella; Argentina. Universidad Nacional de Tres de Febrero; Argentina. Universidad Nacional de Córdoba; Argentina. Universidad Nacional de Rosario; Argentin

The Heterogeneous Production and Consumption formsof Latin American Urbanization

Este artículo se propone consolidar algunos intentos previos orientados a entender la urbanización en las sociedades latinoamericanas, tanto en relación con algunas cuestiones particulares, especialmente infraestructuras y servicios, como con la urbanización como totalidad. Para ello se considera a la urbanización como un proceso por medio del cual la población ocupa un espacio que ha sido transformado para soportar su asentamiento aglomerado. Esto es, habilitación, o adecuación, de una porción de la superficie de la tierra como suelo urbano: segmento espacial que puede sostener las construcciones (lotes, viviendas, infraestructuras y equipamientos, locales para actividades, etcétera) que puede soportar la reproducción de la vida social, al sostener al conjunto de las relaciones que estructuran y/o desestructuran a cada sociedad en particular. Tal adecuación es el resultado de procesos productivos particulares cuyos productos son los componentes de la urbanización. Es por ello que esta última depende del predominio, en cada lugar y momento, de ciertas modalidades particulares de producción. Consecuentemente, estudiar la urbanización en América Latina es identificar cómo se produce-consume ese conjunto de bienes en sociedades capitalistas dependientes, en los diferentes momentos en los que esos procesos se desenvuelven. Para ese estudio el artículo se propone analizar algunos aspectos relevantes: la urbanización en el capitalismo en general y en las sociedades avanzadas, la urbanización en el capitalismo dependiente de la sociedades latinoamericanas y, en estos casos, la fuerte heterogeneidad de modalidades de producción - consumo (mercantiles, mercantil simples, no mercantiles, desmercantilizadas) que se combinan y articulan.This article aims to consolidate some previous attempts to understand the urbanization in Latin American societies, both in relation to some particular issues, especially infrastructure and services, and to urbanization as a whole. To do so the urbanization is considered as a process by which the population occupies a space that has been transformed to support its agglomerate settlement. This is, fitness of a portion of the surface of the Earth as urban land: space segment that can sustain constructions (lots, housing, infrastructure and equipment, premises for activities, etc.) to support social life, to hold the set of relations that structure and / or de structured each particular society. Such adaptation is the result of specific production processes whose products are components of urbanization. That is why the latter depends on the prevalence, in every place and time, of certain particular methods of production. Such adaptation is the result of specific production processes whose products are components of urbanization. That is why the latter depends on the prevalence, in every place and time, of certain particular methods of production. Consequently, the study of the Latin American urbanization needs to identify how it is produced and consumed that set of goods in dependent capitalist societies, at different moments in which these processes unfold. For this, the article analyzes some relevant aspects: urbanization under capitalism in general and in advanced societies, urbanization in dependent capitalism in Latin American societies and, in these cases, the strong heterogeneity of patterns of production - consumption (commodified, simple commodity production, noncommodified and de-commodified) that are combined and articulated.Fil: Pirez, Pedro Tomas. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Estudios de América Latina y el Caribe; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Bovine sperm-oviduct interactions are characterized by specific sperm behaviour, ultrastructure and tubal reactions which are impacted by sex sorting

To date sperm-oviduct interactions have largely been investigated under in vitro conditions. Therefore we set out to characterize the behaviour of bovine spermatozoa within the sperm reservoir under near in vivo conditions and in real-time using a novel live cell imaging technology and a newly established fluorescent sperm binding assay. Sperm structure and tubal reactions after sperm binding were analysed using scanning and transmission electron microscopy and histochemistry. As a model to specify the impact of stress on sperm-oviduct interactions, frozen-thawed conventional and sex-sorted spermatozoa from the same bulls (n = 7) were co-incubated with oviducts obtained from cows immediately after slaughter. Our studies revealed that within the oviductal sperm reservoir agile (bound at a tangential angle of about 30°, actively beating undulating tail), lagging (bound at a lower angle, reduced tail movement), immotile (absence of tail movement) and hyperactivated (whip-like movement of tail) spermatozoa occur, the prevalence of which changes in a time-dependent pattern. After formation of the sperm reservoir, tubal ciliary beat frequency is significantly increased (p = 0.022) and the epithelial cells show increased activity of endoplasmic reticula. After sex sorting, spermatozoa occasionally display abnormal movement patterns characterized by a 360° rotating head and tail. Sperm binding in the oviduct is significantly reduced (p = 0.008) following sexing. Sex-sorted spermatozoa reveal deformations in the head, sharp bends in the tail and a significantly increased prevalence of damaged mitochondria (p < 0.001). Our results imply that the oviductal cells specifically react to the binding of spermatozoa, maintaining sperm survival within the tubal reservoir. The sex-sorting process, which is associated with mechanical, chemical and time stress, impacts sperm binding to the oviduct and mitochondrial integrity affecting sperm motility and function

Metropolitan government as governance: between self-regulation and political orientation

Este artículo presenta una perspectiva para estudiar al gobierno urbano local. Analiza la argumentación de la gobernabilidad-governance, entendida como la propuesta de un método o instrumento de gobierno que limita la capacidad de percibir el papel del Estado y las situaciones de concentración de poder. Propone introducir la noción de orientación de los procesos sociales y terri- toriales desde los aparatos político-burocráticos; se refiere al Área Metropolitana de Buenos Aires, identificando una estructura interjurisdiccional caracterizada por el predominio del gobierno federal, estudiando los procesos que hicieron parte de la reestructuración neoliberal durante los años noventaThis paper presents an approach to study the local urban government. It reviews the arguments of governability-governance, like a proposal of a method or instrument of government, which limits the ability to perceive the role of the State and the situations of concentration of power. It proposes to introduce the notion of orientation of social and territorial processes from the political-bureaucratic apparatuses. It refers to the Metropolitan Area of Buenos Aires, identifying an inter-jurisdictional structure characterized by the dominance of the federal government, studying the processes and policies that were part of the neoliberal restructuring over the 1990’s.Fil: Pirez, Pedro Tomas. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Hermanos acogedores

Este trabajo de fin de grado está centrado en la figura que realizan los hermanos acogedores a la hora de tener a un menor de acogida en su hogar. Eltrabajo está basado en una entrevista mediante la cual, conocemos la forma en la que los hermanos ven la situación, como la asimilan, la hora de lallegada del menor, la despedida y todo lo que esto conlleva. Para finalizar nos encontramos con una serie de propuestas de mejora, y las conclusiones alas que he llegado tras la realización de este trabajo.Grado en Trabajo Socia