Investigación sobre las causas que pudieron originar el hundimiento de la cubierta del tercer depósito del Canal de Isabel II en 1905

En la presente investigación se analiza la causa del hundimiento del cuarto compartimento del Tercer Depósito del Canal de Isabel II el 8 de abril de 1905, uno de los más graves de la historia de la construcción en España: fallecieron 30 personas y quedaron heridas otras 60. El Proyecto y Construcción de esta estructura era de D. José Eugenio Ribera, una de las grandes figuras de la ingeniería civil en nuestro país, cuya carrera pudo haber quedado truncada como consecuencia del siniestro. Dado el tiempo transcurrido desde la ocurrencia de este accidente, la investigación ha partido de la recopilación de la información relativa al Proyecto y a la propia construcción de la estructura, para revisar a continuación la información disponible sobre el hundimiento. De la construcción de la cubierta es interesante destacar la atrevida configuración estructural, cubriéndose una inmensa superficie de 74.000 m2 mediante una sucesión de bóvedas de hormigón armado de tan sólo 5 cm de espesor y un rebajamiento de 1/10 para salvar una luz de 6 m, que apoyaban en pórticos del mismo material, con pilares también muy esbeltos: 0,25 m de lado para 8 m de altura. Y todo ello en una época en la que la tecnología y conocimiento de las estructuras con este "nuevo" material se basaban en buena medida en el desarrollo de patentes. En cuanto a la información sobre el hundimiento, llama la atención en primer lugar la relevancia de los técnicos, peritos y letrados que intervinieron en el juicio y en el procedimiento administrativo posterior, poniéndose de manifiesto la trascendencia que el accidente tuvo en su momento y que, sin embargo, no ha trascendido hasta nuestros días. Ejemplo de ello es el papel de Echegaray -primera figura intelectual de la época- como perito en la defensa de Ribera, de D. Melquiades Álvarez -futuro presidente del Congreso- como abogado defensor, el General Marvá -uno de los máximos exponentes del papel de los ingenieros militares en la introducción del hormigón armado en nuestro país-, que presidiría la Comisión encargada del peritaje por parte del juzgado, o las opiniones de reconocidas personalidades internacionales del "nuevo" material como el Dr. von Emperger o Hennebique. Pero lo más relevante de dicha información es la falta de uniformidad sobre lo que pudo ocasionar el hundimiento: fallos en los materiales, durante la construcción, defectos en el diseño de la estructura, la realización de unas pruebas de carga cuando se concluyó ésta, etc. Pero la que durante el juicio y en los Informes posteriores se impuso como causa del fallo de la estructura fue su dilatación como consecuencia de las altas temperaturas que se produjeron aquella primavera. Y ello a pesar de que el hundimiento ocurrió a las 7 de la mañana... Con base en esta información se ha analizado el comportamiento estructural de la cubierta, permitiendo evaluar el papel que diversos factores pudieron tener en el inicio del hundimiento y en su extensión a toda la superficie construida, concluyéndose así cuáles fueron las causas del siniestro. De los resultados obtenidos se presta especial atención a las enseñanzas que se desprenden de la ocurrencia del hundimiento, enfatizándose en la relevancia de la historia -y en particular de los casos históricos de error- para la formación continua que debe existir en la Ingeniería. En el caso del hundimiento del Tercer Depósito algunas de estas "enseñanzas" son de plena actualidad, tales como la importancia de los detalles constructivos en la "robustez" de la estructuras, el diseño de estructuras "integrales" o la vigilancia del proceso constructivo. Por último, la investigación ha servido para recuperar, una vez más, la figura de D. José Eugenio Ribera, cuyo papel en la introducción del hormigón armado en España fue decisivo. En la obra del Tercer Depósito se arriesgó demasiado, y provocó un desastre que aceleró la transición hacia una nueva etapa en el hormigón estructural al abrigo de un mayor conocimiento científico y de las primeras normativas. También en esta etapa sería protagonista. This dissertation analyses the cause of the collapse of the 4th compartment of the 3th Reservoir of Canal de Isabel II in Madrid. It happened in 1905, on April 8th, being one of the most disastrous accidents occurred in the history of Spanish construction: 30 people died and 60 were injured. The design and construction supervision were carried out by D. José Eugenio Ribera, one of the main figures in Civil Engineering of our country, whose career could have been destroyed as a result of this accident. Since it occurred more than 100 years ago, the investigation started by compiling information about the structure`s design and construction, followed by reviewing the available information about the accident. With regard to the construction, it is interesting to point out its daring structural configuration. It covered a huge area of 74.000 m2 with a series of reinforced concrete vaults with a thickness of not more than 5 cm, a 6 m span and a rise of 1/10th. In turn, these vaults were supported by frames composed of very slender 0,25 m x 0,25 m columns with a height of 8 m. It is noteworthy that this took place in a time when the technology and knowledge about this "new" material was largely based on patents. In relation to the information about the collapse, its significance is shown by the important experts and lawyers that were involved in the trial and the subsequent administrative procedure. For example, Echegaray -the most important intellectual of that time- defended Ribera, Melquiades Álvarez –the future president of the Congress- was his lawyer, and General Marvá -who represented the important role of the military engineers in the introduction of reinforced concrete in our country-, led the Commission that was put in charge by the judge of the root cause analysis. In addition, the matter caught the interest of renowned foreigners like Dr. von Emperger or Hennebique and their opinions had a great influence. Nonetheless, this structural failure is unknown to most of today’s engineers. However, what is most surprising are the different causes that were claimed to lie at the root of the disaster: material defects, construction flaws, errors in the design, load tests performed after the structure was finished, etc. The final cause that was put forth during the trial and in the following reports was attributed to the dilatation of the roof due to the high temperatures that spring, albeit the collapse occurred at 7 AM... Based on this information the structural behaviour of the roof has been analysed, which allowed identifying the causes that could have provoked the initial failure and those that could have led to the global collapse. Lessons have been learned from these results, which points out the relevance of history -and in particular, of examples gone wrong- for the continuous education that should exist in engineering. In the case of the 3th Reservoir some of these lessons are still relevant during the present time, like the importance of detailing in "robustness", the design of "integral" structures or the due consideration of construction methods. Finally, the investigation has revived, once again, the figure of D. José Eugenio Ribera, whose role in the introduction of reinforced concrete in Spain was crucial. With the construction of the 3th Reservoir he took too much risk and caused a disaster that accelerated the transition to a new era in structural concrete based on greater scientific knowledge and the first codes. In this new period he would also play a major role.

Historia de la protección del patrimonio arquitectónico en España. 1933-1985

El trabajo de investigación que presentamos tiene como principal objetivo, la recopilación, el registro, el análisis y la reflexión sobre una época, tan trascendental como poco estudiada desde el ámbito arquitectónico, como es el período comprendido entre las dos normas de mayor relevancia en relación a la protección del Patrimonio Histórico Español del último siglo. Nos referimos a la Ley sobre Defensa, Conservación y Acrecentamiento del Patrimonio Histórico Nacional de 13 de mayo de 1933 y la Ley 13/1985, de 25 de junio, del Patrimonio Histórico Español. A través de la investigación realizada, se pretende aportar una visión integral de esta etapa, desde el enfoque arquitectónico, fundamentando la misma en el desarrollo de pautas metodológicas, abordadas desde la recopilación exhaustiva del material bibliográfico y documental para su posterior análisis. A partir de esta fase inicial, se han identificado los nexos comunes entre los estudios existentes sobre el patrimonio monumental español previos a la Guerra Civil y las investigaciones dedicadas a la historia de las últimas décadas del siglo XX. De esta forma, se ha procurado trazar un “puente” documental, con el que trasponer virtualmente el vacío bibliográfico existente. Históricamente, la protección del patrimonio histórico edificado y urbano, ha preocupado y ocupado a multitud de profesionales que, desde disciplinas dispares, han emprendido la tarea ímproba de comprender y explicar cuáles han sido los avatares, históricos y legales, que han marcado su evolución. Tal preocupación ha generado una bibliografía ingente y diversa, desde la protección formal y precisa, sobre uno u otro material, pasando por el marco historiográfico de las tendencias conservacionistas y las teorías decimonónicas, las filigranas formadas por las cuantiosas normas promulgadas desde la Novísima Recopilación, hasta la incidencia del planeamiento urbano en la tutela del patrimonio, incluidas la trama de competencias y yuxtaposiciones administrativas. Documentos de toda índole y profundidad científica, que como mosaicos hispanomusulmanes, dibujan el panorama patrimonial en el que la criba de material resulta una tarea, en ocasiones, inextricable. El título de este documento, en sí mismo, circunscribe la materia que ha sido el objeto de análisis durante el proceso de investigación, el Patrimonio Arquitectónico Monumental. El eje o núcleo basal de estudio se sitúa en los bienes inmuebles, los edificados, que, a su vez, ostentan la declaración de Bien de Interés Cultural, y que, por ende, pertenecen al Patrimonio Histórico Español. La metodología de trabajo se ha desarrollado de forma concéntrica, desde aspectos generales de la protección del patrimonio monumental, como el marco legal que antecede a la promulgación de la Ley de 1933, y el estado previo de los bienes susceptibles de ser preservados. Reconocemos en el ámbito legislativo, el fundamento orgánico que regula y dirige la tutela del patrimonio histórico español y la acción conservadora, y que delimita el ámbito a partir del cual se condiciona el devenir de los bienes culturales. Del esquema de situación surgido del análisis previo, se han detectado los factores claves en la transición hacia la Ley de Patrimonio Histórico Español; la evolución conceptual del “Patrimonio”, como apreciación genérica, y el testimonio de este progreso a través de los valores históricos, artísticos y culturales. El presente documento de investigación, consta de una primera fase, correspondiente al Capítulo 1, que se ha desarrollado a partir, principalmente, de la ordenación jurídica que rige el Patrimonio Histórico Español, a través de leyes, decretos, órdenes y disposiciones anexas, complementado con el material bibliográfico dedicado a la revisión histórica del proceso legal de la protección del patrimonio histórico-artístico. Si bien no ha sido nuestro propósito realizar un estudio pormenorizado del volumen jurídico e histórico que precede a la Ley de 1933, y que da inicio al período de estudio de la presente investigación, sí lo ha sido centrarnos en la elaboración de un extracto de aquellos elementos de la doctrina de mayor relevancia y repercusión en la protección del patrimonio histórico-artístico y/o monumental español. A lo largo de este estudio hemos comprobado lo que algunos juristas ya habían planteado, acerca de la profunda dispersión, ramificación, y diversificación de esfuerzos, tanto en la legislación específica como en la urbanística. Esta disgregación se ha extendido al ámbito de las medidas de reconocimiento caracterizado por la elaboración de múltiples catálogos e inventarios, con desigual transcendencia, alcance y utilidad. El resultado ha sido una división de esfuerzos, desdibujando el objetivo y convirtiendo la acción del reconocimiento en múltiples empresas inconexas y de escasa trascendencia. Nuestra investigación avanza en el análisis de la protección del patrimonio, como concepto globalizador, con el desarrollo del Capítulo 2, en el que se incluye una serie de mecanismos directos e indirectos que, individualmente, suelen carecer de la fuerza efectiva que muchos de los monumentos o conjuntos monumentales requieren para sobrevivir al paso del tiempo y sus circunstancias. En primer lugar, en este segundo capítulo nos hemos centrado, específicamente, en el mecanismo regulado por la Ley del Patrimonio Histórico Español, y el régimen general de protección implementado a partir de su promulgación en 1985. En especial, consideraremos la declaración de Interés Cultural como grado máximo de protección y tutela de un bien, y su posterior inscripción en el Registro General correspondiente, dependiente del Ministerio de Educación, Cultura y Deporte. Este mecanismo representa el instrumento por antonomasia que condensa las facultades de tutela del Estado sobre un bien del que se considera poseedor y aglutinador de valores “culturales” —como cohesión de los valores históricos, artísticos, sociales, etc. — representativos de la idiosincrasia española, y sobre el cual no existen dudas sobre la necesidad de garantizar su permanencia a través de su conservación. En segunda instancia, hemos analizado el Planeamiento Urbanístico, como aglutinador de valores culturales contenidos en la ciudad y como contenedor de los efectos generados por el hombre a partir de su interacción con el medio en el que habita y se relaciona. En tercer término, hemos recopilado y estudiado la concepción de los catálogos, como noción genérica de protección. Desde hace siglos, este género ha estado definido como una herramienta capaz de intervenir en la protección del patrimonio histórico, aunque de una manera difícilmente cuantificable, mediante la identificación, enumeración y descripción de una tipología concreta de monumentos o grupos de ellos, contribuyendo al reconocimiento de los valores cualitativos contenidos en éstos. El tercer capítulo analiza el mecanismo directo de tutela que ejerce la Administración en el patrimonio monumental. La declaración de monumentalidad o de Bien de Interés Cultural y su inclusión en el Registro General de Protección. La protección teórica y la protección jurídica de un monumento, analizadas hasta el momento, resultan tan necesarias como pueriles si no van seguidas de su consumación. En el caso de este tipo de patrimonio monumental, toda acción que tenga como objeto resguardar los valores implícitos en un bien mueble o inmueble, y en su materia, implica el cumplimiento de la protección. Por último, el cuarto capítulo se convierte en el punto culminante, y por ende crucial, del proceso de protección del Patrimonio Cultural, el de la consumación de la intervención. La teoría, la crítica, la normativa y hasta las doctrinas más radicales en materia de protección del patrimonio cultural, carecen de sentido si no las suceden los hechos, la acción, en antítesis a la omisión o la desidia. De ello ha dado pruebas elocuentes la propia historia en multitud de ocasiones con la destrucción, por indolencia o desconocimiento, de importantes vestigios del patrimonio arquitectónico español. Por este motivo, y para ser consecuentes con nuestra tesis hemos recuperado, concentrado y analizado la documentación de obra de tres monumentos imprescindibles del patrimonio construido (la Catedral de Burgos, el Palacio-Castillo de la Aljafería en Zaragoza y la Muralla de Lugo). En ocasiones, al examinar retrospectivamente las intervenciones en monumentos de gran envergadura, física y cultural como catedrales o murallas, algunos investigadores han tenido la sospecha o prevención de que las actuaciones no han seguido un plan de actuación premeditado, sino que han sido el resultado de impulsos o arrebatos inconexos producto de la urgencia por remediar algún tipo de deterioro. En oposición a esto, y a través del estudio de las intervenciones llevadas a cabo en los tres monumentos mencionados, hemos podido corroborar que, a excepción de intervenciones de emergencia fruto de circunstancias puntuales, existe coherencia desde el proceso de análisis de situación de un bien a la designación de prioridades, que ha regido el proceso restaurador a lo largo de dos siglos. La evolución de las intervenciones realizadas en los monumentos analizados ha estado definida, además de por su complejidad, magnitud y singularidad constructiva, por el devenir de su estructura y su uso. En conclusión, la efectividad de la protección del patrimonio cultural español, radica en la concomitancia de múltiples aspectos, entre ellos: el cumplimiento acertado de las normas vigentes, específicas y accesorias; el conocimiento del bien y de sus valores históricos, artísticos, y culturales; su catalogación o inclusión en los inventarios correspondientes; el compromiso de los agentes e instituciones de los cuales depende; la planificación de las tareas necesarias que garanticen tanto la salvaguarda estructural como la conservación de sus valores; y la incorporación de un plan de seguimiento que permita detectar eventuales peligros que atenten contra su conservación. Pero, la situación óptima estaría dada por un sistema en el que estos mecanismos —regulaciones específicas y urbanísticas, Declaraciones de Bien de Interés Cultural, Catálogos e Inventarios, etc. — funcionaran, de forma parcial o total, como una maquinaria, donde cada pieza operara con independencia relativa, pero en sintonía con los demás engranajes. Hasta el momento, la realidad dista mucho de esta situación, convirtiendo esta convivencia en una utopía. Tanto los legisladores, como las autoridades y los técnicos involucrados, deben tener presente que, de ellos, de los parámetros asignados por la legislación, de la implementación de los instrumentos estipulados por ésta y de las decisiones tomadas por cada uno de los poderes directivos de los órganos competentes, dependerá el alcance y efectividad de la protección, ya que en cada vertiente existe, en mayor o menor medida, un porcentaje de interpretación y subjetividad. ABSTRACT The research that we present has as the main objective to collect, record, analyzed and reflection on a time, that was little studied from the architectural field. It is the period between the two laws of most relevance to the protection of Spanish Historical Heritage of the last century. We refer to the Law on the Protection and Conservation of National Heritage of 1933 and Law 16/1985 of Spanish Historical Heritage. Through this research, it aims to provide a comprehensive view of the stage from the architectural approach, basing it on the development of methodological guidelines. The investigation was initiated by the bibliography and documentary for further analysis. After this initial phase, we have identified the common links between existing studies on the Spanish architectural heritage prior to the Civil War and dedicated research into the history of the late twentieth century. Thus, we have tried to draw a documental bridge, with which virtually transpose the gap that has existed. Historically, professionals from diverse disciplines have been worried and busy of the protection of the built and urban heritage. They have undertaken the daunting task of understanding and explaining the historical and legal difficulties, which have marked its evolution. This concern has generated an enormous and diverse literature, from formal and precise protection, in the framework of conservation historiographical trends and nineteenth-century theories. Also, they have studied the impact of urban planning in the protection of heritage, including the competences and administrative juxtapositions. They have generated a lot of documents of all kinds and scientific depth. The title of this document, in itself, circumscribes the matter that has been analyzed during this research process, the Monumental Architectural Heritage. The basal studio is located in the historical buildings, which, in turn, hold the declaration of cultural interest, and thus belong to the Spanish Historical Heritage. The work methodology was developed concentrically from general aspects of the protection of monuments, such as the legal framework that predates the enactment of the 1933 Act, and the previous state of the monuments that should be preserved. We recognize in the legislative sphere, the organic base that regulates and directs the tutelage of Spanish heritage and conservative action. The situation scheme emerged from the previous analysis, and we detected the key factors in the transition to the Spanish Historical Heritage Act; the conceptual evolution of the Heritage as a generic assessment, and witness this progress through historical, artistic and cultural values. This research paper consists of a first phase, corresponding to Chapter 1, which has developed from the legal regulation governing the Spanish Historical Heritage, through laws, decrees, orders and related provisions, supplemented the bibliography dedicated to the historical review of the legal process of protecting historical and artistic heritage. While it was not our intention to conduct a detailed study of the legal and historical volume preceding the 1933 Act, and that started the study period of this investigation, yes he has been focusing on the production of an extract from those elements of the doctrine with greater relevance and impact on the protection of Spanish art-historical and / or architectural heritage. Throughout our study we have seen what some jurists had already raised, about the scattering, branching and diversification of efforts, both in specific law and in urban law. This disaggregation has been extended to the field of recognition measures characterized by the development of multiple catalogs and inventories, with varying significance, scope and usefulness. The result has been a division of efforts, blurring the objective and turning the action of the recognition in multiple attempts little consequence. Our research advances in the analysis of heritage protection, as globalization concept in the Chapter 2, which includes a number of direct and indirect mechanisms that individually, often lack the effective force that many of monuments have required to survive the test of time and circumstances. First, in this second chapter we focused specifically on the mechanism regulated by the Spanish Historical Heritage Act, and the general protection regime implemented since its enactment in 1985 . In particular, we consider the declaration of cultural interest as maximum protection and protection of cultural assets, and their subsequent entry in the relevant General Register under the Ministry of Education, Culture and Sports . This mechanism is the instrument par excellence that condenses the powers of state care about a cultural asset, and which represents the cohesion of the historical, artistic, social values , etc. Secondly, we analyzed the Urban Planning, as a unifying cultural value in the city and as a container for the effects caused by man from its interaction with the environment in which he lives and relates. Thirdly, we have collected and studied the origin of catalogs, as generic notion of protection. For centuries, this genre has been defined as a tool to intervene in the protection of historical heritage, although difficult to quantify, through the identification, enumeration and description of a particular typology of monuments, and that contributing to the recognition of qualitative values contained therein. The third chapter analyzes the direct mechanism of protection performed by the Administration in the monuments with the statement of Cultural asset and inclusion in the General Protection Register. The theoretical and legal protection of a monument is as necessary as puerile if they are not followed by intervention. For this type of architectural heritage, any action which has the aim to safeguard the values implicit in the cultural asset involves protection compliance. Finally, the fourth chapter becomes the highlight, because it treated of the end process of the cultural heritage protection, the consummation of the intervention. The theory, the criticism, the rules and even the radical doctrines on the protection of cultural heritage, are meaningless if they do not take place the facts, the action, in antithesis to the omission. The history of the architectural heritage has given eloquent proof by itself. A lot of vestiges have been lost, in many times, for the destruction, through indolence or unknowledge. For this reason, and to be consistent with our thesis, we have collected and analyzed the projects documentation of three monuments (the Burgos Cathedral, the Aljafería Palace-Castle in Zaragoza and the Wall of Lugo). Sometimes, some researchers have suspected that there had not been planning. They suspect that the projects have been the result of different emergency situations. In opposition of this, we confirm that, except for emergency interventions result of specific circumstances, there have been a process of analysis to conclude in the priorities designation, which has guided the restoration process over two centuries. The complexity, magnitude and constructive uniqueness have defined the evolution of intervention. In conclusion, the effectiveness of the protection of Spanish cultural heritage lies in the conjunction of many aspects, including: the successful implementation of existing, specific and ancillary standards; the knowledge of good and its historical, artistic and cultural values; the cataloging and inclusion in the relevant inventories; and the commitment of the actors and institutions on which it depends. These planning tasks are necessary to ensure both structural safeguards as conservation values; and the introduction of a monitoring plan to detect possible dangers that threaten its conservation. But, the optimal situation would be given by a system in which these urban-regulations and specific mechanisms, would work together like a machine, where each piece operated with relative independence, but in tune with the other gears. So far, the reality is far from this situation, turning this coexistence in a utopia. Both legislators and officials and technicians involved must be aware that the effectiveness and scope of protection depends on your insight and commitment.

Las casualidades controladas : la primera visibilidad del cambio del paradigma moderno

Como no pocos proyectos, el origen de esta tesis es fruto de una casualidad. Hace unos años me topé en Londres, en la librería Walden Books del 38 de Harmood St., con una primera edición de la conocida monografía de Mies a cargo de Philip Johnson. El librito, en realidad catálogo de la exposición que en 1947 el MoMA de Nueva York dedicara a la obra de Mies Van der Rohe a los diez años del desembarco del arquitecto en Estados Unidos, tiene un tamaño de 10 x 7,5 pulgadas, es decir, la mitad del formato americano Crown (20x15 pulgadas), equivalente a 508 x 381 mm. Se imprimieron, en su primera tirada, editada por The Plantin Press, 12.000 ejemplares. Ese mismo año, con edición al cuidado de Reynal y Hitchcock, se publicaría la primera traducción al inglés de Cuando las catedrales eran blancas de Le Corbusier y una selección de poemas de Lorca, siete años después de su Poeta en Nueva York. En la monografía, en la página 109, aparece el conocido croquis de Mies Sketch for a glass house on a hillside. c. 1934, escasamente unas líneas, aunque precisas y llenas de matices, de la casa en una ladera que rápidamente nos remite a aquella primera propuesta de Saarinen para una casa en el aire, primero en 1941 en Pensilvania y después, en 1945, con Charles Eames, en Los Angeles, que nunca llegarían a construirse, sino en su aliteraciones posteriores realizadas por Harry Seidler (Julian Rose House, Wahroonga, Sydney, 1949), Philip Johnson (Leonhardt house, Long Island, Nueva York, 1956) o Craig Ellwood (Smith House, Crestwood Hills, 1958; Frank & Polly Pierson House, Malibú, 1962; Chamorro House, Hollywood Hills, 1963, o la serie Weekend House, con Gerald Horn, entre 1964 y 1970, hasta el magnífico Art Center College of Design de Pasadera, su puente habitado de 1977). El relato que da origen al texto discurre en un estricto período de tiempo, desde los primeros dibujos de la Case Study House nº8, dentro del programa promovido por John Entenza y su revista Arts & Architecture en California, realizados en el estudio de Saarinen en Bloomfield Hills, Michigan, hasta que el proyecto de la casa Eames finaliza cinco años después de acabar la obra en 1955, en la versión conocida, radicalmente distinta al proyecto original, cuando la pareja Charles y Ray Eames edita el corto House After Five Years of Living. La discusión original en torno a esta casita, o mejor, a las circunstancias, casualidades controladas, que rodean su construcción, se produce estrictamente cuando rastreamos aquellos invariantes que se mantienen en las dos versiones y las reconcilian. En este corto período de tiempo se producen en el proyecto una serie de decisiones que permiten descubrir, tanto en la forma como en el mismo proceso transformador del proyecto, en su obsesivo registro, en los nuevos referentes asumidos y propuestos, la primera visibilidad del cambio del paradigma moderno. Pero este momento germinal que cristaliza el paso a la postmodernidad no es inédito en la historia de la arquitectura americana. Así, el relato abre su ámbito temporal hasta un nuevo período de cincuenta años que arranca en 1893, año de la celebración en Chicago de la Exposición Internacional Colombina. En la White City de Hunt & McKim y del traidor Burham, Louis Sullivan construye su Golden Doorway en el pabellón de los Transportes. Aquella que visitará Adolf Loos antes de volver, renovado, a Viena; la misma que admirará André Bouillet, representante de la Union Centrale des Arts Decoratifs de Paris, y que deslumbrará en los museos de toda Europa, de París a Moscú en grandes fotografías y maquetas. Hasta que en Finlandia alguien muestra una de esas fotografías a un joven estudiante de diecinueve años en el Instituto Politécnico. Eliel Saarinen queda fascinado por la poderosa novedad de la imagen. Cuelga la fotografía frente a su tablero de dibujo, consciente de que la Golden Doorway, esa puerta de la aventura y la catarsis que Sullivan acuñaría como distintivo y que resolvería como único elemento complejo sus proyectos más maduros, desprovistos de todo ornamento; la misma que repetirían más tarde, con profundo reconocimiento, Ladovsky, Wright, Scarpa o Moneo, puerta dentro de puerta, fuelle y umbral, contenía, en sus propias palabras emocionadas, todo el futuro de la arquitectura. Desde ahí, pasando por el año 1910, momento de la huida de Wright a La Toscana y el descubrimiento de su arquitectura en Europa, entre otros por un joven Mies van der Rohe, meritorio en el estudio de Peter Behrens, a través del Wasmuth Portfolio; y así como algo después, en 1914, Schindler y en 1923 Neutra, harán el camino inverso, hasta que Mies les siga en 1937, animado por un Philip Johnson que había viajado a Europa en 1930, volviendo a 1945 y el inicio del programa Case Study House en California, hasta 1949, momento de la construcción de la CSH#8, y, por fin, al año 1955, after 5 years of living, en el que Julius Shulman fotografía la casa de Ray y Charles Eames en el prado de Chautauqua sobre las Pacific Palisades de Los Angeles, lanzando sus finas líneas amarillas hasta Alison y Peter Smithson y su tardomoderno heroico, hasta el primer Foster y su poético hightech y hasta el O-riginal Ghery, deconstruyendo el espacio esencial de su casa desde el espacio mismo, abiertas ya las puertas al nuevo siglo. Y en estos cambios de paradigma, desde el rígido eclecticismo de los estilos al lirismo moderno en el gozne secular y de ahí a la frivolidad, ligereza, exhibicionismo y oportunismo cultos del hecho postmoderno, hay algo que se mantiene invariante en los bandazos de la relación del hombre contemporáneo con su entorno. Como la escultura, que según Barnett Newman no es sino aquello contra lo que uno choca cuando retrocede para mirar un cuadro, en estos prístinos lugares, comunes y corrientes, recorrido, puerta, umbral, recinto y vacío, te topas con la arquitectura antes de darte cuenta de que es arquitectura. ABSTRACT As with many other projects, the origin of this doctoral thesis is the result of a chance. A few years ago I found in a bookstore in London, 38 Harmood st., Walden Books, a first edition of the well-known monograph about Mies by Philip Johnson. The tiny book, in fact a catalog of the exhibition that the MoMA of New York devoted to the work of Mies van der Rohe in 1947, ten years after his landing in the United States, has a size of 10 x 7.5 inches, that is, half of Crown American format (20 x 15 inches), equivalent to 508 x 381 mm. In the first printing, published by The Plantin Press, 12,000 copies were released. That same year, produced by Reynal and Hitchcock, both the first English translation of When the cathedrals were white by Le Corbusier and a selection of poems by Lorca were published, seven years after his Poet in New York. Inside the book, the famous drawing from Mies Sketch for a glass house on a hillside c. 1934 appears on page 109, barely a few lines, precise and nuanced though, the house on a hillside that quickly reminds us of the proposals of Eero Saarinen for a house in the air, first in 1941, in Pennsylvania, and later, in 1945, with Charles Eames, in Los Angeles, that would never be built, but in their later alliterations made by Harry Seidler (Julian Rose House, Wahroonga, Sydney, 1949), Philip Johnson (Leonhardt house, Long Island, New York, 1956) or Craig Ellwood (Smith House, Crestwood Hills, 1958; Frank Pierson & Polly House, Malibu, 1962, Chamorro House, Hollywood Hills, 1963, or the Weekend House series, with Gerald Horn, between 1964 and 1970, to the magnificent Art Center College of Design Pasadena, the inhabited bridge, in 1977). The story that gives rise to the text flows in a short amount of time, from the first drawings of the Case Study House No. 8, within the program promoted by John Entenza and his magazine Arts & Architecture in California, made in the study of Saarinen in Bloomfield Hills, Michigan, until the project of the Eames house is completed five years after finishing the construction in 1955, in the final version we know, radically different from the initial state, when the couple, Charles and Ray, published the film House after Five Years of Living. The original discussion around this house, or better, about the circumstances, controlled coincidences, regarding its construction, appears when one takes account of those that remain, the invariants, in the two versions, drawn and built, which precisely allow the reconciliation between both projects. In this short period of time a series of decisions made in the transformation process of the project reveal, in the obsessive record made by Charles Eames and in the new proposed references, the first visibility of the changing of the modern paradigm. But this germinal moment that crystallizes the transition to postmodernism is not unprecedented in the history of American architecture. So, the story opens its temporal scope to a fifty-year period that started in 1893, date of the celebration of the Chicago World´s Columbian Exposition. In the White City by Hunt & McKim and Burnham, the traitor, Louis Sullivan builds his Golden Doorway in the Transportation Building. That visited by a renovated Adolf Loos before his coming back to Vienna; the same that André Bouillet, Head of the Union Centrale des Arts Decoratifs in Paris, admired and dazzled in museums all over Europe, from Paris to Moscow, in large photographs and models. Until someone in Finland showed one of those photos to a young nineteen-years-old student at the Polytechnic Institute. Eliel Saarinen became fascinated by the powerful new image: he hanged the picture in front of his drawing board, aware that the Golden Doorway, that door of adventure and catharsis Sullivan coined as distinctive and as a single complex element which would solve their most mature projects, devoid of all ornament; the same that would repeat later, with deep appreciation, Ladovsky, Wright, Scarpa, or Moneo, a door inside a door, a threshold, a gap that contained, in its own moving words, the whole future of architecture. From there, through 1910, when Wright's flight to Tuscany allows Europe to discover his architecture, including a young Mies van der Rohe, meritorious in the studio of Peter Behrens, via the Wasmuth Portfolio; and as a little bit later, in 1914, Schindler and Neutra in 1923, made the travel in opposite direction, until Mies follows them in 1937, led by a Philip Johnson who had traveled to Europe in 1930, we return to 1945 and the beginning of the program Case Study House in California, and from 1949, when construction of the CSH # 8 begins, and finally, to 1955, after five years of living, when Julius Shulman photographs the inside of the house with Ray and Charles Eames, and all their belongins, at the Chautauqua meadows on Pacific Palisades in Los Angeles, launching its fine yellow lines to Alison and Peter Smithson and his heroic late modern, up to the first Foster and his poetic hightech and even the O-riginal Gehry, deconstructing the essential space of his home from the space itself, opening the doors to the new century. And these paradigm shifts, from the hard eclectic styles to modern secular lyricism in the hinge and then overcoming the cultured frivolity, lightness, exhibitionism, and opportunism of the postmodern skeptical focus, something remains intense, invariant in the lurching relationship of contemporary man and his environment. As the sculpture, which according to Barnett Newman is what you bump into when you back up to see a painting, in these pristine, ordinary places, promenade, door, threshold, enclosure and emptiness, you stumble upon the architecture even before realizing that it is architecture.

Structural factors controlling ligand binding to myoglobin: A kinetic hole-burning study

Using temperature-derivative spectroscopy in the temperature range below 100 K, we have studied the dependence of the Soret band on the recombination barrier in sperm whale carbonmonoxy myoglobin (MbCO) after photodissociation at 12 K. The spectra were separated into contributions from the photodissociated species, Mb*CO, and CO-bound myoglobin. The line shapes of the Soret bands of both photolyzed and liganded myoglobin were analyzed with a model that takes into account the homogeneous bandwidth, coupling of the electronic transition to vibrational modes, and static conformational heterogeneity. The analysis yields correlations between the activation enthalpy for rebinding and the model parameters that characterize the homogeneous subensembles within the conformationally heterogeneous ensemble. Such couplings between spectral and functional parameters arise when they both originate from a common structural coordinate. This effect is frequently denoted as “kinetic hole burning.” The study of these correlations gives direct insights into the structure–function relationship in proteins. On the basis of earlier work that assigned spectral parameters to geometric properties of the heme, the connections with the heme geometry are discussed. We show that two separate structural coordinates influence the Soret line shape, but only one of the two is coupled to the enthalpy barrier for rebinding. We give evidence that this coordinate, contrary to widespread belief, is not the iron displacement from the mean heme plane.

A role for TFIIH in controlling the activity of early RNA polymerase II elongation complexes

TFIIH is a multifunctional RNA polymerase II transcription factor that possesses DNA-dependent ATPase, DNA helicase, and protein kinase activities. Previous studies have established that TFIIH enters the preinitiation complex and fulfills a critical role in initiation by catalyzing ATP-dependent formation of the open complex prior to synthesis of the first phosphodiester bond of nascent transcripts. In this report, we present direct evidence that TFIIH also controls RNA polymerase II activity at a postinitiation stage of transcription, by preventing premature arrest by very early elongation complexes just prior to their transition to stably elongating complexes. Unexpectedly, we observe that TFIIH is capable of entering the transcription cycle not only during assembly of the preinitiation complex but also after initiation and synthesis of as many as four to six phosphodiester bonds. These findings shed new light on the role of TFIIH in initiation and promoter escape and reveal an unanticipated flexibility in the ability of TFIIH to interact with RNA polymerase II transcription intermediates prior to, during, and immediately after initiation.

Two-dimensional freezing in the liquid–vapor interface of a dilute Pb:Ga alloy

We report the results of x-ray reflectivity and grazing incidence x-ray diffraction studies of the liquid–vapor interface of a dilute alloy of Pb in Ga over the temperature range of 23–76°C. Our data show that the liquid–vapor interface of this alloy is stratified for several atomic diameters into the bulk liquid and that a monolayer of Pb forms the outermost stratum of the interface. Over the temperature range of 23–56°C, the monolayer of Pb is in an ordered hexagonal phase. At about 58°C, this monolayer undergoes a first-order transition to a hexatic phase, which remains stable to 76°C. An analogy between the observed transition and the first-order melting transition in a one-component classical plasma is suggested.

Phototactic Migration of Dictyostelium Cells Is Linked to a New Type of Gelsolin-related Protein

The molecular and functional characterization of a 125-kDa Ca2+-extractable protein of the Triton X-100–insoluble fraction of Dictyostelium cells identified a new type of a gelsolin-related molecule. In addition to its five gelsolin segments, this gelsolin-related protein of 125 kDa (GRP125) reveals a number of unique domains, two of which are predicted to form coiled-coil regions. Another distinct attribute of GRP125 concerns the lack of sequence elements known to be essential for characteristic activities of gelsolin-like proteins, i.e. the severing, capping, or nucleation of actin filaments. The subcellular distribution of GRP125 to vesicular compartments suggests an activity of GRP125 different from actin-binding, gelsolin-related proteins. GRP125 expression is tightly regulated and peaks at the transition to the multicellular pseudoplasmodial stage of Dictyostelium development. GRP125 was found indispensable for slug phototaxis, because slugs fail to correctly readjust their orientation in the absence of GRP125. Analysis of the GRP125-deficient mutant showed that GRP125 is required for coupling photodetection to the locomotory machinery of slugs. We propose that GRP125 is essential in the natural environment for the propagation of Dictyostelium spores. We also present evidence for further representatives of the GRP125 type in Dictyostelium, as well as in heterologous cells from lower to higher eukaryotes.

The vibrational energy flow transition in organic molecules: Theory meets experiment

Most large dynamical systems are thought to have ergodic dynamics, whereas small systems may not have free interchange of energy between degrees of freedom. This assumption is made in many areas of chemistry and physics, ranging from nuclei to reacting molecules and on to quantum dots. We examine the transition to facile vibrational energy flow in a large set of organic molecules as molecular size is increased. Both analytical and computational results based on local random matrix models describe the transition to unrestricted vibrational energy flow in these molecules. In particular, the models connect the number of states participating in intramolecular energy flow to simple molecular properties such as the molecular size and the distribution of vibrational frequencies. The transition itself is governed by a local anharmonic coupling strength and a local state density. The theoretical results for the transition characteristics compare well with those implied by experimental measurements using IR fluorescence spectroscopy of dilution factors reported by Stewart and McDonald [Stewart, G. M. & McDonald, J. D. (1983) J. Chem. Phys. 78, 3907–3915].

Fluxes of Reserve-Derived and Currently Assimilated Carbon and Nitrogen in Perennial Ryegrass Recovering from Defoliation. The Regrowing Tiller and Its Component Functionally Distinct Zones1

The quantitative significance of reserves and current assimilates in regrowing tillers of severely defoliated plants of perennial ryegrass (Lolium perenne L.) was assessed by a new approach, comprising 13C/12C and 15N/14N steady-state labeling and separation of sink and source zones. The functionally distinct zones showed large differences in the kinetics of currently assimilated C and N. These are interpreted in terms of ”substrate” and ”tissue” flux among zones and C and N turnover within zones. Tillers refoliated rapidly, although C and N supply was initially decreased. Rapid refoliation was associated with (a) transient depletion of water-soluble carbohydrates and dilution of structural biomass in the immature zone of expanding leaves, (b) rapid transition to current assimilation-derived growth, and (c) rapid reestablishment of a balanced C:N ratio in growth substrate. This balance (C:N, approximately 8.9 [w/w] in new biomass) indicated coregulation of growth by C and N supply and resulted from complementary fluxes of reserve- and current assimilation-derived C and N. Reserves were the dominant N source until approximately 3 d after defoliation. Amino-C constituted approximately 60% of the net influx of reserve C during the first 2 d. Carbohydrate reserves were an insignificant source of C for tiller growth after d 1. We discuss the physiological mechanisms contributing to defoliation tolerance.

Haploinsufficiency of Sox9 results in defective cartilage primordia and premature skeletal mineralization

In humans, SOX9 heterozygous mutations cause the severe skeletal dysmorphology syndrome campomelic dysplasia. Except for clinical descriptions, little is known about the pathogenesis of this disease. We have generated heterozygous Sox9 mutant mice that phenocopy most of the skeletal abnormalities of this syndrome. The Sox9+/− mice died perinatally with cleft palate, as well as hypoplasia and bending of many skeletal structures derived from cartilage precursors. In embryonic day (E)14.5 heterozygous embryos, bending of radius, ulna, and tibia cartilages was already prominent. In E12.5 heterozygotes, all skeletal elements visualized by using Alcian blue were smaller. In addition, the overall levels of Col2a1 RNA at E10.5 and E12.5 were lower than in wild-type embryos. We propose that the skeletal abnormalities observed at later embryonic stages were caused by delayed or defective precartilaginous condensations. Furthermore, in E18.5 embryos and in newborn heterozygotes, premature mineralization occurred in many bones, including vertebrae and some craniofacial bones. Because Sox9 is not expressed in the mineralized portion of the growth plate, this premature mineralization is very likely the consequence of allele insufficiency existing in cells of the growth plate that express Sox9. Because the hypertrophic zone of the heterozygous Sox9 mutants was larger than that of wild-type mice, we propose that Sox9 also has a role in regulating the transition to hypertrophic chondrocytes in the growth plate. Despite the severe hypoplasia of cartilages, the overall organization and cellular composition of the growth plate were otherwise normal. Our results suggest the hypothesis that two critical steps of the chondrocyte differentiation pathway are sensitive to Sox9 dosage. First, an early step presumably at the stage of mesenchymal condensation of cartilage primordia, and second, a later step preceding the transition of chondrocytes into hypertrophic chondrocytes.

Bond orientational order, molecular motion, and free energy of high-density DNA mesophases.

By equilibrating condensed DNA arrays against reservoirs of known osmotic stress and examining them with several structural probes, it has been possible to achieve a detailed thermodynamic and structural characterization of the change between two distinct regions on the liquid-crystalline phase diagram: (i) a higher density hexagonally packed region with long-range bond orientational order in the plane perpendicular to the average molecular direction and (ii) a lower density cholesteric region with fluid-like positional order. X-ray scattering on highly ordered DNA arrays at high density and with the helical axis oriented parallel to the incoming beam showed a sixfold azimuthal modulation of the first-order diffraction peak that reflects the macroscopic bond-orientational order. Transition to the less-dense cholesteric phase through osmotically controlled swelling shows the loss of this bond orientational order, which had been expected from the change in optical birefringence patterns and which is consistent with a rapid onset of molecular positional disorder. This change in order was previously inferred from intermolecular force measurements and is now confirmed by 31P NMR. Controlled reversible swelling and compaction under osmotic stress, spanning a range of densities between approximately 120 mg/ml to approximately 600 mg/ml, allow measurement of the free-energy changes throughout each phase and at the phase transition, essential information for theories of liquid-crystalline states.

An inhibitor of p34cdc2/cyclin B that regulates the G2/M transition in Xenopus extracts.

The activity of maturation-promoting factor (MPF), a protein kinase complex composed of p34cdc2 and cyclin B, is undetectable during interphase but rises abruptly at the G2/M transition to induce mitosis. After the synthesis of cyclin B, the suppression of MPF activity before mitosis has been attributed to the phosphorylation of p34cdc2 on sites (threonine-14 and tyrosine-15) that inhibit its catalytic activity. We previously showed that the activity of the mitotic p34cdc2/cyclin B complex is rapidly suppressed when added to interphase Xenopus extracts that lack endogenous cyclin B. Here we show that a mutant of p34cdc2 that cannot be inhibited by phosphorylation (threonine-14-->alanine, tyrosine-15-->phenylalanine) is also susceptible to inactivation, demonstrating that inhibitory mechanisms independent of threonine-14 and tyrosine-15 phosphorylation must exist. We have partially characterized this inhibitory pathway as one involving a reversible binding inhibitor of p34cdc2/cyclin B that is tightly associated with cell membranes. Kinetic analysis suggests that this inhibitor, in conjunction with the kinases that mediate the inhibitory phosphorylations on p34cdc2, maintains the interphase state in Xenopus; it may play an important role in the exact timing of the G2/M transition.

Ion heating in transitions to CERC in the stellarator TJ-II

In TJ-II stellarator plasmas, in the electron cyclotron heating regime, an increase in the ion temperature is observed, synchronized with that of the electron temperature, during the transition to the core electron-root confinement (CERC) regime. This rise in ion temperature should be attributed to the joint action of the electron–ion energy transfer (which changes slightly during the CERC formation) and an enhancement of the ion confinement. This improvement must be related to the increase in the positive electric field in the core region. In this paper, we confirm this hypothesis by estimating the ion collisional transport in TJ-II under the physical conditions established before and after the transition to CERC. We calculate a large number of ion orbits in the guiding-centre approximation considering the collisions with a background plasma composed of electrons and ions. The ion temperature profile and the thermal flux are calculated in a self-consistent way, so that the change in the ion heat transport can be assessed.

Towards the Consideration of the U.S. Community College Model to Address the Need for Higher Education Reforms in Ghana

ABSTRACT The higher education systems throughout the continent of Africa are undergoing unprecedented challenges and are considered in crisis. African countries, including Ghana, all have in common ties to their colonial legacy whereby they are confronted with weak policies put in place by their colonizers. Having gained their independence, Africans should now take responsibility for the task of reforming their higher education system. To date, nothing substantial has been accomplished, with serious implications for weakening and damaging the structures of the foundation of their educational systems. This qualitative, single case study utilized a postcolonial theory-critical pedagogy framework, providing guidance for coming to grips with the mindset posed by Ghana's colonial heritage in the postcolonial era, especially in terms of its damaging effects on Ghana's higher education system. The study explores alternative pathways for secondary school students to transition to tertiary education--a problematic transition that currently hinders open access to all and equality in educational opportunity, resulting in a tremendous pool of discontinued students. This transitional problem is directly related to Ghana's crisis in higher education with far reaching consequences. The alternative pathway considered in this study is an adaptation of the U.S. community college model or an integration of its applicable aspects into the current structures of the higher education system already in place. In-depth interviews were conducted with 5 Ghanaian professors teaching at community colleges in the United States, 5 Ghanaian professors teaching at universities in Ghana, and 2 educational consultants from the Ghanaian Ministry of Education. Based on their perspectives of the current state of Ghanaian higher education, analyzed in terms of pedagogy, structure/infrastructure, and curriculum, the participants provided their perceptions of salient aspects of the U.S. community college model that would be applicable to Ghana's situation, along with other recommendations. Access to all, including equality of educational opportunity, was considered essential, followed by adaptability, affordability, practicality, and quality of curriculum content and delivery. Canada's successful adaptation of the U.S. model was also discussed. Findings can help guide consideration of alternative pathways to higher education in Ghana and Africa as a whole.

High Value Lies, Ugly Truths, and the First Amendment

Lying has a complicated relationship with the First Amendment. It is beyond question that some lies – such as perjury or pretending to be a police officer – are not covered by the First Amendment. But it is equally clear that some lies, even intentionally lying about military honors, are entitled to First Amendment protection. U.S. v. Alvarez, 132 S. Ct. 2537 (2012). To date, however, both Supreme Court doctrine and academic commentary has taken for granted that any constitutional protection for lies is purely prophylactic – it protects the liar to avoid chilling truthful speech. This Article is the first to argue, contrary to conventional wisdom, that certain types of lies paradoxically advance the values underlying the First Amendment. Our framework is descriptively novel and doctrinally important insofar as we provide the first comprehensive post-Alvarez look at the wide range of lies that may raise First Amendment issues. Because there was no majority opinion in Alvarez, there is uncertainty about which standard of constitutional scrutiny should apply to protected lies, an issue we examine at length. Moreover, our normative claim is straightforward: when a lie has intrinsic or instrumental value it should be treated differently from other types of lies and warrant the greatest constitutional protection. Specifically, we argue that investigative deceptions – lies used to secure truthful factual information about matters of public concern – deserve the utmost constitutional protection because they advance the underling purposes of free speech: they enhance political discourse, help reveal the truth, and promote individual autonomy. A prototypical investigative deception is the sort of misrepresentation required in order for an undercover journalist, investigator, or activist to gain access to information or images of great political significance that would not be available if the investigator disclosed her reporting or political objectives. Tactical use of such lies have a long history in American journalism and activism, from Upton Sinclair to his modern day heirs. Using the proliferation of anti-whistleblower statutes like Ag Gag laws as an illustrative example, we argue that investigative deceptions are a category of high value lies that ought to receive rigorous protection under the First Amendment. At the same time, we recognize that not all lies are alike and that in other areas, the government regulation of lies serves legitimate interests. We therefore conclude the Article by drawing some limiting principles to our theory.