Biblioclastía y bibliotecología : Recuerdos que resisten en la ciudad de La Plata

La biblioclastía fue definida como la compulsión humana por destruir libros. Desde tiempos inmemoriales el hombre ha querido imponer sus ideas a través de la destrucción de aquellas que se contraponían a las propias y los libros han sido objeto de esa "pulsión biblioclástica" durante toda la historia de la humanidad. La última dictadura militar que sufrió nuestro país dejó importantes secuelas en la sociedad. Mediante la censura e intervención en diferentes ámbitos (educación, cine, teatro, literatura, entre otros) se construyeron un discurso, un lenguaje y unas prácticas que hoy se reconocen como propias de ese tiempo histórico. Igual que pasó con la desaparición de las personas y sus cuerpos, la represión en el ámbito de la cultura fue parte de un plan sistemático, pensado, calculado y llevado a cabo por dependencias del Estado argentino destinadas a tal fin y por funcionarios (militares y civiles) que fueron parte de ese plan. Se considera de especial importancia que los bibliotecarios, como parte de aquéllos profesionales que contribuyen día a día a la preservación de la memoria, abordemos este tipo de problemáticas y reflexionemos en torno de la mismas. Este trabajo se enmarca en las investigaciones sobre el pasado reciente, teniendo como eje la Declaración Universal de los Derechos Humanos y su postura frente a la libertad de expresión. Intenta reconstruir los mecanismos censorios y cómo se plasmaron en las vivencias de diferentes actores relacionados con el ámbito del libro y del movimiento cultural y político platense, con el objetivo de contribuir a la memoria social de nuestra ciudad.

Biblioclastía y bibliotecología : Recuerdos que resisten en la ciudad de La Plata

La biblioclastía fue definida como la compulsión humana por destruir libros. Desde tiempos inmemoriales el hombre ha querido imponer sus ideas a través de la destrucción de aquellas que se contraponían a las propias y los libros han sido objeto de esa "pulsión biblioclástica" durante toda la historia de la humanidad. La última dictadura militar que sufrió nuestro país dejó importantes secuelas en la sociedad. Mediante la censura e intervención en diferentes ámbitos (educación, cine, teatro, literatura, entre otros) se construyeron un discurso, un lenguaje y unas prácticas que hoy se reconocen como propias de ese tiempo histórico. Igual que pasó con la desaparición de las personas y sus cuerpos, la represión en el ámbito de la cultura fue parte de un plan sistemático, pensado, calculado y llevado a cabo por dependencias del Estado argentino destinadas a tal fin y por funcionarios (militares y civiles) que fueron parte de ese plan. Se considera de especial importancia que los bibliotecarios, como parte de aquéllos profesionales que contribuyen día a día a la preservación de la memoria, abordemos este tipo de problemáticas y reflexionemos en torno de la mismas. Este trabajo se enmarca en las investigaciones sobre el pasado reciente, teniendo como eje la Declaración Universal de los Derechos Humanos y su postura frente a la libertad de expresión. Intenta reconstruir los mecanismos censorios y cómo se plasmaron en las vivencias de diferentes actores relacionados con el ámbito del libro y del movimiento cultural y político platense, con el objetivo de contribuir a la memoria social de nuestra ciudad.

A new set of integrals of motion to propagate the perturbed two-body problem

A formulation of the perturbed two-body problem that relies on a new set of orbital elements is presented. The proposed method represents a generalization of the special perturbation method published by Peláez et al. (Celest Mech Dyn Astron 97(2):131?150,2007) for the case of a perturbing force that is partially or totally derivable from a potential. We accomplish this result by employing a generalized Sundman time transformation in the framework of the projective decomposition, which is a known approach for transforming the two-body problem into a set of linear and regular differential equations of motion. Numerical tests, carried out with examples extensively used in the literature, show the remarkable improvement of the performance of the new method for different kinds of perturbations and eccentricities. In particular, one notable result is that the quadratic dependence of the position error on the time-like argument exhibited by Peláez?s method for near-circular motion under the J2 perturbation is transformed into linear.Moreover, themethod reveals to be competitive with two very popular elementmethods derived from theKustaanheimo-Stiefel and Sperling-Burdet regularizations.

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.

Effect of Carbohydrate Position on Lysosomal Transport of Procathepsin L

To study the role of carbohydrate in lysosomal protein transport, we engineered two novel glycosylation signals (Asn-X-Ser/Thr) into the cDNA of human procathepsin L, a lysosomal acid protease. We constructed six mutant cDNAs encoding glycosylation signals at mutant sites Asn-138, Asn-175, or both sites together, in the presence or absence of the wild-type Asn-204 site. We stably transfected wild-type and mutant cDNAs into NIH3T3 mouse fibroblasts and then used species-specific antibodies to determine the glycosylation status, phosphorylation, localization, and transport kinetics of recombinant human procathepsin L containing one, two, or three glycosylation sites. Both novel glycosylation sites were capable of being glycosylated, although Asn-175 was utilized only 30–50% of the time. Like the wild-type glycosylation at Asn-204, carbohydrates at Asn-138 and Asn-175 were completely sensitive to endoglycosidase H, and they were phosphorylated. Mutant proteins containing two carbohydrates were capable of being delivered to lysosomes, but there was not a consistent relationship between the efficiency of lysosomal delivery and carbohydrate content of the protein. Pulse-chase labeling revealed a unique biosynthetic pattern for proteins carrying the Asn-175 glycosylation sequence. Whereas wild-type procathepsin L and mutants bearing carbohydrate at Asn-138 appeared in lysosomes by about 60 min, proteins with carbohydrate at Asn-175 were processed to a lysosome-like polypeptide within 15 min. Temperature shift, brefeldin A, and NH4Cl experiments suggested that the rapid processing did not occur in the endoplasmic reticulum and that Asn-175 mutants could interact with the mannose 6-phosphate receptor. Taken together, our results are consistent with the interpretation that Asn-175 carbohydrate confers rapid transport to lysosomes. We may have identified a recognition domain in procathepsin L that is important for its interactions with the cellular transport machinery.

O Risco Percebido e Coberto pelas Seguradoras

Os Portugueses desde imemoráveis tempos gostam de partir à descoberta de mundos novos, fazemo-lo pelas mais variadas razões, no entanto, neste trabalho iremos apenas analisar os riscos associados ao turismo de lazer. Os atentados de Nova Iorque em 11 Setembro 2001, Síndrome Respiratório Grave em HongKong em Fevereiro de 2003, o Tsunami no oceano Indico em Dezembro 2004, a erupção vulcânica na Islândia em Abril de 2010 ou os atentados de Paris em 13 de Novembro 2015, estas datas ficaram marcadas para sempre, lemos e relemos inúmeros depoimentos de pessoas que se encontravam de férias nestas cidades e pensamos e se fossemos nós? Os primeiros registos da atividade seguradora datam do ano 5.000 A.C. inicialmente seguravam transportes de mercadorias, hoje em dia podem cobrir “qualquer coisa”. Com a perceção dos riscos que hoje em dia podem ocorrer numa viagem, será que as Seguradoras estão preparadas para minimizar os mesmos? E qual a perceção dos riscos para quem viaja. Para o efeito realizou-se um estudo exploratório por suporte a uma amostra de conveniência que reuniu 152 observações. Análises descritivas e testes não paramétricos foram aplicados para definir quais os riscos mais percebidos e quais os que os turistas portugueses pretendem ver cobertos. Concluiu-se que as pessoas que dão maior importância aos Risco de Saúde e Financeiro são os que efetuam seguros de viagem, já as que dão maior importância aos Risco Equipamento, Risco Politico, Risco Psicológico e Risco de Satisfação são as que optam por não fazer seguro.

Global Waves with Non-Positive Energy in General Relativity

2000 Mathematics Subject Classification: 35Lxx, 35Pxx, 81Uxx, 83Cxx.

An ELISA-like time-resolved fluorescence immunoassay for microcystin detection

Background: A time-resolved fluorescence immunoassay (TRFIA), based on anti-microcystin-LR (MCLR) monoclonal antibodies (MAbs) and europium-labeled antimouse IgG conjugate, was first developed for microcystin detection. Methods: Anti-MCLR MAbs were prepared by a standard method, and the attained MAbs showed a good cross reactivity with MCLR, MCRR and MCYR. The TRFIA was performed in an indirect competitive mode. The detection method of TRFIA was compared with indirect competitive enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). Results: The TRFIA exhibited a typical sigmoidal response for MCLR at concentrations of 0.005-50 ng/ml, with a wide quantitative range between 0.01 and 10 ng/ml, indicating the broadest detective range and the most sensitive of all the methods for microcystins (MCs) detection. Additionally, the TRFIA maintained good reliability through its quantitative range, as evidenced by low coefficients of variation (1.6-12.2%). The toxin data of algal samples assayed from TRFIA were in the same range as those with ELISA and HPLC, implying that the method was reliable and practical for the detection of MCs. Conclusions: The TRFIA may offer a valuable alternative or a substitute for conventional ELISA for microcystin detection. (C) 2004 Elsevier B.V. All rights reserved.

Finite-difference time-domain analysis of deformed square cavity filters with a traveling-wave-like filtering response by mode coupling

An add-drop filter based on a perfect square resonator can realize a maximum of only 25% power dropping because the confined modes are standing-wave modes. By means of mode coupling between two modes with inverse symmetry properties, a traveling-wave-like filtering response is obtained in a two-dimensional single square cavity filter with cut or circular corners by finite-difference time-domain simulation. The optimized deformation parameters for an add-drop filter can be accurately predicted as the overlapping point of the two coupling modes in an isolated deformed square cavity. More than 80% power dropping can be obtained in a deformed square cavity filter with a side length of 3.01 mu m. The free spectral region is decided by the mode spacing between modes, with the sum of the mode indices differing by 1. (c) 2007 Optical Society of America.

Relaxation time and conductivity of comb-like gel polymer electrolytes

Using the copolymer of acrylonitrile (AN), methyl methacrylate (MMA), and poly(ethylene glycol) methyl ether methacrylate as a backbone and poly(ethylene glycol) methyl ether (PEGME) with 1100 molecular weight as side chains, comb-like gel polymers and their Li salt complexes were synthesized. The dynamic mechanical properties and conductivities were investigated. Results showed that the gel copolymer electrolytes possess two glass transitions: alpha-transition and beta-transition. Based on the time-temperature equivalence principle, a master curve was constructed by selecting T. as reference temperature. By reference to T-0 = 50 degrees C, the relation between log c, and c was found to be linear. The master curves are displaced progressively to higher frequencies as the content of plasticizer is increased. The relation between log tau(p) and the content of plasticizer is also linear.

Effects of light-curing time on the cytotoxicity of a restorative composite resin on odontoblast-like cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A peculiar Maxwell's Demon observed in a time-dependent stadium-like billiard

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Purification of a PHA-Like chitin-binding protein from Acacia farnesiana seeds: A time-dependent oligomerization protein

A lectin-like protein from the seeds of Acacia farnesiana was isolated from the albumin fraction, characterized, and sequenced by tandem mass spectrometry. The albumin fraction was extracted with 0.5 M NaCl, and the lectin-like protein of A. farnesiana (AFAL) was purified by ion-exchange chromatography (Mono-Q) followed by chromatofocusing. AFAL agglutinated rabbit erythrocytes and did not agglutinate human ABO erythrocytes either native or treated with proteolytic enzymes. In sodium dodecyl sulfate gel electrophoresis under reducing and nonreducing conditions, AFAL separated into two bands with a subunit molecular mass of 35 and 50 kDa. The homogeneity of purified protein was confirmed by chromatofocusing with a pI=4.0+/-0.5. Molecular exclusion chromatography confirmed time-dependent oligomerization in AFAL, in accordance with mass spectrometry analysis, which confers an alteration in AFAL affinity for chitin. The protein sequence was obtained by a liquid chromatography quadrupole time-of-flight experiment and showed that AFAL has 68% and 63% sequence similarity with lectins of Phaseolus vulgaris and Dolichos biflorus, respectively.

Effects of a mixed vector-scalar kink-like potential for spinless particles in two-dimensional space time

The intrinsically relativistic problem of spinless particles subject to a general mixing of vector and scalar kink- like potentials (similar to tanh gamma x) is investigated. The problem is mapped into the exactly solvable Sturm - Liouville problem with the Rosen - Morse potential and exact bounded solutions for particles and antiparticles are found. The behavior of the spectrum is discussed in some detail. An apparent paradox concerning the uncertainty principle is solved by recurring to the concept of effective Compton wavelength.