Application of near surface mounted (NSM) strengthening technique to traditional timber frame walls

Timber frame buildings are well known as an efficient seismic resistant structure popular all over the world not only due to their seismic performance, but also to their low cost and the strength they offer. These constructions still exist today and it is important to be able to preserve them, so a better knowledge on their behaviour is sought. Furthermore, historic technologies could be used even in modern constructions to build seismic resistant buildings using more natural materials with lesser costs. A great rehabilitation effort is being carried out on this type of buildings, as their neglect has led to decay or their change in use and alterations to the structure has led to the need to retrofit such buildings; only recently studies on their behaviour have become available and only a few of them address the issue of possible strengthening techniques for this kind of walls. In this scope, an innovative retrofitting technique (near surface mounted steel flat bars) is proposed and validated on traditional timber frame walls based on an extensive experimental program. The results of the static cyclic tests on distinct wall typologies retrofitted with the NSM technique are herein presented and discussed in detail. The main features on deformation, lateral stiffness, lateral resistance and seismic performance indexes are analysed

A spectrum-driven damage Identification technique : application and validation through the numerical simulation of the Z24 Bridge

The present paper focuses on a damage identification method based on the use of the second order spectral properties of the nodal response processes. The explicit dependence on the frequency content of the outputs power spectral densities makes them suitable for damage detection and localization. The well-known case study of the Z24 Bridge in Switzerland is chosen to apply and further investigate this technique with the aim of validating its reliability. Numerical simulations of the dynamic response of the structure subjected to different types of excitation are carried out to assess the variability of the spectrum-driven method with respect to both type and position of the excitation sources. The simulated data obtained from random vibrations, impulse, ramp and shaking forces, allowed to build the power spectrum matrix from which the main eigenparameters of reference and damage scenarios are extracted. Afterwards, complex eigenvectors and real eigenvalues are properly weighed and combined and a damage index based on the difference between spectral modes is computed to pinpoint the damage. Finally, a group of vibration-based damage identification methods are selected from the literature to compare the results obtained and to evaluate the performance of the spectral index.

Innovative methodologies for the enhancement of the flexural strengthening performance of NSM CFRP technique for RC beams

Tese de Doutoramento em Engenharia Civil

Microstructure and mechanical properties of carbon nanotube reinforced cementitious composites developed using a novel dispersion technique

The authors also acknowledge Centre for Textile Science and Technology (University of Minho) and FIBRENAMICS PLATFORMfor providing required conditions for this research. Sincere thanks are also due to Mr. Pedro Samuel Leite and Mr. Carlos Jesus for their kind help in sample preparation and testing.

Prediction of drug targets in human pathogens

The identification of new and druggable targets in bacteria is a critical endeavour in pharmaceutical research of novel antibiotics to fight infectious agents. The rapid emergence of resistant bacteria makes today's antibiotics more and more ineffective, consequently increasing the need for new pharmacological targets and novel classes of antibacterial drugs. A new model that combines the singular value decomposition technique with biological filters comprised of a set of protein properties associated with bacterial drug targets and similarity to protein-coding essential genes of E. coli has been developed to predict potential drug targets in the Enterobacteriaceae family [1]. This model identified 99 potential target proteins amongst the studied bacterial family, exhibiting eight different functions that suggest that the disruption of the activities of these proteins is critical for cells. Out of these candidates, one was selected for target confirmation. To find target modulators, receptor-based pharmacophore hypotheses were built and used in the screening of a virtual library of compounds. Postscreening filters were based on physicochemical and topological similarity to known Gram-negative antibiotics and applied to the retrieved compounds. Screening hits passing all filters were docked into the proteins catalytic groove and 15 of the most promising compounds were purchased from their chemical vendors to be experimentally tested in vitro. To the best of our knowledge, this is the first attempt to rationalize the search of compounds to probe the relevance of this candidate as a new pharmacological target.

Layer-by-layer technique to developing functional nanolaminate films with antifungal activity

The layer-by-layer (LbL) deposition method was used to build up alternating layers (five) of different polyelectrolyte solutions (alginate, zein-carvacrol nanocapsules, chitosan and chitosan-carvacrol emulsions) on an aminolysed/charged polyethylene terephthalate (A/C PET) film. These nanolaminated films were characterised by contact angle measurements and through the determination of water vapour (WVTR) and oxygen (O2TR) transmission rates. The effect of active nanolaminated films against the Alternaria sp. and Rhizopus stolonifer was also evaluated. This procedure allowed developing optically transparent nanolaminated films with tuneable water vapour and gas properties and antifungal activity. The water and oxygen transmission rate values for the multilayer films were lower than those previously reported for the neat alginate or chitosan films. The presence of carvacrol and zein nanocapsules significantly decreased the water transmission rate (up to 40 %) of the nanolaminated films. However, the O2TR behaved differently and was only improved (up to 45 %) when carvacrol was encapsulated, i.e. nanolaminated films prepared by alternating alginate with nanocapsules of zein-carvacrol layers showed better oxygen barrier properties than those prepared as an emulsion of chitosan and carvacrol. These films containing zein-carvacrol nanocapsules also showed the highest antifungal activity (30 %), which did not significantly differ from those obtained with the highest amount of carvacrol, probably due to the controlled release of the active agent (carvacrol) from the zein-carvacrol nanocapsules. Thus, this work shows that nanolaminated films prepared with alternating layers of alginate and zein-carvacrol nanocapsules can be considered to improve the shelf-life of foodstuffs.

Intraaortic balloon pump support during coronary angioplasty. Initial experience

OBJECTIVE: To evaluate the use of the intraaortic balloon (IAoB) in association with coronary angioplasty in high-risk patients. METHODS: Fourteen high-risk patients unresponsive to clinical therapy and with formal contraindication to surgical revascularization were treated by coronary angioplasty, most of which was followed by stenting. All procedures were performed with circulatory support with the IAoB. This study reports the early results and the late findings after 12 months of follow-up. Six patients had multivessel coronary disease; of these, four had left main equivalent lesions and two had unprotected left main coronary artery disease, one of whom had severe "end-vessel" stenosis and the other was a patient with Chagas' disease with single-vessel lesion. Eleven patients had a left ventricular ejection fraction <30%. RESULTS: In 100% of the patients, the procedures were initially successful. Two patients had severe bleeding during the withdrawal of the left femoral sheath. At the end of twelve months, 4 patients were asymptomatic and the others were clinically controlled. There were two late deaths in the 7th and 11th months. CONCLUSION: The combined use of the intraaortic balloon pump and percutaneous coronary angioplasty in high-risk patients with acute ischemic syndromes provides the necessary hemodynamic stability to successfully perform the procedures.

Fontan Operation and the Cavopulmonary Technique: Immediate and Late Results According to the Presence of Atrial Fenestration

OBJECTIVE: To compare immediate and late results in patients with or without fenestration who underwent cavopulmonary anastomosis so that we could assess the efficiency of the technique. METHODS: Sixty-two patients underwent surgery between 1988 and 1999, 41 with fenestration (group I -G I) and 21 without fenestration (group II -G II). Tricuspid atresia was prevalent in group I (23-56%) and single ventricle was prevalent in group II (14-66%). Mean ages at the time of operation were 7.3 years in group I and 7.6 in group II. At late follow-up, mean ages were 10.6 years in group I and 12.8 years in group II. RESULTS: Immediate and late mortality were 7.3% in G-I and 4.7% in G-II. Significant pleural effusion occurred in 41.4% of G-I patients and in 23.8% of G-II patients. Significant pericardial effusion occurred in 29.2% and 14.2%, respectively, in groups I and II. Central venous pressure was greater in G-II, 17.7 cm in H2O, as opposed to 15 cm in G-I. Hospital stay was similar between the groups, 26.3 and 21.8 days, respectively. Cyanosis and arterial insaturation occurred in 5 patients, and 4 patients were in functional class II, all from G-I. At late follow-up, 58 (93.5%) were in functional class I. Sinus rhythm was present in 94%, and pulmonary perfusion was similar in both groups. Eleven patients who underwent spirometry had good tolerance to physical effort. CONCLUSION: Atrial fenestration did not improve the immediate or late follow-up of patients who underwent cavopulmonary anastomosis, and is, therefore, dispensable.

Using one-year claim development to chose a large claim reserving technique

Mestrado em Ciências Actuariais

Los objetos técnicos y los organismos tecnificados. Reflexiones filosóficas, estéticas y políticas sobre la técnica. Technical objects and technified organisms. Philosophical, aesthetical and political approaches on technique

El presente proyecto se propone como parte inicial de una investigación sobre la relación entre naturaleza/cultura/técnica. Tradicionalmente la naturaleza y la cultura se han considerado como ámbitos diferenciados y opuestos. Y es en esta distinción donde la técnica adquiere un lugar central. El pensamiento occidental sobre la técnica ha recibido diversas interpretaciones: desde una subordinación con respecto al conocimiento verdadero (episteme) en la filosofía clásica, un optimismo sobre la técnica como posibilidad de dominación de la naturaleza en el Renacimiento y la Ilustración, y la ambigüedad y desasosiego romántico (Mitcham, 1979). Durante el siglo XX se distinguen dos posiciones antagónicas sobre la técnica. Por un lado, una actitud “crítica” donde pueden identificarse los trabajos de filósofs de diferentes tradiciones como Ortega y Gasset (1939), Heidegger (1954), Mumford (1971) Ellul (1960) y la Escuela de Frankfurt. Por otro lado, una filosofía de la técnica “ingenieril” que consiste en el análisis de la tecnología como un paradigma de pensamiento y acción humana. Esta dicotomía ha sido interpretada por Eco como “apocalípticos e integrados”. Más allá de las mencionadas diferencias, lo que tienen en común ambas posiciones es que parten de una dicotomía entre cultura y naturaleza. Nuestra perspectiva rechaza esta dicotomía, por el contrario, evidenciamos una creciente imbricación entre ambas donde las fronteras entre una y otra se hacen difusas. La noción de “objeto técnico” propuesta por Simondon (2007) hace referencia a la inserción del objeto técnico en la cultura, donde debe reconocerse la “realidad humana” presente en el mismo. Ahora bien, esto no significa “humanizar el objeto técnico”, sino más bien indagar sobre el lugar que este ocupa en la cultura como también establecer su relación con la naturaleza. En el siglo XVII el hombre mismo es reinterpretado como máquina (La Mettrie, 2000). En la actualidad pueden identificarse dos tendencias en la concepción de la técnica: los «humanos-máquinas» y las «máquinas-humanas», en otras palabras, la disposición del humano hacia la máquina y la tendencia de la máquina hacia lo humano. No obstante, ambas posiciones siguen manteniendo una distinción taxonómica entre el cuerpo –o lo orgánico- y lo maquínico, lo que implica una consideración de esta relación de manera extrínseca. Frente a esta tensión Haraway propone el concepto de cyborg: «un organismo cibernético» (1995). Los desarrollos tecnológicos han producido una modificación tal en la vida de los seres orgánicos en los cuales ya no puede concebirse su cuerpo independientemente de la tecnología. Esto conduce a replantear la distinción entre “animales/hombres/máquinas”, entendiendo a los mismos como expresiones de naturaleza, cultura y tecnología respectivamente. Nuestra investigación parte de la hipótesis que la técnica diluye diferencias de orden natural y cultural a través de los objetos técnicos que son productos culturales. La estética se ocupa de la percepción sensible del mundo no puede eludir su dimensión técnica. Al margen de la crítica a la “Industria cultural” consideramos relevante la aproximación de Benjamin al problema de la técnica porque aborda la imbricación antes mencionada en el campo de la percepción. Según Benjamin la irrupción de la técnica al mismo tiempo que posibilita una estetización de la política que confluye en el fascismo como punto extremo también abre la posibilidad de desmontar la ideología del progreso infinito (1967). Una integración entre aproximaciones estéticas y políticas a la técnica Flusser (1983) propone la “caja negra” como metáfora de la técnica contemporánea. Su propuesta es la “apertura de la caja negra” que consiste en tomar conocimiento del funcionamiento del dispositivo. Nuestra propuesta de investigación aborda la técnica desde una consideración filosófica/estética/política, donde redefiniremos la técnica partiendo de la imbricación entre cultura y naturaleza. This project will set the basis for a sustained research on the relation nature/culture/technique. They have been traditionally considered as separate and even opposite fields. And it is on the brink of this distinction where technique plays a central role. In Western thought technique has received many interpretations since the beginnings of philosophy: from a subordination to true knowledge (episteme) in classic philosophy, or the optimism which sees in technique the possibility of dominating nature in the Renaissance and in the Enlightenment, to the Romantic ambiguity and uneasiness towards technological change (Mitcham, 1979). During the twentieth century two opposed approach on technique prevail. On one hand, a “critical” attitude such defines the work of philosophers of different traditions such as Ortega y Gasset (1939), Heidegger (1954), Mumford (1971) Ellul (1960) and the Frankfurt School. On the other hand there is an “engineering” philosophy of technique that consists in the analisis of technology as a paradigm to understand human action and thought. Besides their differences, both positions have in common a dichotomy between nature and culture. We reject such dichotomy. On the contrary we consider there is a growing intertwinement between both which blurs the borders of the concepts. Simondon’s notion of “technical object” refers to the insertion of the technique in culture where the “human reality” in it must be recognised. This does not imply “humanising the technical object”, but investigate on the role it plays on culture and establishing its relation to nature. To articulate this relation we will work with unorthodox approaches on technique such as Benjamin (1967), Flusser (1983) and others. The hypothesis of our project is that the traditional distinction of “animal/man/machine” must be re-thought, therefore raising the question on the blurring line between nature, culture and technique and its effects in philosophy, politics and aesthetics.

Espectroscopía de emisión de rayos x. Aplicación a la caracterización de materiales. X-ray emission spectroscopy. Application to materials characterization

La idea principal del proyecto abarca el estudio de parámetros y fenómenos físicos. Los avances logrados se aplicarán al desarrollo de software y metodologías para cuantificación de materiales mediante microanálisis con sonda de electrones y microscopía electrónica de barrido. El microanálisis no es una técnica absoluta, sino que requiere de estándares de referencia, para obviar el uso de ciertos parámetros geométricos y atómicos difíciles de conocer con una precisión adecuada. Para contar con un método sin estándares debe abordarse la determinación de parámetros atómicos e instrumentales, que es uno de los aspectos que se desea encarar en este proyecto. Por otro lado, también se pretende incluir los parámetros estudiados en un software de cuantificación desarrollado por integrantes del proyecto. Otro de los propósitos del plan de trabajo es estudiar la potencialidad de la resolución espacial de una microsonda de electrones con el fin de desarrollar una metodología para caracterizar interfases, bordes de granos e inclusiones, con resolución submicrométrica, ya que los métodos tradicionales de cuantificación se restringen al caso de muestras planas y homogéneas dentro del volumen de interacción, pero la caracterización de inhomogeneidades a nivel micrométrico no ha sido desarrollada todavía, salvo algunas excepciones. The main idea of this project involves the study of physical parameters and phenomena. The concretion of the different goals will permit the elaboration of softeare and methodologies for materials characterization by means of electron probe microanalysis and scanning microscopy. Electron probe microanalysis is not an absolute technique, but requires reference standards in order not to involve certain geometrical and atomic parameters for which high uncertainties cannot be avoided. In order to have standardless method, the determination of atomic and instrumental parameters must be accomplished, as will be faced through this project. Complementary, the parameters studied will be included in a quantification software developed in our research group of FaMAF. Another objective of this activity plan is to study the spatial resolution potentiality of a focalized electron beam, with the aim of characterizing interphases, grain boundaries and inclusions with submicron sensitivity, since the traditional quantification procedures are restricted to flat homogeneous samples, whereas the characterization of inhomogeneities has not been developed yet.

Investigation of Copy Number Variation in Children with Conotruncal Heart Defects

Background:Congenital heart defects (CHD) are the most prevalent group of structural abnormalities at birth and one of the main causes of infant morbidity and mortality. Studies have shown a contribution of the copy number variation in the genesis of cardiac malformations.Objectives:Investigate gene copy number variation (CNV) in children with conotruncal heart defect.Methods:Multiplex ligation-dependent probe amplification (MLPA) was performed in 39 patients with conotruncal heart defect. Clinical and laboratory assessments were conducted in all patients. The parents of the probands who presented abnormal findings were also investigated.Results:Gene copy number variation was detected in 7/39 patients: 22q11.2 deletion, 22q11.2 duplication, 15q11.2 duplication, 20p12.2 duplication, 19p deletion, 15q and 8p23.2 duplication with 10p12.31 duplication. The clinical characteristics were consistent with those reported in the literature associated with the encountered microdeletion/microduplication. None of these changes was inherited from the parents.Conclusions:Our results demonstrate that the technique of MLPA is useful in the investigation of microdeletions and microduplications in conotruncal congenital heart defects. Early diagnosis of the copy number variation in patients with congenital heart defect assists in the prevention of morbidity and decreased mortality in these patients.

Technique and clinical applications of double balloon enteroscopy for the evaluation of small bowel diseases

Magdeburg, Univ., Med. Fak., Diss., 2012