Application of Deep Compaction Techniques to Liquefaction Prevention

This article analyzes the application of dynamic compaction, vibroflotation and vibroreplacement (stone columns) to liquefaction prevention. The ground types to which they can be applied, the depths that can be reached and the degree of improvement that can be obtained are all studied. Finally, and on the basis of the above, basic guidelines are given for the design of ground improvement with these techniques and for the aforementioned purpose

Rickettsia slovaca Infection: DEBONEL/TIBOLA

Producción CientíficaThis study describes the epidemiological, clinical, and microbiological characteristics of a new tick-borne disease in Spain—Dermacentor-borne necrosis erythema lymphadenopathy (DEBONEL). The clinical presentations include an eschar at the site of the tick bite, surrounded by an erythema and painful regional lymphadenopathy. The disease appears during the colder months and its vector is Dermacentor marginatus (D. marginatus). From January 1990 to December 2004, 54 patients presented at Hospital of La Rioja with these clinical and epidemiological data. The ratio of females to males was 32/22. The average age was 37 years. In all cases tick bites were located on the upper body (90% on the scalp). The median incubation period was 4.7 days. Signs and symptoms were mild in all cases. Only a small number of patients presented mild and nonspecific abnormalities in a complete blood cell count and mild elevation of erythrocyte sedimentation rates and C-protein reactive and liver enzyme levels. Serological evidence of acute rickettsiosis was observed in 19 patients (61%). In 29% sera tested by polymerase chain reactions (PCRs) were positive. The sequence obtained from a PCR product revealed 98% identity with Rickettsia sp. strains RpA4, DnS14, and DnS28. All ticks removed from patients were PCR-positive. Sequencing showed 8 of them identified as R. slovaca and 2 as Rickettsia sp. strains RpA4, DnS14, and DnS28

Aportaciones a la taxonomía del género Asplenium: Anatomía del aparato productor de esporas.

Se ha realizado una descripción de la anatomía del aparato productor de esporas, y de los elementos que lo constituyen, en el género Asplenium, basada en el estudio de nueve especies, representativas de los subgéneros Pleurosorus y Asplenium, secciones Ceterach y Asplenium, greges trichomanes, adiantumnigrum, septentrionale y scolopendrium. En vista de la confusión terminológica que habitualmente se encuentra en los trabajos sobre anatomía de helechos, se presenta un glosario en el que se proponen las defmiciones más adecuadas extraídas de la literatura, así como algunas precisiones a éstas y términos nuevos, en base a nuestros resultados.A description of the anatomy of the sporeproducer mechanism, and the elements that form it in the genus Asplenium has been realized, based on the study of nine species representative, of the subgenera Pleurosorus andAsplenium, sections Ceterach andAsplenium, greges trichomanes, adiantum-nigrum, septentrionale and scolopendrium. . In sight of the terminological confusion that is usually found in works on fern anatomy, a glossary -taken out from literature- is presented, in wich adecuate explanations are proposed, along with some precissions to these and new terms, according to our results

Non-linear dynamic soil response underneath a vertical breakwater subjected to impulsive sea wave actions

A theoretical model of the soil-water-structure interaction involved in a breakwater structure subjected to sea wave actions is presented. The model includes i) soil skeleton-pore fluid interaction governed by the u − pw Generalized Biot formulation [1] including dynamic effects, ii) non-linear soil elastoplastic behaviour described by a novel Generalized Plasticity model [2] coupled with a conservative hyperelastic formulation for the dependence of the elastic stiffness on the stress [3], iii) coupling between the caisson and foundation through a non-linear contact with geometrical compatible formulation incorporating frictional behaviour. The numerical solution of the settled governing equations has been fully developed through the Finite Element Method. Furthermore, a program called ADÍNDICA has been created in M Matlab language. ADÍNDICA is a Spanish acronym for “Caisson Breakwater Dynamic Analysis”. Related numerical analyses are developed with reference to precise boundary value problems of specific physical nature. ADÍNDICA code has been able to reproduce adequately the principal characteristics of the caisson oscillations and instantaneous pore pressure generation relation deduced experimentally. Moreover, ADÍNDICA has been able to reproduce satisfactorily the accumulative settlement behaviour of a vertical breakwater structure subjected to series of sea wave impacts including the correlation between accumulated settlements and residual pore pressure

Dynamics of a map with power-law tail

We analyze a one-dimensional piecewise continuous discrete model proposed originally in studies on population ecology. The map is composed of a linear part and a power-law decreasing piece, and has three parameters. The system presents both regular and chaotic behavior. We study numerically and, in part, analytically different bifurcation structures. Particularly interesting is the description of the abrupt transition order-to-chaos mediated by an attractor made of an infinite number of limit cycles with only a finite number of different periods. It is shown that the power-law piece in the map is at the origin of this type of bifurcation. The system exhibits interior crises and crisis-induced intermittency.Comment: 28 pages, 17 figure

THE "FREELY" FALLING TWO-LEVEL ATOM IN A RUNNING LASER WAVE

The time evolution of a two-level atom which is simultaneously exposed to the field of a running laser wave and a homogeneous gravitational field is studied. The result of the coupled dynamics of internal transitions and center-of-mass motion is worked out exactly. Neglecting spontaneous emission and performing the rotating wave approximation we derive the complete time evolution operator in an algebraical way by using commutation relations. The result is discussed with respect to the physical implications. In particular the long time and short time behaviour is physically analyzed in detail. The breakdown of the Magnus perturbation expansion is shown.Comment: 14 Pages, Late

Cálculo retrospectivo del coeficiente de balasto horizontal a partir de mediciones de desplazamientos en pantallas del Metro de Sevilla

This paper presents an abacus with the values of the coefficient of horizontal subgrade reaction for retaining wall analysis in Seville. The aforementioned values have been extrapolated from the actual behaviour on site of the retaining walls, monitored with inclinometers, during the different excavation stages. A primary analysis is carried out initially using the calculation programs Plaxis, Rido and Cype and Chadeisson values of the coefficient of horizontal subgrade reaction. The comparison and discussion of the achieved results leads us to conclude that the usual calculations with Rido and Cype are not reliable for accurately predicting the actual behaviour of the retaining walls. Due to that a parametric analysis is carried out, varying the values of the coefficient of horizontal subgrade reaction, until finding those which mach better the measured reality. The obtained results are synthesised in an abacus so that the knowledge learnt through experience can be applied in future works.En este artículo se presenta un ábaco con los valores del coeficiente de balasto horizontal para el cálculo de pantallas en Sevilla. Dichos valores se han extrapolado a partir del comportamiento real en obra de las pantallas, medido con inclinómetros, durante las distintas fases de excavación. Se realiza de inicio un análisis primario utilizando los programas de cálculo Plaxis, Rido y Cype y los valores del coeficiente de balasto de Chadeisson. La comparación y discusión de los resultados obtenidos nos lleva a concluir que los cálculos habituales con Rido y Cype no son fiables para predecir adecuadamente el comportamiento real de las pantallas. Por eso se realiza un análisis paramétrico, variando los valores del coeficiente de balasto, hasta dar con aquéllos que mejor reproducen la realidad medida. Los resultados alcanzados se sintetizan en forma de ábaco para que lo aprendido con la experiencia pueda ser aplicado en futuros trabajos

Pseudoaneurisma de la arteria geniculada superior lateral secundaria a artroplastia de rodilla: Aportación de un caso

El pseudoaneurisma es una complicación infrecuente en la cirugía ortopédica de rodilla. Los pocos casos descritos generalmente están en relación con cirugía artroscópica. Presentamos un caso de pseudoaneurisma de la arteria geniculada superolateral secundario a artroplastia de rodilla en un varón de 69 años. El diagnóstico se realizó mediante arteriografía. Se trató con éxito mediante hemostasia y resección química.Pseudoaneurysm is an uncommon complication in knee orthopaedic surgery. There are few cases reported an most of them are secondary to arthroscopic techniques. We report a case of pseudoaneurysm of the superolateral genicular artery after knee arthroplasty in a 69-year-old-man. The diagnosis was made with arteriographay, and treatment was a successful hemostasia and surgical resection