This paper is mainly focused on the characterisation of a glass material (GM) obtained from the thermal treatment of a bottom ash (BA) produced at the Municipal Solid Waste (MSW) incineration plant of Valorsul. By melting the BA at 1400ºC during 2 hours, and without using any chemical additives, a homogeneous black-coloured glass was obtained. The thermal and mechanical properties of this glass were characterised. The thermal expansion coefficient, measured by dilatometry, was 9-10 x 10-6 per ºC and the modulus of rupture, determined by four-point bending test, was 75±6 MPa, which are similar values to those exhibited by commercial soda-lime-silica glasses used in structural applications. The chemical and the ecotoxicological leaching behaviour of the GM were also analysed. The GM was submitted to a leaching procedure composed of 15 sequential extraction cycles. A liquid/solid (L/S) ratio of 2 l/kg was applied in each cycle. The leachates were filtered through a membrane of PTFE (porosity: 0.45 8m). The filtered leachates were characterised for different chemical parameters and for an ecotoxicological indicator (bacterium Vibrio fischeri). The GM was also submitted to a microwave acidic digestion for the assessment of the total metal content. The crude BA was also submitted to the same experimental procedures. The GM showed levels of chemical emission and ecotoxicity for V. fischeri much lower than those determined for the crude BA. Similar characterisation studies will be pursued with the glass-ceramics produced by adequate thermal treatment of the glass, in order to investigate the effect of the crystallization on the final properties.

The vertical stability of anchored concrete soldier-pile walls is highly influenced by the complexity of the interaction between the different parts of the structure, i.e., wall, anchors, and supported soil mass. The problem is analyzed using upper bound limit analysis through published solutions and proposed closed-form equations. A comparison is made between these equations and numerical limit analyses. An estimate of the theoretical minimum pile resistance required to avoid excavation collapse is presented. Published finite element elastoplastic results are used for comparison.Key words: anchored retaining wall, concrete soldier-pile walls, vertical equilibrium, finite elements, limit analysis, soil-to-wall interface shear forces.

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{Let $X_i$ be i.i.d. r.v.s with heavy-tailed CDF $F(x)$ such that $$1-F(x)=(x/C)^{-1/\gamma}((1+(\beta/\rho)(x/C)^{\rho/\gamma} +\beta'(x/C)^{2\rho/\gamma}(1+o(1))),$$ where $\gamma$ is the tail index ($\gamma>0$), and $\rho<0$ and $\beta$ are the ``second order parameters''. The authors construct an estimator for $\beta$ based on the ``tail moments'' $$M_n^{(\alpha)}=(k)^{-1}\sum_{i=1}^k [łog X_{n-i+1:n}-łog X_{n-k:n}]^\alpha. $$ Consistency and asymptotic normality of the estimator are demonstrated. The small sample properties of the estimator are investigated via simulations.}

The study of different kinds of morphological left-right (L-R) asymmetries in all taxa is a very powerful tool to understand evolution since it is a way to measure the developmentalstability of an organism against environmental perturbations. Excluding every pathologic or subtle asymmetry and all cases of taphonomic distortion, this work focuses only on two
kinds of unambiguous asymmetries: fluctuating and adaptative asymmetry. There are several cases of conspicuous left-right asymmetry in dinosaurs and is probably more common than previously thought. The pneumatic cavities systems in skull and vertebrae of theropodsand sauropods are the most common cases reported. The shape (but not the occurrence) of pneumatic cavities might have been exposed to weak selective pressure becoming more random than other body structures. Asymmetries are rarer in the appendicular bones possibly because it represents a strong handicap in the function of the limbs, consequently in the locomotion of the individual. Teeth counting show many exceptions to the typical L-R symmetry. Peculiar cases of adaptive asymmetry are related with the plates of stegosaurs and the ear displacement in the skull of the troodontids, which may have an important role in the physiology and ecology of the animals. The asymmetric displacement maximizes the surface exposure of the stegosaurs dorsal plates. This is an advantage, either the plates were used for thermoregulation, display or specific identification. Work in progress on the braincases of some troodontids specimens shows asymmetric ear openings, which suggests thatcan be an analogy resulting from convergent evolution between troodontids and strigiformes birds, used for 3D directional acoustics. Asymmetries are more common in animals that develop under stress. Animals that lived under dramatic environmental changes periods—like mass-extinctions episodes are believed to be—should present more asymmetries.
However, much more sampling and time accuracy is required in order to be able to relate dinosaur asymmetries to extinction episodes. Asymmetries show strong intra-individual variation and should be taken in consideration in taxonomical studies.

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The position of a 40 μm wide by 400 μm long cantilever in a microscope was detected by a 32 lines array of 1D amorphous silicon position sensitive detectors (PSD). The sensor was placed in the ocular used for the CCD camera of a microscope and the alignment, focusing and positioning of the cantilever was achieved using the X-Y-Z translation table of the microscope that has a micrometer resolution controller. In this work we present results concerning the micro positioning of a cantilever and its holding structure through the reflected light that is detected by 1D/3D psd and converted to an analog signal proportional to the movement. The signal given by the 32 sensor array was analyzed directly without any electronic readout system or data algorithm. The obtained results show a linear behavior of the photovoltage relating X and Y movement, a non-linearity less than 2% and spatial resolution of 600 μV/μm. © 2006 Elsevier B.V. All rights reserved.