Proposal for solid-state particle detector based on latchup effect

A novel approach to detect particles by means of a solid-state device susceptible to latchup effects is described. The stimulated ignition of latchup effects caused by external radiation has so far proven to be a hidden hazard. This is proposed as a powerful means of achieving the precise detection and positioning of a broad range of particles with a spatial resolution of 5 /spl mu/m.     

Accessible e-learning material: a no-frills avenue for didactical experts

Different organizations adopt accessibility for various and diverse reasons. Interesting and inspiring as such reasons may be, it is important to ensure that the motivation for supporting accessibility is that it is the right thing to do, i.e. a commitment to the provision of equal opportunities for accessing resources for people with special needs. Among the various efforts for supporting the development of accessible e-learning material, most of them propose guidelines that prevalently address technical accessibility issues (such as the format and navigation of learning material) with little or no consideration for the didactical experts, and thus their didactical experience, in developing learning material. Moreover, the aforementioned guidelines tend to provide generic indications on alternative forms of didactical content for equivalent access to it. None the less, the sole provision of equivalent forms does not guarantee the retention of desirable user interface aspects and may therefore have a negative impact on learning effectiveness. While this paper acknowledges the role of such guidelines, it does propose that the didactical experts be provided with a non-technical recourse, improving their development of accessible e-learning content. By tapping into the experience of the didactical experts, this work provides them with an avenue leading to enhance the accessibility of e-learning material.     

Dynamic behaviour of an electrolyser with a two phase solid-liquid electrolyte Part II: Investigation of elementary phenomena and electrode modelling

The dynamic behaviour of an electrolyser with a two phase solid-liquid electrolyte was investigated. In a previous paper some results were obtained with high particle concentrations by means of spectral analysis of the electrolyte resistance fluctuations and of the potential fluctuations. Here low bead concentrations were used. This allows potential and electrolyte resistance transients to be well separated and to be studied in the time domain. This analysis gives a detailed view of the approach and residence of the beads near the collector, and a quantitative estimation of the ohmic drop effect for insulating and conductive beads. Ohmic drop fluctuations account for the potential fluctuations for insulating glass beads. Zinc beads behave as insulating particles in the low frequency range and generate a similar ohmic drop effect. They behave as conducting particles in the high frequency range and the fast charge exchange induces depolarizing pulses which favour the formation of compact zinc deposits on the current collector. From the analysis of both transients and PSDs of the electrolyte resistance and potential fluctuations, the mean percentage of the particles colliding with the collector has been estimated even for high bead concentrations.     

Understanding user requirements and preferences for a digital library Web portal

This article reports the findings of a user study conducted in the context of the TELplus project to gain insights about user needs and preferences for the digital library services offered by The European Library Web portal. The user requirements collection for the Web portal was designed by adopting a comprehensive survey approach. This combined explicit user feedback with implicit usage data so as to provide a more in-depth analysis of user experience with the portal. The analysis conducted shed light on likely motivations for both participant usage and reluctance to use the services provided, leading to more informed decisions on how to refine, improve, and present Web portal services to their future users. The lessons learnt from this case study also contributed to the development of an integrated methodological framework which provided insights for the future design and evaluation of digital library Web portals and services.     

Principal component analysis as a tool for studying interdependences among trace metals in edible mussels from the gulf of Trieste

Summary Principal component analysis has been applied to analyze the correlation matrix obtained from a (6 × 44) data matrix. The 6 trace metals are Co, Ni, Cu, Cd, Hg, and Pb, which are contained in the soft part of edible mussels (Mytilus galloprovincialis Lamarck) from a hatchery on the gulf of Trieste. In the space of eigenvectors, the dimensions are reduced to 3 principal axes, which account for about 77% of the total variance.The unrotated factor matrix obtained by the principal components shows that Co, Ni and Cu are bonded to the first principal component, Cd and Pb to the second, Hg to the third. This picture is also assessed by the Varimax-rotated matrix and it is tentatively explained, at least in part, by considering the associations of the trace metals from various geographical sources.

---

Hauptkomponentenanalyse für das Studium der Assoziationen unter Spurenmetallen in Miesmuscheln im Golf von Triest

Zusammenfassung Die Hauptkomponentenanalyse wurde auf die Korrelationsmatrix, die aus der (6 × 44) Datenmatrix hervorgeht, angewandt. Die 6 Spurenmetalle sind Co, Ni, Cu, Cd, Hg, Pb, die im Miesmuschelnfleisch (Mytilus galloprovineialis Lamarck) gefunden werden. Die Miesmuschelnproben stammen aus der Zucht des Golfes von Triest. In dem Eigenvektorraum werden die Dimensionen auf drei Hauptachsen reduziert, die ungefähr 77% der totalen Varianz erklären.Die unrotierte Faktorenmatrix, die aus den Hauptkomponenten hervorgeht, zeigt, daß Co, Ni, Cu an die erste Hauptkomponente, Cd und Pb an die zweite, Hg an die dritte gebunden sind. Dieses Bild wird von der Varimax-rotierten Matrix bestätigt und es findet eine Erklärung in der Herkunft der Spurenmetalle.

     

Computer aided engineering of the sheet bending process

The effects of the punch nose radius and sheet thickness on the elastic springback and residual stresses in the 90° V-punch and U-die bending process of AA 5083 aluminium alloy have been extensively studied by numerical simulations based on the finite element method. The results show that, irrespective of the sheet thickness and punch stroke, the springback ratio is not affected by the punch nose radius. Such results are in excellent agreement with the experimental ones obtained in similar conditions. As far as punch nose radius effects on the residual stresses are considered, significant differences were observed between residual stresses predicted with different nose radii. In particular, the shifting of the neutral layer and increase in the magnitude of the residual stresses predicted by the FEM code were found with decreasing punch nose radius.     

基于值传递的快速故障诊断

本文提出了一种基于值传递的系统模型，重新定义了诊断，该定义与Reiter经典的诊断定义等价。在此基础上，给出了一种线性时间找到一个极小诊断的算法，该方法不需要计算极小冲突而直接得到极小诊断。该算法在给出诊断的同时，还给出了系统与该诊断对应的当前行为的一种合理解释。最后，给出了该方法与诊断测试结合实现系统修复的方法。     

Cytomorphological changes in the rabbit oviductal epithelium after human chorionic gonadotropin treatment

Progenitor cells were isolated from the developing human central nervous system (CNS), induced to divide using a combination of epidermal growth factor and fibroblast growth factor-2, and then transplanted into the striatum of adult rats with unilateral dopaminergic lesions. Large grafts were found at 2 weeks survival which contained many undifferentiated cells, some of which were migrating into the host striatum. However, by 20 weeks survival, only a thin strip of cells remained at the graft core while a large number of migrating astrocytes labeled with a human-specific antibody could be seen throughout the striatum. Fully differentiated graft-derived neurons, also labeled with a human-specific antibody, were seen close to the transplant site in some animals. A number of these neurons expressed tyrosine hydroxylase and were sufficient to partially ameliorate lesion-induced behavioral deficits in two animals. These results show that expanded populations of human CNS progenitor cells maintained in a proliferative state in culture can migrate and differentiate into both neurons and astrocytes following intracerebral grafting. As such these cells may have potential for development as an alternative source of tissue for neural transplantation in degenerative diseases.     

Principal component analysis for the identification of pollution sources in mussel survey by trace metals

Summary Principal component analysis has been applied to analyze the correlation matrix obtained from a 8 × 43 data matrix. The 8 trace metals are Mn, Co, Ni, Cu, Zn, Cd, Hg, Ph, which are contained in the soft part of mussels (Mytilus galloprovincialis Lamarck). Mussels were sampled from two sites in the Gulf of Trieste. In both samples, 76–78% of the total variance is explained by the four principal components. The orthogonally rotated factor matrix indicates that Co and Ni are bonded to the first principal component and Cd and Pb to the first (site 2) or second principal component (site 1). The origin of trace metals in the soft part of mussels from the Gulf of Trieste is discussed.

---

Analyse der Hauptkomponenten zur Identifizierung der Verunreinigungsursachen von Muscheln über die Spurenmetalle

Zusammenfassung Die Analyse der Hauptkomponenten wurde auf die Korrelationsmatrix, die aus der 8 × 43-Datenmatrix hervorgeht, angewandt. Diese 8 Spurenmetalle sind Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb, die im Fleisch der Miesmuscheln (Mytilus galloprovincialis Lamarck) gefunden worden sind. Die Miesmuscheln stammen aus zwei Gegenden des Golfes von Triest. Vier Hauptkomponenten erklären 76–78 % der totalen Varianz der beiden Stichproben. Die orthogonale-rotierte Faktorenmatrix zeigt, daß Co und Ni an die erste Hauptkomponente und Cd und Pb an die erste (Lage 2) oder an die zweite Hauptkomponente (Lage 1) gebunden sind. Die Herkunft der Spurenmetalle im Muschelfleisch aus dem Golf von Triest wird diskutiert.

---

---

L. Felician is the author of the statistical analysis for site 1 as a part of his thesis in Commodity Science, Faculty of Economics, University of Trieste- L. Gabrielli Favretto is the author of the statistical analysis of the data for site 2. All authors contributed to the rest of the paper