Study by SEM-EDS of the in situ dynamic leaching of mercury ores

The present work studies the surface evolution of cinnabar, when it is leached with HBr acid for different conditions. The dynamicin situ test has been studied by scanning electron microscopy and EDS techniques. According to the acid condition, time, and temperature, the HgS presents different mechanisms of dissolution, and the results prove that the cinnabar does not present “memory effect”, as proposed by other authors.¹⁶     

Study by SEM-EDS of the in situ dynamic leaching of mercury ores

The present work studies the surface evolution of cinnabar, when it is leached with HBr acid for different conditions. The dynamicin situ test has been studied by scanning electron microscopy and EDS techniques. According to the acid condition, time, and temperature, the HgS presents different mechanisms of dissolution, and the results prove that the cinnabar does not present “memory effect”, as proposed by other authors.¹⁶     

Using PCA in time-of-flight vectors for reflector recognition and 3-D localization

This paper presents a reflector recognition and localization technique in three-dimensional (3-D) environments, using only times-of-flight (TOFs) data obtained from ultrasonic transducers. The recognition and localization technique is based on the principal component analysis applied to the TOF vectors originating from a sensor that contains two emitting transducers and several receivers. The two emitters simultaneously transmit two coded pulses that are detected later on and discriminated by the receivers, after being reflected in the environment. The proposed technique allows for the possibility of not only recognizing the reflectors, but also estimating approximately its localization referred to the sensor. This technique has been tested with three types of reflectors in 3-D environments: planes, edges, and corners. The achieved results are very satisfactory for reflectors located in the range 50-350 cm.     

Inactivation of glutathione S-transferase P1 gene by promoter hypermethylation in human neoplasia

Glutathione S-transferases (GSTs) are a family of isoenzymes that play an important role in protecting cells from cytotoxic and carcinogenic agents. The pi-class GST has been associated with preneoplastic and neoplastic changes. Recently, it has been reported that regulatory sequences near the GSTP1 gene, which encodes the human pi-class GST, are commonly hypermethylated in prostatic carcinomas. In the present study, we studied more than 300 primary human tumors originating in other organs for aberrant methylation of GSTP1 using methylation-specific PCR. GSTP1 hypermethylation was most frequent in breast and renal carcinoma, showing aberrant methylation in 30 and 20% of the cases, respectively. Other tumor types showed promoter methylation only rarely or not at all. Hypermethylation of GSTP1 was associated with loss of expression demonstrated by immunohistochemistry. Our results suggest that aberrant methylation of GSTP1 may contribute to the carcinogenetic process in breast and renal carcinomas.     

Impacts of High-Speed Rail on Metropolitan Integration: An Examination of London,Madrid and Paris

The original goal of high-speed rail (HSR) was to link large metropolitan regions 400–600?km apart. Recently, however, intermediate ‘ex-metropolitan’ HSR stations have also been created in suburban areas/cities within metropolitan regions (up to 100?km from the metropolitan centre). This study takes a close look at nine such ‘ex-metropolitan’ stations around Madrid (Guadalajara, Segovia, and Toledo), London (Stratford, Ebbsfleet, and Ashford), and Paris (Charles-de-Gaulle, Marne-la-Vallée — Chessy, and Massy), to understand their territorial and local impacts and draw possible lessons for the California High Speed Rail project.     

Teaching equipment for training in the control of DC, brushless,and stepper servomotors

This paper describes teaching equipment for instruction in motor control developed in the Electronics Department of the University of Alcala, Spain. This project (called Project DEDALO) involved the development of complete electronic equipment for studying and carrying out experiments on the control of stepper, medium and low-power DC and brushless motors. The use of a personal computer as user interface (for the setting up of different types of motors and controls, display of the control structures, signal display, generation of commands, etc.) makes the equipment very easy to use and highly versatile     

Tutorial and simulation electrooptic and acoustooptic software as innovative methodology to improve the quality of electronic and computer engineering formation

In this paper, an introduction to the main design features of a computer-aided educational package addressed to students of the final years of Electronic and Computer Engineering is presented. The software includes interrelated tutorial, computer simulations, and test questions in which graphical outputs, hypertexts, and animations are widely used. The package is devoted to the simulation study of electrooptic and acoustooptic theory and devices. It provides instant numerical evaluation and a graphical display of different studies. The software presented in this paper has all the following features: an integrative character, self-evaluation tests, a personalized and active learning process, adaptability to teacher's aims, versatility as a teaching tool, multimedia resources, and simplicity. This study has been completed with final-year students at the Superior Polytechnic School of Cordoba, Spain, with highly favorable results when compared with students who did not use the software.