Automatic classification system of Raman spectra applied to pigments analysis

Raman spectroscopy is one of the few non-destructive techniques capable of identifying pigments in art works. Raman spectra contain powerful information that can be used to identify unknown compounds and their chemical structures. However, the analysis of spectral data comes with some difficulties, and therefore the spectral interpretation is not straightforward. Sometimes, there are very little differences in the spectral data concerning to specific identification objectives, for instance, in polymorphic discrimination or in the discrimination of natural and synthetic forms of certain pigments. Moreover, this discrimination is often performed manually so that the process can be repetitive, subjective and particularly time-consuming. The result is an increasing motivation to automate the identification process involved in the classification of pigments in paint. In this paper, we propose a system to automatically classify the spectral data into specific and well-known classes, i.e. reference classes. The proposal is based on a combination of chemometric techniques, which provides a powerful way to achieve spectral separability so that it is possible to discriminate between very similar spectra in an automatic way. In this regard, a decision-making algorithm was specifically developed to select the corresponding reference class with no user input, which was successfully validated using simulated spectra. The implemented methodology was used to classify Raman spectra of pigments commonly present in artist's paints in experimental cases, providing reliable and consistent results. Therefore, the presented system can play a good auxiliary role in the analysts' endpoint classification.Peer ReviewedPostprint (author's final draft

Macromamíferos (suidos) de la cueva de Praducelos (Suegos, Lugo)

[Resumen] El trabajo describe un fragmento mandibular de Sus scrofa, hallado en un relleno de dolina del sistema cárstico fósil de Praducelos (Suegos, Lugo). Aunque fuera de contexto estratigráfico tiene un valor cient{fico relativo ante la escasez de datos sobre la fauna cuaternaria de Galicia.[Abstract] The note describe a find of mandibular fragment Sus Scrofa, irom dolina filling of fossil Karstic system of Praducelos (Suegos, Lugo). Althoug out of stratigraphic context, the find have a relative importance considered the scarcity of information about quaternary galician fauna

La ciudad romana de Turobriga. Un modelo urbano en los Llanos de Aroche (Huelva)

The roman Turobriga, although known by scientists in the middle of 60's, until 1996 no archaeological excavations were conducted therein. As from said year several papers and reports have been issued of diverse field works carried out my members of Area de Arqueología de la Universidad de Huelva. In this paper a synthesis of new evidence is presented regarding historial implications of roman town in the Picos de Aroche territory context, its urban pattern, and special relevance of the evidence obtained in the forum area is giving.Aunque la ciudad romana de Turobriga es conocida en el mundo científico desde mediados de los años setenta, no se había realizado sobre ella ningún tipo de investigación hasta la presencia del Área de Arqueología de la Universidad de Huelva a partir de 1996. Desde entonces se han realizado varias campañas de investigación, de diferente carácter, que han generado varios artículos publicados en Congresos o revistas científicas, así como los preceptivos informes y memorias con los resultados de todas las intervenciones. En este trabajo presentamos una breve síntesis de los avances que se han producido, en especial en lo referente a la significación histórica de Turobriga en el contexto territorial de los Picos de Aroche y en las características de su trama urbana, resaltando especialmente los avances en el área del forum

The US actuarial balance model for the pay-as-you-go system and its application to Spain

The aim of this paper is to formulate an approximation of the US actuarial balance model and apply it to the Spanish public retirement pension system under various scenarios in order to determine a consistent indicator of the system's financial state comparable to those used by the most advanced social security systems. This will enable us to answer the question as to whether there is any justification for reforming the pension system in Spain. This type of actuarial balance uses projections to show future challenges to the financial side of the pension system deriving basically from ageing, the projected increase in longevity and fluctuations in economic activity. If one is compiled periodically it can provide various indicators to help depoliticize the management of the pay-as-you-go system by bringing the planning horizons of politicians and the system itself closer together

Las necrópolis de Onuba

In this work a first global and updated approach on the funerary world of the roman city of Onuba Aestuaria –Huelva– is offered. We present the fi rst synthesis about the situation of different cemeterys in the city from the revision of the data provided by the archaeological interventions carried out mid the Sixties of the last century, between to the incorporation of the last new features related to modern research developed in the Archaeological Zone of Huelva.En el presente trabajo se ofrece un primer acercamiento conjunto y actualizado sobre el mundo funerario de la ciudad de Onuba Aestuaria, identifi cada con la actual capital onubense. Se hace una puesta al día sobre las investigaciones realizadas en este campo y se muestra la primera síntesis sobre la situación de las diferentes necrópolis de la ciudad a partir de la revisión de los datos proporcionados por las intervenciones arqueológicas realizadas desde mediados de los años sesenta de la pasada centuria, junto con la incorporación de las últimas novedades derivadas de la intensa actividad arqueológica que se realiza actualmente en la Zona Arqueológica de Huelva

Olfactory preference for ethanol following social interaction with an intoxicated peer in adolescent rats exposed to ethanol in-utero

Background: Prenatal exposure to ethanol and later socially mediated exposure predicts ethanol intake in human adolescents. Animal rat models indicate that brief interactions with an ethanol-intoxicated peer result in heightened preference for ethanol odor and ethanol intake. Methods: This study assessed preference for ethanol odor in adolescent male rats (observers) following social interaction with an ethanol intoxicated peer (demonstrators) as a function of prenatal ethanol exposure (gestational days 17-20, 1.0 g/kg, intragastric). Social behavior and locomotion during social interaction was also measured. Results: Social investigation was greater in observers that interacted with an intoxicated demonstrator in comparison to those that interacted with a sober peer. Social contact increased when the demonstrator was under the effects of ethanol, but only if the observer had experienced ethanol prenatally. Ethanol inhibited locomotion in the demonstrators. Finally, social interaction with an intoxicated peer during adolescence as well as prenatal ethanol experience increased preference for ethanol odor. Conclusions: Fetal exposure to ethanol mediated by maternal intoxication at late gestation or by interaction with an intoxicated peer at adolescence heightens preference for the chemosensory cues of the drug

Morphological and structural evidences concerning the origin of sheet fractures

[Abstract] Sheet fractures are well and widely developed in massive rocks, i.e., rocks lacking other partings, and they have been discussed in the literature for more than a century. Yet there is no agreement as to their origino Two contrasted interpretations hold sway. Almost without exception, geologist adhere to the pressure release or erosional offloading hypothesis. Engineers and engineering geologist, on the other hand, interpret sheet partings as buckling, i.e., crumpling or bending out of plane, related to compressive stresses, particularly lateral stresses. After a review of nomenclature and a description of the characteristics of sheet fractures, a critique ofprevious explanations of their origin is presented. What are perceived to be critical Enes of structural and morphological evidence. bearing on the origin ofsheet fracture are next reviewed, and this is followed by a discusion of the possible origins of the structures