Search results for "ESOL"

Screening and authentication of herbal formulations based on microextraction-assisted voltammetry of microparticles

2015

A simple solid state electrochemical methodology for screening and authentication of herbal formulations is described. The proposed method is based on the recording of the voltammetric response, in contact with aqueous buffers, of microparticulate films of antioxidant compounds resulting from micro-extraction of dried herbal samples with ethanol or acetone. The obtained voltammetric responses led us to differentiate between diverse active components upon application of bivariate and multivariate chemometric techniques. Resolution of herbal preparations containing two or more components is possible when well-separated voltammetric signals are recorded. In favorable cases, such characteristic…

Prospecciones sistemáticas en la Depressió de L’Alcoi (Alacant): analizando las colecciones superficiales

2015

En el siguiente texto se presentan los resultados procedentes de las prospec- ciones llevadas a cabo en el valle medio del río Serpis (Alacant, España) durante la últimas década del siglo XX. Éstas siguen la estrategia donde la organización de las colecciones no sigue el concepto de yacimiento. Por otra parte se presentan las ventajas de la utilización de los Sistemas de Posicionamiento Global (GPS) y los Sistemas de Información Geográfica (SIG) como mecanismo básico no sólo para el tratamiento de las colecciones arqueológi- cas sino también para la actualización de los datos documentados durante las prospeccio- nes llevadas a cabo durante los años 80 y principios de los 90. …

A 45-year sub-annual reconstruction of seawater temperature in the Bay of Brest, France, using the shell oxygen isotope composition of the bivalve Gl…

2020

A reconstruction of sea surface temperature (SST) spanning 45 years (1966–2011) was developed from δ18O obtained from the aragonitic shells of Glycymeris glycymeris, collected from the Bay of Brest, France. Bivalve sampling was undertaken monthly between 2014 and 2015 using a dredge. In total, 401 live specimens and 243 articulated paired valves from dead specimens were collected, of which 24 individuals were used to reconstruct SST. Temperatures determined using the palaeotemperature equation of Royer et al. compared well with observed SST during the growing season between 1998 and 2010 (Pearson’s correlation: p = 0.002, r = 0.760). Furthermore, a significant negative correlation was foun…

Last Glacial Human Settlement in Eastern Cantabria (Northern Spain)

2002

While the excavation of individual sites remains fundamental to the creation of the Palaeolithic archeological record, increasingly the focus of prehistoric research is on human adaptations to and within natural regions. Such a reorientation implies viewing sites and occupations as samples of different suites of activities in various habitats across space and time; it is dependent on the use of radiocarbon to date and relate occupation residues among sites; and it necessitates the application of methods to uncover patterns of human mobility as an integral aspect of subsistence economy, demographic arrangements and social relations. This paper contributes to the regional study of Last Glacia…

Wandering through the Mesolithic. An archaeostatistical approach to explore the mobility patterns in eastern Iberia

2019

Abstract Tracing hunter-gatherer's mobility has been a recurring topic both in anthropological and archaeological literature. Following Binford's approach (1980), ethnographic comparisons have been brought out in order to better understand mobility patterns among Palaeolithic and Mesolithic groups, and how they relate with their environment, thus formulating a system where a main difference in mobility structure is pronounced on the distinction between residential and logistical camps. After some efforts made in order to relate the lithic record with such model (Clark and Barton, 2017), in this work we explore how lithic industry can be a reliable proxy for understanding the mobility patter…

The Mediterranean Sea and the Gulf of Cadiz as a natural laboratory for paleotsunami research: Recent advancements

2021

International audience; After the 2004 Indian Ocean (IOT) and the 2011 Tohoku-oki tsunamis, new research in tsunami-related fields was strongly stimulated worldwide and also in the Mediterranean. This research growth yields substantial advancements in tsunami knowledge.Among these advancements is the “Paleotsunami” research that has marked particular progress on the reconstruction of the tsunami history of a region. As an integration of the historical documentation available in the Mediterranean and the Gulf of Cadiz areas, geological and geoarchaeological records provide the insights to define the occurrence, characteristics, and impact of tsunamis of the past. Here, we present the recent …

Ancient DNA provides no evidence for independent domestication of cattle in Mesolithic Rosenhof, Northern Germany

2008

Abstract Recent studies of modern and ancient mtDNA in domesticated and wild cattle has indicated that members of the extinct Near Eastern aurochs population (Bos primigenius primigenius) were the wild progenitors of European domesticated cattle (Bos taurus) (Bollongino, R., Edwards, C.J., Burger, J., Alt, K.W., Bradley, D.G., 2006. Early history of European domestic cattle as revealed by ancient DNA. Biol. Lett. 2, 155–159; Edwards, C.J., Bollongino, R., Scheu, A., Chamberlain, A., Tresset, A., Vigne, J.-D., Baird, J.F., Larson, G., Ho, S.Y.W., Heupink, T.H., Shapiro, B., Freeman, A.R., Thomas, M.G., Arbogast, R.-M., Arndt, B., Bartosiewicz, L., Benecke, N., Budja, M., Chaix, L., Choyke, A…

Characterization and sources of Paleolithic–Mesolithic ochre from Coves de Santa Maira (Valencian Region, Spain)

2020

SINGLE-PEAK RESOLUTION CRITERIA FOR OPTIMIZATION OF MOBILE PHASE COMPOSITION IN LIQUID CHROMATOGRAPHY

2001

Three criteria that evaluate the single peak resolution (peak purity) in chromatography, the free height fraction, free area fraction, and valley ratio, are examined. The main advantages of these criteria against other criteria based on peak pair separation, are that the measurements are not affected by the identity of neighboring peaks and are normalized, which make them very intuitive. The methodology is illustrated through the isocratic separation of mixtures of several sulphonamides (sulphacetamide, sulphadiazine, sulphadimethoxine, sulphaguanidine, sulphamerazine, sulphamethazine, sulphamethoxazole, sulphamethizole, sulphamonomethoxine, sulphanilamide, sulphapyridine, sulphaquinoxaline…

Study of the performance of a resolution criterion to characterise complex chromatograms with unknowns or without standards

2017

The search for best conditions in liquid chromatography is routinely carried out with information provided by chemical standards. However, sometimes there are samples with insufficient knowledge about their chemical composition. In other cases, identities of the components are known, but there are no standards available, and in other cases the identities of peaks in chromatograms taken under different conditions are ambiguous. Most resolution criteria used to measure separation performance cannot be applied to these samples. In this work, a global resolution function valid for all situations was developed based on automatic measurements of peak prominences (area fraction exceeding the line …