1,809 research outputs found
Los arrabales de la Córdoba musulmana. De las fuentes escritas a la realidad arqueológica
We present in this report our particular visión about the knowledge situation of islamic Cordoba 's suburbs, departing from a little historiographic analysis and finishing, after explaining the facts we have nomaday thanks to the archeology, with a criticism trought of the present view.Presentamos en este artículo nuestra particular visión del estado de la cuestión sobre los arrabales de la Córdoba musulmana, partiendo de un sucinto análisis historiográfico y concluyendo, tras exponer los datos con que contamos en la actualidad gracias al rigor arqueológico, con una reflexión crítica del panorama actual.Comunicación presentada a: Jornadas Cordobesas de Arqueología Andaluza. Arqueología de Al Andalus: Los palacios islámicos. XI. 2001. Córdob
Minería y metalurgia durante la I Edad del Hierro. Procesos de cambio en el sur de Cataluña
El objetivo de este artículo es ofrecer un breve resumen de la investigación acerca de la minería y la metalurgia en la 1ª Edad
del Hierro del sur de Catalunya, basado en el reciente trabajo de campo y los estudios analíticos en tres áreas: el valle bajo del río Siurana, la Terra Alta-Algars-Matarranya y el curso bajo del Sénia.Se discuten los diferentes procesos de cambio social.The aim of this paper is to present a summary of research concerning mining and metallurgy in the Early Iron Age of southern Catalonia, on the basis of recent fieldwork and analytical studies in three areas: the lower valley of the River Siurana; La Terra Alta-Algars-Matarranya; and the lower course of the River Sénia. Different processes of social change are discussed.Plan Nacional de I+D+I
2004-2007 proyectos ref. HUM 2004-04861-C02 y C03), y HUM2004-03121/HIS
Strontium-isotope stratigraphy as a constraint on the age of condensed levels: examples from the Jurassic of the Subbetic Zone (southern Spain).
Condensed levels are often characterized by reworked fossils that may lead to incorrect age assessments. Strontium-isotope stratigraphy is an important chronostratigraphic tool that can be used to verify the biostratigraphic information from condensed beds. This paper describes a study of the 87Sr/86Sr isotope ratios of 56 belemnite samples collected from 28 stratigraphic sections of the boundary between the Upper Member of the Gavila´n Formation and the Zegrı´ Formation (Pliensbachian, Subbetic Zone). The petrographic and geochemical data (d18O, d13C, concentrations of Fe, Mn and Mg, and the Sr/Mn ratio) suggest that the belemnites have preserved their original marine geochemical composition. After plotting the samples in diagrams of 87Sr/86Sr values against time according to their biostratigraphic age, four different groups (A, B, C and D) were obtained with respect to the reference curve. In groups A and B, the age deduced from the Sr-isotope ratio is in total or partial agreement, respectively, with the biostratigraphic age; therefore the 87Sr/86Sr ratio is a good method for the dating, correlation and assessment of biostratigraphic results. In groups C and D, the SIS age and the biostratigraphic age do not coincide. A graphic procedure is presented as a suitable methodology to constrain the age of the samples showing an SIS age that differs from the relative age deduced (by biostratigraphy or stratigraphic correlation) for the bed they were collected in. These situations are interpreted as being the result of reworking of the belemnites (group C) or ammonites (group D) that are included in condensed levels. These condensed levels formed during the maximum flooding event that led to the drowning of the Gavila´n carbonate platform. The methodology supplied in this paper represents a valuable tool in identifying reworking processes, improving correlation and constraining biochronostratigraphic results. The values of 87Sr/86Sr represent a new contribution to the data set of 87Sr/86Sr ratios for the Pliensbachian
La ruptura de la plataforma carbonatada del Lías Inferior en el Subbético Oriental (Provincias de Murcia y Alicante): Distribución de facies y valores isotópicos del 87Sr/86S r , C y O
The carbonate rocks of the upper part of the Gavilán Fm from the Eastern Subbetic are studied. They have been dated as Early Pliensbachian (carixian) in age and they were deposited in a carbonate platform. The stratigraphic and facies analysis show that the general scheme proposed by Ruiz-Ortiz et al. (2004) for the middle and upper member of the formation, each of them interpreted as a depositional sequence, can be easily applied. Moreover, a third sequence can be differentiated from the unusual record of upper Carixian sediments in some of the studied sections. The evolution of the content in b,3C, b180 and 87Sr/86Sr, is also analyzed from belemnites rostra. The values of these isotope ratios range between their characteristic values for the Pliensbachian according to different authors. Some critical variations can be correlated with those proposed for equivalent ages by other authors
A pyrF auxotrophic mutant of Sinorhizobium fredii HH103 impaired in its symbiotic interactions with soybean and other legumes
Transposon Tn5-Mob mutagenesis allowed the selection of a Sinorhizobium fredii HH103 mutant derivative (SVQ 292) that requires the presence of uracil to grow in minimal media. The mutated gene, pyrF, codes for an orotidine-5´- monophosphate decarboxylase (EC 4.1.1.23). Mutant SVQ 292 and its parental prototrophic mutant HH103 showed similar Nod-factor and lipopolysaccharide profiles. The symbiotic properties of mutant SVQ 292 were severely impaired with all
legumes tested. Mutant SVQ 292 formed small ineffective nodules on Cajanus cajan and abnormal nodules (pseudonodules) unable to fix nitrogen on Glycine max (soybean), Macroptitlium atropurpureum, Indigofera tinctoria, and Desmodium canadense. It also did not induce any macroscopic response in Macrotyloma axillare roots. The symbiotic capacity of SVQ 292 with soybean was not enhanced by the addition of uracil to the plant nutritive solution. [Int Microbiol 2007; 10(3):169-176
Arqueometria antropológica en el sepulcro megalítico de El Palomar: contribución al conocimiento histórico de la campiña sevillana
Presentamos un estudio de la analítica realizada en huesos humanos encontrados en el interior de la estructura dolménica de El Palomar que ha sido realizada en la Universidad Autónoma de Barcelona. Este trabajo se integra en el Proyecto de Investigación que sobre Análisis del Proceso Cultural Operado en las Sociedades Agrarias de la Campiña Sevillana se está llevando a cabo en el Departamento de Prehistoria y Arqueología de la Universidad de Sevilla
Fasciola hepatica induces eosinophil apoptosis in the migratory and biliary stages of infection in sheep
The aim of the present work was to evaluate the number of apoptotic eosinophils in the livers of sheep experimentally infected with Fasciola hepatica during the migratory and biliary stages of infection. Four groups (n = 5) of sheep were used; groups 1–3 were orally infected with 200 metacercariae (mc) and sacrificed at 8 and 28 days post-infection (dpi), and 17 weeks post-infection (wpi), respectively. Group 4 was used as an uninfected control. Apoptosis was detected using immunohistochemistry with a polyclonal antibody against anti-active caspase-3, and transmission electron microscopy (TEM). Eosinophils were identified using the Hansel stain in serial sections for caspase-3, and by ultrastructural features using TEM. At 8 and 28 dpi, numerous caspase-3+ eosinophils were mainly found at the periphery of acute hepatic necrotic foci. The percentage of caspase -3+ apoptotic eosinophils in the periphery of necrotic foci was high (46.1–53.9) at 8 and 28 dpi, respectively, and decreased in granulomas found at 28 dpi (6%). Transmission electron microscopy confirmed the presence of apoptotic eosinophils in hepatic lesions at 8 and 28 dpi. At 17 wpi, apoptotic eosinophils were detected in the infiltrate surrounding some enlarged bile ducts containing adult flukes. This is the first report of apoptosis induced by F. hepatica in sheep and the first study reporting apoptosis in eosinophils in hepatic inflammatory infiltrates in vivo. The high number of apoptotic eosinophils in acute necrotic tracts during the migratory and biliary stages of infection suggests that eosinophil apoptosis may play a role in F. hepatica survival during different stages of infection.This work was supported by EU grants (FPVII-265862-PARAVAC, H2020-635408-PARAGONE) and the Spanish Ministry of Science grant AGL2009-08726. TEM studies were carried out by the Central Services for Research of the University of Córdoba (SCAI)Veterinari
Apoptosis of peritoneal leucocytes during early stages of Fasciola hepatica infections in sheep
Several immunomodulatory properties have been described in Fasciola hepatica infections. Apoptosis has been shown to be an effective mechanism to avoid the immune response in helminth infections. The aim of the present work was to study apoptosis in peritoneal leucocytes of sheep experimentally infected with F. hepatica during the early stages of infection. Five groups (n = 5) of sheep were used. Groups 2–5 were orally infected with 200 metacercariae (mc) and sacrificed at 1, 3, 9 and 18 days post-infection (dpi), respectively. Group 1 was used as the uninfected control (UC). Apoptosis was detected using three different methods 1) immunocytochemistry (ICC) with a polyclonal antibody anti-active caspase-3; 2) an annexin V flow cytometry assay using the Annexin V-FITC/propidium iodide (PI); and 3) transmission electron microscopy (TEM). The differential leucocyte count revealed that the majority of peritoneal granulocytes were eosinophils, which increased significantly at 9 and 18 dpi with respect to the uninfected controls. The ICC study revealed that the percentage of caspase-3+ apoptotic peritoneal leucocytes increased significantly from 3 dpi onwards with respect to the uninfected controls. The flow cytometry annexin V assay detected a very significant (P < 0.001) increase of apoptotic peritoneal macrophages, lymphocytes and granulocytes, which remained higher than in the UC until 18 dpi. Transmission electron microscopy studies also confirmed the presence of apoptosis in peritoneal eosinophils at 18 dpi. This is the first report of apoptosis induced by F. hepatica in the peritoneal leucocytes of sheep in vivo. The results of this work suggest the importance of apoptosis induction for the survival of the juvenile parasites in the peritoneal migratory stages of infection.This work was supported by EU grants (H2020-635408-PARAGONE) and the Spanish Ministry of Science grant AGL2015-67023-C2-1-R. The TEM studies were carried out by the Central Research Services (SCAI) of the University of CórdobaAccepted manuscriptVeterinari
The rkpU gene of Sinorhizobium fredii HH103 is required for bacterial K-antigen polysaccharide production and for efficient nodulation with soybean but not with cowpea
In this work, the role of the rkpU and rkpJ genes in the production of the K-antigen
polysaccharides (KPS) and in the symbiotic capacity of Sinorhizobium fredii HH103, a broad
host-range rhizobial strain able to nodulate soybean and many other legumes, was studied. The
rkpJ- and rkpU-encoded products are orthologous to Escherichia coli proteins involved in
capsule export. S. fredii HH103 mutant derivatives were contructed in both genes. To our
knowledge, this is the first time that the role of rkpU in KPS production has been studied in
rhizobia. Both rkpJ and rkpU mutants were unable to produce KPS. The rkpU derivative also
showed alterations in its lipopolysaccharide (LPS). Neither KPS production nor rkpJ and rkpU
expression was affected by the presence of the flavonoid genistein. Soybean (Glycine max) plants
inoculated with the S. fredii HH103 rkpU and rkpJ mutants showed reduced nodulation and clear
symptoms of nitrogen starvation. However, neither the rkpJ nor the rkpU mutants were
significantly impaired in their symbiotic interaction with cowpea (Vigna unguiculata). Thus, we
demonstrate for the first time to our knowledge the involvement of the rkpU gene in rhizobial KPS
production and also show that the symbiotic relevance of the S. fredii HH103 KPS depends on
the specific bacterium–legume interaction
Usual Dietary Intake, Nutritional Adequacy and Food Sources of Calcium, Phosphorus, Magnesium and Vitamin D of Spanish Children Aged One to <10 Years. Findings from the EsNuPI Study
Bone problems in the population begin to be establish in childhood. The present study aims to assess the usual calcium, phosphorus, magnesium, and vitamin D intakes, along with the food sources of these nutrients, in Spanish children participating in the EsNuPI (Estudio Nutricional en Población Infantil Española) study. Two 24 h dietary recalls were applied to 1448 children (1 to <10 years) divided into two sub-samples: one reference sample (RS) of the general population [n = 707] and another sample which exclusively included children consuming enriched or fortified milks, here called “adapted milks” (AMS) [n = 741]. Estimation of the usual intake shows that nutrient intake increased with age for all nutrients except vitamin D. Using as reference the Dietary Reference Values from the European Food Safety Authority (EFSA), calcium and magnesium intakes were found to be below the average requirement (AR) and adequate intake (AI), respectively, in a considerable percentage of children. Furthermore, phosphorus exceeded the AI in 100% of individuals and vitamin D was lower than the AI in almost all children studied. The results were very similar when considering only plausible reporters. When analyzing the food sources of the nutrients studied, milk and dairy products contributed the most to calcium, phosphorus, magnesium, and vitamin D. Other sources of calcium were cereals and vegetables; for phosphorus: meat, meat products, and cereals; for magnesium: cereals and fruits; and, for vitamin D: fish and eggs. These results highlight the desirability of improving the intake concerning these nutrients, which are involved in bone and metabolic health in children. The AMS group appeared to contribute better to the adequacy of those nutrients than the RS group, but both still need further improvement. Of special interest are the results of vitamin D intakes, which were significantly higher in the AMS group (although still below the AI), independent of ageThis research was funded by Instituto Puleva de Nutrición (IPN)S
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