283 research outputs found

    Agelastatin A, a new skeleton cytotoxic alkaloid of the oroidin family : isolation from the Axinellid sponge Agelas dendromorpha of the Coral Sea

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    Agelastatin A, isolated from the axinellid sponge #Agelas dendromorpha$ of the Coral Sea, is a new skeleton alkaloid with, unusually for the oroidin family to which it belongs, marked cytototoxicity toward tumour cells in culture. (Résumé d'auteur

    L’apport de l’analyse morphologique, microscopique et chimique des scories en forme de culot Ă  la restitution des activitĂ©s de forge

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    Si les diffĂ©rents travaux rĂ©alisĂ©s dans une forge sont assez bien connus, il est difficile de les retrouver au travers de l’analyse des seuls dĂ©chets. Ce sont pourtant ceux-ci que l’on retrouve presque exclusivement sur les ateliers dĂ©gagĂ©s au cours de fouilles archĂ©ologiques. Pour en extraire un maximum de renseignements, il est nĂ©cessaire de mettre en place une mĂ©thodologie rigoureuse d’étude, depuis l’échantillonnage sur le terrain jusqu’aux analyses chimiques en laboratoire. Les notions de quantification et de reprĂ©sentativitĂ© sont extrĂȘmement importantes pour tenter de qualifier et quantifier les travaux effectuĂ©s par le forgeron, pour dĂ©terminer la nature des matĂ©riaux employĂ©s et pour tenter d’estimer une quantitĂ© minimale de fer travaillĂ©. L’étude, bien que ciblĂ©e sur les scories en culot, montre que l’ensemble des dĂ©chets produits dans un atelier doit ĂȘtre pris en considĂ©ration lors des Ă©tudes palĂ©omĂ©tallurgiques si l’on veut rĂ©ellement apprĂ©hender l’atelier. L’exemple du site du Puy-de-GrĂące (La TĂšne finale) permet de documenter les apports de cette mĂ©thodologie.If the different works produced in a smithing workshop are well known, it is difficult to identify them only from the analyses from the wastes. However, these wastes are generally the only remnants that can be found during excavation of archaeological ironworkshops. To obtain the maximum of informations of these wastes, it is necessary to propose a rigorous methodology, from the sampling in the archaeological site to chemical analyses in laboratory. The quantification and representativeness notions are very important to qualify and quantify the works operated by the blacksmith, to determine the nature of used materials and to estimate the minimal quantity of worked iron. This study, although targeted on the tape slags, shows that it is necessary to take into account the totality of the wastes found in the archaeological smithy during the archeaometallurgical studies for a good comprehension of this smithy functioning. The Puy-de-GrĂące example (France) allows documenting the contribution of this methodology

    Current status and perspectives of the official sensory control methods in protected designation of origin food products and wines

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    Resultado de un trabajo colaborativo dentro del Working Group PDO de la European Sensory Science SocietyProtected Designation of Origin (PDO) is part of the regulated quality schemes in the European Union (EU). Producers of PDO food products and wines have to present EU authorities a technical specification of their product, which includes its sensory description. European regulation 1151/12 establishes that sensory characteristics included in PDO certification must be guaranteed. Nevertheless, there is no standardized approach for the development of sensory control methods for PDO food products, so each entity in charge of controlling the characteristics of the PDO products decides the best way to follow this legal requirement. This paper presents the current situation in Spain, Italy and France in relation to the official sensory control of PDO food products and wines and the accreditation of the laboratories for this control (these three countries represent 68.9% of the total PDO products registered in the EU). This manuscript also shows the main methodologies applied in the official sensory control of PDO food products and wines. The wide diversity of methods used for the sensory control and associated panel management among PDOs manifests the need to harmonize technical criteria and references at European level. This is also urgent, because broad differences in the approaches and requirements for sensory control could bring about unfair competition among PDOs. In this sense, European Sensory Science Society (E3S) has become an EA recognized stakeholder collaborating in a framework in order to prepare a document for the harmonization of methodological approaches and technical criteria for the sensory control of PDO food products and wines

    Nouvelles donnĂ©es sur l’importance des vestiges de sidĂ©rurgie ancienne en Puisaye

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    Des prospections pĂ©destres, conduites depuis une dizaine d’annĂ©es dans la rĂ©gion naturelle de la Puisaye, dans le sud-ouest du dĂ©partement de l’Yonne (France, Bourgogne), ont entraĂźnĂ© l’identification et la localisation de prĂšs de 2500 amas et aires de concentrations de dĂ©chets sidĂ©rurgiques anciens relevant du procĂ©dĂ© de production du fer en bas fourneau par la mĂ©thode directe. Trois datations 14C rĂ©alisĂ©es sur des charbons prĂ©levĂ©s dans les amas et dans les scories confirment l’existence d’ateliers de la pĂ©riode gallo-romaine, associĂ©s Ă  des amas de volume considĂ©rable tĂ©moignant d’une grosse production de fer et Ă  des dĂ©chets scorifiĂ©s fortement vitreux contenant des billes de fer.Searches conducted on foot over the last ten years or so in the Puisaye, in the south-west of the department of the Yonne (Burgundy), have resulted in the identification and localisation of approximately 2500 piles and areas of ancient iron-working scrap. These are the remains of bloomeries that used the direct method for iron production. Carbon-dating on three pieces of coal taken from the piles and the slag confirm the existence of iron-making workshops during the Gallo-Roman period. Large piles of highly vitreous slag containing iron-ore pellets attest extensive iron production.Seit ungefĂ€hr 10 Jahren werden in der Puisaye, im SĂŒdwesten des Departements Yonne (Frankreich, Region Bourgogne) Feldbegehungen durchgefĂŒhrt. Sie haben zur Identifizierung und Lokalisierung von fast 2500 Schlackenhalden und –Konzentrationen von EisenverhĂŒttungsabfĂ€llen gefĂŒhrt, die bei der Gewinnung von Eisen in Rennöfen durch die direkte Reduktionsmethode angefallen waren. Drei 14C-Datierungen von Kohleresten aus den Halden und Schlacken bestĂ€tigen die Existenz von WerkstĂ€tten in gallo-römischer Zeit. Große Schlackenhalden und stark glasige verschlackte AbfĂ€lle mit Eisenperlen zeugen vom Umfang der Eisenproduktion

    Continental break-up history of a deep magma-poor margin based on seismic reflection data (northeastern Gulf of Aden margin, offshore Oman)

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    International audienceRifting between Arabia and Somalia started around 35 Ma followed by spreading at 17.6 Ma in the eastern part of the Gulf of Aden. The first-order segment between Alula-Fartak and Socotra-Hadbeen fracture zones is divided into three second-order segments with different structure and morphology. Seismic reflection data were collected during the Encens Cruise in 2006 on the northeastern margin. In this study, we present the results of Pre-Stack Depth Migration of the multichannel seismic data from the western segment, which allows us to propose a tectono-stratigraphic model of the evolution of this segment of the margin from rifting to the present day. The chronological interpretation of the sedimentary sequences is mapped out within relation to the onshore observations and existing dating. After a major development of syn-rift grabens and horsts, the deformation localized where the crust is the thinnest. This deformation occurred in the distal margin graben (DIM) at the northern boundary of the ocean-continent transition (OCT) represented by the OCT ridge. At the onset of the OCT formation differential uplift induced a submarine landslide on top of the deepest tilted block and the crustal deformation was restricted to the southern part of the DIM graben, where the continental break-up finally occurred. Initial seafloor spreading was followed by post-rift magmatic events (flows, sills and volcano-sedimentary wedge), whose timing is constrained by the analysis of the sedimentary cover of the OCT ridge, correlated with onshore stratigraphy. The OCT ridge may represent exhumed serpentinized mantle intruded by post-rift magmatic material, which modified the OCT after its emplacement

    Is the typicality of “Provence RosĂ© wines” only a matter of color?

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    Aims: Given the diversity of French dry RosĂ© wines, Provence RosĂ© producers (France) wish to evaluate the typicality of their wines in order to better identify their typical characteristics. A clear pink color is one of them but they would also like to identify some specific odors and aromas. Here, we address these issues by: (i) assessing whether the identity of Provence RosĂ© wines is perceptible by tasting and shared by professionals based on specific odors and aromas (disregarding color as indicator using black glasses), and (ii) evaluating the impact of color on Provence RosĂ© wine typicality. Methods and results: Complementary methods were used: exemplarity measurements by a panel of wine professionals, sensory evaluation by a trained expert panel, and color assessment. It was confirmed that Provence RosĂ© wine typicality is based on color because the clearest wines were found to be more typical. However, typicality in odors and aromas was also demonstrated. Using black glasses, wine professionals from Provence agreed on ‘citrus fruit’, ‘exotic fruit’ and ‘fresh floral’ odors and aromas being typical attributes of Provence RosĂ© wines. Next, when using transparent glasses, the color of the wines clearly modified the perception of exemplarity. Conclusion: There is no single sensory profile of typical Provence RosĂ© wines. Variability within the sensory profiles of this specific RosĂ© wine area was observed, but some common aromatic and visual characteristics were identified. Significance and impact of the study: These results could be used as a marketing tool to better highlight the specific intrinsic characteristics of Provence RosĂ© wines. It will now be interesting to investigate the Provence area further in order to evaluate potential sub-area specificities linked to “terroir” factors

    Deformation bands and alteration in porous glass-rich volcaniclastics: Insights from Milos, Greece

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    Deformation bands in porous volcaniclastics are little studied structural heterogeneities despite their relevance for constraining the modalities of deformation development and related fluid-rock interactions in volcanic areas. We document a dense network of normal-sense Deformation Bands (Normal-sense Compactional Shear Bands (NCSBs) affecting upper Pliocene felsic glassy tuffites in Milos, Greece. NCSBs probably formed between 300 and 500 m of burial depth, in response to NE-SW directed extension which is related to volcanic rift development in the area. They accommodate mm-to m-shear-offsets, trend either N105 ± 10° or N070 ± 10°, and show mutual cross-cutting relations. The NCSB fault rock is made of ultracataclasite in which the cataclastic mechanisms have affected both the mineral fraction and the volcanic glass. Minerals are fractured along their cleavages whereas pumices are interestingly fractured along their vesicles. The development of chemical alteration (dissolution and cementation) essentially into the ultracataclasite is expressed through glass-hosted corrosion gulfs and smectites filling the intergranular porosity. These observations support that NCSBs preferentially retained water, have been the seat of greater fluid flow, and are the locus of ongoing phyllosilicate self-sealing in the vadose zone. A significant decrease (up to one order of magnitude) in porosity is measured within the studied NCSBs

    Integrin Alpha 8 Recessive Mutations Are Responsible for Bilateral Renal Agenesis in Humans

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    Renal hypodysplasia (RHD) is a heterogeneous condition encompassing a spectrum of kidney development defects including renal agenesis, hypoplasia, and (cystic) dysplasia. Heterozygous mutations of several genes have been identified as genetic causes of RHD with various severity. However, these genes and mutations are not associated with bilateral renal agenesis, except for RET mutations, which could be involved in a few cases. The pathophysiological mechanisms leading to total absence of kidney development thus remain largely elusive. By using a whole-exome sequencing approach in families with several fetuses with bilateral renal agenesis, we identified recessive mutations in the integrin α8-encoding gene ITGA8 in two families. Itga8 homozygous knockout in mice is known to result in absence of kidney development. We provide evidence of a damaging effect of the human ITGA8 mutations. These results demonstrate that mutations of ITGA8 are a genetic cause of bilateral renal agenesis and that, at least in some cases, bilateral renal agenesis is an autosomal-recessive disease
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