Repeated aeolian deflation during the Allerød/GI-1a-c in the coversand lowland of NW Belgium

The results of multi-disciplinary research carried out on the deposits of the Moerbeke "Driehoek" site, located along the northern bank of the extensive Moervaart palaeolake (NW Belgium), are presented. The multi-proxy study, including sedimentological (organic matter, calcium carbonate and grain-size) and botanical (pollen, macrofossils, NPP) analyses, provided evidence of repeated aeolian deflation during the Allerod. Our results demonstrate, in combination with evidence from other soil archives within the Moervaart area, that the Allerod period in NW Europe was sedimentologically much less stable than hitherto assumed, especially during the GI-1c2 event and middle Allerod. Some of the Allerod deflation events were caused by centennial abrupt climatic oscillations, such as the short but pronounced cold GI-1c2 event, while others were likely the result of intense forest fires or a combination of both. These observations call for a revision of the existing Lateglacial litho- and chronostratigraphic schemes for the sand-belt of northern Europe

Identification of the Botanical Origin of Commercial Pine Nuts Responsible for Dysgeusia by Gas-Liquid Chromatography Analysis of Fatty Acid Profile

Over the last 10 years, complaints were increasingly reported from consumers that experienced dysgeusia following the consumption of pine nuts. In the present study, pine nuts samples (N = 16) from consumers that reported dysgeusia have been analyzed to identify the botanical origin of critical pine nuts samples. The fatty acid composition of the samples was performed, and diagnostic index values were used to identify the botanical origin of the samples. Pinus armandii nuts were identified in all the samples pure or in mixture with P. koraiensis nuts. P. armandii is not reported as edible pine nuts by the Food and Agriculture Organization (FAO). This study confirmed that consumption of P. armandii nuts may lead to dysgeusia. Based on the present study and previous work, we advise import companies to trade pine nuts from traditionally recognized species such as P. pinea, P. sibirica, P. koraiensis, or P. gerardiana

A three-thousand-year history of vegetation and human impact in Burgundy (France) reconstructed from pollen and non-pollen palynomophs analysis

International audienceThis article presents a 241 cm long sediment record documenting the vegetation history using previous termpollen and non-pollennext term palynomorphs recovered from the Fénay marsh in Burgundy (Dijon area – previous termFrance). The pollen and non-pollennext term palynomorphs (NPP) record largely reflects intensive human influence (clearing, cultivation and grazing) on the surrounding area from the Late Bronze Age and Hallstatt period. La Tène period is marked by drier conditions and a substantial increase in Alnus. During the Gallo-Roman period, high values of Alnus decrease to the benefit of Quercus. In the Early Middle Ages (5th–10th C), the swamp becomes a temporary pond and Cerealia type and Secale are cultivated in this very open landscape. During the Late Middle Ages (13th–15th C), the temporary pond is transformed into a larger and deeper pond, used by the Cistercians for hydraulic power and perhaps as a hemp-retting pit. By the end of the 16th C, the pond had dried out and was used for the cultivation of cereal

Een archeologische evaluatie en waardering van de Romeinse site Aalter Loveld (Aalter, provincie Oost-Vlaanderen).

In opdracht van de Vlaamse overheid, agentschap Onroerend Erfgoed, heeft projectbureau GATE bvba i.s.m. de U.Gent in 2013 en 2014 een bureauonderzoek en veldwerk uitgevoerd in het kader van een archeologische evaluatie en waardering van de Romeinse site Aalter-Loveld (Oost-Vlaanderen) waaruit de noodzaak tot bescherming van het gebied of een gedeelte daarvan moet blijken. Doel was door middel van inventariserend onderzoek en van diverse prospectiemethodes de begrenzing van de gekende Romeinse versterking na te gaan en tevens te bekijken hoeverre er een link kan gelegd worden met de reeds gekende nabijgelegen Romeinse nederzettingen. Op deze manier moet een evaluatie en waardering van deze site worden opgemaakt. Op basis van talloze vondsten, archeologische waarnemingen en opgravingen blijkt de site Loveld een driefasig castellum te herbergen. Het is vooral de opgraving van 2008 die harde bewijzen leverde voor die interpretatie. Dat onderzoek leverde ook de eerste indicaties op voor de afbakening van het kamp. In kader van dit onderzoek zijn al deze oude archeologische gegevens samengebracht, herbekeken en geherinterpreteerd. Samen met de geofysische onderzoeksresultaten en de boorgegevens van deze studie leverden ze verschillende scenarios op over de vorm, de grootte en de afbakening van het castellum. Zo zou het wegtracé dat werd gedetecteerd tijdens het georadaronderzoek en werd aangesneden tijdens de opgraving van 2007 gezien haar ligging en oriëntatie t.o.v. de kampgrachten mogelijk ook een oudere oorsprong kunnen hebben en misschien zelfs deel uitmaken van het castellum, van de uitbouw rondom het kamp of van de burgerlijke nederzetting die later op dezelfde locatie wordt geïnstalleerd. Dergelijk wegtracé zou op die manier verbinding kunnen gemaakt hebben met de recent onderzochte Romeinse nederzettingslocaties langs de Lostraat. Noch het geofysisch onderzoek noch de boorcampagne kon zekerheid verschaffen over de afbakening van het kamp. Ondanks de hoop om door middel van EMI-onderzoek de diepe kampgrachten duidelijk te traceren, leverde dit geen eenduidige aanwijzingen op, wat verschillende oorzaken kan hebben. De velden en weiden ten zuidwesten van het castellum werden eveneens grotendeels onderzocht in kader van het opsporen van een mogelijke link tussen het kamp en de bewoning langsheen de Lostraat. Naast het mogelijke wegtracé werden meerdere sporen waargenomen op de percelen die aansluiten bij de in 2011 opgegraven nederzettingsstructuren. Omdat geen toelating verkregen kon worden van de eigenaars zijn er geen proefputten of sleuven getrokken om bepaalde sporen te controleren of beter te duiden, wat de interpretaties van de door de overige prospectiemethodes aangereikte data aanzienlijk bemoeilijkte

Inferring site function and technological organization from combined spatial, technological and microwear-analyses at the Mesolithic wetland site of Kerkhove-Stuw, northwestern Belgium (preliminary results)

The extensive Mesolithic site of Kerkhove-Stuw was located on the top of a natural levee,adjacent to a palaeochannel of the river Scheldt. Subsequently (from the boreal onwards),the landscape was covered by approximately 4,5m to 9m of peat and alluvial clay. The infillof the palaeochannel deposits were studied by means of a high-resolution multi-proxy analysis(i.e. pollen, microcharcoal, loss on ignition, magnetic susceptibility, granulometry, molluscfauna ...etc.) to reconstruct the varying ecological settings of the prehistoric occupation.The excavations yielded thirteen spatially distinct concentrations of lithic artefacts thatcould be dated to the Early, the Middle and the Late Mesolithic, based on typology. Thiswas partly confirmed by 14C-dates on single entity charred hazelnut shells. Additionally,the site had great potential for a comprehensive technological analysis thanks to the overalllow-density of the lithic concentrations and the diversity of macroscopically discernable rawmaterial categories.Besides lithics, a considerable amount of unburnt and burnt bone fragments, and palaeob-otanical remains were documented. The preservation of a faunal assemblage (dominated byroe deer and wild boar, but also comprised of fur animals and fish remains) is exceptionalfor the Early and Middle Mesolithic in the region and will allow us, for the first time, to gaina better understanding of Mesolithic subsistence practices.Finally, to determine the inter- and intrasite functional properties and aspects of the tech-nological organization of the thirteen lithic concentrations, the spatial distribution of thedifferent types of material remains are studied, combined with a technological and microwearanalysis of the lithic artefacts. For example, the location of ten possible surface hearths couldbe derived from heavily burnt lithic artefacts and burnt organic remains. So far, preliminary results from the technological analysis indicate the presence of several expedient technolo-gies, more elaborate opposed striking platform knapping sequences and a possible diachronicevolution in preferential raw material use. Both spatial analyses and lithic technology arereinforced by an extensive microwear analysis that can specify the objectives of the knappingsequences and mostly the spatial organization of the different activities (butchery, hide andplant scraping, osseous tools manufacturing...) for each occupation phase.In the future, the results from Kerkhove will have to be compared with those previouslyobtained with the same protocol from other (dryland) sites in northwestern Belgium

Middelkerke Kalkaert Rapportage van het archeologisch proefsleuvenonderzoek - 2 november tot 6 december 2011

Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]

Rheophysics of dense granular materials : Discrete simulation of plane shear flows

We study the steady plane shear flow of a dense assembly of frictional, inelastic disks using discrete simulation and prescribing the pressure and the shear rate. We show that, in the limit of rigid grains, the shear state is determined by a single dimensionless number, called inertial number I, which describes the ratio of inertial to pressure forces. Small values of I correspond to the quasi-static regime of soil mechanics, while large values of I correspond to the collisional regime of the kinetic theory. Those shear states are homogeneous, and become intermittent in the quasi-static regime. When I increases in the intermediate regime, we measure an approximately linear decrease of the solid fraction from the maximum packing value, and an approximately linear increase of the effective friction coefficient from the static internal friction value. From those dilatancy and friction laws, we deduce the constitutive law for dense granular flows, with a plastic Coulomb term and a viscous Bagnold term. We also show that the relative velocity fluctuations follow a scaling law as a function of I. The mechanical characteristics of the grains (restitution, friction and elasticity) have a very small influence in this intermediate regime. Then, we explain how the friction law is related to the angular distribution of contact forces, and why the local frictional forces have a small contribution to the macroscopic friction. At the end, as an example of heterogeneous stress distribution, we describe the shear localization when gravity is added.Comment: 24 pages, 19 figure

Chemical treatment of the intra-canal dentin surface: a new approach to modify dentin hydrophobicity

Objective This study evaluated the hydrophobicity of dentin surfaces that were modified through chemical silanization with octadecyltrichlorosilane (OTS). Material and Methods An in vitro experimental study was performed using 40 human permanent incisors that were divided into the following two groups: non-silanized and silanized. The specimens were pretreated and chemically modified with OTS. After the chemical modification, the dentin hydrophobicity was examined using a water contact angle measurement (WCA). The effectiveness of the modification of hydrophobicity was verified by the fluid permeability test (FPT). Results and Conclusions Statistically significant differences were found in the values of WCA and FPT between the two groups. After silanization, the hydrophobic intraradicular dentin surface exhibited in vitro properties that limit fluid penetration into the sealed root canal. This chemical treatment is a new approach for improving the sealing of the root canal system

Rapportage van een archeologisch boor- en proefsleuvenonderzoek (25/09 - 8/10/2013)

Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]

Differential effect of maternal diet supplementation with α-Linolenic adcid or n-3 long-chain polyunsaturated fatty acids on glial cell phosphatidylethanolamine and phosphatidylserine fatty acid profile in neonate rat brains

<p>Abstract</p> <p>Background</p> <p>Dietary long-chain polyunsaturated fatty acids (LC-PUFA) are of crucial importance for the development of neural tissues. The aim of this study was to evaluate the impact of a dietary supplementation in n-3 fatty acids in female rats during gestation and lactation on fatty acid pattern in brain glial cells phosphatidylethanolamine (PE) and phosphatidylserine (PS) in the neonates.</p> <p>Methods</p> <p>Sprague-Dawley rats were fed during the whole gestation and lactation period with a diet containing either docosahexaenoic acid (DHA, 0.55%) and eicosapentaenoic acid (EPA, 0.75% of total fatty acids) or α-linolenic acid (ALA, 2.90%). At two weeks of age, gastric content and brain glial cell PE and PS of rat neonates were analyzed for their fatty acid and dimethylacetal (DMA) profile. Data were analyzed by bivariate and multivariate statistics.</p> <p>Results</p> <p>In the neonates from the group fed with n-3 LC-PUFA, the DHA level in gastric content (+65%, P < 0.0001) and brain glial cell PE (+18%, P = 0.0001) and PS (+15%, P = 0.0009) were significantly increased compared to the ALA group. The filtered correlation analysis (P < 0.05) underlined that levels of dihomo-γ-linolenic acid (DGLA), DHA and n-3 docosapentaenoic acid (DPA) were negatively correlated with arachidonic acid (ARA) and n-6 DPA in PE of brain glial cells. No significant correlation between n-3 and n-6 LC-PUFA were found in the PS dataset. DMA level in PE was negatively correlated with n-6 DPA. DMA were found to occur in brain glial cell PS fraction; in this class DMA level was correlated negatively with DHA and positively with ARA.</p> <p>Conclusion</p> <p>The present study confirms that early supplementation of maternal diet with n-3 fatty acids supplied as LC-PUFA is more efficient in increasing n-3 in brain glial cell PE and PS in the neonate than ALA. Negative correlation between n-6 DPA, a conventional marker of DHA deficiency, and DMA in PE suggests n-6 DPA that potentially be considered as a marker of tissue ethanolamine plasmalogen status. The combination of multivariate and bivariate statistics allowed to underline that the accretion pattern of n-3 LC-PUFA in PE and PS differ.</p