La dynamique du changement : paysage économique de l'établissement rural islandais depuis le Landnam (IXe au XIXe siècle)

L’Islande, pivot de l’Atlantique Nord, est une terre de contrastes, autant du point de vue du paysage et que de son histoire. Dans les siècles suivants le Landnám, le territoire a subi les effets des changements climatiques, d’une part, mais aussi de l’anthropisation. Contrairement à leurs contemporains Groenlandais, et malgré des abandons locaux et plusieurs transformations, les établissements ruraux islandais ont persisté, ce qui est sans doute le témoin le plus éloquent de leur résilience. La recherche archéologique sur les établissements norrois de l’Atlantique Nord a permis de soulever plusieurs problématiques concernant les relations Homme-environnement et, plus spécifiquement, sur leur succès en Islande. Cet axe de recherche a ciblé l’identification et la caractérisation des facteurs impliqués dans le succès ou l’échec des économies agropastorales marginales. Dans cette perspective, plus de deux décennies de recherches ont visé l’étude du passé matériel des Islandais et la reconstruction des paysages. De manière générale, elles ont permis de mettre en lumière l’existence de périodes d’occupation et d’abandon des établissements lesquels ont pu être retracés temporellement et spatialement à travers le pays. Ces périodes paraissent coïncider, sans toutefois s’y restreindre, avec des événements climatiques et historiques, bien que la dynamique dans laquelle elles s’inscrivent demeure partiellement comprise. Cette thèse explore cette dynamique à l’intérieur du cadre théorique de l’Écologie historique et à travers l’axe du paysage économique, qui comprend les concepts tels la paléoéconomie, le paysage et les schèmes d’établissement. Ces concepts ont été appliqués à des données archéologiques recueillies dans le domaine de Svalbarđ dans le nord-est de l’Islande : une région relativement marginale en comparaison au reste du pays. Les assemblages fauniques ont été analysés dans l’optique de cibler les changements dans les pratiques d’élevage et d’exploitation des ressources sauvages pour deux sites historiquement liés, soit Svalbarđ et Hjálmarvík, et occupés du Xe siècle à aujourd’hui pour la première, et jusqu’au XIXe siècle pour la seconde. L’analyse des assemblages a mené à la reconstitution complète du paysage économique de Hjálmarvík, à l’exploration du dialogue économique complexe entre les deux établissements et leurs contemporaines. Cette thèse révèle comment ces deux établissements sont économiquement liés et à quel point ce lien a eu un impact sur leur pérennité.Iceland, the pivot point of the North Atlantic, is a land of many contrasts, both in landscape and history. In the centuries following Landnám, the country was impacted by a series of climatic changes and anthropogenic impacts. In contrast to the history of its Greenlandic homologues, and despite local abandonments and transformations, rural settlements in Iceland endured into the modern era: the most eloquent demonstration of their resilience. Archaeological research on the Norse North Atlantic settlements has raised many questions concerning humanenvironment interactions and especially regarding the successful aspects of those interactions. A focal point of this research has been the identification of factors involved in the success or failure of seemingly marginal agropastoral economies. To this end, more than a generation of archaeological research has sought to study Iceland’s material past and reconstruct its landscape history. In general, this work has demonstrated that Iceland has seen many periods of settlement and abandonment which can be traced temporally and spatially throughout the country. Those periods appear to coincide, variously, with historical as well as environmental events, but the dynamic of environmental and historical factors involved in each remains only partially understood. This thesis explores this topic through the theoretical framework of Historical Ecology and through the perspective of economic landscape, which combines palaeoeconomy, landscape and settlement patterns. These concepts are applied to archaeological data gathered in Svalbarðhreppur, northeast Iceland: a region located on the historical peripheries of Iceland’s agricultural economy and one that is in several respects marginal in terms of economic potential. Zooarchaeological collections were analysed in order to define changes in livestock herding and wild resource harvesting at the farm of Hjálmarvík from the 10th to 19th century AD and lead to a complete reconstruction of Hjálmarvík’s economic landscape in the context of regional patterns of settlement and abandonment and in reference to Hjálmarvík’s complex relationship to the estate farm of Svalbarð. This research reveals contrasting trajectories of livestock herding and wild animal harvesting at Hjálmarvík. While the former remained remarkably stable over time, the latter were critical subsistence resources until the 14th century, whereupon they declined into a complimentary role. At the same time, fish and seals began to take a primary economic role at the manor farm of Svalbarð. This study suggests that while sheep herding for daily and market production integrated the local community, shore edge grazing and wild mammal species obtained at Hjálmarvík were fundamental to its resilience

Contexte économique de la ferme islandaise prémoderne (16ème-20ème siècles) des Vestfirðir : une analyse zooarchéologique à la recherche de marqueurs de stress

L'époque prémoderne islandaise (16eme au 19eme siècle) a longtemps été perçue par les historiens et les archéologues comme une période sombre de l'histoire du pays. Les éruptions volcaniques, les épisodes de famine, la variabilité climatique et la situation politique sont des événements qui ont inévitablement affecté la population et la mémoire collective. Toutefois, comment cela se traduit-il pour l'archéologue qui doit interpréter, d'une part, les traces laissées par la population et, d'autre part, la mesure dans laquelle ces événements l'ont affectée? Afin de répondre à cette interrogation, deux assemblages fauniques issus de sites archéologiques de la péninsule des Vestfirðir, Eyri et Vatnsfjörður, ont fait l'objet d'une analyse zooarchéologique. La méthodologie appliquée à cette recherche réussit à faire la démonstration de l'existence de pressions économiques et démographiques durant la période prémoderne et les résultats démontrent la nécessité de reconsidérer certains concepts relatifs au stress et aux établissements côtiers islandais

In Subfertile Couple, Abdominal Fat Loss in Men Is Associated with Improvement of Sperm Quality and Pregnancy: A Case-Series

International audienceBackground: The impact of overweight among men of reproductive-age may affect fertility. Abdominal fat, more than body mass index, is an indicator of higher metabolic risk, which seems to be involved in decreasing sperm quality. This study aims to assess the relationship between abdominal fat and sperm DNA fragmentation and the effect of abdominal fat loss, among 6 men in subfertile couples. Methods: Sperm DNA fragmentation, abdominal fat and metabolic and hormonal profiles were measured in the 6 men before and after dietary advices. Seminal oxidative stress and antioxidant markers were determined. Results: After several months of a lifestyle program, all 6 men lost abdominal fat (patient 1: loss of 3 points of abdominal fat, patient 2: loss of 3 points, patient 3: loss of 2 points, patient 4: loss of 1 point, patient 5: loss of 4 points and patient 6: loss of 13 points). At the same time, their rate of sperm DNA fragmentation decreased: 9.5% vs 31%, 24% vs 43%, 18% vs 47%, 26.3% vs 66%, 25.4% vs 35% and 1.7% vs 25%. Also, an improvement in both metabolic (significant decrease in triglycerides and total cholesterol; p = 0.0139) and hormonal (significant increase in testosterone/oestradiol ratio; p = 0.0139) blood profiles was observed after following the lifestyle program. In seminal plasma, the amount of SOD2 has significantly increased (p = 0.0139) while in parallel carbonylated proteins have decreased. Furthermore, all spouses got pregnant. All pregnancies were brought to term. Conclusion: This study shows specifically that sperm DNA fragmentation among men in subfertile couples could be affected by abdominal fat, but improvement of lifestyle factor may correct this alteration. The effect of specific abdominal fat loss on sperm quality needs further investigation. The reduction of oxidative stress may be a contributing factor

SUITABILITY OF WOOD CHIPS FROM FORESTRY AND DIFFERENT BIOMASS FEEDSTOCKS FOR USE IN A SEMI-INDUSTRIAL PLANT OF BTL PRODUCTION BY GASIFICATION

A semi-industrial plant of BtL production by biomass gasification is planned to be operating in 2011 in the Northern-East of France by a French Energy Research Centre, called Commissariat à l’Energie Atomique (CEA), and several partners. This demonstration plant will be a 50 MW plant, based on an entrained flow reactor, followed by different stages of syngas cleaning and a final stage of Fischer-Tropsch synthesis. One study has been launched on the biomass regional resources that may be used as feedstock in the plant. The first task of this study deals with the availability of the resources and their feasibility and cost of supply. This paper is focused on the second task, whose aim is to check the suitability of the potential resources with the process, in order to define which one should be chosen. A sampling based on several tens samples from the region was first used, both from wood chips from forestry, wood chips from Short Rotation Coppice (SRC) and agricultural raw materials including straw and energy crops. Measurements were done on the main influential properties of biomass, either physical (granulometry, density, moisture), thermal (LHV) or physico-chemical (proximate analysis, elemental composition, particularly in minor elements, ash composition and fusibility). Results show that there is not much variability in the biomass properties inside the different families (wood chips, agricultural raw materials). The values of most properties fall in the range of the required specifications. However, some properties may be questionable: (i) wood chips granulometry, with too many fine particles (ii) density, which is too low in agricultural products (0.05), (iii) sulphur, fluorine and chlorine contents, which are too high, especially chlorine in agricultural residues (1000-8000 ppm) (iv) other impurities amounts, such as Cr, Cu, Zn, Ni, that are above specifications in some samples (v) ash content, which is slightly too high in SRC (3 wmf%) and too high in most agricultural raw materials (5 wmf%) (vi) ash melting point - whose measurement still needs to be confirmed - but which is apparently too low in most agricultural samples and in some SRC. Based on these statements, wood chips from forestry appear as the most suitable resource for the process. SRC also seem quite suitable for the process and may be seen as a short-term alternative. Agricultural raw materials are more problematical and may be seen as a short to mid-term option. Therefore, wood chips will be the first resource to be used in the demonstration plant and a complimentary sampling has been recently performed on this kind of feedstock, leading to the adjunction of 60 new samples. These measurements should enable to define more precisely the range of variation of the problematic properties

Complex nature of apparently balanced chromosomal rearrangements in patients with autism spectrum disorder

Background: Apparently balanced chromosomal rearrangements can be associated with an abnormal phenotype, including intellectual disability and autism spectrum disorder (ASD). Genome-wide microarrays reveal cryptic genomic imbalances, related or not to the breakpoints, in 25% to 50% of patients with an abnormal phenotype carrying a microscopically balanced chromosomal rearrangement. Here we performed microarray analysis of 18 patients with ASD carrying balanced chromosomal abnormalities to identify submicroscopic imbalances implicated in abnormal neurodevelopment. Methods: Eighteen patients with ASD carrying apparently balanced chromosomal abnormalities were screened using single nucleotide polymorphism (SNP) arrays. Nine rearrangements were de novo, seven inherited, and two of unknown inheritance. Genomic imbalances were confirmed by fluorescence in situ hybridization and quantitative PCR. Results: We detected clinically significant de novo copy number variants in four patients (22%), including three with de novo rearrangements and one with an inherited abnormality. The sizes ranged from 3.3 to 4.9 Mb; three were related to the breakpoint regions and one occurred elsewhere. We report a patient with a duplication of the Wolf-Hirschhorn syndrome critical region, contributing to the delineation of this rare genomic disorder. The patient has a chromosome 4p inverted duplication deletion, with a 0.5 Mb deletion of terminal 4p and a 4.2 Mb duplication of 4p16.2p16.3. The other cases included an apparently balanced de novo translocation t(5;18)(q12;p11.2) with a 4.2 Mb deletion at the 18p breakpoint, a subject with de novo pericentric inversion inv(11)(p14q23.2) in whom the array revealed a de novo 4.9 Mb deletion in 7q21.3q22.1, and a patient with a maternal inv(2)(q14.2q37.3) with a de novo 3.3 Mb terminal 2q deletion and a 4.2 Mb duplication at the proximal breakpoint. In addition, we identified a rare de novo deletion of unknown significance on a chromosome unrelated to the initial rearrangement, disrupting a single gene, RFX3. Conclusions: These findings underscore the utility of SNP arrays for investigating apparently balanced chromosomal abnormalities in subjects with ASD or related neurodevelopmental disorders in both clinical and research settings

Bibliothèques d’enfer(s) : interdits, contraintes et libertés en bibliothèque

Journée thématique organisée à l\u27enssib par les élèves conservateurs promus DCB 21. La bibliothèque, espace de formation et de culture, est aussi un lieu où circulent un certain nombre d’interdits : censure, usages prohibés, restriction de certains accès. Quel rôle le bibliothécaire joue-t-il alors dans cet espace qu’il entend souvent contrôler ? Quelles formes de censure peut-il subir ou parfois faire subir ? Quels remèdes y apporter ? L’objet de cette journée fut d’interroger les pratiques afin de mieux cerner la frontière à la fois floue et fragile entre interdits et limites et de déterminer en quoi la bibliothèque peut aujourd’hui être un espace de contraintes ou de libertés

iNKT cell development is orchestrated by different branches of TGF-β signaling

Invariant natural killer T (iNKT) cells constitute a distinct subset of T lymphocytes exhibiting important immune-regulatory functions. Although various steps of their differentiation have been well characterized, the factors controlling their development remain poorly documented. Here, we show that TGF-β controls the differentiation program of iNKT cells. We demonstrate that TGF-β signaling carefully and specifically orchestrates several steps of iNKT cell development. In vivo, this multifaceted role of TGF-β involves the concerted action of different pathways of TGF-β signaling. Whereas the Tif-1γ branch controls lineage expansion, the Smad4 branch maintains the maturation stage that is initially repressed by a Tif-1γ/Smad4-independent branch. Thus, these three different branches of TGF-β signaling function in concert as complementary effectors, allowing TGF-β to fine tune the iNKT cell differentiation program