Domain wall structure in magnetic bilayers with perpendicular anisotropy

We study the magnetic domain wall structure in magnetic bilayers (two ultrathin ferromagnetic layers separated by a non magnetic spacer) with perpendicular magnetization. Combining magnetic force and ballistic electron emission microscopies, we are able to reveal the details of the magnetic structure of the wall with a high spatial accuracy. In these layers, we show that the classical Bloch wall observed in single layers transforms into superposed N\'eel walls due to the magnetic coupling between the ferromagnetic layers. Quantitative agreement with micromagnetic calculations is achieved.Comment: Author adresses AB, SR, JM and AT: Laboratoire de Physique des Solides, CNRS, Universit\'e Paris Sud, UMR 8502, 91405 Orsay Cedex, France ML : Laboratoire PMTM, Institut Galil\'ee, CNRS, Universit\'e Paris-13, UPR 9001, 93430 Villetaneuse, Franc

Structure and diversity of shallow soft-bottom benthic macrofauna in the Gulf of Lions (NW Mediterranean).

14 páginas, 10 figuras, 4 tablas.Samples of soft-sediment macrobenthos from 92 sites between 10 and 50 m depth were used to assess (1) the main soft-bottom macrofauna communities in the Gulf of Lions, (2) the different components of the diversity of benthic macrofauna in this area, and (3) the relevance of the use of major taxonomic groups as surrogates for the analysis of the structure and diversity of total macrofauna. Three main communities were identified by cluster analysis and associated procedures. These communities corresponded well to the assemblages recently identified on the basis of polychaete composition. The a-diversity indices were in accordance with those reported for similar communities in the Mediterranean. Conversely, the b-diversity value was higher than the few other data available in the literature for marine soft-bottom macrofauna. The total number of species in the studied area estimated by the ‘‘total species accumulation curve’’ (TS) method was 2,319, which was only 10% higher than the number obtained by extrapolation of the species–area curve. The similarity matrix based on polychaetes correlated best with the one based on total macrofauna. Polychaetes and crustaceans were also the best surrogates of total macrofauna when assessing a-diversity (except in the case of D*). Conversely, molluscs were the best surrogates of total macrofauna b-diversity. Our results show that the choice of an optimal surrogate for total benthic macrofauna depends on the characteristic of the benthic macrofauna to be studied. Moreover, this choice is also dependent on the environment to be studiedThis work is part of the PhD thesis of Ce´line Labrune. It was carried out within the EC Network of Excellence MARBEF. Ce´line Labrune was supported by the SYSCOLAG project run by the Re´gion Languedoc-Roussillon.Peer reviewe

Role of environmental factors for the vertical distribution (0–1000 m) of marine bacterial communities in the NW Mediterranean Sea

Bacterioplankton plays a central role in energy and matter fluxes in the sea, yet the factors that constrain its variation in marine systems are still poorly understood. Here we use the explanatory power of direct multivariate gradient analysis to evaluate the driving forces exerted by environmental parameters on bacterial community distribution in the water column. We gathered and analysed data from a one month sampling period from the surface to 1000 m depth at the JGOFS-DYFAMED station (NW Mediterranean Sea). This station is characterized by very poor horizontal advection currents which makes it an ideal model to test hypotheses on the causes of vertical stratification of bacterial communities. Capillary electrophoresis single strand conformation polymorphism (CE-SSCP) fingerprinting profiles analyzed using multivariate statistical methods demonstrated a vertical zonation of bacterial assemblages in three layers, above, in or just below the chlorophyll maximum and deeper, that remained stable during the entire sampling period. Through the use of direct gradient multivariate ordination analyses we demonstrate that a complex array of biogeochemical parameters is the driving force behind bacterial community structure shifts in the water column. Physico-chemical parameters such as phosphate, nitrate, salinity and to a lesser extent temperature, oxygen, dissolved organic carbon and photosynthetically active radiation acted in synergy to explain bacterial assemblages changes with depth. Analysis of lipid biomarkers of organic matter sources and fates suggested that bacterial community structure in the surface layers was in part explained by lipids of chloroplast origin. Further detailed analysis of pigment-based phytoplankton diversity gave evidence of a compartmentalized influence of several phytoplankton groups on bacterial community structure in the first 150 m depth

Transitions dipolaires induites par collisions sur un faisceau de formaldéhyde. Effet d'un champ électrique

Using a H2CO molecular beam, a method is first described which permits the observation of rotational transitions ΔJ = ± n (n ≽ 1), induced by collisions with the molecules of a target gas. In the case H2CO → H 2CO, selection rules are defined and rotational resonance effects are observed on the differential cross sections for some ΔJ = — 1 transitions. It appears that a direct electric field E considerably modifies the H2CO cross sections σJ. Using the pair H 2CO → NH3, the study of σJ variations with E shows that the ΔJ = 0 transitions become forbidden, when E is intense. The experimental results are compared with the theoretical transition probabilities variations, due to E and calculated in the Born approximation. An experimental method is deduced which permits, by application of an electric field, to select AJ = 0 transitions on a molecular beam.Nous présentons d'abord une méthode expérimentale qui permet d'observer les transitions rotationnelles ΔJ = ± n (n ≽ 1) induites par collisions entre les molécules d'un faisceau de formaldéhyde et un gaz tampon. En prenant H2CO comme gaz tampon, nous précisons les règles de sélection et, sur les sections de collisions correspondant à plusieurs transitions ΔJ = — 1, nous mettons en évidence des effets de résonance rotationnelle. Nous constatons qu'un champ électrique continu modifie considérablement les sections de collisions du formaldéhyde. Sur le système dipolaire H2 CO-NH3, l'étude des variations caractéristiques de celles-ci en fonction du champ appliqué montre que les transitions ΔJ. = 0 de H2CO deviennent interdites en champ fort. Nous comparons les résultats expérimentaux aux variations de probabilité de transition dues au champ électrique et calculées dans l'approximation de Born. On déduit une méthode expérimentale permettant de trier par effet de champ les transitions ΔJ = 0 sur le faisceau moléculaire

Glycogen Storage Disease Type Ia:Current Management Options, Burden and Unmet Needs

Glycogen storage disease type Ia (GSDIa) is caused by defective glucose-6-phosphatase, a key enzyme in carbohydrate metabolism. Affected individuals cannot release glucose during fasting and accumulate excess glycogen and fat in the liver and kidney, putting them at risk of severe hypoglycaemia and secondary metabolic perturbations. Good glycaemic/metabolic control through strict dietary treatment and regular doses of uncooked cornstarch (UCCS) is essential for preventing hypoglycaemia and long-term complications. Dietary treatment has improved the prognosis for patients with GSDIa; however, the disease itself, its management and monitoring have significant physical, psychological and psychosocial burden on individuals and parents/caregivers. Hypoglycaemia risk persists if a single dose of UCCS is delayed/missed or in cases of gastrointestinal intolerance. UCCS therapy is imprecise, does not treat the cause of disease, may trigger secondary metabolic manifestations and may not prevent long-term complications. We review the importance of and challenges associated with achieving good glycaemic/metabolic control in individuals with GSDIa and how this should be balanced with age-specific psychosocial development towards independence, management of anxiety and preservation of quality of life (QoL). The unmet need for treatment strategies that address the cause of disease, restore glucose homeostasis, reduce the risk of hypoglycaemia/secondary metabolic perturbations and improve QoL is also discussed.</p

Long-term (1998–2010) large-scale comparison of the ecological quality status of gulf of lions (NW Mediterranean) benthic habitats

12 páginas, 4 tablas, 8 figuras.A comprehensive Mediterranean data set has been used to address 3 questions associated with the use of sensitivity/tolerance based biotic indices to infer the Ecological Quality status (EcoQs) of benthic habitats. Our results showed: (1) a significant effect of the reference database on derived sensitivity/tolerance measure (ES500.05) as well as associated Benthic Quality Index values and derived EcoQs; (2) a lack of correlation neither between BQI and AZTI Marine Biotic Index values nor between BQI and Multivariate-AZTI Marine Biotic Index values; (3) a lack of correlation between the values of the Benthic Habitat Quality Index (index derived from Sediment Profile Imagery) and those of either of the 3 tested biotic indices; and (4) a general agreement between the 3 tested biotic indices in describing the lack of global trend for the EcoQs of the Gulf of Lions despite the occurrence of significant changes in benthic macrofauna composition between 1998 and 2010.This study has been carried out with financial support from the French National Research Agency (ANR) in the frame of the Investments for the future Programme, within the Cluster of Excellence COTE (ANR-10-LABX-45).Peer reviewe

From the Idea of a basic income to the political movement in Europe

Volume: 71Start Page: 289End Page: 30

Lentiviral Vectors That Express UGT1A1 in Liver and Contain Mir-142 Target Sequences Normalize Hyperbilirubinemia in Gunn Rats

Background &amp; AimsCrigler–Najjar type 1 (CN-I) is an inherited liver disease caused by an absence of bilirubin–uridine 5′-diphosphate–glucuronosyltransferase (UGT1A1) activity. It results in life-threatening levels of unconjugated bilirubin, and therapeutic options are limited. We used adult Gunn rats (an animal model of the disease) to evaluate the efficiency of lentiviral-based gene therapy to express UGT1A1 in liver. Methods Gunn rats were given intraportal injections of VSVG-pseudotyped lentiviral vectors that encode UGT1A1 under the control of a liver-specific transthyretin promoter (mTTR.hUGT1A1); this vector does not contain target sequences for miR-142, a microRNA that is expressed specifically in hematopoietic cells. Rats were also injected with the vector mTTR.hUGT1A1.142T, which contains 4 copies of the miR-142 target sequences; its messenger RNA should be degraded in antigen-presenting cells. Bilirubinemia was monitored, and the presence of transduced hepatocytes was analyzed by quantitative polymerase chain reaction. Vector expression was tested in vitro in rat hematopoietic cells. Results In Gunn rats, bilirubin levels normalized 2 weeks after administration of mTTR.hUGT1A1. However, hyperbilirubinemia resumed 8 weeks after vector administration, concomitant with the induction of an immune response. In contrast, in rats injected with mTTR-UGT1A1.142T, bilirubin levels normalized for up to 6 months and transduced cells were not eliminated. Conclusions Lentiviral vectors that express UGT1A1 reduce hyperbilirubinemia in immunocompetent Gunn rats for at least 6 months. The immune response against virally expressed UGT1A1 can be circumvented by inclusion of miR-142 target sequences, which reduce vector expression in antigen-presenting cells. This lentiviral-based gene therapy approach might be developed to treat patients with CN-I

Effectiveness of Chest Physiotherapy in Infants Hospitalized with Acute Bronchiolitis: A Multicenter, Randomized, Controlled Trial

Vincent Gajdos and colleagues report results of a randomized trial conducted among hospitalized infants with bronchiolitis. They show that a physiotherapy technique (increased exhalation and assisted cough) commonly used in France does not reduce time to recovery in this population