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In the framework of the future High Luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN, most superconducting magnets in the Long Straight Sections will be replaced. Among them, the new D2 recombination dipole will be a He II conduction-cooled magnet with a larger aperture than the LHC dipoles. To provide the required cooling (up to 70 W) to the D2 and to comply with its cryostat integration constraints, a compact heat exchanger was designed by the CEA Département des Systèmes Basses Températures (DSBT) based on a CERN preliminary analysis and a CEA review of the possible cooling schemes. This heat exchanger provides the required heat transfer between the He II pressurized bath and the He II saturated bath to cool the D2 magnet in different operating conditions at 1.8 K and 2 K. The detailed design of the heat exchanger was defined and one prototype was manufactured by industry under the CEA supervision. The heat exchanger prototype is composed of roughly one hundred oxygen-free high purity copper tubes, electron beam welded to the stainless steel He II bath enclosure. The present paper describes the successful cryogenic performance tests of the prototype of the D2 heat exchanger measured in the CEA 400W@1.8K test facility in Grenoble.

After the successful completion of the cryogenic performance tests of the He II heat exchanger prototype for the D2 recombination dipole of the future HL-LHC project at CERN, specific measurements were performed to determine the operation safety margin in case of abnormal operating conditions. This is particularly relevant in case of the failure of liquid helium supply in the He II cold source. For nominal operation, the liquid level is regulated at a constant value and it is not necessary to know its value very accurately. However, in case of a partial drying of the heat exchanger due to discontinuation of the helium liquid supply, it is essential to monitor the absolute value of the liquid level to anticipate any cooling malfunction. This paper describes the procedure for an accurate in-situ He II level measurement as well as for the heat loss and mass flow rate estimates in a He II phase separator. The operation safety margins of the He II heat exchanger prototype for the D2 magnet are then analyzed for the different operating conditions considered during the HL-LHC runs in case of non-nominal liquid level in the He II cold source.

Après l’indépendance du Sénégal le 20 août 1960, Léopold Sédar Senghor dirige le pays.Son parti, l’Union progressiste sénégalaise (UPS), devient l’unique parti au gouvernement. Ce n’est qu’en 1974 que l’opposition démocratique naît avec la création par Abdoulaye Wade du Parti démocratique sénégalais (PDS).Valérie Nivelon a réalisé une enquête pour RFI à Dakar en 2012. Elle a retracé la genèse du PDS d’Abdoulaye Wade. Elle reviendra sur cette naissance du pluralisme politique au Sénégal.Mais cette ouverture de l’espace politique n’a pas donné donné immédiatement naissance à à un système électoral transparent et fiable. L’administration et le parti socialiste au pouvoir, héritier de la culture du parti unique, ont multiplié les obstacles sur le chemin du vote transparent et crédible. Il a fallu trois décennies de luttes acharnées pour faire sauter les uns après les autres les obstacles à la crédibilité du vote au Sénégal.Ibrahima Thioub analyse les moments les plus significatifs de ces luttes, leurs formes et contenus, qui ont permis par deux fois l’alternance politique au Sénégal, sans recourir à des formes extrêmes de violence politique.Abdoulaye Wade, le fondateur du PDS, est élu président de la République du Sénégal en 2000. C'est la première alternance démocratique dans ce pays. Il est réélu en 2007, et tente même de se représenter pour la troisième fois en 2012. Or, la constitution du Sénégal ne permet pas à un président de la République d'exercer le pouvoir plus de deux mandats successifs. Il a alors le projet de modifier la constitution. C'est à cette époque que débutent des mouvements contestataires. Commencée dans la rue en 2011, la contestation du président Abdoulaye Wade s’est finalement transformée en acte électoral, en s’achevant dans les urnes en février et mars 2012.Séverine Awenengo Dalberto a conduit en 2011 et 2012 des travaux sur les élections présidentielles au Sénégal de 2012, notamment sur le mouvement « Y’en a marre » issu des dynamiques contestataires. Au-delà de la contestation de Wade, la réussite de « Y’en a marre » doit beaucoup à sa capacité à incarner les aspirations des jeunes citoyens sénégalais, démographiquement majoritaires mais encore considérés comme des « cadets sociaux ».

International audience

International audience; New D2 recombination dipoles with a larger aperture than in the LHC dipoles are required for the future High Luminosity LHC at CERN. These 13.5 m-long D2 magnets are proposed to be conduction cooled in a static bath of pressurized He II. Their cooling is provided via pressurized He II channels located in the D2 iron yoke and thermally connected to a saturated bath installed at one end of each D2 dipole. The heat transfer between the pressurized He II static bath and the bath pumped down to 16.4 mbar (1.8 K) is performed in a heat exchanger under study at CEA. Various design solutions were studied and evaluated to define the more suitable solution fulfilling on the one hand D2 cooling requirements (up to 70 W) and on the other hand D2 cryostat integration constraints. The paper will report on the D2 cooling needs and constraints, present the studied options and detail the main design features of the selected solution for a compact heat exchanger for D2 dipoles.

A Phase Change Material (PCM) thermal energy storage module was tested in the framework of the Alsolen Sup project. Test results prove not only that the equivalent thermal resistance deduced from the first test campaign does not vary after several months and tens of melting and solidification cycles, but also that our modelling approach is valid both for design and non-nominal power rates, even if the model has to be improved to take into account varying water level and temperature stratification.

Calcium carbonate scaling often is a critical problem for recycled board mills that have closed water circuits. The objective of this study was to determine local scaling risks throughout the production process. To predict scaling potential, we calculated several saturation indexes, based on speciation determined from detailed water analyses. Calculated scaling trends are in accordance with observed dissolution and precipitation of calcium carbonate in the process, when considering local aeration phenomena. The importance of volatile fatty acids (resulting from anaerobic bacterial activity) in calco-carbonic equilibriums is discussed, and taken into account in the speciation calculation. We also demonstrate the need to measure inorganic carbon instead of alkalinity in such conditions. This makes typical scaling indexes, such as the Ryznar Stability Index, irrelevant to predict scaling risk in closed circuit conditions; thus, it is necessary to use general speciation methods, as described in this paper.

Environmental responsibility of papermaking industry leads to intensive reuse of water streams. As well known in chemical engineering, this closure of loops causes the accumulation of soluble species, including calcium ions and inorganic carbon. The result is increased scaling, mainly by calcium carbonate. Due to complex behaviour, predicting scaling in papermaking streams is not straightforward and process water disposal should be kept at a high level in order to prevent scaling. This is contradictory with the objective of preserving the environment. Calcium carbonate precipitation is considered as complex since: - speciation calculation must take into account several complexes and protonated species ( CaC O 3 0 , CaHC O 3 + , CaOH + , HC O 3 − , H 2 C O 3 ) in addition to Ca2+ and C O 3 2 − ; - several polymorphs can precipitate; - the nucleation requires a rather high supersaturation to occur in homogeneous way. We combined a mass balance approach using the CTP proprietary software PS2000 (Ruiz et al., 2003), specially developed for the simulation of actual papermaking plants and the USGS software PHREEQC (Parkhurst and Appelo, 1999), devoted to the speciation in complex aqueous solutions, to predict the local value of the Ionic Activity Product (I.A.P.) in the nodes of paper plants streams. These data were analysed using the results and methodology by Elfil and Roques (2004), comparing the I.A.P. with the solubility products of the three relevant polymorphs (anhydrous calcium carbonate, monohydrate calcium carbonate, calcite) to predict the risk of scaling. A campaign of analysis on an industrial site permitted to benchmark the calculation.

Friedreich's ataxia is the most common inherited ataxia. Ninety-six percent of patients are homozygous for GAA trinucleotide repeat expansions in the first intron of the frataxin gene. The remaining cases are compound heterozygotes for a GAA expansion and a frataxin point mutation. We report here the identification of 10 novel frataxin point mutations, and the detection of a previously described mutation (G130V) in two additional families. Most truncating mutations were in exon 1. All missense mutations were in the last three exons coding for the mature frataxin protein. The clinical features of 25 patients with identified frataxin point mutations were compared with those of 196 patients homozygous for the GAA expansion. A similar phenotype resulted from truncating mutations and from missense mutations in the carboxy-terminal half of mature frataxin, suggesting that they cause a comparable loss of function. In contrast, the only two missense mutations located in the amino-terminal half of mature frataxin (D122Y and G130V) cause an atypical and milder clinical presentation (early-onset spastic gait with slow disease progression, absence of dysarthria, retained or brisk tendon reflexes, and mild or no cerebellar ataxia), suggesting that they only partially affect frataxin function. The incidence of optic disk pallor was higher in compound heterozygotes than in expansion homozygotes, which might correlate with a very low residual level of normal frataxin produced from the expanded allele.

We report on four patients with severe polyneuropathy associated with intestinal pseudoobstruction (MNGIE). Three patients presented characteristic supranuclear ophthalmoplegia, and hyperdense signals on T2 weighted cerebral MRI and dystrophic mitochondria in Schwann cells and in endothelial cells in nerve biopsy specimens. Two of these patients had a Charcot-Marie-Tooth (CMT) presentation. All three were heterozygous for a recessively transmitted double substitution in the TP gene: Glu286Lys/Glu289Ala, Asp156Gly/Leu177Pro and Glu289Ala/Gly387Asp. The fourth patient, who was the only patient of this series with an affected sib, had no oculomotor manifestations, nor T2 hyperdense signals on brain MRI, and no TP gene mutation and or morphological abnormalities of mitochondria on electron microscopic examination. He was the only patient of this series with an affected sib. The three patients with the full MNGIE syndrome died before the age of 30 years. Detailed results of nerve pathology show that severe axonal degeneration is associated with segmental abnormalities of the myelin sheath in this syndrome which appears genetically heterogeneous. Our findings suggest that only ophthalmoplegia and hyperdense signals on cerebral MRI are directly related to the mitochondriopathy.

Cerebral cavernous malformations (CCM) are hamartomatous vascular malformations characterized by abnormally enlarged capillary cavities without intervening brain parenchyma. They cause seizures and focal neurological deficits due to cerebral hemorrhages. CCM loci have already been assigned to chromosomes 7q (CCM1), 7p (CCM2), and 3q (CCM3) and have been identified in 40%, 20%, and 40%, respectively, of families with CCM. Loss-of-function mutations have been identified in CCM1/KRIT1, the sole CCM gene identified to date. We report here the identification of MGC4607 as the CCM2 gene. We first reduced the size of the CCM2 interval from 22 cM to 7.5 cM by genetic linkage analysis. We then hypothesized that large deletions might be involved in the disorder, as already reported in other hamartomatous conditions, such as tuberous sclerosis or neurofibromatosis. We performed a high-density microsatellite genotyping of this 7.5-cM interval to search for putative null alleles in 30 unrelated families, and we identified, in 2 unrelated families, null alleles that were the result of deletions within a 350-kb interval flanked by markers D7S478 and D7S621. Additional microsatellite and single-nucleotide polymorphism genotyping showed that these two distinct deletions overlapped and that both of the two deleted the first exon of MGC4607, a known gene of unknown function. In both families, one of the two MGC4607 transcripts was not detected. We then identified eight additional point mutations within MGC4607 in eight of the remaining families. One of them led to the alteration of the initiation codon and five of them to a premature termination codon, including one nonsense, one frameshift, and three splice-site mutations. All these mutations cosegregated with the disease in the families and were not observed in 192 control chromosomes. MGC4607 is so far unrelated to any known gene family. Its implication in CCMs strongly suggests that it is a new player in vascular morphogenesis.

L'eau est un element essentiel dans la fabrication des papiers et cartons, 95 a 98 % des eaux utilisees pour le procede sont deja recyclees en interne. Les contraintes environnementales incitent les papetiers a reduire toujours plus l'utilisation d'eau claire et a developper des strategies de gestion d'eau conduisant a une production de papiers de qualite avec un minimum d'eau claire. Cet article decrit les difficultes induites par la reduction des utilisations d'eau, mais aussi les bonnes pratiques de gestion des eaux qui permettent d'en diminuer les impacts sur la productivite et le milieu naturel.

In type I blepharophimosis/ptosis/epicanthus inversus syndrome (BPES), eyelid abnormalities are associated with ovarian failure. Type II BPES shows only the eyelid defects, but both types map to chromosome 3q23. We have positionally cloned a novel, putative winged helix/forkhead transcription factor gene, FOXL2, that is mutated to produce truncated proteins in type I families and larger proteins in type II. Consistent with an involvement in those tissues, FOXL2 is selectively expressed in the mesenchyme of developing mouse eyelids and in adult ovarian follicles; in adult humans, it appears predominantly in the ovary. FOXL2 represents a candidate gene for the polled/intersex syndrome XX sex-reversal goat.

Mazabraud syndrome is a rare sporadic disorder, mainly characterized by bone fibrous dysplasia and intramuscular myxomas. We report here two new cases of Mazabraud syndrome. One of our patients (Patient 1) also had café-au-lait spots and multinodular goiter suggestive of McCune-Albright syndrome. We review the 37 previously reported cases with Mazabraud syndrome and discuss the 6/37 patients with criteria of Mazabraud and McCune-Albright syndromes. Based on the clinical overlap between the two syndromes, we tested the GNAS1 gene in blood leukocytes and skin fibroblasts of Patient 1, but found no evidence of an activating mutation in the GNAS1 gene.

Long-term effects of growth hormone (GH) treatment were studied in 59 GH deficient (GHD) children, whose treatment was started before the age of 1 year, during the period 1978-1992, under the supervision of the France-Hypophyse Association. Mean duration of treatment was 8 +/- 3.6 years. At the last evaluation, 20 patients (34%) had a height above normal mean for age, and 50 (85%) had a height above the second lower standard deviation (SD) for age. Final height prediction performed in 29 patients was greater than target size (-0.35 +/- 1.4 SD vs -0.56 +/- 0.79 SD). These results show that early treatment of GHD infants allows normal statural growth in the majority of the cases; in addition, they underline the importance of early diagnosis of GH deficiency.

Prostate-specific antigen (PSA) is a protease able to bind to serum antiproteases as alpha 1 antichymotrypsin (ACT). Free PSA (FPSA) corresponds to the fraction of total PSA (TPSA) which is unbound to ACT. Specific detection of the FPSA seems to be a valuable tool in the distinction between prostatic cancer (PCa) and benign prostatic hyperplasia (BPH). Our aim was to evaluate retrospectively the FPSA/TPSA ratio in comparison to TPSA or FPSA determination, using two new immunoradiometric assays (PSA-RIACT and FPSA-RIACT, CIS bio international, Gif Sur Yvette, France) in the early diagnosis of PCa. 256 men, with TPSA levels between 0.7 and 44.7 ng/ml (median age = 69 years), including 164 sera obtained from patients with BPH and 92 sera from patients with untreated PCa were assayed. All diagnoses were histologically confirmed and patients tested before any adjuvant treatment. The evaluation of the median FPSA/TPSA ratio in the two groups showed significantly different values (BPH group: 24.2%, PCa group: 12.1%, P0.0001). By R.O.C. (Receiver-Operating-Characteristics) analysis, we show that the FPSA/TPSA ratio is the method of choice for discriminating BPH and PCa, since the area under curve is the greatest for the FPSA/TPSA ratio curve, as compared to the TPSA or FPSA curves (P0.0001). The best accuracy (number of true positive + true negative/total = 82.4%) was obtained with a FPSA/TPSA ratioor = 15% with high odds ratio (20.5; confidence interval (CI): 11.2; 37.7). Of interest, similar results were also confirmed even in the subpopulation with serum TPSA levels between 2.5 and 10 ng/ml (161 patients including 99 BPH and 62 PCa). We thus confirm that combined serum measurement of FPSA and TPSA is of particular interest in the early diagnosis of PCa for patients with non-suspicious digital rectal examination and a TPSA value between 2.5 and 10 ng/ml. In those patients, biopsy should be reserved to the cases with FPSA/TPSA below 15%, which allows significant odds ratio (12.8; CI: 5.2; 31.4). Otherwise, to avoid the risk of missing any PCa, usual follow-up with combined TPSA and FPSA determination would be required with the same criteria of biopsy (i.e. FPSA/TPSA ratioor = 15% when TPSA value is between 2.5 and 10 ng/ml; or TPSA10 ng/ml).

Our motivation for undertaking the present survey was to determine the incidence, the distribution, and the clinical features of ischemic and hemorrhagic strokes in children under 16 years old, in a well-defined population-based study. The survey was carried out on the population of the City of Dijon (150,000 inhibitants) from January 1, 1985 to December 31, 1993, collecting prospectively both in adulthood and in childhood (23,877 resident children). Diagnosis of stroke was established on the basis of clinical features and the mechanism was identified by CT scan from 1985 to 1987, and by CT scan and magnetic resonance imaging from 1987 to 1993. When a hemorrhagic stroke was identified, a cerebral arteriogram and an investigation of the coagulation factors were performed. When an ischemic stroke was identified, the following were performed: an ultrasound examination of the cervical arteries, a cerebral arteriogram, a lumbar puncture, an investigation of the coagulation factors and lipid status, a measurement of homocysteine in the plasma and the urine, an electrocardiogram (EKG), a Holter procedure, and a cardiac echography. During the 9 full calendar years of this study we observed 28 stroke patients from a population of 23,877 resident children. There were 17 cases of ischemic stroke, representing some 61% percent of the total, as well as 11 cases of hemorrhagic stroke, 39% percent of the total. The average annual incidence rate was 13.02/100,000 for all strokes, 7.91/100,000 for ischemic strokes, and 5.11/100,000 for hemorrhagic strokes.(ABSTRACT TRUNCATED AT 250 WORDS)

De 1939 au début des années 1950, près d'un million d'Européens sont déportés en URSS, dans des camps de travail ou dans des villages isolés à des milliers de kilomètres de chez eux. C'est ce pan de l'histoire européenne Longtemps occulté et encore largement méconnu qui est raconté ici, à partir de témoignages, source vivante et unique. Les auteurs ont sillonné toute l'Europe, la Russie et le Kazakhstan pour rencontrer ces anciens déportés et recueillir leur parole. Leurs récits, mis en perspective par les auteurs, témoignent de la complexité, trop souvent oubliée, des expériences de déportation, où la violence des ruptures s'accompagne d'une intensité radicale des émotions, entre souffrance et exaltation, entre désespoir et confiance. Des vies intenses faites d'accommodements et de résistance. Une manière originale d'écrire l'histoire à partir du témoignage. Une contribution indispensable à l'historiographie sur les déportations staliniennes.

In patients with androgen insensitivity syndrome (AIS), RFLP study of the androgen receptor gene made it possible to analyze whether deletions or mutations could be responsible for abnormalities in androgen responsiveness. We studied RFLPs of DNA from 25 46,XY patients with partial AIS (PAIS), defined as a concentration of androgen receptor in genital-skin fibroblasts less than 340 fmol/mg DNA, and DNA from 27 46,XY patients with complete AIS (CAIS) with no detectable androgen receptor site. DNA samples were digested with BamHI, EcoRI, HindIII and TaqI restriction enzymes and hybridized with three cDNA probes covering the three domains of the androgen receptor. When we had the maternal and an unaffected brother's DNA, we analyzed the two androgen receptor gene polymorphisms described, the HindIII and the exon 1 CAG repeat polymorphisms, in order to distinguish the two maternal X chromosomes, and to detect carriers of AIS. We did not find any large deletion among the 52 patients. We observed a heterozygous mother in 3 of 14 families studied with the HindIII polymorphism, and in 12 of 25 families using the exon 1 CAG repeat polymorphism. This study suggests that in AIS, abnormalities in androgen receptor response could be related to point mutations or microdeletions rather than to gross structural alterations of the androgen receptor gene. Furthermore, unless the point mutation has been described, exon 1 and HindIII polymorphism studies would enable the identification of carriers in 50% of families, and the prenatal diagnosis of AIS.

National audience

A total of 252 chromosomes from 126 patients with phenylalanine hydroxylase (PAH) deficiencies were analyzed for both mutant genotypes and restriction fragment length polymorphism (RFLP) haplotypes at the PAH locus. The mutant genes studied originated either from Western Europe (116 alleles) or from Mediterranean countries (136 alleles). Only 27% of all mutant alleles were found to carry identified mutations, particularly mutations at codon 252 (2.3%), 261 (7.5%), 280 (6.3%), 408 (3.5%) and at the splice donor site of intron 12 (6.3%). The mutant genotypes were associated with RFLP haplotypes 7, 1, 38, 2 and 3 at the PAH locus respectively. Except for the splice mutation of intron 12, these associations were preferential, but not exclusive, since the other four mutations were found on the background of at least two RFLP haplotypes. These results, together with the observation that 85% of PAH deficient patients are heterozygotes for their mutant genotypes, emphasize the great heterogeneity of PAH deficiencies in Mediterranean countries and hamper systematic DNA testing for carrier status in this population.