Čujemo li još Kromanjonca?

This paper is an essay to connect with the stone Age coastal hunters who sheltered 28,000 years ago in the caves of today’s italian Mediterranean sea shore cliffs. We have focused on the archaeological Gravettian layer in the Cavillon cave from Grimaldi occupied by Cro Magnons (informal name for Anatomically Modern Humans of the European Upper Paleolithic), which demonstrates the technical skills of the phase. Cro Magnons, like Neanderthals, were seasonally nomadic; however, the diversity of the resources exploited within the territory along the Grimaldi sea coast suggests a longer term site within which a complex symbolic culture developed.Ovaj nas esej vraća u kameno doba prije 28.000 godina, kada su se lovci sklanjali u pećine na obalnim klisurama Mediterana u italiji. U središtu je pažnje arheološki gravetijenski sloj u špilji Cavillon na nalazištu Grimaldi, koju su nastanili upravo kromanjonci (neslužbeno ime za anatomski moderne ljude iz europ¬skoga gornjeg paleolitika), a koji zorno svjedoči o tehničkim sposobnostima toga razdoblja. Kromanjonci su, baš poput neandertalaca, bili sezonski nomadi, ali se zahvaljujući razno¬likim resursima koje su rabili duž obale nalazišta Grimaldi može zaključiti da su se ondje zadržali duže i razvili složenu simboličku kulturu

Effect of spray cooling on heat transfer in a two-phase helium flow

International audienceIn this paper, we describe an experimental study of the phenomenon of spray cooling in the case of liquid helium, either normal or superfluid, and its relationship to the heat transfer between an atomized diphasic flow contained in a long pipe, and the pipe walls. This situation is discussed in the context of the cooling of the superconducting magnets of the Large Hadron Collider (LHC). Experiments were conducted in a test loop reproducing the LHC cooling system, in which the vapor velocity and temperature could be varied in a large range. Shear induced atomization results in the generation of a droplet mist which was characterized by optical means. The thin liquid film deposited on the walls by the mist was measured using interdigitated capacitors. The cooling power of the mist was measured using thermal probes, and correlated to the local mist density. Analysis of the results shows that superfluidity has only a limited influence on both the film thickness and the mist cooling power. Using a simple model, we show that the phenomenon of spray cooling accounts for the measured non linearity of the global heat transfer. Finally, we discuss the relevance of our results for cooling the final focus magnets (inner triplets) in an upgraded version of the LHC

Visualization in cryogenic environment: Application to two-phase studies

11 pagesInternational audienceThis paper reviews recent technical developments devoted to the study of cryogenic two-phase fluids. These techniques span from simple flow visualization to quantitative measurements of light scattering. It is shown that simple flow pattern configurations are obtained using classical optical tools (CCD cam- eras, endoscopes), even in most severe environments (high vacuum, high magnetic field). Quantitative measurements include laser velocimetry, particle sizing, and light scattering analysis. In the case of mag- netically compensated gravity boiling oxygen, optical access is used to control the poistioning of a bubble subject to buoyancy forces in an experimental cell. Flow visualization on a two-phase superfluid helium pipe-flow, performed as a support of LHC cooldown studies, leads to flow pattern characterization. Visu- alization includes stratified and atomized flows. Thanks to the low refractive index contrast between the liquid and its vapor, quantitative results on droplet densities can be obtained even in a multiple scatter- ing regime

High prevalence of PRPH2 in autosomal dominant retinitis pigmentosa in France and characterization of biochemical and clinical features.

International audiencePURPOSE:To assess the prevalence of PRPH2 in autosomal dominant retinitis pigmentosa (adRP), to report six novel mutations, to characterize the biochemical features of a recurrent novel mutation and to study the clinical features of adRP patients.DESIGN:Retrospective clinical and molecular genetic study.METHODS:Clinical investigations included visual field testing, fundus examination, high-resolution spectral-domain optical coherence tomography (OCT), fundus autofluorescence imaging and electroretinogram (ERG) recording. PRPH2 was screened by Sanger sequencing in a cohort of 310 French families with adRP. Peripherin-2 protein was produced in yeast and analyzed by Western blot.RESULTS:We identified 15 mutations, including 6 novel and 9 previously reported changes in 32 families, accounting for a prevalence of 10.3% in this adRP population. We showed that a new recurrent p.Leu254Gln mutation leads to protein aggregation, suggesting abnormal folding. The clinical severity of the disease in examined patients was moderate with 78% of the eyes having 1 to 0.5 of visual acuity and 52% of the eyes retaining more than 50% of the visual field. Some patients characteristically showed vitelliform deposits or macular involvement. In some families, pericentral RP or macular dystrophy were found in family members while widespread RP was present in other members of the same families.CONCLUSIONS:The mutations in PRPH2 account for 10.3% of adRP in the French population, which is higher than previously reported (0-8%) This makes PRPH2 the second most frequent adRP gene after RHO in our series. PRPH2 mutations cause highly variable phenotypes and moderate forms of adRP, including mild cases which could be underdiagnosed

The “As de Nîmes”, a Roman Coin and the Myth of Antony and Cleopatra: Octavian and Agrippa victorious over Antony

Establishment of Augustus authority in partnership with Agrippa, when Rome was evolving from a “republic” into an empire, led to a political propaganda. The four series of the “Asde Nîmes”, bronze coins struck under Augustus and Agrippa, commemorate the capture of Egyptand the establishment of veterans in Nemausus (Nîmes, France). The iconography of this Roman coin is related to the specific history between 28 BC and 14 AD of Octavian and his general Agrippa, who defeated Mark Antony and Cleopatra at Actium, asexpressed on the reverse, where a crocodile chained to a palm is depicted. Both palm and crocodile symbolize not only the capture of Egypt, but also the defeat of Mark Antony. The palm representsalso the “victory” in a grotesque scene in which his love for Cleopatra converted Antony into aloser. It is then concluded that these coins preserve the memory of Octavian’s victory over theiconic figure of Antony

Velocity intermittency in turbulence : how to objectively characterize it ?

The evolution of $\lambda^2$, a parameter whose definition is recalled in the paper, has been used in order to test various intermittency models in turbulence. This paper aims to validate an experimental, model independent, method for extracting this parameter from the velocity difference probability density functions (pdf). We also discuss the characteristics of an experiment which could push further the analysis of these pdf.L'évolution d'un certain paramètre $\lambda^2$ défini dans l'article a été utilisée pour tenter de trancher entre différents modèles de l'intermittence en turbulence. Le but de cet article est de valider une méthode expérimentale de détermination de ce paramètre, indépendamment de tout modèle, à partir des densités de probabilité de différences de vitesse (pdf). Les conditions expérimentales qui permettraient de pousser plus loin la caractérisation de ces pdf sont également discutées

Affections héréditaires de la rétine dans le Nord -Pas-de-Calais. Dépistage hospitalier et prévalence

The authors present part of a research made on inherited retinal dystrophies recorded among the inhabitants of the Nord -Pas-de-Calais region. This retrospective study extending over a period of 18 years (from 1972 to 1989) and bearing on a population of nearly 4 million inhabitants has enabled us to try and assess the prevalence of each disease. The considerable amount of recorded cases (1 660 patients) corroborates the high frequency of these diseases together with their impact on the socio-economic life and on the health of the population. The distribution of the different forms of these diseases remains very close to the results found by other researchers in other countries.Les auteurs présentent une partie de la recherche entreprise sur les dystrophies rétiniennes héréditaires recensées parmi les habitants de la région du Nord -Pas-de-Calais. Cette étude rétrospective, menée sur 18 années (1972 à 1989) et sur une population proche de 4 millions d'habitants, permet de tenter une estimation de la prévalence pour chacune de ces affections. Le nombre considérable de cas dépistés (1 660 patients) confirme la fréquence et l'importance socio-économique et sanitaire de ces affections. La distribution des différentes formes reste très proche des résultats d'autres études menées en différents pays.Puech Bernard, Kostrubiec Benjamin, Hache Jean-Claude, François Pierre. Affections héréditaires de la rétine dans le Nord -Pas-de-Calais. Dépistage hospitalier et prévalence. In: Hommes et Terres du Nord, 1990/2. Géographie de la scolarité et de la santé. pp. 109-116