1,685 research outputs found
Louis-Charles Damais, un humaniste en Indonésie. Détails d'une vie à Java à travers sa correspondance
No full textJean-Pascal Elbaz
Through a reading of the excerpts of the unpublished correpondence of Louis- Charles Damais, stored in Jakarta, the author attempts to reconstitute the life of a researcher working in Indonesia at the crucial time when the country was making its transition from Dutch colonisation to independence. This short essay points up the problems, both professional and material, which Damais had to face in a country dislocated by the rapid succession of political changes. This article also considers the humanist view of a Westerner for a people trying to regain its dignity by struggling against a colonial system, which Damais himself held to be morally unjustified.Elbaz Jean-Pascal. Louis-Charles Damais, un humaniste en Indonésie. Détails d'une vie à Java à travers sa correspondance. In: Archipel, volume 54, 1997. Destins croisés entre l'Insulinde et la France. pp. 243-252
Using actigraphy versus polysomnography in the clinical assessment of chronic insomnia (retrospective analysis of 27 patients)
No full textThe current study was conducted in order to investigate whether several different methods of characterizing sleep and insomnia symptoms produce different diagnoses. To this aim, we performed a retrospective study in order to compare the outcome of the assessment obtained using polysomnography (PSG) in 27 outpatients complaining of chronic insomnia. Subjects were recruited from a database consisting of patients referred to the sleep centre of the Hotel-Dieu Hospital (Paris) complaining of chronic insomnia. Patients were divided into different groups with regard to type of insomnia. As far as the type of insomnia was concerned, the comparison between actigraphy and PSG showed quite a good contingency coefficient value (C= 0.64). Although this was a preliminary and retrospective study, our results seemed to indicate that actigraphy and PSG were able to lead to a similar output particularly with regard to type of insomnia. Beyond PSG, actigraphy might have a clinical utility in assessing sleep disorders in adults complaining of chronic insomnia
The galaxy's gas content regulated by the dark matter halo mass results in a superlinear M BH-M ∗ relation
No full textSupermassive black holes (SMBHs) are tightly correlated with their hosts, but the origin of such connection remains elusive. To explore the cosmic buildup of this scaling relation, we present an empirically motivated model that tracks galaxy and SMBH growth down to z = 0. Starting from a random mass seed distribution at z = 10, we assume that each galaxy evolves on the star-forming "main sequence" (MS) and each BH follows the recently derived stellar mass (M sstarf) dependent ratio between BH accretion rate and star formation rate, going as . Our simple recipe naturally describes the BH–galaxy buildup in two stages. At first, the SMBH lags behind the host that evolves along the MS. Later, as the galaxy grows in M sstarf, our M sstarf-dependent BHAR/SFR induces a superlinear BH growth, as . According to this formalism, smaller BH seeds increase their relative mass faster and earlier than bigger BH seeds, at fixed M sstarf, thus setting along a gradually tighter M BH–M sstarf locus toward higher M sstarf. Assuming reasonable values of the radiative efficiency epsilon ~ 0.1, our empirical trend agrees with both high-redshift model predictions and intrinsic M BH–M sstarf relations of local BHs. We speculate that the observed nonlinear BH–galaxy buildup is reflected in a twofold behavior with dark matter halo mass (M DM), displaying a clear turnover at M DM ~ 2 × 1012 M ⊙. While supernovae-driven feedback suppresses BH growth in smaller halos (), above the M DM threshold cold gas inflows possibly fuel both BH accretion and star formation in a similar fashion ()
Validation of a new actigraph motion watch versus polysomnography on 70 healthy and suspected sleepdisordered subjects
No full textTraffic-related air pollution in relation to cognitive function in older adults.
No full textBACKGROUND: Few epidemiologic studies have investigated associations of air pollution with cognition in older adults, and none has specifically compared associations across particle sources. We investigated whether exposure to particulate air pollution, characterized by size and source, was associated with cognitive function and decline in cognitive function. METHODS: We included participants of the Whitehall II cohort who were residents of greater London and who attended the medical examination in study wave 2007-2009 (n = 2867). Annual average concentrations of particulate matter (PM) (PM10 and PM2.5 from all sources and from traffic exhaust) were modeled at resolution of 20 × 20 m for 2003-2009. We investigated the relationship between exposure to particles and a cognitive battery composed of tests of reasoning, memory, and phonemic and semantic fluency. We also investigated exposure in relation to decline in these tests over 5 years. RESULTS: Mean age of participants was 66 (standard deviation = 6) years. All particle metrics were associated with lower scores in reasoning and memory measured in the 2007-2009 wave but not with lower verbal fluency. Higher PM2.5 of 1.1 μg/m (lag 4) was associated with a 0.03 (95% confidence interval = -0.06 to 0.002) 5-year decline in standardized memory score and a 0.04 (-0.07 to -0.01) decline when restricted to participants remaining in London between study waves. CONCLUSIONS: This study provides support for an association between particulate air pollution and some measures of cognitive function, as well as decline over time in cognition; however, it does not support the hypothesis that traffic-related particles are more strongly associated with cognitive function than particles from all sources
Metal fluxes through the Strait of Gibraltar: the influence of the Tinto and Odiel rivers (SW Spain)
No full textpeer reviewedA large set of new data concerning dissolved metal concentrations has been acquired in the Gulf of Cadiz and in the Strait of Gibraltar from 1996 to 1999. These data, associated with models (hydrodynamic, tracer advection-dispersion and mixing), have been used to assess the influence of rivers draining the South Iberian Pyrite Belt on the Gulf of Cadiz and on the Atlantic inflow in the Strait of Gibraltar. Metal concentrations in surface waters from the Gulf of Cadiz are maximal near the mouth of the Tinto/Odiel rivers with values exceeding 50 nmol/kg (Mn), 5 nmol/kg (Ni), 30 nmol/kg (Cu), 100 nmol/kg (Zn), 0.9 nmol/kg (Cd) and 45 nmol/kg (As). From the Tinto/Odiel river, a plume of contamination follows the coast in the direction of the Strait of Gibraltar. The computation of a tracer advection-dispersion model confirms that the coastal currents carry the metals discharged from the Tinto and Odiel to the Strait of Gibraltar. From temperature-salinity and metal-salinity plots, four water masses can be recognised in the Gulf of Cadiz and in the Strait of Gibraltar: North Atlantic Surface Water (NASW), North Atlantic Central Water (NACW) and metal-enriched Spanish Shelf Waters from the Gulf of Cadiz (SSW). The Mediterranean Outflow Water (MOW) is also clearly seen at depths greater than 300 m. The chemical characteristics of these various water masses have been used in a mixing model to evaluate their relative contribution to the Atlantic inflow through the Strait of Gibraltar. These contributions are seasonally variable. in June 1997, the contribution was: 80 +/- 20%, 5 +/- 5% and 15 +/- 10% for NASW, NACW and SSW, respectively. In September, the SSW contribution was apparently negligible. Finally, these relative contributions allow the evaluation of the metal fluxes in the Strait of Gibraltar. The presence of SSW in the Strait increases the metal flux to the Mediterranean Sea by a factor of 2.3 (Cu), 2.4 (Cd), 3 (Zn) and 7 (Mn). It does not modify significantly As and Ni fluxes. (C) 2001 Published by Elsevier Science B.V
Les héritiers. Générations et identités chez les Juifs sépharades à Montréal
No full textThe Heirs : Generations and Identifies among Sephardic Jews in Montreal
Mikhael ELBAZ
The author suggests to rethink research on immigrants and their generations, by considering their identification strategies, communal cohesion, reformulations of tradition, class and generational « habitus ». He offers a brief synthesis of the North-American literature on immigrants and their generations and holds that genealogical and cultural identities are constructions which examplify the consequences of modernity. Any analysis of generational positions has to take into account the locations the ascendants maintain in migratory and transethnic networks, material and cultural ressources, the principles of instrumental and symbolic integration in the new country and the power or powerlessness of the immigrants to build a community with institutional completeness. In a brief case study, he compares attitudes and identifications of first and second generation Sephardic Jews in Montreal, showing that the heirs subscribe to panchrony rather than to any nostalgia and act like a third generation, in terms of Hansen 's thesis.Les héritiers : générations et identités chez les Juifs sépharades à Montréal
Mikhaël ELBAZ
L'étude des générations d'immigrants exige de réévaluer sur la longue durée leurs stratégies identitaires ainsi que les relations entre cohésion communautaire, reformulation de la tradition et les habitus de classe et de génération. L'auteur propose une relecture des travaux sur les générations d'immigrants aux États- Unis et soutient que culture généalogique et culture identitaire sont des constructions qui attestent du travail conquérant de la modernité sur les sujets. Il note que toute analyse des trajets générationnels doit rester attentive à la place occupée par les parents dans la chaîne migratoire et dans les réseaux transétatiques, aux ressources matérielles et culturelles dont ils disposent, au cycle économique, aux principes d'intégration instrumentale et symbolique du pays d'accueil, à la capacité ou non des immigrants de fonder un groupe et la représentation de son unité. Dans un second temps, il compare les attitudes et les identités de la première et de la seconde génération de Juifs sépharades à Montréal. Il y décèle que les héritiers putatifs agissent comme une troisième génération en termes du modèle hansenien, se rejudaïsent et se reproduisent selon des logiques familiales et ethniques.Los herederos : generaciones e identidades de los Judíos sefardis en Montreal
Mikhaël ELBAZ
El estudio de generaciones de inmigrantes supone reevaluar sobre el largo plazo sus estrategias identidarias, así como las relaciones entre cohesión comunitaria, nueva formulación de la tradición y costumbres de clase y de generación. El autor propone una nueva lectura de las investigaciones realizadas sobre las generaciones de inmigrantes en Estados Unidos y afirma que cultura genealógica y cultura identidaria son construcciones que demuestran la obra conquistadora de la modernidad sobre los seres. Nota que todo análisis de los trayectos generacionales debe tener en cuenta : el espacio ocupado por lospadres en la cadena migratoria y en las redes trans-estatales ; los recursos materiales y culturales de las que disponen ; el ciclo económico ; los principios de integración instrumental y simbólica del país anfitrión ; la capacidad o no de los inmigrantes en crear un grupo y la representación que tienen de su unidad.
Por otra parte el autor compara las actitudes y las identidades de la primera y de la segunda generación de Judíos sefardis en Montréal. Observa que los herederos putativos actúan como una tercera generación según el modelo « hanseniano », se vuelven a judaízar y se reproducen según lógicas familiares y etnicas.Elbaz Mikhaël. Les héritiers. Générations et identités chez les Juifs sépharades à Montréal. In: Revue européenne des migrations internationales, vol. 9, n°3,1993. Trajets générationnels. Immigrés et « ethniques », France et Québec. pp. 13-34
The main sequence of star-forming galaxies across cosmic times
No full textBy compiling a comprehensive census of literature studies, we investigate the evolution of the main sequence (MS) of star-forming galaxies (SFGs) in the widest range of redshift (0 < z < 6) and stellar mass (108.5–1011.5 M☉) ever probed. We convert all observations to a common calibration and find a remarkable consensus on the variation of the MS shape and normalization across cosmic time. The relation exhibits a curvature towards the high stellar masses at all redshifts. The best functional form is governed by two parameters: the evolution of the normalization and the turnover mass (M0(t)), which both evolve as a power law of the Universe age. The turn-over mass determines the MS shape. It marginally evolves with time, making the MS slightly steeper towards z ∼ 4–6. At stellar masses below M0(t), SFGs have a constant specific SFR (sSFR), while above M0(t) the sSFR is suppressed. We find that the MS is dominated by central galaxies. This allows to turn M0(t) into the corresponding host halo mass. This evolves as the halo mass threshold between cold and hot accretion regimes, as predicted by the theory of accretion, where the central galaxy is fed or starved of cold gas supply, respectively. We, thus, argue that the progressive MS bending as a function of the Universe age is caused by the lower availability of cold gas in haloes entering the hot accretion phase, in addition to black hole feedback. We also find qualitatively the same trend in the largest sample of star-forming galaxies provided by the IllustrisTNG simulation. Nevertheless, we still note large quantitative discrepancies with respect to observations, in particular at the high-mass end. These can not be easily ascribed to biases or systematics in the observed SFRs and the derived MS
Source counts from the 15 mu m ISOCAM deep surveys
No full textWe present the results of the five mid-IR 15 mu m (12-18 mu m LW3 band) ISOCAM Guaranteed Time Extragalactic Surveys performed in the regions of the Lockman Hole and Marano Field. The roughly 1000 sources detected, 600 of which have a flux above the 80% completeness limit, guarantee a very high statistical significance for the integral and differential source counts from 0.1 mJy up to similar to 5 mJy. By adding the ISOCAM surveys of the HDF-North and South (plus flanking fields) and the lensing cluster A2390 at low fluxes and IRAS at high fluxes, we cover four decades in fur from 50 mu Jy to similar to 0.3 Jy. The slope of the differential counts is very steep (alpha = -3.0) in the flux range 0.4-4 mJy, hence much above the Euclidean expectation of alpha = -2.5. When compared with no-evolution models based on IRAS, our counts show a factor similar to 10 excess at 400 mu Jy, and a fast convergence, with alpha = -1.6 at lower fluxes
Lignin-derived bimetallic platinum group metal-free oxygen reduction reaction electrocatalysts for acid and alkaline fuel cells
No full textMetal-nitrogen-carbons (M-N-Cs) as a reliable substitution for platinum-group-metals (PGMs) for oxygen reduction reaction (ORR) are emerging candidates to rationalize the technology of fuel cells. The development of M-N-Cs can further be economized by consuming waste biomass as an inexpensive carbon source for the electrocatalyst support. Herein, we report the simple fabrication and in-depth characterization of electrocatalysts using lignin-derived activated char. The activated char (LAC) was functionalized with metal phthalocyanine (FePc and MnPc) via atmosphere-controlled pyrolysis to produce monometallic M-N-Cs (L_Mn and L_Fe) and bimetallic M1-M2-N-Cs (L_FeMn) electrocatalysts. Raman spectroscopy and transmission electron microscopy (TEM) revealed a defect-rich architecture. XPS confirmed the coexistence of various nitrogen-containing active moieties. L_Fe and L_FeMn demonstrated appreciable ORR in both acidic and alkaline conditions whereas L_FeMn helped in restricting the peroxide yield, particularly in alkaline media. L_Fe and L_FeMn demonstrated remarkable onset potential (Eonset) of -0.942 V (vs RHE) with an E1/2 of 0.874 V (vs RHE) in 0.1 M KOH. In acid, L_FeMn had an Eonset of 0.817 V (vs RHE) and an E1/2 of -0.76 V (vs RHE). Finally, the L_FeMn as a cathode electrocatalyst was integrated and tested in PEMFC and AEMFC. AEMFC demonstrated optimistic performance with a peak power density of 261 mW cm-2 at the current density of -577 mA cm-2
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