bluuebunny/crossref_metadata_2025_split huggingface dataset:
Partir à Londres… pour favoriser l’insertion professionnelle en France
Authors: Santelli Emmanuelle 
Published: March 2014

Dans un contexte d’accroissement des migrations des Français vers Londres, cet article s’attache à comprendre les motivations de jeunes adultes français d’origine maghrébine qui entreprennent cette mobilité dans l’objectif de favoriser leur insertion professionnelle. Une partie de ces jeunes bénéficient en France d’un dispositif d’encouragement à la mobilité internationale. Initié par une mission locale qui accompagne ces jeunes tout au long de leur mobilité, ils sont accueillis par une structure française basée à Londres qui leur propose des annonces d’emploi et de logement. A partir de leur base de données, la première partie de l’article traite des caractéristiques des jeunes selon qu’ils partent dans le cadre d’un dispositif d’accompagnement à la mobilité, ou non. Les premiers subissent plus encore que les seconds une situation à l’égard de l’emploi marquée par la précarité. Ils ne se situent pas non plus au même stade de leur cycle de vie. Ensemble de résultats qui sont confortés et approfondis par l’analyse des entretiens biographiques réalisés avec des jeunes partis quelques mois à Londres. La seconde partie de l’article comporte trois sections reposant sur l’analyse du matériau qualitatif et permet d’aborder leurs motivations à partir, comment à travers cette expérience ils découvrent leur francité et un nouveau mode de vie. Procurant de nouvelles références, c’est tout le processus d’entrée dans la vie adulte qui s’en trouve affecté. Toutefois, cette mobilité est le plus souvent accomplie dans l’idée de favoriser leur insertion professionnelle en France. Loin d’engager une mobilité signe d’une prise de distance, elle marque au contraire leur souhait de partir « pour mieux revenir », car ils sont profondément attachés à leur région d’origine et aux liens familiaux.
Vivre loin de ses parents quand on est un jeune adulte : quel effet sur le lien de confidence?
Authors: Viry Gil , Nada Éva 
Published: March 2014

Dans cet article, nous analysons dans quelle mesure les jeunes adultes mentionnent moins leurs parents comme des partenaires importants de discussion lorsqu’ils vivent éloignés d’eux. À partir d’un échantillon représentatif des jeunes de 18 à 34 ans vivant en Suisse, nous montrons que, d’une manière générale, les jeunes vivant à distance de leurs parents ne sont pas moins nombreux à partager un lien de confidence avec eux. Toutefois, le lien avec les parents est particulièrement sensible à la distance dans le cas des jeunes femmes ayant elles-mêmes des enfants. Pour une jeune femme, avoir un enfant augmente les chances de citer sa mère ou son père comme confidents en situation de proximité géographique et les diminue en cas d’éloignement. De plus, les jeunes mères éloignées de leur milieu d’origine ne trouvent pas ailleurs le soutien affectif qu’elles trouvent habituellement dans la proximité spatiale avec leurs parents. Associée à certains évènements familiaux, la distance géographique contribue dès lors à reconfigurer les dynamiques relationnelles et à renforcer les inégalités de genre au sein des familles. Plus généralement, ces résultats soulignent l’importance d’accorder davantage d’attention à la mobilité et à la distance géographique dans les recherches sur la famille et les relations intergénérationnelles.
Early adolescent pregnancy increases risk of incident HIV infection in the Eastern Cape, South Africa: a longitudinal study
Authors: Christofides Nicola J , Jewkes Rachel K , Dunkle Kristin L , Nduna Mzikazi , Shai Nwabisa Jama , Sterk Claire 
Published: March 2014

IntroductionAdolescents having unprotected heterosexual intercourse are at risk of HIV infection and unwanted pregnancy. However, there is little evidence to indicate whether pregnancy in early adolescence increases the risk of subsequent HIV infection. In this paper, we tested the hypothesis that adolescent pregnancy (aged 15 or younger) increases the risk of incident HIV infection in young South African women.MethodsWe assessed 1099 HIV‐negative women, aged 15–26 years, who were volunteer participants in a cluster‐randomized, controlled HIV prevention trial in the predominantly rural Eastern Cape province of South Africa. All of these young women had at least one additional HIV test over two years of follow‐up. Outcomes were HIV incidence rates per 100 person years and HIV incidence rate ratios (IRRs) estimated by Poisson multivariate models. Three pregnancy categories were created for the Poisson model: early adolescent pregnancy (a first pregnancy at age 15 years or younger); later adolescent pregnancy (a first pregnancy at age 16 to 19 years); and women who did not report an adolescent pregnancy. Models were adjusted for study design, age, education, time since first sexual experience, socio‐economic status, childhood trauma and herpes simplex virus type 2 infection.ResultsHIV incidence rates were 6.0 per 100 person years over two years of follow‐up. The adjusted IRR was 3.02 (95% CI 1.50–6.09) for a pregnancy occurring at age 15 or younger. Women with pregnancies occurring between 16 and 19 years of age did not have a higher incidence of HIV (IRR 1.08; 95% CI 0.64–1.84). Early adolescent pregnancies were associated with higher partner numbers and a greater age difference with partners.ConclusionsEarly adolescent pregnancies increase the incidence of HIV among South African women. The higher risk is associated with sexual risk behaviours such as higher partner numbers and a greater age difference with partners rather than a biological explanation of hormonal changes during pregnancy.
Forecasting air traffic volumes using smoothing techniques
Authors: Önder Emrah , Kuzu Sultan 
Published: March 2014

AbstractFor many years, researchers have been using statistical tools to estimate parameters of macroeconomic models. Forecasting plays a major role in logistic planning and it is an essential analytical tool in countries’ air traffic strategies. In recent years, researchers are developing new techniques for estimation. In particular, this research focuses on the application of smoothing techniques and estimation of air traffic volume. In this study four air traffic indicators including total passenger traffic, total cargo traffic, total flight traffic and commercial flight traffic were used for forecasting. Also seasonal effects of these parameters were investigated. As analysis tools, classical time series forecasting methods such as moving averages, exponential smoothing, Brown’s single parameter linear exponential smoothing, Brown’s second-order exponential smoothing, Holt’s two parameter linear exponential smoothing and decomposition methods applied to air traffic volume data between January 2007 and May 2013. The study focuses mainly on the applicability of Traditional Time Series Analysis (Smoothing & Decomposition Techniques). To facilitate the presentation, an empirical example is developed to forecast Turkey’s four important air traffic parameters. Time Series statistical theory and methods are used to select an adequate technique, based on residual analysis.
Aerosol impacts on drizzle properties in warm clouds from ARM Mobile Facility maritime and continental deployments
Authors: Mann Julian A. L. , Christine Chiu J. , Hogan Robin J. , O'Connor Ewan J. , L'Ecuyer Tristan S. , Stein Thorwald H. M. , Jefferson Anne 
Published: March 2014

AbstractWe have extensively evaluated the response of cloud base drizzle rate (Rcb; mm d−1) in warm clouds to liquid water path (LWP; g m−2) and to cloud condensation nuclei (CCN) number concentration (NCCN; cm−3), an aerosol proxy. This evaluation is based on a 19 month long data set of Doppler radar, lidar, microwave radiometers, and aerosol observing systems from the Atmospheric Radiation Measurement (ARM) Mobile Facility deployments at the Azores and in Germany. Assuming 0.55% supersaturation to calculate NCCN, we found a power law , indicating that Rcb decreases by a factor of 2–3 as NCCN increases from 200 to 1000 cm−3 for fixed LWP. Additionally, the precipitation susceptibility to NCCN ranges between 0.5 and 0.9, in agreement with values from simulations and aircraft measurements. Surprisingly, the susceptibility of the probability of precipitation from our analysis is much higher than that from CloudSat estimates but agrees well with simulations from a multiscale high‐resolution aerosol‐climate model. Although scale issues are not completely resolved in the intercomparisons, our results are encouraging, suggesting that it is possible for multiscale models to accurately simulate the response of LWP to aerosol perturbations.
Mechanisms and cross sections for water desorption from a lunar impact melt breccia
Authors: DeSimone Alice J. , Orlando Thomas M. 
Published: March 2014

AbstractDesorption of H2O (ν = 0) following 157‐nm irradiation of amorphous solid water on a lunar impact melt breccia was measured with resonance‐enhanced multiphoton ionization. Photofragments of vibrationally excited water were detected with nonresonant ionization. The average cross section for H2O (ν = 0) removal and destruction at 0.1 Langmuir (1 L = 10−6 Torr∙s) H2O exposure was measured to be (7.1 ± 1.9) × 10−19 cm2. Cross sections were also measured at 0.3, 1, 5, and 10 L exposures. Because these cross sections increase drastically with decreasing water coverage, water is not expected to remain intact as H2O on the sunlit lunar surface. Instead, photons are likely to cause H2O to desorb or dissociate. The OH+ fragment of H2O (ν*) increased in intensity with increasing irradiation as hydroxyl groups built up on the surface and then recombined. The OH+ signal eventually began to decrease after a dose of 5 × 1018 photons cm−2. Under these conditions, the cross section for H2O (ν*) photodesorption was measured to be 6.4 × 10−20 cm2 for an initial exposure of 5 L H2O.
Tailoring D‐Amino Acid Oxidase from the Pig Kidney to R‐Stereoselective Amine Oxidase and its Use in the Deracemization of α‐Methylbenzylamine
Authors: Yasukawa Kazuyuki , Nakano Shogo , Asano Yasuhisa 
Published: March 2014

AbstractThe deracemization of racemic amines to yield enantioenriched amines using S‐stereoselective amine oxidases (AOx) has recently been attracting attention. However, R‐stereoselective AOx that are suitable for deracemization have not yet been identified. An R‐stereoselective AOx was now evolved from porcine kidney D‐amino acid oxidase (pkDAO) and subsequently use for the deracemization of racemic amines. The engineered pkDAO, which was obtained by directed evolution, displayed a markedly changed substrate specificity towards R amines. The mutant enzyme exhibited a high preference towards the substrate α‐methylbenzylamine and was used to synthesize the S amine through deracemization. The findings of this study indicate that further investigations on the structure–activity relationship of AOx are warranted and also provide a new method for biotransformations in organic synthesis.
Highly Active Bidirectional Electron Transfer by a Self‐Assembled Electroactive Reduced‐Graphene‐Oxide‐Hybridized Biofilm
Authors: Yong Yang‐Chun , Yu Yang‐Yang , Zhang Xinhai , Song Hao 
Published: March 2014

AbstractLow extracellular electron transfer performance is often a bottleneck in developing high‐performance bioelectrochemical systems. Herein, we show that the self‐assembly of graphene oxide and Shewanella oneidensis MR‐1 formed an electroactive, reduced‐graphene‐oxide‐hybridized, three‐dimensional macroporous biofilm, which enabled highly efficient bidirectional electron transfers between Shewanella and electrodes owing to high biomass incorporation and enhanced direct contact‐based extracellular electron transfer. This 3D electroactive biofilm delivered a 25‐fold increase in the outward current (oxidation current, electron flux from bacteria to electrodes) and 74‐fold increase in the inward current (reduction current, electron flux from electrodes to bacteria) over that of the naturally occurring biofilms.
Iron Cyclopentadienone Complexes: Discovery, Properties, and Catalytic Reactivity
Authors: Quintard Adrien , Rodriguez Jean 
Published: March 2014

AbstractIron cyclopentadienone complexes have recently received particular attention in organic chemistry. This is due to their easy synthesis from simple and cheap materials, air–water stability, and most importantly for their unique catalytic features arising from the presence of a non‐innocent ligand, triggering powerful redox properties. Herein we discuss the properties of such complexes from synthetic and mechanistic points of view, and their applications in original redox‐neutral transformations in both racemic and enantioselective series.
A New Pathway of DNA G‐Quadruplex Formation
Authors: Čeru Slavko , Šket Primož , Prislan Iztok , Lah Jurij , Plavec Janez 
Published: March 2014

AbstractA new folding intermediate of Oxytricha nova telomeric Oxy‐1.5 G‐quadruplex was characterized in aqueous solution using NMR spectroscopy, native gel electrophoresis, thermal differential spectra (TDS), CD spectroscopy, and differential scanning calorimetry (DSC). NMR experiments have revealed that this intermediate (i‐Oxy‐1.5) exists in two symmetric bimolecular forms in which all guanine bases are involved in GG N1‐carbonyl symmetric base pairs. Kinetic analysis of K+‐induced structural transitions shows that folding of Oxy‐1.5 G‐quadruplex from i‐Oxy‐1.5 is much faster and proceeds through less intermediates than folding from single strands. Therefore, a new folding pathway of Oxy‐1.5 G‐quadruplex is proposed. This study provides evidence that G‐rich DNA sequences can self‐assemble into specific pre‐organized DNA structures that are predisposed to fold into G‐quadruplex when interacting with cations such as potassium ions.
Amide Synthesis by Nucleophilic Attack of Vinyl Azides
Authors: Zhang Feng‐Lian , Wang Yi‐Feng , Lonca Geoffroy Hervé , Zhu Xu , Chiba Shunsuke 
Published: March 2014

AbstractA method for the synthesis of amide‐containing molecules was developed using vinyl azides as an enamine‐type nucleophile towards carbon electrophiles, such as imines, aldehydes, and carbocations that were generated from alcohols in the presence of BF3⋅OEt2. After nucleophilic attack of the vinyl azide, a substituent of the resulting iminodiazonium ion intermediate migrates to form a nitrilium ion, which is hydrolyzed to afford the corresponding amide.
A Volatile Lactone of Hymenoscyphus pseudoalbidus, Pathogen of European Ash Dieback, Inhibits Host Germination
Authors: Citron Christian A. , Junker Corina , Schulz Barbara , Dickschat Jeroen S. 
Published: March 2014

AbstractThe largely unknown secondary metabolism of the plant pathogenic fungus Hymenoscyphus pseudoalbidus was investigated by use of the CLSA method. A set of volatile lactones was identified by GC/MS. The lactones were synthesized and used in bioassays in which one of the compounds was found to be a strong germination inhibitor for ash seeds, causing necroses in the plant tissue.
Fabrication of natural cellulose microspheres via electrospraying from NaOH/Urea aqueous system
Authors: Wu Weibing , Gu Jun , Zhou Guancheng , Zhang Lei , Gong Murong , Dai Hongqi 
Published: March 2014

ABSTRACTRegenerated cellulose microspheres (RCM) with controllable sizes and architectures are prepared via electrospraying from environmental‐friendly NaOH/Urea aqueous system. The particle size and shape of RCM is mainly dependent on the interplay among the electrical force, surface tension, and viscous force. Particle size can be reduced to a certain extent by increasing voltage and decreasing surface tension, electrode spacing, solution concentration, degree of polymerization, and flow rate. The deformation of droplets, which is peculiarly prone to occur for low viscosity and long electrode spacing, results in elongated spheres, tear‐shaped particles, wedge‐shaped particles, and banding shaped particles besides micorspheres. The sophericity and uniformity of particles generally become worse as a result of the deformation of droplets. RCM possess good porosity and large specific surface area after regeneration. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40656.
A Crucial Role of L‐Selectin in C Protein–Induced Experimental Polymyositis in Mice
Authors: Oishi Kyosuke , Hamaguchi Yasuhito , Matsushita Takashi , Hasegawa Minoru , Okiyama Naoko , Dernedde Jens , Weinhart Marie , Haag Rainer , Tedder Thomas F. , Takehara Kazuhiko , Kohsaka Hitoshi , Fujimoto Manabu 
Published: March 2014

ObjectiveTo investigate the role of adhesion molecules in C protein–induced myositis (CIM), a murine model of polymyositis (PM).MethodsCIM was induced in wild‐type mice, L‐selectin–deficient (L‐selectin−/−) mice, intercellular adhesion molecule 1 (ICAM‐1)–deficient (ICAM‐1−/−) mice, and mice deficient in both L‐selectin and ICAM‐1 (L‐selectin−/−ICAM‐1−/− mice). Myositis severity, inflammatory cell infiltration, and messenger RNA expression in the inflamed muscles were analyzed. The effect of dendritic polyglycerol sulfate, a synthetic inhibitor that suppresses the function of L‐selectin and endothelial P‐selectin, was also examined.ResultsL‐selectin−/− mice and L‐selectin−/−ICAM‐1−/− mice developed significantly less severe myositis compared to wild‐type mice, while ICAM‐1 deficiency did not inhibit the development of myositis. L‐selectin−/− mice that received wild‐type T cells developed myositis. Treatment with dendritic polyglycerol sulfate significantly diminished the severity of myositis in wild‐type mice compared to treatment with control.ConclusionThese data indicate that L‐selectin plays a major role in the development of CIM, whereas ICAM‐1 plays a lesser role, if any, in the development of CIM. L‐selectin–targeted therapy may be a candidate for the treatment of PM.
Mass Spectrometric Investigation of the Reaction between Oxygen Atoms and Carbonyl Sulfide
Authors: Sullivan J. O. , Warneck P. 
Published: March 2014

AbstractThe reaction of oxygen atoms and carbonyl sulfide has been investigated in conjunction with a fast flow system. The following predominant reactions have been found to occur in the early stage,magnified imageThe rate constant at room temperature associated with the first reaction was determined to be k1 = 0.91 ± 0.14 · 10−14 cc/molec. sec and that of the second reaction was estimated as k5 = 4.3 · 10−12 cc/molec. sec. The implications of the chemistry of SO radicals are discussed.
Über den Einfluß von Edelgasen auf die Strahlenchemie des Äthans
Authors: Bünau Ginther 
Published: March 2014

AbstractBei der γ‐Radiolyse von Äthan in Gegenwart eines etwa 25fachen Überschusses an den Edelgasen Argon, Krypton und Xenon entstehen Radiolyseprodukte mit G‐Werten von der gleichen Größenordnung wie bei der Radiolyse von reinem Äthan. Aus diesen G‐Werten lassen sich die Wirkungsgrade der Sensibilisierung durch Edelgas zu ζAr und ζKr ã 1, ζXe ã 0,53 bestimmen. Das mögliche Eingreifen der Edelgasionen in den chemischen Relaismechanismus der Energieübertragung wird diskutiert.
Untersuchung des Reaktionsablaufs in fetten Kohlenwasserstoff‐Sauerstoff‐Flammen II. Versuche an rußenden Acetylen‐Sauerstoff‐Flammen bei niedrigem Druck
Authors: Homann K. H. , Gg. Wagner H. 
Published: March 2014

AbstractDer Vorgang der Rußbildung wird an fetten, vorgemischten Acetylen‐Sauerstoff‐Flammen untersucht, die als flache Flammen bei niedrigem Druck brennen. Zur Analyse der in der Reaktionszone auftretenden gasförmigen Zwischen‐ und Endprodukte werden Proben aus der Flamme über ein Molekularstrahlsystem direkt in die Ionenquelle eines Massenspektrometers gesaugt. Dabei können wegen der weitgehenden Ausschaltung von Wandeinflüssen auch Radikale und andere instabile Zwischenprodukte bestimmt werden. Proben von Rußteilchen lassen sich mittels des gleichen Absaugsystems auf geeigneten Objektträgern auffangen und im Elektronenmikroskop auf ihre Größenverteilung und relative Anzahl in verschiedenen Höhen der Flamme analysieren. Eigenschaften des Absaugsystems und der Einfluß der Sonde auf die Flamme werden beschrieben.Die Bedingungen der Bildung von Polyacetylenen sowie deren Konzentrationen im Gleichgewicht unter‐einander und mit Acetylen werden untersucht und ihre Rolle bei der nachfolgenden Bildung von Ruß diskutiert. Versuche, bei denen zusätzlich Brennstoff von außen in die Flamme injiziert wurde, zeigen, daß die in der Oxydationszone gebildeten Radikale Einfluß auf die später einsetzende Rußbildung haben und daß diese auf der in der ungestörten Flamme zur Verfügung stehenden Meßstrecke noch nicht als abgeschlossen betrachtet werden kann.
Untersuchung des Reaktionsablaufs in fetten Kohlenwasserstoff‐Sauerstoff‐Flammen III. Optische Untersuchungen an rußenden Flammen
Authors: Bonne U. , Gg. Wagner H. 
Published: March 2014

AbstractGleichzeitig mit den in Teil II [1] beschriebenen massenspektrometrischen Messungen über die Rußbildung in flachen Flammen bei niedrigen Drucken wurden spektroskopische Untersuchungen an diesen Flammen ausgeführt. Es wurde die Emission der Radikale C2, CH und OH, der Temperaturverlauf und die OH‐Radikal‐Konzentration innerhalb der Reaktionszone in Abhängigkeit von der Zusammensetzung des Frischgases gemessen. Daneben wurde die Rußmenge vorwiegend durch ihre Absorption bestimmt. Der Verlauf der Rußteilchengröße konnte optisch aus der Differenz von Gas‐ und Teilchentemperatur gewonnen werden.Ferner wurde der Einfluß der Versuchsbedingungen auf die Menge des gebildeten Rußes untersucht.
Etude de la Germination Transitoire en Milieu Condensé
Authors: Gindt R. , Kern R. 
Published: March 2014

AbstractEn solution aqueuse sursaturée, les halogénures alcalins présentent une courbe de cristallisation M(t) à long palier initial tL (temps de latence). En décomposant le phénomène deux parties, fréquence de germination J(t) et croissance m(t) d'un germe critique, on peut déduire la courbe J (t) des courbes expérimentales M (t). La forme de J (t) montre que le régime stationnaire de germination ne s'établit que très lentement. La théorie de la germination transitoire de Frenkel‐Zeldovich jointe à celle de Volmer‐Becker‐Döring, permet d'interpréter ces résultats. Le temps de relaxation du phénomene transitoire serait dû au fait que le milieu est condensé; sa grande variation avec la sursaturation serait liée au phénomène de germination bidimensionnelle.
Über den Mechanismus der Chemilumineszenz von Phthalhydrazid
Authors: Stauff Joachim , Hartmann Gerhard 
Published: March 2014

AbstractDer Mechanismus der Chemilumineszenz der Reaktion zwischen Phthalhydrazid und H2O2, die durch Cu2+ katalysiert wird, wurde durch reaktionskinetische Analyse des zeitlichen Ablaufs der Leuchtintensität und der Sauerstoffentwicklung sowie durch Aufnahme von Differenz‐Absorptionsspektren weiter aufzuklären versucht.Durch Lösen des Geschwindigkeitsgleichungssystems der katalysierten Reaktion mit einem Analogrechner konnte ein Reaktionsschema aufgestellt werden, das die Reaktion zwischen einem um 2 Elektronen ärmeren spektroskopisch nachweisbaren Oxydationsprodukt des Phthalhydrazids und H2O2 als geschwindigkeitsbestimmend für die Anregung zum emissionsfähigen Zustand fordert. Aus dem Ablauf der nicht katalysierten Reaktion, der Hemmbarkeit der Chemilumineszenz durch Radikalfänger und ihrer Anregbarkeit durch Sauerstoffradikale wurde der Schluß gezogen, daß nicht die geschwindigkeitsbestimmende, sondern eine nachfolgende Reaktion zwischen einem Phthalhydrazid‐Semichinon und einem 0,H‐Radikal zur Anregung des Phthalhydrazid‐Anions fuhrt. Die Radikale entstehen vermutlich durch Zersetzung eines Peroxyds. Das Licht wird von der Ketoform des Phthalhydrazids emittiert, die bei 400420 mp ein Fluoreszenzmaximum besitzt, wahrend das der Enolform bei 470–480 mp liegt. Die chemische Anregung des Elektronensystems der leuchtenden Substanz wird durch Aufnahme eines Elektrons in einen angeregten Zustand des um ein Elektron ärmeren Substanzradikals gedeutet.