bluuebunny/crossref_metadata_2025_split huggingface dataset:
Étude théorique et expérimentale de la diffusion des rayons X par les ensembles denses de particules
Authors: Fournet Gérard 
Published: December 2018

L'étude de la diffusion des rayons X aux faibles angles permet d'obtenir des renseignements sur les valeurs et la répartition de la densité électronique de la matière à une échelle comprise entre 10 et 1.000 Å environ.
Cette méthode d'examen est récente : le premier travail systématique et fondamental (thèse de Guinier, réf. 1), date de 1939. Ce mémoire était à peu près uniquement consacré aux cas où les particules sont éloignées les unes des autres ; le but initial de notre travail a été d'étendre à la fois sur le plan théorique et le plan expérimental le champ d'application de cette méthode.
Nous avons cherché à établir une théorie unitaire de la diffusion des rayons X par la matière permettant d'expliquer l'ensemble des faits expérimentaux à partir d'un nombre réduit de paramètres et, en particulier, de relier la diffusion par un fluide aux caractéristiques intrinsèques de ce fluide : densité et forces intermoléculaires. Cette étude montre la nécessité de connaître toute la courbe de diffusion avec une bonne précision pour pouvoir exploiter convenablement les données expérimentales.
Un nouveau dispositif expérimental a donc été mis au point : il est constitué d'un monochromateur double à lames de quartz courbées associé à un tube à anticathode tournante, à foyer fin, fonctionnant sous une forte intensité de courant. Il est ainsi possible d'étudier, avec des temps de pose courts (de l'ordre de l'heure), les hétérogénéités de la matière jusqu'à une échelle de l'ordre de quelques centaines d'angströms alors que l'ancien dispositif ne permettait pas de dépasser 80 Å.
Nous avons ainsi pu étudier certains alliages d'aluminium et des substances d'ordre biologique.
Blue andalusite from Ottré, Venn-Stavelot Massif, Belgium : a new example of intervalence charge-transfer in the aluminium silicate polymorphs
Authors: Langer Klaus , Hålenius Elke , Fransolet André-Mathieu 
Published: December 2018

Blue andalusite from Ottré has been studied by optical, X-ray, microprobe, and single-crystal absorption-spectrometric methods.
Refractive indices are : nα 1.637(1), nβ 1.642(1), nγ 1.647(1) ; Δ(γ-α) = 0.009 ; 2Vα = 88(2)°, optically negative. Lattice constants are a = 7.791(1), b = 7.897(1), c = 5.556(1) Å. Average chemical composition of the blue part is (Al1.959Fe3+0.012Fe2+0.006) [O|Si1.002P0.006O4] and of colourless rims (Al1.909Fe3+0.0105Fe2+0.0015) [O|Si0.999Pb0.0015O4].
The substitution Si4+[4] + M(1)3+[6] = P5+[4] + Fe(1)2+[6] is inferred to cause the incorporation of phosphorus on tetrahedral Si-sites.
The blue colour and the pleochroism of the mineral, X deep blue, Y and Z colourless, is caused by a strong, broad band system, in the E//X(//c) spectrum, centered at around 13 000 cm-1 showing two subbands at 13 400 and 10 900 cm-1. The bands originate from Fe2+-Fe3+ metal-metal charge-transfer transitions. Calculated band positions are 13 858 and 10 118 cm-1.
L'uchucchacuaïte, AgMnPb3Sb5S12, une nouvelle espèce minérale de la série de l'andorite
Authors: Moëlo Yves , Oudin Elisabeth , Picot Paul , Caye René 
Published: December 2018

L'uchucchacuaïte est associée à : galène, alabandite, bénavidésite, sphalérite, pyrite, pyrrhotite et mispickel dans la minéralisation télescopée de Uchuc-Chacua (Pérou).
L'analyse à la microsonde électronique donne Pb 34,8 ; Sb 34,4 ; Ag 5,9 ; Mn 2,8 ; Fe 0,2 ; S 21,1 ; Se 0,3 ; total 99,5 %. Formule : Ag0,98(Mn0,91Fe0,06)Σ0,97 Pb3,04Sb5,09(S11,93 Se5,07)Σ12 idéalement AgMnPb3Sb5S12. L'uchucchacuaïte est pseudo-orthorhombique, de groupe spatial Pmmm, P222 ou Pmm2, avec a = 12,67, b = 19,32 et c = 4,38 Å, Z = 2. Raies les plus intenses du diagramme de poudre : 3,80 (3) (121) ; 3,49 (3) (131) ; 3,30 (10) (250) ; 2,90 (8) (321,051) ; 2,75 (3) (331) ; 2,29 (1) (171) ; 2,19 (1) (511,002) ; 2,08 (3) (531,181). Microdureté Vickers (VHN100) proche de 168 kg/mm2. Densité (calc.) = 5,61. Réflectances maximale et minimale [RMRm(λ] : 44,2 -36,3 (420) ; 43,9 -35,0 (480) ; 43,3 -34,1 (540) ; 42,4 -33,2 (600) ; 41,2 -32,3 (660) ; 39,7 -30,8 (720) ; 39,2 -30,0 (780). Entre polariseurs croisés, le maclage polysynthétique systématique suivant une seule direction serait indicatif d'une symétrie vraie monoclinique.
Cette espèce correspond à un terme faiblement substitué (And50) de la série de l'andorite. La présence de Pb et Mn en proportions identiques en site octaédrique, probablement de manière ordonnée, expliquerait ce faible degré de substitution.
The mafic silicates in the Saint Quay-Portrieux gabbro-diorite intrusion : crystallization conditions of a calc-alkaline pluton
Authors: Fabriès Jacques , Conquéré Fernand , Arnaud Gaston 
Published: December 2018

Les diorites et les gabbros à deux pyroxènes, qui constituent le pluton de Saint Quay-Portrieux, renferment des enclaves comagmatiques de norites à augite et de rares gabbros à olivine. Les silicates mafiques présentent surtout une diminution progressive du rapport mg, un hiatus existant dans les compositions des minéraux entre les gabbros à olivine et les autres termes de la série. Seules les hornblendes montrent des compositions variables à l'échelle de l'échantillon et du cristal ; le zonage se traduit par une diminution de Ti, Al, (Na+K) et une augmentation du rapport mg du cœur vers le bord des cristaux.
Divers calculs thermodynamiques confirment une évolution en deux étapes. Une première cristallisation en profondeur s'est produite pour des températures entre 950 °C et 1 150 °C et des pressions d'environ 9 kbar, dans des conditions sous-saturées en eau, de faible fugacité d'oxygène, et de faible activité de silice, rendant compte du caractère très alumineux des hornblendes précoces. Le deuxième stade de cristallisation eut lieu lors de la mise en place définitive du pluton, à 800 °C-950 °C et 3-4 kbar, avec PH2O ≤ Ptotal. La réaction symptomatique de cet épisode est le remplacement possible de l'orthopyroxène par la cummingtonite. Plusieurs arguments révèlent l'origine magmatique et la stabilité fugace de la cummingtonite, qui ne peut cristalliser dans les diorites que pour des conditions très particulières, impliquant des facteurs à la fois chimiques et cinétiques liés au refroidissement, de sorte qu'elle est généralement remplacée par une hornblende.
Size limits of magnetic-domain engineering in continuous in-plane exchange-bias prototype films
Authors: Gaul Alexander , Emmrich Daniel , Ueltzhöffer Timo , Huckfeldt Henning , Doğanay Hatice , Hackl Johanna , Khan Muhammad Imtiaz , Gottlob Daniel M , Hartmann Gregor , Beyer André , Holzinger Dennis , Nemšák Slavomír , Schneider Claus M , Gölzhäuser Armin , Reiss Günter , Ehresmann Arno 
Published: December 2018

Background: The application of superparamagnetic particles as biomolecular transporters in microfluidic systems for lab-on-a-chip applications crucially depends on the ability to control their motion. One approach for magnetic-particle motion control is the superposition of static magnetic stray field landscapes (MFLs) with dynamically varying external fields. These MFLs may emerge from magnetic domains engineered both in shape and in their local anisotropies. Motion control of smaller beads does necessarily need smaller magnetic patterns, i.e., MFLs varying on smaller lateral scales. The achievable size limit of engineered magnetic domains depends on the magnetic patterning method and on the magnetic anisotropies of the material system. Smallest patterns are expected to be in the range of the domain wall width of the particular material system. To explore these limits a patterning technology is needed with a spatial resolution significantly smaller than the domain wall width.Results: We demonstrate the application of a helium ion microscope with a beam diameter of 8 nm as a mask-less method for local domain patterning of magnetic thin-film systems. For a prototypical in-plane exchange-bias system the domain wall width has been investigated as a function of the angle between unidirectional anisotropy and domain wall. By shrinking the domain size of periodic domain stripes, we analyzed the influence of domain wall overlap on the domain stability. Finally, by changing the geometry of artificial two-dimensional domains, the influence of domain wall overlap and domain wall geometry on the ultimate domain size in the chosen system was analyzed.Conclusion: The application of a helium ion microscope for magnetic patterning has been shown. It allowed for exploring the fundamental limits of domain engineering in an in-plane exchange-bias thin film as a prototypical system. For two-dimensional domains the limit depends on the domain geometry. The relative orientation between domain wall and anisotropy axes is a crucial parameter and therefore influences the achievable minimum domain size dramatically.
The Polarization of the Planet-Hosting WASP-18 System
Authors: Bott Kimberly , Bailey Jeremy , Cotton Daniel V. , Kedziora-Chudczer Lucyna , Marshall Jonathan P. , Meadows Victoria S. 
Published: December 2018

Abstract
We report observations of the linear polarization of the WASP-18 system, which harbors a massive (∼10 M
J) planet orbiting close to its star with an orbital period of 0.94 days. We find that the WASP-18 system is polarized at ∼200 parts-per-million (ppm), likely from the interstellar medium predominantly, with no strong evidence for phase-dependent modulation from reflected light from the planet. We set an upper limit of 40 ppm (99% confidence level) on the amplitude of a reflected polarized light planetary signal. We compare the results with models for a number of processes that may produce polarized light in a planetary system to determine whether we can rule out any phenomena with this limit. Models of reflected light from thick clouds can approach or exceed this limit, but such clouds are unlikely at the high temperature of the WASP-18b atmosphere. Additionally, we model the expected polarization resulting from the transit of the planet across the star and find that this has an amplitude of ∼1.6 ppm, which is well below our detection limits. We also model the polarization due to the tidal distortion of the star by the massive planet and find that this is also too small to be measured currently.
The Effects of Stellar Companions on the Observed Transiting Exoplanet Radius Distribution
Authors: Teske Johanna K. , Ciardi David R. , Howell Steve B. , Hirsch Lea A. , Johnson Rachel A. 
Published: December 2018

Abstract
Understanding the distribution and occurrence rate of small planets was a fundamental goal of the Kepler transiting exoplanet mission, and could be improved with K2 and Transiting Exoplanet Survey Satellite (TESS). Deriving accurate exoplanetary radii requires accurate measurements of the host star radii and the planetary transit depths, including accounting for any “third light” in the system due to nearby bound companions or background stars. High-resolution imaging of Kepler and K2 planet candidate hosts to detect very close (within ∼0.″5) background or bound stellar companions has been crucial for both confirming the planetary nature of candidates, and the determination of accurate planetary radii and mean densities. Here we present an investigation of the effect of close companions, both detected and undetected, on the observed (raw count) exoplanet radius distribution. We demonstrate that the recently detected “gap” in the observed radius distribution (also seen in the completeness-corrected distribution) is fairly robust to undetected stellar companions, given that all of the systems in the sample have undergone some kind of vetting with high-resolution imaging. However, while the gap in the observed sample is not erased or shifted, it is partially filled in after accounting for possible undetected stellar companions. These findings have implications for the most likely core composition, and thus formation location, of super-Earth and sub-Neptune planets. Furthermore, we show that without high-resolution imaging of planet candidate host stars, the shape of the observed exoplanet radius distribution will be incorrectly inferred, for both Kepler- and TESS-detected systems.
Galaxies Probing Galaxies in PRIMUS. II. The Coherence Scale of the Cool Circumgalactic Medium
Authors: Rubin Kate H. R. , Diamond-Stanic Aleksandar M. , Coil Alison L. , Crighton Neil H. M. , Stewart Kyle R. 
Published: December 2018

Abstract
The circumgalactic medium (CGM) close to ∼L* star-forming galaxies hosts strong Mg ii
λ2796 absorption (with equivalent width W
2796 > 0.1 Å) with a near-unity covering fraction. To characterize the spatial coherence of this absorption, we analyze the W
2796 distribution in the CGM of 27 star-forming galaxies detected in deep spectroscopy of bright background (b/g) galaxies first presented in Rubin et al. The sample foreground (f/g) systems have redshifts

and stellar masses 9.1 < log M
*/M
⊙ < 11.1, and the b/g galaxies provide spatially extended probes with half-light radii

at projected distances

< 50 kpc. Our analysis also draws on literature W
2796 values measured in b/g QSO spectroscopy probing the halos of f/g galaxies with a similar range in M
* at z ∼ 0.25. By making the assumptions that (1) samples of like galaxies exhibit similar circumgalactic W
2796 distributions and, (2) within a given halo, the quantity log W
2796 has a Gaussian distribution with a dispersion that is constant with M
* and

, we use this QSO–galaxy pair sample to construct a model for the log W
2796 distribution in the CGM of low-redshift galaxies. Adopting this model, we then demonstrate the dependence of the observed log W
2796 distribution on the ratio of the surface area of the b/g probe to the projected absorber surface area (x
A ≡ A
G/A
A), finding that distributions that assume x
A ≥ 15 are statistically inconsistent with that observed toward our b/g galaxy sample at a 95% confidence level. This limit, in combination with the b/g galaxy sizes, requires that the length scale over which W
2796 does not vary (i.e., the “coherence scale” of Mg ii absorption) is ℓ
A >

kpc. This novel constraint on the morphology of cool, photoionized structures in the inner CGM suggests that either these structures each extend over kiloparsec scales or the number and velocity dispersion of these structures are spatially correlated over the same scales.
Parallel and Perpendicular Diffusion Coefficients of Energetic Charged Particles with Adiabatic Focusing
Authors: Wang J. F. , Qin G. 
Published: December 2018

Abstract
It is very important to understand stochastic diffusion of energetic charged particles in the nonuniform background magnetic field in plasmas of astrophysics and fusion devices. Using different methods considering an along-field adiabatic focusing effect, various authors derived a parallel diffusion coefficient

and its correction T to

, where

is the parallel diffusion coefficient without an adiabatic focusing effect. In this paper, using the improved perturbation method developed by He & Schlickeiser and iteration process, we obtain a new correction

to

. Furthermore, by employing the isotropic pitch-angle scattering model

, we find that

has a different sign from that of T. In this paper, the spatial perpendicular diffusion coefficient

with the adiabatic focusing effect is also obtained.
One-fluid Relativistic Magnetohydrodynamic Equations for a Two-fluid Plasma with the Landau–Lifshitz Radiation Reaction Force
Authors: Liu Wenshuai , Bian Weihao , Zhao Bixuan , Yu Liming , Wang Chan 
Published: December 2018

Abstract
We derive a set of one-fluid relativistic magnetohydrodynamic equations including the Landau–Lifshitz radiation reaction force based on a relativistic two-fluid plasma. These equations could be used in situations where the spatiotemporal scales of the plasma’s motion are sufficiently large.
HSV Susceptibility to Acyclovir – Genotypic and Phenotypic Characterization
Authors: Vikas Raksha , Prabhu Suresha G , Mudgal Piya P , Shetty Ujwal , Karunakaran Kavitha , Jagadesh Anitha , Auti Amogh , Stansilaus Rithu P , Nair Sudheesh , Arunkumar Govindakarnavar 
Published: December 2018

Background Infections due to drug-resistant herpes simplex viruses (HSV) represent an important clinical concern, especially in immunocompromised patients. The present study was aimed at detecting acyclovir (ACV) susceptibility in HSV clinical samples. Methods A total of 13 HSV-positive clinical samples (5 HSV-1 and 8 HSV-2) recovered from patients (1 immunocompromised and 12 of unknown immune status) were included in the study. The genotypic analysis involved an initial UL23 (thymidine kinase) gene sequencing, followed by a confirmatory phenotypic assay using plaque reduction technique. Results Two novel amino acid changes, A37V and H283N, were detected in HSV-1 positive clinical samples, which were found to be susceptible to acyclovir (half maximal effective concentration = 1.5 μM) by plaque reduction assay. Conclusions These two novel amino acid changes could be therefore considered as natural polymorphisms, a phenomenon widely associated with the HSV-UL23 gene.
Structural Insights into the Preferential Binding of PGRP-SAs from Bumblebees and Honeybees to Dap-Type Peptidoglycans Rather than Lys-Type Peptidoglycans
Authors: Liu Yanjie , Zhao Xiaomeng , Huang Jiaxing , Chen Minming , An Jiandong 
Published: December 2018

Abstract
The peptidoglycan recognition protein SAs (PGRP-SAs) from Bombus ignitus (Bi-PGRP-SA), Apis mellifera (Am-PGRP-SA), and Megachile rotundata PGRP-SA (Mr-PGRP-SA) exhibit an intrinsic ability to preferentially bind to Dap-type peptidoglycan (PGN) from Bacillus subtilis rather than Lys-type PGN from Micrococcus luteus. This ability is more analogous to the binding exhibited by PGRP-LCx and PGRP-SD than to that exhibited by PGRP-SA in Drosophila. Moreover, Bi-PGRP-SA and Am-PGRP-SA share greater sequence identity with Drosophila PGRP-LCx than with PGRP-SD and retain several conserved contact residues, including His37/His38, His60/His61, Trp66/Trp67, Ala150/Ala151, and Thr151/Thr152. However, the corresponding contact residue Arg85 is not a major anchor residue in bees (e.g., bumblebees, honeybees, and leaf-cutting bees), and an in silico analysis indicated that the residues Thr151/Thr152 and Ser153/Ser154 of Bi-PGRP-SA and Am-PGRP-SA are deduced to be anchor residues. In addition, the nonconserved residues Asp67 in Bi-PGRP-SA and Mr-PGRP-SA and His68 in Am-PGRP-SA are deduced to be involved in the binding to Dap-type PGNs in bumblebees, honeybees, and leaf-cutting bees. We conclude that the structures and specificities of PGRP-SAs in bees are more analogous to those of PGRP-LCx than to those of Drosophila PGRP-SA. This phenomenon might be explained by the fact that the evolutionary clade of Hymenoptera is more ancient than that of Diptera.
On the Frequency of Algebraic Brauer Classes on Certain Log K3 Surfaces
Authors: Jahnel Jörg , Schindler Damaris 
Published: December 2018

AbstractGiven systems of two (inhomogeneous) quadratic equations in four variables, it is known that the Hasse principle for integral points may fail. Sometimes this failure can be explained by some integral Brauer–Manin obstruction. We study the existence of a non-trivial algebraic part of the Brauer group for a family of such systems and show that the failure of the integral Hasse principle due to an algebraic Brauer–Manin obstruction is rare, as for a generic choice of a system the algebraic part of the Brauer-group is trivial. We use resolvent constructions to give quantitative upper bounds on the number of exceptions.
André Gide et Les fleurs du mal de Baudelaire
Authors: Cigoj Leben Breda 
Published: December 2018

Andre Gide connut à fond le charme de la poésie vers 1885, à l'âge de seize ans, quand on lui permit de fouiller seul dans la bibliothèque de son père. A cette époque il tenait la poésie pour «la fleur et l'aboutissement de la vie» (J. II, 491). Ce fut Victor Hugo dont il apprit par creur nombre de pièces, ce fut surtout Henri Heine, lu d'abord dans la traduction et bientôt dans le texte, qui le boulversèrent profondément: J e me revois, étendu sur le tapis, à I'étrusque, au pied de la petite bibliothèque ouverte, en ce printemps de ma seizième année, tremblant à découvrir, a sentir s'éveiller et répondre à l'appel d'Henri Heine l'abondant priritemps de mon cceur( Ibid., 482).
Agli albori dell’Italiano
Authors: Tekavčić Pavao 
Published: December 2018

Parlare degli albori, dei primi passi dell'italiano, equivale alla discussione sulla ben nota questione: da quando si parla italiano? La domanda è evidentemente di importanza fondamentale per la genesi dell'italiano e il problema è tanto dibattuto che può davvero sembrare impossibile aggiungervi qualcosa di nuovo. Eppure, a nostro avviso, c'è spazio ancora per alcune constatazioni, sia mettendo a fuoco vecchi problemi dal punto di vista della linguistica moderna, sia cercando soluzioni per i problemi ancora aperti. Lo scopo del presente contributo è tuttavia più modesto: esso si propone di illustrare l'esistenza di una determinata serie di fenomeni linguistici, caratteristici per l'italiano, già nei documenti altomedievali scritti in latino, documenti che sono l'unica fonte per l'Alto Medioevo (secoli VII-X all'incirca).1 Abbiamo scelto come corpus il Codice diplomatico longobardo pubblicato da L. Schiaparelli, una delle più importanti raccolte di tali documenti.
Traduttori croati del «canzoniere» - note aggettivali contrastive
Authors: Cernecca Domenico 
Published: December 2018

Se nel paese d'origine la possibilità di diventare petrarchisti nasce dall'imitazione diretta del Petrarca nella sua stessa lingua, nelle nazioni straniere, la radice del petrarchismo inteso nella sua accezione più gene­ rale come «complesso dell'azione esercitata con effetto positivo e negativo dal Petrarca e dai suoi imitatori nella storia della poesia e della lettera­ tura, del pensiero, del costume e della civiltà, va ricercata anzitutto nella traduzione, porta obbligata attraverso la quale sono passati in larga schiera non solo i letterati del passato, ma continuano a passare, sotto forme e appellativi diversi, anche molti letterati e poeti del presente. Prova ne sono non soltanto i debiti artistici diretti e indiretti, confessati o sotterranei e abilmente nascosti della creazione poetica autonoma (i quali possono essere sempre negati e diventare oggetto di polemica), ma anche e soprattutto i saggi di traduzione, a cui sono state sottoposte nel corso dei secoli le rime sparse nelle varie liniue di cultura dell'Europa.
Reggenza e accordo
Authors: Jernej Josip 
Published: December 2018

I rapporti esistenti fra le parole nella frase possono raggrupparsi, com' è noto, in tre categorie: reggenza, funzione e ordine delle parole. La reggenza riguarda il modo in cui alcune parole impongono ad altre certe varizioni di forma (genere, numero, caso, persona). Rientra in questa categoria anche l'accordo. La funzione può definirsi quel rapporto particolare che unisce un elemento costitutivo (un tassema) alla totalità della frase (ovvero all' elemento reggente di un sintagma). L' ordine delle parole comprende le regole che soprassiedono alla sequenza dei "segmenti locutori" nel discorso Questi tre aspetti della sintassi possono venir trattati indipendentemente l' uno dall' altro, tuttavia il concetto di reggenza è talmente legato a quello di funzione che relativi richiami fra questi due concetti riescono inevitabili.
A note of Hittite da-ah-hi
Authors: Schmalstieg William R. 
Published: December 2018

It has long been suggested that the Hittite verb da-ah-hi 'I take' is to be connected with the Indo-European root *dō- ' to give'. (See Friedrich, 1952, 201; Kronasser, 1966, 533-534; Kammenhuber, 1969, 235-236). The pur­pose of this paper is to support this suggestion but in a slightly different way than it has been supported in the past.