171,434 research outputs found
Comportement thermo-mécanique de l'interface sable-structure
No full textInternational audienceLe comportement mécanique de l'interface sol-structure est d'une grande importance en raison du rôle de l'interface dans la résistance due au frottement et la capacité portante des structures. Dans les structures thermo-actives, du fait de la variation de la température, le comportement de l'interface devient plus complexe. L'objectif de ce travail est d'étudier l'effet des variations de température sur le comportement mécanique de l'interface sable-structure. Des essais avec des conditions de charge normale constante (CNL) et de rigidité normale constante (CNS) ont été réalisés dans une boîte de cisaillement direct à différentes températures, 22 et 60 °C sur des éprouvettes sable-sable et sable-structure. Le sable de Fontainebleau a été utilisé. Les résultats ont montré que les variations thermiques appliquées ont un effet négligeable sur la résistance au cisaillement des interfaces sable-sable et sable-structure dans les conditions CNL et CNS et que le comportement du sable peut être considéré comme étant indépendant de la température.The mechanical behaviour of the soil-structure interface plays a major role in the shear characteristics and bearing capacity of foundations. In thermo-active structures, due to non-isothermal conditions, the interface behaviour becomes more complex. The objective of this study is to investigate the effects of temperature variations on the mechanical behaviour of soils and sand-structure interface. Constant normal load (CNL) and constant normal stiffness (CNS) tests were performed on sand and sand-structure interface in a direct shear device at temperatures of 22 and 60 °C. Fontainebleau sand was used. The results showed that the applied thermal variations have a negligible effect on the shear strength of the sand and sand-structure interface under CNL and CNS conditions, and the sand and sand-structure interface behaviour could be considered thermally independent
Breaking into the Boundaries of World Literature: Tahar Ben Jelloun's "L'enfant de sable"
No full textIl presente articolo propone una lettura in prospettiva World Literature del primo romanzo di successo dell’autore franco-marocchino Tahar Ben Jelloun, "L’enfant de sable" (1985). Il ricorso a tale approccio teorico, che si avvale delle intuizioni di Bourdieu e di alcuni studi di Casanova e Damrosch, permette di illustrare in che misura il successo di un lavoro letterario sia il prodotto di intersezioni tra il suo valore estetico e le dinamiche socioeconomiche che regolano il mercato editoriale. Nell’opera di Ben Jelloun, collocata come il suo autore sulla soglia tra due mondi, confluiscono elementi di due sistemi letterari e culturali: quello occidentale e quello arabo-persiano. Ne "L’enfant de sable" è riscontrabile un’ibridità su più livelli – narratologico, intertestuale e linguistico – che può essere interpretata, nel quadro teorico della World Literature, come una strategia di negoziazione tra due culture per incontrare il favore di un pubblico più ampio. Dalla lettura del romanzo in questa prospettiva emergono ambiguità e criticità riguardanti l’opera di Ben Jelloun: da un lato l’accusa di orientalismo forzato per vendere un prodotto conforme alle aspettative dell’Occidente sul Mondo Arabo, dall’altro l’apprezzamento per un’opera in cui l’autore combina magistralmente due culture in una costruzione linguistica e narratologica di innegabile valore estetico, che ha il merito di aprire una finestra di contatto tra due culture.The essay aims to analyze the novel "L’enfant de sable" (1985) – the first bestseller by the French-Moroccan author Tahar Ben Jelloun – in the perspective of World Literature as underpinned by the theories of David Damrosch and Pascale Casanova. This theoretical approach illustrates to what extent the success of a literary work is the product of the intersection between its aesthetic value and the socio-economic dynamics governing the literary market. A global writer on the threshold of two worlds, Ben Jelloun concocts a hybrid work in which Persian-Arabic literary and cultural traditions melt together with their Western counterparts. In particular, L’enfant de sable is characterized by a multilayered hybridity for a strategy of negotiation between the two cultures is employed at many levels: narratological, intertextual and linguistic. This strategy of hybridity/negotiation may be deemed as a mere compromise to reach a larger readership. Indeed, analyzing the novel within this theoretical framework highlights its ambiguities: remarkably, the author has been accused of commodifying his own culture to create a product palatable to the Euro-American market and compliant with Westerners’ expectations about the Arabic world – the topic appealing to French readers being the evidence of it. Yet, this reading also points out the novel’s undeniable aesthetic value: Ben Jelloun succeeds in merging two traditions artfully while opening a window into recondite aspects of Moroccan culture
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
REMARKS ON THE ISLE OF SABLE
No full textGeneral description of the navigation considerations around Sable Island to accompany the Isle of Sable map. The remarks are as follows: "On the days of the new and full moon it is high water along the south shore of the island at half an hour after eight o'clock, and it flows till half an hour past ten o'clock on the north side, and till near eleven o'clock in the pond. Common spring tides rise seven feet perpendicular, and neap tides four. The flood sets in from the south south-west at the rate of half a mile an hour; but it alters its course, and increases its velocity, near the ends of the island. At half flood it streams north, and south at half ebb, with great swiftness across the north-east and north-west bars, therefore dangerous to approach without a commanding breeze. The north-east bar runs out east-north-east about four leagues from the eastern extremity of the island, all of which is very shoal, having in few places more than two, three or four fathoms water; whence it continues east and east by south, deepening gradually to twelve, fifteen and eighteen fathoms of water, at the distance of eight or ten leagues, and shapeth to the south and south-east, sloping gently to sixty and seventy fathoms of water. To the northward and eastward it is very steep, and in a run of three miles the water will deepen to one hundred and thirty fathoms. Abreast the body of the isle the soundings are more gradual. The shoal ground of the north-west bar shapes to the westward, and deepens gradually to seventy fathoms of water, at the distance of twenty or twenty-five leagues from the isle, and winds easterly and southerly until it meets the soundings of the north-east bar. The quality of the bottom in general is very fine sand, with a few small transparent stones; to the northward, and close to the north-east bar, the sand is mixed with many black specks; but near the north-west bar the sand has a greenish colour. The north-east bar breaks in bad weather at the distance of eight and ten leagues from the island; but, in moderate weather, a ship may cross it at five leagues distance with great safety in no less than eight and nine fathoms of water; and, if the weather is clear, the island may be seen thence distinctly from a boat. The north-west bar breaks in bad weather at seven, and sometimes eight, miles from the island; but when the sea is smooth, ships may cross it within the distance of four miles in seven fathoms of water.* Along the north and south sides of the island are many spits of sand extending nearly parallel, and within a mile from the shore. Vessels may anchor on the north-side of the island between these spits, and not be liable to be drove off by southerly winds. On the south-side it is boldest off the body of the island, having ten and twelve fathoms of water within a mile from the shore; but towards the bar it is more shoal and dangerous to approach for the currents, which are uncertain, being in a great degree influenced by the winds which have preceded. The surf beats continually on the shore; and, in calm weather, is heard several leagues off. Landing on this island with boats is practicable on the north side, after a continuance of good weather only. The whole island is composed of fine white sand, much coarser than any of the soundings about it, and intermixed with small transparent stones. Its face is very broken, and hove up in little hills, knobs and cliffs, wildly heaped together, within which are hollows and ponds of fresh water, the skirts of which about with cramberries the whole year, and with blueberries, juniper, &c. in their season, as also with ducks, snipes, and other birds. This sandy island affords a great plenty of beach grass, wild pease, and other herbages, for the support of horses, cows, hogs, &c. which are running wild upon it. It grows no trees, but abundance of wreck and drift wood may be picked up along the shore for fuel. Strong northerly winds shift the spits of sand, and often even choak up the entrance of the pond, which usually opens again by the next southern blast. In this ponds are prodigious numbers of seals, and some flat fish, eels, &c. and on the south-west side lies a bed of remarkably large muscles and clambs. The south shoreis between the cliffs, so low that sea breaks quite over in many places when the wind blows on the island. The Ram’s Head is the highest hill on this island; it has a steep cliff on the north west, and falls gently to the south east. The Naked Sand Hills are one hundred and forty-six feet of perpendicular height above the level of high-water mark, and always appear very white. Mount Knight is in the shape of a pyramid, situated in a hollow between two steep cliffs. Mount Luttrell is a remarkable hummock on the top of a large swelling in the land. Gratia Hill is a knob at the top of a cliff, the height of which is one hundred and twenty-six feet perpendicular above high-water mark. The Vale of Misery is also remarkable; as is Smith’s Flagstaff, a large hill, with a regular ascent in every way. From the offing, the south side of the island appears like a long ridge of sandy cliffs lessening towards the west end, which is very low. The Nova Scotia Banks extend nearly seventy leagues in a westerly direction from the Isle of Sable: They are from twenty to twenty-five leagues wide, and their inner edges are from fourteen to eighteen leagues off shore. They are intersected by narrow winding channels (the bottom of which is mud) running north-west and south-east: Between these banks and the shore are several small inner banks with deep water and muddy bottom. The water deepens regularly from the Isle of Sable to the distance of twenty-two leagues, in fifty fathoms, fine gravel; thence proceeding westward, the gravel becomes coarser. At the distance of twenty-three leagues, and south from Prospect Harbour you have from thirty to thirty-five fathoms of water, large stones; and continuing westward to the western extremity of the banks, the soundings are rocky and shoal to eighteen and fifteen fathoms, Cape Sable bearing north by west, distance fifteen leagues. The south-west extremity of Bank Quero lies twenty-six miles east-north-east half north from the east end of the Isle of Sable. This bank extends E by N thirty-five leagues, and is near eight leagues in width; its shoalest part is about five leagues from its eastern extremity in fifteen and eighteen fathoms of water, slimy sand and clambs; from whence it deepens regularly every way to to sixty and seventy fathoms of water towards the edges of the bank. The bank is steep to, and from its soundings on the north side you fall immediately in ninety or one hundred of water black mud, and in one hundred and twenty fathoms on the south side.
* I have described these bars such as I found them; but as they are composed of shifting sands, repeated storms, and the violence of the sea, may in a course of years considerably alter their form or extent.
Comportement des tirants d'ancrage dans un sable fin
No full textCette étude traite d'une première série d'essais réalisée sur des modèles de tirants d'ancrage horizontaux de dimensions suffisantes pour éviter un effet d'échelle important.Ces tirants étaient constitués par des bulbes cylindriques, métalliques ou en coulis de ciment, de 20 cm de diamètre et de 2 à 4 m de longueur, ancrés sous des hauteurs de sable de 2 à 3 mètres.Ces essais ont apporté une meilleure compréhension du comportement des tirants d'ancrage. Ils ont en particulier permis de préciser l'évolution du frottement latéral et des efforts en tête, en fonction de la charge appliquée au tirant, ainsi que l'importance des zones de rupture dans le sable, au voisinage du tirant
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Durabilité des mortiers de ciment à base du sable recyclé
No full textInternational audienceThe objective of this experimental work is to study the durability of the various compositions of cement mortars with and without additives by substituting natural sand for recycled sand with different volume percentages of: 0, 15, 30, 50, 75and 100%. The mortar mixtures were made from cement CEM I 52.5 and S/C = 3.0. The plasticity of these mortars is kept constant by pre-wetting the recycled sand with an optimum water quantity of 9% by weight of the sand.The results obtained show that the incorporation of recycled sand at a rate of less than 50% improves the compressive strength over time. With 30% recycled sand, the compactness of the mortar is improve d by the filler effect. Recycled mortars have shown remarkable resistance to sulfuric acid aggressions, particularly that of 100% recycled and non-adjuvanted.L'objectif de ce travail expérimental est l'étude de la durabilité des différentes compositions de mortiers de ciment avec et sans adjuvants, en substituant le sable naturel par le sable recyclé avec différents pourcentages volumiques de : 0, 15, 30, 50, 75 et 100 %. Les mélanges de mortiers ont été confectionné à base du ciment CEM I 52,5 et S/C=3,0. La plasticité de ces mortiers est maintenue constante en faisant un pré-mouillage du sable recyclé avec une quantité d'eau optimum de 9% du poids du sable. Les résultats obtenus montrent que l'incorporation du sable recyclé à un taux inférieur à 50% améliore la résistance en compression dans le temps. Avec un pourcentage de 30% de sable recyclé, la compacité du mortier est améliorée par l'effet filler. Les mortiers recyclés ont montré une résistance remarquable vis-à-vis aux agressions de l'acide sulfurique, particulièrement celui composé de 100% recyclé et non adjuvanté
Rare Florida Specimens: Cape Sable Seaside Sparrow
No full textThe publication date refers to the date of collection. A Cape Sable seaside sparrow (Ammodramus maritimus mirabilis) collected by John C. Ogden near Royal Palm Hammock in Everglades National Park. The photo was taken by Wes Biggs on December 1, 1980.https://digitalcommons.usf.edu/fos_images/2410/thumbnail.jp
Hotel Au Sable Chasm, Adirondack Mountains, New York, circa 1901-1907
No full textA color image of the Hotel Au Sable Chasm near Ausable Chasm, an Ausable River Gorge, in Keeseville, New York, circa 1901-1907. The village of Keeseville is located inside the boundaries of New York's Adirondack Park. Postcard number: 897. Postmark date: 1907. Includes message
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