Articles de revues : « Erosione arch »

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Ricketts, B. D. « Princess Margaret Arch : re-evaluation of an element of the Eurekan Orogen, Axel Heiberg Island, Arctic Archipelago ». Canadian Journal of Earth Sciences 24, n^o 12 (1 décembre 1987) : 2499–505. http://dx.doi.org/10.1139/e87-234.

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It is argued on the basis of structural, stratigraphic, and sedimentologic criteria that Princess Margaret Arch developed during the principal phase of Eurekan thrusting and folding and therefore is no older than Middle Eocene. Sub-Eureka Sound Group unconformities on eastern Axel Heiberg Island are not associated with uplift on the eastern flank of this arch but are related to erosion of Mesozoic Sverdrup Basin strata over local evaporite diapir domes and ridges. Considerable disparity exists between levels of erosion on the flanks of the arch and the level of erosion along its axis, which cannot be explained by pre-Eocene uplift. Sedimentary facies and textural and petrographic characterisitics of Eureka Sound Group strata do not reflect proximity to an arch. Palynomorph assemblages in the west-derived, syntectonic Buchanan Lake Formation (Middle Eocene) contain reworked latest Cretaceous spores and pollen that were derived from Eureka Sound Group strata originally located on or close to the arch axis.Eureka Sound Group sedimentation in the Axel Heiberg Island – west Ellesmere Island region took place in a single, contiguous basin, rather than in smaller basins that were separated by ancestral Princess Margaret Arch.

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Groom, Robert C., Aaron G. Hill, Bechara F. Akl, Alan M. Speir, Paul S. Massimiano, Edward A. Lefrak, Derek D. Muehrcke et Delos M. Cosgrove. « Cannula length and arch flow erosion ». Annals of Thoracic Surgery 61, n^o 2 (février 1996) : 773–74. http://dx.doi.org/10.1016/0003-4975(96)89379-9.

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Feinstein, S., G. K. Williams, L. R. Snowdon, F. Goodarzi et T. Gentzis. « Thermal maturation of organic matter in the Middle Devonian to Tertiary section, Fort Norman area (central Mackenzie Plain) ». Canadian Journal of Earth Sciences 28, n^o 7 (1 juillet 1991) : 1009–18. http://dx.doi.org/10.1139/e91-092.

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The Fort Norman area is marked by a complex structural and depositional history with temporally and spatially variable temperature and maturity gradients. Maturity of the Middle Devonian Canol – Hare Indian unit indicates two terrains of markedly different paleotemperatures and thermal gradients, roughly coinciding with the Palaeozoic Keele Arch (north) and Root Basin (south), with a sharp transition (lateral discontinuity) between them. Maturity of the unconformably overlying Cretaceous to early tertiary section is lower and laterally continuous across the entire study area, showing no relation to the sub-Cretaceous structures. The vertical maturity profile in the southern terrain is unique in that two discontinuous segments record markedly different thermal histories, neither of which is related to present burial conditions. Maturity of the Devonian formations was established some time prior to the sub-Cretaceous erosion, whereas that in the Cretaceous to Tertiary section postdates Palaeocene but predates a major part of the later Tertiary deformation and erosion. In contrast, the continuous maturity profile recorded in the northern terrain reflects a significant effect of the Tertiary thermal conditions, indicating much lower thermal gradients in the Keele Arch than in the Root Basin during the early phase of maturation. Along with the structural pattern and sedimentary history, the striking differences indicated in the thermal gradients between the Root Basin and the Keele Arch suggest a strike-slip-related pull-apart or another stretching mechanism for the Root Basin in contrast to the compression in the Keele Arch. In addition to the characterization of the regional thermal history and its variation with time, the maturity pattern obtained allows some estimate to be made of the thickness of the eroded section and timing of the major erosional phases.

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Hannon, Chris J., et Ben J. Evans. « Solid particle erosion protection for the BLOODHOUND SSC front wheel arches ». Proceedings of the Institution of Mechanical Engineers, Part L : Journal of Materials : Design and Applications 232, n^o 12 (13 juillet 2016) : 1012–22. http://dx.doi.org/10.1177/1464420716659777.

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BLOODHOUND SSC is a World Land Speed Record Vehicle designed to travel at speeds of up to 1050 mph (469 m·s−1), with the lower chassis and suspension extremely close to the ground. The shockwave from the nose of the car is expected to fluidise the desert surface of the track in Hakskeen Pan, South Africa. Sacrificial materials must be added to the exterior of the car to limit erosive wear. An open loop gas blast erosion rig was used to test materials at velocities predicted by computational fluid dynamics in the front wheel arches, an area highlighted by the BLOODHOUND SSC engineers as requiring extensive protection. Tests of potential erosion protection materials were performed at 15° and 90° Impact angle using alumina as a substitute for Hakskeen Pan soil. Testing resulted in the use of a 2-mm thick Kevlar 49 laminate and 1.2 mm thick titanium Ti 15 V-3Cr-3Sn-3Al sheet for the wheel arch liner, with titanium Ti 6Al-4V used for the wheel arch lip. The erodent mass flow rate for the application was an unknown variable during testing; the test rig used a specific erodent mass flow rate of approximately 300 kg·m−2·s−1. Depending on in-service erosion rates, the titanium liner may be replaced with either a more durable liner made from Stellite 6B or a less dense liner made from aluminium Al 6082-T6.

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Benedetti, Alice, Alvise Del Monte, Maurizio Rubino et Daniela Mancuso. « 506 Uneventful pseudoaneurysm of the ascending aorta with sternal erosion in pregnancy ». European Heart Journal Supplements 22, Supplement_N (1 décembre 2020) : N142—N145. http://dx.doi.org/10.1093/eurheartj/suaa210.

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Abstract A 36-year-old woman at 31 weeks’ gestation presented with exertional dyspnoea and palpitations. She had a history of bicuspid aortic valve treated with surgical aortic valvotomy for severe stenosis, followed by ascending aorta replacement for type A acute aortic dissection and Bentall operation with a mechanical valve for severe aortic regurgitation. Eight years after the last surgery, magnetic resonance angiography showed aortic arch aneurysm (49 mm) with a small intimal flap. Thereafter, the patient was lost to follow-up until the current admission. She was hemodynamically stable on presentation and physical examination was unremarkable apart from a mechanical second heart sound. The electrocardiogram showed sinus rhythm with left bundle branch block (Panel A). Transthoracic echocardiography revealed severe left ventricular dilation (EDV 90 ml/m2) with mild dysfunction (EF 50%), normal prosthetic aortic valve function, and aortic arch dilation (50 mm) (Panel B and C). After a multidisciplinary evaluation, elective cesarean section was performed at 34 weeks’ gestation. A post-delivery aortic computed tomography angiography revealed aortic arch aneurysm (52 mm) with intimal flap and two pseudoaneurysms of the anterior aortic wall causing sternal erosion (Panel D, E, F and G). Subsequently, the patient underwent ascending aorta and aortic arch replacement by Frozen Elephant Trunk technique with a 24 x130 mm prosthesis between the aortic root and the descending aorta. The postoperative course was uneventful, and the patient was discharged to a cardiac rehabilitation centre.

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Li, Yaohuang. « Namtso Ancient Lagoon and Ancient Sea Erosion Landform ». E3S Web of Conferences 206 (2020) : 01015. http://dx.doi.org/10.1051/e3sconf/202020601015.

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During a certain geological period, the sea surface is at the current elevation of about 4746-4755 meters. When the sea surface is about 4746-4755 meters above sea level, the Namtso region of Tibet is a lagoon in the sea. The sea surface was kept stable at the above location for a long time, and a lot of sea erosion landforms were generated on the coast. The ancient sea erosion caves, sea erosion pillars, sea erosion arch bridges, sea erosion headlands, sea erosion headlands, sea erosion cliffs, sea erosion platforms and other various ancient sea erosion micro-landforms are well preserved on the banks of Namtso Lake. It is a unique and natural ancient coastal landscape park in the world

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Chidsey, Thomas, Jr, et Grant Willis. « Landscape Arch, Delicate Arch, and Double Arch in Arches National Park, Southeastern Utah ». Geosites 1 (11 mars 2020) : 1–12. http://dx.doi.org/10.31711/geosites.v1i1.54.

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Arches National Park in southeastern Utah has the greatest concentration of natural rock arches in the world. The park is located in a geologic region called the Paradox fold and fault belt in the northern Paradox Basin and showcases spectacular and classic Colorado Plateau geology with its colorful sedimentary rocks, ancient sand dunes, cliffs, domes, fins, and pinnacles, as well as the arches. The arches in the park and the surrounding region were formed by a unique set of circumstances involving Middle Pennsylvanian (about 308 million years ago [Ma]) to Late Triassic (200 Ma) movement of subsurface salt layers, Middle Pennsylvanian to Late Cretaceous (about 70 Ma) deposition, and Tertiary and Quaternary (23 Ma to the present) folding, faulting, erosion, and salt dissolution. Massive, hard, brittle sandstones jointed by folding, resting on or containing soft layers or partings, and located near fold structures such as salt-cored anticlines undergoing dissolution, and a dry climate, all favor the formation of arches. Rarely do all these phenomena occur in one place, but they do in Arches National Park.The Natural Arch and Bridge Society (NABS) stated, “A natural arch is a rock exposure that has a hole completely through it formed by the natural, selective removal of rock, leaving a relatively intact frame.” They also make it clear that a natural bridge (which is at least partially formed by flowing water) is one type of natural arch (NABS website) (see A Bit of Perspective, below, for more explanation). Using their own criteria, Stevens and McCarrick (1988) catalogued over 2000 natural arches in Arches National Park; most have unique characteristics that could qualify them as geosites. However, the three most famous arches in the park, and perhaps the world, are Landscape Arch, Delicate Arch, and Double Arch, and thus these were selected as the geosites for this paper.

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Rukosujew, Andreas, Raluca Weber, Bernd Kasprzak et Angelo Maria Dell’Aquila. « Stent erosion after treatment of coarctation of right-sided aorta and successful surgical management ». European Journal of Cardio-Thoracic Surgery 57, n^o 5 (21 octobre 2019) : 1007–8. http://dx.doi.org/10.1093/ejcts/ezz281.

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Abstract We present a case of surgical treatment of a pseudoaneurysm of the right-sided aortic arch after stent implantation for primary coarctation in a 36-year-old woman with a previous history of ventricle septal defect closure in early childhood. As a first step, she underwent a left carotid to subclavian artery bypass for an aberrant left subclavian artery and as a second step a ‘beating heart’ aortic arch and descending aorta replacement via resternotomy. The postoperative course was uneventful.

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Caputo, Mario Vicente, et Emilio Alberto Amaral Soares. « Eustatic and tectonic change effects in the reversion of the transcontinental Amazon River drainage system ». Brazilian Journal of Geology 46, n^o 2 (juin 2016) : 301–28. http://dx.doi.org/10.1590/2317-4889201620160066.

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ABSTRACT: The development of the transcontinental Amazon River System involved geological events in the Andes Chain; Vaupés, Purus and Gurupá arches; sedimentary basins of the region and sea level changes. The origin and age of this river have been discussed for decades, and many ideas have been proposed, including those pertaining to it having originated in the Holocene, Pleistocene, Pliocene, Late Miocene, or even earlier times. Under this context, the geology of the sedimentary basins of northern Brazil has been analyzed from the Mesozoic time on, and some clarifications are placed on its stratigraphy. Vaupés Arch, in Colombia, was uplifted together with the Andean Mountains in the Middle Miocene time. In the Cenozoic Era, the Purus Arch has not blocked this drainage system westward to marine basins of Western South America or eastward to the Atlantic Ocean. Also the Gurupá Arch remained high up to the end of Middle Miocene, directing this drainage system westward. With the late subsidence and breaching of the Gurupá Arch and a major fall in sea level, at the beginning of the Late Miocene, the Amazon River quickly opened its pathway to the west, from the Marajó Basin, through deep headward erosion, capturing a vast drainage network from cratonic and Andean areas, which had previously been diverted towards the Caribbean Sea. During this time, the large siliciclastic influx to the Amazon Mouth (Foz do Amazonas) Basin and its fan increased, due to erosion of large tracts of South America, linking the Amazon drainage network to that of the Marajó Basin. This extensive exposure originated the Late Miocene (Tortonian) unconformity, which marks the onset of the transcontinental Amazon River flowing into the Atlantic Ocean.

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Ruocci, Gianluca, Rosario Ceravolo et Alessandro de Stefano. « Modal Identification of an Experimental Model of Masonry Arch Bridge ». Key Engineering Materials 413-414 (juin 2009) : 707–14. http://dx.doi.org/10.4028/www.scientific.net/kem.413-414.707.

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The erosion of the river bed material at bridge pier foundation produced by scour events is one of the main causes of the observed masonry bridges failures and collapses. Foundation settlements and rotations derived from the reduction of the footprint under the piers threaten masonry arch bridges integrity more than any gravity load. The resulting effect on the structure is the development of cracking mechanisms on the arches which may affect the dynamic behaviour of the whole bridge. A scaled experimental model of a masonry arch bridge has been built in the laboratory of the Dep. of Structural Engineering at the Politecnico di Torino. The aim was to better understand scour damage scenario and to identify early structural symptoms of pier erosion. A preliminary dynamic identification is carried out on the intact structure and a comparison with the FEM results is performed. The set of identified modal parameters is adopted as the reference system that will be compared with those acquired after the application of damage of increasing extent.

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Curtis, Michael, Simon Holford, Mark Bunch et Nick Schofield. « Controls on the preservation of Jurassic volcanism in the Northern Carnarvon Basin ». APPEA Journal 61, n^o 2 (2021) : 600. http://dx.doi.org/10.1071/aj20137.

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The Northern Carnarvon Basin (NCB) forms part of the North West Australian margin. This ‘volcanic’ rifted margin formed as Greater India rifted from the Australian continent through the Jurassic, culminating in breakup in the Early Cretaceous. Late Jurassic to Early Cretaceous syn-rift intrusive magmatism spans 45000km2 of the western Exmouth Plateau and the Exmouth Sub-basin; however, there is little evidence of associated contemporaneous volcanic activity, with isolated late Jurassic volcanic centres present in the central Exmouth Sub-basin. The scarcity of observed volcanic centres is not typical of the extrusive components expected in such igneous provinces, where intrusive:extrusive ratios are typically 2–3:1. To address this, we have investigated the processes that led to the preservation of a volcanic centre near the Pyrenees field and the Toro Volcanic Centre (TVC). The volcanic centre near the Pyrenees field appears to have been preserved from erosion associated with the basin-wide KV unconformity by fault-related downthrow. However, the TVC, which was also affected by faulting, is located closer to the focus of regional early Cretaceous uplift along the Ningaloo Arch to the south and was partly eroded. With erosion of up to 2.6km estimated across the Ningaloo Arch, which, in places, removed all Jurassic strata, we propose that the ‘Exmouth Volcanic Province’ was originally much larger, extending south from the TVC into the southern Exmouth Sub-basin prior to regional uplift and erosion, accounting for the ‘missing’ volume of extrusive igneous material in the NCB.

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Sayer, Derek. « Great Arches Viewed from the Coasts of Bohemia : Reflections Inspired by Tables of Kings1 ». New Perspectives 24, n^o 2 (septembre 2016) : 73–90. http://dx.doi.org/10.1177/2336825x1602400205.

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Considering the differences between the superficial orderliness of the English/British table of royal succession and the apparent anarchy of its Bohemian counterpart, this essay questions aspects of the analysis of English state formation offered in Philip Corrigan and Derek Sayer's 1985 study The Great Arch: English State Formation as Cultural Revolution. Rather than providing a contrast to England's institutional political continuities over centuries, Bohemia's manifestly fractured history furnishes a vantage point from which the ideological character of such claimed historical continuities becomes clear. E. P. Thompson's image of a “great arch” of state formation attributes far too much shape, solidity, and coherence to a process that was always, whether in England or Bohemia, a matter of flux and fluidity – a landscape in constant erosion, upon which coherence is only ever imposed in momentary retrospect.

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Sayer, Derek. « Great Arches Viewed from the Coasts of Bohemia : Reflections Inspired by Tables of Kings1 ». New Perspectives 26, n^o 2_suppl (juin 2018) : 97–114. http://dx.doi.org/10.1177/2336825x1802602s04.

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Considering the differences between the superficial orderliness of the English/British table of royal succession and the apparent anarchy of its Bohemian counterpart, this essay questions aspects of the analysis of English state formation offered in Philip Corrigan and Derek Sayer's 1985 study The Great Arch: English State Formation as Cultural Revolution. Rather than providing a contrast to England's institutional political continuities over centuries, Bohemia's manifestly fractured history furnishes a vantage point from which the ideological character of such claimed historical continuities becomes clear. E. P. Thompson's image of a “great arch” of state formation attributes far too much shape, solidity, and coherence to a process that was always, whether in England or Bohemia, a matter of flux and fluidity – a landscape in constant erosion, upon which coherence is only ever imposed in momentary retrospect.

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Jordan, Benjamin R. « Intermittent but Rapid Changes to Coastal Landscapes : The Tsunami and El Niño Wave-Formed Sea Arch at Laie Point, Oahu, Hawaii, U.S.A. » Geosciences 11, n^o 3 (23 mars 2021) : 147. http://dx.doi.org/10.3390/geosciences11030147.

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Kukuiho’olua Island is an islet that lies 164 m due north of Laie Point, a peninsula of cemented, coastal, Pleistocene and Holocene sand dunes. Kukuiho’olua Island consists of the same dune deposits as Laie Point and is cut by a sea arch, which, documented here for first time, may have formed during the 1 April 1946 “April Fools’s Day Tsunami.” The tsunami-source of formation is supported by previous modeling by other authors, which indicated that the geometry of overhanging sea cliffs can greatly strengthen and focus the force of tsunami waves. Additional changes occurred to the island and arch during the 2015–2016 El Niño event, which was one of the strongest on record. During the event, anomalous wave heights and reversed wind directions occurred across the Pacific. On the night of 24–25 February 2016, large storm waves, resulting from the unique El Niño conditions washed out a large boulder that had lain within the arch since its initial formation, significantly increasing the open area beneath the arch. Large waves also rose high enough for seawater to flow over the peninsula at Laie Point, causing significant erosion of its upper surface. These changes at Laie Point and Kukuio’olua Island serve as examples of long-term, intermittent change to a coastline—changes that, although infrequent, can occur quickly and dramatically, potentially making them geologic hazards.

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Queiroz, Andressa Cristina da Silva, Robson de Lima Gomes, Gregorio Marcio de Figueiredo Rodrigues et Viviane Maria Gonçalves De Figueiredo. « Tomada de arco facial e montagem de articulador semi-ajustável para diagnóstico oclusal – relato de caso ». Full Dentistry in Science 13, n^o 49 (2021) : 125–34. http://dx.doi.org/10.24077/2021;1349-125134.

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Objective: It consists of reporting a clinical case of taking a facial arch and assembling a semi-adjustable articulator (ASA) for occlusal diagnosis. Case report: A 22-year-old female patient sought dental care because she was sensitive to element 24. It was clinically observed that the patient had a non-carious cervical lesion. The patient showed a physiological occlusion and an unfavorable positioning of elements 22 and 23. Thus, an attempt was made to investigate the presence of abrasive and erosive habits, which were not reported by the patient. Thus, a clinical evaluation and model assembly in ASA was conducted to identify possible occlusal interference, which would be triggering such injury. The following figures report the clinical case, occlusal registration, taking the facial arch itself, removing the facial arch, angulation adjustments in the ASA, mounting the upper and lower model in the position of maximum usual intercuspation. Conclusion: The use of the semi-adjustable articulator and the facial arch contributed to the diagnosis, planning and treatment of the case. Therefore, these instruments must be part of the dental surgeon’s clinical practice in order to offer greater predictability during oral rehabilitation.

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El Bouanani, Latifa, Khadija Baba, Ghizlane Ardouz et Fatima Ezzahraa Latifi. « Parametric Study of a Soil Erosion Control Technique : Concrete Lozenges Channels ». Civil Engineering Journal 8, n^o 9 (1 septembre 2022) : 1879–89. http://dx.doi.org/10.28991/cej-2022-08-09-09.

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A new technique, "the concrete lozenges channels" is described in this paper. It is an erosion control measure to attenuate the water soil loss quantity to a tolerable level. These are open inclined channels that form lozenges on the slope. In fact, they drain rainfall, runoff, and sediments alongside the slope into the ditch. Using the RUSLE erosion model for erosion assessment, the parameters that had the most influence on the percentage decrease of the soil erodibility are discussed. A comparison between techniques already used, that is, the concrete arches and the concrete lozenge channels proposed in this paper, makes it possible to mention the shortcomings and the strengths of each technique. In fact, the percentage decrease in erosion soil loss is about 42% for 2 arches and is about 49% for 2 lozenges. If the number of channels present on the slope increases, the area exposed to erosion decreases. By comparing the study case, the exposed area for one lozenge is less by 39% to 68% than the exposed area for one arch. The total perimeter lengths are comparable. In this article, a parametric study is undertaken to define the optimum dimensions and optimum number of concrete inclined channels. The ditch section and the inclined channel section are determining factors in the lozenge sizing. Doi: 10.28991/CEJ-2022-08-09-09 Full Text: PDF

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Eliachar, Isaac, Robert J. Stegmoyer, Howard L. Levine, Edward D. Sivak, Atul C. Mehta et Harvey M. Tucker. « Planning and Management of Long-Standing Tracheostomy ». Otolaryngology–Head and Neck Surgery 97, n^o 4 (octobre 1987) : 385–90. http://dx.doi.org/10.1177/019459988709700408.

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Long-term effects of tracheostomy can include structural changes in the anterior tracheal wall and larynx as a result of pressure, friction, and deformation by the relationship between the curved cannula, the trachea, the larynx, and the upper border of the sternum. High-placed stoma, flexed cervical position, and short, obese necks are predisposing anatomic relationships, in some long-standing tracheostomies, progressive erosion of the upper anterior tracheal wall and cricoid arch is observed, often with secondary subglottic stenosis. No discussion of measures to prevent or correct these problems was found in a review of the literature. This article discusses surgical techniques to (1) prevent laryngotracheal erosion and (2) repair and reconstruct an airway that is already damaged. A superiorly based tracheostomy flap and a muscular sling are designed to buttress the tracheostomy. Results and follow-up are also reported.

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Gonzalez, Wilma B. Aleman, Jean M. Self-Trail, W. Burleigh Harris, Jessica Pierson Moore et Kathleen M. Farrell. « Depositional sequence stratigraphy of Turonian to Santonian sediments, Cape Fear arch, North Carolina Coastal Plain, USA ». Stratigraphy 16, n^o 1 (11 décembre 2020) : 293–314. http://dx.doi.org/10.29041/strat.17.4.293-314.

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ABSTRACT: A new sequence stratigraphic framework for Turonian to Santonian (94-84 Ma) sediments is established using data from the USGS Kure Beach and Elizabethtown cores collected from the Atlantic Coastal Plain of North Carolina (NC). These sediments represent some of the oldest marine units deposited on the southeastern Atlantic Coastal Plain and record the early development of a clastic wedge atop crystalline basement. Sediments were deposited as transitional marginal-marine to marine units in a complex interplay of fluvial, estuarine, and shelf environments. Repetitive lithologies and minimal biostratigraphic control requires an integrated analysis of grain-size data, geophysical logs, biostratigraphy, and 87Sr/86Sr isotopic data to identify systems tracts and establish a sequence stratigraphic framework. From this integrated approach, three Turonian to Santonian sequences in the Elizabethtown core and six in the Kure Beach core are identified. The new sequences from oldest to youngest are Clubhouse II, Fort Fisher I, Fort Fisher II, Collins Creek I, Collins Creek II, Pleasant Creek I, and Pleasant Creek II. Sequences from North Carolina document significant shifts of global and regional sea-level during greenhouse conditions in the early Late Cretaceous. Maximum sea-level rise occurred globally during the early Turonian and is documented from the marine sediments of the Clubhouse II sequence. This sequence is unconformably overlain by terrestrial sediments deposited during a major fall in sea level and maximum progradation of the shoreline, as evidenced by the Fort Fisher I sequence. Global sea-level rise in the Coniacian resulted in the deposition of the Fort Fisher II sequence, which is present only in the Kure Beach core. Local marine circulation and erosion on the shelf is suggested by the absence of the Collins Creek I sequence at Kure Beach; this sequence is present only in the up-dip Elizabethtown core. Activation of a possible buried fault structure along the Cape Fear arch resulted in the formation of a regional depocenter during the late Coniacian to early Santonian and is reflected in the unusual thickness of the Collins Creek II and Pleasant Creek I sequences. The return to a more global sea-level influence occurred in the late Santonian with the deposition of the Pleasant Creek II sequence. A comparison of temporal distribution of sequences in the Elizabethtown and Kure Beach cores to corresponding sequences in New Jersey indicates significant differences in erosional and tectonic processes in the Cape Fear region during the Turonian and Santonian.

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Carpinteri, Alberto, Alessandro de Stefano, Stefano Invernizzi, Gianluca Ruocci, Giuseppe Lacidogna, Amedeo Manuello, Rosario Ceravolo, Luisa Degiovanni et Antonino Quattrone. « Experimental and Numerical Analysis of a Two-Span Model Masonry Arch Bridge Subjected to Pier Scour ». Advanced Materials Research 133-134 (octobre 2010) : 301–6. http://dx.doi.org/10.4028/www.scientific.net/amr.133-134.301.

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A scaled model of a two-span masonry arch bridge has been built in order to investigate the effect of the central pile settlement due to riverbank erosion. The bridge model has been equipped with different Non Destructive Testing (NDT) instruments and subjected to incremental settlement of the pier. The evolution of the pier scour has been investigated experimentally by means of a hydraulic model and reproduced accordingly. The numerical interpretation of damage, carried out by finite element analyses, has been compared with the results of the Acoustic Emissions (AE) monitoring. Several ultrasonic emissions have been detected and main damage source areas have been localized.

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Henderson, Penny J. « Sedimentation in an esker system influenced by bedrock topography near Kingston, Ontario ». Canadian Journal of Earth Sciences 25, n^o 7 (1 juillet 1988) : 987–99. http://dx.doi.org/10.1139/e88-098.

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Late Wisconsinan sand and gravel deposits on the Frontenac Arch, Ontario, record a major meltwater drainage system developed subglacially and subaqueously in one or more glacial lake phases of the Lake Ontario basin during retreat of the Laurentide Ice Sheet. Factors influencing channel location, morphology, and sediment deposition are ice flow direction and the Precambrian bedrock topography, in turn dependent upon bedrock structure and composition. Meltwater drainage across the Frontenac Arch is localized within a broad depression oriented approximately parallel to glacial flow. Sediment deposition within the regional depression follows ice-flow direction despite irregular bedrock relief, indicating formation of the meltwater system and associated sediments in three stages: (i) establishment of a continuous meltwater system subglacially under high hydrostatic pressure with minor erosion of underlying Precambrian bedrock; (ii) deposition of poorly sorted, coarse-grained sediment in cavities or channels associated with irregular bedrock topography; and (iii) deposition of several coalescing subaqueous outwash fans at the ice margin as the glacier receded from the area. The discontinuous nature of the deposits and the association of proximal to distal outwash fan facies within a deposit suggest that esker sedimentation occurred during periodic stabilization of the ice front during deglaciation.

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Du, Chaofei, Chuanbo Zhou, Nan Jiang et Yiwen Huang. « Structural Stability Monitoring of Model Test on Highway Tunnel with Lining Backside Voids Using Dynamic and Static Strain Testing Sensors ». Sensors 23, n^o 3 (26 janvier 2023) : 1403. http://dx.doi.org/10.3390/s23031403.

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Voids behind a lining may develop due to insufficient backfilling, poor workmanship, water erosion or gravity. They affect the interaction between the surrounding rock and lining and even cause instability of the lining structure. To ensure the safe operation of tunnels, it is very important to study the influence of voids behind the lining of the lining structure. In this paper, a laboratory model of a tunnel lining was established by taking the voids behind the lining of the Wushan Tunnel as an example. By changing the position and size of the voids, the corresponding stress variation law of the lining was obtained, and the influence of the voids behind the lining on the structural stability of the highway tunnel was analyzed. The experimental results showed that the voids behind the lining led to an increase in the stress near the voids, especially the voids at the vault. The circumferential stress and axial stress increased with increasing void depth and length, and the increase was greater with increasing void depth than increasing length; that is, the void depth had a greater effect on the lining stress. When the vault void depth was 30 mm, the axial tensile stress of the vault was 0.281 MPa, and the maximum increase was 178.2% compared with that without voids. The safety factors at different lining positions, from large to small, are: arch foot > spinner > arch top > arch waist. In the processes of lining operation and maintenance, special attention should be given to the treatment of voids behind the lining, especially deep voids.

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Lannutti, Esteban, Maria Gabriela Lenzano, Jorge Baron, Marcelo Durand et Luis Lenzano. « Análisis de los procesos de regresión y restitución del monumento natural Puente del Inca, Andes Centrales, Provincia de Mendoza, Argentina ». Andean Geology 47, n^o 2 (29 mai 2020) : 446. http://dx.doi.org/10.5027/andgeov47n2-3131.

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The Puente del Inca, next to the homonymous village, is a natural bridge located on the Cuevas River, at about 2,700 m above sea level in the Central Andes of the province of Mendoza, Argentina. Declared Provincial Natural Monument in 2005, since the beginning of the 20th century it has registered a continuous weakening, mainly related to erosive processes that cause detachments of part of the material that makes up its structure. The objective of this study is to determine the factors involved in the structural regression and restitution of the natural bridge. To achieve this, visual inspection, characterization of thermal springs, measurement of accretion-erosion rate of travertine deposits, testing of materials and the development of a structural numerical model by the Finite Element Method, were carried out. Results indicate that the deterioration is linked, mainly, with changes in the geobiological system that regulates the travertine deposition and to the heterogeneous structure of the bridge. Changes of the geobiological system are related to the activity of the thermal waters present in the area, whose discontinuity and/or fluctuations in the flow rate are influenced by both natural and anthropogenic factors. The heterogeneity of the structure conditions the stability of the monument due to the presence of a less resistant material in the lower part of the bridge arch. From the numerical simulation, safety factors between 1.5 and 3 were determined for the bridge, thus, we conclude the structure is stable against its own weight, as long as the bridge maintains the current conditions.

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Pasaribu, Parlin Hotmartua Putra. « Relationship of slope, soil type,and land use on erosion hazards ». Inovasi 19, n^o 2 (6 octobre 2022) : 147–58. http://dx.doi.org/10.33626/inovasi.v19i2.552.

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Erosi merupakan proses pengikisan tanah bagian atas yang dipengaruhi oleh berbagai faktor seperti kemiringan lereng, jenis tanah, dan tipe penggunaan lahan. Penelitian ini bertujuan untuk melihat hubungan ketiga faktor tersebut terhadap resiko bahaya erosi yang hasilnya dijadikan dasar untuk menentukan jenis praktek konservasi lahan. Data dianalisis dengan analisis korelasi Pearson. Hasil penelitian memperlihatkan bahwa faktor kemiringan lereng memiliki pengaruh yang signifikan terhadap resiko bahaya erosi dengan nilai koefisien korelasi sebesar 0,777 dan kategori hubungan sangat erat (sangat kuat) dengan arah yang positif. Sedangkan jenis tanah dan tipe penggunaan lahan tidak berpengaruh signifikan dengan koefisien korelasi yang sangat lemah (0,047 untuk jenis tanah, dan 0,129 untuk tipe penggunaan lahan). Namun, berdasarkan notasi arahnya, terdapat arah yang positif pada kedua faktor ini. Praktek konservasi yang disarankan baik dengan metode vegetatif dan mekanik berbeda untuk setiap tipe penggunaan lahan. Praktek konservasi pada penggunaan lahan permukiman yaitu penerapan saluran drainase dan tanaman penutup tanah. Praktek konservasi pada penggunaan lahan hutan sekunder yaitu pengkayaan tanaman hutan. Praktek konservasi pada penggunaan lahan belukar yaitu penghutanan kembali dan penanaman menurut kontur. Praktek konservasi pada penggunaan lahan tegalan yaitu dengan tumpang sari, pemanfaatan mulsa, penanaman sejajar kontur, teras gulud, dan saluran pengelak. Beberapa bentuk praktek konservasi tersebut berguna bagi berbagai pihak dalam melakukan pengelolaan dan pelestarian sumberdaya lahan. Kata Kunci : Erosi, faktor erosi, bahaya erosi, praktek konservasi, pelestarian sumberdaya lahan.

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Hasan, Ahmed Abbas. « Geomorphological Landscapes of Tar Al-Sayed and Tar Al-Najaf Area-Central of Iraq ». JOURNAL OF UNIVERSITY OF BABYLON for Pure and Applied Sciences 26, n^o 10 (23 décembre 2018) : 197–212. http://dx.doi.org/10.29196/jubpas.v26i10.1856.

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Iraq has a variety of geomorphological landscapes, because of the varied and beautiful desert landforms and these forms may tell us the tectonic history on a long term and also the climate of this part of the Arabian plate. Tar Al-Sayed and Tar Al-Najaf area have geomorphological landscapes that are variable and reflect different exogenic processes and these features been observed in the field are: Barchans and sand sheet which are mobile features, and they are widespread, but the smallest Geomorphological Landscapes are wind ripples, other features are Mesas and escarpments as a result of the erosion of sequences of sedimentary rocks. Also, butte these are flattened top hills, Zeugen obvious feature in the study area found in soft strata been eroded by the wind. In the areas where the wind erosion predominates over water erosion in moulding some of these features. Yardangs are wind- roded, aerodynamic hills. Tafoni Caves are arch-shaped entrances sized several centimeters to several meters in diameter and depth. When weathering together with mass collapse found, then Natural Arches formed. They most commonly occur in sandstone and claystone. Slope Instability which it is extensively landslide phenomena. The Drainage Systems in the study area have dendritic pattern and it is the most predominant. Some of the features composed of fluvial sediments as in Alluvial Fans.

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Garrocho-Rangel, J. Arturo, Juana M. Arvizu-Rivera, Nadia P. Campos-Lara, Miguel A. Rosales-Berber et Amaury Pozos-Guillén. « Esophageal Atresia with Tracheoesophageal Fistula and Gastroesophageal Reflux in Children : Dental Considerations and Case Report ». Journal of Clinical Pediatric Dentistry 42, n^o 4 (1 juillet 2018) : 256–61. http://dx.doi.org/10.17796/1053-4628-42.4.3.

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Background: Esophageal Atresia (EA) is defined as the congenital interruption of the continuity of the esophagus. Pediatric patients also have other congenital conditions, such as Tracheo-Esophageal Fistula (TEF). Case report: A 7-year-old male with TEF referred by a Pediatric Cardiologist, with the principal complaint of “severe and generalized tooth wearing”. Considering that the patient was systemically stable, it was decided to perform the oral procedures under local anesthesia and rubber-dam isolation with an antimicrobial prophylaxis regimen. The treatment consisted of the extraction of all maxillary primary incisors and canines and both first molars; in the mandibular arch, only the lower second right molar was extracted, and a distal shoe was placed. Pulpotomies were performed and preformed metallic crowns were placed on the remaining second primary molars, on both lower first molars, and on lower canines and lateral incisors. Finally, a fixed prosthesis was positioned in the upper arch, and cemented through orthodontic bands adapted to both crowned second molars. The patient has been maintained under close medical and dental control. The child showed satisfactory oral conditions, and the vomiting episodes had decreased significantly. Conclusions: Dentists can learn and then participate in the integral health management of infants and young children affected with EA/TEF, particularly those with dental erosion.

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Lim, Iu Tong, Avatar Singh Mohan Singh, Viji Ramasamy, Suhana Abdul Rahim, Piao Piao Ang et Irfan Mohamad. « Paediatric Extensive Cervical Plexiform Neurofibroma Mimicking a Parotid Lesion ». Malaysian Journal of Paediatrics and Child Health 26, n^o 2 (2 décembre 2020) : 60–67. http://dx.doi.org/10.51407/mjpch.v26i2.102.

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Neurofibromatosis Type 1 (NF1), also known as von Recklinghausen’s disease is a multisystem genetic disorder that occurs with an incidence of 1 in 4000 live births. Plexiform nmeurofibroma (PN) is a rare important variant of NF1, seen in 5 to 15% of cases. We report a 7-year-old boy, without family history of neurofibromatosis presented with left neck swelling associated with multiple café au lait spots for one-year duration. Computed tomography of head and neck revealed an extensive soft tissue lesion involving the left parapharyngeal, carotid space and parotid space encasing the left internal and common carotid artery until its origin at the arch of aorta with erosion of the basiocciput. He underwent transcervical excision of the lesion, which was confirmed histopathologically as PN.

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Bitner, A. K., D. O. Gafurov, O. M. Gafurov, N. V. Myshevskiy, E. V. Temenyova, A. O. Gafurov et A. V. Samkov. « HYDROCARBON PROSPECTS OF THE CHULAKANSKAYA AREA IN THE KRANOYARSK TERRITORY ACCORDING TO GEOCHEMICAL DATA ». Geology and mineral resources of Siberia, n^o 1 (mars 2022) : 26–35. http://dx.doi.org/10.20403/2078-0575-2022-1-26-35.

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Soil vapor survey o soil deposits exposed by erosion has been carried out on the Chulakanskaya area. The areal migration arch-like anomalous zone coinciding with the Chulakan uplift and the semicircular zone around the East Chulakan uplift have been mapped. The field of increased helium concentrations reflects elem of deep fault tectonics. The deposits prediction was conducted on the basis of the neural network modeling by the mathematical apparatus technique; the forecast is correlated with specified uplifts. The presence of the hydrocarbon migration shows on the Chulakanskaya area and the results of statistical processing of geochemical data indicate the possible existence of gas condensate accumulations with oil rims similar to the Sobinskoye one. The area is recommended for exploratory drilling.

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Malena, Marialaura, Maurizio Angelillo, Antonio Fortunato, Gianmarco de Felice et Ida Mascolo. « Arch bridges subject to pier settlements : continuous vs. piecewise rigid displacement methods ». Meccanica 56, n^o 10 (5 juillet 2021) : 2487–505. http://dx.doi.org/10.1007/s11012-021-01397-1.

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AbstractSettlements severely affect historic masonry arch bridges worldwide. There are countless examples of structural dislocations and ruins in recent years due to severe settlements at the base of pier foundations, often caused by shipworm infestation of wooden foundations or scouring and riverbed erosion phenomena. The present paper proposes an original way to approach the failure analysis of settled masonry arch bridges. The proposed method combines two different 2D numerical models for the prediction of masonry arch bridge capacity against settlements and for safety assessment. The first one is the Piecewise Rigid Displacement method, i.e. a block-based limit analysis approach using the well known Heyman's hypotheses; the second one is a continuous Finite Element approach. The case study of the four-span Deba Bridge (Spain, 2018) failure is presented with the aim to illustrate how the methods work. The failure analysis produced satisfactory results by applying both methods separately, in confirmation of their reliability. Their combination also allowed to obtain a significantly reduction in computational cost and an improvement of prediction accuracy. A sensitivity and a path-following analysis were also performed with the aim to demonstrate the robustness of the presented method. The obtained simulations highlighted that the results do not depend on the friction angle and that a proper prediction of the evolution of the structural behavior can be obtained only taking into account geometric nonlinearities. Such results demonstrate once again that in settled masonry arches geometry prevails over the mechanical parameters. The current study paves the way for the fruitful use of the proposed approaches for a wider range of applications, as, for example, the mechanism identification or the displacement capacity assessment of masonry structures under overloading as seismic loads.

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Sharma, Rakesh Sharma, et Sunil Kumar. « Pattern of ossicular chain involvement in chronic suppurative otitis media ». Asian Journal of Medical Sciences 13, n^o 7 (1 juillet 2022) : 132–37. http://dx.doi.org/10.3126/ajms.v13i7.43536.

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Background: Chronic suppurative otitis media has been acknowledged as a conspicuous pathology affecting the middle ear since times immemorial. Aims and Objectives: The aim of the study was to study the incidence of ossicular involvement and various patterns of its presentation in chronic suppurative otitis media. Materials and Methods: With the objective to study the incidence and pattern of ossicular involvement in chronic suppurative otitis media and also to correlate the various ossicular defects with the type and extent of the disease, we decided to take up this study at our institute. The study involved a total of 100 patients between February 2020 and June 2021. Results: Among the 100 patients included in this study, there were 56 males and 44 females. Among the 100 patients in this study, there were 54 tubotympanic and 46 atticoantral chronic suppurative otitis media patients. Among the tubotympanic cases, ossicular involvement was discovered in 18 cases while 36 cases were without any ossicular involvement. Among the atticoantral cases, 38 cases had ossicular involvement while eight cases had no ossicular disruption. Out of the 56 cases that showed ossicular involvement, incus was involved in 52 cases, malleus was involved in 14 cases, and stapes was involved in 10 cases. Conclusion: Ossicular involvement was seen in 53% of the operated cases of chronic suppurative otitis media. Atticoantral disease is 3 times more prone to having ossicular erosion than tubotympanic disease. Wet ears have 6 times more likelihood of having ossicular involvement in comparison to dry ears. Incus is the most common ossicle involved followed by malleus and stapes. Erosion of the incudal long process is the most common abnormality. Incus is invariably involved in atticoantral disease. Stapes involvement in the form of resorption of the arch of stapes is the most common pattern. An eroded long process along with stapes arch resorption is the most frequent ossicular chain defect.

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Wood, Barry G. M. « Rethinking post-Hercynian basin development : Eastern Mediterranean Region ». GeoArabia 20, n^o 3 (1 juillet 2015) : 175–224. http://dx.doi.org/10.2113/geoarabia2003175.

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ABSTRACT The geological community has broadly accepted that the region of NE Africa and NW Arabia deformed under tension during the post-Hercynian disintegration of northern Gondwana. Further, it has also generally accepted that sedimentation occurred within extensional half-grabens that formed along the length of what was then the southern margin of the Neo-Tethys Ocean. Consensus is that Alpine age compression then forced inversion of these half-grabens to form the well-known Syrian Arc structures that stretch from the Western Desert of Egypt to NE Syria. As new data has become available (Enclosures I and II), there are indications that an alternative mechanism, founded in continuous compression rather than extension then compression, better explains the tectonics and sedimentary history of the region since the late Palaeozoic. Data from Syria, Jordan, the Levant and Egypt demonstrate that distinct post-Hercynian Orogeny, Tethyan and Alpine sequences (basins) lie on a final, deeply eroded and folded Hercynian Unconformity, and that this surface refolded post-Hercynian time to form the confining walls of a single trough extending from NE Syria to the Western Desert of Egypt. Prior to the deposition of the first Tethyan basin in the late Carboniferous, the Hercynian Unconformity surface deformed to establish a plate-scale arch, the Levant Arch, that extended from NE Syria and southern Turkey, over 1,500 km southwest to the three corners region of Egypt, Sudan and Libya. This arch refolded in the late Palaeozoic to form the early Levant Trough composed of the Palmyride Trough, its extension under the Eastern Mediterranean and the Levant, through the Sinai and into western Egypt. Contrary to the now established idea that the southern margin of the Carboniferous–Permian Tethyan Ocean was a “passive margin”, the trough and internally constrained basins, slowly narrowed and deepened under continuous compression from the southeast from at least the late Palaeozoic to the Present. Each internal, distinct basin sequence is well defined by long periods of slow, low-energy, laterally persistent, sedimentation, separated from underlying and overlying basin sequences by almost equally long periods of erosion or non-deposition, coincident with increased regional structuring and volcanism. Each new basin, following a cessation of this regional structural activity, found itself nested within its predecessor, with the older basin lying slightly counter-clockwise to the younger. It is proposed that counter-clockwise, regional (and basin) rotation was facilitated by newly documented NW-oriented cross-shears, with inter-basin periods of erosion or non-deposition due to whole-basin (regional) uplift, forced by trough narrowing. Tectonic-scale geologic features, such as cross-basin and regional shears, trough margin uplift and northwest migration, laterally extensive, sheet-like sedimentation, sediment feathering onto unfaulted margins, regional erosion related to whole-basin uplift and massive flank gravity sliding with resultant down-slope buckle folding, taken together, attest to compression as the driving agent. Whole-basin and regional, counter-clockwise rotation through time, suggests a constant direction of compression. Understanding the correlation of sedimentary fill to local and regional structural events brings new insight to the deformation of the northern regions of Gondwana during the closure of Tethyan oceans. This model may also apply on a larger scale of whole-plate deformation.

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Remus, David, et Karen Tindale. « THE PLEASANT CREEK ARCH, ADAVALE BASIN, A MID DEVONIAN TO MID CARBONIFEROUS THRUST SYSTEM ». APPEA Journal 28, n^o 1 (1988) : 208. http://dx.doi.org/10.1071/aj87017.

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Interpretation of recently acquired multifold seismic data has led to a reappraisal of the structural evolution of the Adavale Basin with particular reference to the Pleasant Creek Arch.The Basin initially formed as a back arc basin to the west of the Anakie/Nebine volcanic arc. Three stages of tectonic evolution are recognised; rifting, extension and convergence. The Pleasant Creek Arch represents a foreland fold belt cratonward of the major convergent margin deformational zone.The model proposed for the development of the Pleasant Creek Arch is a buried to weakly emergent foreland thrust system modified by Late Carboniferous erosion. This was subsequently covered by sediments of the Galilee and Eromanga Basins. Late to Middle Devonian sediments are involved in thrusting that exhibits two styles of deformation. Along the southern 70 km of the thrust front Lower to Middle Devonian sediments are thrust under an upper decollement forming a passive roof duplex or backthrust zone. The Boree Salt acts as this upper decollement. The thrust tipline is controlled by the western depositional edge of the salt. North of this area the thrust appears to have been weakly emergent. Proprietary and open file seismic data from ATP's 301P, 304P and 305P and surrounding permits are used to illustrate the model. Comparisons can be made between this model and similar thrust systems in the Canadian Rocky and Mackenzie Mountains, the Appalachian Plateau, the Southern Norwegian Caledonides, the Kirthar and Sulaiman Mountain ranges of Pakistan and the Papua New Guinea fold belt.

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Liu, Lin, Yao Rong, Cheng Ke Zhang, Meng Yun Mao et Lu Lin Zhang. « Instability Mechanism of Du Yun Pass Tunnel Entrance Weathered Stacking Area Analysis ». Applied Mechanics and Materials 858 (novembre 2016) : 81–85. http://dx.doi.org/10.4028/www.scientific.net/amm.858.81.

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The stability of the tunnel portal section under poor terrain and geological condition has always been the focus of construction safety. The stability problem has become more complex for the erosion accumulation area under the valley. In this paper, firstly the stability of the tunnel portal is classified. Combined with engineering cases, the FEM numerical method is used to simulate the supporting structure and construction process of the tunnel. Based on the distribution of the plastic zone and displacement of surrounding rock, the mechanism of the instability of the tunnel portal is analyzed. Through the optimized construction scheme that arranges pile foundation in tunnel arch foundation, the bearing capacity of foundation has been greatly improved, which has effectively prevented the instability of surrounding rock caused by the slope deformation and foundation settlement. The conclusions that have been drawn in this paper can be used for reference for related projects.

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Thi Phuong Chi, Hoang, Ha Quang Hai et Nguyen Thi Que Nam. « Geotourism Potential Of Phu Quy Island, Binh Thuan Province ». Science and Technology Development Journal - Natural Sciences 4, n^o 1 (21 décembre 2020) : first. http://dx.doi.org/10.32508/stdjns.v4i1.997.

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Phu Quy island – Binh Thuan province, is 120 km southeast of Phan Thiet city, where the long – lasting destruction of waves, wind, and rain into oceanic volcanic materials formed four significant geomorphological heritages. These geomorphosites have scientific and additional values (cultural, aesthetic, and ecological values), of which mountain Cao Cat cinder cones deserves to be a South Central Coast geomorphosite; while mountain Cam volcano, Hang Cliff – Nho beach erosion coast and Tranh volcanic islet are proposed at a local level. The impressive cliffs exposed layers of coarse and steeply sloping sediments caused by blasting; erosion coastal terrain such as cliffs, rocky headlands, stacks, arch, islets, etc. all shapes and colors associated with landmarks such as Mong Tay tack, Gam inlet, Ban inlet, Xuong Ca headland, Phat inlet, Dried Squid pond, Den islet, Giua islet, Do islet... are outstanding scientific values. Furthermore, Sa Huynh cultural relics (2,500 – 3,000 years ago) discovered in mountain Cao Cat; Linh Son, and Linh Buu ancient pagodas; Phu Quy landscape viewpoints from mountain Cam Lighthouse or colorful coral reefs on Tranh islet... are additional values that increase the worth of Phu Quy island's geomorphosites. Interpreting the scientific and additional values of these geomorphosite with images, books, geometrically similar models, etc. would promote the geotourism – a niche of the sustainable tourism market that is developed along with Global Geoparks recognized by UNESCO.

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Montanini, Roberto, Michele Scafidi, Giorgio Staiti, Antonia Marcianò, Leonardo D’Acquisto et Giacomo Oteri. « Misfit evaluation of dental implant-supported metal frameworks manufactured with different techniques : Photoelastic and strain gauge measurements ». Proceedings of the Institution of Mechanical Engineers, Part H : Journal of Engineering in Medicine 230, n^o 12 (11 novembre 2016) : 1106–16. http://dx.doi.org/10.1177/0954411916676192.

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This study aims to compare in-vitro the fitting accuracy of implant-supported metal frameworks used for full-arch orthodontic restoration. The hypotheses tested were as follows: (1) for a fixed implant morphology, strains developed within the framework depend on how the framework had been fabricated and (2) stresses transferred to the implant–bone interface are related to the amount of framework misfit. Metal frameworks were fabricated using four different manufacturing techniques: conventional lost-wax casting, resin cement luting, electrospark erosion, and computer-aided design/computer-aided manufacturing milling. Each framework was instrumented with three strain gauges to measure strains developed because of prosthetic misfit, while quantitative photoelastic analysis was used to assess the effect of misfit at the implant–resin interface. All the tested frameworks presented stress polarization around the fixtures. After screw tightening, significantly greater strains were observed in the lost-wax superstructure, while the lowest strains were observed in the luted framework, demonstrating consistent adaptation and passive fitting. No significant difference in stress distribution and marginal fit was found for bars fabricated by either computer-aided design/computer-aided manufacturing or spark erosion. This study suggested that, in spite of known limitations of in-vitro testing, direct luting of mesostructures and abutments should be the first clinical option for the treatment of complete edentulism, ensuring consistent passive fitting and effective cost–benefit ratio.

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Latimba, Yusran, Ahmad Syarif Sukri, Tryantini Sundi Putri et Muriadin Muriadin. « PERAMALAN TINGGI DAN PERIODE GELOMBANG PADA PANTAI TINOBU LASOLO KONAWE UTARA ». STABILITA || Jurnal Ilmiah Teknik Sipil 8, n^o 2 (23 août 2020) : 59. http://dx.doi.org/10.55679/jts.v8i2.13680.

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ABSTRAKPantai Tinobu telah terjadi permasalahan seperti erosi pantai, erosi tersebut dapat terjadi secara alami atau karena adanya aktifitas manusia. Pantai Tinobu mengalami endapan yang dapat mengakibatkan majunya garis pantai, pendangkalan muara sungai yang menyebabkan aliran sungai dapat memimbulkan banjir.Tujuan penelitian ini adalah mengetahui tinggi gelombang pada peramalan gelombang pantai Tinobu dengan mengkonversi data angin dan mengetahui bentuk penjalaran gelombang di pantai Tinobu dengan model simulasi CG WAVE pada SMS 10.0.10 di pantai Tinobu. Metode penelitian menggunakan analisis dan survey pasang surut,, topografi dan bathimetri.Hasil dari penelitian ini adalah tinggi gelombang dan periode gelombang signifikan maksimum di laut dalam dari arah timur adalah 0,81 meter dan 3,26 detik. Pada penelitian ini penjalaran gelombang yang disimulasikan adalah penjalaran pada arah Timur dengan sudut datang pada model isian 90 derajat. Kemudian dari arah datang angin ini saya mengambil periode 3,26 detik dengan menyamakannya pada kondisi peramalan gelombang pada hasil analisa perhitungan kala ulang periode dengan 25 tahun. Kata Kunci : Gelombang, Water Modeling, Pantai.ABSTRACTTinobu Beach problems have occurred such as coastal erosion, erosion can occur naturally or due to human activities. Tinobu beach has deposited which can cause coastline advancement, silting of river mouths which causes river flow can cause flooding. The purpose of this study was to determine the wave height in the forecasting of Tinobu beach waves by converting wind data. and bathymetry. The results of this study are the wave height and the maximum significant wave period in the deep sea from the east is 0.81 meters and 3.26 seconds. In this study the wave propagation that I simulate is propagation in the East direction with the angle of incidence in the 90-degree field model . Then from the direction of this angina I took a period of 3.26 seconds by equating it to the wave forecasting conditions on the results of the analysis of the recalculation period with a period of 25 years. Keywords : Waves, Water Modeling, Beaches

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Vender, John R., Steven J. Harrison et Dennis E. McDonnell. « Fusion and instrumentation at C1–3 via the high anterior cervical approach ». Journal of Neurosurgery : Spine 92, n^o 1 (janvier 2000) : 24–29. http://dx.doi.org/10.3171/spi.2000.92.1.0024.

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Object. The high anterior cervical, retropharyngeal approach to the anterior foramen magnum and upper cervical spine is a favorable alternative to the transoral and posterolateral approaches, which both cause instability of the craniovertebral junction. Previously, such instability was corrected via an occipitocervical fusion during a separate surgical procedure. Methods. Seven patients requiring C-2 corpectomy (foramen magnum meningioma [two patients], critical stenosis secondary to rheumatoid arthritis [two patients], C-2 fracture [two patients], and stenosis secondary to Rickets [one patient]) are presented. All patients underwent C1–3 fusion followed by instrumentation with a Caspar plate. A solid fusion was achieved in six patients. One patient experienced erosion of the anterior arch of C-1 requiring posterior stabilization. Conclusions. Fusion and instrumentation at C1–3 can be performed safely and with minimal increase in surgical time. In selected patients, this may eliminate the need for an additional posterior procedure and maintain occipital—C1 mobility.

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Menezes, Arnold H., John C. VanGilder, Charles R. Clark et George El-Khoury. « Odontoid upward migration in rheumatoid arthritis ». Journal of Neurosurgery 63, n^o 4 (octobre 1985) : 500–509. http://dx.doi.org/10.3171/jns.1985.63.4.0500.

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✓ Lack of correlation between the severity of rheumatoid subluxation of the upper cervical vertebrae and supposed absence of neurological damage has led to the erroneous supposition that this finding is innocuous. Incomplete autopsy studies in rheumatoid arthritis have failed to recognize the cause of death, despite previously proven dramatic occipito-atlanto-axial dislocations. The most feared entity of rheumatoid basilar invagination, namely “cranial settling,” is poorly understood. Between 1978 and 1984, the authors treated 45 rheumatoid arthritis patients who were symptomatic with “cranial settling.” This consisted of vertical odontoid penetration through the foramen magnum (9 to 33 mm), occipito-atlanto-axial dislocation, lateral atlantal mass erosion, downward telescoping of the anterior arch of C-1 on the axis, and rostral rotation of the posterior arch of C-1 producing ventral and dorsal cervicomedullary junction compromise. Cervicomedullary junction dysfunction has mistakenly been called “entrapment neuropathy,” “progression of disease,” or “vasculitis.” Occipital pain occurred in all 45 patients, myelopathy in 36, blackout spells in 24, brain-stem signs in 17, and lower cranial nerve palsies in 10. Four patients had prior tracheostomies. Four previously asymptomatic patients with “cranial settling” presented acutely quadriplegic. The factors governing treatment were reducibility and direction of encroachment determined by skeletal traction and myelotomography. Transoral odontoidectomy was performed in seven patients with irreducible pathology. All patients underwent occipitocervical bone fusion (with C-1 decompression if needed) and acrylic fixation. Improvement occurred during traction, implying that compression might be the etiology for the neurological signs. There were no complications. Thus, “cranial settling” is a frequent complication of rheumatoid arthritis; although it is poorly recognized, it has serious implications and is treatable.

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Carrel, Thierry, Martin Czerny et David Reineke. « Huge Ruptured and Infected Pseudoaneurysm of the Ascending Aorta and Aortic Arch With Erosion of Sternum After Previous Cardiac Surgery ». Seminars in Thoracic and Cardiovascular Surgery 24, n^o 3 (septembre 2012) : 229–31. http://dx.doi.org/10.1053/j.semtcvs.2012.09.001.

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Nikmah, Karimatun, et Nusa Muktiadji. « Valuasi Kinerja Keuangan Dan Kinerja Saham (Studi Kasus PT Multistrada Arah Sarana Tbk). » Jurnal Ilmiah Manajemen Kesatuan 7, n^o 2 (14 novembre 2019) : 247–58. http://dx.doi.org/10.37641/jimkes.v7i2.227.

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This study aims to determine the effect of the company's financial performance on the company's stock performance. Based on the results of research, discussion and analysis conducted, it is known that overall company performance is affected by major problems namely due to slowing global economic conditions, oversupply of Chinese tires, weakening of the world currency against the USD and falling commodity prices of rubber being a factor decrease in sales volume and affect the amount of net profit generated by the company. Inefficiency in suppressing cost of goods sold and operating expenses also causes the erosion of operating profits generated by the company. So that it affects the financial performance and overall stock performance which also impacts the decline in the value of the company.

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Gimaletdinova, A. M., G. T. Saleeva, N. V. Boychuk, V. A. Abdul’yanov et R. A. Saleev. « Histologic investigation of cytotoxicity of nanocomposite particles used for direct restorations in dentistry in rat models ». Kazan medical journal 98, n^o 5 (15 octobre 2017) : 747–52. http://dx.doi.org/10.17750/kmj2017-747.

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Aim. To study cytotoxicity of glass-ionomer cement 3MTMESPETMVitremer, nanocomposite for direct restorations 3MTMESPETMFiltekTMUltimate and nanocomposite particles 3MTMESPETMFiltekTMUltimate in the experiment with laboratory male Wistar rats. Methods. The experimental animals in precervical region of the first left superior molar had a cavity formed with the use of dental drill, which was filled with glass-ionomer cement 3MTMESPETMVitremer, nanocomposite for direct restorations 3MTMESPETMFiltekTMUltimate or nanocomposite particles 3MTMESPETMFiltekTMUltimate. On day 14 the animals were removed from the experiment, and sample of gingiva adjucent to the formed tooth cavity and sample of gingiva from the opposite side of dental arch were taken. Paraffin sections of the samples were prepared and were straightaway placed on a glass slide. For histologic study deparaffinized sections were stained with hematoxylin and eosin and immunohistochemical test with the use of primary antibodies to macrophage marker CD68, marker of cell proliferative activity Ki-67, mesenchymal marker vimentin, endothelial cell membrane antigen CD34 and cytokeratin CKP-PAN. Results. The results proving cytotoxic effect of nanocomposite particles 3MTMESPETMFiltekTMUltimate on the tissues surrounding teeth, were received. On the operated and contralateral sides morphologic changes of mucosa were found including the signs of inflammation, hyperkeratosis, and cell proliferative activity. Changes of gingival mucosa are mostly pronounced in animals whose tooth cavity was filled with nanocomposite particles. Conclusion. Taking into account the negative effect of nanocomposite particles discharging at erosion on gingival mucosa, we consider it reasonable to limit the use of the studied materials on occlusal surfaces exposed to heavy mechanical load leading to intensive erosion.

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Heron, Daniel Le, Owen Sutcliffe, Khalid Bourgig, Jonathan Craig, Claudio Visentin et Robert Whittington. « Sedimentary architecture of Upper Ordovician tunnel valleys, Gargaf Arch, Libya : Implications for the genesis of a hydrocarbon reservoir ». GeoArabia 9, n^o 2 (1 avril 2004) : 137–60. http://dx.doi.org/10.2113/geoarabia0902137.

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ABSTRACT In the Murzuq Basin, southwest Libya, as elsewhere in North Africa, Upper Ordovician glaciogenic rocks represent an important hydrocarbon reservoir. In this basin, anastomosing, potentially sand-filled palaeovalley networks within the Upper Ordovician succession have been described from seismic data that provide promising prospects for exploration. However, little is known about the origin and architecture of the palaeovalley-fills. On the Gargaf Arch, an outcrop analogue for these structures occurs and is comparable in scale to the valley networks described in the subsurface. This palaeovalley system is 30 km long with two 4 km-wide tributaries, cut into ice-distal glaciomarine mudrocks and diamictites and filled with ice-proximal sandstones and subordinate shales. It was created by subglacial meltwater erosion and glacial loading of a soft substrate during ice sheet advance. The initial stage of valley-fill involved the deposition of coarse-grained sands and conglomeratic ice-proximal, submarine outwash, as localised mass flows. The main stage of fill was characterised by axially (northerly) prograding, underflow-dominated fan lobes deposited in water depths of up to 80 m. A comparison with coeval valley systems in Mauritania, Algeria, Saudi Arabia and Jordan is provided that highlights the variable regional character of palaeovalley-fills and the influence that water-depth had on architecture.

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Lai, Jin Xing, Xiao Wei Liu et Fei Zhou. « Long-Term Safety Analysis of Tunnel Structure Based on the Performing Degree of Support Strength ». Advanced Materials Research 261-263 (mai 2011) : 1220–24. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.1220.

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At present, the new Austrian tunneling method is basically used as the theoretical guidance for domestic tunnel design, which shows that the primary support is not progressed by durability design in the light of service life in the practical work generally acting as the temporary support structure during the period of construction. After the long-term tunnel operation, owing to the erosion of groundwater and the changes of internal stress and external load of surrounding rock, the reinforced of primary support system will be rusted; the bolt, grille arch frame and I-beam will be partially invalidated; the stress of tunnel structure system will be readjusted gradually from the original load-bearing state with dominant position of primary support into the load-bearing state by secondary lining. The Long-term safety analysis refers to the analysis of secondary lining internal force and safety coefficient by load structure model, and the long-term safety analysis of Qingshashan tunnel which is in season frozen zone with complex geological conditions is very necessary.

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Latypova, M. R., O. V. Khotylev, N. S. Balushkina, A. G. Kalmykov, G. A. Kalmykov, L. F. Kopaevich, E. V. Karpova et V. V. Churkina. « Sedimentary conditions of the Abalak formation and Vogulkinskaya strata on the area of Kamennaya summit (Krasnoleninsky arch, Western Siberia) ». Moscow University Bulletin. Series 4. Geology 1, n^o 6 (29 janvier 2022) : 49–60. http://dx.doi.org/10.33623/0579-9406-2021-6-49-60.

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As part of this work, various sedimentation environments were identified in the Middle-Late Jurassic (J2k–J3v1) on the territory of the Krasnoleninsky arch in Western Siberia. The heterogeneity of the seabed topography and the presence of islands formed by protrusions of the pre-Jurassic basement led to the formation of the Vogulka strata as a result of the removal of clastic material from the land. At the same time, far from the islands, in relatively calm shallow environments, clayey and glauconite-clayey sediments of the Abalak Formation accumulated. Gravelites and sandstones of the Vogulka strata were formed unevenly. The greatest thickness of these deposits is observed to the west of the central upland. The difference in the thickness of clastic strata on the western and eastern slopes could probably be caused by the specific horseshoe shape of the island and the absence of active currents on the western part of the slope, as well as its greater steepness. The upper member of the Vogulka strata, composed of detrital limestones, is extremely thin (no more than 1 m), and contains numerous unconformities. Probably, these traces of erosion can be indirect evidence of the influence of the Late Oxford regression on the structure of the section, which was previously noted in adjacent territories.

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Thiel, G., RP Mills et N. Mills. « Factors affecting hearing improvement following successful repair of the tympanic membrane ». Journal of Laryngology & ; Otology 127, n^o 4 (25 février 2013) : 349–53. http://dx.doi.org/10.1017/s0022215113000157.

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AbstractBackground:The main aim of tympanic membrane repair is the elimination of chronic or intermittent aural discharge. Hearing improvement may or may not occur following a technically successful operation.Method:This study entailed a retrospective analysis of prospectively collected data from 203 operations that resulted in an intact tympanic membrane 6 months after surgery.Results:Complete hearing data were available for 169 operations on 160 patients. Of these, 53 per cent resulted in closure of the air–bone gap to within 10 dB, and 54 per cent of cases had post-operative hearing thresholds of at least 30 dB. The mean hearing change after surgery was +8.3 dB. Multiple regression analysis indicated that hearing improvement was more likely in large compared with small perforations. Smaller hearing gains occurred in ears with erosion of the stapes arch and/or fixation of the stapes, as well as in those with active discharge at the time of surgery and in revision cases.Conclusion:Greater hearing improvement can be expected following successful repair of perforations involving more than 50 per cent of the drum area. Poorer results are likely to occur in ears with additional middle-ear pathology and in revision cases.

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Silantiev, Vladimir V., Marat F. Validov, Dinara N. Miftakhutdinova, Vladimir P. Morozov, Bulat G. Ganiev, Azat A. Lutfullin, Kirill D. Shumatbaev et al. « Sedimentation model of the middle Devonian clastic succession of the South Tatar Arch, Pashyian Regional stage, Volga-Ural Oil and Gas Province, Russia ». Georesursy 24, n^o 4 (20 décembre 2022) : 12–39. http://dx.doi.org/10.18599/grs.2022.4.2.

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The Pashyian Regional stage (horizon) is the main productive unit of the middle Devonian clastic succession of the South Tatar arch. This article presents, for the first time, maps of the lower and upper parts of the Pashyian, including data on sand-shale ratio, number of sand layers (reservoirs) and thickness, based on the analysis of logging data from 25,000 wells. The maps were created by spatial interpolation of Natural Neighbor and ArcGIS Pro software. The model of sedimentation of the Pashyian Regional stage reflects the interpretation of the plotted maps as well as the synthesis of the results of detailed core investigations (lithological, sedimentological, ichnotextural, petrophysical, etc.) and analysis of archive and published materials. The main points of the proposed model are as follows. The Pashyian sediments were formed in a marine basin, in an environment comparable to that of the middle shelf of modern seas – in an offshore zone dominated by current activity. The basin floor was a relatively flat plateau, on which sandy, silty and clay sediments were simultaneously accumulated. Sediments of all types accumulated during sea transgression. Sea regression caused erosion and destruction of the already formed sediments. Positive landforms of seabed relief, composed predominantly of sandy well-sorted material, comprised autochthonous underwater sand bars, formed by constant currents parallel to the bathymetric contour of the seabed. Underwater sand bars formed extensive systems nearly throughout the entire territory of the modern South Tatar arch. At the same time, allochthonous, poorly sorted, less mature sediments were formed in underwater troughs produced by transversal currents (directed from the shore towards the sea). The proposed model explains the consistent thickness of the Pashyian Regional stage, the mosaic distribution of sand bodies over the area, and the lens-like shape of the sand and siltstone reservoirs. The model can be extrapolated to other stratigraphic intervals of the Devonian clastic succession with similar sedimentological features.

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Azizipour, Mohamad, Farshid Amirsalari Meymani et Mohammad Mahmoodian Shooshtari. « Enhancing scour protection in river bends : a novel slotted bank-attached vane ». Water Supply 20, n^o 6 (1 juin 2020) : 2175–84. http://dx.doi.org/10.2166/ws.2020.116.

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Abstract One of the most effective approaches for bank control erosion is using bank-attached vanes. In spite of the superiority of the bank-attached vanes to spur dikes, the vanes' tips are still vulnerable to local scour caused by flow–structure interaction. In this study, slotted bank-attached vanes are proposed to reduce local scour at the tip of the triangular submerged vane. For this, a rectangular slot is created parallel to the chord of the vane with an area of ten percent of the effective area of the vane surface. Two types of conventional vanes and slotted vanes were installed at different angles of attack of 23, 30, 40 and 60 degrees in an arch flume. Experiments were carried out in clear water conditions with different flow regimes with Froude numbers of Fr = 0.287, 0.304 and 0.322. The results show that the slotted vane outperforms the conventional vane by reducing maximum scour depth by about 70, 20, 17 and 54 percent for different angles of attack of 23, 30, 40 and 60 degrees, respectively. The proposed slotted vane also resulted in reduction of scour hole volume around the vane and formed the scour hole away from the outer bank.

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Lowry, David W., Ian F. Pollack, Brent Clyde, A. Leland Albright et P. David Adelson. « Upper cervical spine fusion in the pediatric population ». Neurosurgical Focus 3, n^o 3 (septembre 1997) : E1. http://dx.doi.org/10.3171/foc.1997.3.3.1.

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The outcomes of 25 pediatric patients who underwent upper cervical or occipitocervical fusion at the authors' institution since 1983 were reviewed. At a mean age of 9 years, the patients presented with spinal instability that was associated with os odontoideum in 11 cases, rotatory subluxation in five cases, odontoid fracture in two cases, atlantooccipital dislocation in two cases, and congenital atlantoaxial instability in five patients, four of whom had Down's syndrome (trisomy 21). Ten children had abnormal findings on neurological examination preoperatively; however, nine experienced improvement or resolution of deficits as of their latest follow-up evaluation (mean 17 months). Fusion was achieved with the first operation in 21 of 25 patients; eventually it was attained in all but one. Four patients exhibited persistent spinal instability after an initial procedure. This was caused by erosion of a multistranded cable through the intact arch of C-2 in two cases, by pin site infection necessitating early halo removal in one case, and by slippage in a halo following a Gallie procedure, which was revised with a Brooks fusion in one case. This series, the largest yet published, shows that with appropriate surgical management, posterior upper cervical fusion in the pediatric population is highly successful. Careful attention to halo pin site care and caution in using multistranded cable in young patients may improve results.

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Lowry, David W., Ian F. Pollack, Brent Clyde, A. Leland Albright et P. David Adelson. « Upper cervical spine fusion in the pediatric population ». Journal of Neurosurgery 87, n^o 5 (novembre 1997) : 671–76. http://dx.doi.org/10.3171/jns.1997.87.5.0671.

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✓ The outcomes of 25 pediatric patients who underwent upper cervical or occipitocervical fusion at the authors' institution since 1983 were reviewed. At a mean age of 9 years, the patients presented with spinal instability that was associated with os odontoideum in 11 cases, rotatory subluxation in five cases, odontoid fracture in two cases, atlantooccipital dislocation in two cases, and congenital atlantoaxial instability in five patients, four of whom had Down's syndrome (trisomy 21). Ten children had abnormal findings on neurological examination preoperatively; however, nine experienced improvement or resolution of deficits as of their latest follow-up evaluation (mean 17 months). Fusion was achieved with the first operation in 21 of 25 patients; eventually it was attained in all but one. Four patients exhibited persistent spinal instability after an initial procedure. This was caused by erosion of a multistranded cable through the intact arch of C-2 in two cases, by pin site infection necessitating early halo removal in one case, and by slippage in a halo following a Gallie procedure, which was revised with a Brooks fusion in one case. This series, the largest yet published, shows that with appropriate surgical management, posterior upper cervical fusion in the pediatric population is highly successful. Careful attention to halo pin site care and caution in using multistranded cable in young patients may improve results.

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Subagio, Eko Agus, et Seok Woo Kim. « Cervical spine instability and canal stenosis caused by rheumatoid arthritis ». Neurologico Spinale Medico Chirurgico 3, n^o 3 (3 novembre 2020) : 97–102. http://dx.doi.org/10.36444/nsmc.v3i3.115.

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Rheumatoid arthritis (RA) is an inflammatory autoimmune disease that impacts on weakening ligaments, synovial arthritis and cartilage damage. The effect that can occur is instability and neural compression in the upper and sub-axial cervical. The prevalence of atlantoaxial instability (AAI) is around 40-80% among rheumatoid patients, but it is interesting to examine the clinical symptoms that are not so visible despite radiological instability confirmed on the cervical spine. However, once the clinical symptoms of myelopathy occur, the mortality rate will increase sharply. We report a case of a 66-years old female who was admitted to our hospital with gait disturbance and weakness of her lower extremities. Radiographic evaluation of the cervical spine showed erosive destruction of the odontoid process of C2, anterior atlantoaxial subluxation, and thickened yellow ligaments from C3 to C7. Surgery was performed by removal of the posterior arch of C1 and laminectomy C3 to C7, posterior occipito-cervical screw fixation from C3 to C7, combined with atlantoaxial transpedicular screw fixation. A sterno sub-occipitomandibular immobilization (SOMI) orthosis was applied for postoperative immobilization for 12 weeks. Improvement of motoric status noted after surgery.

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Ilahude, Delyuzar, et Udaya Kamiludin. « ABRASION WAVE OBSTRUCTS TOURISM DEVELOPMENT IN COASTAL REGIONS OF BINUANGEUN, LEBAK - BANTEN ». BULLETIN OF THE MARINE GEOLOGY 26, n^o 1 (15 février 2016) : 51. http://dx.doi.org/10.32693/bomg.26.1.2011.34.

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Geographically, the study area is located in the southern coast of Java and also exposed to the influence of wave energy from the southeast, south and southwest. The energy flux of waves generated by surface wind components that affect the coastline and the surrounding waters of Binuangeun. The impact of the wave coming from southeast direction caused a continuous abrasion process in Binuangeun coast and its adjacent areas, included the tourism area in the eastern part of Binuangeun coast towards the center of the study area. The current movement along the coast was accompanied by sediments deposition which tends to westward. The value of sediments supply (Vq) in sample area point number 9 was bigger than the sample area number 4 about 33.703 m3/year within the same direction tendency of sediments deposition. Western part of Binuangeun coastal area would presumably become the sediment accumulation point throughout the year, while the erosion process in the central part of the study area were expanding and occured seasonally. Keywords : abrasion, Binuangeun, flux energy Secara geografis daerah penelitian terletak di pesisir selatan Pulau Jawa dan termasuk pantai terbuka terhadap pengaruh energi gelombang dari arah tenggara, selatan dan barat daya. Energi fluks gelombang yang dibangkitkan oleh komponen angin permukaan berpengaruh terhadap garis pantai perairan Binuangen dan sekitarnya. Efek gelombang dari arah tenggara mengakibatkan proses abrasi di pantai Binuangen dan sekitarnya, terutama kawasan wisata bagian timur pantai Binuangen hingga ke bagian tengah. Pergerakan arus sepanjang pantainya disertai oleh pengendapan sedimen yang cenderung mengarah ke barat. Nilai pasokan sedimen (Vq) pada titik tinjau 9 lebih besar dari pada di titik 4 yaitu sebesar 33.703 m3/tahun dengan pasokan sedimen cenderung bergerak ke arah barat. Daerah pesisir kawasan bagian barat Binuangen diperkirakan akan menjadi zona akumulasi sedimen sepanjang tahun, sementara proses erosi di bagian tengah daerah penelitian tetap berkembang dan berlangsung secara musiman. Kata kunci : abrasi, Binuangen, energi fluks

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