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Imaging the Messier objects remotely from your laptop

CERN Document Server

Adam, Len

2018-01-01

This is a guide for anyone interested in practical astronomy but intimidated by the idea of investing in a telescope. It explores the world of remote observing, which requires nothing more than a laptop and an Internet connection. The book aims to make readers comfortable navigating the plethora of online equipment at their disposal and to show that a challenge like imaging the Messier objects can be fun, simple, and achievable for all. In this text, all 110 Messier objects are discussed, each one remotely imaged with clear instructions on what telescope and camera combinations give the best results. Common astronomical phrases and units are all explained and illustrated to help newcomers get a grasp of terminology. Tidbits of history and quotes from Messier and other astronomers round out this beginner-friendly read, which also features a handy Quick Reference Image Library.
Messier, Copernicus, Flamsteed: The SAF Rare-Book Collection in Paris

Science.gov (United States)

Pasachoff, Jay M.

2014-01-01

The historic books belonging to the Société Astronomique de France, founded by Camille Flammarion in 1887, are located partly in Paris and partly at the Flammarion site in Juvisy, a Paris suburb. Their holdings include first editions of Copernicus's De Revolutionibus and of Flamsteed's star atlas, as well as Messier's own copy of his 1783 and 1784 papers with his handwritten comments and additions. I will describe the fruitless search for a Bevis atlas and the circumstances that led me to inspect these treasures. I thank David Valls-Gabaud and Philippe Morel of the Société Astronomique de France for their hospitality in Paris, Jean-Claude Pecker, and Owen Gingerich for his prior work on Messier's catalogue.
Patagonia

DEFF Research Database (Denmark)

O'Rourke, Dara; Strand, Robert

2017-01-01

.” Specifically, this case study focuses on Patagonia’s durable water repellent (DWR) problem. DWR is a highly effective chemical treatment used to waterproof jackets (supporting the quality objective) but has by-products that are toxic and persist in the environment (undermining the sustainability objective......This article examines the tensions that arise when Patagonia simultaneously pursues sustainability and quality objectives embedded within its mission statement: “Build the best product, cause no unnecessary harm, use business to inspire and implement solutions to the environmental crisis......). This case explores the challenges Patagonia has faced and presents some creative solutions to them....
The cephalic lateral line system of temperate perches (Perciformes: Percichthyidae from Argentinean Patagonia

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Rocío M. Vega

Full Text Available ABSTRACT The species of Percichthys (Percichthyidae are endemic to southern South America. Some authors have pointed out that the genus includes four valid species, based on the morphology of the head, jaws, and fins. A phylogenetic analysis published by other authors suggests that three of them are morphotypes belonging to the same species, Percichthys trucha (Valenciennes, 1833. The aim of this study is to describe for the first time the morphology of the cephalic seismosensory system of Patagonian perches, and how these characters vary in the three morphotypes, in order to provide morphological elements to analyze the taxonomy of these fish species. Comparisons of the cephalic seismosensory system between juveniles and adults were also conducted. Juvenile and adult specimens were collected in the northwestern Argentinean Patagonia. Specimens were bleached in 5% H2O2 and the canal systems of their cephalic lateral line were filled with hematoxylin. Specimens were deposited in the Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Argentina. The cephalic lateral line of the studied specimens is a widened type of canal systems, is not connected to the trunk lateral line, and consists of preopercular-mandibular canal, infraorbital canal, supraorbital canal, temporal canal, supratemporal canal, and a supraorbital commisure. The number of pores increases during the ontogeny, while their diameters decrease. The number, position and size of infraorbital canal pores showed significant differences among morphotypes and juveniles. The interpopulation variation regarding the number, position, and size of pores seems to signal an ongoing process of speciation, which is the result adaptations to different environmental conditions. Our study contributes to the knowledge of the morphology of percichthids and describes for the first time the seismosensory system of temperate perches.
From Messier to Abell: 200 years of science with galaxy clusters

OpenAIRE

Biviano, Andrea

2000-01-01

I review the history of scientific research on galaxy clusters, from 1784, the year of publication of Messier's catalogue, to 1983, the year of George O. Abell's premature death. My review covers four main topics: 1) the distribution of clusters, 2) the cluster components, 3) the cluster structure, 4) the evolution of clusters. I consider both theoretical and observational aspects, but not technical aspects, such as the development of new telescopes and instruments. In total, 529 papers are c...
Marine reptiles from the Late Cretaceous of northern Patagonia

Science.gov (United States)

Gasparini, Z.; Casadio, S.; Fernández, M.; Salgado, L.

2001-04-01

During the Campanian-Maastrichtian, Patagonia was flooded by the Atlantic and reduced to an archipelago. Several localities of northern Patagonia have yielded marine reptiles. Analysis of several assemblages suggests that the diversity and abundance of pelagic marine reptiles in northern Patagonia was higher by the end of the Cretaceous than previously thought. Several plesiosaurids, including Aristonectes parvidens and the polycotylid Sulcusuchus, and the first remains of mosasaurinae have been found. The Cretaceous marine reptile record from South America is scanty. Nevertheless, materials described here suggest that Tethyan and Weddelian forms converged in northern Patagonia, as seen with invertebrates.
Patagonia: tocando las fibras internas

OpenAIRE

Velasco Tafur, Ximena; Borrero Caldas, Silvio

2013-01-01

El presente caso, está enfocado en Patagonia, una compañía que desde sus inicios ha desarrollado una forma poco convencional en su estilo de hacer negocios. La gerencia de Patagonia considera que muchos errores administrativos obedecen a que las empresas formulan las mismas soluciones para todos los problemas que enfrentan. Además, desde la revolución industrial, tales soluciones han privilegiado las ganancias económicas sobre la sostenibilidad ambiental, y el planeta está pasando factura por...
The Maritime Cultural Landscape of Northern Patagonia

Science.gov (United States)

Lira, Nicolás

2017-12-01

This article is a contribution to the study of the indigenous navigation and its boats in the region of northern Patagonia. This article also aims to contribute to the understanding of indigenous navigation practices and technologies and their origins from prehistoric times to the mid-twentieth century. It presents and discusses the concept of Westerdahl's Maritime Cultural Landscape in relation to other landscape concepts. This model is applied to northern Patagonia in order to discuss if it is possible to speak of a true maritime culture in the region. For this purpose, archaeological, historical and ethnographic data are presented in an integrative and innovative methodology for the discipline. Finally, the Maritime Cultural Landscape model will allow the integration of aquatic and terrestrial landscapes as routes traveled by native inhabitants of northern Patagonia and southern Chile, and propose an important and diversified maritime, river and lake tradition.
Plan de comercialización Heliraid Patagonia

OpenAIRE

Mella, Natalia

2012-01-01

La Patagonia Argentina Austral, es considerada un icono a nivel mundial, reúne un conjunto de provincias y aspectos naturales únicos en el mundo1. La Cordillera de los Antes, sus paisajes, su geografía, y su historia. Muchos han sido los aventureros que dieron su vida por explorar y conocer esta zona. Y no todos vivieron para contarlo. Tradicionalmente, la Patagonia se caracterizaba por un escaso desarrollo comercial a raíz de los altos costos y su inaccesibilidad geográfica. Hoy, el desarrol...
Doble difusión a partir de mediciones de microestructura en los canales Martínez y Baker, Patagonia chilena central (47,85°S

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Iván Pérez-Santos

2013-03-01

Full Text Available Con un microperfilador SCAMP (Self Contained Autonomous MicroProfile se detectó un proceso de Doble Difusión Convectiva (DDC, en los canales Martínez y Baker de la Patagonia central, Chile. Este perfilador midió temperatura y salinidad en la columna de agua con una resolución del orden de milímetros. El muestreo se efectuó en diciembre 2011, en 19 estaciones oceanográficas de ~55 m de profundidad. Los registros del microperfilador permitieron detectar la formación de escaleras termohalinas que caracterizan la formación de la DDC. Por medio del ángulo de Turner se confirmó que debajo de una capa superficial fuertemente estratificada (7-10 m se registraron eventos de DDC a profundidades entre 15 y 45 m. La DDC fue débil en la mayoría de los registros pero se evidenciaron eventos fuertes entre 15 y 40 m. En la capa subsuperficial, su origen se debió al intercalamiento de las masas aguas estuarinas (aguas frías y menos saladas encima de las oceánicas (aguas más cálidas y saladas, mientras que en la superficie la interacción océano-atmósfera favoreció su ocurrencia. La DDC en conjunto con el viento, las mareas y las ondas internas, puede constituir un mecanismo importante para la mezcla vertical, influenciando los flujos de calor, el hábitat de las especies marinas en estas profundidades y la exportación de carbono hacia los sedimentos.
TIME-RESOLVED SPECTROSCOPY OF THE POLAR EU CANCRI IN THE OPEN CLUSTER MESSIER 67

International Nuclear Information System (INIS)

Williams, Kurtis A.; Howell, Steve B.; Liebert, James; Smith, Paul S.; Bellini, Andrea; Rubin, Kate H. R.; Bolte, Michael

2013-01-01

We present time-resolved spectroscopic and polarimetric observations of the AM Her system EU Cnc. EU Cnc is located near the core of the old open cluster Messier 67; new proper motion measurements indicate that EU Cnc is indeed a member of the star cluster, and this system therefore is useful to constrain the formation and evolution of magnetic cataclysmic variables. The spectra exhibit two-component emission features with independent radial velocity variations as well as time-variable cyclotron emission indicating a magnetic field strength of 41 MG. The period of the radial velocity and cyclotron hump variations are consistent with the previously known photometric period, and the spectroscopic flux variations are consistent in amplitude with previous photometric amplitude measurements. The secondary star is also detected in the spectrum. We also present polarimetric imaging measurements of EU Cnc that show a clear detection of polarization, and the degree of polarization drops below our detection threshold at phases when the cyclotron emission features are fading or not evident. The combined data are all consistent with the interpretation that EU Cnc is a low-state polar in the cluster Messier 67. The mass function of the system gives an estimate of the accretor mass of M WD ≥ 0.68 M ☉ with M WD ≈ 0.83 M ☉ for an average inclination. We are thus able to place a lower limit on the progenitor mass of the accreting white dwarf of ≥1.43 M ☉ .
Patagonia: nature and territories

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Alejandro Fabián Schweitzer

2014-12-01

This paper analyzes the place occupied by Patagonia in today’s fin de siècle scenario of commodities, hegemony crisis and multi-polar world emergence concurring with the convergence of consumerist guidelines, all of which would apparently lead to an in-depth socio-ecological crisis as well as to an accelerated dispute over nature and territory sense.
Uplift of quaternary shorelines in eastern Patagonia: Darwin revisited

Science.gov (United States)

Pedoja, Kevin; Regard, Vincent; Husson, Laurent; Martinod, Joseph; Guillaume, Benjamin; Fucks, Enrique; Iglesias, Maximiliano; Weill, Pierre

2011-04-01

During his journey on the Beagle, Darwin observed the uniformity in the elevation of coastal Eastern Patagonia along more than 2000 km. More than one century later, the sequences of Quaternary shorelines of eastern Patagonia have been described and their deposits dated but not yet interpreted in terms of geodynamics. Consequently, we i) mapped the repartition of the Quaternary coastal sequences in Argentinean Patagonia, ii) secured accurate altitudes of shoreline angles associated with erosional morphologies (i.e. marine terraces and notches), iii) took into account previous chrono-stratigraphical interpretations in order to calculate mean uplift rates since ~ 440 ka (MIS 11) and proposed age ranges for the higher and older features (up to ~ 180 m), and iv) focused on the Last Interglacial Maximum terrace (MIS 5e) as the best constrained marine terrace (in terms of age and altitude) in order to use it as a tectonic benchmark to quantify uplift rates along the entire passive margin of Eastern South America. Our results show that the eastern Patagonia uplift is constant through time and twice the uplift of the rest of the South American margin. We suggest that the enhanced uplift along the eastern Patagonian coast that interested Darwin during his journey around South America on the Beagle could originate from the subduction of the Chile ridge and the associated dynamic uplift.
Oceanography of the Chilean Patagonia

Science.gov (United States)

Pantoja, Silvio; Luis Iriarte, José; Daneri, Giovanni

2011-03-01

Chilean Patagonia is one of the most extended fjord regions in the world that covers nearly 240,000 km 2 with an extremely complex coastline and topography in one of the least densely populated areas of the country (1-8 inhabitants every 10 km 2). In recent years, the area has been undergoing somewhat intense pressure since several commercial projects in hydroelectricity, tourism, and commercial salmon and mytilid cultures have been developed, or are in progress. Concomitantly, several large research programs have been devised to study the physical, chemical, and biological environment of Patagonia, such as the CIMAR FIORDO, and recently COPAS Sur-Austral based at Universidad de Concepcion, that attempts to close the bridge between oceanographic knowledge and its use by society. In this introductory article we summarize the collection of papers comprising this Special Issue of Continental Shelf Research. These papers deal with aspects of regional oceanography and geology, inorganic and organic geochemistry, ecology of pelagic and benthic organisms, and past changes in productivity.
THE SPECTRAL TYPES OF WHITE DWARFS IN MESSIER 4

International Nuclear Information System (INIS)

Davis, D. Saul; Richer, Harvey B.; Rich, R. Michael; Reitzel, David R.; Kalirai, Jason S.

2009-01-01

We present the spectra of 24 white dwarfs in the direction of the globular cluster Messier 4 obtained with the Keck/LRIS and Gemini/GMOS spectrographs. Determining the spectral types of the stars in this sample, we find 24 type DA and 0 type DB (i.e., atmospheres dominated by hydrogen and helium, respectively). Assuming the ratio of DA/DB observed in the field with effective temperature between 15,000-25,000 K, i.e., 4.2:1, holds for the cluster environment, the chance of finding no DBs in our sample simply due to statistical fluctuations is only 6 x 10 -3 . The spectral types of the ∼100 white dwarfs previously identified in open clusters indicate that DB formation is strongly suppressed in that environment. Furthermore, all the ∼10 white dwarfs previously identified in other globular clusters are exclusively type DA. In the context of these two facts, this finding suggests that DB formation is suppressed in the cluster environment in general. Though no satisfactory explanation for this phenomenon exists, we discuss several possibilities.
Patagonia, Land of Nomads: A Glance at a Territory Shaped by Displacement

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Pablo Chiuminatto

2016-05-01

Full Text Available By the end of the nineteenth century, as global voyages became popular, and transcontinental empires settled, remote corners of the third world such as Patagonia began to be explored and became the subject of European travel literatures. The opening of this region to the global scenario produced profound transformations in its territorial conformation, poetic imaginary, and local culture. As Patagonia became a land of travellers, local nomads which had inhabited this land for centuries became extinguished. The historical context of this re-shaping is conceptualised in literary theory through notions such as nomadism, elaborated by Gilles Deleuze and its aesthetical counterpart, geo-poetics, by Kenneth White. The travel literature about Patagonia, such as that produced by Charles Darwin, Lady Florence Dixie, and Bruce Chatwin, depicts the difficulties these travellers faced in trying to endow their writings of adequate descriptions and images. Instead, they recurred to images from their homeland, and thus created an imaginary of Patagonia through displacement: their own, and that of images brought by themselves to this land. When Chilean poets like Gabriela Mistral and Pablo Neruda begun to write about Patagonia, they found it already populated by strange images, shaped indeed, by nomads, travellers and dis-located identities.
Estado actual del conocimiento de la familia Ceratopogonidae en la Patagonia (Diptera: Nematocera Current knowledge of the family Ceratopogonidae in Patagonia (Diptera: Nematocera

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Gustavo R. Spinelli

2009-06-01

Full Text Available Ceratopogonidae incluye pequeños dípteros nematoceros que crían en hábitats acuáticos o semiacuáticos. Hasta los '80, el conocimiento de su taxonomía en la Patagonia se hallaba limitado a la contribución de los comienzos de los '30 de Ingram y Macfie, sobre la base de material capturado en 1926-27, en el área del Parque Nacional Nahuel Huapi y zonas vecinas de Chile. En los últimos 25 años, se pusieron en marcha diferentes proyectos, resultando la descripción o registro de numerosos taxones para la región. Si se contabilizan los datos publicados, 102 especies habitan en la Patagonia, de las cuales 86 (84,31% son endémicas para la región. Este alto porcentaje es evidente en los bosques de Nothofagus, con 71 especies endémicas de este bioma, nueve lo son de la estepa y seis presentan registros en bosque y estepa. Datos aún no publicados concuerdan con este esquema. Diecinueve géneros están representados en la Patagonia, diez de ellos con amplia distribución, tres de distribución transantártica y seis son endémicos para el área. Para la misma, se hallan publicadas las revisiones de Forcipomyia, Atrichopogon, Borkenthelea, Macrurohelea y Paradasyhelea; se han finalizado y aún no publicado aquellas de Dasyhelea y Palpomyia, está muy avanzada la de Stilobezzia y se prevé comenzar con las de Austrohelea, Austrosphaeromias, Physohelea y Bezzia. Se calcula que estos datos no divulgados contienen al menos 55 especies todavía no descriptas. Con respecto a los aspectos biogeográficos se pueden destacar estudios que tienden a establecer relaciones entre las áreas reconocidas en esquemas biogeográficos propuestos para la región andina.Ceratopogonidae includes small nematoceran Diptera which breed in aquatic and semiaquatic habitats. Until the 80´s its taxonomic knowledge in Patagonia was limited to the early 30´s contribution of Ingram and Macfie, from material collected in 1926-27 in the area of the Nahuel Huapi National
The impact of Chilean migration on employment in Patagonia.

Science.gov (United States)

Cariola Sanz, L

1989-06-01

This paper discusses the employment situation of Chilean migrant workers, their impact on labor markets in Patagonia, Argentina, and the government's past and projected responses to this phenomenon. In 1980, Chilean inhabitants of patagonia comprised 11% of the area's population. Chilean migration to patagonia was closely linked to economic activities that began to flourish in the 20th century, such as livestock raising, fruit and vegetable cultivation, and mining for coal and petroleum. No Chilean migrants work in a wide range of sectors. In Patagonia's southern provinces availability and ability to withstand rigorous climate conditions are the main factors which account for the prevalence of Chilean manpower. Chilean migrants do not in general displace local manpower. Legislation and the permeability of the border ensure that most workers enter the country as tourists. Clandestine migration is not an issue. Illegal migrants have provoked negative reactions for several reasons: 1) they comprise a marginal population without formal citizenship; 2) being employed as clandestine workers, they pay no social security, nor do their employers; 3) being illegal, they are obliged to accept lower wages and inferior working conditions which creates unfair competition within labor markets; and 4) as a result of these conditions, xenophobic and endophobic attitudes in relations with Argentine nationalists are reinforced. The government has attempted to solve these problems through various measures. Beginning in 1934, most foreigners entered Argentina with a tourist visa, becoming illegal when they stayed beyond authorized limits. Several measures over the years provided amnesty to illegal migrants. Currently, the law promotes immigration, monitors the admission of foreigners to the country and stipulates their rights and obligations. The law lists 115 articles on immigration promotion and on regulation of the movements of foreigners. Because of the present economic crisis in
Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera de la Patagonia Current state of the taxonomic knowledge of the Chironomidae fauna (Diptera: Nematocera from Patagonia

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Mariano Donato

2009-06-01

Full Text Available La familia Chironomidae (Diptera: Nematocera es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK y del material de colección del Museo de La Plata (Argentina. En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58 y machos y hembras (n=43, ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo.The Chironomidae (Diptera: Nematocera family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. Representatives of this family can exploit a wide range of environmental gradients. The information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the Natural History Museum (UK and the collection material from Museo de La Plata (Argentina. Nine subfamilies are recorded from Patagonia, being the monotypic subfamily Chilenomyiinae endemic for the area. From the 111 known
Freshwater fishes of Patagonia: conservation and fisheries.

Science.gov (United States)

Cussac, V E; Habit, E; Ciancio, J; Battini, M A; Riva Rossi, C; Barriga, J P; Baigún, C; Crichigno, S

2016-07-01

The absence of much literature on the Patagonian fish fauna in comparison with that of the neotropics, has previously been blamed on its poor species diversity. Knowledge of the fishes of Patagonia, however, rose sharply at the beginning of the present century, allowing for an understanding of the complex biogeographical history that has led to the present diversity and distribution patterns. There are several new and potential threats to biodiversity and conservation of Patagonian fishes, such as the introduction of exotic species, damming, climate change and changes geared to safeguard economic interests, often acting synergistically. A great amount of new information is now available and the aim of the present review is to articulate this knowledge in a comprehensive way in order to aid in the development of tools to face the increasing challenges posed by environmental change and human activity. Knowledge about fishes of Patagonia has grown at the same time as human actions, and presence. © 2016 The Fisheries Society of the British Isles.

Biometric identification of capillariid eggs from archaeological sites in Patagonia.

Science.gov (United States)

Taglioretti, V; Fugassa, M H; Beltrame, M O; Sardella, N H

2014-06-01

Numerous eggs of capillariid nematodes have been found in coprolites from a wide range of hosts and in raptor pellets in archaeological samples from Patagonia. The structure and sculpture of the eggshell of these nematodes and their biometry are commonly used for identification. The aim of this study was to determine whether eggs of the genus Calodium with similar morphology, found in different archaeological samples from Patagonia, belong to the same species. For this purpose, capillariid eggs (N= 843) with thick walls and radial striations were studied by permutational multivariate analysis of variance (PERMANOVA). Eggs exhibiting similar shape and structure also showed similar biometry, regardless of the zoological origin of coprolites (P= 0.84), host diet (P= 0.19), character of the archaeological sites (P= 0.67) and chronology (P= 0.66). Thus, they were attributed to the same species. We suggest that an unidentified zoonotic species of the genus Calodium occurred in the digestive tract of a wide range of hosts in Patagonia during the Holocene and that both human and animal populations were exposed to this parasite during the Holocene in the study area.
A new burmagomphid dragonfly from the Eocene of Patagonia, Argentina

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Julián F. Petrulevičius

2017-11-01

Full Text Available A new burmagomphid anisopteran, Satelitala soberana gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is characterised by hindwing characters such as the subdiscoidal triangle not elongated; anal loop divided longitudinally; paranal cell divided longitudinally; five terminal cells between RP and MA; five terminal cells between MP and CuA; and obtuse angle between PsA and CuP+AA. Burmagomphid dragonflies were represented so far only by one specimen from the middle Cretaceous of Southeast Asia. This new record extends the distribution to Patagonia, to the Cenozoic, and also to paleolake deposits.
Telón de fondo: Paisajes de desierto y alteridad en la fotografía de la Patagonia (1880-1900 Backdrop: Desert and Alterity Landscapes in the Photography of Patagonia (1880-1900

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Carlos Masotta

2009-12-01

Full Text Available El paisaje patagónico construido por la fotografía del período 1880-1900 fue un marco en donde se llevó a cabo el ingreso civilizatorio. Luego de una caracterización general del problema (el paisaje desierto como «escenificación de ausencia» en torno a los primeros álbumes de Estado sobre la región, centro el análisis de este artículo en dos obras que describieron el Territorio de Chubut: Viaje a la Patagonia Austral (1886 del Coronel Luis Fontana y la Excursión a la Patagonia y a los Andes de Aarón Anchorena (1902. Entre ellas puede observarse la articulación de una mirada militar y civil donde el paisaje fotográfico del desierto se involucra en la toma material y simbólica del territorio como un escenario donde se «naturaliza» la actuación de un ingreso civilizatorio y la desaparición de los pueblos indígenas.The Patagonian landscape built up by photography during the 1880-1900 periods was the framework in which the civilizing entrance took action. After a general description of the problem (the deserted landscape as the staging of absence about the first State's albums on the region, I focus the analysis on two works describing the Territory of Chubut: Viaje a la Patagonia Austral (Trip to Southern Patagonia by Coronel Luis Fontana (1886 and Excursion a la Patagonia y a los Andes (Tour to Patagonia and the Andes, de Aaron Anchorena (1902. The articulation of a military and civil glance can be observed between them, where the photographic landscape of the desert is involved in the material and symbolic shot of the territory as a stage where the acting of a civilizing entrance and the disappearance of the indigenous peoples is naturalized.
A new pentatomoid bug from the Ypresian of Patagonia, Argentina

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Julián F. Petrulevičius

2016-12-01

Full Text Available A new pentatomoid heteropteran, Chinchekoala qunita gen. et sp. nov. is described from the lower Eocene of Laguna del Hunco, Patagonia, Argentina. The new genus is mainly characterised by cephalic characters such as the mandibular plates surpassing the clypeus and touching each other in dorsal view; head wider than long; and remarkable characters related to the eyes, which are surrounded antero-laterally and posteriorly by the anteocular processes and the pronotum, as well as they extend medially more than usual in the Pentatomoidea. This is the first pentatomoid from the Ypresian of Patagonia and the second from the Eocene in the region, being the unique two fossil pentatomoids in Argentina.
Green marketing impact on a company’s success : studying the case of Patagonia

OpenAIRE

Ventura, Manuel Robles Machado Simões

2016-01-01

The increased demand for products with low environmental impact has increased the number of green marketing campaigns released during the last years. However, the impact of green marketing in companies’ performance is not clear. It mainly depends on the company’s characteristics and the perceived honesty of their green claims. Thus, the present study aimed to analyze the impact of green marketing in a particular company, Patagonia. Patagonia is recognized as a pioneer in corporate environment...
Airborne laser altimetry survey of Glaciar Tyndall, Patagonia

DEFF Research Database (Denmark)

Keller, K.; Casassa, G.; Rivera, A.

2007-01-01

The first airborne laser altimetry measurements of a glacier in South America are presented. Data were collected in November of 2001 over Glaciar Tyndall, Torres del Paine National Park, Chilean Patagonia, onboard a Twin Otter airplane of the Chilean Air Force. A laser scanner with a rotating...
Distribución del ictioplancton en la Patagonia austral de Chile: potenciales efectos del deshielo de Campos de Hielo Sur Ichthyoplankton distribution in South Patagonia, Chile: potential effects of ice melting from the Southern Ice Field

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Mauricio F Landaeta

2011-07-01

Full Text Available Durante octubre-noviembre de 2009 se realizó un crucero oceanográfico entre 50 y 53°S de Chile austral, en las cercanías del glaciar Campos de Hielo Sur. Las estaciones cercanas al glaciar presentaron baja temperatura (1-3°C y salinidad ( 0,1 ciclos s-1. Los principales taxa del ictioplancton fueron huevos y larvas de sardina fueguina Sprattus fuegensis, pez hacha Maurolicus parvipinnis, Macrouridae y merluza austral Merluccius australis. El desove principal de S. fuegensis (~ 8000 huevos 10 m-2 ocurrió en zonas mezcladas de la plataforma continental adyacente, mientras que el desove de M. parvipinnis ocurrió en canales intermedios asociado a valores intermedios de estabilidad (N~0,06 ciclos s-1. Se observó una nula o baja abundancia de huevos y larvas de peces en las cercanías del glaciar, y la abundancia de huevos de M. parvipinnis estuvo relacionada positivamente con la temperatura y salinidad de la columna de agua y negativamente con la estabilidad de la columna de agua. Además, hubo una relación negativa entre la densidad del agua de mar y el diámetro de los huevos de S. fuegensis. La relación entre deshielo e ictioplancton podría tener consecuencias en el transporte advectivo y mortalidad masiva de huevos y larvas de peces y el acople pelágico-bentónico en la Patagonia austral de Chile. Como el cambio climático global ha incrementado los deshielos de glaciares en latitudes altas, y el aumento del ingreso de aguas de baja temperatura y salinidad podría tener consecuencias en el ictioplancton de la Patagonia chilena.In October-November 2009, an oceanographic survey was carried out between 50 and 53°S off southern Chile, near the Southern Ice Field. The stations near the glacier showed low temperatures (1-3°C and salinity ( 0.1 cycles s-1. Main ichthyoplankton taxa were eggs and larvae of southern sprat Sprattus fuegensis, lightfish Maurolicus parvipinnis, Macrouridae, and southern hake Merluccius australis. The main
Quantifying mass balance processes on the Southern Patagonia Icefield

DEFF Research Database (Denmark)

Schaefer, M.; Machguth, Horst; Falvey, M.

2015-01-01

We present surface mass balance simulations of the Southern Patagonia Icefield (SPI) driven by downscaled reanalysis data. The simulations were evaluated and interpreted using geodetic mass balances, measured point balances and a complete velocity field of the icefield for spring 2004. The high m...
A tale of three hydros - post-privatisation in Patagonia

International Nuclear Information System (INIS)

Smith, H.F.

1994-01-01

When Argentina's state-owned utility, operating in northern Patagonia, sold off hydro-electric generating plants in 1993, they were bought by several North American utility companies. This article looks at the problems these companies encountered and examines whether the enterprise has shown itself to be economically valuable. (UK)
UVR-induced photoinhibition of summer marine phytoplankton communities from Patagonia

NARCIS (Netherlands)

Villafane, Virginia E.; Janknegt, Paul J.; de Graaff, Marco; Visser, Ronald J. W.; de Poll, Willem H. van; Buma, Anita G. J.; Helbling, E. Walter

During austral summer 2006, experiments were carried out to evaluate the effects of ultraviolet radiation (UVR, 280-400 nm) on carbon fixation of natural phytoplankton assemblages from Patagonia (Argentina). Surface water samples were collected (ca. 100 m offshore) at mid morning using an
Variaciones glaciales durante el Holoceno en Patagonia Central, Aisén, Chile: evidencias geomorfológicas Holocene glacial variations in Central Patagonia, Aisén, Chile: geomorphological evidences

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María Mardones

2011-07-01

Full Text Available Durante el Holoceno, avances y retrocesos glaciares geomorfológicamente registrados caracterizan la Patagonia. Este artículo presenta la evolución geomorfológica y las evidencias de fluctuaciones glaciales holocénicas de una región patagónica, que servirán de referencia para el estudio de la evolución paleoclimática Postglacial del extremo sur de Sudamérica. El área de trabajo es la cuenca del río Blanco (45°30'S, en la Patagonia Central (Región de Aisén, Chile. Dataciones radiométricas de sedimentos orgánicos de morrenas terminales aportan antecedentes preliminares de dos avances glaciares: el primero, representado por la morrena frontal del lago Elizalde, arroja una edad inferior a 9.370±50 años 14C AP (10.700 a 10.480 cal. años AP, lo que cronológicamente ubica este evento glaciar en el Holoceno Temprano. Esta progresión del hielo es 100 a 200 años más antigua que aquella observada inmediatamente al sur del área de estudio, en el margen oriental del lago General Carrera (o lago Buenos Aires en Argentina y aproximadamente 100 años más joven, que la registrada en la morrena de Puerto Banderas I (lago Argentino, 50°S. Este resultado sugiere un patrón de comportamiento de los glaciares de Patagonia Central diferente a aquel observado por otros investigadores en la Región de Los Lagos (41°S y en la Región de Magallanes (54°S, donde no se registran huellas de reavances glaciares durante el Holoceno Temprano. Luego de un importante retroceso hacia el oeste, un reavance glaciar más reciente se habría producido en el valle del río Quetro (afluente del río Blanco, a una edad inferior a 2.250±40 AP (2.340 a 2.150 cal. años AP, comparable con el estadio frío del Neoglacial Medio, verificado en distintos puntos de la Patagonia. Confrontando estos resultados con registros palinológicos previamente publicados por otros autores, interpretamos que las causas de ambas fluctuaciones glaciales son variaciones regionales
New records of water mites (Acari: Hydrachnidia, Halacaroidea) from Patagonia (Chile)

NARCIS (Netherlands)

Pešić, V.; Smit, H.; Datry, T.

2010-01-01

New records of water mite species (Acari: Hydrachnidia, Halacaroidea) from Patagonia (Southern Chile) are reported. Four species, Anisitsiellides australis Smit, 2002, Peregrinacarus falklandensis Bartsch, 2001, Lobohalacarus weberi (Romijn & Viets, 1924) and Soldanellonyx monardi Walter, 1919 are
Difilobotriasis humana en la Patagonia, Argentina Human diphyllobothriasis in Patagonia, Argentina

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Liliana Semenas

1997-06-01

Full Text Available OBJETIVO: El objetivo del trabajo fué detectar hospedadores humanos en la zona andino patagónica argentina, teniendo en cuenta las prácticas de pesca desportiva y la importancia de los salmónidos dentro de la zona. MATERIAL Y METODO: Entre 1986 y 1995 se implementaron Campañas de Información en los laboratorios de Análisis Clínicos de la región andinopatagónica argentina, destinadas a lograr una detección más eficiente de la difilobotriasis, a través de análisis coproparasitológicos. RESULTADOS: Adicionalmente, se confeccionaron planillas destinadas a recoger información sobre las características de la infección, del tratamiento y del paciente. Durante este período se detectaron 13 nuevos casos humanos, por identificación directa del parásito o por la presencia de huevos en materia fecal. Las características de las infecciones responden a las descriptas para el género Diphyllobothrium. CONCLUSIONES: En la región, los salmónidos son los peces predilectos en la pesca deportiva. Estos peces, frecuentemente parasitados con larvas, constituyen la principal fuente de contagio para el hombre al ser consumidos insuficientemente cocidos o ahumados en frío.OBJECTIVE: In view of the amateur fishing practices and the importance of salmonids in the region the study sets out to detect human hosts in the Andean-Patagonian zone. MATERIAL AND METHOD: Information campaigns were carried out by Clinical Analysis Laboratories of Andean Patagonia between 1986 and 1995 to detect diphyllobothriasis more efficiently by means of coproparasitological analysis. RESULTS: Further, forms were prepared for the collection of information about infection, treatment and the characteristics of the human host. During this period 13 new cases were registered either through direct identification of the parasite or through the presence of eggs in the faeces. The characteristics of infection are similar to those described for the genus Diphyllobothrium
Ploidy levels and reproductive behaviour in invasive Hieracium pilosella in Patagonia

Czech Academy of Sciences Publication Activity Database

Krahulec, František; Krahulcová, Anna

2011-01-01

Roč. 11, - (2011), s. 25-31 ISSN 1619-0033 R&D Projects: GA ČR GA206/08/0890 Institutional research plan: CEZ:AV0Z60050516 Keywords : Patagonia * ploidy levels * hybridization Subject RIV: EF - Botanics
"Jejenes" (Diptera: Simuliidae of Nahuel Huapi National Park, Patagonia, Argentina: Preliminary results "Jejenes" (Diptera: Simuliidae del Parque Nacional Nahuel Huapi, Patagonia, Argentina: Resultados preliminares

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Luis M. Hernández

2009-06-01

Full Text Available The Simuliidae is a family of Diptera with approximately 2072 described species worldwide. The females of the majority of the species feed from vertebrates' blood, which makes them a significant plague that affects both men as well as cattle, birds, and other vertebrates. The objective of this paper is to create an inventory of Simuliidae and to reveal certain aspects of the biology and distribution of this family of aquatic insects in the Nahuel Huapi National Park. Moreover, information on the zoogeography of Simuliidae in Patagonia is provided. Five genera, 3 subgenera and 32 species Simuliidae are recorded from Patagonia: Cnesia (three spp., Cnesiamima (one sp., Gigantodax (14 spp., Paraustrosimulium (one sp., Simulium (Ectemnaspis (one sp., S. (Psaroniocompsa (one sp. and S. ( Pternaspatha (11 spp., At present, we have collected all five genera, one subgenus of Simulium (Pternaspatha, and 19 species of Simuliidae in the park, which amounts to 57% of the Simuliidae fauna in this area. Puerto Blest, a characteristic area of the High-Andean phytogeographical province (humid forest, showed the highest diversity of Simuliidae.Los simúlidos pertenecen a una familia de Diptera (Simuliidae con alrededor de 2.072 especies descritas a nivel mundial. Las hembras de la mayoría de las especies se alimentan con sangre de vertebrados, lo cual las convierte en importantes plagas que afectan tanto al hombre como al ganado, aves y otros vertebrados. Los objetivos de este trabajo son llevar a cabo un inventario de Simuliidae y dar a conocer algunos aspectos de la biología y la distribución de esta familia de insectos acuáticos en el Parque Nacional Nahuel Huapi, Argentina. Además, se proporciona información sobre la biogeografía de Simuliidae en la Patagonia. Cinco géneros, un subgénero y 32 especies de simúlidos han sido registrados para Patagonia: Cnesia (3 spp., Cnesiamima (1 sp., Gigantodax (14 spp., Paraustrosimulium (1 sp., Simulium
Stability of guest molecules in urea canal complexes by canal polymerization

International Nuclear Information System (INIS)

Yoshii, Fumio; Makuuchi, Keizo

1995-01-01

It was found that various organic materials are attracted into urea canal by hexanediol diacrylate (HDDA) and long chain compounds. This means that materials which does not form complex by itself are induced in canal by HDDA and long chain compounds. To include with stability perfumes, insecticides, attractants and repellents in urea canal, leaf alcohol was used as a model compound for guest molecules in the canal. The leaf alcohol from the canal released gradually over many days and the release was inhibited for 15 days by long chain compounds and for 30 days by polymerized HDDA after irradiation. After releasing, the leaf alcohol in the canal remained 25 % stable for long chain compounds and 40 % for polymerized HDDA. The dose required for stabilization of leaf alcohol in the urea canal by canal polymerization of HDDA was 30 kGy. (author)
Root canal irrigants

OpenAIRE

Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

2010-01-01

Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...
Late cretaceous aquatic plant world in Patagonia, Argentina.

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N Rubén Cúneo

Full Text Available In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla and a monocot (Araceae. Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae. Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form and the eudicot angiosperm Nelumbo (Nelumbonaceae are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae, ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America.
Late Cretaceous Aquatic Plant World in Patagonia, Argentina

Science.gov (United States)

Cúneo, N. Rubén; Gandolfo, María A.; Zamaloa, María C.; Hermsen, Elizabeth

2014-01-01

In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America. PMID:25148081
OSTEOMETRÍA DE VICUGNA VICUGNA MOLINA, 1782 EN EL PLEISTOCENO FINAL DE PATAGONIA MERIDIONAL CHILENA: IMPLICANCIAS PALEOECOLÓGICAS Y BIOGEOGRÁFICAS / Osteometry of Vicugna vicugna Molina, 1782 in the late Pleistocene of southern chilean Patagonia

Directory of Open Access Journals (Sweden)

Rafael Labarca Encina

2009-12-01

Full Text Available Se presenta un análisis osteométrico uni y multivariado con los materiales fósiles -principalmente huesos cortos y falanges- de Vicugna sp. del yacimiento Cueva Lago Sofía 4 (13500 – 11000 AP, ubicado en la provincia de Última Esperanza (Región de Magallanes, Chile. Los resultados indican que los elementos analizados poseen un tamaño compatible con los registrados para Vicugna vicugna, no superando en ningún caso a los especímenes conocidos para Vicugna gracilis del Pleistoceno de la región Pampeana. Esto confirma la información morfológica y de ADN antiguo que indicaba la presencia de Vicugna vicugna en la Patagonia meridional chilena. Se discuten los resultados en términos taxonómicos, biogeográficos y paleoecológicos sugiriendo que la presencia de este taxón fuera de su rango actual de distribución se debió a las condiciones ambientales compartidas entre la Puna y Patagonia austral durante la transición Pleistoceno-Holoceno. La extinción de V. vicugna se habría debido al impacto de los cambios climáticos ocurridos al inicio del Holoceno producto de su dieta pastadora y etología no migratoria y territorial, a lo que se habría sumado una caza por parte de depredadores humanos y no humanos.Palabras clave: género Vicugna, osteometría, Pleistoceno, Patagonia AbstractThis contribution presents the results of single and multi-variable osteometric analyses performed on a sample of short bones and phalanxes assigned to Vicugna sp. from Lago Sofía Cave 4 site (13500 – 11000 BP, Región de Magallanes, Chile. The elements analyzed show a similar size to the reference collections for Vicugna vicugna, and do not exceed the metrics for the pampean pleistocenic specimens of Vicugna gracilis. This confirms the morphological and ancient DNA data that indicated the presence of vicuña in southern Chilean Patagonia. The taxonomic, biogeographic and palaeoecologic discussion of these results, suggests that the presence of this

Aeolian sediment mass fluxes on a sandy soil in Central Patagonia

NARCIS (Netherlands)

Sterk, G.; Parigiani, J.; Cittadini, E.; Peters, P.; Scholberg, J.; Peri, P.

2012-01-01

The climate of Patagonia is semi-arid and characterised by frequent strong winds. Wind erosion is potentially a serious soil degradation process that impacts long-term sustainability of local agricultural systems, but the conditions and the rates of wind erosion in this region have not been
Latest Pleistocene and Holocene Glacier Fluctuations in southernmost Patagonia

Science.gov (United States)

Menounos, B.; Maurer, M.; Clague, J. J.; osborn, G.; Ponce, F.; Davis, P. T.; Rabassa, J.; Coronato, A.; Marr, R.

2011-12-01

Summer insolation has been proposed to explain long-term glacier fluctuations during the Holocene. If correct, the record of glacier fluctuations at high latitudes in the Southern Hemisphere should differ from that in the Northern Hemisphere. Testing this insolation hypothesis has been hampered by dating uncertainties of many Holocene glacier chronologies from Patagonia. We report on our ongoing research aimed at developing a regional glacier chronology at the southern end of the Andes north and west of Ushuaia, Argentina. We have found evidence for an advance of cirque glaciers at the end of the Pleistocene; one or locally two closely spaced moraines extend up to 2 km beyond Little Ice Age moraines. Radiocarbon dating of terrestrial macrofossils recovered from basal sediments behind two of these moraines yielded ages of 10,320 ± 25 and 10,330 ± 30 14C yr BP. These moraines may record glacier advances coeval with the Antarctic Cold Reversal; surface exposure dating of these moraines is currently in progress to test this hypothesis. We find no evidence of Holocene moraines older than 6800 14C yr BP, based on the distribution of Hudson tephra of that age. At some sites, there is evidence for an early Neoglacial advance of glaciers slightly beyond (Peru. We have documented multiple wood mats with stumps in growth position separated by till units in a 100 m section of the northeast lateral moraine at Stoppani Glacier (54.78 S, 68.98 W), 50 km west of Ushuaia. Ten radiocarbon ages on these wood mats range in age from 3510 ± 15 to 135 ± 15 14C yr BP. The mats decrease in age up-section; many overlap with published age ranges for Neoglacial advances in western Canada. Taken together, these data: a) do not support the summer insolation hypothesis for Holocene glacier fluctuations in southernmost Patagonia; b) confirm paleobotanical evidence for a warm, dry early Holocene; and c) suggest that many Neoglacial advances in southernmost Patagonia and western North America
Fe-Ni Micrometorites from Upper Jurassic Cañadon Asfalto Fm., Patagonia, Argentina

Science.gov (United States)

Matteini, M.; Hauser, N.; Cabaleri, N.; Silva Nieto, D.; Cuadros, F. A.; Reyes, S.

2014-09-01

Microspherules from an upper Jurassic sediments from Patagonia, show mineralogical, geochemical and textural features very similar to those reported for I-type micrometeorites whereas some spherules are interpreted as typical G-type micrometeorites.
Geochronologic evidence of a large magmatic province in northern Patagonia encompassing the Permian-Triassic boundary

Science.gov (United States)

Luppo, Tomás; López de Luchi, Mónica G.; Rapalini, Augusto E.; Martínez Dopico, Carmen I.; Fanning, Christopher M.

2018-03-01

The Los Menucos Complex (northern Patagonia) consists of ∼6 km thick succession of acidic and intermediate volcanic and pyroclastic products, which has been traditionally assigned to the Middle/Late Triassic. New U/Pb (SHRIMP) zircon crystallization ages of 257 ± 2 Ma at the base, 252 ± 2 Ma at an intermediate level and 248 ± 2 Ma near the top of the sequence, indicate that this volcanic event took place in about 10 Ma around the Permian-Triassic boundary. This volcanism can now be considered as the effusive terms of the neighboring and coeval La Esperanza Plutono-Volcanic Complex. This indicates that the climax of activity of a large magmatic province in northern Patagonia was coetaneous with the end-Permian mass extinctions. Likely correlation of La Esperanza- Los Menucos magmatic province with similar volcanic and plutonic rocks across other areas of northern Patagonia suggest a much larger extension than previously envisaged for this event. Its age, large volume and explosive nature suggest that the previously ignored potential role that this volcanism might have played in climatic deterioration around the Permian-Triassic boundary should be investigated.
Genomic insights into the origin and diversification of late maritime hunter-gatherers from the Chilean Patagonia.

Science.gov (United States)

de la Fuente, Constanza; Ávila-Arcos, María C; Galimany, Jacqueline; Carpenter, Meredith L; Homburger, Julian R; Blanco, Alejandro; Contreras, Paloma; Cruz Dávalos, Diana; Reyes, Omar; San Roman, Manuel; Moreno-Estrada, Andrés; Campos, Paula F; Eng, Celeste; Huntsman, Scott; Burchard, Esteban G; Malaspinas, Anna-Sapfo; Bustamante, Carlos D; Willerslev, Eske; Llop, Elena; Verdugo, Ricardo A; Moraga, Mauricio

2018-04-24

Patagonia was the last region of the Americas reached by humans who entered the continent from Siberia ∼15,000-20,000 y ago. Despite recent genomic approaches to reconstruct the continental evolutionary history, regional characterization of ancient and modern genomes remains understudied. Exploring the genomic diversity within Patagonia is not just a valuable strategy to gain a better understanding of the history and diversification of human populations in the southernmost tip of the Americas, but it would also improve the representation of Native American diversity in global databases of human variation. Here, we present genome data from four modern populations from Central Southern Chile and Patagonia ( n = 61) and four ancient maritime individuals from Patagonia (∼1,000 y old). Both the modern and ancient individuals studied in this work have a greater genetic affinity with other modern Native Americans than to any non-American population, showing within South America a clear structure between major geographical regions. Native Patagonian Kawéskar and Yámana showed the highest genetic affinity with the ancient individuals, indicating genetic continuity in the region during the past 1,000 y before present, together with an important agreement between the ethnic affiliation and historical distribution of both groups. Lastly, the ancient maritime individuals were genetically equidistant to a ∼200-y-old terrestrial hunter-gatherer from Tierra del Fuego, which supports a model with an initial separation of a common ancestral group to both maritime populations from a terrestrial population, with a later diversification of the maritime groups.
Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera de la Patagonia

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Mariano DONATO

2009-01-01

Full Text Available La familia Chironomidae (Diptera: Nematocera es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK y del material de colección del Museo de La Plata (Argentina. En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58 y machos y hembras (n=43, ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo.
Canal shaping of different single-file systems in curved root canals

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Maurizio D'Amario

2017-12-01

Full Text Available Background/Purpose: This study compared maintenance of canal anatomy, occurrence of apical transportation, and working time observed after instrumentation with One Shape New Generation rotary system (Micro-Mega, with those observed after instrumentation with Reciproc (VDW and WaveOne (Dentsply-Maillefer reciprocating systems. Materials and methods: The mesial canals of 45 mandibular molars (curvature angles between 35Â° and 45Â° were selected. Specimens were randomly divided into three groups, and canal preparations were performed using One Shape, Reciproc, or WaveOne systems (size #25. A digital double radiographic technique was used to determine apical transportation and change in angle of curvature. Also, working time and instrument failures were recorded. Data were statistically analyzed. Results: During preparation, no file fractured. No statistically significant differences were found among groups. No system showed a significantly faster preparation time than others (P>0.05. All instruments maintained the original canal curvature well and were safe to use. Conclusion: Both continuous rotary instrument and reciprocating systems did not have any influence on the presence of apical transportation or caused an alteration in angle of canal curvature. Keywords: canal curvature, canal straightening, endodontics, reciprocating motion, single file instrumentation
La proyección colonial de Chile a la Patagonia Insular en el siglo XVIII

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Urbina Carrasco, María Ximena

2011-12-01

Full Text Available In this article, the geopolitical consequences of the shipwreck of the English frigate Wager and the landfall of the ship Anna into the coasts of the Western Insular Patagonia in 1741 are presented, which were part of the fleet of George Anson. The news reporting the English presence in the deserted and unknown insular and coastal territory southernmost Chiloé, and which had disseminated towards the end of the continent, promoted the deployment of different actions tending to make presence noted, such as military and missionary expeditions, fort establishment and area patrols. None of the latter implied a permanent settlement or effective incorporation of such border, although they indeed involved the creation of a «mobile frontier» for Chiloé and the development of a Western Patagonia image.

Este artículo presenta las consecuencias geopolíticas del naufragio de la fragata inglesa Wager y la recalada de otro barco, el Anna, que formaban parte de la flota de George Anson, en las costas de la Patagonia Occidental Insular en 1741. La noticia de la presencia inglesa en el despoblado y desconocido territorio insular y bordemarino al sur de Chiloé, y que se proyectaba al fin del continente, generó el despliegue de acciones tendentes a marcar presencia, como expediciones militares y misionales, la fundación de un fuerte y el patrullaje por la zona. Nada de esto se tradujo en un asentamiento permanente o incorporación efectiva de dicha frontera, pero si en la conformación de una «frontera móvil» de Chiloé, y la construcción de una imagen de la Patagonia Occidental.
Modulation of Fire Regimes by Vegetation and Site Type in Southwestern Patagonia Since 13 ka

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Patricio I. Moreno

2018-04-01

Full Text Available The degree to which vegetation and site type have influenced fire regimes through the Holocene has not been investigated in detail in the temperate ecosystems of southern Patagonia. Here we present a first attempt using a paired-basin approach to study the evolution of fire regimes in sectors dominated by humid Nothofagus forests and the xeric Patagonian steppe in the Magallanes region of Chilean Patagonia (51°S. We analyzed sediment cores from two small lakes and a bog located within the same climate zone on opposite sides of the forest-steppe ecotone, ~28 km apart. The position of this biological boundary east of the Andes is controlled by the strength and position of the southern westerly winds, which constitute the sole source of precipitation throughout western Patagonia. Our results indicate that fires have occurred in the study region repeated times over the last ~13,000 years at bi- and tridecadal timescales. Sectors currently dominated by Patagonian steppe feature high frequency and low magnitude of local fires, and vice versa in humid forests. Climate-driven expansion of Nothofagus scrubland/woodland into steppe environments over the last ~4,200 years increased the magnitude and lowered the frequency of fire events, culminating with peak Nothofagus abundance, fire magnitude and frequency during the last millennium. We also detect divergences between lake-based vs. bog-based paleofire histories among paired sites located within the Patagonian steppe, ~12 km apart, which we attribute to local burning of the bog at times of lowered water table. This divergence suggests to us that bog-based vegetation and fire histories exacerbate a local, azonal, signal blurring extra-local or regional regimes, thus accounting for some discrepancies in the Quaternary paleovegetation/paleoclimate literature of southern Patagonia.
The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

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Molares, Soledad; Ladio, Ana

2011-01-01

Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60%) in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 ...
[Root canal treatment of mandibular first premolar with 4 root canals: a case report].

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Liu, Xin-yang; Zhan, Fu-Liang

2015-10-01

The mandibular first premolar can be considered one of the most challenging teeth to treat, due to the complexity of its root canal morphology and increased incidence of multiple canals. A case of endodontic treatment of a mandibular first premolar exhibiting a total of 4 distinct root canals and 4 apical foramina was described. Anatomic variation of root canal morphology should be considered in endodontic treatment to ensure a favorable healing outcome, and its identification could be enhanced by careful examination using a dental operating microscope. Obturation of root canals using a warm vertical compaction technique with a highly-radiopaque root canal sealer, such as AH Plus, after careful ultrasonic activated irrigation might allow the flow of sealer into the narrowed but unprepared part of the canal, thereby facilitating optimum chemo-mechanical debridement of the root canal system.
Peronism and political citizenship in the Patagonia: the look of the magazine Argentina Austral (1946-1955)

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Ruffini, Martha

2015-01-01

Desde 1929, y durante casi cuarenta años, en la Patagonia circuló la revista Argentina Austral. Esta continuidad fue facilitada por el sello original de la publicación que era propiedad de la empresa ganadera, comercial y naviera más importante del sur argentino: la Sociedad Anónima Importadora y Exportadora de la Patagonia, dirigida por la familia Braun-Menéndez Behety. La revista asumió una postura de demanda de ampliación de los derechos políticos de los habitantes del sur mientras expresa...
PTF 10fqs: A LUMINOUS RED NOVA IN THE SPIRAL GALAXY MESSIER 99

International Nuclear Information System (INIS)

Kasliwal, Mansi M.; Kulkarni, Shri R.; Quimby, Robert M.; Ofek, Eran O.; Arcavi, Iair; Gal-Yam, Avishay; Green, Yoav; Yaron, Ofer; Nugent, Peter; Jacobsen, Janet; Poznanski, Dovi; Fox, Derek B.; Howell, Jacob L.; Bradley Cenko, S.; Kleiser, Io; Bloom, Joshua S.; Miller, Adam; Li Weidong; Filippenko, Alexei V.; Starr, Dan

2011-01-01

The Palomar Transient Factory (PTF) is systematically charting the optical transient and variable sky. A primary science driver of PTF is building a complete inventory of transients in the local universe (distance less than 200 Mpc). Here, we report the discovery of PTF 10fqs, a transient in the luminosity 'gap' between novae and supernovae. Located on a spiral arm of Messier 99, PTF 10fqs has a peak luminosity of M r = -12.3, red color (g - r = 1.0), and is slowly evolving (decayed by 1 mag in 68 days). It has a spectrum dominated by intermediate-width Hα (∼930 km s -1 ) and narrow calcium emission lines. The explosion signature (the light curve and spectra) is overall similar to that of M85 OT2006-1, SN 2008S, and NGC 300 OT. The origin of these events is shrouded in mystery and controversy (and in some cases, in dust). PTF 10fqs shows some evidence of a broad feature (around 8600 A) that may suggest very large velocities (∼10,000 km s -1 ) in this explosion. Ongoing surveys can be expected to find a few such events per year. Sensitive spectroscopy, infrared monitoring, and statistics (e.g., disk versus bulge) will eventually make it possible for astronomers to unravel the nature of these mysterious explosions.
MULTIPLE SPINAL CANAL MENINGIOMAS

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Nandigama Pratap Kumar

2016-10-01

Full Text Available BACKGROUND Meningiomas of the spinal canal are common tumours with the incidence of 25 percent of all spinal cord tumours. But multiple spinal canal meningiomas are rare in compare to solitary lesions and account for 2 to 3.5% of all spinal meningiomas. Most of the reported cases are both intra cranial and spinal. Exclusive involvement of the spinal canal by multiple meningiomas are very rare. We could find only sixteen cases in the literature to the best of our knowledge. Exclusive multiple spinal canal meningiomas occurring in the first two decades of life are seldom reported in the literature. We are presenting a case of multiple spinal canal meningiomas in a young patient of 17 years, who was earlier operated for single lesion. We analysed the literature, with illustration of our case. MATERIALS AND METHODS In September 2016, we performed a literature search for multiple spinal canal meningiomas involving exclusively the spinal canal with no limitation for language and publication date. The search was conducted through http://pubmed.com, a wellknown worldwide internet medical address. To the best of our knowledge, we could find only sixteen cases of multiple meningiomas exclusively confined to the spinal canal. Exclusive multiple spinal canal meningiomas occurring in the first two decades of life are seldom reported in the literature. We are presenting a case of multiple spinal canal meningiomas in a young patient of 17 years, who was earlier operated for solitary intradural extra medullary spinal canal meningioma at D4-D6 level, again presented with spastic quadriparesis of two years duration and MRI whole spine demonstrated multiple intradural extra medullary lesions, which were excised completely and the histopathological diagnosis was transitional meningioma. RESULTS Patient recovered from his weakness and sensory symptoms gradually and bladder and bowel symptoms improved gradually over a period of two to three weeks. CONCLUSION Multiple
Eastern Andean environmental and climate synthesis for the last 2000 years BP from terrestrial pollen and charcoal records of Patagonia

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Sottile, G. D.; Echeverria, M. E.; Mancini, M. V.; Bianchi, M. M.; Marcos, M. A.; Bamonte, F. P.

2015-06-01

The Southern Hemisphere Westerly Winds (SWW) constitute an important zonal circulation system that dominates the dynamics of Southern Hemisphere mid-latitude climate. Little is known about climatic changes in the Southern South America in comparison to the Northern Hemisphere due to the low density of proxy records, and adequate chronology and sampling resolution to address environmental changes of the last 2000 years. Since 2009, new pollen and charcoal records from bog and lakes in northern and southern Patagonia at the east side of the Andes have been published with an adequate calibration of pollen assemblages related to modern vegetation and ecological behaviour. In this work we improve the chronological control of some eastern Andean previously published sequences and integrate pollen and charcoal dataset available east of the Andes to interpret possible environmental and SWW variability at centennial time scales. Through the analysis of modern and past hydric balance dynamics we compare these scenarios with other western Andean SWW sensitive proxy records for the last 2000 years. Due to the distinct precipitation regimes that exist between Northern (40-45° S) and Southern Patagonia (48-52° S) pollen sites locations, shifts on latitudinal and strength of the SWW results in large changes on hydric availability on forest and steppe communities. Therefore, we can interpret fossil pollen dataset as changes on paleohydric balance at every single site by the construction of paleohydric indices and comparison to charcoal records during the last 2000 cal yrs BP. Our composite pollen-based Northern and Southern Patagonia indices can be interpreted as changes in latitudinal variation and intensity of the SWW respectively. Dataset integration suggest poleward SWW between 2000 and 750 cal yrs BP and northward-weaker SWW during the Little Ice Age (750-200 cal yrs BP). These SWW variations are synchronous to Patagonian fire activity major shifts. We found an in phase
Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

International Nuclear Information System (INIS)

Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul

2001-01-01

To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of
Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

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Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul [Sungkyunkwan Univ., School of Medicine, Seoul (Korea, Republic of)

2001-12-01

To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of
Formas terminales de Hippidion (Mammalia, Perissodactyla de los yacimientos del Pleistoceno Tardio-Holoceno de la Patagonia (Argentina y Chile

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Prado, J. L.

1987-04-01

Full Text Available The present study is a revision of the terminal forms of the South-American horses coming from the archeological sites of Patagonia. They are compared with those from the Northwest of Argentine. The study also includes paleoenvironmental and cronological related aspects.El presente estudio comprende una revisión de las formas terminales de caballos sudamericanos recuperados de sitios arqueológicos de la Patagonia. Se comparan con las formas del noroeste argentino. Incluye aspectos paleoambientales y cronológicos relacionados.
Trace elements deposition in the Tierra del Fuego region (south Patagonia) by using lichen transplants after the Puyehue-Cordón Caulle (north Patagonia) volcanic eruption in 2011.

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Conti, Marcelo Enrique; Jasan, Raquel; Finoia, Maria Grazia; Iavicoli, Ivo; Plá, Rita

2016-04-01

Lichen Usnea barbata transplants were tested as a biomonitor of atmospheric deposition in an apparently pristine environment that is Tierra del Fuego region (Patagonia, Argentina). The present survey is connected with the volcanic eruption that started in north Patagonia on June 4, 2011 from the Puyehue-Cordón Caulle volcano, Chile (north Patagonia, at 1700 km of distance of our sampling sites). Lichens were collected in September 2011 (one month of exposure) and September 2012 (1 year of exposure) in 27 sites covering the northern region of the province where trees are not present. The atmospheric deposition of 27 elements by using Neutron Activation Analysis (NAA) was determined in the collected samples. The first aim of the study was to evaluate the influence of the volcanic eruption on the regional atmospheric deposition comparing our results with baseline data we determined in U. barbata in 2006 in the same sites. The second aim was to test possible patterns of bioaccumulation between the two sampling campaigns after the volcanic eruption. With respect to 2006 baseline levels, we found significant higher levels for As, Ba, Co, Cr, Cs, Na, Sb and U in lichens collected after 1 month of exposure (first sampling campaign--2011). Between the two sampling campaigns (2011-2012) after the eruption, lichens reflected the natural contamination by volcanic ashes with significantly higher median levels of Br, Cr, Fe, K, Na, Sc, and Se. Results confirmed the very good aptitude of U. barbata to reflect the levels of elements in the environment at global scale and to reflect the volcanic emissions at distant places. Volcanic eruptions cause the emission in the atmosphere of elevated levels of particulate matter. In this regard, our findings demonstrate the importance to evaluate the metal composition of the particles to avoid possible health effects.
Scanning electron microscopy investigation of canal cleaning after canal preparation with nickel titanium files

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Živković Slavoljub

2010-01-01

Full Text Available Introduction. Root canal preparation is the most important phase of endodontic procedure and it consists of adequate canal space cleaning and shaping. In recent years, rotary instruments and techniques have gained importance because of the great efficacy, speed and safety of the preparation procedure. Objective. The aim of this research was to investigate the influence of different NiTi files on the canal wall cleaning quality, residual dentine debris and smear layer. Methods. The research was conducted on extracted human teeth in vitro conditions. Teeth were divided in 7 main groups depending on the kind of instruments used for root canal preparation: ProTaper, GT, ProFile, K-3, FlexMaster, hand ProTaper and hand GT. Root canal preparation was accomplished by crown-down technique. Prepared samples were assessed on scanning electron microscopy JEOL, JSM-6460 LV. The evaluation of dentine debris was done with 500x magnification, and the evaluation of smear layer with 1,000 times magnification. Quantitive assessment of dentine debris and smear layer was done according to the criteria of Hulsmann. Results. The least amount of debris and smear layer has been found in canals shaped with ProFile instruments, and the largest amount in canals shaped with FlexMaster instruments. Canal cleaning efficacy of hand GT and ProTaper files has been similar to cleaning efficacy of rotary NiTi files. Statistic analysis has shown a significant difference in amount of dentine debris and smear layer on the canal walls between sample groups shaped with different instruments. Conclusion. Completely clean canals have not been found in any tested group of instruments. The largest amount of debris and smear layer has been found in the apical third of all canals. The design and the type of endodontic instruments influence the efficacy of the canal cleaning.

Curved canals: Ancestral files revisited

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Jain Nidhi

2008-01-01

Full Text Available The aim of this article is to provide an insight into different techniques of cleaning and shaping of curved root canals with hand instruments. Although a plethora of root canal instruments like ProFile, ProTaper, LightSpeed ® etc dominate the current scenario, the inexpensive conventional root canal hand files such as K-files and flexible files can be used to get optimum results when handled meticulously. Special emphasis has been put on the modifications in biomechanical canal preparation in a variety of curved canal cases. This article compiles a series of clinical cases of root canals with curvatures in the middle and apical third and with S-shaped curvatures that were successfully completed by employing only conventional root canal hand instruments.
Análisis de sistema de conversores fluido-dinámicos de energía renovable para la Patagonia Austral de Argentina

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Carlos Victor Manuel Labriola

2014-06-01

Full Text Available El potencial de energía en mares y océanos se puede clasificar de distintas formas, por ejemplo: * La energía de las mareas ó Mareomotriz * La energía de las corrientes marinas * La energía de las olas ó Undimotriz * La energía térmica oceánica (OTEC. De estas formas de energía oceánica, tres son posibles en la zona Atlántica de nuestra Patagonia Austral, la Mareomotriz, la Undimotriz y la de corrientes marinas. La Energía Mareomotriz se da desde Viedma hasta Tierra del Fuego con amplitudes de mareas de 4m hasta 20m, la Energía de las Olas se da en la costa de Chubut y Santa Cruz con potenciales de 10 a 30kW/m lineal de frente de ola y el aprovechamiento de las corrientes marinas se puede dar en lugares puntuales como ser la desembocadura del río Deseado o la de Río Gallegos. Para estas Fuentes de Energía se está realizando un banco de pruebas de modelos conversores de las mismas a Energía Eléctrica, en la Unidad Académica Caleta Olivia (UACO de la Universidad Nacional de la Patagonia Austral (UNPA. Este banco dispondrá de dos canales de ensayos hidrodinámicos uno para energía de las corrientes marinas y otro para las olas. El primero dispondrá de una bomba de circulación con velocidad de fluido variable entre 0 y 4m/s. El banco para olas tendrá un sistema de batido del agua para producir ondas de amplitud y período variable. Además se están dimensionando dos modelos de conversores de energía oceánica. Uno es una turbina, tipo eólica sumergida y el otro modelo es de tubo electromecánico oscilante como conversor energético de las olas.
Insectos acuáticos de la Meseta del Somuncura, Patagonia, Argentina. Inventario preliminar Aquatic insects from Somuncura plateau, Patagonia, Argentina. Preliminary inventory

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Javier Muzón

2005-12-01

Full Text Available RESUMEN. Se brinda un inventario preliminar de los insectos acuáticos de la Meseta del Somuncura y su área de influencia (Patagonia, Argentina realizado sobre la base de colecciones y registros previos de especies pertenecientes a los órdenes Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (familias Ceratopogonidae, Culicidae y Psychodidae y Coleoptera. Se han relevado diversos tipos de ambientes en 14 localidades. El número de especies registrado asciende a 78, agrupadas en 51 géneros y 26 familias, de las cuales 33 se citan por primera vez del área. De los taxa registrados 83% de los géneros corresponden a grupos de amplia distribución (neotropicales, americanos o cosmopolitas, mientras que 41% de las especies presentan una distribución patagónica o andina.ABSTRACT. A preliminary inventory of the aquatic insects from the Somuncura plateau and its area of influence (Patagonia, Argentina is presented. It was done on the basis of the study of collections and previous records of species belonging to the orders Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (families Ceratopogonidae, Culicidae, and Psychodidae and Coleoptera. Different kinds of environments were surveyed in 14 localities. Seventy eigth species grouped in 51 genera and 26 families were registered, and 33 species are new records for the area. Eighty three % of the registered genera are widely distributed (neotropical, american or cosmopolitan, while 41 % of the species exhibit patagonic or andean distribution.
Combined U-Pb SHRIMP and Hf isotope study of the Late Paleozoic Yaminué Complex, Rio Negro Province, Argentina: Implications for the origin and evolution of the Patagonia composite terrane

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Carlos J. Chernicoff

2013-01-01

Combining geological and isotope data, as well as geophysical models, we identify the Yaminué Complex within the La Esperanza-Yaminué crustal block flanked by two other, distinct crustal blocks: the Eastern block which forms part of the Patagonia terrane sensu stricto, located in the eastern Patagonian region, and the Western block forming part of the Southern Patagonia terrane. Their origins and timing of amalgamation to form the Patagonia composite terrane are also discussed.
Endoscopic root canal treatment.

Science.gov (United States)

Moshonov, Joshua; Michaeli, Eli; Nahlieli, Oded

2009-10-01

To describe an innovative endoscopic technique for root canal treatment. Root canal treatment was performed on 12 patients (15 teeth), using a newly developed endoscope (Sialotechnology), which combines an endoscope, irrigation, and a surgical microinstrument channel. Endoscopic root canal treatment of all 15 teeth was successful with complete resolution of all symptoms (6-month follow-up). The novel endoscope used in this study accurately identified all microstructures and simplified root canal treatment. The endoscope may be considered for use not only for preoperative observation and diagnosis but also for active endodontic treatment.
LA PATAGONIA ORIENTAL SEGÚN UNA REAL CÉDULA de 1570 MENOSPRECIADA POR LA HISTORIOGRAFÍA CHILENA

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MANUEL RAVEST MORA

2005-12-01

Full Text Available Versa este trabajo sobre la Real Cédula de Felipe II que, en 1570, fusionó parte de la Patagonia Oriental con la Provincia del Río de la Plata, origen de la República Argentina, donde, al parecer, supieron del documento treinta años después de finalizado el debate con Chile acerca de los derechos al extremo meridional de América. Descubierta por un diplomático chileno, que informó de ella a su Cancillería en 1876 y la mencionó en un libro publicado en 1903, ha sido sistemáticamente ignorada por los escritores chilenos. Examina este trabajo las posibles causas de ese silencio historiográfico, como también las rectificaciones que la RC introduce en la tesis clásica o fundacional de Chile, formulada a mediados del XIX por Miguel Luis Amunátegui, según la cual ese país siempre ejerció jurisdicción sobre la totalidad de la Patagonia Oriental desde 1554This work deals with a 1570 Phillip the II Decree that fused a section of Atlantic Patagonia with the Rio de la Plata Province, origin of late Argentine Republic, who, apparently, learned about it thirty years after ended the discussion held with Chile in respect the rights of each country towards the southern extreme of America. Found by a chilean diplomat, who informed his Ministry of Foreign Affairs in 1876 and wrote about the document in a book published in 1903, it has been systematically ignored by chilean scholars. The work examines the possible causes for this historiographyc silence, and the rectifications that the Royal Decree introduces in the classical chilean thesis about Patagonia, enounced by Miguel Luis Amunategui in middle XIX century, according to which that whole territory always belonged to Chile since 1554
Decreased levels of matrix metalloproteinase-2 in root-canal exudates during root canal treatment.

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Pattamapun, Kassara; Handagoon, Sira; Sastraruji, Thanapat; Gutmann, James L; Pavasant, Prasit; Krisanaprakornkit, Suttichai

2017-10-01

To determine the matrix metalloproteinase-2 (MMP-2) levels in root-canal exudates from teeth undergoing root-canal treatment. The root-canal exudates from six teeth with normal pulp and periradicular tissues that required intentional root canal treatment for prosthodontic reasons and from twelve teeth with pulp necrosis and asymptomatic apical periodontitis (AAP) were sampled with paper points for bacterial culture and aspirated for the detection of proMMP-2 and active MMP-2 by gelatin zymography and the quantification of MMP-2 levels by ELISA. By gelatin zymography, both proMMP-2 and active MMP-2 were detected in the first collection of root-canal exudates from teeth with pulp necrosis and AAP, but not from teeth with normal pulp, and their levels gradually decreased and disappeared at the last collection. Consistently, ELISA demonstrated a significant decrease in MMP-2 levels in the root-canal exudates of teeth with pulp necrosis and AAP following root canal procedures (papical lesions, similar to the clinical application of MMP-8 as a biomarker. Copyright © 2017 Elsevier Ltd. All rights reserved.
Distribución geográfica, historia natural y conservación del hurón menor Galictis cuja (Carnivora: Mustelidae en la Patagonia central, Argentina Geographic distribution, natural history and conservation of the lesser grison Galictis cuja (Carnivora: Mustelidae from Central Patagonia, Argentina

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Marcelo Carrera

2012-12-01

Full Text Available El hurón menor, Galictis cuja, tiene una amplia distribución en el territorio patagónico extraandino, aunque sus registros puntuales son escasos. Este trabajo se desarrolló en la provincia del Chubut, Patagonia Central, Argentina. Aquí se aportan nuevas localidades de registro de G. cuja para esta región; se discuten aspectos de su distribución geográfica y conservación en el Área Natural Protegida Península Valdés (ANP-PV; Patrimonio Natural de la Humanidad y brevemente se explora la representación de G. cuja en los ensambles de carnívoros del ANP-PV desde el Holoceno tardío hasta la actualidad. Se adicionaron 18 nuevos registros de G. cuja en Patagonia central. Se detectó un conflicto entre los pobladores y hurones, que motiva la caza de estos últimos. Se verificó un aparente incremento de abundancia de G. cuja en los últimos miles de años, concomitante con la extinción regional o dramática disminución de Lyncodon patagonicus (Carnivora, Mustelidae.The Lesser Grison, Galictis cuja, is a species widely distributed in extra-Andean Patagonia, although its records are scarce. This work was carried out in Chubut province, Central Patagonia, Argentina. Here we report new occurrence localities of G. cuja for this region; we discuss aspects of their geographical distribution and conservation in the Área Natural Protegida Península Valdés (ANP-PV; World Heritage Site and briefly explores the representation of G. cuja in carnivore assemblages of ANP-PV, since the late Holocene to the present. We added 18 new records of G. cuja in Central Patagonia. We detected a conflict between the rural residents and the Lesser Grison, which motivates the hunting of the latter. There was an apparent increase in abundance of G. cuja in the last thousands of years, concomitant with regional extinction or dramatic reduction of Lyncodon patagonicus (Carnivora, Mustelidae.
THE PROGENITOR OF SUPERNOVA 2011dh/PTF11eon IN MESSIER 51

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Van Dyk, Schuyler D. [Spitzer Science Center/Caltech, Pasadena CA 91125 (United States); Li, Weidong; Cenko, S. Bradley; Silverman, Jeffrey M.; Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Kasliwal, Mansi M.; Horesh, Assaf; Ofek, Eran O.; Quimby, Robert M.; Kulkarni, Shrinivas R. [Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States); Kraus, Adam L. [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Arcavi, Iair; Gal-Yam, Avishay; Yaron, Ofer; Polishook, David, E-mail: vandyk@ipac.caltech.edu [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel)

2011-11-10

We have identified a luminous star at the position of supernova (SN) 2011dh/PTF11eon, in pre-SN archival, multi-band images of the nearby, nearly face-on galaxy Messier 51 (M51) obtained by the Hubble Space Telescope with the Advanced Camera for Surveys. This identification has been confirmed, to the highest available astrometric precision, using a Keck-II adaptive-optics image. The available early-time spectra and photometry indicate that the SN is a stripped-envelope, core-collapse Type IIb, with a more compact progenitor (radius {approx} 10{sup 11} cm) than was the case for the well-studied SN IIb 1993J. We infer that the extinction to SN 2011dh and its progenitor arises from a low Galactic foreground contribution, and that the SN environment is of roughly solar metallicity. The detected object has absolute magnitude M{sup 0}{sub V} Almost-Equal-To -7.7 and effective temperature {approx}6000 K. The star's radius, {approx}10{sup 13} cm, is more extended than what has been inferred for the SN progenitor. We speculate that the detected star is either an unrelated star very near the position of the actual progenitor, or, more likely, the progenitor's companion in a mass-transfer binary system. The position of the detected star in a Hertzsprung-Russell diagram is consistent with an initial mass of 17-19 M{sub Sun }. The light of this star could easily conceal, even in the ultraviolet, the presence of a stripped, compact, very hot ({approx}10{sup 5} K), nitrogen-rich Wolf-Rayet star progenitor.
Flavonols, alkaloids, and antioxidant capacity of edible wild berberis species from patagonia.

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Ruiz, Antonieta; Zapata, Moises; Sabando, Constanza; Bustamante, Luis; von Baer, Dietrich; Vergara, Carola; Mardones, Claudia

2014-12-24

There are 20 species of the Berberidaceae family described in Chile, whose fruits are edible and show high anthocyanin and hydroxycinnamic acid levels. Berberis microphylla G. Forst, commonly known as calafate, is the most extensively distributed. Flavonols and alkaloids in seed, pulp, skin, and whole calafate berry extracts and other Berberis were studied using HPLC-DAD-ESI-MS/MS and HPLC with fluorescence detector. Berry samples from different locations in Chilean Patagonia, including different phenological stages, were systematically addressed. Results were compared with other organs of the plant and with other Berberis species. Total flavonol concentration in calafate (n = 65) was 1.33 ± 0.54 μmol/g. Glycosyl metabolites of quercetin and isorhamnetin were the most abundant. Similar profiles were observed in calafate from distinct locations, but important differences were observed for the other edible Berberis species. Calafate pulp and skin have higher flavonol concentrations than seeds, and the maturation process reduced its levels. TEACCUPRAC and TEACABTS of whole calafate extracts and fractions are also explored. Finally, only berberine was detected in the fruit (0.001%), mainly in seeds. Results contribute to the promotion of this berry as a superfruit from Patagonia.
Little Ice Age advance and retreat of Glaciar Jorge Montt, Chilean Patagonia

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A. Rivera

2012-03-01

Full Text Available Glaciar Jorge Montt (48°20' S/73°30' W, one of the main tidewater glaciers of the Southern Patagonian Icefield (SPI, has experienced the greatest terminal retreat observed in Patagonia during the past century, with a recession of 19.5 km between 1898 and 2011. This retreat has revealed trees laying subglacially until 2003. These trees were dated using radiocarbon, yielding burial ages between 460 and 250 cal yrs BP. The presence of old growth forest during those dates indicates that Glaciar Jorge Montt was upvalley of its present position before the commonly recognized Little Ice Age (LIA period in Patagonia. The post-LIA retreat was most likely triggered by climatically induced changes during the 20th century; however, Glaciar Jorge Montt has responded more dramatically than its neighbours. The retreat of Jorge Montt opened a 19.5 km long fjord since 1898, which reaches depths in excess of 390 m. The bathymetry is well correlated with glacier retreat rates, suggesting that dynamic responses of the glacier are at least partially connected to near buoyancy conditions at the ice front, resulting in high calving fluxes, accelerating thinning rates and rapid ice velocities.
Design of canals

CERN Document Server

Swamee, P K

2015-01-01

The book presents firsthand material from the authors on design of hydraulic canals. The book discusses elements of design based on principles of hydraulic flow through canals. It covers optimization of design based on usage requirements and economic constraints. The book includes explicit design equations and design procedures along with design examples for varied cases. With its comprehensive coverage of the principles of hydraulic canal design, this book will prove useful to students, researchers, and practicing engineers. End-of-chapter pedagogical elements make it ideal for use in graduate courses on hydraulic structures offered by most civil engineering departments across the world.
Chondrichthyans of the San Matías Gulf, Patagonia, Argentina Los condrictios del Golfo San Matías, Patagonia, Argentina

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María R PERIER

2011-12-01

Full Text Available The San Matías Gulf (SMG; 41°- 42° S; 64°- 65° W is the largest gulf in Northern Patagonia, Argentina. Up to date, the chondrichthyan fauna of this area has not been reported. Therefore, the aim of this work is to provide a list with species presence and biological characteristics of the chondrichthyans recorded in SMG during the last 30 years. A total of 13 sharks distributed in 11 families, 19 skates and rays distributed in six families, and one holocephalan have been so far recorded in SMG. From the zoogeographical point of view, this chondrichthyan fauna is a mixed assemblage of species typically found in the Argentinean and Magellanean Provinces. The holocephalan Callorhinchus callorynchus is the most landed chondricthyan of the local fishery. With it, five sharks and seven skates are also exploited.El Golfo San Matías (SMG; 41°- 42° S - 64°-65° O se encuentra ubicado en el norte de la Patagonia, Argentina. Hasta la fecha no se cuentan con reportes de la fauna de condrictios de esta zona. Por lo tanto, el objetivo de este trabajo es proporcionar una lista de la presencia y las características biológicas de los condrictios registrados en el SMG durante los últimos 30 años. Un total de 13 tiburones distribuidos en 11 familias, 19 batoideos distribuidos en seis familias y un holocefalo han sido reportados para la zona. Desde el punto de vista zoogeográfico, el SMG presenta un ensamble de especies pertenecientes a las Provincias Magallánica y Argentina. El holocefalo Callorhinchus callorynchus es el condrictio más desembarcado de la pesquería local. Con menor importancia son explotadas comercialmente, cinco especies de tiburones y siete de rayas.
An evaluation of canal curvature at the apical one third in type II mesial canals of mandibular molars

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Hye-Rim Yun

2012-05-01

Full Text Available Objectives The purpose of this study was to evaluate the buccolingual curvature at the apical one third in type II mesial canals of mandibular molars using the radius and angle of curvature. Materials and Methods Total 100 mandibular molars were selected. Following an endodontic access in the teeth, their distal roots were removed. #15 H- or K-files (Dentsply Maillefer were inserted into the mesiobuccal and mesiolingual canals of the teeth. Radiographs of the teeth were taken for the proximal view. Among them, type II canals were selected and divided into two subgroups, IIa and IIb. In type IIa, two separate canals merged into one canal before reaching the apex and in type IIb, two separate canals merged into one canal within the apical foramen. The radius and angle of curvature of specimens were examined. Results In type II, mean radius of curvature in mesiolingual and mesiobuccal canals were 2.82 mm and 3.58 mm, respectively. The radius of the curvature of mesiolingual canals were significantly smaller than that of mesiobuccal canals in type II, and especially in type IIa. However, there were no statistically significant differences in radius of curvature between mesiobuccal and mesiolingual canals in type IIb and there were no significant differences in angle of curvature between type IIa and IIb. Conclusion In this study, type II mesial canals of mandibular molars showed severe curvature in the proximal view. Especially, mesiolingual canals of type IIa had more abrupt curvature than mesiobuccal canals at the apical one third.
Osmolarity and root canal antiseptics.

Science.gov (United States)

Rossi-Fedele, G; Guastalli, A R

2014-04-01

Antiseptics used in endodontics for disinfection purposes include root canal dressings and irrigants. Osmotic shock is known to cause the alteration of microbial cell viability and might have a role in the mechanism of action of root canal antiseptics. The aim of this review was to determine the role of osmolarity on the performance of antiseptics in root canal treatment. A literature search using the Medline electronic database was conducted up to 30 May 2013 using the following search terms and combinations: 'osmolarity AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmolality AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmotic AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmosis AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; sodium chloride AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm'. Publications were included if the effects of osmolarity on the clinical performance of antiseptics in root canal treatment were stated, if preparations with different osmolarities values were compared and if they were published in English. A hand search of articles published online, 'in press' and 'early view', and in the reference list of the included papers was carried out following the same criteria. A total of 3274 publications were identified using the database, and three were included in the review. The evidence available in endodontics suggests a possible role for hyperosmotic root canal medicaments as disinfectants, and that there is no influence of osmolarity on the tissue dissolution capacity of sodium hypochlorite. There are insufficient data to obtain a sound conclusion regarding the role of hypo-osmosis in root canal disinfection, or osmosis in any further desirable
[Continuous observation of canal aberrations in S-shaped simulated root canal prepared by hand-used ProTaper files].

Science.gov (United States)

Xia, Ling-yun; Leng, Wei-dong; Mao, Min; Yang, Guo-biao; Xiang, Yong-gang; Chen, Xin-mei

2009-08-01

To observe the formation of canal aberrations in S-shaped root canals prepared by every file of hand-used ProTaper. Fifteen S-shaped simulated resin root canals were selected. Each root canal was prepared by every file of hand-used ProTaper following the manufacturer instruction. The images of canals prepared by S1, S2, F1, F2 and F3 were taken and stored, which were divided into group S1, S2, F1, F2 and F3. One image of canal unprepared was superposed with the images of the same root canal in these five groups respectively to observe the types and number of canal aberrations, which included unprepared area, danger zone, ledge, elbow, zip and perforation. SPSS12.0 software pakage was used for Fisher's exact probabilities in 2x2 table. Unprepared area decreased following preparation by every file of ProTaper, but it still existed when the canal preparation was finished. The incidence of danger zone, elbow and zip in group F1 was 15/15, 11/15, 4/15, respectively, which was significantly higher than that in group S2(2/15,0,0) (PProTaper.The presence of unprepared area suggests that it is essential to rinse canal abundantly during complicated canal preparation and canal antisepsis after preparation.
Anatomic study on mental canal and incisive nerve canal in interforaminal region in Chinese population.

Science.gov (United States)

Xu, Yun; Suo, Ning; Tian, Xiufen; Li, Fei; Zhong, Guangxin; Liu, Xiaoran; Bao, Yongxing; Song, Tao; Tian, Hua

2015-08-01

This study was aimed to detect the positions of mental canal and incisive nerve canal as well as the prolongation of mandibular canal in interforaminal region in Chinese population to supply the reference data of the surgical safe zone in chin for clinicians. A total of 80 formalin-fixed semi-mandibles of Chinese adult cadavers were dissected, the positions and courses of mental canal and incisive nerve canal as well as the prolongation of mandibular canal in interforaminal region were measured. The mental foramina were present in all cases (100 %), and most of them were located below 2nd premolar (58.75 %). Accessory mental foramina were observed in 5 %. The anterior end of mandibular canal, extending along the course of 7.37 ± 1.10 mm above the lower border of mandible to interforaminal region about 3.54 ± 0.70 mm medial to the mental foramen, most often ended below between the two premolars (73.75 %), where it continued as the incisive nerve canal (100 %) and the mental canal (96.25 %). Mental canal, with the wall formed by compact bone, being 2.60 ± 0.60 mm in diameter and 4.01 ± 1.20 mm in length, opened into mental foramen. Incisive nerve canal, with the wall formed by thin compact bone and/or partly or completely by spongy bone, being 1.76 ± 0.27 mm in diameter and 24.87 ± 2.23 mm in length, extended to the incisor region along the course of 9.53 ± 1.43 mm above the lower border of mandible, and most often ended below the lateral incisor (70.00 %). This research recommended for chin operations in Chinese population: the surgical safe zone could be set in the region about over 4 mm anterior to the mental foramen, and over 12 mm above inferior border of mandible for anterior alveolar surgery, or within 9 mm above inferior border of mandible for genioplasty.
Periapical repair after root canal filling with different root canal sealers.

Science.gov (United States)

Tanomaru-Filho, Mário; Tanomaru, Juliane Maria Guerreiro; Leonardo, Mario Roberto; da Silva, Lea Assed Bezerra

2009-01-01

The aim of this study was to evaluate periapical repair after root canal filling with different endodontic sealers. Sixty-four root canals from dog s teeth were filled, divided into 4 groups (n=16). Root canals were instrumented with K-type files and irrigated with 1% sodium hypochlorite solution. Root canals were filled in the same session by active lateral condensation of the cones and sealers: Intrafill, AH Plus, Roeko Seal and Resilon/Epiphany System. After 90 days, the animals were euthanized and the tissues to be evaluated were processed and stained with hematoxylin and eosin. For histopathological analysis, the following parameters were evaluated: inflammatory process, mineralized tissue resorption, and apical mineralized tissue deposition. Histopathological analysis demonstrated that Intrafill had less favorable results in terms of apical and periapical repair, compared to the other sealers (p0.05). In conclusion, AH Plus and the materials Roeko Seal and Epiphany are good options for clinical use in Endodontics.
A comparative evaluation of the increase in root canal surface area and canal transportation in curved root canals by three rotary systems: A cone-beam computed tomographic study

Science.gov (United States)

Prasanthi, Nalam NVD; Rambabu, Tanikonda; Sajjan, Girija S; Varma, K Madhu; Satish, R Kalyan; Padmaja, M

2016-01-01

Aim: The aim of this study was to measure the increase in root canal surface area and canal transportation after biomechanical preparation at 1, 3, and 5 mm short of the apex with three different rotary systems in both continuous rotary and reciprocating rotary motions. Materials and Methods: Sixty freshly extracted human mandibular molars with mesial root canal curvatures between 20° and 30° were included in the study. Teeth were randomly distributed into three groups (n = 20). Biomechanical preparations were done in all the mesial canals. In Group 1, instrumentation was done with ProTaper universal rotary files, Group 2, with K3XF rotary files, and Group 3, with LSX rotary files. Each group was further subdivided into subgroups A and B (n = 10) where instrumentation was done by continuous rotary and reciprocating rotary techniques, respectively. Increase in root canal surface area and canal transportation was measured using the preoperative and postoperative cone-beam computed tomography scans. Statistical Analysis: The data were analyzed by one-way ANOVA followed by Tukey pairwise multiple comparison tests. Results: Increase in root canal surface area was significantly more (P 0.05) in increase of root canal surface area and canal transportation between continuous rotary and reciprocating rotary techniques for ProTaper Universal, K3XF and LSX groups. Conclusion: LSX rotary system showed minimal increase of root canal surface area and minimal canal transportation when compared to ProTaper and K3XF rotary systems. PMID:27656062
The uranium potential of the continental Cretaceous of Patagonia

International Nuclear Information System (INIS)

Olsen, H.; Berizzo, J.

1980-01-01

The geological features of the fluvial sedimentation of the Cretaceous of Patagonia - the Grupo Chubut Formation in the provinces of Chubut and Santa Cruz, underlined this environment as one of high favourability for discovering uranium deposits. The area has been explored by the CNEA who found two outstanding levels of fluvial sediments that are today the target of further studies to find new deposits. The general geological features are given, together with the results of the exploration up to date, distribution of radiometric anomalies, deposits discovered and an estimation of the uraniferous potential of the Formation. (author)

Posterior semicircular canal dehiscence: a morphologic cause of vertigo similar to superior semicircular canal dehiscence

International Nuclear Information System (INIS)

Krombach, G.A.; Schmitz-Rode, T.; Haage, P.; Guenther, R.W.; DiMartino, E.; Prescher, A.; Kinzel, S.

2003-01-01

Heading Abstract.The aim of this study was to assess imaging findings of posterior semicircular dehiscence on computed tomography and to evaluate incidence of posterior and superior semicircular canal dehiscence in patients presenting with vertigo, sensorineuronal hearing loss or in a control group without symptoms related to the inner ear. Computed tomography was performed in 507 patients presenting either with vertigo (n=128; 23 of these patients suffered also from sensorineuronal hearing loss), other symptoms related to the inner ear, such as hearing loss or tinnitus (n=183) or symptoms unrelated to the labyrinth (n=196). All images were reviewed for presence of dehiscence of the bone, overlying the semicircular canals. Twenty-nine patients had superior semicircular canal dehiscence. Of these patients, 83% presented with vertigo, 10% with hearing loss or tinnitus and the remaining 7% with symptoms unrelated to the inner ear. In 23 patients dehiscence of the posterior semicircular canal was encountered. Of these patients, 86% presented with vertigo, 9% with hearing loss or tinnitus and 5% with symptoms unrelated to the inner ear. Defects of the bony overly are found at the posterior semicircular canal, in addition to the recently introduced superior canal dehiscence syndrome. Significant prevalence of vertigo in these patients suggests that posterior semicircular canal dehiscence can cause vertigo, similar to superior semicircular canal dehiscence. (orig.)
Posterior semicircular canal dehiscence: a morphologic cause of vertigo similar to superior semicircular canal dehiscence

Energy Technology Data Exchange (ETDEWEB)

Krombach, G A; Schmitz-Rode, T; Haage, P; Guenther, R W [Department of Diagnostic Radiology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); DiMartino, E [Department of Otorhinolaryngology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Prescher, A [Department of Anatomy, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Kinzel, S [Department of Experimental Veterinarian Medicine, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany)

2003-06-01

Heading Abstract.The aim of this study was to assess imaging findings of posterior semicircular dehiscence on computed tomography and to evaluate incidence of posterior and superior semicircular canal dehiscence in patients presenting with vertigo, sensorineuronal hearing loss or in a control group without symptoms related to the inner ear. Computed tomography was performed in 507 patients presenting either with vertigo (n=128; 23 of these patients suffered also from sensorineuronal hearing loss), other symptoms related to the inner ear, such as hearing loss or tinnitus (n=183) or symptoms unrelated to the labyrinth (n=196). All images were reviewed for presence of dehiscence of the bone, overlying the semicircular canals. Twenty-nine patients had superior semicircular canal dehiscence. Of these patients, 83% presented with vertigo, 10% with hearing loss or tinnitus and the remaining 7% with symptoms unrelated to the inner ear. In 23 patients dehiscence of the posterior semicircular canal was encountered. Of these patients, 86% presented with vertigo, 9% with hearing loss or tinnitus and 5% with symptoms unrelated to the inner ear. Defects of the bony overly are found at the posterior semicircular canal, in addition to the recently introduced superior canal dehiscence syndrome. Significant prevalence of vertigo in these patients suggests that posterior semicircular canal dehiscence can cause vertigo, similar to superior semicircular canal dehiscence. (orig.)
Unpredictable Root Canal Morphology: Expect the Unexpected

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Sohez J Makani

2015-01-01

Full Text Available Background: A maxillary first molar with more than four canals is an interesting example of anatomic variations, especially when two of these canals are detected, with separate apical foramen in the distal root. The inability to locate the unexpected canals of various anatomical configuration and subsequently treat them , may lead to therapeutic failures. Endodontic retreatment is usually the modality of choice in such cases. This report describes a case of a maxillary first molar with five canals (two mesial canals in mesial root, two distal canals in two distal roots and a palatal canal in palatal root. Additionally it shows a rare anatomic configuration and emphasizes the importance of identifying additional canals.
Climate and sea-level changes across a shallow marine Cretaceous–Palaeogene boundary succession in Patagonia, Argentina

NARCIS (Netherlands)

Vellekoop, Johan; Holwerda, Femke; Prámparo, Mercedes B.; Willmott, Veronica; Schouten, Stefan; Cúneo, Nestor R.; Scasso, Roberto A.; Brinkhuis, Henk

2017-01-01

Upper Maastrichtian to lower Paleocene, coarse-grained deposits of the Lefipán Formation in Chubut Province, (Patagonia, Argentina) provide an opportunity to study environmental changes across the Cretaceous–Palaeogene (K–Pg) boundary in a shallow marine depositional environment. Marine
Do coastal fronts influence bioerosion patterns along Patagonia? Late Quaternary ichnological tools from Golfo San Jorge

Science.gov (United States)

Richiano, Sebastián; Aguirre, Marina; Castellanos, Ignacio; Davies, Karen; Farinati, Ester

2017-12-01

Late Quaternary marine molluscan skeletal concentrations from Argentina constitute a remarkable record of variations in palaeoceanographical conditions during interglacial times (mainly ca. 125 ka to present). Particularly, the Golfo San Jorge coastal area represents an extraordinary geographical zone to target from different points of view, mainly due to its linkage between northern and southern Patagonia, characterized by particular and contrasting physico-chemical conditions with direct consequences for littoral marine communities, determining their composition and structure. Among varied biological activities controlled by different environmental factors (i.e., substrate nature, sedimentation rates, water depth, sea surface temperature, salinity, nutrients-productivity), bioerosion traces can provide palaeoenvironmental evidence with important implications for palaeoclimate interpretations. In addition, the application of bioerosion patterns regionally and through time is a recent valuable worthy palaeoenvironmental tool not as yet developed for Patagonia. We attempted to characterize, qualitatively/semiquantitatively, the ichnotaxonomic composition of the coastal area of northern Golfo San Jorge since the Late Pleistocene; to compare results with those obtained for other geographical areas along Patagonia and the Bonaerensian coastal sectors; lastly, to evaluate its palaeoenvironmental/palaeoclimatic significance in a clue area in terms of circulation patterns near the Southern Ocean climatic pump. At Bustamante (Northern Patagonia Frontal System) Domichnia traces were dominant during the Late Pleistocene while Praedichnia in the mid-Holocene. Bustamante exhibits the highest ichnodiversity for the whole Argentinean coastal area. Ichnodiversity is not strongly different between Late Pleistocene and mid-Holocene interglacials and compared to present; however, the relative abundance of some ichnotaxa (e.g., Oichnus, Iramena, Pennatichnus, at Camarones; Oichnus
Un suelo referible al periodo calido medieval en Patagonia Austral y Tierra del Fuego (Argentina. Aspectos cronologicos y paleoclimaticos

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Favier Dubois, C. M.

2002-08-01

Full Text Available Geoarchaeological work done in Southernmost Patagonia and in the north of Tierra del Fuego, have revealed the recurrent presence of a paedogenesis interval represented by a soil of an A-AC-C profile, with a mollic epipedon, in the upper section of eolian and colluvial deposits of the late Holocene. This soil is today buried in the sites that have been analyzed, while it remains exposed in other areas of the landscape. Radiocarbon dates obtained on materials placed below it (maximum ages and those obtained by OCR (Oxidizable Carbon Ratio in the AC horizon of this soil (minimum ages, indicate the beginning of its development around the year 1000 BP. Its chronology and environmental implications suggest a relationship with the medieval climatic fluctuations called Medieval Warm Period or Medieval Optimum in Europe. This period has correlates detected in Patagonia by dendroclimatic studies.Estudios geoarqueológicos realizados en 5 localidades de Patagonia austral y norte Tierra del Fuego han revelado la recurrente presencia de un suelo de perfil A-AC-C, de epipedon mólico, en depósitos eólicos y coluviales del Holoceno tardío. Este suelo se observa sepultado en los yacimientos arqueológicos analizados, mientras que permanece expuesto en otras posiciones del paisaje. Numerosas edades máximas y mínimas obtenidas por 14C y por la técnica de OCR (Oxidizable Carbon Ratio indican el comienzo de su desarrollo hacia el 1000 AP. Su cronología e implicancias ambientales permiten vincularlo con fluctuaciones climáticas desarrolladas durante el denominado Período Cálido Medieval u Optimo Medieval Europeo, con correlatos detectados en Patagonia a través de estudios dendroclimáticos.
Variability of Soil Types in Wetland Meadows in the South of the Chilean Patagonia Variabilidad de Tipos de Suelos en Las Vegas del Sur de la Patagonia Chilena

OpenAIRE

Ladislava Filipová; Radim Hédl; Nilo Covacevich C.

2010-01-01

The wetland meadows and pastures (vegas) of the agricultural zone of the Magallanes Region and the Chilean Patagonia are productive and intensively exploited ecosystems. However, there is scarce data about the typology and the physical and chemical properties of the soils that determine the agricultural potential of vegas sites. Sampling of the main horizons of 47 soil profiles was conducted throughout the area. The profiles were described in the field and consequently classified according to...
Ground level and Lidar monitoring of volcanic dust and dust from Patagonia

Science.gov (United States)

Otero, L. A.; Losno, R.; Salvador, J. O.; Journet, E.; Qu, Z.; Triquet, S.; Monna, F.; Balkanski, Y.; Bulnes, D.; Ristori, P. R.; Quel, E. J.

2013-05-01

A combined approach including ground level aerosol sampling, lidar and sunphotometer measurements is used to monitor suspended particles in the atmosphere at several sites in Patagonia. Motivated by the Puyehue volcanic eruption in June 2011 two aerosol monitoring stations with several passive and active instruments were installed in Bariloche and Comodoro Rivadavia. The main goal which is to monitor ground lifted and transported ashes and dust involving danger to civil aviation, is achieved by measuring continuously aerosol concentration at ground level and aerosol vertical distribution using lidar. In addition, starting from December 2011, continuous series of weekly accumulated aerosol concentrations at Rio Gallegos are being measured to study the impact of Patagonian dust over the open ocean on phytoplankton primary productivity and CO2 removal. These measurements are going to be coupled with LIDAR monitoring and a dust optical response models to test if aerosol extrapolation can be done from the ground to the top of the layer. Laboratory chemical analysis of the aerosols will include elemental composition, solubilisation kinetic and mineralogical determination. Expected deliverables for this study is the estimation of the amount of dust exported from Patagonia towards the South Atlantic, its chemical properties, including bioavailability simulation, from model and comparison to experimental measurements.
Mandibular second premolar with three canals: Re-treatment of a case with unusual root canal anatomy

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Niranjan Desai

2011-01-01

Full Text Available A thorough knowledge of root canal anatomy along with the anatomical variations that may be present is essential for success of endodontic therapy. Unusual presentations in the number of the roots or the canals should be expected in every tooth. Mandibular second premolars are thought of as having a single root and canal. Studies have stated that the prevalence of three canals with three orifices in this tooth is 0.4%. The mandibular second premolar is particularly difficult to treat owing to the fact that a wide variation in the number, location and curvature of the roots and canals exist. Added to this is the fact that the access opening is restricted and location of the lingually placed orifices is difficult. This case report details the re-treatment of a mandibular second premolar with three canals and three separate orifices using the surgical microscope.
The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

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Soledad Molares

2012-01-01

Full Text Available Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60% in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species, mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts.
The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

Science.gov (United States)

Molares, Soledad; Ladio, Ana

2012-01-01

Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60%) in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species), mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts. PMID:22194774
Estado actual del conocimiento de la familia Ceratopogonidae en la Patagonia (Diptera: Nematocera

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Gustavo R. SPINELLI

2009-01-01

Full Text Available Ceratopogonidae incluye pequeños dípteros nematocerosque crían en hábitats acuáticos o semiacuáticos. Hasta los ‘80, el conocimiento de su taxonomía en la Patagonia se hallaba limitado a la contribución de los comienzos de los ‘30 de Ingram y Macfie, sobre la base de material capturado en 1926-27, en el área del Parque Nacional Nahuel Huapi y zonas vecinasde Chile. En los últimos 25 años, se pusieron en marcha diferentes proyectos, resultando la descripción o registro de numerosos taxones para la región. Si se contabilizan los datos publicados, 102 especies habitan en la Patagonia, de las cuales 86 (84,31% son endémicas para la región. Este alto porcentaje es evidente en los bosques de Nothofagus, con 71 especies endémicas de estebioma, nueve lo son de la estepa y seis presentan registros en bosque y estepa. Datos aún no publicados concuerdan con este esquema. Diecinueve géneros están representados en la Patagonia, diez de ellos con amplia distribución,tres de distribución transantártica y seis son endémicos para el área. Para la misma, se hallan publicadas las revisiones de Forcipomyia, Atrichopogon, Borkenthelea, Macrurohelea y Paradasyhelea; se han finalizado y aún no publicado aquellas de Dasyhelea y Palpomyia, está muy avanzada la de Stilobezzia y se prevé comenzar con las de Austrohelea, Austrosphaeromias, Physohelea y Bezzia. Se calcula que estos datos no divulgados contienen al menos 55 especies todavía no descriptas. Con respecto a los aspectos biogeográficos se pueden destacar estudios que tienden a establecer relaciones entre las áreas reconocidas en esquemas biogeográficos propuestos para la región andina.
The enlargement of geniculate fossa of facial nerve canal: a new CT finding of facial nerve canal fracture

International Nuclear Information System (INIS)

Gong Ruozhen; Li Yuhua; Gong Wuxian; Wu Lebin

2006-01-01

Objective: To discuss the value of enlargement of geniculate fossa of facial nerve canal in the diagnosis of facial nerve canal fracture. Methods: Thirty patients with facial nerve canal fracture underwent axial and coronal CT scan. The correlation between the fracture and the enlargement of geniculate fossa of facial nerve canal was analyzed. The ability of showing the fracture and enlargement of geniculate fossa of facial nerve canal in axial and coronal imaging were compared. Results: Fracture of geniculate fossa of facial nerve canal was found in the operation in 30 patients, while the fracture was detected in CT in 18 patients. Enlargement of geniculate ganglion of facial nerve was detected in 30 patients in the operation, while the enlargement of fossa was found in CT in 28 cases. Enlargement and fracture of geniculate fossa of facial nerve canal were both detected in CT images in 18 patients. Only the enlargement of geniculate fossa of facial nerve canal was shown in 12 patients in CT. Conclusion: Enlargement of geniculate fossa of facial nerve canal was a useful finding in the diagnosis of fracture of geniculate fossa in patients with facial paralysis, even no fracture line was shown on CT images. (authors)
Industrial canal waterfronts in The Netherlands : transforming the canal zones of B5

NARCIS (Netherlands)

Curulli, G.I.

2012-01-01

Industrial Canal Waterfronts in The Netherlands provides a comprehensive presentation of the characteristics and challenges of five interconnected and dismissed industrial canal zones located in the Dutch Brabant cities of Eindhoven, Breda, Tilburg, s’-Hertogenbosch and Helmond (B5). Through the
Pasado y presente del uso de plantas silvestres con órganos subterráneos de almacenamiento comestibles en la Patagonia

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Juan J. Ochoa

2011-07-01

Full Text Available El presente trabajo es la primara aproximación acerca del papel de las plantas con órganos de almacenamiento subterráneos comestibles (POAS en la Patagonia, desde una perspectiva temporal y espacial, al integrar datos etnohistóricos y etnográficos actuales ligados al uso de las POAS. El 75 % de las 54 fuentes analizadas mencionan el uso de POAS en la alimentación humana de la Patagonia. Las POAS silvestres comestibles registradas ascienden a 51 especies, siendo mayor el conjunto de POAS con raíces comestibles. La estepa y zonas ecotonales resultaron las de mayor riqueza de POAS, probablemente vinculado a adaptaciones ecológicas de éstas a la aridez en el primer caso, como a la alta diversidad relativa que presentan los ecotonos, en el segundo. El registro etnohistórico mostró discontinuidades marcadas, siendo pocas las especies presentes por más de un siglo, destacándose la continuidad documental de A. tuberosa desde el siglo XVIII al presente, así como la incorporación reciente de especies exóticas. Las fuentes etnohistóricas revisadas y su contraste con datos etnobotánicos recientes de campo sugieren dinamismo en los patrones de utilización, que a lo largo del tiempo han llevado al abandono del uso de las POAS en la práctica alimentaria de la Patagonia. Las singularidades encontradas respecto a lo temporal y espacial pueden vincularse tanto a los conocimientos locales y específicos desarrollados a lo largo del tiempo por los habitantes de la Patagonia, como también a las circunstancias sociopolíticas y académicas de cada una de las fuentes analizadas.
Diagnosis and root canal treatment in a mandibular premolar with three canals.

Science.gov (United States)

Soares, Lanuce Rosa; Arruda, Marcos; de Arruda, Marcos Pôrto; Rangel, Andréa Leão; Takano, Edson; de Carvalho Júnior, Jacy Ribeiro; Saquy, Paulo Cesar

2009-01-01

This paper presents a case report of a left mandibular second premolar with three canals and three different apical foramina. A 39-year-old male patient presented to our clinic with pain in the mandibular left second premolar. Initially, pain was caused by cold stimulus and later was spontaneously. The intraoral clinical examination revealed a fractured amalgam restoration with occlusal caries. Percussion and cold (Endo-Frost) tests were positive. The radiographic examination showed the presence of two roots. The probable diagnosis was an acute pulpitis. After access cavity, it was observed remaining roof of the pulp chamber and mild bleeding in the tooth lingual area, indicating the possible presence of a third canal. The endodontic treatment was completed in a single session using Root ZX apex locator and K3 NiTi rotary system with surgical diameter corresponding to a .02/45 file in the three canals and irrigation with 1% sodium hypochlorite. The canals were obtured with gutta-percha cones and Sealer 26 using the lateral condensation technique. After 1 year of follow-up, the tooth was asymptomatic and periapical repair was observed radiographically. Internal alterations should be considered during the endodontic treatment of mandibular second premolars. The correct diagnosis of these alterations by the analysis of preoperative radiographs can help the location of two or more canals, thereby avoiding root therapy failure.
Hydroclimatic conditions trigger record harmful algal bloom in western Patagonia (summer 2016)

OpenAIRE

León-Muñoz, Jorge; Urbina, Mauricio A.; Garreaud, René; Iriarte, José Luis

2018-01-01

A harmful algal bloom (HAB) of the raphidophyta alga Pseudochattonella cf. verruculosa during the 2016 austral summer (February-March) killed nearly 12% of the Chilean salmon production, causing the worst mass mortality of fish and shellfish ever recorded in the coastal waters of western Patagonia. The HAB coincided with a strong El Niño event and the positive phase of the Southern Annular Mode that altered the atmospheric circulation in southern South America and the adjacent Pacific Ocean. ...
Hydrocele of the canal of Nuck

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Nourah ALSaleh

2018-02-01

Full Text Available Hydrocele of the canal of Nuck is a rare condition in female children caused by a failure of complete obliteration of the canal of Nuck. The canal of Nuck is an abnormal patent pouch of the peritoneum extending anterior to the round ligament of the uterus into the labia majora. Incomplete obliteration of this canal (patent processus vaginalis can result in either an inguinal hernia or a hydrocele. Here, we report two cases of hydrocele of the canal of Nuck presented within a two-month period. In the first case, incarcerated right-sided inguinal hernia was suspected while the second case was clinically diagnosed as encysted hydrocele of canal of Nuck. Both patients underwent surgical exploration. Hydrocelectomy with high ligation was also performed. One month after the surgery, the first patient showed signs of hydrocele on contralateral side, while the other patient showed no sign of contralateral hydrocele or hernia.
Assessment of three root canal preparation techniques on root canal geometry using micro-computed tomography: In vitro study

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Shaikha M Al-Ali

2012-01-01

Full Text Available Aim: To assess the effects of three root canal preparation techniques on canal volume and surface area using three-dimensionally reconstructed root canals in extracted human maxillary molars. Materials and Methods: Thirty extracted Human Maxillary Molars having three separate roots and similar root shape were randomly selected from a pool of extracted teeth for this study and stored in normal saline solution until used. A computed tomography scanner (Philips Brilliance CT 64-slice was used to analyze root canals in extracted maxillary molars. Specimens were scanned before and after canals were prepared using stainless steel K-Files, Ni-Ti rotary ProTaper and rotary SafeSiders instruments. Differences in dentin volume removed, the surface area, the proportion of unchanged area and canal transportation were calculated using specially developed software. Results: Instrumentation of canals increased volume and surface area. Statistical analysis found a statistically significant difference among the 3 groups in total change in volume (P = 0.001 and total change in surface area (P = 0.13. Significant differences were found when testing both groups with group III (SafeSiders. Significant differences in change of volume were noted when grouping was made with respect to canal type (in MB and DB (P < 0.05. Conclusion: The current study used computed tomography, an innovative and non destructive technique, to illustrate changes in canal geometry. Overall, there were few statistically significant differences between the three instrumentation techniques used. SafeSiders stainless steel 40/0.02 instruments exhibit a greater cutting efficiency on dentin than K-Files and ProTaper. CT is a new and valuable tool to study root canal geometry and changes after preparation in great details. Further studies with 3D-techniques are required to fully understand the biomechanical aspects of root canal preparation.
21 CFR 872.3810 - Root canal post.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal post. 872.3810 Section 872.3810 Food... DEVICES DENTAL DEVICES Prosthetic Devices § 872.3810 Root canal post. (a) Identification. A root canal... of the platinum group intended to be cemented into the root canal of a tooth to stabilize and support...

Mineralogical association in the zone of argillic advanced alteration in a kaolin deposit of Patagonia Argentina

International Nuclear Information System (INIS)

Rainoldi, A; Oviedo, P.; Maiza, P.; Marfil, S.

2010-01-01

This work is about the mineralogical and petrological relations of the para genetic association of advanced argillic zone in the kaolin deposit in Patagonia.This study allowed to establish the sequence of events that took place in the deposit as well as the conditions under which they were generated
First paleoparasitological study of micromammal coprolites from the holocene of the Somuncurá Plateau Protected Natural Area (Patagonia Argentina).

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Beltrame, María Ornela; Bellusci, Agustín; Andrade, Analía

2018-02-27

The Somuncurá Plateau is a Protected Natural Area located in the middle of the northern extra-Andean arid Patagonia. Inhabited by at least 20 small mammal species, is the place with the uppermost species richness in Patagonia. The aim of this study was to examine the parasite remains from micromammal coprolites collected in association with a bone sequence recovered at the east of the Somuncurá Plateau (site "Alero Las Lechuzas"). Coprolites came from the four temporal units previously defined: unit I (4790 ± 100 yrs. 14 C B.P.), unit II, unit III (7840 ± 120 yrs. 14 C B.P.) and unit IV. Each coprolite was processed, rehydrated, homogenized, processed by spontaneous sedimentation and examined using a light microscope. Coprolites and eggs were described, measured and photographed. Samples were positive for two nematode species: Helminthoxys caudatus Freitas, Lent & Almeida, 1937 (Oxyurida, Oxyuridae) and Trichuris spp. (Trichinellida: Trichuridae). This is the first paleoparasitological study developed for the Somuncurá Plateau Protected Area. Moreover, this is the first time that the genus Helminthoxys is reported from ancient times worldwide. Coprolites were attributed to the mountain cavy Microcavia australis (Rodentia, Caviidae).The presence of H. caudatus for the Middle Holocene of northern Patagonia contributes to the study of the history of the histricomorphs and pinworms relationships. Copyright © 2018 Elsevier B.V. All rights reserved.
Semiconductor laser irradiation improves root canal sealing during routine root canal therapy

Science.gov (United States)

Hu, Xingxue; Wang, Dashan; Cui, Ting; Yao, Ruyong

2017-01-01

Objective To evaluate the effect of semiconductor laser irradiation on root canal sealing after routine root canal therapy (RCT). Methods Sixty freshly extracted single-rooted human teeth were randomly divided into six groups (n = 10). The anatomic crowns were sectioned at the cementoenamel junction and the remaining roots were prepared endodontically with conventional RCT methods. Groups A and B were irradiated with semiconductor laser at 1W for 20 seconds; Groups C and D were ultrasonically rinsed for 60 seconds as positive control groups; Groups E and F without treatment of root canal prior to RCT as negative control groups. Root canal sealing of Groups A, C and E were evaluated by measurements of apical microleakage. The teeth from Groups B, D and F were sectioned, and the micro-structures were examined with scanning electron microscopy (SEM). One way ANOVA and LSD-t test were used for statistical analysis (α = .05). Results The apical sealing of both the laser irradiated group and the ultrasonic irrigated group were significantly different from the control group (pirrigated group (p>0.5). SEM observation showed that most of the dentinal tubules in the laser irradiation group melted, narrowed or closed, while most of the dentinal tubules in the ultrasonic irrigation group were filled with tooth paste. Conclusion The application of semiconductor laser prior to root canal obturation increases the apical sealing of the roots treated. PMID:28957407
The shape of the human lumbar vertebral canal A forma do canal vertebral lombar humano

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Edmundo Zarzur

1996-09-01

Full Text Available Literature on the anatomy of the human vertebral column characterizes the shape of the lumbar vertebral canal as triangular. The purpose of the present study was to determine the precise shape of the lumbar vertebral canal. Ten lumbar vertebral columns of adult male cadavers were dissected. Two transverse sections were performed in the third lumbar vertebra. One section was performed at the level of the lower border of the ligamenta flava, and the other section was performed at the level of the pedicles. The shape of the lumbar vertebral canal at the level of the pedicles tends to be oval or circular, whereas the shape of the lumbar vertebral canal at the level of the lower border of the ligamenta flava is triangular. Thus, the shape of the human lumbar vertebral canal is not exclusively triangular, as reported in the literature. It is related to the level of the transversal section performed on the lumbar vertebra. This finding should be taken into consideration among factors involved in the spread of solutions introduced into the epidural space.A literatura sobre a anatomia da coluna vertebral descreve como sendo triangular o formato do canal vertebral na região lombar. O objetivo deste estudo é determinar a real forma do canal da coluna vertebral lombar.Dez colunas vertebrais de cadáveres de homens adultos foram dissecadas. Dois cortes transversais foram executados na terceira vértebra lombar. Um corte foi feito no nível das bordas inferiores de dois ligamentos amarelos vizinhos e o outro corte foi transversal, no nível dos pedículos. A forma do canal vertebral variou: no nível dos pedículos ela tende a ser oval ou circular e junto às bordas inferiores dos ligamentos amarelos passa a ser triangular. Portanto, a forma do canal vertebral lombar não é somente triangular; ela depende do nível em que se faz o corte transversal da vértebra. Estes achados devem ser levados em consideração entre os fatores envolvidos na difusão das
Mio-Pliocene glaciations of Central Patagonia: New evidence and tectonic implications Glaciaciones mio-pliocenas en Patagonia central: nueva evidencia e implicancias tectónicas

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Yves Lagabrielle

2010-07-01

Full Text Available Patagonia is well known for spectacular oceurrences of a variety of glacial-derived landforms and deposits and for a long history of ancient glaciations. In this paper, we first review the diverse evidence that demonstrates the development of glacial-related sedimentary units within the Central Patagonian Cordillera since 7 Ma. Well preserved glacial landforms at the top surface of mesetas on both sides of the Lago General Carrera-Buenos Aires are described: the Meseta Guenguel to the north, and the volcanic Meseta del Lago Buenos Aires to the south. The latter meseta corresponds to a 3 Ma old, morphologically inverted paleo-piedmont, based on Ar/Ar dates of the uppermost lava flows. It shows evidence of glacier advances to the NE direction. Over a distance of 20 km, glacial landforms observed by remote sensing data and digital elevation model define glacial tongues that were fed by the Cordillera reliefs to the west. These lobes are now beheaded from their westward sources along a morpho-structural corridor that bounds the Meseta del Lago Buenos Aires to the west. These remnants can be correlated with the oldest glacial landforms recognized north of Lago General Carrera-Buenos Aires, on the Meseta Guenguel that form the Chipanque moraine system. From these features it is concluded that the glacial drainage network of Central Patagonia has been strongly modified following relief inversion in response to erosion processes and to tectonic causes. Changes occurred after 3 Ma, from a smooth piedmont surface covered by an extensive ice mantle ending with ampie glacial lobes, to the current series of deeply incised glacial valleys such as the Lago General Carrera-Buenos Aires depression. These new data bear important con-straints on the history and development of the first glaciations in southern South America.Patagonia es bien conocida por una espectacular geomorfología glacial y por una larga historia de antiguas glaciaciones. En este art
Investigación sobre manejo forestal a largo plazo en Patagonia Sur -Argentina: Lecciones del pasado, desafíos del presente Long-term forest management research in South Patagonia - Argentina: Lessons from the past, challenges from the present

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GUILLERMO J MARTÍNEZ-PASTUR

2010-03-01

Full Text Available Argentina ha basado su economía en la agricultura y el ganado, donde el bosque ha sido visto como un obstáculo para el desarrollo. La cosecha forestal en Patagonia Sur ha sido una actividad basada en la colonización y explotación de nuevas áreas. Esta se realiza principalmente en bosques primarios sin ningún manejo silvícola posterior. A pesar de que el manejo actual no es sustentable, la investigación científica ha definido las bases para conservar, proteger y mejorar las propuestas de manejo forestal para los bosques nativos de Patagonia Sur. Las primeras parcelas de estudio a largo plazo (1965-1966 basaron su monitoreo en parámetros económicos y estructura forestal, estableciéndose cerca de veinte parcelas en bosques fiscales de Tierra del Fuego. La mayoría fueron destruidas o discontinuadas debido a la falta de planificación del uso de la tierra, escaso interés social en la investigación, falta de compromiso de instituciones, y poca colaboración con empresas forestales. Posteriormente, un segundo grupo de nueve parcelas se estableció en Patagonia Sur (1993-2004 basado en la colaboración entre empresas privadas e instituciones nacionales. Los objetivos incluyeron parámetros económicos y ecológicos. Las parcelas se establecieron en tierras privadas conjuntamente con empresas privadas y estancieros, mediante la firma de acuerdos y proyectos de investigación. Los principales problemas encontrados fueron: falta de compromiso de las administraciones forestales, ausencia de proyectos financiados a largo plazo, y que la responsabilidad de las parcelas continúa bajo la iniciativa personal de los investigadores participantes. El estudio de las parcelas permitió: (i proponer nuevos sistemas de regeneración basados en la maximización del rendimiento y el mejoramiento del valor de conservación de los bosques manejados (e.g., retención variable y sistemas silvopastoriles, (ii determinar la factibilidad económica de aplicaci
Inter-subjectivity and Domestication in the Making of a Global Region: Territorialization of Salmon in the Chilean Patagonia.

NARCIS (Netherlands)

Blanco, Gustavo; Arce, A.M.G.; Fisher, E.F.

2016-01-01

This article examines transformations in the Chilean Patagonia, a region that has become a world leader in Salmon production for global markets. Employing ethnographic methods, this study examines the possibilities of considering inter-subjectivities in the processes of conforming important regions
Dorello's Canal for Laymen: A Lego-Like Presentation.

Science.gov (United States)

Ezer, Haim; Banerjee, Anirban Deep; Thakur, Jai Deep; Nanda, Anil

2012-06-01

Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students.
Glaciers in Patagonia: Controversy and prospects

Science.gov (United States)

Kargel, J. S.; Alho, P.; Buytaert, W.; Célleri, R.; Cogley, J. G.; Dussaillant, A.; Guido, Z.; Haeberli, W.; Harrison, S.; Leonard, G.; Maxwell, A.; Meier, C.; Poveda, G.; Reid, B.; Reynolds, J.; Rodríguez, C. A. Portocarrero; Romero, H.; Schneider, J.

2012-05-01

Lately, glaciers have been subjects of unceasing controversy. Current debate about planned hydroelectric facilities—a US7- to 10-billion megaproject—in a pristine glacierized area of Patagonia, Chile [Romero Toledo et al., 2009; Vince, 2010], has raised anew the matter of how glaciologists and global change experts can contribute their knowledge to civic debates on important issues. There has been greater respect for science in this controversy than in some previous debates over projects that pertain to glaciers, although valid economic motivations again could trump science and drive a solution to the energy supply problem before the associated safety and environmental problems are understood. The connection between glaciers and climate change—both anthropogenic and natural—is fundamental to glaciology and to glaciers' practical importance for water and hydropower resources, agriculture, tourism, mining, natural hazards, ecosystem conservation, and sea level [Buytaert et al., 2010; Glasser et al., 2011]. The conflict between conservation and development can be sharper in glacierized regions than almost anywhere else. Glaciers occur in spectacular natural landscapes, but they also supply prodigious exploitable meltwater.
Microbiological examination of infected dental root canals.

Science.gov (United States)

Gomes, B P F A; Pinheiro, E T; Gadê-Neto, C R; Sousa, E L R; Ferraz, C C R; Zaia, A A; Teixeira, F B; Souza-Filho, F J

2004-04-01

The aim of this study was to investigate the root canal microbiota of primary and secondary root-infected canals and the association of constituent species with specific endodontic signs and symptoms. Microbial samples were taken from 60 root canals, 41 with necrotic pulp tissues (primary infection) and 19 with failed endodontic treatment (secondary infection). Strict anaerobic techniques were used for serial dilution, plating, incubation and identification. A total of 224 cultivable isolates were recovered belonging to 56 different bacterial species. Individual root canals yielded a maximum of 10 bacterial species. Of the bacterial isolates, 70% were either strict anaerobes or microphilic. The anaerobes most frequently isolated were: Peptostreptococcus micros (35%), Fusobacterium necrophorum (23.3%), Fusobacterium nucleatum (11.7%), Prevotella intermedia/nigrescens (16.7%), Porphyromonas gingivalis (6.7%) and Porphyromonas endodontalis (5%). The root canal microflora of untreated teeth with apical periodontitis was found to be mixed, comprising gram-negative and gram-positive and mostly anaerobic microorganisms and usually containing more than 3 species per canal. On the other hand, facultative anaerobic and gram-positive bacteria predominated in canals with failed endodontic treatment, which harbored 1-2 species per canal. Suggested relationships were found between anaerobes, especially gram-negatives, and the presence or history of pain, tenderness to percussion and swelling (PEubacterium spp. (both Pspp. (Pspp. (Pspp. (Pspp. (Pspp. (Pspp. (Pspp. (Pspp., P. micros, F. necrophorum (P<0.05). Our findings indicate potential complex interactions of species resulting in characteristic clinical pictures which cannot be achieved by individual species alone. They also indicate that the microbiota of primary infected canals with apical periodontitis differs in number and in species from the secondary infected canals by using the culture technique.
External dose conversion factor from canal water

International Nuclear Information System (INIS)

Bhargava, Pradeep; Chitra, S.; Mhatre, Arti S.; Singh, Kapil Deo

2016-01-01

External dose needs to be estimated for the radioactivity discharged into the canal, as it constitutes one of the pathways of exposure to the public. Two activities are considered here: i) a walk along the bank of the canal ii) and the walk on the bridge. A concentration of 1 Bq/l is assumed here for the gross beta activity for the estimation of the dose conversion factor. A canal of width 14.39 m and the depth of 2.5 m is considered for this study. Length of the canal is taken to be infinite. Canal side wall is assumed to be the 25 cm thick concrete. Two points are selected, one on the bank, and the second on a bridge 1 m above the top surface of canal water. Dose Conversion factors for the person moving on the Bridge (at one meter above the water surface) and standing on bank of canal is estimated by using the QAD CG code for 137 Cs. Dose conversion factors for the location mentioned above are found to be 1.11E-10 Sv/hr/(Bq/l) and 1.55 E-11 Sv/hr/(Bq/l) for bridge and bank of canal respectively. (author)
Clinical significance of dental root canal microflora.

Science.gov (United States)

Gomes, B P; Lilley, J D; Drucker, D B

1996-01-01

Previous work by this group has shown that a significant association exists between pain and the presence of either Prevotella or Peptostreptococcus spp. in dental root canals. The aim of this study was to examine a more extensive series of canals microbiologically, to determine whether any other particular endodontic symptoms or clinical signs showed specific associations with individual bacterial species. Seventy root canals were examined microbiologically and clinical data collected to investigate in detail such associations. Of the canals studied, 37 were associated with pain, 49 with tenderness to percussion, 23 with swelling, six with purulent exudate and 57 presented with wet root canals. Anaerobes were isolated from 70.3% of painful canals and from 29.7% of pain-free canals. Significant associations were found between (a) pain and either Prevotella spp. or peptostreptococci, both with P spp. (P Eubacterium spp. (P spp. or Pstr. micros, both with P spp. (each P Eubacterium, Peptostreptococcus, Prevotella or Propionibacterium (each P < 0.05). It was concluded that several different endodontic clinical signs and symptoms are significantly associated with specific bacterial species.
El Canal del Atazar I

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López de Berges y de los Santos, Emilio

1967-03-01

Full Text Available The Atazar Canal helps to supply Madrid with water, from the rivers Lozoya, Jarama and Sorbe. The section which operates at present starts at the Torrelaguna dam and finishes at the El Goloso reservoir. Later a further section will be added, from the Atazar dam, on the Lozoya river, to link up with the control dam at Torrelaguna. The canal capacity is 16 m3/sec, and it is 43.47 km long. It has a slope of 4/10.000. The cross section is similar to that of the Jarama canal, already built. There are interconnections between this canal and the Canal Alto, which previously supplied the high and medium part of Madrid. To overcome the ground unevenness 5 syphons have been built, the most important of which is the Colmenar Goloso syphon, which is 10.88 km in length. Construction commenced on December 10, 1962, and water reached Madrid on June 15th, 1966. The initial budget for this project was 1,500 million pesetas.El canal del Atazar refuerza considerablemente el abastecimiento de aguas a Madrid, procedentes de los ríos Lozoya, Jarama y, en un próximo futuro, del Sorbe. El tramo, actualmente en funcionamiento, empieza en el salto de Torrelaguna y finaliza en los depósitos de El Goloso. Más adelante se completará su trazado mediante un nuevo tramo que partirá del embalse de Atazar, en el Lozoya, para unirse al actual en el depósito regulador de Torrelaguna. Su capacidad es de 16 m3/s; su longitud, 43,471 km, y su pendiente, 4 diezmilésimas. La sección tipo es análoga a la del canal del Jarama, de construcción anterior. Mediante la oportuna obra de transvase se realizan intercambios entre este Canal y el Canal Alto que abastecía anteriormente la parte media y alta de la capital. Para salvar los desniveles del terreno se han construido 5 sifones, siendo el más importante el de Colmenar-Goloso, con una longitud de 10,8S4 km. El comienzo de las obras tuvo lugar el 10 de diciembre de 1962, y el agua llegó a Madrid el 15 de junio de 1966. Su
Detection of Mesiobuccal Canal in Maxillary Molars and Distolingual Canal in Mandibular Molars by Dental CT: A Retrospective Study of 100 Cases

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Sushma Rathi

2010-01-01

Full Text Available Objective. To detect presence of MB2 canal in maxillary molars and distolingual canal in mandibular molars by Dental CT. Material and Methods. A retrospective study of 100 Dental CTs was done. Axial and paraxial images obtained were used to assess the presence of MB2 canal in maxillary molars and distolingual canal in mandibular molars. Results. The youngest patient was of 11 years while the eldest patient was of 77 years. Males were 58 in number and females were 42 in number. MB2 canals were present in 57 patients and distolingual canal was present in 18 patients. Maximum MB2 canals were present in age group between 51 and 60 years, while distolingual canals were present in age group of 21–30 years. Conclusion. Dental CT allows adequate visualization of variation in root canal morphology and can be important diagnostic tool for successful endodontic therapy.
Caracterización de un proceso de biorremediación de hidrocarburos en deficiencia de nitrógeno en un suelo de la Patagonia Argentina

OpenAIRE

Acuña, Adrián Javier; Pucci Ceima, Oscar Héctor; Pucci Bissetta, Graciela Natalia

2008-01-01

La zona central de la Patagonia, Argentina, se encuentra sometida a explotación petrolera y sus suelos se caracterizan por ser deficientes en nitrógeno. Esto causaría un efecto negativo en los procesos de atenuación natural que se desarrollan en los suelos contaminados con hidrocarburos. El objeto de este estudio fue determinar cual es el efecto de la deficiencia de nitrógeno sobre la biodegradación de los hidrocarburos en un suelo de la Patagonia, Argentina. Se trabajó con tres micr...
77 FR 42644 - Safety Zone; Canal Fest of the Tonawandas, Erie Canal, Tonawanda, NY

Science.gov (United States)

2012-07-20

.... ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the... Canal during the Canal Fest of the Tonawandas Fireworks display. This temporary safety zone is necessary to protect spectators and vessels from the hazards associated with a fireworks display. DATES: This...
Water Environment Evolution along the China Grand Canal

International Nuclear Information System (INIS)

Mao, F; Wu, Y X; Yang, B F; Li, X J

2014-01-01

The China Grand Canal is one of the earliest canals in the world, having lasted for nearly 3000 years. Even its section canals have a rich history, such as the North-South Grand Canal that was established during the Sui Dynasty, whereas the Beijing-Hangzhou Canal was excavated during the Yuan Dynasty and the east line of the South-to-North Water Diversion. As one of the longest in the world, the China Grand Canal's total length is over 3500 kilometers. This length includes the navigable, unnavigable, and underground sections. Making the best use of situations and according to local conditions, the Chinese people harmoniously constructed the Beijing-Hangzhou Canal with nature. Tens of millions of workers took nearly 3000 years to complete the great shipping system. Navigable sections still exist for up to 900 kilometers and the volume of freight traffic is approximately 300 million tons. The canal remains the main logistical channel of the North-to-South Coal Transportation, South-to-North Water Diversion, and resources circulation. To date, China is promoting the success of heritage application. Part of these efforts is the declaration of the China Grand Canal as a World Cultural Heritage by 2014. In addition, the east route of the South-to-North Water Transfer project is planned to be navigable by 2016. The ancient Beijing-Hangzhou Grand Canal will usher in the new ecological civilization and cultural revival along the canal. This paper presents technical methods of water environment evolution research on the river system, river, and water quality along the Beijing-Hangzhou Canal through the integration of historical literature and modern remote sensing image data. The study carried out water environment investigation and analysis along the Beijing-Hangzhou canal by using ETM, SPOT image data, and GPS measurement data. Spatial and temporal evolution characteristics and regulations of the Beijing-Hangzhou Grand Canal regional water environment in the span of
[Outbreak of histoplasmosis in province of Neuquén, Patagonia Argentina].

Science.gov (United States)

Calanni, Liliana María; Pérez, Rufina Ana; Brasili, Susana; Schmidt, Norma Graciela; Iovannitti, Cristina Adela; Zuiani, María Fernanda; Negroni, Ricardo; Finquelievich, Jorge; Canteros, Cristina Elena

2013-01-01

In Argentina, there are no reports of autochthonous cases of histoplasmosis in the southern regions of the country. To report a histoplasmosis outbreak in Zapala town, Province of Neuquén, Patagonia Argentina. We evaluated the clinical and epidemiological characteristics of 5 patients involved in the outbreak. Environmental studies were conducted to determine the source of infection. The genetic profile of Histoplasma capsulatum strains isolated from the index case (IC) were compared with clinical isolates from Argentinean patients not related to the outbreak, using RAPD-PCR with primers 1281-1283. The patients were residents of Zapala, and had not visited other geographical areas before. All patients had an influenza-like syndrome, and X-ray revealed disseminated micronodular images throughout the lung parenchyma. The IC needed specific antifungal therapy; the remaining 4 patients had mild symptoms, and did not require therapy. All of them had a good clinical outcome. Strains of H. capsulatum isolated from blood culture and lung biopsy of the IC showed a genetic profile different from other strains analyzed. The presence of the fungus in the environment was demonstrated by the detection of anti-Histoplasma antibodies in BALB/c mice inoculated with soil obtained in a culvert where workers had dug up earth after a landslide. This outbreak suggests the histoplasmosis endemic area is under the 38° S parallel. Patients from Neuquén, Patagonia Argentina, with compatible symptoms of histoplasmosis should be tested, regardless of their travel or exposure history. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.
Respiratory function in voluntary participating Patagonia sea lions in sternal recumbency

Directory of Open Access Journals (Sweden)

Andreas Fahlman

2016-11-01

Full Text Available We measured esophageal pressures (n=4, respiratory flow rates (n=5, and expired O2 and CO2 (n=4 in five adult Patagonia sea lions (Otaria flavescens, body mass range 94.3-286.0 kg during voluntary breaths while laying down. The data were used to estimate the dynamic specific lung compliance (sCL, cmH2O-1, the O2 consumption rate (VO2 and CO2 production rates (VCO2 during rest. Our results indicate that the resting tidal volume in Patagonia sea lions is approximately 47-73% of the estimated total lung capacity. The esophageal pressures indicated that expiration is passive during voluntary breaths. The average sCL of dolphins was 0.41±0.11 cmH2O−1, which is similar to those measured in anesthetized sea lions and awake cetaceans, and significantly higher as compared with humans (0.08 cmH2O−1. The average estimated and using breath-by-breath respirometry were 1.023 ± 0.327 L O2 min-1 (range: 0.695-1.514 L O2 min−1 and 0.777 ± 0.318 L CO2 min-1, (range: 0.510-1.235 L CO2 min-1, respectively, which is similar to previously published metabolic measurements from California and Steller sea lions using conventional flow-through respirometry. Our data provide end-tidal gas composition and provide novel data for respiratory physiology in pinnpeds, which may be important for clinical medicine and conservation efforts.
Computed tomography of the facial canal

International Nuclear Information System (INIS)

Kiuchi, Sousuke

1983-01-01

The radiological details of the facial canal was investigated by computed tomography. In the first part of this study, dry skulls were used to delineate the full course of the facial canal by computed tomography. In the second part of this study, the patients with chronic otitis media and secondary cholesteatoma were evaluated. The labyrinthine and tympanic parts of the canal were well demonstrated with the axial scanning, and the mastoid part with the coronal scanning. Moreover, computed tomography showed excellent delineation of the middle ear contents. In patients with secondary cholesteatoma, the destructions of the intratympanic course of the bony facial canal were also assessed preoperatively. (author)

Radiation-induced external ear canal cholesteatoma-like disease

Energy Technology Data Exchange (ETDEWEB)

Ishihara, Akiko; Okuno, Hideji; Noguchi, Keisuke; Komatsuzaki, Atsushi [Tokyo Medical and Dental Univ. (Japan). School of Medicine

1999-06-01

Three cases of cholesteatoma-like disease in the ear canals after radiation therapy for head and neck tumor were reported. Effect of irradiation on bone and soft tissue including skin brings about pathological reaction to the external ear canal as well. Two types of disease resembling cholesteatomas have been recognized: keratosis obturans (KO) and external auditory canal cholesteatoma (EACC). KO appears to be derived from disease of canal skin involved with keratinization, creating a widning of the canal. EACC, on the other hand, seems to develop in the disease of bony canal where a localized absorption of its bone with invasion of squamous epithelium takes place. (author)
Characterization of leveling problems of Patagonia gamma-ray spectrometry survey, Chubut province (Argentina)

International Nuclear Information System (INIS)

Ford, Kenneth L.; Lopez, Luis E.

1998-01-01

Measuring the radioelement concentrations of the soils along traverses perpendicular to the flight line direction was performed in order to gather useful information in support of the leveling of the airborne gamma-ray spectrometer survey of Patagonia. Two sites were selected as test areas which ground and airborne spectrometric data were systematically compared to asses the nature of the leveling problems. It is suspected that variations in soil moisture may play a significant roll in the leveling variations. (author)
Acceleration induced water removal from ear canals.

Science.gov (United States)

Kang, Hosung; Averett, Katelee; Jung, Sunghwan

2017-11-01

Children and adults commonly experience having water trapped in the ear canals after swimming. To remove the water, individuals will shake their head sideways. Since a child's ear canal has a smaller diameter, it requires more acceleration of the head to remove the trapped water. In this study, we theoretically and experimentally investigated the acceleration required to break the surface meniscus of the water in artificial ear canals and hydrophobic-coated glass tubes. In experiments, ear canal models were 3D-printed from a CT-scanned human head. Also, glass tubes were coated with silane to match the hydrophobicity in ear canals. Then, using a linear stage, we measured the acceleration values required to forcefully eject the water from the artificial ear canals and glass tubes. A theoretical model was developed to predict the critical acceleration at a given tube diameter and water volume by using a modified Rayleigh-Taylor instability. Furthermore, this research can shed light on the potential of long-term brain injury and damage by shaking the head to push the water out of the ear canal. This research was supported by National Science Foundation Grant CBET-1604424.
Hood Canal Steelhead - Hood Canal Steelhead Supplementation Experiment

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Hood Canal Steelhead Project is a 17-year before-after-control-impact experiment that tests the effects of supplementation on natural steelhead populations in...
Canal Centring Ability of ProTaper and Mtwo Rotary Systems in Curved Canals

Directory of Open Access Journals (Sweden)

Turkaydin Dilek Erbay

2014-07-01

Full Text Available The purpose of this investigation was to compare centring ratio of ProTaper and Mtwo rotary systems. 60 mandibular molar teeth which had 25, 30 and 35 degree curvature in mesio-buccal root canal were used. Group 1 had 25°, Group 2 had 30°, and Group 3 had 35° curvatures. The roots were sectioned horizontally at 2 mm away from the apex. The apical region was then observed under a stereo-microscope. In each group, teeth were instrumented using ProTaper and Mtwo systems. After canal preparation, digital images of apical part of canals were taken. These images were then superimposed by using Adobe Photoshop CS2 programme. The data were analyzed using ANOVA and Student’s t-test.
Effect of canal preparation with TRUShape and Vortex rotary instruments on three-dimensional geometry of oval root canals.

Science.gov (United States)

Arias, Ana; Paqué, Frank; Shyn, Stephanie; Murphy, Sarah; Peters, Ove A

2018-04-01

The purpose of this study was to assess the geometry of non-round root canals after preparation with TRUShape (a novel instrument with s-shaped longitudinal design) in comparison to conventional rotary instrumentation using micro-computed tomography. Twenty distal root canals of mandibular molars were randomly distributed in two groups to be shaped with either TRUShape or Vortex rotaries. Percentages of unprepared surface and volume of dentin removal for the entire canal and for the apical 4 mm were calculated. Canal transportation and the structure model index (SMI) were assessed. Data were compared with Student t-tests. Shaping with both techniques resulted in similar prepared surface and volume of dentin removed, as well as the extent of canal transportation. The SMI shape factor was significantly lower for TRUShape preparations (P = 0.04) suggesting less rounding during rotary preparation. Although both instruments were suitable for the preparation of oval canals, TRUShape appeared to better conform to the original ribbon-shaped anatomy. © 2017 Australian Society of Endodontology Inc.
Radioanatomy of the singular nerve canal

Energy Technology Data Exchange (ETDEWEB)

Muren, C. [Dept. of Diagnostic Radiology, Sabbatsbergs Hospital, Stockholm (Sweden); Wadin, K. [University Hospital, Uppsala (Sweden); Dimopoulos, P. [University Hospital, Uppsala (Sweden)

1991-08-01

The singular canal conveys vestibular nerve fibers from the ampulla of the posterior semicircular canal to the posteroinferior border of the internal auditory meatus. Radiographic identification of this anatomic structure helps to distinguish it from a fracture. It is also a landmark in certain surgical procedures. Computed tomography (CT) examinations of deep-frozen temporal bone specimens were compared with subsequently prepared plastic casts of these bones, showing good correlation between the anatomy and the images. The singular canal and its variable anatomy were studied in CT examinations of 107 patients. The singular canal could be identified, in both the axial and in the coronal planes. Its point of entry into the internal auditory meatus varied considerably. (orig.)
Nacionalismo territorialista en textos escolares: representaciones de la Patagonia en la dictadura militar argentina (1966-1983 Territorialist nationalism in school textbooks: representations of Patagonia in Argentinian military dictatorship (1966-1983

Directory of Open Access Journals (Sweden)

Jesús Jaramillo

2012-03-01

Full Text Available Los textos escolares desde hace tiempo se han constituido en una de las fuentes primarias para el campo de la Historia de la Educación en tanto son instrumentos de socialización formal básica. Sea considerado registro escrito editorial, herramienta didáctica o registro de memoria escolar, los textos escolares instituyen - y, en ocasiones, eternizan - concepciones e intereses reflejados en sus contenidos "oficiales". Investigaciones recientes en la búsqueda de la realidad escolar han enfatizado la importancia de los mismos en la construcción de las identidades nacionales, pero también de las identidades de grupos socio-culturales, socio-étnicos y regionales. Este artículo, a partir de una indagación historiográfica sobre libros de lectura, intenta reconstruir las diferentes tramas discursivas textuales e iconográficas en que ha sido representada la Patagonia durante los periodos dictatoriales argentinos 1966-1973 y 1976-1983, en escuelas primarias de Río Negro y Neuquén. En principio, puede advertirse un conjunto de relatos de la Patagonia y sus habitantes sobre la base de tres núcleos de sentido: el de territorio indígena, desierto e inculto; el de promisión para el progreso y el turismo; y el de soberanía nacional. A través de sus argumentos daremos cuenta que los libros escolares de edición nacional con rasgos eminentemente políticos pero también étnicos y raciales fueron medios de formación y, sobre todo, dispositivos que coadyuvaron a la conformación de una línea ideológica, política y pedagógica propia del nacionalismo católico militar.School textbooks have long been taken as one of the primary sources for the field of the History of Education, since they are instruments of basic formal socializing. Either as editorial written records, as didactic tools, or as records of school memory, school textbooks institute - and sometimes crystallize - conceptions and interests reflected in their "official" contents
Episodic Jurassic to Lower Cretaceous intraplate compression in Central Patagonia during Gondwana breakup

Science.gov (United States)

Navarrete, César; Gianni, Guido; Echaurren, Andrés; Kingler, Federico Lince; Folguera, Andrés

2016-12-01

From Lower Jurassic to Lower Cretaceous, several intraplate compression events affected discrete sectors of Central Patagonia, under a general context of crustal extension associated with Gondwana breakup. This was demonstrated by means of 2D and 3D seismic and borehole data, which show partial inversion of Lower and Middle Jurassic extensional structures of the Chubut and Cañadón Asfalto basins, during the earliest stages of breakup. A comparison with surrounding areas in Patagonia, where similar Jurassic intraplate compression was described, allowed the discrimination of three discrete pulses of subtle compression (C1: ∼188-185 Ma; C2: ∼170-163; C3: ∼157-136? Ma). Interestingly, episodic intraplate compressional events are closely followed by high flux magmatic events linked to the westward expansion of the Karoo-Ferrar thermal anomaly, which impacted on the lithosphere of southwest Gondwana in Lower Jurassic. In addition, we determined the approximate direction of the main compressive strain (σ1) compatible with other Jurassic intraplate belts of South America. These observations led us to propose a linkage between a thermo mechanically weakened continental crust due to LIPs activity, changes in plate motions and ridge-push forces generated by the opening of the Weddell Sea, in order to explain intraplate shortening, interrupted while Karoo LIPs magmatic invigoration took place.
Evaluation of an indirect elisa for the diagnosis of bovine brucellosis in Patagonia, Argentina

International Nuclear Information System (INIS)

Uzal, F.A.; Carrasco, E.A.; Robles, C.A.; Echaide, S.

1998-01-01

Control and eradication of bovine brucellosis is usually based on the serological detection of antibodies. In Argentina, the Rose Bengal test (RB) and the Buffered Plate antigen test (BPA) are the two screening test officially recognized, while the 2-mercaptoethanol test (2ME) and the Tube Agglutination test (SAT) are the confirmatory assays currently in use. In order to improve the serological diagnosis of bovine brucellosis in Patagonia, Argentina, an indirect ELISA kit produced by the Joint FAO/IAEA Division was evaluated. Sera from negative non-vaccinated, negative but vaccinated and positive animals were tested by all the above techniques. The specificity of the I-ELISA (99.6% and 99.7%) was similar to that of the BPA, RB, 2ME and Complement Fixation test (CF) when used to test sera from non-vaccinated, negative and vaccinated, negative animals, respectively. The sensitivity of the I-ELISA (98%) was higher than the BPA test (96%) and the CF test (95,2%). The I-ELISA kit evaluated in this study was thought to be a valuable tool for the diagnosis of bovine brucellosis in Patagonia region where little epidemiological information is available about this disease and where large numbers of sera should be tested to obtain such information. (author)
Three distal root canals in mandibular first molar with different canal configurations: Report of two cases and literature review

Directory of Open Access Journals (Sweden)

Parul Bansal

2015-01-01

Full Text Available With the increasing number of reports of aberrant root canal morphology, the clinician needs to be aware of the variable anatomy. Various case reports have been published with the finding of middle mesial canal in mandibular first molar, however finding of three distal canals in distal roots of mandibular first molar is rare. This article reports endodontic management of two mandibular first molars presented with three distal canals present in a single distal root (Sert and Bayirli type XVIII and distal and distolingual root.
canal24

Data.gov (United States)

California Natural Resource Agency — Canal system center lines in the Central Valley of California and adjacent areas captured from 1:24,000-scale USGS topographic maps. Updates and modifications made...
The fluid mechanics of root canal irrigation.

Science.gov (United States)

Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

2010-12-01

Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid
The fluid mechanics of root canal irrigation

International Nuclear Information System (INIS)

Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

2010-01-01

Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid
Some History and Hydrology of the Panama Canal

National Research Council Canada - National Science Library

Pabst, Arthur

2000-01-01

At the request of the Panama Canal Commission (now Panama Canal Authority), the Hydrologic Engineering Center participated in the development of a model to simulate the existing operation of the Panama Canal System...
Influence of a glide path on apical extrusion of debris during canal preparation using single-file systems in curved canals.

Science.gov (United States)

Topçuoğlu, H S; Düzgün, S; Akpek, F; Topçuoğlu, G; Aktı, A

2016-06-01

To evaluate the effect of a glide path on the amount of apically extruded debris during canal preparation using single-file systems in curved canals. Ninety extracted mandibular molar teeth were randomly assigned to six groups (n = 15 for each group) for canal instrumentation. Endodontic access cavities were prepared in each tooth. In three of the six groups, a glide path was not created whereas a glide path was created using PathFile instruments on the mesial canals of all teeth in the remaining three groups. The mesial canals of the teeth were then instrumented with the following single-file instrument systems: WaveOne, Reciproc and OneShape. Debris extruded apically during instrumentation was collected into pre-weighed Eppendorf tubes. The tubes were then stored in an incubator at 70 °C for 5 days. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and post-instrumentation weight of the Eppendorf tubes for each group. The data obtained were analysed using one-way analysis of variance (anova) and Tukey's post hoc tests. The OneShape file was associated with less debris extrusion than the Reciproc and WaveOne files when canal instrumentation was performed without a glide path (P files (P > 0.05). There was no significant difference amongst the OneShape, Reciproc and WaveOne files when a glide path was created before canal preparation in curved root canals (P > 0.05). All systems extruded significantly less debris in groups with a glide path than in groups without a glide path (P < 0.05). All instruments were associated with apical extrusion of debris. Creating a glide path prior to canal instrumentation reduced the amount of apically extruded debris in curved canals. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.
Rainforest conifers of Eocene Patagonia: attached cones and foliage of the extant Southeast Asian and Australasian genus Dacrycarpus (Podocarpaceae).

Science.gov (United States)

Wilf, Peter

2012-03-01

Eocene caldera-lake beds at Laguna del Hunco (LH, ca. 52.2 Ma) and Río Pichileufú (RP, ca. 47.7 Ma) in Argentine Patagonia provide copious information about the biological history of Gondwana. Several plant genera from these sites are known as fossils from southern Australia and New Zealand and survive only in Australasian rainforests. The potential presence of Dacrycarpus (Podocarpaceae) holds considerable interest due to its extensive foliage-fossil record in Gondwana, its remarkably broad modern distribution in Southeast Asian and Australasian rainforests, its high physiological moisture requirements, and its bird-dispersed seeds. However, the unique seed cones that firmly diagnose Dacrycarpus were not previously known from the fossil record. I describe and interpret fertile (LH) and vegetative (LH and RP) material of Dacrycarpus and present a nomenclatural revision for fossil Dacrycarpus from South America. Dacrycarpus puertae sp. nov. is the first fossil occurrence of the unusual seed cones that typify living Dacrycarpus, attached to characteristic foliage, and of attached Dacrycarpus pollen cones and foliage. Dacrycarpus puertae is indistinguishable from living D. imbricatus (montane, Burma to Fiji). Dacrycarpus chilensis (Engelhardt) comb. nov. is proposed for Eocene vegetative material from Chile. Modern-aspect Dacrycarpus was present in Eocene Patagonia, demonstrating an astonishingly wide-ranging paleogeographic history and implying a long evolutionary association with bird dispersers. Dacrycarpus puertae provides the first significant Asian link for Eocene Patagonian floras, strengthens the biogeographic connections from Patagonia to Australasia across Antarctica during the warm Eocene, and indicates high-rainfall paleoenvironments.
Canal of Nuck hernia: a multimodality imaging review

Energy Technology Data Exchange (ETDEWEB)

Rees, Mitchell A. [University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States); Squires, James E. [Children' s Hospital of Pittsburgh of UPMC, Department of Gastroenterology, Pittsburgh, PA (United States); Tadros, Sameh; Squires, Judy H. [University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States); Children' s Hospital of Pittsburgh of UPMC, Department of Radiology, Pittsburgh, PA (United States)

2017-07-15

Canal of Nuck abnormalities are a rare but important cause of morbidity in girls, most often those younger than 5 years of age. The canal of Nuck, which is the female equivalent of the male processus vaginalis, is a protrusion of parietal peritoneum that extends through the inguinal canal and terminates in the labia majora. The canal typically obliterates early in life, but in some cases the canal can partially or completely fail to close, potentially resulting in a hydrocele or hernia of pelvic contents. Recognition of this entity is especially important in cases of ovarian hernia due to the risk of incarceration and torsion. We aim to increase awareness of this condition by reviewing the embryology, anatomy and diagnosis of canal of Nuck disorders with imaging findings on US, CT and MRI using several cases from a single institution. (orig.)
Canal of Nuck hernia: a multimodality imaging review

International Nuclear Information System (INIS)

Rees, Mitchell A.; Squires, James E.; Tadros, Sameh; Squires, Judy H.

2017-01-01

Canal of Nuck abnormalities are a rare but important cause of morbidity in girls, most often those younger than 5 years of age. The canal of Nuck, which is the female equivalent of the male processus vaginalis, is a protrusion of parietal peritoneum that extends through the inguinal canal and terminates in the labia majora. The canal typically obliterates early in life, but in some cases the canal can partially or completely fail to close, potentially resulting in a hydrocele or hernia of pelvic contents. Recognition of this entity is especially important in cases of ovarian hernia due to the risk of incarceration and torsion. We aim to increase awareness of this condition by reviewing the embryology, anatomy and diagnosis of canal of Nuck disorders with imaging findings on US, CT and MRI using several cases from a single institution. (orig.)
Type III apical transportation of root canal

Directory of Open Access Journals (Sweden)

Shiv P Mantri

2012-01-01

Full Text Available Procedural accidents leading to complications such as canal transportation have been ascribed to inapt cleaning and shaping concepts. Canal transportation is an undesirable deviation from the natural canal path. Herewith a case of apical transportation of root canal resulting in endodontic retreatment failure and its management is presented. A healthy 21-year-old young male presented discomfort and swelling associated with painful endodontically retreated maxillary incisor. Radiograph revealed periradicular radiolucency involving underfilled 11 and overfilled 12. Insufficiently obturated 11 exhibited apical transportation of canal. This type III transportation was treated by periradicular surgery and repair using white mineral trioxide aggregate (MTA. Comfortable asymptomatic patient presented uneventful healing at third and fourth month recall visits. A decrease in the size of radiolucency in radiograph supported the clinical finding. In the present case, MTA is useful in repairing the transportation defect. The result of these procedures is predictable and successful.

Cerro Bombero: registro de Hippidion saldiasi Roth, 1899 (Equidae, Perissodactyla en el Holoceno temprano de Patagonia (Santa Cruz, Argentina

Directory of Open Access Journals (Sweden)

Alberdi, M. T.

2008-06-01

Full Text Available A new record of Hippidion saldiasi with new radiocarbon data referred to early Holocene (8,850 Â± 80 year C-14 B.P of Patagonia is reported. Both its peculiar geographic location in a scarcely prospected zone and its radiocarbon age, provide new elements to discuss the previous hypotheses about the extinction of the horses and its relations with the human beings that inhabited the different environments of South America.Presentamos un nuevo registro de Hippidion saldiasi con datación radiocarbónica directa correspondiente al Holoceno temprano de Patagonia (8.850 Â± 80 años C-14 AP. Su particular ubicación temporal y geográfica en una zona poco estudiada hasta ahora y su registro reciente, aportan nuevos elementos para discutir las hipótesis previas sobre la extinción de los caballos y su relación con los grupos humanos que colonizaron los diferentes ambientes de América del Sur.
Mandibular molar with five root canals.

Science.gov (United States)

Barletta, Fernando Branco; Dotto, Sidney Ricardo; Reis, Magda de Sousa; Ferreira, Ronise; Travassos, Rosana Maria Coelho

2008-12-01

The purpose of this study was to demonstrate the importance of knowledge of the internal anatomy of root canals for the success of endodontic treatment. Lack of knowledge of anatomic variations and their characteristics in different teeth has been pointed out as one of the main causes of endodontic therapy failure. In this report, the authors describe the endodontic treatment of a mandibular first molar with five root canals, evaluate the rate of occurrence of this number of canals, and discuss the importance of their identification and treatment.
Lumbar Vertebral Canal Diameters in Adult Ugandan Skeletons ...

African Journals Online (AJOL)

Background: Normal values of lumbar vertebral canal diameters are useful in facilitating diagnosis of lumbar vertebral canal stenosis. Various studies have established variation on values between different populations, gender, age, and ethnic groups. Objectives: To determine the lumbar vertebral canal diameters in adult ...
Impact of canal water shortages on groundwater in the Lower Bari Doab Canal system in Pakistan

International Nuclear Information System (INIS)

Shakir, A.S.; Rehman, H.U.; Khan, N.M.; Qazi, A.U.

2011-01-01

This paper presents rigorous analysis of shortage of canal water supplies, crop water requirements, and groundwater use and its quality in the command of Lower Bari Doab Canal, Pakistan. The annual canal water supplies are 36% less than the crop water requirements. This shortage further increases to 56% if actual canal supplies (averaged over last ten years) are compared with the crop water requirement. The groundwater levels are depleting at the rate of 30 to 40 cm per year in most parts of the LBDC command and this tendency of lowering may increase in future due to further increase in crop water requirements. The analysis of data for the last seven years indicate that quality of groundwater in most parts of LBDC command is generally good (64% of the area) or marginally acceptable (28%) for irrigation use. However, declining trends in groundwater quality are visible and can create long term sustain ability problems if proper remedial actions are not taken well in time. (author)
Gender and laterality in semicircular canal dehiscence syndrome.

Science.gov (United States)

Karimnejad, K; Czerny, M S; Lookabaugh, S; Lee, D J; Mikulec, A A

2016-08-01

To determine if there is gender or laterality predilection in patients with semicircular canal dehiscence syndrome. A multi-institutional chart review was performed to identify patients diagnosed with semicircular canal dehiscence between 2000 and 2015. A systematic literature search was conducted using PubMed to further identify patients with semicircular canal dehiscence. Age, gender and laterality data were collected. Statistical analysis was performed to evaluate for gender or laterality preponderance. A total of 682 patients with semicircular canal dehiscence were identified by literature and chart review. Mean age of diagnosis was 49.75 years (standard deviation = 15.33). Semicircular canal dehiscence was associated with a statistically significant female predominance (chi-square = 7.185, p = 0.007); the female-to-male ratio was 1.2 to 1. Left-sided semicircular canal dehiscence was most common, followed by right-sided then bilateral (chi-square = 23.457, p < 0.001). Semicircular canal dehiscence syndrome is most commonly left-sided and exhibits a female predominance. This may be secondary to morphological cerebral hemisphere asymmetries in both sexes and a predilection of women to seek more medical care than men.
Soñar con el futuro. Proyectos inmigratorios para la Patagonia argentina en Teodoro Alemann y Roberto J. Payró

Directory of Open Access Journals (Sweden)

Jennifer M. Valko

2014-06-01

Taking into account recent studies on journalistic travel and Argentine nation building, this article examines the profile of a type of reporter that has been studied to a lesser degree, the immigrant journalist. It analyzes two travel chronicles about Patagonia published in Buenos Aires in 1898: Ein Ausflug nach dem Chubut-Territorium [An Excursion to the Chubut Territory] by Swiss journalist Theodor Alemann, published in the German-language newspaper Argentinisches Tageblatt [Argentine Daily], and La australia argentina, by Roberto J. Payró which appeared in La Nación. In both chronicles the narration of the trip to Patagonia is interrupted at a key moment by the telling of a dream regarding the future of the region. This essay demonstrates that these oneiric digressions reveal political and economic interests contrary to the official Argentine plans for the development of the region, the role of immigrants and their relationship with European powers.
Environmental pollution and shipping feasibility of the Nicaragua Canal

International Nuclear Information System (INIS)

Chen, Jihong; Zeng, Xin; Deng, Yibing

2016-01-01

In recent years, the Nicaraguan government's renewed interest in constructing this interoceanic canal has once again aroused widespread concern, particularly in the global shipping industry. The project's immense ecological risks, coupled with the recent expansions of both the Panama Canal and the Suez Canal, have raised questions among scientists and experts about its viability. Whether the Nicaragua Canal is really feasible for international shipping, given its high marine pollution risks, requires the further study. This paper discusses and analyses the feasibility of the Nicaragua Canal in the context of its environmental impact and value as a shipping service. This paper aims to provide an important information reference to inform strategic decision-making among policymakers and stakeholders. Our research results indicate that the environmental complexity, economic costs and safety risks of building a new transoceanic canal are simply too high to justify the project. - Highlights: • The Nicaragua Canal is a long-standing controversial maritime project. • We develop specific analysis of the high environmental pollution risks of the canal. • The shipping service feasibility of the canal is faced with great uncertainty. • The government and stakeholders are suggested to be discreet to the mega project.
Conflictos ecoterritoriales transfronterizos y megaproyectos extractivistas en cuencas compartidas de la Patagonia; Conflitos ecoterritoriais transfronteiriços e megaprojetos extrativistas nas bacias da Patagônia; Cross-border Eco-territorial Conflicts and Extractivist Megaprojects in the Patagonia River Basins

Directory of Open Access Journals (Sweden)

Bárbara Jerez Henríquez

2015-01-01

Full Text Available Resumen: Las cuencas transfronterizas de la Patagonia Andina argentino- chilena en los útimos 15 años se ha convertido en un espacio transnacional en el que aterrizan megaproyectos de minería y represas hidroeléctricas que conllevan importantes impactos en los ecosistemas, economías y culturas locales, como parte de una tendencia en América Latina orientada al avance de las territorialidades extractivistas hacia zonas fronterizas que además significa transgredir marcos legales previos para el manejo de cuencas compartidas. En ese contexto emergen fuertes procesos de resistencia desde diversas narrativas que en su conjunto reivindican otras territorialidades en estas cuencas abarcando escalas locales y transfronterizas que plantean nuevos debates y desafíos para discutir los conflictos ecoterritoriales que emergen en zonas de fronteras. Palabras clave: extractivismo, cuencas, fronteras, territorialidades, Patagonia. Resumo: As bacias transfronteiriças da Patagônia Andina Argentino-chilena nos últimos 15 anos se converteram em um espaço transnacional em que aterrissam mega-projetos de mineração e represas hidroelétricas que conduzem importantes impactos nos ecossistemas, economias e culturas locais, como parte de uma tendência na América Latina de avanço das territorialidades extrativistas em direção a zonas fronteiriças que, além de tudo, significam transgredir marcos legais para o manejo de bacias divididas. Nesse contextos emergem fortes processos de resistência desde diversas narrativas que em seu conjunto reivindicam outras territorialidades nestas bacias cobrindo escalas locais e transfronteiriças que colocam novos debates e desafios para se discutir os conflitos ecoterritoriais que emergem nas zonas de fronteira. Palavras-chave: extrativismo, bacias, fronteiras, territorialidade, Patagônia. Abstract: The cross-border river basins of the Argentine-Chilean Andean Patagonia have
De Patagonia a Budapest: caminos europeos de fósiles santacrucenses (1845-1956)

OpenAIRE

Vizcaíno, Sergio Fabián; Bargo, M. Susana

2013-01-01

A fines del siglo XIX y principios del XX, acicateados por los descubrimientos de los hermanos Ameghino, los paleontólogos evolucionistas de América del Norte y Europa posaron sus ojos en los mamíferos fósiles de Patagonia. Mientras los primeros organizaron expediciones, los europeos se valieron mayormente de otras formas comunes en la época para hacer colecciones de historia natural, como el intercambio y la compra. En el viejo continente, el devenir de los fósiles patagónicos no escapó a la...
The failures of root canal preparation with hand ProTaper.

Science.gov (United States)

Bătăiosu, Marilena; Diaconu, Oana; Moraru, Iren; Dăguci, C; Tuculină, Mihaela; Dăguci, Luminiţa; Gheorghiţă, Lelia

2012-07-01

The failures of root canal preparation are due to some anatomical deviation (canal in "C" or "S") and some technique errors. The technique errors are usually present in canal root cleansing and shaping stage and are the result of endodontic treatment objectives deviation. Our study was made on technique errors while preparing the canal roots with hand ProTaper. Our study was made "in vitro" on 84 extracted teeth (molars, premolars, incisors and canines). The canal root of these teeth were cleansed and shaped with hand ProTaper by crown-down technique and canal irrigation with NaOCl(2,5%). The dental preparation control was made by X-ray. During canal root preparation some failures were observed like: canal root overinstrumentation, zipping and stripping phenomenon, discarded and/or fractured instruments. Hand ProTaper represents a revolutionary progress of endodontic treatment, but a deviation from accepted rules of canal root instrumentation can lead to failures of endodontic treatment.
Especies forestales promisorias para la diversificación de forestaciones en la Patagonia Argentina

OpenAIRE

Godoy, María Marcela; Defossé, Guillermo E; Thren, Martin

2007-01-01

En el oeste de la Patagonia argentina existen aproximadamente 70 mil hectáreas forestadas, de las cuales el 80% corresponde a Pinus ponderosa y el resto a Pseudotsuga menziesii y Pinus contorta. Con el objetivo de evitar esta tendencia hacia los monocultivos con sus consecuencias ecológicas y sanitarias desfavorables, surge la necesidad de evaluar la posibilidad de cultivar otras especies forestales que permitan la diversificación de las actuales forestaciones. En este trabajo se analizaron p...
Infected Hydrocele of the Canal of Nuck

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Parkash Mandhan

2013-01-01

Full Text Available Hydrocele of the canal of Nuck in children is rare. It may present as incarcerated inguinal hernia and necessitates emergency exploration. Risk of infection in hydrocele of the canal of nuck is very rare. We present a case report of a 5-year-old girl who presented with a left tender inguinolabial region swelling with fever, tachycardia, and mild dehydration. The clinical features were suggestive of strangulated left inguinal hernia and further imaging and surgical exploration revealed it to be an infected hydrocele of the canal of Nuck. High ligation and hydrocelectomy were performed. Hydrocele of the canal of Nuck in a female child presenting with an inguinal swelling should be considered in differential diagnosis.
Incidence and characteristics of mandibular accessory canals: A radiographic investigation.

Science.gov (United States)

Borgonovo, Andrea Enrico; Taschieri, Silvio; Vavassori, Virna; Re, Dino; Francetti, Luca; Corbella, Stefano

2017-11-01

The aim of the present study was to explore, through tridimensional reconstructions of cone-beam computed tomography (CBCT) scans, the presence and the characteristics of mandibular accessory canals. For each included participant, the presence of accessory canals was recorded. The diameter of the canal, as well as the distance between the canal walls and the walls of the mandibular bone (lingual, buccal, cranial and caudal), were measured and recorded. Mandibular accessory canals could be found in 8.8% of participants. Retromolar canals were the most frequently found accessory mandibular canals. Accessory mandibular canals were found in a relatively high number of participants through the examination of CBCT scans and tridimensional reconstruction. The presence of such structures should be considered cautiously when planning and performing surgical interventions in mandibular area. © 2017 John Wiley & Sons Australia, Ltd.
21 CFR 872.3820 - Root canal filling resin.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal filling resin. 872.3820 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of material, such as methylmethacrylate, intended...
A 17-year Record of Meteorological Observations Across the Gran Campo Nevado Ice Cap in Southern Patagonia, Chile, Related to Synoptic Weather Types and Climate Modes

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Stephanie S. Weidemann

2018-05-01

Full Text Available The network of long-term meteorological observations in Southernmost Patagonia is still sparse but crucial to improve our understanding of climatic variability, in particular in the more elevated and partially glaciated Southernmost Andes. Here we present a unique 17-year meteorological record (2000–2016 of four automatic weather stations (AWS across the Gran Campo Nevado Ice Cap (53°S in the Southernmost Andes (Chile and the conventional weather station Jorge Schythe of the Instituto de la Patagonia in Punta Arenas for comparison. We revisit the relationship between in situ observations and large-scale climate models as well as mesoscale weather patterns. For this purpose, a 37-year record of ERA Interim Reanalysis data has been used to compute a weather type classification based on a hierarchical correlation-based leader algorithm. The orographic perturbation on the predominantly westerly airflow determines the hydroclimatic response across the mountain range, leading to significant west-east gradients of precipitation, air temperature and humidity. Annual precipitation sums heavily drop within only tens of kilometers from ~7,500 mm a−1 to less than 800 mm a−1. The occurrence of high precipitation events of up to 620 mm in 5 days and wet spells of up to 61 consecutive days underscore the year-around wet conditions in the Southernmost Andes. Given the strong link between large-scale circulation and orographically controlled precipitation, the synoptic-scale weather conditions largely determine the precipitation and temperature variability on all time scales. Major synoptic weather types with distinct low-pressure cells in the Weddell Sea or Bellingshausen Sea, causing a prevailing southwesterly, northwesterly or westerly airflow, determine the weather conditions in Southernmost Patagonia during 68% of the year. At Gran Campo Nevado, more than 80% of extreme precipitation events occur during the persistence of these weather types. The
Mejoras en el canal de Panamá

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Brandl, Charles McG.

1963-07-01

Full Text Available The Panama Canal, together with the Suez Canal, is an engineering accomplishment which is now regarded as a master work marking the initiation of modern civil engineering. Other projects, also of great magnitude, do not seem to maintain the reputation of the above two, because they cannot continue to serve their function with sustained usefulness in the new circumstances of today. The Panama Canal, with its limited dock capacity, and the narrow, so called Serpent, canal, has had to cope with a continuously increasing volume of shipping traffic; a natural consequence of commercial evolution. In order to keep up with these increasing demands, it has been necessary to carry out an almost uninterrupted series of modifications and improvements, affecting both the method of operation and organisation, and the actual nature of the canal. Thanks to these alterations the Panama Canal has continued to maintain, at least nominally, an adequate standard of functional efficiency. At present the canal is being widened over certain sections to enable the easy passage of ships of great displacement. The work is being done very rapidly, and in order to gain time, it has been distributed to various contractors simultaneously.El canal a través del ismo de Panamá es una obra de ingeniería civil que, junto con el de Suez, empiezan ya a clasificarse como obras maestras que señalan el primer jalón del desarrollo de la ingeniería moderna. Otras obras, también importantes, no conservan, sin embargo, la misma reputación que aquéllas, por no seguir un paralelismo con las exigencias en cada época. El canal de Panamá, con sus exclusas, y angosto paso llamado de la. Culebra, ha tenido que afrontar un tráfico creciente de navíos que siguen la evolución del tiempo. Para conseguir este paralelismo, tanto el material de explotación como la organización, dragados y mejoras, han tenido que conocer una sucesión ininterrumpida de modificaciones que han permitido
Comparison of the rheological properties of four root canal sealers

Institute of Scientific and Technical Information of China (English)

Seok Woo Chang; Kwang Shik Bae; Young-Kyu Lee; Qiang Zhu; Won Jun Shon; Woo Cheol Lee; Kee Yeon Kum; Seung Ho Baek; In Bog Lee; Bum-Soon Lim

2015-01-01

The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four root canal sealers, measured using the simple press method (ISO 6876), and their viscosities, measured using a strain-controlled rheometer. A newly developed, calcium phosphate-based root canal sealer (Capseal) and three commercial root canal sealers (AH Plus, Sealapex and Pulp Canal Sealer EWT) were used in this study. The flowabilities of the four root canal sealers were measured using the simple press method (n55) and their viscosities were measured using a strain-controlled rheometer (n55). The correlation between these two values was statistically analysed using Spearman’s correlation test. The flow diameters and the viscosities of the root canal sealers were strongly negatively correlated (r520.8618). The viscosity of Pulp Canal Sealer EWT was the lowest and increased in the following order:AH Plus,Sealapex,Capseal (P,0.05). All of the tested root canal sealers showed characteristic time-and temperature-dependent changes in their rheological properties. The viscosities measured using the strain-controlled rheometer were more precise than the flowabilities measured using the simple press method, suggesting that the rheometer can accurately measure the rheological properties of root canal sealers.
Management of Acquired Atresia of the External Auditory Canal.

Science.gov (United States)

Bajin, Münir Demir; Yılmaz, Taner; Günaydın, Rıza Önder; Kuşçu, Oğuz; Sözen, Tevfik; Jafarov, Shamkal

2015-08-01

The aim was to evaluate surgical techniques and their relationship to postoperative success rate and hearing outcomes in acquired atresia of the external auditory canal. In this article, 24 patients with acquired atresia of the external auditory canal were retrospectively evaluated regarding their canal status, hearing, and postoperative success. Acquired stenosis occurs more commonly in males with a male: female ratio of 2-3:1; it seems to be a disorder affecting young adults. Previous ear surgery (13 patients, 54.2%) and external ear trauma (11 patients, 45.8%) were the main etiological factors of acquired ear canal stenosis. Mastoidectomy (12/13) and traffic accidents (8/11) comprise the majority of these etiological factors. Endaural incision is performed in 79.2% and postauricular incision for 20.8% of cases during the operation. As types of surgical approach, transcanal (70.8%), transmastoid (20.8%), and combined (8.4%) approaches are chosen. The atretic plate is generally located at the bony-cartilaginous junction (37.5%) and in the cartilaginous canal (33.3%); the bony canal is involved in a few cases only. Preserved healthy canal skin, split- or full-thickness skin grafts, or pre- or postauricular skin flaps are used to line the ear canal, but preserved healthy canal skin is preferred. The results of surgery are generally satisfactory, and complications are few if surgical principles are followed.
Chronological study of the pre-jurassic basement rocks of southern Patagonia

International Nuclear Information System (INIS)

Pankhurst, R.J; Rapela, C.W; Loske, W.P; Fanning, C.M

2001-01-01

Southern Patagonia east of the Andes was the site of extensive rhyolite volcanism during the Jurassic rifting of Gondwana and subsequent shallow marine basin formation during the Cretaceous. Thus exposures of pre-Jurassic basement are extremely sparse. Nevertheless, extraction of the maximum amount of information from these scattered outcrops of granite and metamorphic rocks is crucial to assessment of the Palaeozoic and earliest Mesozoic history and crustal structure of the Pacific margin of the supercontinent. In particular, the identification and possible correlation of early terrane accretion on this margin depends on comparison of pre-Jurassic igneous and metamorphic events with adjacent areas. This is a preliminary report on work now in progress to this end (au)
Sweet cherries from the end of the world: options and constraints for fruit production systems in South Patagonia, Argentina

NARCIS (Netherlands)

Cittadini, E.D.

2007-01-01

In South Patagonia, development of the fruit production sector has been almost exclusively based on the production of sweet cherry, with an area increase from 176 ha in 1997 to 578 ha at the end of 2006. These orchards are designed as intensive systems and oriented to export markets. Even though

Middle mesial canals in mandibular molars: incidence and related factors.

Science.gov (United States)

Nosrat, Ali; Deschenes, Raney J; Tordik, Patricia A; Hicks, M Lamar; Fouad, Ashraf F

2015-01-01

Although the internal anatomy of mandibular molars has been extensively studied, information about middle mesial (MM) canals is limited. The primary aim of this retrospective study was to evaluate the incidence of MM canals in mandibular first and second molars. The secondary aim was to correlate the incidence of MM canals with variables of molar type, sex, age, ethnicity, and presence of a second distal canal. All mature permanent first and second mandibular molars treated from August 2012 to May 2014 were included in the analysis. After completion of root canal instrumentation in all main canals, the clinician inspected the isthmus area of the mesial root using the dental operating microscope. If there was a catch point in this area with a file or explorer, the operator spent more time attempting to negotiate an MM canal. Seventy-five mandibular first and second molars were treated during the specified period. Fifteen (20%) teeth had negotiable MM canals. The incidence of MM canals was 32.1% in patients ≤ 20 years old, 23.8% in patients 21-40 years old, and 3.8% in patients > 40 years. Analysis of data revealed a significant difference in the distribution of MM canals among different age groups (P molar type, and presence of a second distal canal were not significant. The incidence of negotiable MM canals overall and their frequency of identification in younger patients were higher than in previous reports. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Madera de Pinus ponderosa en Patagonia Argentina : Jornada Forestal Tecnológica

OpenAIRE

Refort, María Mercedes; Keil, Gabriel Darío; Spavento, Elena

2013-01-01

El día 15 de noviembre de 2012 se realizó en el Edificio de Bosques de la Facultad de Ciencias Agrarias y Forestales de la UNLP, la Primera Jornada Tecnológica sobre Madera de Pinus ponderosa en Patagonia Argentina, destinadas a profesionales de diferentes áreas, estudiantes, investigadores y docentes. Las Jornadas fueron organizadas por el Laboratorio de Investigaciones en Madera (LIMAD) y la Secretaría de Investigaciones de la Facultad de Ciencias Agrarias y Forestales, UNLP y auspiciadas p...
Radiographic evaluation of the quality of root canal obturation of single-matched cone Gutta-percha root canal filling versus hot lateral technique

Directory of Open Access Journals (Sweden)

Randa Suleiman Obeidat

2014-01-01

Full Text Available Aim: The aim of this study is to evaluate radiographically the quality of root canal filling in mesiodistal and buccolingual view when comparing matched cone condensation and warm lateral Gutta-percha condensation using system B heating instrument in a low-heat warm lateral condensation technique in0 vitro. Materials and Methods: A total of 40 mandibular premolars with straight single canals were divided into two groups with 20 each. The root canals were shaped by hand file and Revo-S rotary files to size (25, 0.06 at the end point, then they filled by Gutta-percha cone and meta-seal sealer. In group A, a single matched cone technique was used to fill the root canals. In group B, a hot lateral condensation using system B instrument at 101°C was performed. Result: The result of this study showed no significant difference in density of Gutta-percha fill in apical and coronal two-third when comparing matched cone root canal filling and hot lateral technique (P > 0.05. The only significant difference (P < 0.05 was in matched cone between buccolingual and mesiodistal view in the coronal two-third. Conclusion: Within the limitation of this study, single matched cone technique has a good density in the apical one-third as that of the hot lateral technique so it may be used for filling narrow canals. In the coronal two-third of the root canal, single matched cone technique showed inferior density of root canal filling which can be improved by using accessory cones Gutta-percha in wide canal.
Newer Root Canal Irrigants in Horizon: A Review

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Sushma Jaju

2011-01-01

Full Text Available Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.
Mercury in lichens of Nahuel Huapi National Park, Patagonia, Argentina

International Nuclear Information System (INIS)

Ribeiro Guevara, S.; Bubach, D.; Arribere, M.; Nacional de Cuyo Universidad, Bariloche

2004-01-01

Mercury and other elements of interest are determined in lichens collected in Nahuel Huapi National Park, Northern Patagonia, Argentina. Pooled samples are analyzed by instrumental neutron activation analysis. Mercury contents in Usnea sp. collected from undisturbed sites range from 0.0558 ± 0.0083 to 1.38 ± 0.18 μg x g -1 . Other potential pollutants are identified by the analysis of Usnea sp. samples, namely Sb, As, Br, Zn, and Se. Previous experiments with foliose and fruticose lichens are also discussed. The analysis of mercury contents of foliose lichens sampled from urban and periurban sites of Bariloche city, and from undisturbed regions, demonstrate that the atmosphere of Bariloche city is enriched in mercury compared to the surroundings. The result is confirmed by transplantation experiments from undisturbed zones to urban sites. (author)
Capacity building for freshwater insect studies in northern Patagonia, Argentina: DARWIN Initiative programme

Directory of Open Access Journals (Sweden)

Stephen J. BROOKS

2009-01-01

Full Text Available Este proyecto fue financiado durante un período de tres años, desde septiembre de 2006 a través de la Iniciativa Darwin del gobierno Británico. El objetivo de este trabajo es el estudio de los insectos acuáticos del Parque Nacional Nahuel Huapi (PNNHP, Patagonia, Argentina. El parque incluye una gran variedad de hábitats que comprenden arroyos, ríos y lagos los cuales se distribuyen desde el bosque siempreverde frío, hasta la zona árida de estepa. Todo el material será identificado y depositado en las colecciones del Museo La Plata y el Museo de Historia Natural de Londres. Los fondos de la Iniciativa Darwin han sido utilizados para equipar un laboratorio de biodiversidad en las oficinas del PNNHP en Bariloche y la estación de investigación en Puerto Blest. Toda la información de los insectos acuáticos y las distintas formaciones vegetales donde éstos se han encontrado, se incluirá en una base de datos (la primera de su tipo en Patagonia que utilizará la metodología GIS para analizar patrones de distribución de las especies en el parque. En estos momentos se están produciendo varias guías de campo para identificar los insectos acuáticos del PNNHP. Es nuestro deseo que los resultados obtenidos en este proyecto, contribuyan a la conservación de los sistemas acuáticos en Argentina y América del Sur
Neuronal hyperplasia in the anal canal

DEFF Research Database (Denmark)

Fenger, C; Schrøder, H D

1990-01-01

In a consecutive series of minor surgical specimens from the anal canal, neuronal hyperplasia was found in nine of 56 haemorrhoidectomy specimens and in four of 23 fibrous polyps. In an additional series of 14 resections of the anal canal, neuronal hyperplasia was present in six cases, of which f...
THE BUSINESS OF THE CANAL: THE ECONOMICS AND POLITICS OF THE CARTER ADMINISTRATION’S PANAMA CANAL ZONE INITIATIVE, 1978

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Mary C. Swilling

2004-01-01

Full Text Available The Carter-Torrijos Treaty of 1978, the initiative to relinquish controi of the Panama Canal Zone to the Republic of Panama, allowed Panama for the first time in its short history to become an autonomous nation and to take control of its destiny as a global trading crossroads. Conservatives rallied against President Carter and accused him of jeopardizing U. S. security and hegemony. Fears were that Panama did not have the economic or technical resources to maintain Canal operations, lacked the administrative knowledge and resources to manage the business of the Canal, lacked the military presence to insure security of the Canal, and did not have the political and social will to maintain the environmental integrity of the region. In short, disastrous results were predicted. Carter prevailed. December 31, 1999 saw the surrender of the Canal Zone, and all its facilities, to Panama. This paper discusses events that precipitated Carter’s decision, economic and political arguments presented during the 1977-78 debate, implementation of the treaty, and an evaluation of the ‘business of the Canal’ today.
Hydrology and environmental aspects of Erie Canal (1817-99)

Science.gov (United States)

Langbein, Walter Basil

1976-01-01

As the first major water project in the United States, the old Erie Canal provides an example of the hydrological and environmental consequences of water development. The available record shows that the project aroused environmental fears that the canal might be impaired by the adverse hydrologic effects of land development induced by the canal. Water requirements proved greater than anticipated, and problems of floods and hydraulic inefficiencies beset navigation throughout its history. The Erie Canal proved the practicality of major hydraulic works to the extent that operations and maintenance could cope with the burdens of deficiencies in design. The weight of prior experience that upland streams, such as the Potomac and Mohawk Rivers, had proved unsatisfactory for dependable navigation, led to a decision to build an independent canal which freed the location from the constraints of river channels and made possible a cross-country water route directly to Lake Erie. The decision on dimensioning the canal prism--chiefly width and depth-involved balance between a fear of building too small and thus not achieving the economic potentials, and a fear of building too expensively. The constraints proved effective, and for the first part of its history the revenues collected were sufficient to repay all costs. So great was the economic advantage of the canal that the rising trend in traffic soon induced an enlargement of the canal cross section, based upon a new but riskier objective-build as large as the projected trend in toll revenues would finance. The increased revenues did not materialize. Water supplies were a primary concern for both the planners and the operators of the canal. Water required for lockage, although the most obvious to the planners, proved to be a relatively minor item compared with the amounts of water that were required to compensate for leakage through the bed and banks of the canal. Leakage amounted to about 8 inches of depth per day. The total
Single-rooted maxillary first molar with a single canal: endodontic retreatment.

Science.gov (United States)

de la Torre, Francisco; Cisneros-Cabello, Rafael; Aranguren, José Luis; Estévez, Roberto; Velasco-Ortega, Eugenio; Segura-Egea, Juan José

2008-12-01

This case report presents an unusual root canal system in a maxillary first molar tooth: a single canal in a single root. The endodontic access cavity displayed only 1 canal orifice. This case demonstrated that: 1) clinicians must have adequate knowledge about root canal morphology and its variations; 2) the location and morphology of root canals should be identified radiologically before the root canal treatment; and 3) careful examination of radiographs and the internal anatomy of teeth is essential.
Saccharomyces eubayanus and Saccharomyces uvarum associated with the fermentation of Araucaria araucana seeds in Patagonia.

Science.gov (United States)

Rodríguez, M Eugenia; Pérez-Través, Laura; Sangorrín, Marcela P; Barrio, Eladio; Lopes, Christian A

2014-09-01

Mudai is a traditional fermented beverage, made from the seeds of the Araucaria araucana tree by Mapuche communities. The main goal of the present study was to identify and characterize the yeast microbiota responsible of Mudai fermentation as well as from A. araucana seeds and bark from different locations in Northern Patagonia. Only Hanseniaspora uvarum and a commercial bakery strain of Saccharomyces cerevisiae were isolated from Mudai and all Saccharomyces isolates recovered from A. araucana seed and bark samples belonged to the cryotolerant species Saccharomyces eubayanus and Saccharomyces uvarum. These two species were already reported in Nothofagus trees from Patagonia; however, this is the first time that they were isolated from A. araucana, which extends their ecological distribution. The presence of these species in A. araucana seeds and bark samples, led us to postulate a potential role for them as the original yeasts responsible for the elaboration of Mudai before the introduction of commercial S. cerevisiae cultures. The molecular and genetic characterization of the S. uvarum and S. eubayanus isolates and their comparison with European S. uvarum strains and S. eubayanus hybrids (S. bayanus and S. pastorianus), allowed their ecology and evolution us to be examined. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.
The failures of root canal preparation with hand ProTaper

OpenAIRE

Bătăiosu, Marilena; Diaconu, Oana; Moraru, Iren; Dăguci, C.; Ţuculină, Mihaela; Dăguci, Luminiţa; Gheorghiţă, Lelia

2012-01-01

The failures of root canal preparation are due to some anatomical deviation (canal in “C” or “S”) and some technique errors. The technique errors are usually present in canal root cleansing and shaping stage and are the result of endodontic treatment objectives deviation. Objectives: Our study was made on technique errors while preparing the canal roots with hand ProTaper. Methodology: Our study was made “in vitro” on 84 extracted teeth (molars, premolars, incisors and canines). The canal roo...
Root canal treatment of mandibular second premolar tooth with taurodontism

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Vujašković Mirjana

2008-01-01

Full Text Available INTRODUCTION Taurodontism is a morphoanatomical change in the shape of a tooth. An enlarged body of a tooth with smaller than usual roots is a characteristic feature. Internal tooth anatomy correlates with this appearance, which means that a taurodontal tooth has a large pulp chamber and apically positioned furcations. This dental anomaly may be associated with different syndromes and congenital discoders. CASE OUTLINE The case report presents the patient of a rare case of taurodontism in the mandibular second premolar with chronic periodontitis. Endodontic treatment was performed after dental history and clinical examination. Special care is required in all segments of endodontic treatment of a taurodontal tooth from the identification orifice, canal exploration, determining working length, cleaning and shaping and obturation of the root canal. Precurved K-file was used for canal exploration and location of the furcation. One mesial and one distal canal with the buccal position were identified in the apical third of the root canal. The working lengths of two canals were determined by radiographic interpretation with two K-files in each canal and verified with the apex locator. During canal instrumentation, the third canal was located in the disto-lingual position. The working length of the third canal was established using the apex locator. CONCLUSION Thorough knowledge of tooth anatomy and its variations can lead to lower percentage of endodontic failure. Each clinical case involving these teeth should be investigated carefully, clinically and radiographically to detect additional root canals. High quality radiographs from different angles and proper instrumentarium improve the quality of endodontic procedure.
[Upper lateral incisor with 2 canals].

Science.gov (United States)

Fabra Campos, H

1991-01-01

Clinical case summary of the patient with an upper lateral incisor with two root canals. The suspicion that there might be an anatomic anomaly in the root that includes a complex root canal system was made when an advanced radicular groove was detected in the lingual surface or an excessively enlarged cingulum.
Environmental pollution and shipping feasibility of the Nicaragua Canal.

Science.gov (United States)

Chen, Jihong; Zeng, Xin; Deng, Yibing

2016-12-15

In recent years, the Nicaraguan government's renewed interest in constructing this interoceanic canal has once again aroused widespread concern, particularly in the global shipping industry. The project's immense ecological risks, coupled with the recent expansions of both the Panama Canal and the Suez Canal, have raised questions among scientists and experts about its viability. Whether the Nicaragua Canal is really feasible for international shipping, given its high marine pollution risks, requires the further study. This paper discusses and analyses the feasibility of the Nicaragua Canal in the context of its environmental impact and value as a shipping service. This paper aims to provide an important information reference to inform strategic decision-making among policymakers and stakeholders. Our research results indicate that the environmental complexity, economic costs and safety risks of building a new transoceanic canal are simply too high to justify the project. Copyright © 2016 Elsevier Ltd. All rights reserved.
Assessment of periapical health, quality of root canal filling, and ...

African Journals Online (AJOL)

Sixty three teeth were found to have short root canal fillings, whereas 74 teeth had adequate root canal fillings, and the remaining 10 teeth had over extended root canal filling. A significant correlation was observed between the length of root filling and apical periodontitis (P = 0,023). Inadequately dense root canal filling was ...
Endodontic management of a permanent mandibular first molar with six canals

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Mohammad Ahmad Alenezi

2016-01-01

Full Text Available An excellent knowledge of root canal anatomy of teeth is a golden standard for the successful clinical outcome of root canal therapy. Several anatomic variations may occur in a permanent mandibular first molar. Usually, three to four root canals are found, but six to eight canals have been reported. A 22-year-old Bangladeshi woman was referred for endodontic treatment of mandibular right first molar. Rigorous clinical examination revealed the presence of three canals in mesial root and three canals in distal root as well. The dentists should expect any variation in root canal system and use the diagnostic tools to manage the cases.
MRI diagnosis of intraspinal dermoid ruptured into central spinal canal

International Nuclear Information System (INIS)

Zhang Yong; Cheng Jingliang; Wang Juan; Li Huali; Ren Cuiping; Zhang Yan; Gao Xuemei

2009-01-01

Objective: To evaluate the appearances of intraspinal dermoid ruptured into the central spinal canal, as well as the MRI diagnosis and differential diagnosis. Methods: Eleven cases of intraspinal dermoid ruptured into the central spinal canal were reviewed. Six cases underwent whole spine MRI scan, 2 cases with thoracic and lumbar spine MRI, as well as 3 cases only with lumbar spine MRI. Results: Free fat droplets within spinal cord central canal demonstrated high signal intensity on T 1 WI, slight declined signal intensity on T 2 WI, and extremely low signal on fat suppression sequence. Of the 11 cases, 2 cases broke into neighboring central spinal canal of the dermoid, 3 cases scattered within thoracic spinal cord central canal, 4 cases discontinuously distributed in the whole spinal cord central canal, 2 cases showed continuous distribution. Conclusion: Intraspinal dermoid ruptured in the central spinal canal had specific appearance on MRI, when a dermoid tumor is suspected, MRI of the entire spine were recommended to detect possible leakage of' fat within central spinal canal. (authors)
La proyección colonial de Chile a la Patagonia Insular en el siglo XVIII

OpenAIRE

Urbina Carrasco, María Ximena

2011-01-01

In this article, the geopolitical consequences of the shipwreck of the English frigate Wager and the landfall of the ship Anna into the coasts of the Western Insular Patagonia in 1741 are presented, which were part of the fleet of George Anson. The news reporting the English presence in the deserted and unknown insular and coastal territory southernmost Chiloé, and which had disseminated towards the end of the continent, promoted the deployment of different actions tending to make presence no...
Three root canals in the maxillary second premolar

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de Almeida-Gomes Fabio

2009-01-01

Full Text Available In this study, we report an endodontic treatment of the maxillary second premolar with three root canals and distinct foramens. The possibility of three root canals in this tooth is quite small; however, it must be taken into account in clinical and radiographic evaluation during endodontic treatment. Many times, their presence is noticed only after canal treatment due to continuing post-operative discomfort.

The crazy project – Canal Istanbul

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Seda Kundak

2011-10-01

Full Text Available It was late April 2011 when “the Crazy Project - Canal Istanbul” was proposed by the Prime Minister of Turkey, during his election campaign. Although the idea of an artificial canal is not new, since it is initiated without any consensus between the people and institutions in Istanbul, the project immediately set a large number of debates. These vary from the legitimacy of decentralization of governance, to potential impacts of the canal on international politics, economy, environment and urban life. Regarding past infrastructure projects in Istanbul, such large scale investments have caused extensive acceleration in construction sector in one hand and social and economic shifts on the other. In this paper, the Canal Istanbul Project is evaluated according to basic motivations and claims of the PM, multi-perspective view through challenges and limitation that the project is likely to face with and speculations on implementation approach. The final discussion on the project is based on benefits/losses of Istanbul once the project will be implemented.
Perfluoroalkyl substances in waters along the Grand Canal, China.

Science.gov (United States)

Piao, H T; Jiao, X C; Gai, N; Chen, S; Lu, G H; Yin, X C; Yamazaki, E; Yamashita, N; Tan, K Y; Yang, Y L; Pan, J

2017-07-01

The Grand Canal, also known as the Beijing-Hangzhou Grand Canal, is a UNESCO World Heritage Site and the longest canal in the world. It is an important trunk line of the South-to-North Water Diversion Project in China. The contamination status and spatial distributions of perfluoroalky substances (PFASs) in waters of the Grand Canal were investigated. The total concentrations of PFASs (∑PFASs) range from 7.8 ng/L to 218.0 ng/L, with high ∑PFASs occurring in the southern part of the Grand Canal which is located in a highly urbanized and economically developed region. The dominance of PFOA showed a decreasing trend toward north while shorter chain homologue proportions increased in the northern part of the Canal which mainly traverses underdeveloped and rural areas in Eastern China. Positive correlations were observed between ∑PFASs and the population density as well as GDP per capita. Intersection with large rivers may affect the contamination levels and composition of PFASs in the water of the Grand Canal near the intersection sites. Copyright © 2017 Elsevier Ltd. All rights reserved.
A STUDY OF ROOT CANAL MORPHOLOGY OF Cebus apella TEETH ESTUDO ANATÔMICO DO CANAL RADICULAR DE DENTES DE Cebus apella

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Priscilla Rocha Afonso

2008-12-01

Full Text Available Realizou-se um estudo anatômico em dentes do Cebus apella, para análise da anatomia interna do canal radicular dessa espécie, normatizando seu uso como modelo experimental. Utilizaram-se doze animais adultos. Após a remoção do tecido orgânico, os dentes foram removidos, seccionados e fotografados, sendo analisados com um estereomicroscópio. Os resultados mostraram que os dentes apresentaram características semelhantes às dos seres humanos, mas com algumas peculiaridades, tais como: a anatomia do canal radicular variou de oval para circular; nos caninos inferiores, os canais são semelhantes a um rim, o que reflete o contorno externo da raiz; nos molares superiores, os canais mesiobucal e distobucal são ovais, seguindo o contorno geral do dente. Os autores concluem que esta espécie pode ser utilizada como modelo em pesquisas odontológicas, principalmente em estudos do tratamento do sistema de canal radicular.

PALAVRAS-CHAVES: Anatomia, dentes, Cebus apella. An anatomic study of Cebus apella root teeth was performed to analyze the internal anatomy of permanent dentition, normalizing its use as experimental model endodontic research. Twelve adult animals were used in this study. After the removal of the organic tissue, the all teeth were removed, sectioned, analyzed and photographed with a stereomicroscope. The results showed that the anatomy of root canal of this species are similar to human dental anatomy, considering the shape, pathway and number of canals, but with some peculiarities, such as: the root canal anatomy varied from oval to circular; in the lower canines, the canals are resembled a kidney, reflecting the outside contour of the root; in the upper molars, the mesiobuccal and distobuccal canals are oval, following the general contour of the tooth. The authors conclude that this primate can be applied as models for study of root canal treatment in human beings, in special the upper central and lateral incisors
Computed tomography in lumbar canal stenosis

International Nuclear Information System (INIS)

Ohta, Shu; Baba, Itsushi; Ishida, Akihisa; Sumida, Tadayuki; Sasaki, Seishu

1984-01-01

Preoperative CT was done in 39 patients with lumbar canal stenosis. Marked symmetrical narrowing of the whole vertebral canal was seen in the group with nervous symptoms in the cauda equina. Deformed bilateral intervertebral joints were seen in the group with both nervous symptoms in the cauda equina and radicular sciatica. The lateral recess on the affected side was markedly narrowed by the projection of the upper and lower joints and herniation. In the group with radicular sciatica, the vertebral canal itself was not so narrowed, but the unilateral intervertebral joint was extremely deformed, causing a narrowing of the lateral recess. There were large differences in the angle of the left and right intervertebral joints. (Namekawa, K)
Alien invasions and the game of hide and seek in Patagonia.

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Martin Lindegren

Full Text Available The introduction, establishment and spread of alien species is a major threat to biodiversity and the provision of ecosystem services for human wellbeing. In order to reduce further loss of biodiversity and maintain productive and sustainable ecosystems, understanding the ecological mechanisms underlying species invasions and avoiding potentially harmful effects on native communities is urgently needed, but largely lacking. We here demonstrate, by means of hydroacoustics and advanced spatial modelling, how native fish species as a result of previous exposure to native predators may successfully respond to invasive novel predators through a complicated game of hide and seek, minimizing spatio-temporal overlap with predators, and potentially facilitating coexistence between native prey species (Galaxiids and introduced novel predators (Salmonids in a deep Andean lake, Patagonia.
Canal switch after canalith repositioning procedure for benign paroxysmal positional vertigo.

Science.gov (United States)

Lin, Giant C; Basura, Gregory J; Wong, Hiu Tung; Heidenreich, Katherine D

2012-09-01

Canal switch is a complication following canalith repositioning procedure (CRP) for posterior canal benign paroxysmal positional vertigo (BPPV). Instead of being returned to the utricle, the loose otoconia migrate into the superior or horizontal semicircular canal. Patients remain symptomatic, and treatment can be ineffective unless the switch is recognized and additional repositioning maneuvers directed toward the appropriate semicircular canal are performed. This report provides the first videographic documentation of canal switch involving conversion of unilateral posterior semicircular canal BPPV to geotropic horizontal canalithiasis. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.
Respuesta dietaria de tres rapaces frente a una presa introducida en Patagonia Dietary response of three raptor species to an introduced prey in Patagonia

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ANA L. MONSERRAT

2005-09-01

Full Text Available Los depredadores de marcada respuesta funcional pueden poseer la capacidad de estabilizar las poblaciones de sus presas, lo cual es destacable en el caso de presas introducidas, que suelen causar impactos negativos en los ecosistemas nativos y las actividades agropecuarias. La situación actual de la Patagonia es crítica respecto a la introducción de especies. Estudios previos indican que los depredadores nativos exhiben un cambio general en sus dietas debido a la introducción de presas exóticas que están reemplazando a sus presas originales. Determinamos los hábitos alimenticios del águila (Geranoaetus melanoluecus, el búho magallánico (Bubo magellanicus y el aguilucho común (Buteo polyosoma, tres de las principales aves depredadoras de la liebre europea (Lepus europaeus, introducida en el noroeste de Patagonia. Para esto analizamos 321, 115 y 78 egagrópilas de águila, búho y aguilucho respectivamente. Evaluamos las respuestas funcionales a la densidad de liebre europea y comparamos las dietas entre sitios diferentes. Las principales presas del aguilucho y del búho fueron los roedores sigmodontinos y en segundo lugar los tuco-tucos (Ctenomys spp.. El águila consumió principalmente liebres y en segundo lugar tuco-tucos, presentando una respuesta funcional significativa para la presa introducida. La dieta de este rapaz fue diferente entre sitios con alta y baja densidad de liebres. Para los otros dos rapaces no encontramos una respuesta funcional significativa para la liebre europea, pero la dieta del aguilucho varió en función del sitio geográfico. Concluimos que tanto el águila mora como el aguilucho se alimentan de manera generalista, siendo el búho el único de los tres rapaces con tendencia especialista sobre pequeños roedores. Por otra parte, la variación de la dieta del águila en función de la densidad de liebre europea le brinda el potencial de contribuir a la regulación de las poblaciones de la misma
C-shaped root canal in a maxillary first molar: a case report.

Science.gov (United States)

Yilmaz, Z; Tuncel, B; Serper, A; Calt, S

2006-02-01

This case report presents an unusual C-shaped root canal system in a maxillary first molar tooth. Although C-shaped root canals are most frequently seen in the mandibular second molar, they may also appear in maxillary molars. A literature search revealed only a few case reports of C-shaped root canal systems in maxillary molars. The present case describes a C-shaped canal in the buccal root of a maxillary first molar. The endodontic access cavity displayed two canal orifices, one leading to the canal system in the buccal root, the other into the palatal root canal system. In the buccal root, what appeared to be the mesial and distal canals joined to form a single C-shaped canal. --Careful examination of radiographs and the internal anatomy of teeth is essential.-- The location and morphology of root canals should be identified at high magnification under the microscope.
Comparison among manual instruments and PathFile and Mtwo rotary instruments to create a glide path in the root canal preparation of curved canals.

Science.gov (United States)

Alves, Vanessa de Oliveira; Bueno, Carlos Eduardo da Silveira; Cunha, Rodrigo Sanches; Pinheiro, Sérgio Luiz; Fontana, Carlos Eduardo; de Martin, Alexandre Sigrist

2012-01-01

Nickel-titanium rotary instruments reduce procedural errors and the time required to finish root canal preparation. The goal of this study was to evaluate the occurrences of apical transportation and canal aberrations produced with different instruments used to create a glide path in the preparation of curved root canals, namely manual K-files (Dentsply Maillefer, Ballaigues, Switzerland) and PathFile (Dentsply Maillefer) and Mtwo (Sweden and Martina, Padua, Italy) nickel-titanium rotary files. The mesial canals of 45 mandibular first and second molars (with curvature angles between 25° and 35°) were selected for this study. The specimens were divided randomly into 3 groups with 15 canals each, and canal preparation was performed by an endodontist using #10-15-20 K-type stainless steel manual files (group M), #13-16-19 PathFile rotary instruments (group PF), and #10-15-20 Mtwo rotary instruments (group MT). The double digital radiograph technique was used, pre- and postinstrumentation, to assess whether apical transportation and/or aberration in root canal morphology occurred. The initial and final images of the central axis of the canals were compared by superimposition through computerized analysis and with the aid of magnification. The specimens were analyzed by 3 evaluators, whose calibration was checked using the Kendall agreement test. No apical transportation or aberration in root canal morphology occurred in any of the teeth; therefore, no statistical analysis was conducted. Neither the manual instruments nor the PathFile or Mtwo rotary instruments used to create a glide path had any influence on the occurrence of apical transportation or produced any canal aberration. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Fractional-order mathematical model of an irrigation main canal pool

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Shlomi N. Calderon-Valdez

2015-09-01

Full Text Available In this paper a fractional order model for an irrigation main canal is proposed. It is based on the experiments developed in a laboratory prototype of a hydraulic canal and the application of a direct system identification methodology. The hydraulic processes that take place in this canal are equivalent to those that occur in real main irrigation canals and the results obtained here can therefore be easily extended to real canals. The accuracy of the proposed fractional order model is compared by deriving two other integer-order models of the canal of a complexity similar to that proposed here. The parameters of these three mathematical models have been identified by minimizing the Integral Square Error (ISE performance index existing between the models and the real-time experimental data obtained from the canal prototype. A comparison of the performances of these three models shows that the fractional-order model has the lowest error and therefore the higher accuracy. Experiments showed that our model outperformed the accuracy of the integer-order models by about 25%, which is a significant improvement as regards to capturing the canal dynamics.
Cultural Transmission of Traditional Knowledge in two populations of North-western Patagonia

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Lozada Mariana

2008-12-01

Full Text Available Abstract Background In the present study we have investigated the cultural transmission of two types of traditional plant knowledge in two communities of North-western Patagonia, Argentina. In the Pilcaniyeu community, we studied the transmission of traditional knowledge related to horticultural practices in home-gardens, greenhouses and gardens; while in the community of Cuyin Manzano, we studied wild plant gathering customs. Methods Ethnobotanical fieldwork was conducted by means of semi-structured interviews, in which we investigated which plants are used, at what life history phase was learned, modes of transmission and who the principal transmitters were in childhood and adulthood. In both communities, each of this three aspects related to cultural transmission were categorized and the frequencies of each category were obtained. The total number of species recorded in each community was also calculated. Frequencies were analyzed with the Chi-square test of independence. Results and discussion In both communities, transmission of traditional plant knowledge begins at an early age, as a family custom, in which women play a predominant role. Wild plant use and horticultural knowledge continue to be learned during adulthood. This was particularly registered associated with horticultural learning, which receives greater influence from extension agents who are introducing new practices and technology. This outside influence, which implies novelty, could imply syncretism but also traditional knowledge loss. Conclusion Given the remarkable acculturation processes occurring at present in rural communities of Northwestern Patagonia, it might be of vital importance to document traditional knowledge of ancient practices. Moreover, it could be interesting to share our results with both populations in order to encourage participatory activities within the communities which could enhance traditional knowledge horizontal transmission, particularly among
Radiographic evaluation of the course and visibility of the mandibular canal

International Nuclear Information System (INIS)

Jung, Yun Hoa; Cho, Bong Hae

2014-01-01

This study was performed to investigate the course of the mandibular canal on panoramic radiography and the visibility of this canal on both panoramic radiography and cone-beam computed tomography (CBCT). The study consisted of panoramic radiographs and CBCT images from 262 patients. The course of the mandibular canal, as seen in panoramic radiographs, was classified into four types: linear, elliptical, spoon-shaped, and turning curves. The visibility of this canal from the first to the third molar region was evaluated by visually determining whether the mandibular canal was clearly visible, probably visible, or invisible. The visibility of the canal on panoramic radiographs was compared with that on CBCT images. Elliptical curves were most frequently observed along the course of the mandibular canal. The percentage of clearly visible mandibular canals was the highest among the spoon-shaped curves and the lowest among the linear curves. On panoramic radiographs, invisible mandibular canals were found in 22.7% of the examined sites in the first molar region, 11.8% in the second molar region, and 1.3% in the third molar region. On CBCT cross-sectional images, the mandibular canal was invisible in 8.2% of the examined sites in the first molar region, 5.7% in the second molar region, and 0.2% in the third molar region. The visibility of this canal was lower in the first molar region than in the third molar region. The mandibular canal presented better visibility on CBCT images than on panoramic radiographs.
About ecological aspects of "Eurasia" canal construction

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G. M. Abdurakhmanov

2010-01-01

Full Text Available Ecological aspects of "Eurasia" canal construction are considered here. The fact that can negatively affect natural area preservation (preserves, reserves, located in Kumo-Manych depression, along where the canal construction will take place, is shown in this article.
Discharge Estimation in a Lined Canal Using Information Entropy

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Yen-Chang Chen

2014-03-01

Full Text Available This study applies a new method and technology to measure the discharge in a lined canal in Taiwan. An Acoustic Digital Current Meter mounted on a measurement platform is used to measure the velocities over the full cross-section for establishing the measurement method. The proposed method primarily employs Chiu’s Equation which is based on entropy to establish a constant ratio the relation between the maximum and mean velocities in an irrigation canal, and compute the maximum velocity by the observed velocity profile. In consequence, the mean velocity of the lined canal can be rapidly determined by the maximum velocity and the constant ratio. The cross-sectional area of the artificial irrigation canal can be calculated for the water stage. Finally, the discharge in the lined canal can be efficiently determined by the estimated mean velocity and the cross-sectional area. Using the data of discharges and stages collected in the Wan-Dan Canal, the correlation of stage and discharge is also developed for remote real-time monitoring and estimating discharge from the pumping station. Overall, Chiu’s Equation is demonstrated to reliably and accurately measure discharge in a lined canal, and can serve as reference for future calibration for a stage-discharge rating curve.
Otolith and canal reflexes in human standing

Science.gov (United States)

Cathers, Ian; Day, Brian L; Fitzpatrick, Richard C

2005-01-01

We used galvanic vestibular stimulation (GVS) to identify human balance reflexes of the semicircular canals and otolith organs. The experiment used a model of vestibular signals arising from GVS modulation of the net signal from vestibular afferents. With the head upright, the model predicts that the GVS-evoked canal signal indicates lateral head rotation while the otolith signal indicates lateral tilt or acceleration. Both signify body sway transverse to the head. With the head bent forward, the model predicts that the canal signal indicates body spin about a vertical axis but the otolith signal still signifies lateral body motion. Thus, we compared electromyograms (EMG) in the leg muscles and body sway evoked by GVS when subjects stood with the head upright or bent forward. With the head upright, GVS evoked a large sway in the direction of the anodal electrode. This response was abolished with the head bent forward leaving only small, oppositely directed, transient responses at the start and end of the stimulus. With the head upright, GVS evoked short-latency (60–70 ms), followed by medium-latency (120 ms) EMG responses, of opposite polarity. Bending the head forward abolished the medium-latency but preserved the short-latency response. This is compatible with GVS evoking separate otolithic and canal reflexes, indicating that balance is controlled by independent canal and otolith reflexes, probably through different pathways. We propose that the short-latency reflex and small transient sway are driven by the otolith organs and the medium-latency response and the large sway are driven by the semicircular canals. PMID:15618274
ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

OpenAIRE

Aniketh; Mohamed; Geeta; Nandakishore; Gourav Kumar; Patrick Timothy; Jayson Mathew; Sahle Abdul

2015-01-01

Root canal irrigation is not much emphasised in endodontic therapy. Most articles discussed are on root canal shaping and obturation not much emphasis is given for irrigation. There are many irrigation solutions which are introduced into market. The primary objective of root canal therapy is the ret ention of the pulpless or pulpally involved tooth with its associated periapical tissues in a healthy state. Achievement of this objective requires that the pulpal spaces and con...
Maxillary second molar with four roots and five canals

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Xinjia Sha

2018-06-01

Full Text Available In this case report, we present a maxillary second molar variant, which had two palatal roots with two canals and two buccal roots with three canals, including a second mesiobuccal canal. A 44-year-old female patient complained about a tooth crown fracture and severe pain in her right maxillary second molar. A clinical intraoral inspection and radiography were carried out on the tooth, and a diagnosis of chronic apical periodontitis was made. Four roots (two buccal and two palatal and five canals (three buccal and two palatal were found. The anatomical variation of the tooth was further confirmed by cone-beam computed tomography, a cone-fit procedure, and a radiograph with a shifted projection angle. Root-canal treatment was performed under an endodontic microscope.
Rehabilitación de la Patagonia. Un territorio periférico escrito por la narrativa argentina actual

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Alejandro Gasel

2011-06-01

Full Text Available La comunicación consiste en la exposición de las formas de la inscripción de la Patagonia Austral en la contemporaneidad de la narrativa argentina. Puntualmente pensando dos novelas: Falsa Calma de Sonia Cristoff (2004 y La Siberia de Cristina Siscar (2006 trataremos de razonar qué sigue de vigente y qué aparece como una rehabilitación de este territorio en el proceso de producción narrativa. En este sentido, pensamos que podemos plantear no solamente el fenómeno de la representación actual de este territorio sino la productividad reconocida en los textos a partir de un juego intertextual, que sincretiza a una memoria precedente que ha descripto y inscripto el territorio con la necesidad de referencia la crisis del presente o actualidad del territorio en formas de umbralidad. Para dar cuenta de este proceso hemos de remitirnos a pensar la enunciación de los textos, los usos de géneros discursivos, en especial, el relato viaje y la implicancia de la historia y la memoria para referirse políticamente a la Patagonia Austral argentina que sigue siendo tematizado en el variopinto paisaje de la Literatura Argentina.
Root canal treatment and special needs patients.

Science.gov (United States)

Yap, E; Parashos, P; Borromeo, G L

2015-04-01

To identify current trends of root canal treatment for patients with special needs. A postal questionnaire was sent to General Dentists in Victoria, Australia and Endodontists and Special Needs Dentists across Australia to determine the extent of root canal treatment performed on special needs patients. Over a four-month period, 1120 questionnaires were distributed with an overall response rate of 63.9% (n = 716). Response rates were 63.2% (n = 655), 68.5% (n = 50) and 100.0% (n = 11) amongst General Dentists, Endodontists and Special Needs Dentists, respectively. Endodontists (95.7%) and Special Needs Dentists (100.0%) performed significantly more root canal treatment on adult patients with special needs compared with 51.2% of General Dentists, (P special needs patients compared with only 29.7% of General Dentists (P special needs patients was more likely to be carried out by specialist dental practitioners who were more likely to utilize a pharmacological approach for behaviour guidance and to perform single-visit root canal treatment compared with General Dentists. A multidisciplinary approach for special needs patients who require root canal treatment provides an opportunity for these patients to retain their dentition. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.
A promising location in Patagonia for paleoclimate and paleoenvironmental reconstructions revealed by shallow firn core from Monte San Valentin (Northern patagonia Icefield, Chile)

DEFF Research Database (Denmark)

Vimeux, F.; de Angelis, M.; Ginot, P.

2008-01-01

temperature is -11.9°C at 10-m depth allowing to expect well preserved both chemical and isotopic signals, unperturbed by water percolation. The dating of the core, on the basis of a multi-proxy approach combining annual layer counting and radionuclide measurements, shows that past environment and climate can......The study of past climate variability from ice core investigations has been largely developed both in polar areas over the past decades and, more recently, in tropical regions, specifically along the South American Andes between 0° and 20°S. However a large gap still remains at mid......-latitudes in the Southern Hemisphere. In this framework, a 15.3-m long shallow firn core has been extracted in March 2005 from the summit plateau of Monte San Valentín (3747 m, 46°35'S, 73°19'W) in the Northern Patagonia Icefield to test its potential for paleoclimate and paleoenvironmental reconstructions. The firn...

An endodontic management of mandibular third molar with five root canals

OpenAIRE

Dakshita Joy Sinha; Ashish Amit Sinha

2014-01-01

The existence of several anatomical variations in the root canal system may contribute to failure of the root canal therapy. The planning and performing of endodontic therapy requires knowledge of the internal dental morphology. This paper reports the case of a left mandibular third molar that presented with five root canals; a case of unusual root canal morphology so as to demonstrate the anatomic variations in mandibular third molars. Root canal therapy and case management are described. Th...
The Effect of Canal Contamination with Saliva on Apical Sealing

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S Sabaghi

2014-08-01

Full Text Available Introduction: Root canal obturation aims at sealing the root canal system to prevent re-contamination of canal and periapical space. Presence of moisture in canal before obturation may posit a negative effect on the quality of canal sealing. Therefore, this study was conducted to investigate the effect of canal contamination with saliva on apical microleakage. Methods: In this laboratory study, 58 human uni-root teeth were cleaned and shaped for obturation with gutta percha and sealer AH26. In the case group, specimens were contaminated with human saliva immediately before obturation, whereas the teeth in the control group were kept dry. All canals were filled by lateral condensation technique. Moreover, the teeth were placed in methylene blue dye for 3 days. Dye penetration was measured using a stereomicrosope. As a matter of fact, the study data were analyzed via utilizing t-test. Results: A significant difference was found between the two groups in regard with the apical leakage(P<0.001. The microleakage mean of dye in the dry group was 3/48mm, whereas it was 6/36mm in the saliva contaminated group. Conclusion: The study findings revealed that complete drying of canal can improve apical sealing.
An endodontic management of mandibular third molar with five root canals

Directory of Open Access Journals (Sweden)

Dakshita Joy Sinha

2014-01-01

Full Text Available The existence of several anatomical variations in the root canal system may contribute to failure of the root canal therapy. The planning and performing of endodontic therapy requires knowledge of the internal dental morphology. This paper reports the case of a left mandibular third molar that presented with five root canals; a case of unusual root canal morphology so as to demonstrate the anatomic variations in mandibular third molars. Root canal therapy and case management are described. This report highlights the importance of looking for additional roots and root canals so as to enable clinicians to treat a case successfully, which might have ended in failure.
Optimizing the chemical aspect of root canal irrigation

OpenAIRE

de Macedo, R.G.

2013-01-01

Root canal treatment is aimed at the removal of inflamed and infected tissue present in the root canal system. It will prevent the entrance of new microorganisms or nutrients in order to maintain or create a healthy environment around the root. There is sufficient evidence that shows that traditional endodontic therapy cannot make the root canal system completely free of bacteria. Moreover, it may not always result in complete healing of apical periodontitis, highlighting the need of optimizi...
Magnetic resonance imaging of the internal auditory canal

International Nuclear Information System (INIS)

Daniels, D.L.; Herfkins, R.; Koehler, P.R.; Millen, S.J.; Shaffer, K.A.; Williams, A.L.; Haughton, V.M.

1984-01-01

Three patients with exclusively or predominantly intracanalicular neuromas and 5 with presumably normal internal auditory canals were examined with prototype 1.4- or 1.5-tesla magnetic resonance (MR) scanners. MR images showed the 7th and 8th cranial nerves in the internal auditory canal. The intracanalicular neuromas had larger diameter and slightly greater signal strength than the nerves. Early results suggest that minimal enlargement of the nerves can be detected even in the internal auditory canal
Quantifying canal leakage rates using a mass-balance approach and heat-based hydraulic conductivity estimates in selected irrigation canals, western Nebraska, 2007 through 2009

Science.gov (United States)

Hobza, Christopher M.; Andersen, Michael J.

2010-01-01

The water supply in areas of the North Platte River Basin in the Nebraska Panhandle has been designated as fully appropriated or overappropriated by the Nebraska Department of Natural Resources (NDNR). Enacted legislation (Legislative Bill 962) requires the North Platte Natural Resources District (NPNRD) and the NDNR to develop an Integrated Management Plan (IMP) to balance groundwater and surface-water supply and demand in the NPNRD. A clear understanding of the groundwater and surface-water systems is critical for the development of a successful IMP. The primary source of groundwater recharge in parts of the NPNRD is from irrigation canal leakage. Because canal leakage constitutes a large part of the hydrologic budget, spatially distributing canal leakage to the groundwater system is important to any management strategy. Surface geophysical data collected along selected reaches of irrigation canals has allowed for the spatial distribution of leakage on a relative basis; however, the actual magnitude of leakage remains poorly defined. To address this need, the U.S. Geological Survey, in cooperation with the NPNRD, established streamflow-gaging stations at upstream and downstream ends from two selected canal reaches to allow a mass-balance approach to be used to calculate daily leakage rates. Water-level and sediment temperature data were collected and simulated at three temperature monitoring sites to allow the use of heat as a tracer to estimate the hydraulic conductivity of canal bed sediment. Canal-leakage rates were estimated by applying Darcy's Law to modeled vertical hydraulic conductivity and either the estimated or measured hydraulic gradient. This approach will improve the understanding of the spatial and temporal variability of canal leakage in varying geologic settings identified in capacitively coupled resistivity surveys. The high-leakage potential study reach of the Tri-State Canal had two streamflow-gaging stations and two temperature monitoring
Maxillary First Molars with 2 Distobuccal Canals: A Case Series.

Science.gov (United States)

Fogel, Howard M; Cunha, Rodrigo Sanches

2017-11-01

An appreciation of the anatomic complexity of the root canal system is essential at every step of endodontic treatment. Endodontic treatment of teeth with unusual root canal anatomy presents a unique challenge. Eight patients underwent nonsurgical root canal treatment of 3-rooted maxillary first molars in a specialty endodontic private practice. Four cases of Weine type II and 4 cases of Weine type III canal configurations in the distobuccal root of maxillary first molars were presented.This article highlighted an uncommon anatomic variation of 2 canals in the distobuccal root of the maxillary first molar. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804) (Dasypodidae) from northern Patagonia, Argentina

OpenAIRE

Squarcia, SM.; Sidorkewicj, NS.; Camina, R.; Casanave, EB.

2009-01-01

The aim of this study was to study the sexual dimorphism in adult Chaetophractus villosus (Desmarest, 1804), from northern Patagonia, Argentina. Eight mandibular traits were measured in 37 males and 34 females. Univariate and multivariate morphometric analysis were applied to the data set. Results showed that C. villosus was sexually dimorphic, with higher absolute values corresponding to females. The total length of the mandible was the most important variable to discriminate sexes, followed...
Assessment of bifid and trified mandicular canals using cone beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Rashsyren, Oyuntugs [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Mongolian National University Medical Science, Ulaanbaatar (United States); Choi, Jin Woo; Han, Won Jeong; Kim Eun Kyung [Dept. of Oral and Maxillofacial Radiology, Dankook University College of Dentistry, Cheonan (Korea, Republic of)

2014-09-15

To investigate the prevalence of bifid and trifid mandibular canals using cone-beam computed tomography (CBCT) images, and to measure their length, diameter, and angle. CBCT images of 500 patients, involving 755 hemi-mandibles, were used for this study. The presence and type of bifid mandibular canal was evaluated according to a modified classification of Naitoh et al. Prevalence rates were determined according to age group, gender, and type. Further, their diameter, length, and angles were measured using PACSPLUS Viewer and ImageJ 1.46r. Statistical analysis with chi-squared and analysis of variance (ANOVA) tests was performed. Bifid and trifid mandibular canals were found in 22.6% of the 500 patients and 16.2% of the 755 sides. There was no significant difference between genders and among age groups. The retromolar canal type accounted for 71.3% of the identified canals; the dental canal type, 18.8%; the forward canal type, 4.1%; and the trifid canal type, 5.8%. Interestingly, seven cases of the trifid canal type, which has been rarely reported, were observed. The mean diameter of the bifid and trifid mandibular canals was 2.2 mm and that of the main mandibular canal was 4.3 mm. Their mean length was 16.9 mm; the mean superior angle was 149.2 degrees, and the mean inferior angle was 37.7 degrees. Bifid and trifid mandibular canals in the Korean population were observed at a relatively high rate through a CBCT evaluation, and the most common type was the retromolar canal. CBCT is suggested for a detailed evaluation of bifid and trifid mandibular canals before mandibular surgery.
A study of incisive canal using a cone beam computed tomography

International Nuclear Information System (INIS)

Kim, Gyu Tae; Hwang, Eui Hwan; Lee, Sang Rae

2004-01-01

To investigate the anatomical structure of the incisive canal radiographically by a cone beam computed tomography. 38 persons (male 26, female 12) were chosen to take images of maxillary anterior region in dental CT mode using a cone beam computed tomography. The tube voltage were 65, 67, and 70 kVp, the tube current was 7 mA, and the exposure time was 13.3 seconds. The FH plane of each person was parallel to the floor. The images were analysed on the CRT display. The mean length of incisive canal was 15.87 mm ± 2.92. The mean diameter at the side of palate and nasal fossa were 3.49 mm ± 0.76 and 3.89 mm ± 1.06, respectively. In the cross-sectional shape of incisive canal, 50% were round, 34.2% were ovoid, and 15.8% were lobulated. 87% of incisive canal at the side of nasal fossa have one canal, 10.4% have two canals, and 2.6% have three canals, but these canals were merged into one canal in the middle portion of palate. The mean angles of the long axis of incisive canal and central incisor to the FH plane were 110.3 ± 6.96 and 117.45 ± 7.41, respectively. The angles of the long axis of incisive canal and central incisor to the FH plane were least correlated (r 0.258). This experiment suggests that a cone beam computed radiography will be helpful in surgery or implantation on the maxillary incisive area.
A study of incisive canal using a cone beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Kim, Gyu Tae; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

2004-03-15

To investigate the anatomical structure of the incisive canal radiographically by a cone beam computed tomography. 38 persons (male 26, female 12) were chosen to take images of maxillary anterior region in dental CT mode using a cone beam computed tomography. The tube voltage were 65, 67, and 70 kVp, the tube current was 7 mA, and the exposure time was 13.3 seconds. The FH plane of each person was parallel to the floor. The images were analysed on the CRT display. The mean length of incisive canal was 15.87 mm {+-} 2.92. The mean diameter at the side of palate and nasal fossa were 3.49 mm {+-} 0.76 and 3.89 mm {+-} 1.06, respectively. In the cross-sectional shape of incisive canal, 50% were round, 34.2% were ovoid, and 15.8% were lobulated. 87% of incisive canal at the side of nasal fossa have one canal, 10.4% have two canals, and 2.6% have three canals, but these canals were merged into one canal in the middle portion of palate. The mean angles of the long axis of incisive canal and central incisor to the FH plane were 110.3 {+-} 6.96 and 117.45 {+-} 7.41, respectively. The angles of the long axis of incisive canal and central incisor to the FH plane were least correlated (r 0.258). This experiment suggests that a cone beam computed radiography will be helpful in surgery or implantation on the maxillary incisive area.
Bilateral duplication of the internal auditory canal

International Nuclear Information System (INIS)

Weon, Young Cheol; Kim, Jae Hyoung; Choi, Sung Kyu; Koo, Ja-Won

2007-01-01

Duplication of the internal auditory canal is an extremely rare temporal bone anomaly that is believed to result from aplasia or hypoplasia of the vestibulocochlear nerve. We report bilateral duplication of the internal auditory canal in a 28-month-old boy with developmental delay and sensorineural hearing loss. (orig.)
33 CFR 117.769 - Black Rock Canal.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...
Laser scanning dental probe for endodontic root canal treatment

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Blank, Molly A. B.; Friedrich, Michal; Hamilton, Jeffrey D.; Lee, Peggy; Berg, Joel; Seibel, Eric J.

2011-03-01

Complications that arise during endodontic procedures pose serious threats to the long-term integrity and health of the tooth. Potential complexities of root canals include residual pulpal tissue, cracks, mesial-buccal 2 and accessory canals. In the case of a failed root canal, a successful apicoectomy can be jeopardized by isthmuses, accessory canals, and root microfracture. Confirming diagnosis using a small imaging probe would allow proper treatment and prevent retreatment of endodontic procedures. An ultrathin and flexible laser scanning endoscope of 1.2 to 1.6mm outer diameter was used in vitro to image extracted teeth with varied root configurations. Teeth were opened using a conventional bur and high speed drill. Imaging within the opened access cavity clarified the location of the roots where canal filing would initiate. Although radiographs are commonly used to determine the root canal size, position, and shape, the limited 2D image perspective leaves ambiguity that could be clarified if used in conjunction with a direct visual imaging tool. Direct visualization may avoid difficulties in locating the root canal and reduce the number of radiographs needed. A transillumination imaging device with the separated illumination and light collection functions rendered cracks visible in the prepared teeth that were otherwise indiscernible using reflected visible light. Our work demonstrates that a small diameter endoscope with high spatial resolution may significantly increase the efficiency and success of endodontic procedures.
Radiographic versus electronic root canal working length determination

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Lumnije Kqiku

2011-01-01

Conclusions: The present ex vivo study showed that electronic root canal working length determination is not superior to radiographic methods. Both methods provided a good performance in determining the root canal working length.
46 CFR 69.7 - Vessels transiting the Panama and Suez Canals.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Vessels transiting the Panama and Suez Canals. 69.7... MEASUREMENT OF VESSELS MEASUREMENT OF VESSELS General § 69.7 Vessels transiting the Panama and Suez Canals. (a... Canal must be measured and certificated under the Arab Republic of Egypt Suez Canal Authority Rules of...
Evaluation of root canal morphology of human mandibular incisors in Yazd

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Tabrizi-zadeh M. Assistant Professor

2003-06-01

Full Text Available Statement of Problem: The main objective of endodontic therapy is chemomechanical cleansing of entire pulp cavity and its complete obturation with an inert material. During this procedure, the failure of detection and inadequate cleaning of a canal will result in failed endodontic therapy. Therefore, the dentist must have enough knowledge of root canal morphology to treat a tooth successfully."nAim: The aim of this study was to determine the number and type of root canals of mandibular incisor teeth."nMaterials and Methods: In order to do this in-vitro, descriptive study, 68 non-carious mandibular incisor teethj collected from different clinics in Yazd, were immersed in indian ink, decalcified and cleared."nResults: It was found that 55.9% of the teeth had two separate canals that in 5.5% of them, the canals"nmerged before' apical foramen. In 4.4% of these samples, two separate canals existed along the whole"nroot."nConclusion: Considering high percentage of two canals in lower mandibular incisors, during access preparation, more attempts in detection of the second canal, is emphasized.
Prevalence of the middle mesial canal in non surgical root canal treated mandibular first and second molars in a local military population

Science.gov (United States)

2016-06-13

or second mandibular molar), sex, and age. Materials and Methods Approximately 7, 000 dental records in paper chart format were reviewed at a...Army Post Graduate Dental School Douglas D. Lancaster, COL, DC 3 August 2016 Prevalence of the middle mesial canal in non-surgical root canal...Methods: 7000 dental records were reviewed for non-surgical root canals performed from October 1970 to October 2015. The data collected included
Effects of canal enlargement and irrigation needle depth on the cleaning of the root canal system at 3 mm from the apex

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Ho-Jin Moon

2012-02-01

Full Text Available Objectives The aim of this study was to test the hypothesis, that the effectiveness of irrigation in removing smear layer in the apical third of root canal system is dependent on the depth of placement of the irrigation needle into the root canal and the enlargement size of the canal. Materials and Methods Eighty sound human lower incisors were divided into eight groups according to the enlargement size (#25, #30, #35 and #40 and the needle penetration depth (3 mm from working length, WL-3 mm and 9 mm from working length, WL-9 mm. Each canal was enlarged to working length with Profile.06 Rotary Ni-Ti files and irrigated with 5.25% NaOCl. Then, each canal received a final irrigation with 3 mL of 3% EDTA for 4 min, followed by 5 mL of 5.25% NaOCl at different level (WL-3 mm and WL-9 mm from working length. Each specimen was prepared for the scanning electron microscope (SEM. Photographs of the 3mm area from the apical constriction of each canal with a magnification of ×250, ×500, ×1,000, ×2,500 were taken for the final evaluation. Results Removal of smear layer in WL-3 mm group showed a significantly different effect when the canal was enlarged to larger than #30. There was a significant difference in removing apical smear layer between the needle penetration depth of WL-3 mm and WL-9 mm. Conclusions Removal of smear layer from the apical portion of root canals was effectively accomplished with apical instrumentation to #35/40 06 taper file and 3 mm needle penetration from the working length.
C-SHAPED CONFIGURATION OF THE ROOT CANAL SYSTEM – PROBLEMS AND SOLUTIONS.

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Janet Kirilova

2014-06-01

Full Text Available Introduction: The patients with C-shaped configuration of the root canal system are definitely a problem in the everyday dental practice. The C-shaped configuration of the root canal can be seen in the mandibular and maxillary molars. The treatment of these teeth is very difficult. Purpose: To trace the treatment of clinical cases with C-shaped configuration of the root canal system. Material and methods: There are some different cases that are described with a C-shaped configuration of the root canal system with one, two, three and four separate root canals. Careful exploration of the floor of the pulp chamber, inspection with magnification, use of ultrasonic irrigation and a modified filling technique are of particular use. Results and Discussion: Clinical cases of a C-shaped pulp chamber and root canal system shows that this root canal aberration occurs in a wide variety and variability with a single root canal up to two, three and four separate root canals. The diameter of the root canal themselves also varies from very wide to such with a small diameter. Conclusions: Knowledge of the different anatomical variations will improve the endododntic practice of the general dental practitioners.

Revisión de la distribución de Hyalella Smith, 1874 (Crustacea, Amphipoda) en la Patagonia e islas adyacentes Revision of the distribution of Hyalella Smith, 1874 (Crustacea, Amphipoda) in Patagonia and adjacent islands

OpenAIRE

Patricio De los Ríos-Escalante; Andrés Mansilla; Christopher B Anderson

2012-01-01

Se realiza una revisión de las especies de anfípodos del género Hyalella en aguas continentales de la Patagonia, isla Tierra del Fuego, Reserva de la Biosfera de Cabo de Hornos e islas adyacentes (38-54°S). Esta zona austral presenta numerosos tipos de ambientes acuáticos continentales como lagos, humedales y arroyos, y las principales especies en ambientes bentónicos corresponden a anfípodos del género Hyalella. La bibliografía menciona la presencia de H. costera, H. chiloensis, H. falklande...
Canal transportation and centering ability of protaper and self-adjusting file system in long oval canals: An ex-vivo cone-beam computed tomography analysis.

Science.gov (United States)

Shah, Dipali Yogesh; Wadekar, Swati Ishwara; Dadpe, Ashwini Manish; Jadhav, Ganesh Ranganath; Choudhary, Lalit Jayant; Kalra, Dheeraj Deepak

2017-01-01

The purpose of this study was to compare and evaluate the shaping ability of ProTaper (PT) and Self-Adjusting File (SAF) system using cone-beam computed tomography (CBCT) to assess their performance in oval-shaped root canals. Sixty-two mandibular premolars with single oval canals were divided into two experimental groups ( n = 31) according to the systems used: Group I - PT and Group II - SAF. Canals were evaluated before and after instrumentation using CBCT to assess centering ratio and canal transportation at three levels. Data were statistically analyzed using one-way analysis of variance, post hoc Tukey's test, and t -test. The SAF showed better centering ability and lesser canal transportation than the PT only in the buccolingual plane at 6 and 9 mm levels. The shaping ability of the PT was best in the apical third in both the planes. The SAF had statistically significant better centering and lesser canal transportation in the buccolingual as compared to the mesiodistal plane at the middle and coronal levels. The SAF produced significantly less transportation and remained centered than the PT at the middle and coronal levels in the buccolingual plane of oval canals. In the mesiodistal plane, the performance of both the systems was parallel.
Shaping ability of several nickel–titanium systems in double-curved simulated canals

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Mothanna Alrahabi

2017-06-01

Conclusion: The iRaCe, ProTaper Next, Wave One, and TF systems preserved the original shape of the double-curved (S-shaped canal with minimum root canal transportation. These systems produced satisfactory root canal instrumentation in S-shaped canals.
Report from the Panama Canal Stakeholder Working Group.

Science.gov (United States)

2013-03-01

This project assists the Texas Department of Transportation (TxDOT) in assessing the potential impacts of the Panama Canal expansion on Texas ports and the landside transportation system. TxDOT formed a Panama Canal Stakeholder Working Group (PCSWG) ...
Comparison of Curved Root Canals Prepared with Various Chelating Agents

Science.gov (United States)

2012-06-01

aqueous base (11). According to Bramante and Betti, instrumentation with NiTi hand files using EDTA caused greater deviation of the root canal from...15. Peters OA, Peters CI, Schonenberger K, Barbakow F. ProTaper rotary root canal preparation: effects of canal anatomy on final shape analysed by
A new species of Parapsectrocladius Cranston (Diptera: Chironomidae: Orthocladiinae) from Patagonia, Argentina.

Science.gov (United States)

Donato, Mariano; Mauad, Melina; Fuentes, María Cecilia

2015-01-21

Parapsectrocladius setosus sp. n. is described and figured as pupa and male imago, based on material collected in Patagonia, Argentina. The male of the new species groups with P. escondido Cranston & Añón Suárez by having the anal point tapering triangular; inferior volsella simple, rounded, without any dorsal ridge and apically blunt. It can be distinguished from P. escondido by the possession of strong setae on the inner margin of inferior volsella. New material of Parapsectrocladius belonging from several localities allows us to emend the generic diagnosis of the adult male, female and larva of Parapsectrocladius, discuss its phylogenetic position and to expand the geographic distribution of P. acuminatus Cranston, P. escondido and P. reissi. Cranston.
Morphometric study of the lumbar spinal canal in the Korean population.

Science.gov (United States)

Lee, H M; Kim, N H; Kim, H J; Chung, I H

1995-08-01

The anatomic dimensions of the vertebral body and spinal canal of the lumbar spine were analyzed in Koreans. To determine the normal dimension of the lumbar spinal canal in Koreans, to determine whether there are any racial differences in the morphometry of the lumbar spinal canal, and to provide criteria for diagnosing spinal stenosis in the Far Eastern Asian. Some radiologic and anatomic studies have been conducted regarding the size of the lumbar spinal canal of whites and blacks in western and African countries. One-thousand-eight-hundred measurements were performed on the transverse and sagittal diameters of vertebral bodies and spinal canals using complete sets of 90 lumbar vertebrae. The mean mid-sagittal diameter of the lumbar spinal canal in the Korean population was less than that measured in white and African populations, but there was no significant differences between the Korean, white, and African populations regarding the transverse diameter of the lumbar spinal canal. The mid-sagittal diameter of the lumbar spinal canal is narrowest in the Far Eastern Asian population; the radiologic criteria of spinal stenosis should be reconsidered for these people.
Root Canal Configuration of Mandibular First and Second Premolars in an Iranian Population

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Nemat Eskandarzadeh

2007-08-01

Full Text Available
Background and aims. It is critical to have a proper knowledge of the normal anatomy of the pulp and its variations for the success of endodontic treatment. The aim of this study was to determine the canal configuration and the prevalence of C-shaped canals in mandibular first and second premolars in a North-Western Iranian population.
Materials and methods. A total of 163 extracted mandibular first and 103 mandibular second premolars were injected with India ink and demineralized . They were made clear and transparent with methyl salicylate and the anatomy of their canal(s was studied.
Results. The results showed that 98% of mandibular first premolars had one root, 2% had two roots, 70.6% had one canal, 27.8% had two canals, 1.2% had three canals and the prevalence of C-shaped canals was 2.4%. All mandibular second premolars had one root, 80.5% had one canal, 17.5% had two canals and the prevalence of C-shaped canals was 2%.
Conclusion. It is important that clinicians, before treatment of mandibular first and second premolars, pay complete attention to radiographs, have a true concept of the number of root(s and canal(s, and prepare a correct access cavitiy.
Polen de las Mieles de la Patagonia Andina (Chubut-Argentina Pollen of honeys from the Andean Patagonia (Chubut-Argentina

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Alicia Forcone

2006-07-01

Full Text Available Se describen e ilustran mediante fotomicrografías tomadas con MO y MEB, 30 tipos polínicos, determinados en las mieles producidas en la región andina de Chubut (Patagonia Argentina. Los tipos morfológicos descriptos pertenecen a las siguientes familias: Alstroemeriaceae, Apiaceae, Buddlejaceae, Caryophyllaceae, Caprifoliaceae, Celastraceae, Clusiaceae, Convolvulaceae, Ericaceae, Elaeocarpaceae, Fabaceae, Fagaceae, Lamiaceae, Papaveraceae, Polemoniaceae, Polygalaceae, Proteaceae, Ranunculaceae, Rosaceae, Saxifragaceae, Solanaceae, Thymelaceae y Verbenaceae. La mayoría de los tipos polínicos descriptos fueron hallados en las mieles como polen de menor importancia o traza con excepción de Aristotelia chilensis y Escallonia sp., que alcanzaron la categoría de polen dominante, y de Lomatia hirsuta, hallada como polen secundario.Thirty pollen types identified in the honeys from the Andean region of Chubut are described and illustrated by means of LM and SEM photomicrographs. Pollen types belong to the following families: Alstroemeriaceae, Apiaceae, Buddlejaceae, Caryophyllaceae, Caprifoliaceae, Celastraceae, Clusiaceae, Convolvulaceae, Ericaceae, Elaeocarpaceae, Fabaceae, Fagaceae, Lamiaceae, Papaveraceae, Polemoniaceae, Polygalaceae, Proteaceae, Ranunculaceae, Rosaceae, Saxifragaceae, Solanaceae, Thymelaceae, and Verbenaceae. Most pollen types described were found in the honeys as minor important pollen or traces, except Aristotelia chilensis, Escallonia sp., which reached the category of dominant pollen, and Lomatia hirsuta, which was found as secondary pollen.
RETRATAMENTO ENDODÔNTICO: ESTUDO COMPARATIVO ENTRE TÉCNICA MANUAL, ULTRA-SOM E CANAL FINDER ENDODONTIC RETREATMENT: COMPARATIVE STUDY BETWEEN MANUAL TECHNIQUE, ULTRASONIC SCALER, AND CANAL FINDER

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Clovis Monteiro BRAMANTE

1998-01-01

Full Text Available Instrumentações manual, ultra-sônica e com Canal Finder foram utilizadas para retratamento de 30 dentes com canais obturados com guta-percha e óxido de zinco e eugenol. Avaliaram-se: 1. tempo gasto para a penetração inicial até o ápice; 2. tempo para completar a limpeza; 3. extrusão de material e 4. limpeza dos canais. O Canal Finder foi a técnica que propiciou melhor limpeza, seguida da manual e da ultra-sônica. A parede palatina do canal foi constantemente mais limpa do que a vestibular. Quanto à extrusão, a técnica de ultra-som foi a que propiciou mais extravasamento de material obturador.Endodontic retreatment of 30 teeth filled with guta percha and zinc oxide-eugenol was carried out using manual instrumentation, ultrasonic scaler, and the Canal Finder System. The following variables were evaluated: time spent to reach the apex; time spent to complete cleaning of the canal; apical extrusion of material; and cleanliness of the canals. Results showed the Canal Finder System as providing the highest level of cleanliness of the canal system; lingual walls were constantly cleaner than buccal walls; ultrasonic technique presented a greater degree of apical extrusion of filling material.
Computed tomography imaging for superior semicircular canal dehiscence syndrome

International Nuclear Information System (INIS)

Dobeli, Karen

2006-01-01

Superior semicircular canal dehiscence is a newly described syndrome of sound and/or pressure induced vertigo. Computed tomography (CT) imaging plays an important role in confirmation of a defect in the bone overlying the canal. A high resolution CT technique utilising 0.5 mm or thinner slices and multi-planar reconstructions parallel to the superior semicircular canal is required. Placement of a histogram over a suspected defect can assist CT diagnosis
Comparative study of 6 rotary nickel-titanium systems and hand instrumentation for root canal preparation in severely curved root canals of extracted teeth.

Science.gov (United States)

Celik, Davut; Taşdemir, Tamer; Er, Kürşat

2013-02-01

Some improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments. The mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°-40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test. NiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P ProTaper Universal rotary systems manufactured by traditional methods. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Interaction of Aquifer and River-Canal Network near Well Field.

Science.gov (United States)

Ghosh, Narayan C; Mishra, Govinda C; Sandhu, Cornelius S S; Grischek, Thomas; Singh, Vikrant V

2015-01-01

The article presents semi-analytical mathematical models to asses (1) enhancements of seepage from a canal and (2) induced flow from a partially penetrating river in an unconfined aquifer consequent to groundwater withdrawal in a well field in the vicinity of the river and canal. The nonlinear exponential relation between seepage from a canal reach and hydraulic head in the aquifer beneath the canal reach is used for quantifying seepage from the canal reach. Hantush's (1967) basic solution for water table rise due to recharge from a rectangular spreading basin in absence of pumping well is used for generating unit pulse response function coefficients for water table rise in the aquifer. Duhamel's convolution theory and method of superposition are applied to obtain water table position due to pumping and recharge from different canal reaches. Hunt's (1999) basic solution for river depletion due to constant pumping from a well in the vicinity of a partially penetrating river is used to generate unit pulse response function coefficients. Applying convolution technique and superposition, treating the recharge from canal reaches as recharge through conceptual injection wells, river depletion consequent to variable pumping and recharge is quantified. The integrated model is applied to a case study in Haridwar (India). The well field consists of 22 pumping wells located in the vicinity of a perennial river and a canal network. The river bank filtrate portion consequent to pumping is quantified. © 2014, National GroundWater Association.
Evolution of canals system linking the Vistula, Dnieper and Neman basins

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Brykala, Dariusz; Badziai, Vitali

2014-05-01

The aim of this study is to reconstruct landscape changes in the Polesie Region - one of the largest European swampy areas (Belarus), as a result of the creation and operation of a network of canals. From the 16th century efforts were undertaken to connect the Polish areas located in the drainage basins of the Black Sea and Baltic Sea with canals. Already in 1631 the Polish Sejm (parliament) approved the project to build a canal linking the River Berezina (Dnieper basin) with the River Neris (Neman basin). However, the complicated political and economic situation of the country did not allow doing this. Only in the second half of the 18th c. hetman Ogiński financed the construction of a canal linking the Dnieper and Neman basins. The canal connecting the River Szczara (Neman basin) with the River Jasiołda (Pripyat basin) was named after its creator - the Ogiński Canal. At the same time the construction of the Królewski (Royal) Canal linking the River Muchavets (Vistula basin) and the River Pina (Pripyat basin) was under way. The construction of the canal was completed in 1783. The winding channels of the Pina and Muchavets were straightened, and the numerous canals feeding the waterway system drained vast area of marshes and wetlands of the Polesia Region. The last element that connects the catchments of the Vistula and Neman is the Augustów Canal built in the years 1825-1839 (linking the catchments of the Biebrza and Neman). Numerous changes in political boundaries in the watershed area between the Black Sea and the Baltic Sea drainage basins caused the destruction of the hydraulic structures. All the analysed canals were completely destroyed during the two world wars. In the last 200 years the amount and type of locks and weirs has changed. For example, there were no weirs on the Royal Canal in the late 18th c., in the middle of the 19th c. there were 22 such structures, while now that number has gone down to 10. All canals were created for economic reasons
Effect of Instrument Design and Access Outlines on the Removal of Root Canal Obturation Materials in Oval-shaped Canals.

Science.gov (United States)

Niemi, Tuomas K; Marchesan, Melissa A; Lloyd, Adam; Seltzer, Robert J

2016-10-01

The aim of this study was to compare the effectiveness of TRUShape (TS) instruments with ProFile Vortex Blue (VB) instruments for the removal of obturation materials during retreatment of single-canal mandibular premolars performed through 2 access outlines. Initial root canal treatment was completed through a contracted endodontic cavity (CEC) design. Canals were instrumented to an F2 ProTaper instrument, obturated with warm lateral condensation of gutta-percha with AH Plus sealer, and allowed to set for 30 days at 37°C and 100% humidity. For retreatment, specimens were divided into 2 groups (n = 24) on the basis of access outline, CEC or traditional endodontic cavity (TEC). Retreatment was initiated by using ProTaper Retreatment instruments (D1-D3). Specimens were then stratified, further divided (n = 12), and reinstrumented up to TS 40 .06v or 40 .06 VB. Irrigation was performed by using 8.25% NaOCl and QMix 2in1. Retreatment time was recorded. Teeth were sectioned and photographed, and the percentage of remaining obturation materials was measured. Data were analyzed with Kruskal-Wallis analysis of variance for two-factor tests (α canal surface when compared with TEC-VB, CEC-TS, and TEC-TS (P ≤ .05). None of these other combinations were different from each other (P > .05). Significantly more time was required for retreatment with CEC-TS (27.68 ± 1.4 minutes) than the other groups (P root canal surface of mandibular premolars. However, in the presence of a CEC access design, using TS instruments removed more obturating material in single-rooted, oval-shaped canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Root canal preparation in endodontics: conventional versus laser methods

Science.gov (United States)

Goodis, Harold E.; White, Joel M.; Marshall, Sally J.; Marshall, Grayson W.; Moskowitz, Emrey

1992-06-01

Conventional cleaning and shaping of root canal systems employs hand and/or rotary instrumentation to remove the contents of the canal and shape the canal to receive a filling material. With the advent of the Nd:YAG laser system another method of accomplishing proper cleaning and shaping is evaluated. Single rooted teeth were radiographed bucco- lingually and mesio-distally and were divided into 2 groups. The first group was accessed and the root canal systems cleaned and shaped with a step back technique utilizing hand files and gates glidden burs. At completion of the procedure the teeth were again radiographed at the same positions as those prior to the procedure. The teeth were split longitudinally and examined under scanning electron microscopy to assess cleaning. The second group of teeth were accessed, and cleaning and shaping was accomplished using the Nd:YAG laser in combination with hand files and rotary instruments. These teeth were subjected to the same analysis as those in the first group. The before and after radiographs of each group were subjected to image analysis to determine effectiveness of the two methods in shaping the canal systems. We will discuss the ability of Nd:YAG to clean and shape root canal spaces and remove smear layer and organic tissue remnants from those areas.
ROUTING DEMAND CHANGES TO USERS ON THE WM LATERAL CANAL WITH SACMAN

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Most canals have either long travel times or insufficient in-canal storage to operate on-demand. Thus, most flow changes must be routed through the canal. Volume compensation has been proposed as a method for easily applying feedforward control to irrigation canals. SacMan (Software for Automated Ca...
MR determination of neonatal spinal canal depth.

Science.gov (United States)

Arthurs, Owen; Thayyil, Sudhin; Wade, Angie; Chong, W K Kling; Sebire, Neil J; Taylor, Andrew M

2012-08-01

Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth - MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI). Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age. ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r>0.8). A simple linear model MSCD (mm)=3×Weight (kg)+5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model. There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm)=3×Weight (kg)+5 could result in fewer traumatic LPs in this population. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
MR determination of neonatal spinal canal depth

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Arthurs, Owen, E-mail: owenarthurs@uk2.net [Centre for Cardiovascular MR, Great Ormond Street Hospital for Children, London WC1N 3JH (United Kingdom); Thayyil, Sudhin, E-mail: s.thayyil@ucl.ac.uk [Academic Neonatology, Institute for Women' s Health, London WC1E 6AU (United Kingdom); Wade, Angie, E-mail: a.wade@ucl.ac.uk [Centre for Paediatric Epidemiology and Biostatistics, UCL Institute of Child Health, London (United Kingdom); Chong, W.K., E-mail: Kling.Chong@gosh.nhs.uk [Paediatric Neuroradiology, Great Ormond Street Hospital for Children, London (United Kingdom); Sebire, Neil J., E-mail: Neil.Sebire@gosh.nhs.uk [Histopathology, Great Ormond Street Hospital for Children, London WC1E 6AU (United Kingdom); Taylor, Andrew M., E-mail: a.taylor76@ucl.ac.uk [Centre for Cardiovascular MR, Cardiorespiratory Unit, Great Ormond Street Hospital for Children and UCL Institute of Cardiovascular Science, London WC1E 6AU (United Kingdom)

2012-08-15

Objectives: Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth - MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI). Patients and methods: Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04 kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age. Results: ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r > 0.8). A simple linear model MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model. Conclusion: There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 could result in fewer traumatic LPs in this population.
CANAL user's manual

International Nuclear Information System (INIS)

Faya, A.; Wolf, L.; Todreas, N.

1979-11-01

CANAL is a subchannel computer program for the steady-state and transient thermal hydraulic analysis of BWR fuel rod bundles. The purpose of this manual is to introduce the user into the mechanism of running the code by providing information about the input data and options

Rehabilitación de la Patagonia. Un territorio periférico escrito por la narrativa argentina actual

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Alejandro Gasel

2011-07-01

Full Text Available http://dx.doi.org/10.5007/1984-784X.2011v11n16p50 La comunicación consiste en la exposición de las formas de la inscripción de la Patagonia Austral en la contemporaneidad de la narrativa argentina. Puntualmente pensando dos novelas: Falsa Calma de Sonia Cristoff (2004 y La Siberia de Cristina Siscar (2006 trataremos de razonar qué sigue de vigente y qué aparece como una rehabilitación de este territorio en el proceso de producción narrativa. En este sentido, pensamos que podemos plantear no solamente el fenómeno de la representación actual de este territorio sino la productividad reconocida en los textos a partir de un juego intertextual, que sincretiza a una memoria precedente que ha descripto y inscripto el territorio con la necesidad de referencia la crisis del presente o actualidad del territorio en formas de umbralidad. Para dar cuenta de este proceso hemos de remitirnos a pensar la enunciación de los textos, los usos de géneros discursivos, en especial, el relato viaje y la implicancia de la historia y la memoria para referirse políticamente a la Patagonia Austral argentina que sigue siendo tematizado en el variopinto paisaje de la Literatura Argentina.
GEOPOLITICS AND TRANSPORTATION. UNITED STATES AND PANAMA CANAL

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Benea Ciprian Beniamin

2009-05-01

Full Text Available This article presents the great connection which exists between the realization of Panama Canal and the rising power on United States; and how this state, after the construction of this canal, could promote efficiently at global level its interests.
SCADA system with predictive controller applied to irrigation canals

OpenAIRE

Figueiredo, João; Botto, Miguel; Rijo, Manuel

2013-01-01

This paper applies a model predictive controller (MPC) to an automatic water canal with sensors and actuators controlled by a network (programmable logic controller), and supervised by a SCADA system (supervisory control and a data acquisition). This canal is composed by a set of distributed sub-systems that control the water level in each canal pool, constrained by discharge gates (control variables) and water off-takes (disturbances). All local controllers are available through an industria...
Endodontic management of a mandibular first molar with six root canal systems.

Science.gov (United States)

Jain, Dilip; Reddy, Smitha; Venigalla, Bhuvan Shome; Kamishetty, Shekhar

2015-01-01

Internal anatomy of pulp is complex. The first mandibular molars typically have two roots, one mesial with two root canals and another distal root, which contains one or two canals. A 20-year-old female patient reported with intermittent pain and incomplete root canal treatment in left lower back region since 1-week. Refined access cavity revealed initially two canals in mesial and two canals in the distal root. With operating microscope and cone beam computerized tomography, two additional canals (L-mesio-buccal and B-mesio-lingual) were identified in mesial root. One-year follow-up showed patient was asymptomatic and complete healing of periapical radiolucency.
Topographical evaluation of the mandibular canal through panoramic radiograph

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Ingrid Macedo Oliveira

2016-10-01

Full Text Available The mandibular canal is located inside the body of the mandible and may have anatomical variations. The topographic knowledge of the mandibular canal by the Dental surgeons is fundamental to achieving success in surgical planning, anesthetics and clinical interventions involving the jaw. To study the anatomy of the mandibular canal through panoramic radiographs. A retrospective descriptive study, developed after review and approval by the Ethics and Research Committee with the number of opinion 431095. Were analyzed 252 panoramic radiographs of patients of male and female attended in dental clinics UNINOVAFAPI University Center, Teresina-Pi, Brazil. The radiographs were analyzed with the aid of a light box and each antimere the jaw was observed separately. The classification of Nortjé and Langlais for description of the topography of the mandibular canal were used. Descriptive statistical analysis was performed with SPSS version 18.0. There was a prevalence of 38.89% in both antimeres, of mandibular channel the Type II. The type IV was present in 25.4% in the right hemi-arch and 26.6% on the left. Mandibular canal with unilateral bifurcation was observed in 0.77% of the sample and molar straight channel has not been identified. We observed anatomical variations as for the number and path, of the mandibular canal with the highest prevalence of Types II and IV, and the absence of bifurcations. Most was mandibular channels showed no bifurcation. The panoramic radiograph showed up an aid important to identify the mandibular canal and its variations.
Cervical spinal canal narrowing and cervical neurologi-cal injuries

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ZHANG Ling

2012-04-01

Full Text Available 【Abstract】Cervical spinal canal narrowing can lead to injury of the spinal cord and neurological symptoms in-cluding neck pain, headache, weakness and parasthesisas. According to previous and recent clinical researches, we investigated the geometric parameters of normal cervical spinal canal including the sagittal and transverse diameters as well as Torg ratio. The mean sagittal diameter of cervical spinal canal at C 1 to C 7 ranges from 15.33 mm to 20.46 mm, the mean transverse diameter at the same levels ranges from 24.45 mm to 27.00 mm and the mean value of Torg ratio is 0.96. With respect to narrow cervical spinal canal, the following charaterstics are found: firstly, extension of the cervical spine results in statistically significant stenosis as compared with the flexed or neutral positions; secondly, females sustain cervical spinal canal narrowing more easily than males; finally, the consistent narrowest cervical canal level is at C 4 for all ethnicity, but there is a slight variation in the sagittal diameter of cervical spinal stenosis (≤14 mm in Whites, ≤ 12 mm in Japanese, ≤13.7 mm in Chinese. Narrow sagittal cervical canal diameter brings about an increased risk of neurological injuries in traumatic, degenerative and inflam-matory conditions and is related with extension of cervical spine, gender, as well as ethnicity. It is hoped that this re-view will be helpful in diagnosing spinal cord and neuro-logical injuries with the geometric parameters of cervical spine in the future. Key words: Spinal cord injuries; Spinal stenosis; Trauma, nervous system
Superior Canal Dehiscence Syndrome: Lessons from the First 20 Years

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Bryan K. Ward

2017-04-01

Full Text Available Superior semicircular canal dehiscence syndrome was first reported by Lloyd Minor and colleagues in 1998. Patients with a dehiscence in the bone overlying the superior semicircular canal experience symptoms of pressure or sound-induced vertigo, bone conduction hyperacusis, and pulsatile tinnitus. The initial series of patients were diagnosed based on common symptoms, a physical examination finding of eye movements in the plane of the superior semicircular canal when ear canal pressure or loud tones were applied to the ear, and high-resolution computed tomography imaging demonstrating a dehiscence in the bone over the superior semicircular canal. Research productivity directed at understanding better methods for diagnosing and treating this condition has substantially increased over the last two decades. We now have a sound understanding of the pathophysiology of third mobile window syndromes, higher resolution imaging protocols, and several sensitive and specific diagnostic tests. Furthermore, we have a treatment (surgical occlusion of the superior semicircular canal that has demonstrated efficacy. This review will highlight some of the fundamental insights gained in SCDS, propose diagnostic criteria, and discuss future research directions.
A review of potential tsunami impacts to the Suez Canal

Science.gov (United States)

Finkl, C.; Pelinovsky, E.

2012-04-01

Destructive tsunamis in the eastern Mediterranean and Red seas, induced by earthquakes and/or volcanic activity, pose potential hazards to docked seaport shipping and fixed harbor infrastructure as well as to in-transit international shipping within the Suez Canal. Potential vulnerabilities of the Suez Canal to possible tsunami impacts are reviewed by reference to geological, historical, archaeoseismological, and anecdotal data. Tsunami catalogues and databases compiled by earlier researchers are perused to estimate potential return periods for tsunami events that could affect directly the Suez Canal and its closely associated operational infrastructures. Analysis of these various records indicates a centurial return period, or multiples thereof, for long-wave repetition that could generally affect the Nile Delta. It is estimated that tsunami waves 2 m high would have a breaking length about 5 km down Canal whereas a 10 m wave break would occur about 1 km into the Canal. Should a tsunami strike the eastern flanks of the Nile Delta, it would damage Egypt's maritime infrastructure and multi-national commercial vessels and military ships then using the Canal.
Study of mastoid canals and grooves in north karnataka human skulls.

Science.gov (United States)

Hadimani, Gavishiddappa Andanappa; Bagoji, Ishwar Basavantappa

2013-08-01

This study was undertaken to observe the frequency of mastoid canals and grooves in north Karnataka dry human skulls. 100 dry human skulls of unknown age and sex from the department of Anatomy were selected and observed for the present study. The mastoid regions of dry skulls were observed for the presence of mastoid canals and grooves, if any. A metallic wire was passed through the canal for its confirmation and then the length was measured. The Mastoid canals were present in 53% of the total 100 skulls observed either bilaterally or unilaterally. Mastoid grooves were present in 18% of the total skulls (100) observed. Double mastoid canal was found in 01% of total skull studied and both Mastoid canals & Mastoid grooves together were present in 02% of the total skulls (100) observed. The knowledge of mastoid canals and grooves is very important for otolaryngologists and neurosurgeons. Because they contain an arterial branch of occipital artery with its accompanying vein which is liable to injury resulting into severe bleeding.
Shaping ability of nickel-titanium rotary instruments in curved root canals.

Science.gov (United States)

Talati, Ali; Moradi, Saeed; Forghani, Maryam; Monajemzadeh, Ali

2013-01-01

Disinfection and subsequent obturation of the root canal space require adequate mechanical enlargement of the canals. The purpose of this in vitro study was to compare the shaping ability of Mtwo, RaCe and Medin rotary instruments during the preparation of curved root canals. Sixty mesiobuccal root canals of mandibular molars with severe curvatures between 25-35(°) and radius of 4-9 mm were randomly divided into three groups of 20 canals each. Using pre- and post-instrumentation radiographs, straightening of the canal and the apical transportation were determined with AutoCAD software. The data were analyzed using Chi square, analysis of variance, and post-hoc tests and the significance level was set at P0.05). Under the conditions of this in vitro study, Mtwo instruments seemed superior to the two other rotary instruments.
A widespread devonian methamorphic episode in northern Patagonia, Argentina

International Nuclear Information System (INIS)

Ostera, H.A.; Linares, E; Haller, M.J; Cagnoni, M.C.; Lopez de Luchi, M

2001-01-01

One of the greatest difficulties in Rb-Sr dating on metamorphic rocks is the lack of evidences of complete re-homogenization and the assumption of a common initial ratio for all the samples analyzed. The redistribution of parent-daughter elements and the concomitant partial or complete equilibration of the isotopic system could occur on mineral or regional size domains. This fact led to many authors to discard or disapprove the use of this method in metamorphic terranes. However, recent papers suggested that this opinion has been premature and that additional information could be obtained by the Rb-Sr method despite the difficulties that it implies (Patel et al., 1999). Many reports on well fitted Rb-Sr isochrons giving the age of metamorphism in regionally metamorphosed rocks, suggest that the Sr isotopic equilibrium can take place at different scales. This paper presents data and the Rb-Sr system behaviour from a metamorphic unit (Cushamen Formation) in the Northern Patagonia, as a contribution to elucidate the evolution of the North Patagonian Massif (au)
Two-Rooted Maxillary First Molars with Two Canals: A Case Series

OpenAIRE

Shakouie, Sahar; Mokhtari, Hadi; Ghasemi, Negin; Gholizadeh, Seddigheh

2013-01-01

Thorough understanding of the anatomic and internal morphology of a root canal system is absolutely essential for the success of endodontic treatment. Since permanent maxillary first molars have shown variation in internal anatomy, morphology, this tooth has been reviewed extensively. Presence of two canals in a two-rooted maxillary first molar has rarely been reported in studies describing tooth and root canal anatomies. In this report, three cases are presented, which involve the root canal...
Effect of Suez Canal Marine Sediment on Sorption of Cesium

International Nuclear Information System (INIS)

Hassan, H.B.

2016-01-01

Suez Canal is surrounded by navigation, industrial, agricultural activities and suffers from high rate of population growth that discharging waste into Suez Canal. The Suez Canal coastal waters are influenced by a complex variety of physical, geochemical and biological processes, which influence the behavior, transport and fate of containments released into the marine environment. Sorption of releasing containment such as cesium in Suez Canal water is investigated because of its toxic effect on the marine environment. The object of present study is to determine the effects some of physical and chemical characteristics of collected sediment samples from the three important locations on Suez Canal (Suez Bay, Bitter Lakes and El- Temsah Lake beaches) on sorption behavior of cesium by using batch experiment. Batch experiment was used to study the sorption of the cesium ion. The sorption process is dependent on mineral constituents of Suez Canal sediment and their characteristics. Analytical methods which included particle size and X-ray diffraction (XRD) analyses found that particle size of Suez Canal sediment samples is characterized by sand to fine sand and quartz is the main mineralogical species. Distribution coefficient (K d ) which represent geochemical processes and particle size of these sediment samples effect on the degree of cesium sorption to the sediment. Also (K d ) increase with increase cation exchangeable capacity (CEC). The Suez Canal sediment samples have low (K d ) values which effected by their physical and chemical properties. Sample (2) has highest distribution coefficient (K d ) between measured samples due to containing ratio 30% of fine sand and high ratio of organic matter.
Viperous fangs: development and evolution of the venom canal.

Science.gov (United States)

Zahradnicek, Oldrich; Horacek, Ivan; Tucker, Abigail S

2008-01-01

Fangs are specialised long teeth that contain either a superficial groove (Gila monster, Beaded lizard, some colubrid snakes), along which the venom runs, or an enclosed canal (viperid, elapid and atractaspid), down which the venom flows inside the tooth. The fangs of viperid snakes are the most effective venom-delivery structures among vertebrates and have been the focus of scientific interests for more than 200 years. Despite this interest the questions of how the canal at the centre of the fang forms remains unresolved. Two different hypotheses have been suggested. The mainstream hypothesis claims that the venom-conducting canal develops by the invagination of the epithelial wall of the developing tooth germ. The sides of this invagination make contact and finally fuse to form the enclosed canal. The second hypothesis, known as the "brick chimney", claims the venom-conducting canal develops directly by successive dentine deposition as the tooth develops. The fang is thus built up from the tip to the base, without any folding of the tooth surface. In an attempt to cast further light on this subject the early development of the fangs was followed in a pit viper, Trimeresurus albolabris, using the expression of Sonic hedgehog (Shh). We demonstrate that the canal is indeed formed by an early folding event, resulting from an invagination of epithelial cells into the dental mesenchyme. The epithelial cells proliferate to enlarge the canal and then the cells die by apoptosis, forming an empty tube through which the poison runs. The entrance and discharge orifices at either end of the canal develop by a similar invagination but the initial width of the invagination is very different from that in the middle of the tooth, and is associated with higher proliferation. The two sides of the invaginating epithelium never come into contact, leaving the orifice open. The mechanism by which the orifices form can be likened to that observed in reptiles with an open groove along
CT and MR Imagings of Semicircular Canal Aplasia

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Shin, Chung Hee; Hong, Hyun Sook; Yi, Beom Ha; Cha, Jang Gyu; Park, Seong Jin; Kim, Dae Ho; Lee, Hae Kyung; Kim, Shi Chan [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

2009-07-15

To evaluate the clinical, CT and MR imaging findings of semicircular canal (SCC) aplasia and to evaluate if a correlation exists between these findings and the associated anomalies or syndromes. This study retrospectively reviewed the CT and MRI findings of five patients with SCC aplasia. The CT and MR findings were analyzed for SCC, direction of facial nerve canal, cochlea, vestibule, oval or round window, middle ear ossicles, and internal auditory canal (IAC). The subjects included three boys and two girls ranging in age from one to 120 months (mean age; 51 months). Four of the subjects had the CHARGE syndrome, and one had the Goldenhar syndrome. Moreover, four subjects had sensorineural hearing loss and one had combined hearing loss. The course of the facial nerve canal was abnormal in all five cases. Moreover, trapped cochlea and dysplastic modiolus were each observed in one case. Four subjects had atresia of the oval window; whereas ankylosis of the ossicles was present in three subjects. IAC stenosis was present in one patient with the CHARGE syndrome. The aberrant course of the facial nerve canal, atresia of the oval window, and abnormal ossicles were frequently associated in patients with SCC aplasia. In addition, the Goldenhar and CHARGE syndromes were also commonly associated syndromes.
Kyphoplasty for osteoporotic fractures with spinal canal compromise

International Nuclear Information System (INIS)

Gan Minfeng; Yang Huilin; Zou Jun; Wang Genlin; Mei Xin; Zhou Feng; Chen Liang; Jiang Weimin

2010-01-01

Objective: To explore the feasibility and clinical outcome of kyphoplasty in the treatment of osteoporotic fractures with canal compromise. Methods: A total of 16 patients with osteoporotic fractures with canal compromise without neurological deficit were attempted to be treated by kyphoplasty. During kyphoplasty, modified techniques including staged bone cement injection and dynamic fluoroscopic monitoring were used. Pain was measured using the self-reporting Visual Analogue pain Scale (VAS) preoperatively, postoperatively and in the final follow-up. Disability was measured using the Oswestry Disability questionnaire (ODI) preoperatively, postoperatively and in the final follow-up. The height of the compromised vertebral body, the kyphotic angle and the spinal canal compromise were measured preoperatively, postoperatively and in the final follow-up. Results: Operations were completed smoothly, with the exception of one patient with less cement leakage but without clinical symptom occurred. Relief of pain was achieved after kyphoplasty. The mean VAS score of these patients decreased from 8.1 ± 1.2 pre-operatively to 2.7 ± 0.6 post-operatively (P 0.05). In the final follow-up, the spinal canal compromise was (14.4 ± 3.1)%. Conclusion: Kyphoplasty is a relatively safe and effective method for the treatment of osteoporotic fractures with canal compromise without neurological deficit. (authors)
INVITACIÓN AL GEOTURISMO. REFLEXIONES SOBRE GEODIVERSIDAD Y POTENCIAL GEOTURÍSTICO EN LA PATAGONIA ARGENTINA

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María de la Paloma Martínez Fernandez

2013-12-01

Full Text Available Geotourism as a type of nature tourism comes to fill an empty field on the use of geological resources of the landscape in Argentina. With an approach sustained by the ideas and progresses achieved along the last decades about sustainable tourism, geosites and geoparks are getting a boost worldwide. However, in Argentina this concept has not being incorporated yet within public or private touristic policies, despite owning a valuable geodiversity both scientific or aesthetically. Based on a review of concepts and foreign experiences on the subject, this article analyses the possibilities and parameters for geotourism developing in Argentinean Patagonia.
Diacronía y sincronía del contacto lingüístico en Patagonia sur

OpenAIRE

Virkel, Ana Ester

2012-01-01

Desde su integración al Estado argentino, la región patagónica fue receptora de inmigrantes de muy diversas procedencias, quienes, integrándose con las etnias aborígenes preexistentes, configuraron un contexto multiétnico y multicultural, con la consiguiente diversidad lingüística. El propósito de este trabajo es trazar un esquemático itinerario a través de la historia lingüística de Chubut, Patagonia sur, focalizando el interés en una serie de procesos migratorios que impactan de modo sus...
Mechanics of the Panama Canal slides

Science.gov (United States)

Becker, George F.

1917-01-01

Dr. Becker visited the Canal Zone in 1913 as a geologist of the United States Geological Survey and since that time has given the problem the benefit of his study. His appointment as a member of the committee of the National Academy of Sciences has made it appropriate for his conclusions, based upon his personal observations and already reported in part to the Canal Commission, to be stated for the benefit of his associates and other American scientists and engineers.
Root canal treatment of a maxillary first premolar with three roots

OpenAIRE

Mathew, Josey; Devadathan, Aravindan; Syriac, Gibi; Shamini, Sai

2015-01-01

Successful root canal treatment needs a thorough knowledge of both internal and external anatomy of a tooth. Variations in root canal anatomy constitute an impressive challenge to the successful completion of endodontic treatment. Undetected extra roots and canals are a major reason for failed root canal treatment. Three separate roots in a maxillary first premolar have a very low incidence of 0.5?6%. Three rooted premolars are anatomically similar to molars and are sometimes called ?small mo...

CANAL code

International Nuclear Information System (INIS)

Gara, P.; Martin, E.

1983-01-01

The CANAL code presented here optimizes a realistic iron free extraction channel which has to provide a given transversal magnetic field law in the median plane: the current bars may be curved, have finite lengths and cooling ducts and move in a restricted transversal area; terminal connectors may be added, images of the bars in pole pieces may be included. A special option optimizes a real set of circular coils [fr
Endodontic management of radix paramolaris with six canals: a clinical case report.

Science.gov (United States)

Acharya, N; Singh, A; Samant, P S; Gautam, V

2013-01-01

Endodontic therapy of mandibular molars is a challenging task due to its varied root canal morphology. A mandibular first molar with additional buccal root (Radix paramolaris) and additional distolingual root (Radix Entomolaris) is an example of its varied anatomy. A successful management of atypical root canal configurations is an important aspect in determining the success rate of root canal therapy. The detail knowledge of the root morphology and canal anatomy allows the clinician for accurate location of the extra roots and canals and accordingly the refinement of the access cavity for the stress free entry of complex anatomy. Hence, for a successful root canal therapy, clinician must be aware of the external and internal anatomic variations .The aim of this clinical case report is to present and describe the unusual presence of two separate mesial roots and six root canals in mandibular first molar, detected during routine endodontic therapy.
Root canal morphology of primary molars: a micro-computed tomography study.

Science.gov (United States)

Fumes, A C; Sousa-Neto, M D; Leoni, G B; Versiani, M A; da Silva, L A B; da Silva, R A B; Consolaro, A

2014-10-01

This was to investigate the root canal morphology of primary molar teeth using micro-computed tomography. Primary maxillary (n = 20) and mandibular (n = 20) molars were scanned at a resolution of 16.7 μm and analysed regarding the number, location, volume, area, structured model index (SMI), area, roundness, diameters, and length of canals, as well as the thickness of dentine in the apical third. Data were statistically compared by using paired-sample t test, independent sample t test, and one-way analysis of variance with significance level set as 5%. Overall, no statistical differences were found between the canals with respect to length, SMI, dentine thickness, area, roundness, and diameter (p > 0.05). A double canal system was observed in the mesial and mesio-buccal roots of the mandibular and maxillary molars, respectively. The thickness in the internal aspect of the roots was lower than in the external aspect. Cross-sectional evaluation of the roots in the apical third showed flat-shaped canals in the mandibular molars and ribbon- and oval-shaped canals in the maxillary molars. External and internal anatomy of the primary first molars closely resemble the primary second molars. The reported data may help clinicians to obtain a thorough understanding of the morphological variations of root canals in primary molars to overcome problems related to shaping and cleaning procedures, allowing appropriate management strategies for root canal treatment.
Optimizing the chemical aspect of root canal irrigation

NARCIS (Netherlands)

de Macedo, R.G.

2013-01-01

Root canal treatment is aimed at the removal of inflamed and infected tissue present in the root canal system. It will prevent the entrance of new microorganisms or nutrients in order to maintain or create a healthy environment around the root. There is sufficient evidence that shows that
Forced extrusion for removal of impacted third molars close to the mandibular canal Extrusión forzada para extraer los terceros molares impactados cerca del canal mandibular

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Dennis Flanagan DDS

2012-03-01

Full Text Available Impacted mandibular third molars can be located in close proximity to the mandibular canal. This creates a risk for the nerve or artery injury. These are contained in the canal. However, the impacted third molar can be moved coronally by orthodontic means, after removal of overlying bone, and safely extracted. The orthodontic intervention slowly moves the tooth apex away from the mandibular canal and reduces the potential for a neural injury. This method may be useful for older patients with root apices that approximate or are actually located in the mandibular canal. This technique needs further study. There is a theoretical potential for neural or arterial injury from physical contact of the tooth apex as it moves by or through the mandibular canal.Los terceros molares inferiores impactados pueden localizarse muy cerca del canal mandibular. Esto constituye un riesgo de lesión del nervio o la arteria, que se localizan dentro del canal. No obstante, el tercer molar impactado puede desplazarse en dirección coronal con ortodoncia, tras ostectomía del hueso suprayacente, y extraerse sin riesgos. La intervención ortodóncica desplaza lentamente el ápice del diente fuera del canal mandibular y reduce la posibilidad de lesión neural. Este método puede ser útil para pacientes de edad avanzada con ápices dentales que se aproximan o en realidad se localizan en el canal mandibular. La técnica necesita un estudio adicional. Hay la posibilidad teórica de lesión neural o arterial a partir del contacto físico del ápice del diente a medida que se desplaza a través del canal mandibular.
Three-dimensional analysis of mesiobuccal root canal of Japanese maxillary first molar using Micro-CT

International Nuclear Information System (INIS)

Yamada, Masashi; Ide, Yoshinobu; Matsunaga, Satoru; Kato, Hiroshi; Nakagawa, Kan-Ichi

2011-01-01

The objective of this study was to three-dimensionally observe the morphological characteristics of mesiobuccal root canals of Japanese maxillary first molars using microcomputed tomography (Micro-CT) and classify root canal variations. This study used 90 maxillary first molars. Three-dimensional reconstruction was performed using data obtained by Micro-CT, and cross-sections of the root canals were observed. Moreover, the root canal morphology was classified by the configuration and root canal diameter, and was evaluated for occurrence using the classification by Weine et al. (1969) as a reference. Overall, single root canals were observed in 44.4%, incomplete separation root canals in 22.3%, and completely separate root canals (upper and lower separation root canals) in 33.3%. Mesiobuccal root canals often had intricate configurations, and accessory root canals (lateral canals and apical ramifications) were observed in most of the mesiobuccal root canals (76.7%), irrespective of whether there were ramifications of the main root canals. While there were no marked differences in the incidence of root canal ramifications between this study and earlier reports, the incidence of accessory root canals was higher in this study. This result may be explained by the far more superior visualization ability of Micro-CT than conventional methods, which allowed the detection of microscopic apical ramifications previously difficult to observe. (author)
AFSC/ABL: Lynn Canal Overwinter Acoustic Survey, 2004-2005

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The acoustic trawl database for Lynn Canals echo-trawl survey was conducted from 2001 to 2004 throughout southern Lynn Canal in southeast Alaska. Acoustic surveys...
Respuesta del microfitoplancton a la adición de nitrato y ácido silícico en fiordos de la Patagonia chilena

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Pamela Labbé-Ibáñez

2015-03-01

Full Text Available La Patagonia chilena está experimentando un aumento del uso del suelo y océano costero y el acelerado derretimiento de algunos glaciares, por lo que uno de los escenarios a futuro es que los fiordos adyacentes reciban cantidades variables de agua dulce y nutrientes inorgánicos. Se estudió la respuesta de ensambles de fitoplancton de los fiordos Reloncaví en invierno y Comau en primavera, a la adición de nitrato y ácido silícico en experimentos de microcosmos. Los ensambles fitoplanctónicos estudiados respondieron a la adición de nutrientes con incrementos en la abundancia celular biomasa autotrófica (clorofila-a y cambios en la composición específica, destacando el cambio de dominancia de especies de diatomeas pennadas a céntricas formadoras de cadenas. Estos resultados dan indicios acerca de los factores que afectan a las comunidades microalgales en un escenario de cambio climático e intervención antrópica de los fiordos de la Patagonia Norte.
Noble gas composition of subcontinental lithospheric mantle: An extensively degassed reservoir beneath Southern Patagonia

Science.gov (United States)

Jalowitzki, Tiago; Sumino, Hirochika; Conceição, Rommulo V.; Orihashi, Yuji; Nagao, Keisuke; Bertotto, Gustavo W.; Balbinot, Eduardo; Schilling, Manuel E.; Gervasoni, Fernanda

2016-09-01

Patagonia, in the Southern Andes, is one of the few locations where interactions between the oceanic and continental lithosphere can be studied due to subduction of an active spreading ridge beneath the continent. In order to characterize the noble gas composition of Patagonian subcontinental lithospheric mantle (SCLM), we present the first noble gas data alongside new lithophile (Sr-Nd-Pb) isotopic data for mantle xenoliths from Pali-Aike Volcanic Field and Gobernador Gregores, Southern Patagonia. Based on noble gas isotopic compositions, Pali-Aike mantle xenoliths represent intrinsic SCLM with higher (U + Th + K)/(3He, 22Ne, 36Ar) ratios than the mid-ocean ridge basalt (MORB) source. This reservoir shows slightly radiogenic helium (3He/4He = 6.84-6.90 RA), coupled with a strongly nucleogenic neon signature (mantle source 21Ne/22Ne = 0.085-0.094). The 40Ar/36Ar ratios vary from a near-atmospheric ratio of 510 up to 17700, with mantle source 40Ar/36Ar between 31100-6800+9400 and 54000-9600+14200. In addition, the 3He/22Ne ratios for the local SCLM endmember, at 12.03 ± 0.15 to 13.66 ± 0.37, are higher than depleted MORBs, at 3He/22Ne = 8.31-9.75. Although asthenospheric mantle upwelling through the Patagonian slab window would result in a MORB-like metasomatism after collision of the South Chile Ridge with the Chile trench ca. 14 Ma, this mantle reservoir could have remained unhomogenized after rapid passage and northward migration of the Chile Triple Junction. The mantle endmember xenon isotopic ratios of Pali-Aike mantle xenoliths, which is first defined for any SCLM-derived samples, show values indistinguishable from the MORB source (129Xe/132Xe =1.0833-0.0053+0.0216 and 136Xe/132Xe =0.3761-0.0034+0.0246). The noble gas component observed in Gobernador Gregores mantle xenoliths is characterized by isotopic compositions in the MORB range in terms of helium (3He/4He = 7.17-7.37 RA), but with slightly nucleogenic neon (mantle source 21Ne/22Ne = 0.065-0.079). We
Direct and CT measurements of canals and foramina of the skull base

International Nuclear Information System (INIS)

Berlis, A.; Schumacher, M.; Putz, R.

1992-01-01

This investigation is based on measurements of 60 macerated adult European skulls from the Alexander-Ecker Collection at the Anatomy Department of the University of Freiburg. Computer tomographical (CT) and anatomical measurements were compared to assess the accuracy of the CT representation of osseous structures. Nine structures were examined: the optic canal, superior orbital fissure, foramen rotundum, foramen ovale, foramen spinosum,foramen Vesalii (venosum), carotid canal, internal auditory canal and hypoglossal canal. Results show a good and even excellent correlation if the cranial opening is approximately at a right angle to the scanline. For this reason, the results of the coronal examination of the internal auditory canal are less satisfactory, and the coronal and axial measurements of the hypoglossal canal show only a moderately good correlation. (author)
On the ecological role of Copepoda in the Suez Canal marine ...

African Journals Online (AJOL)

Moreover, the importance of copepods in the marine food web and secondary productivity in the canal water, as well as their response to environmental variations in the Suez Canal ecosystem were discussed. KEY WORDS: Zooplankton, Copepoda, food web, marine ecosystem, Suez Canal Egyptian Journal of Biology ...
Root canal treatment of bilateral three-rooted maxillary first premolars

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Bhavana Gandhi

2012-01-01

Full Text Available In endodontics, several anatomic variations occur in teeth, both externally and in the internal root morphology, which play a very significant role in the diagnosis and treatment outcome. A thorough knowledge of the root canal anatomy, careful interpretation of the angled radiographs, proper endodontic access cavity preparation, and exploration of the root canal are the prerequisites for endodontic success. In a maxillary first premolar, it is rare to find extra roots and canals, and the aim of the present article is to report a case about the successful diagnosis and clinical management of bilateral three-rooted maxillary first premolars, with three independent root canals.
Radioactivity level of the gamma emitters in Ismailia Canal environment

International Nuclear Information System (INIS)

Abdel Malik, W.E.Y.; Youssef, S.K.; Ibrahim, A.S.

1993-01-01

The activity level of the γ-emitting radionuclides was measured in the different component of Ismalia Canal (bottom sediment, biota and water) by γ-spectrometry. The average activity level of the dry samples ranged from 12 to 89 Bq/kg for the detected natural radionuclides. The annual external γ-dose to the living organisms in the canal, close to the sediment beds, was found to be in the range of 1.21±0.24 mSv/y and does not present any significant hazards when compared with the natural γ-ray background around the Ismalia Canal(IC) environment which ranges from 0.80 to 1.73 mSv/y. (orig.)
Radiographic analysis of odontogenic cysts showing displacement of the mandibular canal

International Nuclear Information System (INIS)

Cho, Bong Hae

2003-01-01

To assess the radiographic findings of odontogenic cysts showing displacement of the mandibular canal using computed tomographic (CT) and panoramic images. CT and panoramic images of 63 odontogenic cysts (27 dentigerous, 16 odontogenic keratocysts, and 20 radicular cysts) were analyzed to evaluate the following parameters: the dimension and shape of the cysts, and the effect of the cysts on the mandibular canal and cortical plates. Of the 63 cysts examined in the study, 35 (55.6%) showed inferior displacement of the mandibular canal and 46 (73.0%) showed perforation of the canal. There were statistically significant differenced between CT and panoramic images in depicting displacement and perforation of the mandibular canal. Cortical expansion was seen in 46 cases (73.0%) and cortical perforation in 23 cases (36.5%). The radicular cysts showed cortical expansion and perforation less frequently than the other cyst groups. Large cysts of mandible should be evaluated by multiplanar CT images in order to detect the mandibular canal and cortical bone involvement.
Root and Canal Morphology of Mandibular Third Molars in an Iranian Population

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Maryam Kuzekanani

2012-06-01

Full Text Available Background and aims. A through knowledge of the root canal morphology is required for successful endodontic therapy. The aim of this study was to investigate the root and canal morphology of mandibular third molars in Kerman, a province in southeast of Iran. Materials and methods. One-hundred-fifty extracted mandibular third molars were collected randomly from different dental clinics in Kerman. The root canal anatomy and morphology of each tooth was carefully studied using a clearing technique. Root number and morphology, number of canals per root, root canal configuration according to Vertucci classification, and incidence of dilacerated roots and C-shaped canals in mandibular third molars were evaluated under stereomicroscope with ×2 to ×3 magnifications. Results. From the total of 150 mandibular third molars studied, 21% had one root. The majority of teeth (73% had two roots. 5.5% of the teeth had three roots. The incidence of C-shaped canal was 3.5% in this study and 8% of the teeth had at least one dilacerated root. Conclusion. Although root canal anatomy and morphology of mandibular third molars is very variable having two roots seems to be the normal anatomy for these teeth.
Effectiveness of Various Irrigation Protocols in Removing Calcium Hydroxide from Root Canals

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Hakan Göktürk

2018-04-01

Full Text Available Objective: The purpose of this study was to investigate the removal efficiency of calcium hydroxide (CH by CanalBrush, Vibringe, laser-activated irrigation (LAI, conventional syringe irrigation (CSI, XP-endo Finisher, and passive ultrasonic irrigation (PUI in the root canal walls. Materials and Methods: Ninety-eight human mandibular premolar teeth were prepared. Root canals were filled with CH. The roots were divided into six experimental groups (n=15/group according to the irrigation protocol used: group 1 (CSI, group 2 (Vibringe, group 3 (CanalBrush, group 4 (XP-endo Finisher, group 5 (PUI, and group 6 (LAI. The amount of residual CH in the canal walls for each canal third was scored. Data were analysed by using Kruskal-Wallis and Bonferroni-correction Mann-Whitney U tests. Results: None of the investigated protocols renders the root canal walls free of CH remnants. Significant differences were found between tooth regions in terms of CH removal (p<0.05, and all groups except group 6 (LAI showed more residual CH in the apical region. PUI and LAI eliminated significantly more CH than CSI from the middle and apical thirds of the root canal, respectively. Conclusion: The activation of sodium hypochlorite with various devices increased CH removal at the apical and middle part of the canal. LAI and PUI produce better results in the apical and middle thirds, respectively.
A central incisor with 4 independent root canals: a case report

NARCIS (Netherlands)

Aznar Portoles, C.; Moinzadeh, A.T.; Shemesh, H.

2015-01-01

The maxillary central incisor is the tooth with the least anatomic variations. Despite the fact that several studies have reported a prevalence of 100% for the presence of a single canal, root canal aberrations of maxillary central incisors with up to 3 canals have also been reported. Such cases
Two-rooted maxillary first molars with two canals: a case series.

Science.gov (United States)

Shakouie, Sahar; Mokhtari, Hadi; Ghasemi, Negin; Gholizadeh, Seddigheh

2013-01-01

Thorough understanding of the anatomic and internal morphology of a root canal system is absolutely essential for the success of endodontic treatment. Since permanent maxillary first molars have shown variation in internal anatomy, morphology, this tooth has been reviewed extensively. Presence of two canals in a two-rooted maxillary first molar has rarely been reported in studies describing tooth and root canal anatomies. In this report, three cases are presented, which involve the root canal treatment of maxillary first molars with fusion of the two buccal roots.
File list: His.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.CDV.05.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.05.AllAg.Atrioventicular_canals.bed ...
File list: Unc.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.CDV.20.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canals http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.20.AllAg.Atrioventicular_canals.bed ...

File list: Unc.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.CDV.05.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.05.AllAg.Atrioventicular_canals.bed ...
File list: His.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.CDV.20.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.20.AllAg.Atrioventicular_canals.bed ...
File list: Unc.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.CDV.50.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.50.AllAg.Atrioventicular_canals.bed ...
File list: His.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.CDV.10.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.10.AllAg.Atrioventicular_canals.bed ...
File list: His.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available His.CDV.50.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.50.AllAg.Atrioventicular_canals.bed ...
File list: Unc.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.CDV.10.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.10.AllAg.Atrioventicular_canals.bed ...
QUANTITATIVE SIZE ASSESSMENT OF THE LUMBAR SPINAL CANAL BY COMPUTED TOMOGRAPHY

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M. Midia Z. Miabi

2007-08-01

Full Text Available By determining normal ranges of spinal canal diameters we can make early diagnosis in persons who have lower diameters of spinal canal. These persons are predisposed to spinal canal stenosis that is a major cause of spinal radiculopathies. In different studies performed in several countries, minimum and maximum ranges of spinal canal diameters were different for each population. In this study, we tried to determine the mean values of normal spinal canal diameters and areas in Tabriz and its suburb. 39 healthy, young to mid-age cases were selected. Our study was focused on L3-L4 and L4-L5. The following parameters were measured: the area of cross-section of the vertebral body, the area of cross-section of the dural sac, interarticular diameter, interligamentous diameter, antero-posterior diameter of the lumbar canal, inter-pedicular diameter, and the area of cross-section of the vertebral canal. A correlation between the parameters studied and the height of subjects was significant for interligamentous diameter (for L3/L4 and L4/L5 and interarticular diameter (only at L3/L4, cross-section area of the vertebrae (both L3 and L4, cross-section area of vertebral canal (only at L5 level, area of dural sac (at L3/L4 and L4. It was suggested that these diameters and areas should be interpreted as a unction of height of the subject. Most of diameters studied had smaller means than those in previous studies. This can be attributed to differences between populations and it can be interpreted as predisposition to spinal canal stenosis in our population.
Canal configuration of mandibular first premolars in an Egyptian population

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Hatem A. Alhadainy

2013-03-01

Full Text Available The purpose of this study was to investigate canal configuration of mandibular first premolars in an Egyptian population. Two hundred fifty human extracted mandibular first premolars were collected from Egyptian patients and a small hole in the center of the occlusal surface of each tooth was made perforating the roof of the pulp chamber. Teeth were decalcified by immersing in nitric acid and dehydrated in ascending concentrations of ethyl alcohol. A waterproof black ink was passively injected from the occlusal hole into pulp system and stained teeth were immersed in methyl salicylate solution for clearing. Standardized pictures of the cleared teeth were obtained and anatomical features of the root canal were observed. The average length of the mandibular first premolar teeth was 22.48 ± 1.74 mm, one-rooted teeth were 96.8% and the two-rooted were 3.2%. Vertucci Type I canal configuration represented the highest percentage (61.2% followed by Type V (16.4%, Type IV (13.2%, Type II (5.6% and Type III (2.8%. Vertucci Type VI canal configuration represented the lowest percentage (0.4% and a complex configuration was found in one tooth. Accessory canals were detected in 22.8% and inter-canal connections were observed in 24.8% while 54% showed apical delta. Such knowledge is clinically useful for localization and negotiation of canals of mandibular first premolar, as well as their subsequent management in Egyptian population.
210 Pb fluxes in sediment layers sampled from Northern Patagonia lakes

International Nuclear Information System (INIS)

Ribeiro Guevara, S.; Sanchez, R.; Arribere, M.; Rizzo, A.

2003-01-01

Unsupported 210 Pb fluxes were determined from sediment core inventories in lakes located in Northern Patagonia, Argentina. Total 210 Pb, 226 Ra, associated with supported 210 Pb, and 137 Cs specific activity profiles were measured by gamma-ray spectrometry. Unsupported 210 Pb fluxes showed very low values when compared to other regions, with a 12 fold variation, ranging from 4 to 48 Bq m -2 x y -1 . The linear correlation observed between the 210 Pb fluxes and 137 Cs cumulative fluxes in sediment cores sampled from water bodies within a zone with similar precipitation demonstrated that both radioisotopes behave in the same manner in these systems concerning the processes occurred from fallout to sediment deposition, and that there are no appreciable local or regional sources of unsupported 210 Pb. Positive correlation of 210 Pb fluxes with organic matter contents of the uppermost sediment core layers was also observed. (author)
A Gigantic, Exceptionally Complete Titanosaurian Sauropod Dinosaur from Southern Patagonia, Argentina

Science.gov (United States)

Lacovara, Kenneth J.; Lamanna, Matthew C.; Ibiricu, Lucio M.; Poole, Jason C.; Schroeter, Elena R.; Ullmann, Paul V.; Voegele, Kristyn K.; Boles, Zachary M.; Carter, Aja M.; Fowler, Emma K.; Egerton, Victoria M.; Moyer, Alison E.; Coughenour, Christopher L.; Schein, Jason P.; Harris, Jerald D.; Martínez, Rubén D.; Novas, Fernando E.

2014-01-01

Titanosaurian sauropod dinosaurs were the most diverse and abundant large-bodied herbivores in the southern continents during the final 30 million years of the Mesozoic Era. Several titanosaur species are regarded as the most massive land-living animals yet discovered; nevertheless, nearly all of these giant titanosaurs are known only from very incomplete fossils, hindering a detailed understanding of their anatomy. Here we describe a new and gigantic titanosaur, Dreadnoughtus schrani, from Upper Cretaceous sediments in southern Patagonia, Argentina. Represented by approximately 70% of the postcranial skeleton, plus craniodental remains, Dreadnoughtus is the most complete giant titanosaur yet discovered, and provides new insight into the morphology and evolutionary history of these colossal animals. Furthermore, despite its estimated mass of about 59.3 metric tons, the bone histology of the Dreadnoughtus type specimen reveals that this individual was still growing at the time of death. PMID:25186586
The 'Amstel Canal' in Amsterdam Canal construction as part of the medieval reclamation and drainage system of the Western Netherlands wilderness

Science.gov (United States)

Abrahamse, Jaap-Evert; Kosian, Menne; Weerts, Henk

2013-04-01

Usually, Amsterdam is presented as a river city, with the river Amstel as the trade route towards its hinterland, the IJ sea-branch as the portal to the world and its Dam as a focal point of transshipment and trade. Geomorphological, sedimentological, historical and historical-geographical evidence however, points towards the straight part of the Amstel, now located in Amsterdam, as a drainage canal that was dug in the aftermath of the 'Great Reclamation' of the 11th and 12th centuries. During this period, large parts of the wilderness in Utrecht and Holland were cultivated and put to agricultural use. Prior to the 'Great Reclamations', large oligotrophic (Sphagnum) peat bogs drained by small rivers were characteristic of the entire region. All along the straight Amstel canal, Sphagnum peat is found, which is indicative of the area's former peat bog conditions. The 'Amstel Canal' connected two natural meandering watercourses, one at the north and one at the south of the canal. The soil along both watercourses exists of eutrophic peat, which is indicative of repeated natural flooding. This is a strong indication of the anthropogenous origin of the straight part of the Amstel. The reason for digging the Amstel canal was not to create better trade links; it was a local component of a solution for major regional drainage problems in the provinces of Utrecht and Holland. These problems arose from the silting up of the Rhine rivermouth around 1100AD. Because of this, the precipitation surplus of the entire region could not be drained to the North Sea by this route anymore. This led to increased flooding and subsequently to conflicts between the rulers of Holland and Utrecht. In 1165AD, these conflicts reached a point where the Holy Roman Emperor intervened. The ruling of Barbarossa eventually led to a compromise: Utrecht and Holland redirected the entire drainage system of the region from the North Sea to the Zuiderzee in a concerted effort. This operation consisted of
Nueva especie de Planorbidae (Gastropoda: Basommatophora en la Patagonia chilena: Biomphalaria cristiani sp. nov. First record of Planorbidae (Mollusca: Basommatophora in Chilean Patagonia: Biomphalaria cristiani sp. nov.

Directory of Open Access Journals (Sweden)

Carmen Fuentealba

2012-11-01

Full Text Available En Chile la familia Planorbidae está representada por el género Biomphalaria Preston, 1910, compuesta por siete especies distribuidas desde Isluga hasta el río Puelo. De estas especies, solo B.peregrina, ampliamente distribuida en el neotrópico, y Biomphalaria aymara de Isluga, han sido reconocidas sobre la base de la morfología del sistema reproductor y la rádula, caracteres que fueron utilizados en el presente estudio para diferenciar a Biomphalaria cristiani como nueva especie del grupo y primer registro de la familia en la Patagonia chilena, ampliando su actual rango de distribución. Los caracteres que permiten la diagnosis de B. cristiani son el saco vaginal vestigial truncado, ausencia del desarrollo de los músculos suspensores del pene, vaina del pene corta en relación al prepucio, oviducto largo en relación al espermioducto y vaso deferente más delgado y largo que la vaina del pene, de tamano similar al prepucio. La localidad tipo de Biomphalaria cristiani sp. nov. es Laguna Cisnes (47°7'10.02"S, 72°27'40.65"W, región de Aysén.The family Planorbidae in Chile is represented by the genus Biomphalaria Preston, 1910, consisting of seven species distributed from Isluga to Puelo River. Of these species, only Biomphalaria peregrina widely distributed in the neotropical and Biomphalaria aymara from Isluga are recognized based on the morphology of the reproductive system and radula, characters that were used in the following study to differentiate Biomphalaria cristiani as a new species of this group and first record of the family in Chilean Patagonia, extending its current distribution range. The characters for the diagnosis of B. cristiani are: truncated vestigial vaginal pouch, lack of development of the penis retractor muscles, penis sheath shorter than the prepuce, oviduct longer than the spermiduct and vas deferens thinner and longer than the penis sheath, similar size to the prepuce. The type locality of B. cristiani nov. sp
Piquet Caroline, Histoire du canal de Suez, Paris, Perrin, 2009, 372 p.

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Claudine Piaton

2011-01-01

Full Text Available Les études sur l'histoire du canal de Suez connaissent un regain d'intérêt chez les historiens français. Nathalie Montel avait ouvert la voie en 1998 en publiant un ouvrage passionnant sur le percement du canal, Le chantier du canal de Suez, 1859-1869. Une histoire des pratiques techniques. L'étude s'arrêtait à l'ouverture du canal en 1869, laissant le champ libre à de futurs travaux. La publication en 2008 de l'ouvrage de Caroline Piquet, La Compagnie du canal de Suez, une concession françai...
File list: Pol.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: Pol.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: Pol.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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Lifescience Database Archive (English)

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File list: Pol.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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Lifescience Database Archive (English)

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File list: DNS.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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Teacher's Guide to Canal. The Middlesex Canal: A Role Playing Exercise.

Science.gov (United States)

Holmes, Cary W.; Tedesco, Paul H.

The document consists of a role-playing game and related teacher's guide designed to illustrate decision-making processes leading to the building of the Middlesex Canal in Massachusetts in 1793. The primary educational objective is to involve students in the decision-making process through role play. The game is designed to facilitate…
Strategies of Coping With Stress During Root Canal Therapy

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Zare Jahromi

2015-12-01

Full Text Available Background Endodontic treatment is one of the stress producing situations. Objectives The purpose of this article was to determine the most stressful stage of root canal therapy among endodontists, endodontic residents, and undergraduate dental students and offering some strategies for reducing stress during this treatment. Patients and Methods This descriptive survey comprised three groups. Thirty-six endodontists, 41 endodontic residents, and 47 undergraduate dental students selected by convenience sampling. Participants were asked about age, sex, the most stressful stage of root canal therapy and stress reducing strategies during the procedure. Results The most stressful stage of root canal therapy was endodontic treatment for children in male endodontists and residents, preparing access cavity on crowns in female endodontists, obturation of apically root Resorped canals in female residents, obturation in female students, and preparing access cavity on molar teeth in male students. The most suggested strategy for reducing stress during root canal therapy was related to experience, knowledge, enough study, and technical mastery. Conclusions It is required to consider the strategies during student education in dental schools for both under and post-graduation dental students and better to follow them in workshops for other dentists and even endodontists.
Review of root canal irrigant delivery techniques and devices

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Yeon-Jee Yoo

2011-05-01

Full Text Available Introduction Eliminating the residual debris and bacteria in the root canal system is one of the main purposes of the endodontic treatment. However, the complexity on the anatomy of the root canal system makes it difficult to eliminate the bacterial biofilm existing along the root canal surface and necrotic pulp tissue by mechanical instrumentation and chemical irrigation. Recently, more effective irrigant delivery systems for root canal irrigation have been developed. The purpose of this review was to present an overview of root canal irrigant delivery techniques and devices available in endodontics. Review The contents of this paper include as follows; - syringe-needle irrigation, manual dynamic irrigation, brushes - sonic and ultrasonic irrigation, passive ultrasonic irrigation, rotary brush, RinsEndo, EndoVac, Laser Conclusion Though technological advances during the last decade have brought to fruition new agitation devices that rely on various mechanisms, there are few evidence based study to correlate the clinical efficacy of these devices with improved outcomes except syringe irrigation with needle and ultrasonic irrigation. The clinicians should try their best efforts to deliver antimicrobial and tissue solvent solutions in predictable volumes safely to working length.
Prominent central spinal canal on MRI - normal variant or pathology

International Nuclear Information System (INIS)

Dugal, T.P.; Brazier, D.; Roche, J.

2002-01-01

Full text: The sensitivity of MRI can make differentiation of normal from abnormal challenging.The study investigates whether a visible central spinal canal is pathological or a normal variant. We review eight MRI (mostly on a 1.5 Tesla unit) cases where there is a visible central cavity in keeping with a central canal and review the literature. The central canal is a space in the medial part of the grey-matter commissure between the anterior and posterior horns. Histopathological studies show that the canal is present at birth with the majority showing subsequent involution but is uncommonly imaged on MRI. The main differential diagnosis is syringomyelia which usually presents with deficits in pain and sensation corresponding to the appropriate level often with a demonstrable aetiology. Two thirds of our patients were female with an average age of thirty-six years (range 26-45). The patients were largely asymptomatic or their symptoms appeared unrelated to the imaging findings. Three patients had minor previous trauma and two others had non-bacterial meningitis up to twenty years earlier. No patient had known spinal surgery or trauma.The cavity corresponded tomographically to the expected site of the central canal. The canal was in the thoracic location. The canal diameter ranged from one to five millimetres and its length varied from one half a vertebral body height to extending over the entire thoracic region. Its configuration was either filiform or fusiform, with smooth contours. No predisposing features to suggest syringomyelia or other structural abnormalities were noted. Where Gadolinium was given no abnormal enhancement was observed. These cases add to the literature and suggest that these prominent canals are largely asymptomatic and should be viewed as normal variants. Copyright (2002) Blackwell Science Pty Ltd
Adaptation and penetration of resin-based root canal sealers in root canals irradiated with high-intensity lasers

Science.gov (United States)

Moura-Netto, Cacio; Mello-Moura, Anna Carolina Volpi; Palo, Renato Miotto; Prokopowitsch, Igor; Pameijer, Cornelis H.; Marques, Marcia Martins

2015-03-01

This research analyzed the quality of resin-based sealer adaptation after intracanal laser irradiation. Extracted teeth (n=168) were root canal treated and divided into four groups, according to dentin surface treatment: no laser; Nd:YAG laser (1.5 W, 100 mJ, 15 Hz) diode laser (2.5 W in CW), and Er:YAG laser (1 W, 100 mJ, 10 Hz). The teeth were divided into four subgroups according to the sealer used: AH Plus, EndoREZ, Epiphany, and EpiphanySE. For testing the sealing after root canal obturation, the penetration of silver nitrate solution was measured, whereas to evaluate the adaptation and penetration of the sealer into the dentin, environmental scanning electron microscopy (ESEM) was used. The ESEM images were analyzed using a four-grade criteria score by three evaluators. The inter-examiner agreement was confirmed by Kappa test and the scores statistically compared by the Kruskal-Wallis' test (p<0.05). Both adaptation and sealer penetration in root canals were not affected by the laser irradiation. Nd:YAG and diode laser decreased the tracer penetration for AH Plus, whereas EndoREZ and EpiphanySE performances were affected by Nd:YAG irradiation (p<0.05). It can be concluded that intracanal laser irradiation can be used as an adjunct in endodontic treatment; however, the use of hydrophilic resin sealers should be avoided when root canals were irradiated with Nd:YAG laser.
File list: ALL.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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Lifescience Database Archive (English)

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Lifescience Database Archive (English)

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File list: ALL.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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Cervical spinal canal narrowing in idiopathic syringomyelia

International Nuclear Information System (INIS)

Struck, Aaron F.; Carr, Carrie M.; Shah, Vinil; Hesselink, John R.; Haughton, Victor M.

2016-01-01

The cervical spine in Chiari I patient with syringomyelia has significantly different anteroposterior diameters than it does in Chiari I patients without syringomyelia. We tested the hypothesis that patients with idiopathic syringomyelia (IS) also have abnormal cervical spinal canal diameters. The finding in both groups may relate to the pathogenesis of syringomyelia. Local institutional review boards approved this retrospective study. Patients with IS were compared to age-matched controls with normal sagittal spine MR. All subjects had T1-weighted spin-echo (500/20) and T2-weighted fast spin-echo (2000/90) sagittal cervical spine images at 1.5 T. Readers blinded to demographic data and study hypothesis measured anteroposterior diameters at each cervical level. The spinal canal diameters were compared with a Mann-Whitney U test. The overall difference was assessed with a Friedman test. Seventeen subjects were read by two reviewers to assess inter-rater reliability. Fifty IS patients with 50 age-matched controls were studied. IS subjects had one or more syrinxes varying from 1 to 19 spinal segments. Spinal canal diameters narrowed from C1 to C3 and then enlarged from C5 to C7 in both groups. Diameters from C2 to C4 were narrower in the IS group (p < 0.005) than in controls. The ratio of the C3 to the C7 diameters was also smaller (p = 0.004) in IS than controls. Collectively, the spinal canal diameters in the IS were significantly different from controls (Friedman test p < 0.0001). Patients with IS have abnormally narrow upper and mid cervical spinal canal diameters and greater positive tapering between C3 and C7. (orig.)
Cervical spinal canal narrowing in idiopathic syringomyelia

Energy Technology Data Exchange (ETDEWEB)

Struck, Aaron F. [Massachusetts General Hospital, Department of Neurology, Boston, MA (United States); Carr, Carrie M. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Shah, Vinil [University of California San Francisco, Department of Radiology, San Francisco, CA (United States); Hesselink, John R. [University of California San Diego, Department of Radiology, San Diego, CA (United States); Haughton, Victor M. [University of Wisconsin, Department of Radiology, Madison, WI (United States)

2016-08-15

The cervical spine in Chiari I patient with syringomyelia has significantly different anteroposterior diameters than it does in Chiari I patients without syringomyelia. We tested the hypothesis that patients with idiopathic syringomyelia (IS) also have abnormal cervical spinal canal diameters. The finding in both groups may relate to the pathogenesis of syringomyelia. Local institutional review boards approved this retrospective study. Patients with IS were compared to age-matched controls with normal sagittal spine MR. All subjects had T1-weighted spin-echo (500/20) and T2-weighted fast spin-echo (2000/90) sagittal cervical spine images at 1.5 T. Readers blinded to demographic data and study hypothesis measured anteroposterior diameters at each cervical level. The spinal canal diameters were compared with a Mann-Whitney U test. The overall difference was assessed with a Friedman test. Seventeen subjects were read by two reviewers to assess inter-rater reliability. Fifty IS patients with 50 age-matched controls were studied. IS subjects had one or more syrinxes varying from 1 to 19 spinal segments. Spinal canal diameters narrowed from C1 to C3 and then enlarged from C5 to C7 in both groups. Diameters from C2 to C4 were narrower in the IS group (p < 0.005) than in controls. The ratio of the C3 to the C7 diameters was also smaller (p = 0.004) in IS than controls. Collectively, the spinal canal diameters in the IS were significantly different from controls (Friedman test p < 0.0001). Patients with IS have abnormally narrow upper and mid cervical spinal canal diameters and greater positive tapering between C3 and C7. (orig.)
Aportes de los "intermediarios culturales" en la conformación de los paisajes fronterizos del norte de la patagonia a fines del siglo XVIII

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Laura Aylén Enrique

2012-12-01

Full Text Available A fines del siglo XVIII la Corona española envió expedicionarios a reconocer el norte de la Patagonia, un territorio dominado por grupos indígenas pero de importancia estratégica para los hispanocriollos. Los funcionarios del Virreinato del Río de la Plata que llevaron a cabo dichas exploraciones registraron sus impresiones en diarios de viaje que analizamos con el objetivo de examinar los modos en que el paisaje norpatagónico fue construido simbólicamente. Consideramos que dicho paisaje se constituyó en base a las luchas desplegadas tanto por hispanocriollos como por indígenas buscando dar sentido al territorio. Sostenemos que, en este contexto, los personajes que se desempeñaban como intérpretes ejercían un rol fundamental en la configuración del territorio, dada la ambigüedad de su posición de intermediarios en las relaciones interétnicas.By late eighteen century the Spanish Crown sent expedition to recognize north Patagonia, a territory dominated by indigenous groups but also of strategic importance to the Hispanic-Creole population. River Plate Viceroyalty officials in charge of the above-mentioned explorations registered their impressions in travel diaries that are thoroughly analyzed in order to discover the ways this landscape of north Patagonia was symbolically constructed. We think this mestizo landscape was the result of struggles maintained between Hispanic-Creoles and natives searching to convey meaning to the territory. Moreover, we state that in this context, the actors who served as interpreters developed a key role in the territorial configuration, given the ambiguity of their position as intermediaries of interethnic relations.
In-vitro evaluation of the effect of canal curvature on adaptation of gutta-percha in canals obturated with HEROfill system by CBCT

International Nuclear Information System (INIS)

Zarei, M.; Talati, A.; Mortazavi, M.; Zarch, H.H.; Javidi, M.; Bidokhty, H.A.

2011-01-01

A hermetic seal of the root canal space following canal preparation is important in endodontics. This study evaluated the effect of canal curve on adaptation of gutta-percha to dentinal walls of canals obturated using the Herofill system. For this in vitro study, 80 mesial roots of mature human first molars with length of 16 mm, curve between 5 deg and 45 deg, and no caries or resorption of the root surface were selected. A cone beam computed tomography system was used to evaluate the presence or absence of a gap in the samples. Photographs were taken in three sections: 2 mm above the curve, at the curve and 2 mm below the curve. The gap area was identified using Photoshop and AutoCAD software. Kruskal Wallis and Mann-Whitney tests were used to analyze the data mounted in a castcurve. There were significant differences between the two lateral condensation groups with various curves; roots with more curve had more gaps. When the Herofill and lateral condensation groups were compared without considering the sections and curve, there was a significant difference between these groups and the Herofill group had less gaps. The Herofill system is an alternative to the lateral condensation technique in severely curved canals. (author)
Modelling Soil Carbon Content in South Patagonia and Evaluating Changes According to Climate, Vegetation, Desertification and Grazing

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Pablo Luis Peri

2018-02-01

Full Text Available In Southern Patagonia, a long-term monitoring network has been established to assess bio-indicators as an early warning of environmental changes due to climate change and human activities. Soil organic carbon (SOC content in rangelands provides a range of important ecosystem services and supports the capacity of the land to sustain plant and animal productivity. The objectives in this study were to model SOC (30 cm stocks at a regional scale using climatic, topographic and vegetation variables, and to establish a baseline that can be used as an indicator of rangeland condition. For modelling, we used a stepwise multiple regression to identify variables that explain SOC variation at the landscape scale. With the SOC model, we obtained a SOC map for the entire Santa Cruz province, where the variables derived from the multiple linear regression models were integrated into a geographic information system (GIS. SOC stock to 30 cm ranged from 1.38 to 32.63 kg C m−2. The fitted model explained 76.4% of SOC variation using as independent variables isothermality, precipitation seasonality and vegetation cover expressed as a normalized difference vegetation index. The SOC map discriminated in three categories (low, medium, high determined patterns among environmental and land use variables. For example, SOC decreased with desertification due to erosion processes. The understanding and mapping of SOC in Patagonia contributes as a bridge across main issues such as climate change, desertification and biodiversity conservation.
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Lifescience Database Archive (English)

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Lifescience Database Archive (English)

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File list: Oth.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Oth.CDV.50.AllAg.Atrioventicular_canals mm9 TFs and others Cardiovascular Atrioventicular canals... SRX1271841 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.CDV.50.AllAg.Atrioventicular_canals.bed ...
Presence of Arctotherium (Carnivora, Ursidae, Tremarctinae in a pre-cultural level of Baño Nuevo-1 cave (Central Patagonia, Chile

Directory of Open Access Journals (Sweden)

López Mendoza, P.

2015-12-01

Full Text Available The description of an I3 assigned to Arctotherium sp. obtained from the Baño Nuevo-1 site (Central Patagonia, Chile is presented. The finding was recovered from Layer 5 and it is associated to Macrauchenia sp., Lama guanicoe, Felidae, Camelidae, Equidae and Mylodontidae, within a sterile deposit of cultural material, dated between ca. 13.500 and 11.200 BP. Despite the fact that it is only a single specimen, such finding extends the known distribution for the genus in Chile.Se presenta la descripción de un I3 asignado a Arctotherium sp. proveniente del sitio Baño Nuevo-1 (Patagonia Central, Chile. El hallazgo fue realizado en la Capa 5 y está asociado a restos de Macrauchenia sp., Lama guanicoe, Felidae, Camelidae, Equidae y Mylodontidae dentro de un depósito estéril de material cultural, datado entre los ca. 13.500 y 11.200 años AP. Aunque se trata de un único espécimen, amplía el rango de distribución conocido para este género en Chile.

First branchial cleft fistula associated with external auditory canal stenosis and middle ear cholesteatoma.

Science.gov (United States)

Abdollahi Fakhim, Shahin; Naderpoor, Masoud; Mousaviagdas, Mehrnoosh

2014-10-01

First branchial cleft anomalies manifest with duplication of the external auditory canal. This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.
Tullio phenomenon in superior semicircular canal dehiscence syndrome.

Science.gov (United States)

Basura, Gregory J; Cronin, Scott J; Heidenreich, Katherine D

2014-03-18

Tullio phenomenon refers to eye movements induced by sound.(1) This unusual examination finding may be seen in superior semicircular canal dehiscence (SSCD) syndrome.(2) This disorder is due to absent bone over the superior semicircular canal (figure). Patients complain of dizziness triggered by loud sound, aural fullness, autophony, and pulsatile tinnitus. When Tullio phenomenon exists in SSCD syndrome, the patient develops a mixed vertical-torsional nystagmus in which the slow phase rotates up and away from the affected ear (video on the Neurology® Web site at Neurology.org). This pattern of nystagmus aligns in the plane of the dehiscent semicircular canal and is due to excitation of its afferent nerves.
Qualitative analysis of the Dix-Hallpike maneuver in multi-canal BPPV using a biomechanical model: Introduction of an expanded Dix-Hallpike maneuver for enhanced diagnosis of multi-canal BPPV

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Henri Traboulsi

2017-09-01

Conclusion: The Dix–Hallpike maneuver may cause simultaneous movement of otoliths present in multiple canals and create an obstacle to accurate diagnosis in multi-canal BPPV. An expanded Dix-Hallpike maneuver is described which adds intermediate steps with the head positioned to the right and left in the horizontal position before head-hanging. This expanded maneuver has helped to isolate affected semi-circular canals for individual assessment in multiple canal BPPV.
Management of foreign object in the root canal of central incisor tooth

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Mothanna Alrahabi

2014-01-01

Full Text Available There are several reports describing the impaction of foreign objects into the exposed pulp chambers and canals by patients, especially children as they often have the habit of inserting foreign objects in the oral cavity. These objects will become a potent source of infection.This case report describes the retrieval of a foreign object impacted into the root canal of a 12-year-old male patient who was referred to the endodontic specialty clinic at Taibah University College of Dentistry. The patient′s chief complaint was a pain in the upper left central tooth. Clinical examination revealed a complicated enamel-dentin fracture with a large caries cavity. A periapical radiographic image showed a radiopaque object in the root canal system. Stainless steel Hedstrom files were used to retrieve the object from the canal. Following a proper cleaning and shaping of the root canal system, an intra-canal calcium hydroxide dressing was placed for 1 week. The root canal system was then filled with sealer and gutta-percha using the lateral compaction technique and the tooth received an aesthetic restoration.
Effectiveness of EDTA as the irrigation solution to remove smear layer in root canal

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Kurniasri Amas Achiar

2009-07-01

Full Text Available One of the objectives of successful endodontic treatment is the hermetic obturation of the root canal system. To achieve this, the root canal filling must seal the canal space both apically and coronally to prevent the ingress of microorganisms or tissue fluids into the canal space. Apical leakage is reported a common reason for the clinical failure of endodontic therapy. Leakage through an obturated root canal is expected to take place at interfaces between sealer and dentin or sealer and gutta-percha, or through voids within the sealer. Hence, the sealing quality of root canal filling depends much on the sealing ability of the sealer. Therefore, anything that may influence the adaptation of the root filling to the canal wall is can determine the degree and the extent of leakage, and ultimately the prognosis of the endodontic therapy. In endodontic therapy, the smear layer formation results from root canal preparation and may influence the effective seal of the root canal system. The smear layer formation is mainly composed of inorganic components (dentin debris and organic materials, such as pulp tissue remnant, bacteria, and blood cells. Removal of the smear layer from the root canal walls before the obturation can reduce the leakage of root canal sealer. To remove the smear layer use 10 ml 17% EDTA followed by 10 ml of 5.25% NaOCl as irrigating solution. This paper discribe about how the effectivity of EDTA as irigating solution to remove the smear layer especially in the apical root canal with many lateral canal to reduce the apical leakage.
Magnetic resonance imaging anatomy of the anal canal

International Nuclear Information System (INIS)

Kashyap, P.; Bates, N.

2004-01-01

The anatomy of the anal canal is complex but well demonstrated by MRI. Understanding the anatomy is a prerequisite for determining the true site and the extent of pathology, especially for surgical workup. In this article, the MRI anatomy of the anal canal has been displayed using highlighted MRI images and line diagrams. Copyright (2004) Blackwell Science Pty Ltd
Nodular Fasciitis of External Auditory Canal

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Jihyun Ahn

2016-09-01

Full Text Available Nodular fasciitis is a pseudosarcomatous reactive process composed of fibroblasts and myofibroblasts, and it is most common in the upper extremities. Nodular fasciitis of the external auditory canal is rare. To the best of our knowledge, less than 20 cases have been reported to date. We present a case of nodular fasciitis arising in the cartilaginous part of the external auditory canal. A 19-year-old man complained of an auricular mass with pruritus. Computed tomography showed a 1.7 cm sized soft tissue mass in the right external auditory canal, and total excision was performed. Histologic examination revealed spindle or stellate cells proliferation in a fascicular and storiform pattern. Lymphoid cells and erythrocytes were intermixed with tumor cells. The stroma was myxoid to hyalinized with a few microcysts. The tumor cells were immunoreactive for smooth muscle actin, but not for desmin, caldesmon, CD34, S-100, anaplastic lymphoma kinase, and cytokeratin. The patient has been doing well during the 1 year follow-up period.
Incisive canal deflation for correct implant placement: case report.

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Spin-Neto, Rubens; Bedran, Telma Blanca Lombardo; de Paula, Wagner Nunes; de Freitas, Rubens Moreno; de Oliveira Ramalho, Lizeti Toledo; Marcantonio, Elcio

2009-12-01

This article is a case report of a patient in whom the prosthetic planning indicated the necessity of an incisive canal deflation for the correct installation of an implant that is to be osseointegrated. In the reopening phase after the bone graft installation, the incisive canal deflation (biopsy of its content) was done and titanium implants were installed with one of them invading the anatomical space occupied previously by the incisive canal. The biopsy analysis showed fragments of the incisive artery and nerve, which are responsible for the anterior upper-tooth pulp, the periodontium vascularization and the innervation. From the anastomosis present along with other structures allied with the absence of teeth in the region, there was no detriment to the patient caused by the deflation. Incisive canal deflation is a viable technique in implantology. It can permit ideal prosthetic planning with no detriment to the patient.
First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

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Abdollahi fakhim, Shahin; Naderpoor, Masoud; Mousaviagdas, Mehrnoosh

2014-01-01

Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal. Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. Conclusion: It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear. PMID:25320705
First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

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shahin abdollahi fakhim

2014-10-01

Full Text Available Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal. Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. Conclusion: It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.
Experimental circumferential canaloplasty with a new Schlemm canal microcatheter

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Mao-Song Xie

2018-01-01

Full Text Available AIM: To present a new, simple, inexpensive Schlemm canal microcatheter for circumferential canaloplasty in a rabbit model. METHODS: A rabbit glaucoma animal model was established by intravitreal injection of triamcinolone acetonide. Circumferential canaloplasty with a new Schlemm canal microcatheter (patent license number: 201220029850.0 was performed. The Schlemm canal microcatheter was composed of microcatheter wall and lumen. The wall was made of high refractive index plastic optical fiber that could be attached to an illuminant so that the whole lighted microcatheter was visible during circumferential canaloplasty. The lumen could be attached to an injector for injection of viscoelastic during catheterization. Rabbits were divided randomly into the control, model and treatment groups. Intraocular pressure (IOP was measured with a Tono-pen tonometer pre-operation and 3, 7, 14, 21 and 28d post-operation. Ultrasound biomicroscopy was performed to visualize the Schlemm canal microcatheter in the Schlemm canal and the sclera pool. RESULTS: The Schlemm canal microcatheter could be used to perform circumferential canaloplasty in the rabbit glaucoma animal model. IOP was lower in the treatment group than that in the model group 3, 7, 14 and 28d after operation. There were no significant differences in IOP between the control group and treatment group. The differences among the three groups were statistically significant (3d: F=41.985, P<0.001; 7d: F=65.696, P<0.001; 14d: F=114.599, P<0.001; 28d: F=55.006, P<0.001. CONCLUSION: Circumferential canaloplasty is safe and effective in control of experimental glaucoma model in rabbits.
Roentgenographic study of the mandibular canal

International Nuclear Information System (INIS)

Ahn, Hyung Kyu

1980-01-01

The mandibular canal must be considered carefully during the surgical treatment, especially surgical extraction of the impacted tooth and intraosseous implant, because it contains the important inferior alveolar nerve and vessels. The author investigated the curvature of the mandibular canal and its relation to the mandibular molars and positional relation between the mental foramen and the mandibular premolars in orthopantomogram. The materials consisted of 441 orthopantomograms divided four groups; Group I consisted of 56 males and 44 females from 1 to 6 years of age, Group II consisted of 58 males and 45 females from 7 to 12 years of age, Group III consisted of 65 males and 33 females from 13 to 18 years of age, Group IV consisted of 86 males and 54 females over 19 years of age. The results were as followings; 1. The curvature of mandibular canal was 144.50 .deg. in Group II, 148.11 .deg. in Group III, 147.33 .deg. in Group IV. 2. The curvature of mandibular canal was located most frequently on the area between mandibular 1st molar and mandibular 2nd molar in Group I (42%) and on the mandibular 2nd molar area in Group II (54%), Group III (59%), Group IV (53%). 3. The position of mental foramen was most frequently below the mandibular 1st premolar in Group I (58%), between the mandibular 1st premolar and the 2nd premolar in Group II (62%), Group III (47%), and below the mandibular 2nd premolar in Group IV (58%).
Root anatomy and canal configuration of the permanent mandibular first molar: a systematic review.

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de Pablo, Oliver Valencia; Estevez, Roberto; Péix Sánchez, Manuel; Heilborn, Carlos; Cohenca, Nestor

2010-12-01

The main goal of endodontic therapy is to prevent or heal apical periodontitis. However, root canal anatomy might present a clinical challenge directly related to the treatment outcome. The purpose of this study was to review published literature related to root anatomy and root canal configuration of the permanent mandibular first molar. An exhaustive search was undertaken to identify published literature related to the root anatomy and root canal morphology of the permanent mandibular first molar by using key words. The search of the MEDLINE database included all publications from 1966-May 2010. Selected articles were then obtained and reviewed. Data evaluated and summarized in the data sheet included methodology, population, number of teeth per study (power), number of root canals, type of root canal configuration, and identification of number of apical foramina. Forty-one studies were identified including a total of 18,781 teeth. The incidence of a third root was 13% and was strongly correlated with the ethnicity of the studied population. Three canals were present in 61.3%, 4 canals in 35.7%, and 5 canals in approximately 1%. Root canal configuration of the mesial root revealed 2 canals in 94.4% and 3 canals in 2.3%. The most common canal system configuration was Vertucci type IV (52.3%), followed by type II (35%). Root canal configuration of the distal root revealed type I configuration in 62.7%, followed by types II (14.5%) and IV (12.4%). The presence of isthmus communications averaged 54.8% on the mesial and 20.2% on the distal root. The number of roots on the mandibular first molar is directly related to ethnicity. Root canal morphology and configuration might present the clinician with a complex anatomy requiring more diagnostic approaches, access modifications, and clinical skills to successfully localize, negotiate, disinfect, and seal the root canal system. Crown Copyright © 2010. Published by Elsevier Inc. All rights reserved.
Unusual root canal morphology of mandibular second premolars: A case series and review

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Snehal Sonarkar

2017-01-01

Full Text Available Mandibular second premolars (MSPs have varied anatomy ranging from 1 to 3 roots and 1–5 canals. Successful endodontic treatment is achieved by proper access opening, cleaning, and shaping and three-dimensional obturation. This case series describes five cases in which MSPs have been diagnosed with aberrant canal system. The Case 1 and 5 has one root with Vertucci's Type V canal configuration. The Case 2 has two roots with two canals, the Case 3 has one root with Vertucci's Type IV canal configuration, whereas the Case 4 has three roots with three canals. This case series also describes a classification for describing the root configuration. The clinical implications of this paper are first to reach at appropriate diagnosis of canal system using diagnostic aids (angulated radiographs and dental operating microscope. Second, to use advanced endodontic instruments for achieving successful endodontic therapy (NiTi rotary instruments.
Root Canal Configuration of Maxillary First Permanent Molars in an Iranian Population

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Saeed Rahimi

2007-06-01

Full Text Available
Background and aims. It is critical to have a proper knowledge of the normal anatomy of the pulp and its variations for the success of endodontic treatment. The purpose of this study was to investigate variations in the root canal system of maxillary first permanent molars in an Iranian population.
Materials and methods. In this study, 137 maxillary first molars were decalcified, dye-injected, cleared and studied.
Results. The results demonstrated that 37.96% of the maxillary first molars under study had three canals, 58.4% had four canals and 3.64% had five canals.
Conclusion. According to the results of this study and considering variations in the root canal systems of maxillary first molars, it seems that great care should be taken in the root canal treatment of these teeth.
Anatomy and morphology of the nasopalatine canal using cone-beam computed tomography

International Nuclear Information System (INIS)

Thakur, Arpita Rai; Burde, Krishna; Guttai, Kruthika; Naikmasu, Venkatesh

2013-01-01

This study was performed to evaluate the general anatomy and morphology of the nasopalatine canal using cone-beam computed tomography (CBCT) and to determine the human anatomic variability of the nasopalatine canal in relation to age and gender. The study included 100 subjects aged between 20 and 86 years who were divided into the following 3 groups: 1) 20-34 years old; 2) 35-49 years old; 3) ≥50 years old. The subjects were equally distributed between the genders. CBCT was performed using a standard exposure and patient positioning protocol. The data of the CBCT images were sliced in three dimensions. Image planes on the three axes (X, Y, and Z) were sequentially analyzed for the location, morphology and dimensions of the nasopalatine canal by two independent observers. The correlation of age and gender with all the variables was evaluated. The present study did not reveal statistically significant differences in the number of openings at the nasal fossa; diameter of the nasal fossa openings; diameter of the incisive fossa; shape, curvature, and angulation of the canal as viewed in the sagittal sections; antero-posterior dimensions and length of the canal in the sagittal sections; or the level of division of the canal in the coronal plane by age. However, males and females showed significant differences in the length of the canal in the sagittal sections and level of the division of the canal in the coronal plane. The present study highlighted important variability observed in the anatomy and morphology of the nasopalatine canal.
Anatomy and morphology of the nasopalatine canal using cone-beam computed tomography

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Thakur, Arpita Rai [Dept. of Oral Medicine and Radiology, Faculty of Dentistry, Jamia Millia Islamia University, New Delhi (India); Burde, Krishna; Guttai, Kruthika; Naikmasu, Venkatesh [Dept. of Oral Medicine and Radiology, S.D.M. College of Dental Sciences and Hospital, Dharwad (India)

2013-12-15

This study was performed to evaluate the general anatomy and morphology of the nasopalatine canal using cone-beam computed tomography (CBCT) and to determine the human anatomic variability of the nasopalatine canal in relation to age and gender. The study included 100 subjects aged between 20 and 86 years who were divided into the following 3 groups: 1) 20-34 years old; 2) 35-49 years old; 3) ≥50 years old. The subjects were equally distributed between the genders. CBCT was performed using a standard exposure and patient positioning protocol. The data of the CBCT images were sliced in three dimensions. Image planes on the three axes (X, Y, and Z) were sequentially analyzed for the location, morphology and dimensions of the nasopalatine canal by two independent observers. The correlation of age and gender with all the variables was evaluated. The present study did not reveal statistically significant differences in the number of openings at the nasal fossa; diameter of the nasal fossa openings; diameter of the incisive fossa; shape, curvature, and angulation of the canal as viewed in the sagittal sections; antero-posterior dimensions and length of the canal in the sagittal sections; or the level of division of the canal in the coronal plane by age. However, males and females showed significant differences in the length of the canal in the sagittal sections and level of the division of the canal in the coronal plane. The present study highlighted important variability observed in the anatomy and morphology of the nasopalatine canal.
Anomalous facial nerve canal with cochlear malformations.

Science.gov (United States)

Romo, L V; Curtin, H D

2001-05-01

Anteromedial "migration" of the first segment of the facial nerve canal has been previously identified in a patient with a non-Mondini-type cochlear malformation. In this study, several patients with the same facial nerve canal anomaly were reviewed to assess for the association and type of cochlear malformation. CT scans of the temporal bone of 15 patients with anteromedial migration of the first segment of the facial nerve canal were collected from routine departmental examinations. In seven patients, the anomalous course was bilateral, for a total of 22 cases. The migration was graded relative to normal as either mild/moderate or pronounced. The cochlea in each of these cases was examined for the presence and size of the basilar, second, and apical turns. The turns were either absent, small, normal, or enlarged. The CT scans of five patients with eight Mondini malformations were examined for comparison. The degree of the facial nerve migration was pronounced in nine cases and mild/moderate in 13. All 22 of these cases had associated cochlear abnormalities of the non-Mondini variety. These included common cavity anomalies with lack of definition between the cochlea and vestibule (five cases), cochleae with enlarged basilar turns and absent second or third turns (five cases), and cochleae with small or normal basilar turns with small or absent second or third turns (12 cases). None of the patients with Mondini-type cochlear malformations had anteromedial migration of the facial nerve canal. Anteromedial migration of the facial nerve canal occurs in association with some cochlear malformations. It did not occur in association with the Mondini malformations. A cochlea with a Mondini malformation, being similar in size to a normal cochlea, may physically prohibit such a deviation in course.
Comparative Study of Three Rotary Instruments for root canal Preparation using Computed Tomography

International Nuclear Information System (INIS)

Mohamed, A.M.E.

2015-01-01

Cleaning and shaping the root canal is a key to success in root canal treatment. This includes the removal of organic substrate from the root canal system by chemo mechanical methods, and the shaping of the root canal system into a continuously tapered preparation. This should be done while maintaining the original path of the root canal. Although instruments for root canal preparation have been progressively developed and optimized, a complete mechanical debridement of the root canal system is rarely achievable. One of the main reasons is the geometrical dis symmetry between the root canal and preparation instruments. Rotary instruments regardless of their type and form produce a preparation with a round outline if they are used in a simple linear filing motion, which in most of the cases do not coincide with the outline of the root canal. Root canal preparation in narrow, curved canals is a challenge even for experienced endodontists. Shaping of curved canals became more effective after the introduction of nickel-titanium (Ni-Ti) endodontic instruments. Despite the advantages of Ni-Ti rotary instruments, intra canal fracture is the most common procedural accident that occurs with these instruments during clinical use. It is a common experience between clinicians that Ni-Ti rotary instruments may undergo unexpected fracture without any visible warning, such as any previous permanent defect or deformation. Pro Taper Ni-Ti instruments were introduced with a unique design of variable taper within one instrument and continuously changing helical angles. Pro Taper rotary instruments are claimed to generate lower torque values during their use because of their modified nonradial landed cross-section that increases the cutting efficiency and reduces contact areas. On the other hand, the variable taper within one instrument is believed to reduce the ‘taper lock’ effect (torsional failure) in comparison with similarly tapered instruments. Nevertheless, Pro Taper
[Shaping ability of two nickel-titanium rotary systems in simulated S-shaped canals].

Science.gov (United States)

Luo, Hong-xia; Huang, Ding-ming; Zhang, Fu-hua; Tan, Hong; Zhou, Xue-dong

2008-01-01

To evaluate the shaping ability of two nickel-titanium rotary systems (ProTaper and Hero642) in simulated S-shaped canals. Thirty simulated S-shaped canals were randomly divided into three groups and prepared by ProTaper, Hero642, ProTaper combined with Hero642 respectively. All the canals were scanned before and after instrumentation, and the amount of material removed in the inner and outer wall and the canal width after instrumentation were measured with a computer image analysis program. There was significant difference in the amount of material removed at the inner side of apical curvature and outer side of apex between ProTaper combined with Hero642 and ProTaper files (P Hero642, and the taper of canals were better than those prepared by Hero642. ProTaper combined with Hero 642 had better shaping ability to maintain the original shape and could create good taper canals in the simulated S-shaped canal model.

Pollution of Lahore canal water in the city premises

International Nuclear Information System (INIS)

Hussain, Z.; Baig, M.A.

1997-01-01

Water contamination is one of the major environmental pollution problems facing Pakistan because it has a direct impact on the health of human beings and crops. Lahore Canal water is being used both for irrigation and a source of ground water recharge. For the best use of this water, extent of pollution and its effect on soil hydraulic properties needs to be studied. For this purpose, water samples from twenty three sites and soil samples from three sites were collected along the Canal within the city limits of Lahore. The survey of the area from Jallo Park to Mall Road, show that all the abadies/colonies and industries situated on both sides of the canal dump their waste water and garbage in to canal. This result in increase of salinity as well as BOD and COD values which were found maximum at the locations of Herbuns Pura, Mughal Pura Dharam Pura, and Thoker Niaz Baig. (authors)
CT of the external auditory canal: Correlation with clinical otoscopy

International Nuclear Information System (INIS)

Shankar, L.; Hawke, M.; Leekam, R.N.

1987-01-01

CT is the modality of choice in the assessment of external auditory canal abnormalities. Disorders of the complex structures within the ear that may be difficult to define clinically are well visualized on high-resolution CT. This exhibit illustrates various external auditory canal abnormalities and correlates these with color illustrations from clinical otoscopy. Congenital lesions of the external auditory canal - microtia, temporo-bandibular joint herniation, and fistulas - and various acquired lesions - traumatic, inflammatory, and neoplastic - are reviewed in this exhibit
Insectos acuáticos de la Meseta del Somuncura, Patagonia, Argentina. Inventario preliminar

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Javier MUZÓN

2005-01-01

Full Text Available Se brinda un inventario preliminar de los insectos acuáticos de la Meseta del Somuncura y su área de influencia (Patagonia, Argentina realizado sobre la base de colecciones y registros previos de especies pertenecientes a los órdenes Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (familias Ceratopogonidae, Culicidae y Psychodidae y Coleoptera. Se han relevado diversos tipos de ambientes en 14 localidades. El número de especies registrado asciende a 78, agrupadas en 51 géneros y 26 familias, de las cuales 33 se citan por primera vez del área. De los taxa registrados 83% de los géneros corresponden a grupos de amplia distribución (neotropicales, americanos o cosmopolitas, mientras que 41% de las especies presentan una distribución patagónica o andina.
Toxocariasis in Carnivora from Argentinean Patagonia: Species molecular identification, hosts, and geographical distribution

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R.M. Vega

2018-04-01

Full Text Available Twenty four specimens of seven species belonging to the families Felidae, Mustelidae, and Canidae were obtained in Lanín and Nahuel Huapi National Parks from March 1996 to April 2016. Specimens were processed by necropsy in order to contribute to the knowledge of toxocariasis in wild carnivores of Argentinean Patagonia. The only Puma concolor and the seven Leopardus geoffroyi were positive for Toxocara cati. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP of the ITS-1 region from larval and adult DNA was carried out to confirm parasite species identification. This is the first molecular determination of T. cati from wild felids in Argentina and the study also fill gaps about the spatial distribution and hosts for Toxocara cati. Keywords: Toxocara cati, Puma concolor, Leopardus geoffroyi, Molecular identification, Argentina
Incidence of two canals in extracted mandibular incisors teeth of Saudi Arabian samples

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Khalid S Al-Fouzan

2012-01-01

Full Text Available Aim: The purpose of this in vitro study is to provide clinical data on the presence of the second canal in mandibular incisor teeth of Saudi Arabian Samples. Materials and Methods: Eighty extracted human mandibular incisors were collected from Saudi patients. The teeth were accessed by small round bur then placed in 5.25% sodium hypochlorite for 24 hours to dissolve the organic debris. Indian ink was injected inside the root canal systems under negative pressure. The teeth were decalcified in 5% nitric acid for three days then dehydrated in different concentrations of ethyl alcohol. Following the decalcification process, the teeth were cleared in methyl salicylate and evaluated according to Vertucci′s classification. Result: Fifty six of both mandibular central and lateral incisor teeth (70% had type I canal configuration (one main canal and one main apical foramen, while the remaining 30% of the sample (24 teeth had a type III canal configuration (two separate canals and merged into one canal before exiting the tooth through single apical foramen. Conclusion : The incidence of two canals in mandibular incisor teeth is about one third of the examined Saudi Arabian samples with no difference between the centrals and laterals. The clinician should deal with these teeth as if they have two canals unless it is proved otherwise.
AFSC/ABL: Lynn Canal Echo-Integrated Trawl Surveys, 2001-2004

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National Oceanic and Atmospheric Administration, Department of Commerce — The acoustic trawl database for Lynn Canals echo-trawl survey was conducted from 2001 to 2004 throughout southern Lynn Canal in southeast Alaska. Acoustic surveys...
EL TRANSPORTE DE CANTIDAD DE MOVIMIENTO EN CANALES

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Francisco Jaime Mejía

Full Text Available Este artículo tiene por objeto aplicar el transporte de cantidad de movimiento al flujo en canales como una metodología independiente de otros principios físicos. Así se subsana una carencia de la literatura técnica cuando aborda la interpretación adicional de fenómenos hidráulicos que habitualmente se tratan desde la conservación de la energía. Concluye acerca del comportamiento de la profundidad de flujo en un canal ante diversas condiciones de flujo o variaciones de la profundidad o en presencia de controles hidráulicos. Con la ayuda de la ecuación de transporte de cantidad de movimiento a lo largo de un canal se interpreta el comportamiento del tirante hidráulico en flujo uniforme, en flujo no uniforme con variación gradual y en algunos fenómenos locales de flujo rápidamente variado como ocurre en las transiciones y en el resalto hidráulico. Se obtienen las ecuaciones del resalto hidráulico para calcular la profundidad inicial y secuente, conocida una de las dos, en diversas secciones transversales del canal.
Treatment of Two Canals in All Mandibular Incisor Teeth in the Same Patient

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Vandana B. Kokane

2014-01-01

Full Text Available The main reason for unfavourable outcome in endodontic treatment of mandibular incisor is the inability to detect the presence of second canal. Pain even after extirpation of complete pulp tissue from root canal of vital teeth is the main indication of hidden canals. The present case report is also on pain because of another neglected canal in all mandibular incisors in the same patient.
Extracting Environmental Benefits from a New Canal in Nicaragua: Lessons from Panama.

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Richard Condit

2015-07-01

Full Text Available Biologists have raised objections to a new canal in Nicaragua, but in this Essay I argue that dire predictions of environmental catastrophe are exaggerated. I present an alternative view based on my research experience in Panama, where Canal operations foster forest conservation. Currently in Nicaragua, the rate of forest loss is so rapid that the canal cannot make it worse. Rather, I contend, adoption of international standards in canal construction could lead to net environmental and social benefits for the country.
Continuous Adductor Canal Blocks

DEFF Research Database (Denmark)

Monahan, Amanda M; Sztain, Jacklynn F; Khatibi, Bahareh

2016-01-01

on cutaneous knee sensation in volunteers. METHODS: Bilateral adductor canal catheters were inserted in 24 volunteers followed by ropivacaine 0.2% administration for 8 hours. One limb of each subject was assigned randomly to a continuous infusion (8 mL/h) or automated hourly boluses (8 m...
The width of the incisive canal and labial alveolar bone of the incisive canal: an assessment on CT images

International Nuclear Information System (INIS)

Roh, Yang Gyun; Jang, Hyun Seon; Kim, Byung Ock; Kim, Jin Soo

2006-01-01

To assess the width of the labial alveolar bone of the incisive canal and the width of the incisive canal on spiral computed tomographic images of the anterior portion of the maxilla. Study materials included 38 CT scans taken for preoperative planning of implant placement. Axial cross-sectioned image entirely showing the incisive canal at an orifice to the oral cavity, middle portion, and an orifice to the nasal cavity and the diameter of the incisive canal at the middle portion were determined by two specialist using Digora for Windows 2.1. The statistical analyses were carried out using SPSS 12.0.1. When the maxillary central incisors remained, the mean labial alveolar bone width were 6.81±1.41 mm, 6.46±1.33 mm, and 7.91±1.33 mm. When the maxillary central incisors were missed the mean width were 5.42±2.20 mm, 6.23±2.29 mm, and 7.89±2.13 mm. The labial alveolar bone width at middle portion and an orifice to the nasal cavity were of no statistical significant difference according to presence of the maxillary central incisors (P>0.05). The width between oral cavity and nasal cavity, middle portion and to masal cavity revealed statistically significant difference (P<0.05)
[Shaping ability of multi-taper nickel-titanium files in simulated resin curved root canal].

Science.gov (United States)

Luo, Hong-Xia; Huang, Ding-Ming; Jia, Liu-He; Luo, Shi-Gao; Gao, Xiao-Jie; Tan, Hong; Zhou, Xue-Dong

2006-08-01

To compare the shaping ability of ISO standard stainless steel K files and multi-taper ProTaper nickel-titanium files in simulated resin curved root canals. METHODS Thirty simulated resin root canals were randomly divided into three groups and prepared by stainless steel K files, hand ProTaper, rotary ProTaper, respectively. The amount of material removed from inner and outer wall and canal width after canal preparation was measured, while the canal curvature before and after canal preparation and canals aberrations were recorded. The stainless steel K files removed more material than hand ProTaper and rotary ProTaper at the outer side of apex and inner side of curvature (P ProTaper group (P ProTaper had no evident aberration. The shaping ability of ProTaper is better than stainless steel K files.
An experimental study on the computed tomography of the cervical spinal canal

International Nuclear Information System (INIS)

Wakabayashi, Tsuguru

1980-01-01

A study was carried out to investigate how accurately CT could delineate the vertebral canal, vertebral body, lamina, intervertebral foramen and transverse process, and which factor influences the size of the vertebral canal, using cervical vertebrae obtained from four cadavers and one skeleton. EMI CT 5005 scanner was used. CT picture depicted accurate shapes of the vertebral canal, body and transverse process. The sagittal diameter of the vertebral canal of CT picture varied by various conditions, such as difference of scanning chance, scanning angle, window width and level, but variations due to different absorption coefficients of the bone surrounding the vertebral canal were negligible. It was most significantly changed by scanning angle. Permissible scanning angle was within 5 0 , and morphological findings were not influenced up to 15 0 . The size of the vertebral canal was most accurately measured under the condition of 400 in width and 250 in level. The optimal condition for delineation of the spine seemed to be 400 in width and 100 - 150 in level. Under the condition at width 400 and level 100, the vertebral canal was delineated narrower by an average 0.6 mm and 0.2 mm in the sagittal and transverse diameter respectively. In CT picture of the imitational ossified posterior Longitudinal ligament made of plastic and alginate, the average narrowing rate of the vertebral canal was 4.4% greater than the one obtained by lateral view of radiograph, but both correlated well with each other. The narrowing rate of the vertebral canal by CT tended to increase in proportion to the increase in scanning angle. (J.P.N.)
Root canal debris removal using different irrigating needles: An SEM study

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Sheetal Ghivari

2011-01-01

Full Text Available Aim: This study was carried out to compare the efficacy of three irrigating needle designs in removal of debris from different parts of the root canal. Materials and Methods: Thirty human maxillary canines were prepared using HERO Shaper rotary system and irrigated with 1 ml of 5.25% sodium hypochlorite (NaOCl after each instrument change. Three 25-gauge irrigation needle designs - brush-covered Navi Tip FX (Group I, side-vented needle RC Twents (Group II and single-beveled (Group III irrigating needles - were tested for their efficiency in debris removal in three different parts of the root canal (n=10 canals per group. Following instrumentation, the roots were vertically sectioned and divided into coronal, middle and apical thirds for observation under scanning electron microscope (×200 magnification. Debris on the canal wall was evaluated by using a four-scale scoring system described by Paque and his co-workers. Results: The canals irrigated with brush-covered needle Navi Tip FX (Group I showed lower average debris score, indicating greater removal of debris in coronal third as compared to middle and apical thirds, whereas the canals irrigated with side-vented needle (Group II and single-beveled needle (Group III exhibited lower average score in the middle third than coronal and apical thirds. All the three needle designs exhibited higher debris score in apical third of the root canal. Tukey multiple comparisons test was applied at a significance level of P>0.05. A statistically significant difference (P<0.05 was observed in the debris removal in the coronal and middle thirds of root canals irrigated with brush-covered Navi Tip FX (Group I and side-vented (Group II needles, respectively, when compared with other needle design groups. Conclusion: Within the limitations of this study, it can be concluded that all the needle designs tested were effective in certain regions of the root canal with apical third uncleaned. Side-vented needle by
Estresse crônico melhora a função miocárdica sem alterar a atividade do canal-L para Ca+2 em ratos

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Thiago Bruder-Nascimento

2012-10-01

Full Text Available FUNDAMENTO: O estresse crônico está associado à remodelação cardíaca; entretanto, os mecanismos permanecem a ser descobertos. OBJETIVO: A proposta deste estudo foi testar a hipótese de que o estresse crônico promove disfunção cardíaca associada a depressão da atividade do canal-L para Ca2+. M MÉTODOS: Ratos Wistar machos com 30 dias de idade (70 - 100 g foram distribuídos dentro de dois grupos: controle (C e estresse crônico (St. O estresse consistiu na imobilização durante 15 semanas, cinco vezes por semana, 1 h por dia. A função cardíaca foi avaliada pela performance do ventrículo esquerdo por meio do ecocardiograma e pelo músculo papilar ventricular isolado. A função do músculo papilar foi avaliada em condição basal e com manobras inotrópicas, como: pós-pausa e elevação na concentração extracelular de Ca2+, na presença ou ausência de um bloqueador específico de canal-L para Ca2+. RESULTADOS: O estresse ficou caracterizado por hipertrofia das glândulas adrenais, aumento nos níveis de corticosterona circulante e por hipertensão arterial. Ainda, o estresse crônico gerou hipertrofia ventricular esquerda. O estresse crônico foi capaz de melhorar a resposta no músculo papilar para manobras inotrópicas positivas. A melhora de função não esteve associada com o canal-L para Ca2+. CONCLUSÃO: O estresse produziu hipertrofia cardíaca; entretanto, nos estudos de músculo papilar isolado, as manobras inotrópicas positivas potencializaram a função cardíaca em ratos estressados, sem o envolvimento do canal-L para Ca2+. Assim os mecanismos responsáveis permanecem incertos para alterações no influxo de Ca2+.
Spinal canal stenosis; Spinalkanalstenose

Energy Technology Data Exchange (ETDEWEB)

Papanagiotou, P.; Boutchakova, M. [Klinikum Bremen-Mitte/Bremen-Ost, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Bremen (Germany)

2014-11-15

Spinal stenosis is a narrowing of the spinal canal by a combination of bone and soft tissues, which can lead to mechanical compression of spinal nerve roots or the dural sac. The lumbal spinal compression of these nerve roots can be symptomatic, resulting in weakness, reflex alterations, gait disturbances, bowel or bladder dysfunction, motor and sensory changes, radicular pain or atypical leg pain and neurogenic claudication. The anatomical presence of spinal canal stenosis is confirmed radiologically with computerized tomography, myelography or magnetic resonance imaging and play a decisive role in optimal patient-oriented therapy decision-making. (orig.) [German] Die Spinalkanalstenose ist eine umschriebene, knoechern-ligamentaer bedingte Einengung des Spinalkanals, die zur Kompression der Nervenwurzeln oder des Duralsacks fuehren kann. Die lumbale Spinalkanalstenose manifestiert sich klinisch als Komplex aus Rueckenschmerzen sowie sensiblen und motorischen neurologischen Ausfaellen, die in der Regel belastungsabhaengig sind (Claudicatio spinalis). Die bildgebende Diagnostik mittels Magnetresonanztomographie, Computertomographie und Myelographie spielt eine entscheidende Rolle bei der optimalen patientenbezogenen Therapieentscheidung. (orig.)
Effects of irrigation solutions and Calcium hydroxide dressing on root canal treatments of periapical lesions

OpenAIRE

Nirmala, Vita

2006-01-01

The preparation of root canal in endodontic treatment plays an important role in treating non vital teeth with periapical lesion. Some factors influence the success of root canal treatment in short and long terms are the irrigation of root canal using antiseptic solution and the use of root canal medicament. The aim of this literature study is to determined the effect of irrigation solution and Calcium hydroxide dressing in root canal treatment of periapical lesions. The use of root canal med...
The Effects of NiTi Hand and Rotary Canal Master U and K-Flex Instrumentation of Root Canal Morphology

Science.gov (United States)

1992-09-01

Rotary Canal Master "U" and K-Flex Instrumentation of Root Canal Morphology 6. AUTHOR(S) Robert H. Haller 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES... endodontic failure. B. STATET OF THE PREL]2U Conventional endodontic instruments have re.nained basically unchanged since the introduction of the K-type...F;hcw"e that this nO𔃾 instruneent destim tended ti- produce rounder pr rMticns with • t!-rnnVortaticn than c rnvrnticnal 4 endodontic instruments
33 CFR 117.181 - Oakland Inner Harbor Tidal Canal.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Oakland Inner Harbor Tidal Canal. 117.181 Section 117.181 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Tidal Canal. The draws of the Alameda County highway drawbridges at Park Street, mile 5.2; Fruitvale...
File list: InP.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: NoD.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: NoD.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

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File list: NoD.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

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Full Text Available NoD.CDV.10.AllAg.Atrioventicular_canals mm9 No description Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.CDV.10.AllAg.Atrioventicular_canals.bed ...
File list: NoD.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available NoD.CDV.05.AllAg.Atrioventicular_canals mm9 No description Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.CDV.05.AllAg.Atrioventicular_canals.bed ...
File list: InP.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.CDV.50.AllAg.Atrioventicular_canals mm9 Input control Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.CDV.50.AllAg.Atrioventicular_canals.bed ...
File list: InP.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available InP.CDV.10.AllAg.Atrioventicular_canals mm9 Input control Cardiovascular Atrioventicular canals... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.CDV.10.AllAg.Atrioventicular_canals.bed ...
Estado actual de las investigaciones tafonómicas naturalistas en Punta Entrada y Monte León (patagonia meridional)

OpenAIRE

Muñoz, Sebastián Ramón; Cruz, Isabel

2017-01-01

Se presentan los resultados de las investigaciones tafonómicas naturalistas realizadas desde 2005 en la desembocadura del río Santa Cruz y el parque Nacional Monte león (Patagonia Meridional) dirigidas a conocer los modos en que tiene lugar el reciclado de restos de vertebrados en un mismo contexto ambiental, la estepa costera patagónica. Se resume el conocimiento generado sobre: el tiempo involucrado en la desarticulación de carcasas de vertebrados; los procesos y actores intervinientes y ...
Evaluation of the anterior and posterior ethmoidal canal by computed tomography

International Nuclear Information System (INIS)

Cankal, F.; Apaydin, N.; Acar, H.I.; Elhan, A.; Tekdemir, I.; Yurdakul, M.; Kaya, M.; Esmer, A.F.

2004-01-01

AIM: To examine the anatomy, length and angulation of the anterior and posterior ethmoidal canals (AECs and PECs) using computed tomography (CT), and to determine the anatomical landmarks in which the canals are expected to be seen in transverse and coronal planes. MATERIALS AND METHODS: CT images of 150 patients were analysed. One, 2, and 3 mm thick sections were obtained separately in axial and coronal images. The frequency of visualization of the AECs and PECs, and if present, a third canal, was noted. The course and the angulation of the AEC and the PEC in transverse and coronal planes were recorded. On axial sections the distance between the AEC and PEC and the previously defined landmarks were measured. On coronal images, the distances were calculated from the thickness of the cross-section and the number of sections between the various structures. RESULTS: The AEC was identified as a separate canal in 84% of patients, and was embedded in the ethmoid roof in 16%. The PEC was seen as a separate canal in 8% and was present in the ethmoid roof in 92%. On the 1 mm thick coronal and transverse sections, a third canal was identified at the junction of the middle and posterior third of the AEC-PEC distance in both of the images. The average lengths of these canals were 4-12 mm (mean 8.2 mm) for the AEC, and 2-13 mm (mean 7.6 mm) for the PEC. CONCLUSIONS: To avoid the complications that can develop during endoscopic sinus surgery; the course, length and the angulations of the anterior and posterior ethmoidal arteries and their canals can be identified by CT in standard positions if a sufficiently thin section thickness is used. The present study has shown the exact CT localization of the AECs and PECS, which are frequently overlooked when evaluating para-nasal sinuses
Effectiveness of EDTA as the irrigation solution to remove smear layer in root canal

OpenAIRE

Kurniasri Amas Achiar; Endang Sukartini

2009-01-01

One of the objectives of successful endodontic treatment is the hermetic obturation of the root canal system. To achieve this, the root canal filling must seal the canal space both apically and coronally to prevent the ingress of microorganisms or tissue fluids into the canal space. Apical leakage is reported a common reason for the clinical failure of endodontic therapy. Leakage through an obturated root canal is expected to take place at interfaces between sealer and dentin or sealer and gu...
Magnetic Resonance Imaging Quantification of Lumbar Spinal Canal Stenosis in Symptomatic Subjects

Directory of Open Access Journals (Sweden)

Siddarth Ragupathi

2017-10-01

Full Text Available Introduction: Low backache is a common condition to occur in the middle age. It is mainly caused by the degeneration of the intervertebral disc which forms the main support to the vertebral column. Lumbar spinal canal stenosis results in the compression of spinal cord and nerves at the level of lumbar vertebra. Aim: The purpose of this study is to measure the spinal canal dimensions and correlate with the clinical symptoms to establish a radiological criterion based on MRI for diagnosis of lumbar canal stenosis. This study is done to improve the diagnostic accuracy of lumbar spinal canal stenosis. Materials and Methods: Two hundred subjects with complaints of low backache without a traumatic history underwent Magnetic Resonance Imaging (MRI after assessment of pain by two methods: 1. Oswestry Disability Index (ODI scoring and 2. Wong Baker Facial Expression scale. All the images were qualitatively analyzed to obtain the MRI grading for central canal at various levels from L1 to S1 vertebra after making sure that the neural foramina is not involved. Anteroposterior (AP and transverse diameter of spinal canal at intervertebral disc and upper part of vertebral body levels and spinal canal area are measurements that are taken. Descriptive and inferential statistical analysis has been carried out in the present study. Results on continuous measurements are presented on mean±SD (min-max and results on categorical measurements are presented in number (%. Significance is assessed at 5% level of significance. Results: The spinal canal diameter measured along its AP and transverse direction is found to be correlating with the severity of low backache complained by the patient. Comparing the two methods of clinical assessment, ODI scoring was found to be more significant. Conclusion: The spinal canal measurements can be used as a radiologic criterion for diagnosis of acquired lumbar spinal canal stenosis. This will improve the diagnostic accuracy. However
Is forage productivity of meadows influenced by the afforestation of upstream hillsides? A study in NW Patagonia

Energy Technology Data Exchange (ETDEWEB)

Weigandt, M.; Gyenge, J.; Fernandez, M. E.; Varela, S.; Schlichter, T.

2011-07-01

Meadows are important reserves of water, with a key role in the maintenance of the biodiversity and productivity of ecosystems. In Patagonia, Argentina, afforestation with fast-growing exotic conifers has slowly but continuously increased over recent decades; though unfortunately, knowledge of the effects of afforestation on water resources remains scarce, with no information at all related to its impact on water dynamics and productivity of meadows located down slope to it. The effects of Pinus ponderosa afforestation on water dynamics (soil moisture contents and groundwater level) and productivity (aboveground forage productivity) of Northwest Patagonia meadows under xeric and humid conditions were analyzed. In the humid meadow, gravimetric soil water content, groundwater level and forage productivity were similar down slope of forested and non-forested slopes, with a trend towards higher forage productivity on the forested slope. In the xeric meadow, gravimetric soil water content was always higher down slope of the non-forested slope, with no difference in groundwater level between treatments. Forage productivity was statistically similar between situations (down slope of forested and non-forested slopes), with a trend towards higher productivity in the zone with higher soil water content. The main difference in the latter was related to differences in soil texture between zones. These results suggest that coniferous plantations located upstream of this type of meadow do not produce a direct effect on its aboveground forage productivity. These systems have high complexity linked to precipitation, geomorphology and previous history of land use, which determine primarily soil water dynamics and consequently, forage productivity. (Author) 42 refs.
Cervical Cord-Canal Mismatch: A New Method for Identifying Predisposition to Spinal Cord Injury.

Science.gov (United States)

Nouri, Aria; Montejo, Julio; Sun, Xin; Virojanapa, Justin; Kolb, Luis E; Abbed, Khalid M; Cheng, Joseph S

2017-12-01

The risk for spinal cord injuries (SCIs) ranging from devastating traumatic injuries, compression because of degenerative pathology, and neurapraxia is increased in patients with congenital spinal stenosis. Classical diagnostic criteria include an absolute anteroposterior diameter of spinal cord, which varies across patients, independent of canal size. Recent large magnetic resonance imaging studies of population cohorts have allowed newer methods to emerge that account for both cord and canal size by measuring a spinal cord occupation ratio (SCOR). A SCOR defined as ≥70% on midsagittal imaging or ≥80% on axial imaging appears to be an effective method of identifying cord-canal mismatch, but requires further validation. Cord-canal size mismatch predisposes patients to SCI because of 1) less space within the canal lowering the amount of degenerative changes needed for cord compression, and 2) less cerebrospinal fluid surrounding the spinal cord decreasing the ability to absorb kinetic forces directed at the spine. Patients with cord-canal mismatch have been reported to be at a substantially higher risk of traumatic SCI, and present with degenerative cervical myelopathy at a younger age than patients without cord-canal mismatch. However, neurologic outcome after SCI has occurred does not appear to be different in patients with or without a cord-canal mismatch. Recognition that canal and cord size are both factors which predispose to SCI supports that cord-canal size mismatch rather than a narrow cervical canal in isolation should be viewed as the underlying mechanism predisposing to SCI. Copyright © 2017. Published by Elsevier Inc.
Evaluation of the root canal shaping ability of two rotary nickel-titanium systems.

Science.gov (United States)

Al-Manei, K K; Al-Hadlaq, S M S

2014-10-01

The aim was to investigate the canal shaping abilities of the twisted file (TF) and GT series X file (GTX) systems. Sixty mesial root canals of mandibular molars with curvatures of 15-50° were divided randomly into two groups of 30 canals each. The teeth were sectioned horizontally at 3, 6 and 9 mm from the apex. Root canals were prepared with TF and GTX files, respectively, and the shaping abilities of the systems were evaluated at three levels (coronal, middle and apical) based on the comparison of pre- and post-instrumentation photographs using AutoCAD software. Preparation time was also assessed. Data from the two groups were compared statistically using the Student's t-test. There was no significant difference between the rotary systems in terms of change in root canal cross-sectional area, root canal transportation, centring ability or minimum dentine thickness. Remaining dentine thickness at the coronal and middle levels was similar in the TF and GTX groups, but GTX instruments left significantly less dentine than TF instruments on the mesial aspects of root canals at the apical level. Root canal preparation with TF instruments required significantly less time than with GTX instruments. The TF and GTX NiTi rotary instruments showed similar shaping abilities, but root canal preparation was more rapid with the TF than with the GTX system. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.
Design Of The Canal System Of KLA-60 Condensation Produce

International Nuclear Information System (INIS)

Sriawan; Wiranto, Slamet

2000-01-01

The RSG-GAS reactor pool ventilation system (KLA-60) which be used to avoid circulation of contamination air in the reactor hall, flow the 60% air from the pool surface to stack through the various filters. In case the isolation building the air from the pool surface is flooded back to the operation hall after exceed the heat exchanger, cooler and the various filters. One of the weakness of this system and must be solved by RSG is handing of the condensation water because in the canal system of the KLA-60 condensation produce is to be found some soiled like algae and to go the reactor pool. To solve this problem should be carried out research about the canal system of KLA-60 condensation produce and design the new canal system to find the good function. At the first design is carried out study about the function of the old of canal system of KLA-60 condensation produce. Base on this study have been carried out design of the canal system KLA-60 condensation produce, with can prevent the soiled to go to the reactor pool
Mandibular lingual vascular canals (MLVC): Evaluation on dental CTs of a case series

Energy Technology Data Exchange (ETDEWEB)

Scaravilli, Maria Serena; Mariniello, Mauro [Department of Oral and Maxillo-Facial Sciences, Section of Oral and Implant Surgery, University of Naples ' Federico II' , Naples (Italy); Sammartino, Gilberto, E-mail: serena.scaravilli@gmail.com [Department of Oral and Maxillo-Facial Sciences, Section of Oral and Implant Surgery, University of Naples ' Federico II' , Naples (Italy)

2010-11-15

Purpose: The aim of this study was to assess the anatomy of the mandibular lingual foramen (MLF) and its linked canals (mandibular lingual vascular canals - MLVC), describing their frequency, diameter, location, and course. Materials and methods: One hundred and fourteen computed tomography (CT) images of the mandible (57 male and 57 female; mean age 44.70 {+-} 12.53; age range 13-75 years, were evaluated. The CT sections were obtained on axial plane by using a bone reconstruction algorithm and then processed with dedicated software (Dentascan), with a standard protocol. Results: 103 patients (90.35%) had at least one lingual vascular canal and 52 (45.61%) had multiple (two or three) canals. The typical locations of MLVC were the midline of the mandible (median lingual canal [MLC]). The mean diameter of the lingual canals in the midline (MLC) was 0.8 mm {+-} 0. The direction of MLC progresses in an anterior and slightly caudal sense. Conclusions: Dental CT examination easily demonstrates the presence, position, direction and size of the lingual foramen and of the lingual vascular canals of the mandible. Radiologists and oral surgeons should be aware of these canals and their importance, in order to prevent bleeding complications during implants placement and other surgical procedures.
Leiomyoma of the anal canal: report of two cases.

Science.gov (United States)

Witz, M; Bernheim, J; Griffel, B; Dinbar, A

1986-10-01

Leiomyoma of the rectum and anal canal is an unusual clinical entity. Generally, it does not produce any clinical signs and in most cases it is discovered incidentally in the course of routine rectal examination. The clinical presentation, diagnosis, and surgical treatment are described in two presented cases of anal canal leiomyoma.
ProTaper rotary instrument fracture during root canal preparation: a comparison between rotary and hybrid techniques.

Science.gov (United States)

Farid, Huma; Khan, Farhan Raza; Rahman, Munawar

2013-03-01

This study aimed to compare the frequency of ProTaper rotary instrument fracture with rotary (conventional) and hybrid (rotary and hand files) canal preparation techniques. Secondary objectives were to determine whether there was an association of ProTaper file fracture with the canal curvature and to compare the mean time required for canal preparation in the two techniques. An in vitro experiment was conducted on 216 buccal canals of extracted maxillary and mandibular first molars. After creating an access cavity and a glide path for each canal, a periapical radiograph was taken and the canal curvature was measured with Schneider's technique. The canals were then randomly divided into Group A (rotary technique) and Group B (hybrid technique). The length of ProTaper files were measured before and after each canal preparation. Time taken for each canal preparation was recorded. A total of seven ProTaper files fractured in Group A (P=0.014) in canals with a curvature >25 degrees (PProTaper rotary files, although time consuming, was safer in canals having a curvature greater than 25 degrees.
Vestibulo-Ocular Reflex Abnormalities in Posterior Semicircular Canal Benign Paroxysmal Positional Vertigo: A Pilot Study

Directory of Open Access Journals (Sweden)

Tayyebe Fallahnezhad

2017-09-01

Full Text Available Introduction: Benign paroxysmal positional vertigo (BPPV, involving the semicircular canals, is one of the most common diseases of the inner ear. The video head impulse test (vHIT is a new test that examines the function of the canals. This study aimed to investigate the vestibulo-ocular reflex (VOR gain, gain asymmetry and saccades after stimulating all six canals in patients definitively diagnosed with posterior semicircular canal BPPV (PSC-BPPV. Materials and Methods: Twenty-nine unilateral PSC-BPPV patients with normal oculographic and caloric results were enrolled in this study. vHIT was performed on six canals, and VOR gain, gain asymmetry and saccades were measured. Results: Sixteen (55.17% patients had abnormal posterior canal VOR gains in the ipsilesional ear. VOR gains in both horizontal canals were within normal limits. Superior canal VOR gains were mostly lower than normal and were not correlated to PSC abnormalities (P>0.05. No corrective saccades could be observed. Conclusion: VOR gain in the direction of the posterior semicircular canal may be reduced in PSC-BPPV patients. Evaluation of PSC-VOR parameters could be beneficial, although superior canal measurements should be interpreted with caution.
La evolución del espacio social y urbano en la capital de la Patagonia chilena. Punta Arenas

Directory of Open Access Journals (Sweden)

Luis Inostroza Pino

2008-05-01

Razones del contexto mundial apoyadas por adecuadas decisiones a nivel local, son las que permitieron el desarrollo de la Patagonia y de la ciudad de Punta Arenas fundamentalmente hasta fines del siglo XIX. La iniciación del tráfico regular entre Europa y el Pacífico, con recalada obligada en la colonia, y las medidas de Puerto libre y de incentivo a la inmigración de colonos nacionales y extranjeros, influirán decisivamente en ese desarrollo. El modesto pueblo se transforma en un importante centro urbano.

The circulation of the cerebrospinal fluid (CSF) in the spinal canal

Science.gov (United States)

Sanchez, Antonio L.; Martinez-Bazan, Carlos; Lasheras, Juan C.

2016-11-01

Cerebrospinal Fluid (CSF) is secreted in the choroid plexus in the lateral sinuses of the brain and fills the subarachnoid space bathing the external surfaces of the brain and the spinal canal. Absence of CSF circulation has been shown to impede its physiological function that includes, among others, supplying nutrients to neuronal and glial cells and removing the waste products of cellular metabolism. Radionuclide scanning images published by Di Chiro in 1964 showed upward migration of particle tracers from the lumbar region of the spinal canal, thereby suggesting the presence of an active bulk circulation responsible for bringing fresh CSF into the spinal canal and returning a portion of it to the cranial vault. However, the existence of this slow moving bulk circulation in the spinal canal has been a subject of dispute for the last 50 years. To date, there has been no physical explanation for the mechanism responsible for the establishment of such a bulk motion. We present a perturbation analysis of the flow in an idealized model of the spinal canal and show how steady streaming could be responsible for the establishment of such a circulation. The results of this analysis are compared to flow measurements conducted on in-vitro models of the spinal canal of adult humans.
APOROCOTYLE MARIACHRISTINAE N. SP., AND A. YMAKARA VILLALBA & FERNANDEZ, 1986 (DIGENEA: APOROCOTYLIDAE) OF THE PINK CUSK-EEL, GENYPTERUS BLACODES (OPHIDIIFORMES: OPHIDIIDAE) FROM PATAGONIA, ARGENTINA

Czech Academy of Sciences Publication Activity Database

Hernandez-Orts, J.S.; Alama-Bermejo, Gema; Carillo, J.M.; García, N.A.; Crespo, E.A.; Raga, J. A.; Montero, E. E.

2012-01-01

Roč. 19, č. 4 (2012), s. 319-330 ISSN 1252-607X R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Aporocotylidae * Aporocotyle * A. mariachristinae n. sp. * A. ymakara * Genypterus blacodes * Ophidiidae * Patagonia * Argentina * rDNA sequences Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.116, year: 2012
[Evaluation of preparation of curved root canals using hand-used ProTaper].

Science.gov (United States)

Nie, Min; Zhao, Xin-Chen; Peng, Bin; Fan, Ming-Wen; Bian, Zhuan

2009-05-01

To evaluate the shaping ability of hand-used ProTaper on curved canals using Endodontic Cube. Fifty-four curved root canals in vitro were selected and divided into three groups according to the curved degree (alpha), group A: 0 degrees hand-used ProTaper. Before and after shaping, photograph of all the sections were taken under a stereomicroscope. Statistical analyses were performed. The dentin cutting quantity of the whole canal prepared with ProTaper in group B and C was larger than that of group A. The deviation distance of the whole canal prepared by ProTaper in group C was significantly larger than that in group A, and the deviation distance in middle portion larger than that in group B. The maintaining ability in the middle portion of group C by ProTaper was worse than that of group A and B. The curvature of root canal may increase the cutting quantity of the -dentin and reduce the ability of remaining original canal shape prepared by ProTaper.
NMR imaging of the vertebral column and the spinal canal. 2. rev. and enl. ed.

International Nuclear Information System (INIS)

Forsting, Michael; Uhlenbrock, Detlev; Wanke, Isabel; Universitaetsklinikum Essen

2009-01-01

The book on the MRT (magnetic resonance tomography) of the vertebral cord and spinal canal covers the following topics: physics fundamentals and application; malformation of the spinal canal; degenerative vertebral column diseases; vertebral column and spinal canal carcinomas; inflammatory diseases of the vertebral column and the spinal canal; applicability of MRT in case of acute spinal cord traumata; vascular diseases of the spinal canal
The effect of four different irrigation systems in the removal of a root canal sealer.

Science.gov (United States)

Grischke, J; Müller-Heine, A; Hülsmann, M

2014-09-01

The aim of this study was to compare the efficiency of sonic, ultrasonic, and hydrodynamic devices in the removal of a root canal sealer from the surface and from simulated irregularities of root canals. Fifty-three root canals with two standardized grooves in the apical and coronal parts of longitudinally split roots were covered with AH Plus root canal sealer. Compared were the effects of (control) syringe irrigation, (1) CanalBrush, (2) passive ultrasonic irrigation, (3) EndoActivator, and (4) RinsEndo on the removal of the sealer. The specimens were divided into four groups (N = 12) and one control group (N = 5) via randomization. The amount of remaining sealer in the root canal irregularities was evaluated under a microscope using a 4-grade scoring system, whereas the remaining sealer on the root canal surface was evaluated with a 7-grade scoring system. Passive ultrasonic irrigation is more effective than the other tested irrigation systems or syringe irrigation in removing sealer from root canal walls (p irrigation shows a superior effect on sealer removal from the root canal surface during endodontic retreatment. Cleaning of lateral grooves seems not to be possible with one of the techniques investigated. Incomplete removal of root canal sealer during re-treatment may cause treatment failure. Passive Ultrasonic irrigation seems to be the most effective system to remove sealer from a root canal.
Bank erosion of navigation canals in the western and central Gulf of Mexico

Science.gov (United States)

Thatcher, Cindy A.; Hartley, Stephen B.; Wilson, Scott A.

2011-01-01

Erosion of navigation canal banks is a direct cause of land loss, but there has been little quantitative analysis to determine why certain major canals exhibit faster widening rates (indicative of erosion) than others in the coastal zones of Texas, Louisiana, Mississippi, and Alabama. We hypothesize that navigation canals exhibit varying rates of erosion based on soil properties of the embankment substrate, vegetation type, geologic region (derived from digital versions of state geologic maps), and the presence or absence of canal bank armaments (that is, rock rip-rap, concrete bulkheads, or other shoreline protection structures). The first objective of this project was to map the shoreline position and substrate along both banks of the navigation canals, which were digitized from 3 different time periods of aerial photography spanning the years of 1978/79 to 2005/06. The second objective was to quantify the erosion rates of the navigation canals in the study area and to determine whether differences in erosion rates are related to embankment substrate, vegetation type, geologic region, or soil type. To measure changes in shoreline position over time, transects spaced at 50-m (164-ft) intervals were intersected with shorelines from all three time periods, and an annual rate of change was calculated for each transect. Mean annual rates of shoreline change ranged from 1.75 m/year (5.74 ft/year) on the west side of the Atchafalaya River, La., where there was shoreline advancement or canal narrowing, to -3.29 m/year (-10.79 ft/year) on the south side of the Theodore Ship Channel, Ala., where there was shoreline retreat or erosion. Statistical analysis indicated that there were significant differences in shoreline retreat rates according to geologic region and marsh vegetation type, and a weak relationship with soil organic content. This information can be used to better estimate future land loss rates associated with navigation canals and to prioritize the location of
MRI diagnosis of embryonal tumors in the spinal canal

International Nuclear Information System (INIS)

Sun Jilin; Zhang Xinchuan; Zhang Huaning; Liu Lianxiang; Wu Yujin

1997-01-01

To evaluate MRI diagnostic value of the embryonal tumors in the spinal canal. Materials and methods: The MRI appearances of 15 cases of histologically confirmed embryonal tumors in the spinal canal were analyzed. (1) Lipoma (3 cases) had characteristic MRI appearance, demonstrating high signal intensity on T 1 WI, and moderately high signal on T 2 WI. High signal intensity of the lipoma was turned into low signal intensity by fat suppression technique. (2) Dermoids (2 cases) and epidermoid (7 cases) exhibiting low or iso-low signal on T 1 WI and high or iso-high signal on T 2 WI. All had an iso-intense capsule on T 1 WI. However, the two tumors could not be distinguished from each other. (3) Teratoma (3 cases) appeared as a mass of inhomo-generous signals in the spinal canal including soft tissue, fatty tissue and calcification within the same tumor. The diagnosis of embryonal tumors in the spinal canal mainly depend on their MRI appearances, specific tumor location and patient's age
Nutrient canals on mandibular anterior region in cone beam computed tomography

International Nuclear Information System (INIS)

Kang, Jung Ho; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2006-01-01

To evaluate location, distribution, diameter, and length of the nutrient canals on mandibular anterior region using a cone beam computed tomography (CBCT). Mandibular CBCT was performed on 33 adults (18 males and 15 female) with no history of systemic disease, and any other dental surgery history. Location, distribution, diameter, and length of the nutrient canals on mandibular anterior region were radiographically evaluated. A statistical comparison was done by SPSS. In the location and distribution of nutrient canals, they were found in 6.8% at labial portion above root apex, in 93.28% at lingual portion above root apex in 46.2% at labial portion below root apex, and in 53.6% at lingual portion below root apex. Nutrient canals at lingual portion above root apex were most frequently observed between central and lateral incisors, and those at labial and lingual portion below root apex were most frequently observed between central incisors. The mean diameters of nutrient canals were 0.54 mm at labial portion above root apex, 0.61 mm at lingual portion above root apex, 0.66 mm at labial portion below root apex, and 0.76 mm at lingual portion below root apex. The mean lengths of nutrient canals were 2.63 mm at labial portion above root apex, 3.74 mm at lingual portion above root apex, 4.51 mm at labial portion below root apex, and 6.77 mm at lingual portion below root apex. CBCT is useful device to evaluate the anatomical structure of nutrient canals on mandibular anterior region
Nutrient canals on mandibular anterior region in cone beam computed tomography

Energy Technology Data Exchange (ETDEWEB)

Kang, Jung Ho; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan [Kyung Hee Univ. College of Dentistry, Seoul (Korea, Republic of)

2006-09-15

To evaluate location, distribution, diameter, and length of the nutrient canals on mandibular anterior region using a cone beam computed tomography (CBCT). Mandibular CBCT was performed on 33 adults (18 males and 15 female) with no history of systemic disease, and any other dental surgery history. Location, distribution, diameter, and length of the nutrient canals on mandibular anterior region were radiographically evaluated. A statistical comparison was done by SPSS. In the location and distribution of nutrient canals, they were found in 6.8% at labial portion above root apex, in 93.28% at lingual portion above root apex in 46.2% at labial portion below root apex, and in 53.6% at lingual portion below root apex. Nutrient canals at lingual portion above root apex were most frequently observed between central and lateral incisors, and those at labial and lingual portion below root apex were most frequently observed between central incisors. The mean diameters of nutrient canals were 0.54 mm at labial portion above root apex, 0.61 mm at lingual portion above root apex, 0.66 mm at labial portion below root apex, and 0.76 mm at lingual portion below root apex. The mean lengths of nutrient canals were 2.63 mm at labial portion above root apex, 3.74 mm at lingual portion above root apex, 4.51 mm at labial portion below root apex, and 6.77 mm at lingual portion below root apex. CBCT is useful device to evaluate the anatomical structure of nutrient canals on mandibular anterior region.
Canal rays

International Nuclear Information System (INIS)

Goldstein, Eugen

2010-01-01

For more than fifty years the German physicist Eugen Goldstein was engaged in an obscure fringe field of physics, on which he has impressed like no other: Electrical gas discharges. Goldstein describes in this book his discovery of canal rays, which has given important impulses for modern atomic physics. For his research Goldstein received the Prix Hebert of the Parisienne Academie des sciences, the Hughes medal, and was repeatedly proposed for the Nobel prize. In Germany for the Jewish scientist the acknowledgement remained far-reachingly refused until after the war.
Geometric analysis of root canals prepared by four rotary NiTi shaping systems.

Science.gov (United States)

Hashem, Ahmed Abdel Rahman; Ghoneim, Angie Galal; Lutfy, Reem Ahmed; Foda, Manar Yehia; Omar, Gihan Abdel Fatah

2012-07-01

A great number of nickel-titanium (NiTi) rotary systems with noncutting tips, different cross-sections, superior resistance to torsional fracture, varying tapers, and manufacturing method have been introduced to the market. The purpose of this study was to evaluate and compare the effect of 4 rotary NiTi preparation systems, Revo-S (RS; Micro-Mega, Besancon Cedex, France), Twisted file (TF; SybronEndo, Amersfoort, The Netherlands), ProFile GT Series X (GTX; Dentsply, Tulsa Dental Specialties, Tulsa, OK), and ProTaper (PT; Dentsply Maillefer, Ballaigues, Switzerland), on volumetric changes and transportation of curved root canals. Forty mesiobuccal canals of mandibular molars with an angle of curvature ranging from 25° to 40° were divided according to the instrument used in canal preparation into 4 groups of 10 samples each: group RS, group TF, group GTX, and group PT. Canals were scanned using an i-CAT CBCT scanner (Imaging Science International, Hatfield, PA) before and after preparation to evaluate the volumetric changes. Root canal transportation and centering ratio were evaluated at 1.3, 2.6, 5.2, and 7.8 mm from the apex. The significance level was set at P ≤ .05. The PT system removed a significantly higher amount of dentin than the other systems (P = .025). At the 1.3-mm level, there was no significant difference in canal transportation and centering ratio among the groups. However, at the other levels, TF maintained the original canal curvature recording significantly the least degree of canal transportation as well as the highest mean centering ratio. The TF system showed superior shaping ability in curved canals. Revo-S and GTX were better than ProTaper regarding both canal transportation and centering ability. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Retreatment of a mandibular second premolar with two canals in two roots

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Chiara Fossati

2018-06-01

Full Text Available Aim: To present a case of retreatment in mandibular second premolar with two canals in two roots. Summary: Locating, cleaning and shaping the entire root canal system may represent a difficult challenge particularly in mandibular premolars, because of their complex canal systems.For this reason mandibular premolars are often considered the most difficult of all teeth on which to perform successful endodontic treatment. Vertucci stated that the second premolar has one root canal at the apex in 97.5% of the teeth studied and two canals in only 2.5%.1 The following case report describes the diagnosis and retreatment of a second premolar with two canal in two roots.Key learning points: (1 The major cause of failure in root canal therapy is the inability to localize and treat all of the canals of the root canal system. (2 Mandibular premolars have complex canal systems. (3 Mandibular premolars have a high risk of missed anatomy. (4 Preoperative radiograph interpretation is essential to evaluate and detect uncommon anatomies. (5 The operating microscope and CBCT interpretation are fundamental in confirming and preventing mistakes about the configuration of mandibular premolars. Riassunto: Obiettivi: Presentare un caso clinico di ritrattamento canalare di un secondo premolare mandibolare con due canali e due radici. Riassunto: Individuare, sagomare, detergere l’intero sistema radicolare presenta una sfida difficile in ambito endodontico e in particolar modo nei premolari mandibolari per il loro complesso sistema canalare. I premolari mandibolari sono spesso considerati i denti più difficili in cui effettuare una terapia endodontica.Vertucci riscontrò che i secondi premolari mandibolari hanno una radice e un canale nel 97.5% e due canali in solo il 2.5%.1Il case report seguente descrive la diagnosi e il ritrattamento di un secondo premolare con due canali in due radici.Punti chiave di apprendimento: 1. La maggior causa di fallimento endodontico �
Cone beam CT findings of retromolar canals: Report of cases and literature review

Energy Technology Data Exchange (ETDEWEB)

Han, Sang Sun [Dept. of Dental Hygiene, Eulji University, Seongnam (Korea, Republic of); Park, Chang Seo [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Yonsei University, Seoul (Korea, Republic of)

2013-12-15

A retromolar canal is an anatomical variation in the mandible. As it includes the neurovascular bundle, local anesthetic insufficiency can occur, and an injury of the retromolar canal during dental surgery in the mandible may result in excessive bleeding, paresthesia, and traumatic neuroma. Using imaging analysis software, we evaluated the cone-beam computed tomography (CT) images of two Korean patients who presented with retromolar canals. Retromolar canals were detectable on the sagittal and cross-sectional images of cone-beam CT, but not on the panoramic radiographs of the patients. Therefore, the clinician should pay particular attention to the identification of retromolar canals by preoperative radiographic examination, and additional cone beam CT scanning would be recommended.
Cone beam CT findings of retromolar canals: Report of cases and literature review

International Nuclear Information System (INIS)

Han, Sang Sun; Park, Chang Seo

2013-01-01

A retromolar canal is an anatomical variation in the mandible. As it includes the neurovascular bundle, local anesthetic insufficiency can occur, and an injury of the retromolar canal during dental surgery in the mandible may result in excessive bleeding, paresthesia, and traumatic neuroma. Using imaging analysis software, we evaluated the cone-beam computed tomography (CT) images of two Korean patients who presented with retromolar canals. Retromolar canals were detectable on the sagittal and cross-sectional images of cone-beam CT, but not on the panoramic radiographs of the patients. Therefore, the clinician should pay particular attention to the identification of retromolar canals by preoperative radiographic examination, and additional cone beam CT scanning would be recommended.
Endodontic management of permanent mandibular molars with 6 root canals: report of 3 cases.

Science.gov (United States)

Malhotra, Amit; Ahlawat, Jyoti; Bansal, Chirag; Tahiliani, Divya

2016-01-01

Aberrations in the internal dental anatomy present challenges for clinicians performing endodontic therapy. These challenges have been partly resolved in recent years by a more comprehensive knowledge of root canal anatomy as well as advancements in the endodontic armamentarium. The aim of this case series is to describe successful root canal treatment, under magnification, in 3 cases of mandibular first molars with 6 root canals. Two of these teeth had 2 roots (mesial and distal) with 3 canals in each root; the third tooth had 3 root canals located mesially and 3 present distally as well as a radix entomolaris. A distal root with 3 canals is rare; however, it is important to look for such anatomical variations to ensure successful endodontic therapy.
Effect of Canal Bank Filtration on Quality of Water Long Hyderabad City

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IMDAD ALI KANDHAR

2016-07-01

Full Text Available The focus of the present study was to examine the effect of canal bank filtration on the quality of water and the geological settings along the banks of canals at the shallow depth aquifers. The four Model wells were drilled at different locations of the Line channel, Pinyari and phulali canals in the study area. The samples of soil were collected throughout drilling of the model wells for the analysis of grain size distribution .In addition to this, canal water and model well water samples were collected and analyzed for the water quality characteristics during winter and summer seasons. The analysis of soil and water samples reveals that the ground water is influenced by the grain size distribution, hydraulic conductivity and the location of the model Wells. The model well that has higher percentage of 0.075 mm of grain size distribution(hydraulic conductivity between 10-25 ft/day was more suitable for the filtration of the canal water through its banks, followed by 0.15 mm of grain size distribution (hydraulic conductivity > 25ft/ day. Moreover, the present study also shows that the canal water filtration is suitable in terms of total alkalinity, nitrate-nitrogen, total iron and pH to get the potable water at the location near upstream of the canal, especially in the summer season.
External auditory canal atresia of probable congenital origin in a dog.

Science.gov (United States)

Schmidt, K; Piaia, T; Bertolini, G; De Lorenzi, D

2007-04-01

A nine-month-old Labrador retriever was referred to the Clinica Veterinaria Privata San Marco because of frequent headshaking and downward turning of the right ear. Clinical examination revealed that there was no external acoustic meatus in the right ear. Computed tomography confirmed that the vertical part of the right auditory canal ended blindly, providing a diagnosis of external auditory canal atresia. Cytological examination and culture of fluid from the canal and the bulla revealed only aseptic cerumen; for this reason, it was assumed that the dog was probably affected by a congenital developmental deformity of the external auditory canal. Reconstructive surgery was performed using a "pull-through" technique. Four months after surgery the cosmetic and functional results were satisfactory.
Paleomagnetism of Jurassic and Cretaceous rocks in central Patagonia: a key to constrain the timing of rotations during the breakup of southwestern Gondwana?

Science.gov (United States)

Geuna, Silvana E.; Somoza, Rubén; Vizán, Haroldo; Figari, Eduardo G.; Rinaldi, Carlos A.

2000-08-01

A paleomagnetic study in Jurassic and Cretaceous rocks from the Cañadón Asfalto basin, central Patagonia, indicates the occurrence of about 25-30° clockwise rotation in Upper Jurassic-lowermost Cretaceous rocks, whereas the overlying mid-Cretaceous rocks do not show evidence of rotation. This constrains the tectonic rotation to be related to a major regional unconformity in Patagonia, which in turn seems to be close in time with the early opening of the South Atlantic Ocean. The sense and probably the timing of this rotation are similar to those of other paleomagnetically detected rotations in different areas of southwestern Gondwana, suggesting a possible relationship between these and major tectonic processes related with fragmentation of the supercontinent. On the other hand, the mid-Cretaceous rocks in the region yield a paleopole located at Lat. 87° South, Long. 159° East, A95=3.8°. This pole position is consistent with coeval high-quality paleopoles of other plates when transferred to South American coordinates, implying it is an accurate determination of the Aptian (circa 116 Ma) geomagnetic field in South America.
Instrument separation analysis of multi-used ProTaper Universal rotary system during root canal therapy.

Science.gov (United States)

Wu, Jintao; Lei, Gang; Yan, Ming; Yu, Yan; Yu, Jinhua; Zhang, Guangdong

2011-06-01

The purpose of this study was to identify the influential factors responsible for clinical instrument separation of reused ProTaper Universal rotary instruments (Dentsply Maillefer, Ballaigues, Switzerland). Six thousand one hundred fifty-four root canals in 2,654 teeth were prepared using ProTaper Universal files in endodontic clinics. Separation incidence was determined based on the number of treated teeth or canals. Data were collected including the size of fractured instrument, the length and location of a broken segment within the root canal, and the curvature of canal. The chi-square test and independent samples t test were used to determine the statistical significance. The overall instrument separation incidences were 2.6% according to the number of teeth and 1.1% according to the canal number, respectively. Separation incidences according to the number of teeth or canals were significantly higher (P molars than those in premolars or anterior teeth. Because of its largest diameter, F3 file presented the highest separation incidence according to the number of teeth (1.0%) or canals (0.4%); 47.5% instrument separation of mandibular molars and 61.5% instrument separation of maxillary molars happened in the mesiobuccal canals. Moreover, 91.4% fragments were located in the apical third of root canals, and 54.2% instrument separation occurred in severely curved canals. There was a significant difference (P < .05) in the mean fracture length between shaping (2.42 ± 0.73 mm) and finishing files (3.32 ± 0.73 mm). Separation incidence according to the canal number is more reliable than that according to the number of teeth because of the variable canal number in different teeth. The tooth type, rotary file size, canal location, and anatomy were correlated with the instrument separation of reused ProTaper Universal files. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Early Squamous Cell Carcinoma of the Anal Canal Resected by Endoscopic Submucosal Dissection

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Yuzuru Tamaru

2015-04-01

Full Text Available The standard treatment approach for squamous cell carcinoma (SCC of the anal canal includes abdominoperineal resection and chemoradiotherapy. However, there are currently very few reports of early SCC of the anal canal resected by endoscopic submucosal dissection (ESD. We report 2 rare cases of SCC of the anal canal resected by ESD. In case 1, a 66-year-old woman underwent a colonoscopy due to blood in her stool, and an elevated lesion, 15 mm in size, was identified from the rectum to the dentate line of the anal canal on internal hemorrhoids. The lesion was diagnosed as an early SCC of the anal canal, and ESD was successfully performed. The histopathological diagnosis was SCC in situ. In case 2, a 71-year-old woman underwent a colonoscopy due to constipation, and an elevated lesion, 25 mm in size, was identified from the dentate line to the anal canal. The lesion was diagnosed as early-stage SCC of the anal canal, and ESD was successfully performed. The histopathological diagnosis was SCC in situ. No complications or recurrence after ESD occurred in either case.

The Use of Lasers in Disinfection and Cleaning of Root Canals: a Review

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Ivica Anić

2014-01-01

Full Text Available The outcome of root canal treatment is based on efficient disinfection of the root canal system and prevention of reinfection. Current chemomechanical cleaning methods do not always achieve these goals, and insufficient root canal disinfection is the main reason for endodontic failure. Due to high energy content and specific characteristics of laser light, laser treatment has been proposed for cleaning and disinfecting the root canal system. This paper reviews the literature covering the effect of Er:YAG, Er,Cr:YSGG, Nd:YAG and diode laser on the root canal wall in the removal of smear layer and against intracanal bacteria. Recently, the use of laser energy to induce cavitation and acoustic streaming of intracanal irrigants has been investigated. Based on recent literature, it can be concluded that lasers have bactericidal effects. However, they still cannot replace sodium hypochlorite and should be considered as an adjunct to the current chemical root canal disinfection protocols. Certain lasers can help in removing the smear layer and debris and can modify the morphology of the root canal wall. Unfortunately, there have not been enough randomized clinical studies evaluating endodontic treatment outcome following the use of laser.
Retention of Root Canal Posts

DEFF Research Database (Denmark)

Sahafi, A; Benetti, Ana Raquel; Flury, S

2015-01-01

The aim of this study was to investigate the effect of the cement film thickness of a zinc phosphate or a resin cement on retention of untreated and pretreated root canal posts. Prefabricated zirconia posts (CosmoPost: 1.4 mm) and two types of luting cements (a zinc phosphate cement [DeTrey Zinc...... received tribochemical silicate coating according to the manufacturer's instructions. Posts were then luted in the prepared root canals (n=30 per group). Following water storage at 37°C for seven days, retention of the posts was determined by the pull-out method. Irrespective of the luting cement......, pretreatment with tribochemical silicate coating significantly increased retention of the posts. Increased cement film thickness resulted in decreased retention of untreated posts and of pretreated posts luted with zinc phosphate cement. Increased cement film thickness had no influence on retention...
78 FR 18479 - Drawbridge Operation Regulations; Inner Harbor Navigation Canal, New Orleans, LA

Science.gov (United States)

2013-03-27

... Operation Regulations; Inner Harbor Navigation Canal, New Orleans, LA AGENCY: Coast Guard, DHS. ACTION... across the Inner Harbor Navigation Canal, mile 4.6, at New Orleans, Louisiana. This deviation is... Seabrook Highway crossing the Inner Harbor Navigation Canal, mile 4.6, in New Orleans, Louisiana. The...
The hypoglossal canal and the origin of human vocal behavior

Science.gov (United States)

Kay, Richard F.; Cartmill, Matt; Balow, Michelle

1998-01-01

The mammalian hypoglossal canal transmits the nerve that supplies the muscles of the tongue. This canal is absolutely and relatively larger in modern humans than it is in the African apes (Pan and Gorilla). We hypothesize that the human tongue is supplied more richly with motor nerves than are those of living apes and propose that canal size in fossil hominids may provide an indication about the motor coordination of the tongue and reflect the evolution of speech and language. Canals of gracile Australopithecus, and possibly Homo habilis, fall within the range of extant Pan and are significantly smaller than those of modern Homo. The canals of Neanderthals and an early “modern” Homo sapiens (Skhul 5), as well as of African and European middle Pleistocene Homo (Kabwe and Swanscombe), fall within the range of extant Homo and are significantly larger than those of Pan troglodytes. These anatomical findings suggest that the vocal capabilities of Neanderthals were the same as those of humans today. Furthermore, the vocal abilities of Australopithecus were not advanced significantly over those of chimpanzees whereas those of Homo may have been essentially modern by at least 400,000 years ago. Thus, human vocal abilities may have appeared much earlier in time than the first archaeological evidence for symbolic behavior. PMID:9560291
Dislocation of the incus into the external auditory canal after mountain-biking accident.

Science.gov (United States)

Saito, T; Kono, Y; Fukuoka, Y; Yamamoto, H; Saito, H

2001-01-01

We report a rare case of incus dislocation to the external auditory canal after a mountain-biking accident. Otoscopy showed ossicular protrusion in the upper part of the left external auditory canal. CT indicated the disappearance of the incus, and an incus-like bone was found in the left external auditory canal. There was another bony and board-like structure in the attic. During the surgery, a square-shaped bony plate (1 x 1 cm) was found in the attic. It was determined that the bony plate had fallen from the tegmen of the attic. The fracture line in the posterosuperior auditory canal extending to the fossa incudis was identified. According to these findings, it was considered that the incus was pushed into the external auditory canal by the impact of skull injury through the fractured posterosuperior auditory canal, which opened widely enough for incus dislocation. Copyright 2001 S. Karger AG, Basel
Maxillary first molar with 7 root canals diagnosed using cone-beam computed tomography

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Evaldo Rodrigues

2017-02-01

Full Text Available Root canal anatomy is complex, and the recognition of anatomic variations could be a challenge for clinicians. This case report describes the importance of cone beam computed tomographyic (CBCT imaging during endodontic treatment. A 23 year old woman was referred by her general dental practitioner with the chief complaint of spontaneous pain in her right posterior maxilla. From the clinical and radiographic findings, a diagnosis of symptomatic irreversible pulpitis was made and endodontic treatment was suggested to the patient. The patient underwent CBCT examination, and CBCT scan slices revealed seven canals: three mesiobuccal (MB1, MB2, and MB3, two distobuccal (DB1 and DB2, and two palatal (P1 and P2. Canals were successfully treated with reciprocating files and filled using single-cone filling technique. Precise knowledge of root canal morphology and its variation is important during root canal treatment. CBCT examination is an excellent tool for identifying and managing these complex root canal systems.
Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

Energy Technology Data Exchange (ETDEWEB)

Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de, E-mail: sousanet@forp.usp.br [Universidade de São Paulo (USP), Ribeirao Preto, SP (Brazil). Departamento de Odontologia Restauradora; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi [Universidade de Ribeirão Preto (UNAERP), Ribeirão Preto, SP (Brazil). Departmento de Endodontia

2017-09-15

The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm{sup 3}, 58.51 mm{sup 2}, and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)
Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

International Nuclear Information System (INIS)

Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi

2017-01-01

The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm 3 , 58.51 mm 2 , and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)
The Inauguration of Suez Canal and Its Impacts on Navigation in seas

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maryam sheypari

2016-03-01

Full Text Available The inauguration of Suez Canal, which connects the Mediterranean Sea to Red Sea, had a great impact on marine communications. In other words, this canal not only offered the easier access of European countries to their colonies in Asia because of the new marine route between Asia and Europe but also developed the use of steamboats instead of sailboats due to its specific geographical position. In fact, the trade between Asia and Europe spanned via the seas located between Asia and Europe after four centuries as the result of inauguration of Suez Canal in 1869A.D. Furthermore, the importance of Seas i.e. Mediterranean Sea, Red Sea and black Sea had the great economic _ political role in the world and the expansion of rivalry between countries in Persian Gulf due to this canal. This study investigates to the process of diving Suez and the influence of Suez Canal on marine changes among the countries, especially in Persian Gulf by the beginning of the First World War. The outcome of this study demonstrates that the inauguration of Suez Canal led to the rivalry situation for England in the period of its supremacy.
Radiation-induced polymerization of 1, 3-butadiene in urea canal complex as studied by broad line NMR

International Nuclear Information System (INIS)

Yoshii, Fumio; Hayakawa, Naohiro; Abe, Toshihiko

1975-01-01

Dependence of the NMR spectrum on the molar ratio of 1,3-butadiene to urea, temperature dependence of the spectrum and changes of the spectrum during polymerization were observed. The results were discussed in comparison with previously reported results for the canal polymerization of acrylonitrile and vinyl chloride. 1,3-butadiene formes a canal complex with the molar ratio of 1 to 4 for 1,3-butadiene to urea. The urea canal complex is decomposed at -15 0 C. The spectrum of 1,3-butadiene in urea canal complex shows existence of a remarkably mobile component which was not observed on the spectra of acrylonitrile - urea of vinyl chloride - urea canal complex. The line width of 1,3-butadiene in the urea canal complex except the very narrow component was broader than that for vinyl chloride in the urea canal complex over an observed temperature range. The line width of urea formed the canal decreases at lower temperature than those of urea in vinyl chloride - urea canal complex. The post-polymerization of 1,3-butadiene in the urea canal complex started clearly from -78 0 C and completes when the temperature was raised to 20 0 C. The polymerization will be proceeded by the such way that monomer molecules move to the active center in the canal, as considered in the case of the polymerization of acrylonitrile and vinyl chloride in the canal complex. The crystal structure of the urea canal was maintained during polymerization and than the polybutadiene - urea canal complex was necessarily formed after the polymerization. The formation of the polymer - urea canal complex has distinct difference between 1,3-butadiene and acrylonitrile or vinyl chloride. For acrylonitrile and vinyl chloride the canals around the polymer formed are destroyed. The structure of polybutadiene - urea canal complex was hexagonal having a=8.21, c=10.50 A. (auth.)
Crecimiento anual de cuatro especies arbóreas con yemas desnudas nativas de los bosques templados húmedos de Patagonia

OpenAIRE

Sosa, Claudia M; Puntieri, Javier G

2016-01-01

Las especies vegetales que habitan en regiones con bajo nivel de estacionalidad en el clima suelen presentar rasgos morfo-arquitecturales que ocurren con menor frecuencia en especies de regiones con clima estacional. El objetivo de este estudio fue evaluar el crecimiento primario en vivero de cuatro especies leñosas típicas de los bosques templados húmedos de Patagonia, conocidos como selva valdiviana, donde el grado de estacionalidad es menos marcado que en otros bosques patagónicos. Las esp...
Bifid mandibular canal: a rare or underestimated entity?

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Ibrahim Nasseh

2016-10-01

Full Text Available One of the rare anatomical variations that can be of significant importance for the dentist is the bifid mandibular canal. Many complications can occur from this condition such as failure of anesthesia when performing inferior alveolar nerve block, difficulties during the surgical extraction of the third mandibular molar, and during implants placement. Therefore, good knowledge of this condition is essential. In this report, we describe the radiographic finding of a unilateral bifid mandibular canal.
Semicircular canals in Anolis lizards: ecomorphological convergence and ecomorph affinities of fossil species

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Dickson, Blake V.; Sherratt, Emma; Losos, Jonathan B.; Pierce, Stephanie E.

2017-10-01

Anolis lizards are a model system for the study of adaptive radiation and convergent evolution. Greater Antillean anoles have repeatedly evolved six similar forms or ecomorphs: crown-giant, grass-bush, twig, trunk, trunk-crown and trunk-ground. Members of each ecomorph category possess a specific set of morphological, ecological and behavioural characteristics which have been acquired convergently. Here we test whether the semicircular canal system-the organ of balance during movement-is also convergent among ecomorphs, reflecting the shared sensory requirements of their ecological niches. As semicircular canal shape has been shown to reflect different locomotor strategies, we hypothesized that each Anolis ecomorph would have a unique canal morphology. Using three-dimensional semilandmarks and geometric morphometrics, semicircular canal shape was characterized in 41 Anolis species from the Greater Antilles and the relationship between canal shape and ecomorph grouping, phylogenetic history, size, head dimensions, and perch characteristics was assessed. Further, canal morphology of modern species was used to predict the ecomorph affinity of five fossil anoles from the Miocene of the Dominican Republic. Of the covariates tested, our study recovered ecomorph as the single-most important covariate of canal morphology in modern taxa; although phylogenetic history, size, and head dimensions also showed a small, yet significant correlation with shape. Surprisingly, perch characteristics were not found to be significant covariates of canal shape, even though they are important habitat variables. Using posterior probabilities, we found that the fossil anoles have different semicircular canals shapes to modern ecomorph groupings implying extinct anoles may have been interacting with their Miocene environment in different ways to modern Anolis species.
Semicircular canals in Anolis lizards: ecomorphological convergence and ecomorph affinities of fossil species.

Science.gov (United States)

Dickson, Blake V; Sherratt, Emma; Losos, Jonathan B; Pierce, Stephanie E

2017-10-01

Anoli s lizards are a model system for the study of adaptive radiation and convergent evolution. Greater Antillean anoles have repeatedly evolved six similar forms or ecomorphs: crown-giant, grass-bush, twig, trunk, trunk-crown and trunk-ground. Members of each ecomorph category possess a specific set of morphological, ecological and behavioural characteristics which have been acquired convergently. Here we test whether the semicircular canal system-the organ of balance during movement-is also convergent among ecomorphs, reflecting the shared sensory requirements of their ecological niches. As semicircular canal shape has been shown to reflect different locomotor strategies, we hypothesized that each Anolis ecomorph would have a unique canal morphology. Using three-dimensional semilandmarks and geometric morphometrics, semicircular canal shape was characterized in 41 Anolis species from the Greater Antilles and the relationship between canal shape and ecomorph grouping, phylogenetic history, size, head dimensions, and perch characteristics was assessed. Further, canal morphology of modern species was used to predict the ecomorph affinity of five fossil anoles from the Miocene of the Dominican Republic. Of the covariates tested, our study recovered ecomorph as the single-most important covariate of canal morphology in modern taxa; although phylogenetic history, size, and head dimensions also showed a small, yet significant correlation with shape. Surprisingly, perch characteristics were not found to be significant covariates of canal shape, even though they are important habitat variables. Using posterior probabilities, we found that the fossil anoles have different semicircular canals shapes to modern ecomorph groupings implying extinct anoles may have been interacting with their Miocene environment in different ways to modern Anolis species.
Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography.

Science.gov (United States)

Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

2015-06-20

Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (p<0.001). Similarly, there was a statistically significant difference in root canal straightening after preparation between the techniques (p<0.001). Neither manual nor rotary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal.
Cleaning and shaping curved root canals: Mtwo® vs ProTaper® instruments, a lab comparison

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Kuzekanani Maryam

2009-01-01

Full Text Available Objectives: The purpose of this study was to compare root canal preparation in curved canals in molar teeth with the rotary NiTi Mtwo and ProTaper systems in terms of canal shape and smear layer. Materials and Methods: Mesiobuccal canals of 60 molar teeth with angles of curvature between 25 and 35 degrees were prepared with a torque controlled low speed engine; 30 canals for each system. Each individual instrument was used to prepare four root canals and the time required for preparation was recorded. Standardized radiographs were taken before and following instrumentation and used to determine changes in canal curvature. Results: There was no significant difference in preparation time between the two systems. No instruments separated during use. The Mtwo system gave a statistically smaller change in canal curvature and thus was better for maintaining the original shape of the root canal, with less transportation (P less than 0.05. The greatest difference was seen for maxillary molar teeth. When prepared root canals were examined by SEM there was no difference between the two systems at the coronal, middle or apical thirds. Conclusion: Overall, the results of this study suggest that Mtwo instruments are preferable for situations where canals are curved, particularly for maxillary molars.
Anal canal plasmacytoma - An uncommon presentation site

International Nuclear Information System (INIS)

Antunes, M. I.; Bujor, L.; Grillo, I. M.

2011-01-01

Background: Extramedullary plasmacytomas (EMP) are rare plasma cell tumors that arise outside the bone marrow. They are most often located in the head and neck region, but may also occur in the other locations. The lower gastrointestinal EMP represents less than 5% of all cases, and location in the anal canal is exceedingly rare. Aim: We present an exceedingly rare case of anal canal plasmacytoma, aiming to achieve a better understanding of this rare entity. Methods: We report a case of a 61-year-old man with a bulky mass in the anal canal. The lesion measured about 6 cm and invaded in all layers of the anal canal wall. The biopsy was performed and revealed a round and plasmocitoid cell population with a solid growth pattern and necrosis. The tumoral cells have express CD79a and CD138 with lambda chains. There was no evidence of disease in other locations and these features were consistent with the diagnosis of an extra-osseous plasmacytoma. The patient was submitted to conformal radiotherapy 50.4 Gy total dose, 1.8 Gy per fraction. After 24 months, the patient is asymptomatic and the lesion has completely disappeared. Conclusions: EMP accounts for approximately 3% of plasma cell malignancies. The median age is about 60 years, and the majority of patients are male. The treatment of choice for extramedullary plasmacytoma is radiation therapy in a dosage of about 50 Gy. Patients should be followed-up for life with repeated bone marrow aspiration and protein studies to detect the development of multiple myeloma. (authors)
Root canal filling using Resilon: a review.

LENUS (Irish Health Repository)

Shanahan, D J

2011-07-01

Root canal treatment is achieved by chemo-mechanical debridement of the root canal system followed by filling. The filling material \\'entombs\\' residual bacteria and acts as a barrier which prevents the entrance of oral microorganisms and reinfection of the root canal system through microleakage. However, filling with contemporary root filling materials such as gutta-percha offers limited long-term resistance to microorganisms; as a result other materials such as Resilon have been investigated as alternatives. The aim of this review was to analyse the literature to consider whether Resilon is a suitable root canal filling material. A MEDLINE and Cochrane library search including various keyword searches identified several papers which investigated or discussed Resilon or RealSeal\\/Epiphany. Analysis of the literature demonstrated that the bulk of the literature is in vitro in nature, based largely on leakage-type studies, and demonstrates a wide variety of methodologies with conflicting findings; as a result meaningful conclusions are difficult. Within the limit of these in vitro studies Resilon appears to perform adequately in comparison to gutta-percha, however, as a result of the questionable merit of such studies, it cannot presently be considered an evidence-based alternative to the current gold standard gutta-percha. It is imperative that before Resilon is considered as a replacement material, a better understanding of the physical properties of the resin sealer and the reality of the adhesive \\'monoblock\\' are elucidated. The literature also demonstrates a paucity of quality long-term clinical outcome studies which will need to be addressed before firm conclusions can be reached.
Research progress of antagonistic interactions among root canal irrigations disease

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Chen QU

2013-07-01

Full Text Available Root canal therapy is the most effective way to treat various pulposis and periapical disease. Simple mechanical apparatus can not clean root canal thoroughly, but may affect tight filling instead. It can achieve a satisfactory cleansing effect only when it is combined with a chemical solution. Irrigation fluid for root canal should possess the properties of tissue dissolution, antimicrobial, lubrication, and removal of smear layer. So far, no solution is able to fulfill all these functions. Therefore, a combined use of multiple irrigation solutions is suggested. It can not only achieve good effect in cleaning and disinfection, also it can lower the concentration of different solutions, thus reducing the side effects. Nevertheless, some experiments proved that antagonism existed among the chemicals used for irrigations. The purpose of present article is to review the antagonistic effect among the chemicals used for irrigation when they are used together for root canal treatment.
Study of polluted water mixing on sediment of Lahore canal

International Nuclear Information System (INIS)

Asim, M.

2016-01-01

People living in societies along the canals which pass through the urban areas, are adding domestic and industrial waste water and wastes into them like Lahore canal. This untreated industrial and municipal waste and contaminated water may become a risk to irrigation water quality and sediment moving in it in the form of suspended load. The results disclose that as suspended sediment concentration increases the pH value drops. Consequently it can be established from results that they are inversely related to each other but this behaviour is generally due to effect of rain water runoff. The suspended sediment content was at its highest during monsoon season. Similarly pH values varied considerably from limit of 6.5-8.4. Other water quality chemical parameters did not stray from their recommended limits. The dumping of waste water from pipes did not have any major effect on the water quality of the canal due to its less percentage to the total canal discharge. (author)

Anomaly of the facial canal in a Mondini malformation with recurrent meningitis

International Nuclear Information System (INIS)

Curtin, H.D.; Vignaud, J.; Bar, D.

1982-01-01

A patient with recurrent meningitis and congenital hearing loss was evaluated with tomography and metrizamide cisternography. Tomography showed an aberrant first portion of the facial nerve canal, while on cisternography, communication between the internal auditory canal and the dilated labyrinthine remnant was evident. The authors describe the radiographic findings and their significance and propose a mechanism for the formation of the anomalous facial nerve canal
Anomaly of the facial canal in a Mondini malformation with recurrent meningitis.

Science.gov (United States)

Curtin, H D; Vignaud, J; Bar, D

1982-07-01

A patient with recurrent meningitis and congenital hearing loss was evaluated with tomography and metrizamide cisternography. Tomography showed an aberrant first portion of the facial nerve canal, while on cisternography, communication between the internal auditory canal and the dilated labyrinthine remnant was evident. The authors describe the radiographic findings and their significance and propose a mechanism for the formation of the anomalous facial nerve canal.
Anomaly of the facial canal in a Mondini malformation with recurrent meningitis

Energy Technology Data Exchange (ETDEWEB)

Curtin, H.D. (Eye and Ear Hospital, Pittsburgh, PA); Vignaud, J.; Bar, D.

1982-07-01

A patient with recurrent meningitis and congenital hearing loss was evaluated with tomography and metrizamide cisternography. Tomography showed an aberrant first portion of the facial nerve canal, while on cisternography, communication between the internal auditory canal and the dilated labyrinthine remnant was evident. The authors describe the radiographic findings and their significance and propose a mechanism for the formation of the anomalous facial nerve canal.
Cystobasidiomycetes yeasts from Patagonia (Argentina): description of Rhodotorula meli sp. nov. from glacial meltwater.

Science.gov (United States)

Libkind, Diego; Sampaio, José Paulo; van Broock, Maria

2010-09-01

A basidiomycetous yeast, strain CRUB 1032(T), which formed salmon-pink colonies, was isolated from glacial meltwater in Patagonia, Argentina. Morphological, physiological and biochemical characterization indicated that this strain belonged to the genus Rhodotorula. Molecular taxonomic analysis based on the 26S rDNA D1/D2 domain and internal transcribed spacer region sequences showed that strain CRUB 1032(T) represents an undescribed yeast species, for which the name Rhodotorula meli sp. nov. is proposed (type strain is CRUB 1032(T)=CBS 10797(T)=JCM 15319(T)). Phylogenetic analysis showed that Rhodotorula lamellibrachii was the closest known species, which, together with R. meli, formed a separate cluster related to the Sakaguchia clade within the Cystobasidiomycetes. Additional Patagonian yeast isolates of the class Cystobasidiomycetes are also investigated in the present work.
A large Cretaceous theropod from Patagonia, Argentina, and the evolution of carcharodontosaurids

Science.gov (United States)

Novas, Fernando E.; Valais, Silvina; Vickers-Rich, Pat; Rich, Tom

2005-05-01

The Cretaceous Carcharodontosauridae is the latest clade of carnosaurs, including the largest predatory dinosaurs yet recorded. Albeit spectacular for their size, the skeletal anatomy of these theropods remains poorly-known, and their diversity was until recently restricted to two Cenomanian species: the highly derived Giganotosaurus carolinii, from southern South America, and the incompletely known Carcharodontosaurus saharicus, from northern Africa. Here we describe an older and basal member of the group, Tyrannotitan chubutensis gen. et sp. nov., from Aptian strata of Patagonia, Argentina. The new taxon gives new insights into the systematics and evolution of carcharodontosaurids and offers a better understanding of the evolution of Southern theropod faunas. We suggest that carcharodontosaurids radiated in Gondwana sharing with spinosaurids the role of top-predators until their extinction in Cenomanian Turonian times. During this interval, the diplodocoid sauropods and giant titanosaurians went extinct (probably as part of a global-scale crisis), and the smaller abelisaurid theropods took dominance, reigning until the end of the Cretaceous. Electronic Supplementary Material is available.
Hydroclimatic conditions trigger record harmful algal bloom in western Patagonia (summer 2016).

Science.gov (United States)

León-Muñoz, Jorge; Urbina, Mauricio A; Garreaud, René; Iriarte, José Luis

2018-01-22

A harmful algal bloom (HAB) of the raphidophyta alga Pseudochattonella cf. verruculosa during the 2016 austral summer (February-March) killed nearly 12% of the Chilean salmon production, causing the worst mass mortality of fish and shellfish ever recorded in the coastal waters of western Patagonia. The HAB coincided with a strong El Niño event and the positive phase of the Southern Annular Mode that altered the atmospheric circulation in southern South America and the adjacent Pacific Ocean. This led to very dry conditions and higher than normal solar radiation reaching the surface. Using time series of atmospheric, hydrologic and oceanographic data we show here that an increase in surface water temperature and reduced freshwater input resulted in a weakening of the vertical stratification in the fjords and sounds of this region. This allowed the advection of more saline and nutrient-rich waters, ultimately resulting in an active harmful algal bloom in coastal southern Chile.
Ethical and Civic Education. Difficulties during the Curricular Reform in Argentine Patagonia

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Isabelino Siede

2015-04-01

Full Text Available DOI: http://dx.doi.org/10.17227/01234870.41folios51.68 What type of ethical and civic education is effectively provided at school? This article analyzes the curricular prescriptions of Ethical and Citizenship Education in primary schools of the Argentine Patagonia, as well as its relations and contradictions with the school practices of moral education It inquires the process of definition of the area in the context of the Educational Reform in the 90s. Also, it pursuits to remake the way it was incorporated in the provincial curriculum design. Throughout focus groups and interviews to teachers from different public and private schools of three towns from de north of Santa Cruz, we analyze the descriptions and expectative of the teachers about their teaching practice in the moral area, as well as the possible causes of the differences and the contradictions between the policies of the curricular statement and educational proposals offered at school.
A comparison of the shaping ability of reciprocating NiTi instruments in simulated curved canals

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Young-Sil Yoo

2011-11-01

Full Text Available Objectives The study was to compare the shaping ability of Reciproc (VDW and WaveOne (Dentsply Maillefer instruments compared with ProTaper, Profile and hand instrument during the preparation of simulated root canals. Materials and Methods Five groups (n = 5 were established. Reciproc, WaveOne, ProTaper, Profile and K file (K-flexo file were used to prepare the resin simulated canals. A series of preoperative and postoperative images were taken by a microscope and superimposed in 2 different layers. The amount of resin removed from both the inner and the outer sides of the canal was measured to the level of 10 mm from the apical tip, with a 1 mm increment. Results The mean of resin removal from the inner canal wall was not different from the outer canal wall for Reciproc and WaveOne groups at apical third (1 - 3 mm level. There was no difference in the change of working length and maintenance of canal curvature. NiTi instruments are superior to stainless-steel K file in their shaping ability. Conclusions Within the limitation of this present study, Reciproc and WaveOne instruments maintained the original canal curvature in curved canals better than ProTaper and Profile, which tend to transport towards the outer canal wall of the curve in the apical part of the canal.
Study of seepage losses from irrigation canals using radioactive tracer technique

International Nuclear Information System (INIS)

Ahmad, M.; Tariq, J.A.; Rashid, A.; Rafiq, M.; Iqbal, N.

2004-06-01

Pakistan has an intricate irrigation system comprising a huge network of canals. A significant fraction of water in irrigation canals is lost through seepage, which is further responsible for water logging and salinity in some areas. Government is considering lining of irrigation canals to overcome this twin menace. Due to involvement of huge costs, highly pervious sections where the seepage rate is appreciably high, are needed to be identified for planning and execution of remedial actions to eliminate or minimize seepage losses. The conventional methods of measuring seepage rate from canals are limited to 'ponding' and 'inflow-outflow' methods. The ponding method is usually restricted to small canals because of the costly bulkheads and water requirement, unaffordable closure of canal, non representation of the line source and variation in the rate of seepage loss with time due to the sealing effects of fine sediments settling out. Inaccurate measurement of discharge under field conditions and complication due to diversion do not favour the inflow-outflow method. It is believed that the analytical methods represent the most accurate and convenient means of determining seepage values using accurate insitu hydraulic conductivity of the subsoil determined by radiotracer, geometry of the canal and position of the groundwater. As a practical application, radiotracer experiments were carried out at Rakh branch canal near Sukhiki, District Hafizabad (Punjab) to determine groundwater filtration velocity by single well point dilution technique using Technetium-99m (sup 99m/Tc) radioactive tracer, Hydraulic conductivity (determined from filtration velocity and hydraulic gradient) and canal parameters were used in the parametric equation of parachute curve to estimate the seepage rate. The average seepage rate was 4.05 cubic meter per day per meter length of the canal (equivalent to 3.795 cusec per million square feet or 1.157 cumec per second per million square meter of
Adaptation and penetration of resin-based root canal sealers in root canals irradiated with high-intensity lasers.

Science.gov (United States)

Moura-Netto, Cacio; Mello-Moura, Anna Carolina Volpi; Palo, Renato Miotto; Prokopowitsch, Igor; Pameijer, Cornelis H; Marques, Marcia Martins

2015-03-01

This research analyzed the quality of resin-based sealer adaptation after intracanal laser irradiation. Extracted teeth (n = 168) were root canal treated and divided into four groups, according to dentin surface treatment: no laser; Nd:YAG laser (1.5 W, 100 mJ, 15 Hz); diode laser (2.5 W in CW), and Er:YAG laser (1 W, 100 mJ, 10 Hz). The teeth were divided into four subgroups according to the sealer used: AH Plus, EndoREZ, Epiphany, and EpiphanySE. For testing the sealing after root canal obturation, the penetration of silver nitrate solution was measured, whereas to evaluate the adaptation and penetration of the sealer into the dentin, environmental scanning electron microscopy (ESEM) was used. The ESEM images were analyzed using a four-grade criteria score by three evaluators. The inter-examiner agreement was confirmed by Kappa test and the scores statistically compared by the Kruskal-Wallis' test (p laser irradiation. Nd:YAG and diode laser decreased the tracer penetration for AH Plus, whereas EndoREZ and EpiphanySE performances were affected by Nd:YAG irradiation (p laser irradiation can be used as an adjunct in endodontic treatment; however, the use of hydrophilic resin sealers should be avoided when root canals were irradiated with Nd:YAG laser.
77 FR 46285 - Drawbridge Operation Regulation; Inner Harbor Navigational Canal, New Orleans, LA

Science.gov (United States)

2012-08-03

... Operation Regulation; Inner Harbor Navigational Canal, New Orleans, LA AGENCY: Coast Guard, DHS. ACTION... Navigational Canal, mile 3.1, at New Orleans, LA. The deviation is necessary to replace the wire rope lifting... of the US 90 (Danzinger) Bridge across the Inner Harbor Navigational Canal, mile 3.1, at New Orleans...
Application of microcomputed tomography for quantitative analysis of dental root canal obturations

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Anna Kierklo

2014-03-01

Full Text Available Introduction: The aim of the study was to apply microcomputed tomography to quantitative evaluation of voids and to test any specific location of voids in tooth’s root canal obturations. Materials and Methods: Twenty root canals were prepared and obturated with gutta-percha and Tubli-Seal sealer using the thermoplastic compaction method (System B + Obtura II. Roots were scanned and three-dimensional visualization was obtained. The volume and Feret’s diameter of I-voids (at the filling/dentine interface and S-voids (surrounded by filling material were measured.Results: The results revealed that none of the scanned root canal fillings were void-free. For I-voids, the volume fraction was significantly larger, but their number was lower (P = 0.0007, than for S-voids. Both types of voids occurred in characteristic regions (P < 0.001. I-voids occurred mainly in the apical third, while S-voids in the coronal third of the canal filling.Conclusions: Within the limitations of this study, our results indicate that microtomography, with proposed semi-automatic algorithm, is a useful tools for three-dimensional quantitative evaluation of dental root canal fillings. In canals filled with thermoplastic gutta-percha and Tubli-Seal, voids at the interface between the filling and canal dentine deserve special attention due to of their periapical location, which might promote apical microleakage. Further studies might help to elucidate the clinical relevance of these results.
Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography

Science.gov (United States)

Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

2015-01-01

Background Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Material/Methods Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. Results ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (protary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal. PMID:26092929
Endodontic Treatment of a Mandibular Second Premolar with Three Roots and Three Canals

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Bonny Paul

2014-01-01

Full Text Available Complex root canal system with atypical variations is a common finding among mandibular premolars. Endodontic treatment in these teeth may not be successful due to the failure to recognise and treat multiple canals. This paper presents endodontic treatment of a mandibular second premolar with three roots and three canals.
Maxillary molars with morphologic variations of the palatal root canals: a report of four cases.

Science.gov (United States)

Holderrieth, Silke; Gernhardt, Christian Ralf

2009-07-01

The purpose of this article was to show the importance of the knowledge of the anatomy of root canals. Unusual root and root canal morphologies associated with both buccal roots of upper molars have been recorded in several studies in the literature. However, scientific information focusing on variations of the palatal root is rare. In this report, four cases are presented involving the root canal treatment of maxillary first and second molars with unusual morphologic configurations of the palatal root canals. During root canal treatment, type IV and V configurations as defined by Vertucci of the palatal canals of two first and two second maxillary molars were identified. After mechanical instrumentation, the canals were obturated. Radiologic and clinical re-evaluation showed no signs of inflammation. This report describes and discusses the possibility of different root and canal variations of the maxillary molars from a clinical point of view. Anatomic variations can occur in any tooth, and palatal roots of maxillary first and second molars are no exception. Therefore, careful examination of radiographs and internal anatomy of teeth is essential.
Ultrastructural investigation of root canal dentine surface after application of active ultrasonic method

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Mitić Aleksandar

2008-01-01

Full Text Available INTRODUCTION The basic work principle of all ultrasonic techniques is the piezoelectric effect of producing high frequency ultrasounds of small length, which are transmitted over the endodontic extensions or canal instruments into the root canal. When in contact with the tissue, ultrasonic vibrations are converted into mechanical oscillations. Ultrasonic waves and the obtained oscillations along with the synergic effect of irrigation bring about the elimination of smear layer from the root canal walls. OBJECTIVE The aim of the study was to ultrastucturally examine the effect of smear layer removal from the walls of canals by the application of the active ultrasonic method without irrigation, that is by the application of ultrasound and irrigation using distilled water and 2.5% NaOCl. METHOD The investigation comprised 35 single-canal, extracted human teeth. After removal of the root canal content, experimental samples were divided into three groups. According to the procedure required, the first group was treated by ultrasound without irrigation; the second one by ultrasound with irrigation using distilled water; and the third group was treated by ultrasound and irrigation using 2.5% NaOCl solution. The control samples were treated by machine rotating instruments (Pro-File and were rinsed by distilled water. RESULTS The obtained results showed that the ultrasonic treatment of the root canal without irrigation did not remove the smear layer. The dentine canals are masked, and big dentine particles are scattered on the intertubular dentine. The ultrasonic treatment by using irrigation with distilled water provides cleaner dentine walls and open dentine tubules but with smaller particles on the intertubular dentine. The ultrasound treatment by using irrigation with 2.5% NaOCl solution provides a clean intertubular dentine surface without a smear layer and clearly open dentine tubules. CONCLUSION Instrumentation of the root canal by application of
A single haplotype hyposensitive to light and requiring strong vernalization dominates Arabidopsis thaliana populations in Patagonia, Argentina.

Science.gov (United States)

Kasulin, Luciana; Rowan, Beth A; León, Rolando J C; Schuenemann, Verena J; Weigel, Detlef; Botto, Javier F

2017-07-01

The growing collection of sequenced or genotyped Arabidopsis thaliana accessions includes mostly individuals from the native Eurasian and N. African range and introduced North American populations. Here, we describe the genetic and phenotypic diversity, along with habitats and life history, of A. thaliana plants collected at the southernmost end of its worldwide distribution. Seed samples were harvested from plants growing in four sites within a ~3500-km 2 -area in Patagonia, Argentina, and represent the first germplasm to be collected in South America for this species. Whole-genome resequencing revealed that plants from the four sites and a Patagonia herbarium specimen collected in 1967 formed a single haplogroup (Pat), indicating that the phenotypic variation observed in the field reflected plastic responses to the environment. admixture and principal components analyses suggest that the ancestor of the Pat haplogroup either came from Italy or the Balkan/Caucasus regions of Eurasia. In the laboratory, plants from the Pat haplogroup were hyposensitive to continuous red (Rc) and shade light, with corresponding changes in the expression of phytochrome signalling genes. Pat had higher PIF3 and PIF5 and lower HY5 expression under Rc light; and lower expression of PIL1, ATHB2 and HFR1 under shade compared to Col-0. In addition, Pat plants had a strong vernalization requirement associated with high levels of FLC expression. We conclude that including Pat in studies of natural variation and in comparison with other introduced populations will provide additional information for association studies and allow for a more detailed assessment of the demographic events following colonization. © 2017 John Wiley & Sons Ltd.
Endodontic Management of a Maxillary Molar with Three Mesiobuccal Canals

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Sirisha Gundam

2014-01-01

Full Text Available It is imperative that the clinician should have comprehensive knowledge about the normal anatomy and its variations of the teeth as the deviations from the usual are very common. An increased awareness of unusual anatomy and a better understanding of the root canal system guide the clinician in accurate diagnosis and treatment of such variations in order to achieve a successful endodontic outcome. The maxillary first molar has been shown to have a wide variation in respect to the number of canals specifically noted in the mesiobuccal root. The current case report shows the successful management of a maxillary molar in which the mesiobuccal root had three canals.
The shape of the human lumbar vertebral canal

OpenAIRE

Zarzur,Edmundo

1996-01-01

Literature on the anatomy of the human vertebral column characterizes the shape of the lumbar vertebral canal as triangular. The purpose of the present study was to determine the precise shape of the lumbar vertebral canal. Ten lumbar vertebral columns of adult male cadavers were dissected. Two transverse sections were performed in the third lumbar vertebra. One section was performed at the level of the lower border of the ligamenta flava, and the other section was performed at the level of t...
Effects of irrigation solutions and Calcium hydroxide dressing on root canal treatments of periapical lesions

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Vita Nirmala

2006-03-01

Full Text Available The preparation of root canal in endodontic treatment plays an important role in treating non vital teeth with periapical lesion. Some factors influence the success of root canal treatment in short and long terms are the irrigation of root canal using antiseptic solution and the use of root canal medicament. The aim of this literature study is to determined the effect of irrigation solution and Calcium hydroxide dressing in root canal treatment of periapical lesions. The use of root canal medicament during the endodontic treatment could sterilized and decreased the number of pathogenic microorganism of root canal. An effective root canal irrigation solution must be able to dissolve organic and anorganic debris, lubricate endodontic instruments, disinfect microorganisms, non toxic and economical. The best irrigation solution has maximum antimicrobial effect with minimum toxicity. Division of calcium hydroxide into Calcium and hydroxyl ions is responsible for alkalinization of cavity, subsequently it makes the condition of cavity to be inappropriate for bacterial endotoxin in vitro as well as in vivo, and considered as the only clinically effective medicament in inactivating bacterial endotoxin. Calcium hydroxide is the only medication which has the ability to clinically inactive bacterial endotoxin in vitro in vivo and accepted as the best of root canal medication.

Nutrient Canals of the Alveolar Process as an Anatomical Feature for Age and Gender Determination

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Prashant Gupta

2017-01-01

Full Text Available Introduction: Nutrient canals are anatomic structures of the alveolar bone through which neurovascular elements transit to supply teeth and supporting structures. Dental identification using nutrient canal of the mandibular alveolar process as the most compelling anatomic feature for antemortem–postmortem radiographic comparison can be potentially used in forensic identification. Aim: The aim of the present study was to investigate the correlation between the appearance of nutrient canals as a potential clue to age and gender determination. Materials and Methods: One hundred and twenty patients, 60 males and 60 females, were selected in the 11–60-year age group. Systemic disease, especially hypertension, was ruled out in the patients. Periapical radiographs were taken from mandibular anterior cuspid central incisor region because nutrient canals are commonly observed in this area. Data obtained was analyzed by SPSS software and various statistical analysis were carried out. Results: Study revealed nutrient canals to be commonly seen in females compared to males. Males had maximum canals in the age group of 21–30-year whereas females in the age group of 31–40 years had the maximum canals. Conclusion: Significant correlation was seen between the gender and nutrient canals whereas no significant correlation existed between the age and presence of nutrient canals.
33 CFR 117.458 - Inner Harbor Navigation Canal, New Orleans.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Inner Harbor Navigation Canal, New Orleans. 117.458 Section 117.458 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Harbor Navigation Canal, New Orleans. (a) The draws of the SR 46 (St. Claude Avenue) bridge, mile 0.5...
Improvement on the Performance of Canal Network and Method of ...

African Journals Online (AJOL)

This paper presents the required improvement on the performance of canal network and method of on-farm water application systems at Tunga-Kawo irrigation scheme, Wushishi, Niger state. The problems of poor delivery of water to the farmland were identified to include erosion of canal embarkment, lack of water ...
Cone-beam computed tomography study of root and canal morphology of mandibular premolars in a western Chinese population

International Nuclear Information System (INIS)

Yu, Xuan; Guo, Bin; Li, Ke-Zeng; Zhang, Ru; Tian, Yuan-Yuan; Wang, Hu; DDS, Tao Hu

2012-01-01

Traditional radiography is limited in its ability to give reliable information on the number and morphology of root canals. The application of cone-beam computed tomography (CBCT) provides a non-invasive three-dimensional confirmatory diagnosis as a complement to conventional radiography. The aim of this study was to evaluate the root and canal morphology of mandibular premolars in a western Chinese population using CBCT scanning. The sample included 149 CBCT images comprising 178 mandibular first premolars and 178 second premolars. The tooth position, number of roots and canals, and canal configuration according to Vertucci’s classification were recorded. The results showed that 98% of mandibular first premolars had one root and 2% had two roots; 87.1% had one canal, 11.2% had two canals and 0.6% had three canals. The prevalence of C-shaped canals was 1.1%. All mandibular second premolars had one root; 97.2% had one canal and 2.2% had two canals. The prevalence of C-shaped canals was 0.6%. The prevalence of multiple canals in mandibular first premolars was mainly of Type V, and mandibular second premolars had a low rate of canal variation in this western Chinese population. Root canal bifurcation occurred at the middle or apical third in most bicanal mandibular premolars. CBCT scanning can be used in the management of mandibular premolars with complex canal morphology
Lingual Foramina and Canals of the Mandible: Anatomic Variations in a Lebanese Population

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Georges Aoun

2017-01-01

Full Text Available Objective: The aim of this study was to evaluate the mandibular lingual foramina (LF and canals and their anatomic variations using cone-beam computed tomography (CBCT technology in a Lebanese population. Materials and Methods: In this study, we analyzed CBCT images of 90 adult Lebanese patients (41 males and 49 females. We assessed the number and location of the LF. In additional, we measured: (a The distance from both the alveolar crest and the inferior border of the mandible to the LF and (b the length of the lingual canals (LCs. The data obtained was analyzed statistically using Shapiro–Wilk normality test, t-test, Chi-square, and Fisher's exact tests. Statistical significance was set at 0.05. Results: In our sample, the LF and canals were present in 93.33% of the CBCT analyzed, and the majority (76.64% was located above the genial tubercles. The distance from the foramen of the superior and the inferior LCs to the alveolar crest was 16.24 ± 2.82 mm and 25.49 ± 2.43 mm, respectively. The distance from the foramen of the superior canal to the inferior border of the mandible was 14 ± 2.32 mm. The mean length of the superior canal was 5.81 ± 1.6 mm and 4.25 ± 1.2 mm for the inferior one. There were no gender-related differences in the anatomic characteristics of the LF and canals except for the distance measured from the superior canal foramina to the alveolar crest where the measurement was significantly greater in males compared to females. Neither the number of canals nor the positions of the foramina were different between males and females. Conclusion: Within the limits of this study, we concluded that in our sample of Lebanese adults, there was substantial variability in the LF and canals anatomy and location.
A miniaturized laser-Doppler-system in the ear canal

Science.gov (United States)

Schmidt, T.; Gerhardt, U.; Kupper, C.; Manske, E.; Witte, H.

2013-03-01

Gathering vibrational data from the human middle ear is quite difficult. To this date the well-known acoustic probe is used to estimate audiometric parameters, e.g. otoacoustic emissions, wideband reflectance and the measurement of the stapedius reflex. An acoustic probe contains at least one microphone and one loudspeaker. The acoustic parameter determination of the ear canal is essential for the comparability of test-retest measurement situations. Compared to acoustic tubes, the ear canal wall cannot be described as a sound hard boundary. Sound energy is partly absorbed by the ear canal wall. In addition the ear canal features a complex geometric shape (Stinson and Lawton1). Those conditions are one reason for the inter individual variability in input impedance measurement data of the tympanic membrane. The method of Laser-Doppler-Vibrometry is well described in literature. Using this method, the surface velocity of vibrating bodies can be determined contact-free. Conventional Laser-Doppler-Systems (LDS) for auditory research are mounted on a surgical microscope. Assuming a free line of view to the ear drum, the handling of those laser-systems is complicated. We introduce the concept of a miniaturized vibrometer which is supposed to be applied directly in the ear canal for contact-free measurement of the tympanic membrane surface vibration. The proposed interferometer is based on a Fabry-Perot etalon with a DFB laser diode as light source. The fiber-based Fabry-Perot-interferometer is characterized by a reduced size, compared to e.g. Michelson-, or Mach-Zehnder-Systems. For the determination of the phase difference in the interferometer, a phase generated carrier was used. To fit the sensor head in the ear canal, the required shape of the probe was generated by means of the geometrical data of 70 ear molds. The suggested prototype is built up by a singlemode optical fiber with a GRIN-lens, acting as a fiber collimator. The probe has a diameter of 1.8 mm and a
Infrastructure performance of irrigation canal to irrigation efficiency of irrigation area of Candi Limo in Mojokerto District

Science.gov (United States)

Kisnanto, S.; Hadiani, R. R. R.; Ikhsan, C.

2018-03-01

Performance is a measure of infrastructure success in delivering the benefits corresponding it’s design implementation. Debit efficiency is a comparison between outflow debit and inflow debit. Irrigation canal performance is part of the overall performance aspects of an irrigation area. The greater of the canal performance will be concluded that the canal is increasingly able to meet the planned benefits, need to be seen its comparison between the performance and debit efficiency of the canal. The existing problems in the field that the value of the performance of irrigation canals are not always comparable to the debit efficiency. This study was conducted to describe the relationship between the performance of the canal to the canal debit efficiency. The study was conducted at Candi Limo Irrigation Area in Mojokerto Disctrict under the authority of Pemerintahan Provinsi Jawa Timur. The primary canal and secondary canal are surveyed to obtain data. The physical condition of the primary and secondary canals into the material of this study also. Primary and secondary canal performance based on the physical condition in the field. Measurement inflow and outflow debit into the data for the calculation of the debit efficiency. The instrument used in this study such as the current meter for debit measurements in the field as a solution when there is a building measure in the field were damaged, also using the meter and the camera. Permen PU No.32 is used to determine the value of the performance of the canal, while the efficiency analysis to calculate a comparison value between outflow and inflow debit. The process of data running processing by performing the measurement and calculation of the performance of the canal, the canal debit efficiency value calculation, and display a graph of the relationship between the value of the performance with the debit efficiency in each canal. The expected results of this study that the performance value on the primary canal in the
«Hay que argentinizar la Patagonia». Miradas sobre la Nación y la Ciudadanía en tiempos de cambio (1916-1930

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Ruffini, Martha

2011-12-01

Full Text Available The Goverment of Civic Radical Union (1916-1930 encourage politicals and socials transformations, that for the National territories could implyed a modification on its marginal politic. The expressions of the leadership supported this perception, but the concepts of Nation and citizenship were redefined as considering the Patagonia a place to argentinized. The argentinization was introduced as priority ,because of rural worker conflictivity,determinating the extension from politic rights to orders validity, security and social control.

El gobierno de la Unión Cívica Radical (1916-1930 alentó transformaciones políticas y sociales que para los Territorios Nacionales podían implicar la modificación de su marginalidad política. Las expresiones de la dirigencia avalaron esta percepción pero los conceptos de Nación y Ciudadanía fueron resignificados al pensar la Patagonia como espacio a «argentinizar». La argentinización del sur se presentó como prioridad debido a la conflictividad obrera-rural, condicionando la ampliación de los derechos políticos a la vigencia del orden, la seguridad y el control social.
Primer registro paleoparasitológico de Trichuris SP (nematoda, capilariidae en muestras asociadas a restos humanos del Holoceno tardío de Patagonia septentrional

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Fugassa, Martín H.

2009-01-01

Full Text Available En el marco de los estudios paleoepidemiológicos que se realizan en restos arqueológicos asignados a poblaciones de cazadores-recolectores de Patagonia, este trabajo presenta información novedosa acerca de la presencia de parásitos en muestras de sedimento de las cavidades pélvicas correspondientes a individuos que habitaron la costa norte de Patagonia durante el Holoceno Tardío. Fueron analizados 3 casos de diferente cronología y en dos de ellos, los de menor antigüedad relativa, los resultados fueron positivos para la presencia de Trichuris trichiura. Es interesante mencionar al respecto que para el período que involucra a los dos casos positivos, la información arqueológica registra un proceso de intensificación en el que se explota una mayor diversidad de fauna y se incrementan los artefactos de molienda en los sitios. Entre las posibles causas propuestas para este proceso se encuentran el aumento demográfico y/o el nucleamiento poblacional en espacios favorables que comienzan a saturarse, hecho consistente con la evidencia cultural obtenida al momento y con la presencia de Trichuris sp.
ALIMENTARY CANAL ANATOMY AND HISTOLOGY OF THE WORKER TERMITE NEOTERMES BOSEI

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LEKSONO EKOPURANTO HARIPRABOWO

2006-01-01

Full Text Available As social insects, termites live in a colony that consist of reproductive (drone and queen, and non-reproductive (soldiers and workers castes. Workers obtain their food directly from wood, humus, and other substances that contain cellulose. The objective of this study was to examine the alimentary canal of the Neotermes bosei workers. Observations of gut transverse section were carried out through the length, perimeter, and area of each alimentary canal region. The results showed that total length of N. bosei alimentary canal was 13.71+1.28 mm. The canal was divided into fore-, mid-, and hindgut which were 24, 28, and 48%, respectively of the gut total length. Two types of alimentary canal epithelial cells were found, i.e. the squamous and transitional cells. Areas covered with thick muscular tissues were crop, proventriculus, and rectum. Proventriculus was characterized with six large dentitions. There was no gastric caeca in N. bosei midgut, which commonly occurred in chewing insect. Secretory cells .wer e observed at proventriculus and ventriculus regions. Cardiac valve was found at the anterior end of ventriculus. Area with the largest outer perimeter was the rectum pouch. Enteric valve had three internal folds.
Temporal Bone Fracture Causing Superior Semicircular Canal Dehiscence

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Kevin A. Peng

2014-01-01

Full Text Available Importance. Superior semicircular canal dehiscence (SCD is a third window lesion of the inner ear causing symptoms of vertigo, autophony, tinnitus, and hearing loss. A “two-hit” hypothesis has traditionally been proposed, whereby thinly developed bone overlying the superior canal is disrupted by a sudden change in intracranial pressure. Although the symptoms of SCD may be precipitated by head injury, no previous reports have described a temporal bone fracture directly causing SCD. Observations. Two patients sustained temporal bone fractures after closed head trauma, and developed unilateral otologic symptoms consistent with SCD. In each instance, computed tomography imaging revealed fractures extending through the bony roof of the superior semicircular canal. Conclusions and Relevance. Temporal bone fractures, which are largely treated nonoperatively, have not previously been reported to cause SCD. As it is a potentially treatable entity, SCD resulting from temporal bone fracture must be recognized as a possibility and diagnosed promptly if present.
A Combined Observational and Modeling Approach to Study Modern Dust Transport from the Patagonia Desert to East Antarctica

Science.gov (United States)

Gasso, S.; Stein, A.; Marino, F.; Castellano, E.; Udisti, R.; Ceratto, J.

2010-01-01

The understanding of present atmospheric transport processes from Southern Hemisphere (SH) landmasses to Antarctica can improve the interpretation of stratigraphic data in Antarctic ice cores. In addition, long range transport can deliver key nutrients normally not available to marine ecosystems in the Southern Ocean and may trigger or enhance primary productivity. However, there is a dearth of observational based studies of dust transport in the SH. This work aims to improve current understanding of dust transport in the SH by showing a characterization of two dust events originating in the Patagonia desert (south end of South America). The approach is based on a combined and complementary use of satellite retrievals (detectors MISR, MODIS, GLAS ,POLDER, OMI,), transport model simulation (HYSPLIT) and surface observations near the sources and aerosol measurements in Antarctica (Neumayer and Concordia sites). Satellite imagery and visibility observations confirm dust emission in a stretch of dry lakes along the coast of the Tierra del Fuego (TdF) island (approx.54deg S) and from the shores of the Colihue Huapi lake in Central Patagonia (approx.46deg S) in February 2005. Model simulations initialized by these observations reproduce the timing of an observed increase in dust concentration at the Concordia Station and some of the observed increases in atmospheric aerosol absorption (here used as a dust proxy) in the Neumayer station. The TdF sources were the largest contributors of dust at both sites. The transit times from TdF to the Neumayer and Concordia sites are 6-7 and 9-10 days respectively. Lidar observations and model outputs coincide in placing most of the dust cloud in the boundary layer and suggest significant de- position over the ocean immediately downwind. Boundary layer dust was detected as far as 1800 km from the source and approx.800 km north of the South Georgia Island over the central sub-Antarctic Atlantic Ocean. Although the analysis suggests the
Maxillary lateral incisors with two canals and two separate curved roots

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Ajit George Mohan

2012-01-01

Full Text Available Variation in the roots and root canal anatomy seems to be the norm rather than an exception. For a successful endodontic treatment, a clinician should have a thorough knowledge of the internal and external dental anatomy and its variations. Maxillary lateral incisors usually exhibit single canal with a single root. In this case, clinical examination and radiographs clearly demonstrates the presence of two root canals with two separate curved roots. This case report emphasizes the need for attention during endodontic management of maxillary lateral incisors.
33 CFR 162.175 - Black Rock Canal and Lock at Buffalo, New York.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Black Rock Canal and Lock at Buffalo, New York. 162.175 Section 162.175 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Black Rock Canal and Lock at Buffalo, New York. In the Black Rock Canal and Lock, no vessel may exceed 6...
Comparison of the root canal debridement ability of two single file systems with a conventional multiple rotary system in long oval-shaped root canals: In vitro study.

Science.gov (United States)

Khoshbin, Elham; Shokri, Abbas; Donyavi, Zakieh; Shahriari, Shahriar; Salehimehr, Golsa; Farhadian, Maryam; Kavandi, Zeinab

2017-08-01

This study sought to compare the root canal debridement ability of Neolix, Reciproc and ProTaper rotary systems in long oval-shaped root canals. Eighty five extracted single-rooted human teeth with long oval-shaped single root canals were selected and divided into three experimental groups(n=25) and one control group (n= 10). Root canals were filled with Vitapex radiopaque contrast medium and prepared with Neolix, Reciproc or ProTaper systems. The control group only received irrigation. Digital radiographs were obtained at baseline and postoperatively and subjected to digital subtraction. The percentage of reduction in contrast medium was quantified at 0-5 mm and 5-10 mm distances from the apex. The data were analyzed using one-way ANOVA and t-test. The mean percentage of the contrast medium removed was not significantly different in the 0-5mm segment among the three groups ( P =0.6). In the 5-10mm segment a significant difference was found in this regard among the ProTaper and Reciproc groups ( P =0.02) and the highest mean percentage of contrast medium was removed by ProTaper. But, difference between ProTaper and Neolix as well as Neolix and Reciproc was not significant. In Neolix ( P =0.024) and Reciproc ( P =0.002) systems, the mean percentage of the contrast medium removed from the 0-5mm segment was significantly greater than that in 5-10mm segment; however, this difference was not significant in ProTaper group ( P =0.069). Neolix single-file system may be a suitable alternative to ProTaper multiple-file system in debridement of long oval shaped canals. Key words: Root Canal Preparation, Debridement, Root Canal Therapy.
First South American Agathis (Araucariaceae), Eocene of Patagonia.

Science.gov (United States)

Wilf, Peter; Escapa, Ignacio H; Cúneo, N Rubén; Kooyman, Robert M; Johnson, Kirk R; Iglesias, Ari

2014-01-01

Agathis is an iconic genus of large, ecologically important, and economically valuable conifers that range over lowland to upper montane rainforests from New Zealand to Sumatra. Exploitation of its timber and copal has greatly reduced the genus's numbers. The early fossil record of Agathis comes entirely from Australia, often presumed to be its area of origin. Agathis has no previous record from South America. We describe abundant macrofossils of Agathis vegetative and reproductive organs, from early and middle Eocene rainforest paleofloras of Patagonia, Argentina. The leaves were formerly assigned to the New World cycad genus Zamia. Agathis zamunerae sp. nov. is the first South American occurrence and the most complete representation of Agathis in the fossil record. Its morphological features are fully consistent with the living genus. The most similar living species is A. lenticula, endemic to lower montane rainforests of northern Borneo. Agathis zamunerae sp. nov. demonstrates the presence of modern-aspect Agathis by 52.2 mya and vastly increases the early range and possible areas of origin of the genus. The revision from Zamia breaks another link between the Eocene and living floras of South America. Agathis was a dominant, keystone element of the Patagonian Eocene floras, alongside numerous other plant taxa that still associate with it in Australasia and Southeast Asia. Agathis extinction in South America was an integral part of the transformation of Patagonian biomes over millions of years, but the living species are disappearing from their ranges at a far greater rate.
Reptile and rodent parasites in raptor pellets in an archaeological context: the case of Epullán Chica (northwestern Patagonia, Argentina)

Science.gov (United States)

Beltrame, María Ornela; Fernández, Fernando Julián; Sardella, Norma Haydeé

2015-07-01

Paleoparasitology is the study of parasite remains from archaeological and paleontological sites. Raptor pellets can be used as source for paleoparasitological information in archaeological sites. However, this zooarchaeological material has been scarcely studied. Epullán Chica (ECh) is an archaeological site in northwestern Patagonia. This cave yielded remains from more than 2000 years before present. The aim of this paper was to study the parasite remains found in owl pellets from the archaeological site ECh, and to discuss the paleoparasitological findings in an archaeological context. Twenty two raptor pellets were examined for parasites. The pellets were whole processed by rehydration in a 0.5% water solution of trisodium phosphate, followed by homogenization, filtered and processed by spontaneous sedimentation. Eight out of 22 bird pellets examined were positive for parasites from reptiles and rodents. Representatives of 12 parasite taxa were recorded; nine of this parasitic species were reported for the first time from ancient samples from Patagonia. This is the first time that pellets give evidences of ancient reptile parasites from archaeological contexts. It is noteworthy that Late Holocene hunter-gatherers of the upper Limay River basin, could have been exposed to some of these zoonotic parasites. Future paleoparasitological studies on owl pellets may reflect even more the parasitological diversity of all micromammal and reptile species presents in ancient times.
Evaluación de canales de bovinos machos engordados en sistemas silvopastoriles

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Jorge Iraola

2016-01-01

Full Text Available Se evaluaron 90 canales de tres ciclos productivos de bovinos machos, cebados en un sistema silvo-pastoril con inclusión de Leucaena leucocephala. Se utilizaron 30 animales por cada ciclo productivo: Cebú, Cebú mestizo y Mestizos lecheros Holstein x Cebú , con un peso vivo de sacrificio entre 399 y 420 kg. Se aplicó un modelo lineal mixto a partir de un PROC MIXED del SAS. Se consideraron, como efectos fijos: ciclo productivo, la interacción de la covarianza del peso al sacrificio con el ciclo productivo; y como aleatorios: el efecto del animal anidado dentro de ciclo productivo y el error residual. Se estudiaron los indicadores: peso sacrificio, peso de la canal caliente, peso de la canal fría, carne, hueso y grasa, el rendimiento de todas las partes de la canal. Se realizaron análisis de regresiones lineales relacionadas con el rendimiento cárnico con el programa estadístico INFOSTAT. Se encontraron diferencias (P<0.05 entre ciclos productivos respecto de la canal y las demás partes. El tercer ciclo presentó el mayor porcentaje de hueso en la canal y menor rendimiento cárnico. Todos los ciclos productivos manifestaron un comportamiento lineal favorable en silvopastoreo con leucaena. Se concluye que los ciclos 1 y 2 tuvieron mejor comportamiento en canal con respecto al tercer ciclo con los animales Mestizos lecheros; lo cual está asociado al plano de alimentación y el peso de sacrificio que condicionaron el rendimiento cárnico.
Micro-Computed Tomography Analysis of the Root Canal Morphology of Palatal Roots of Maxillary First Molars.

Science.gov (United States)

Marceliano-Alves, Marília; Alves, Flávio Rodrigues Ferreira; Mendes, Daniel de Melo; Provenzano, José Claudio

2016-02-01

A thorough knowledge of root canal anatomy is critical for successful root canal treatments. This study evaluated the internal anatomy of the palatal roots of maxillary first molars with micro-computed tomography (microCT). The palatal roots of extracted maxillary first molars (n = 169) were scanned with microCT to determine several anatomic parameters, including main canal classification, lateral canal occurrence and location, degree of curvature, main foramen position, apical constriction presence, diameters 1 and 2 mm from the apex and 1 mm from the foramen, minor dentin thickness in those regions, canal volume, surface area, and convexity. All canals were classified as Vertucci type I. The cross sections were oval in 61% of the canals. Lateral canals were found in 25% of the samples. The main foramen did not coincide with the root apex in 95% of the cases. Only 8% of the canals were classified as straight. Apical constriction was identified in 38% of the roots. The minor and major canal diameters and minor dentin thickness were decreased near the apex. The minor dentin thickness 1 mm from the foramen was 0.82 mm. The palatal canals exhibited a volume of 6.91 mm(3) and surface area of 55.31 mm(2) and were rod-shaped. The root canals of the palatal roots were classified as type I. However, some factors need to be considered during the treatment of these roots, including the frequent ocurrence of moderate/severe curvatures, oval-shaped cross-sections, and lateral canals, noncoincidence of the apical foramen with the root apex, and absence of apical constriction in most cases. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Endodontic management of mandibular first molars with mid mesial canal: A case series.

Science.gov (United States)

Nagmode, Pradnya Sunil; Patel, Ankit Vasant; Satpute, Archana Bhaskar; Gupta, Pooja L

2017-01-01

The purpose of this study is to demonstrate the importance of knowledge of the internal anatomy of root canals for the success of endodontic treatment. Lack of knowledge of anatomic variations and their characteristics in different teeth has been pointed out as one of the main cause of endodontic therapy failure. Dental operating microscope plays a key role in the identification of canal and success of endodontic treatment. This case series describes the endodontic treatment of mandibular first molars with extra root canals, evaluate the occurrence of this extra canal, and discuss the importance of their identification and treatment.

Evaluation of Root and Canal Morphology of Mandibular First Molars: A Clearing Method in an Iranian Population

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Shirkavand

2016-07-01

Full Text Available Background Successful endodontic treatment is dependent on the knowledge of root canal anatomy. Objectives This study aims to investigate the root canal anatomy of mandibular first molars in an Iranian population. Materials and Methods One hundred human mandibular first molars were collected and stored in 5.25% NaOCl. Radiographic images of the teeth were taken in mesial, distal, and buccal aspects using digital radiography. The root numbers were recorded, and the teeth were covered with lacquer. Access cavities were prepared, pulp tissue was dissolved, the apex was covered with liquid glue, and the root canals were injected with methylene blue. Decalcification of the teeth meant they were kept in 10% nitric acid, and final dehydration meant they were kept in 100% Isopropyl alcohol for 72 hours and rendered clear by immersion in methyl salicylate. The number of root canals per tooth, the number of canals per root, and canal configuration in each tooth were recorded. Results Ninety-nine of the 100 teeth had two roots and the other had three roots. The teeth were classified based on the number of canals; there were 2% with two canals, 59% with three canals, and 39% with four canals. Based on the Vertucci classification, the most prevalent canal configurations in the mesial root were types II and IV, and type I in the distal root. Conclusions The most common root morphology is the two rooted morphology with three canals. Both the mesial and distal roots show wide variations in canal anatomy with type IV and type I canal configuration predominating in the mesial and distal roots, respectively. Iranian mandibular first molar teeth exhibit features close to the average Caucasian, Jordanian, and Kuwaiti’s root and canal morphology.
Radiographic prevalence of root canal ramifications in a sample of root canal treatments in a Brazilian Dental School Prevalência radiográfica de ramificações do canal radicular em uma amostra de tratamentos endodônticos em uma Faculdade de Odontologia Brasileira

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Iadasa de Quadros

2007-06-01

Full Text Available The aim of this study was to radiographically investigate the presence of root canal ramifications found after endodontic treatment, and to determine any relationship between their presence and the type of the auxiliary chemical substance used. The study evaluated 1,470 endodontic treatments performed by final year undergraduate students at the Dental School of Piracicaba, State University of Campinas (UNICAMP, SP, Brazil, during the period from 1998 to 2000. The X-rays taken during treatment were evaluated in order to establish the presence of ramifications of the root canal system. The initial X-ray did not show the presence of any canal ramifications. After filling, X-rays showed only 3 ramification types: 3.06% of lateral canals, 2.99% of apical deltas, and 0.1% of interradicular canals. The maxillary premolars showed the highest number of lateral canals (n = 13, followed by mandibular premolars (n = 10 and maxillary incisors (n = 10. Apical deltas were mostly found in mandibular molars (n = 14, followed by maxillary incisors (n = 9. Only mandibular molars had interradicular canals. The detection of ramifications increased with the use of EDTA. However, no statistically significant relationship was found between the type of auxiliary chemical substance used and the number of root canal ramifications detected after root canal filling. It was concluded that the frequency of root canal ramifications found radiographically was low in treatments performed by undergraduate students.O objetivo deste estudo foi investigar radiograficamente a presença de ramificações do canal radicular encontrada depois do tratamento endodôntico, e determinar qualquer relação entre a presença destas e do tipo de substância química auxiliar usada. O estudo avaliou 1.470 tratamentos endodônticos executados pelos estudantes do último ano da Faculdade de Odontologia de Piracicaba, Universidade Estadual de Campinas (UNICAMP, SP, Brasil, no período de 1998 a
Complete atrioventricular canal.

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Calabrò, Raffaele; Limongelli, Giuseppe

2006-04-05

Complete atrioventricular canal (CAVC), also referred to as complete atrioventricular septal defect, is characterised by an ostium primum atrial septal defect, a common atrioventricular valve and a variable deficiency of the ventricular septum inflow. CAVC is an uncommon congenital heart disease, accounting for about 3% of cardiac malformations. Atrioventricular canal occurs in two out of every 10,000 live births. Both sexes are equally affected and a striking association with Down syndrome was found. Depending on the morphology of the superior leaflet of the common atrioventricular valve, 3 types of CAVC have been delineated (type A, B and C, according to Rastelli's classification). CAVC results in a significant interatrial and interventricular systemic-to-pulmonary shunt, thus inducing right ventricular pressure and volume overload and pulmonary hypertension. It becomes symptomatic in infancy due to congestive heart failure and failure to thrive. Diagnosis of CAVC might be suspected from electrocardiographic and chest X-ray findings. Echocardiography confirms it and gives anatomical details. Over time, pulmonary hypertension becomes irreversible, thus precluding the surgical therapy. This is the reason why cardiac catheterisation is not mandatory in infants (less than 6 months) but is indicated in older patients if irreversible pulmonary hypertension is suspected. Medical treatment (digitalis, diuretics, vasodilators) plays a role only as a bridge toward surgery, usually performed between the 3rd and 6th month of life.
Complete atrioventricular canal

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Limongelli Giuseppe

2006-04-01

Full Text Available Abstract Complete atrioventricular canal (CAVC, also referred to as complete atrioventricular septal defect, is characterised by an ostium primum atrial septal defect, a common atrioventricular valve and a variable deficiency of the ventricular septum inflow. CAVC is an uncommon congenital heart disease, accounting for about 3% of cardiac malformations. Atrioventricular canal occurs in two out of every 10,000 live births. Both sexes are equally affected and a striking association with Down syndrome was found. Depending on the morphology of the superior leaflet of the common atrioventricular valve, 3 types of CAVC have been delineated (type A, B and C, according to Rastelli's classification. CAVC results in a significant interatrial and interventricular systemic-to-pulmonary shunt, thus inducing right ventricular pressure and volume overload and pulmonary hypertension. It becomes symptomatic in infancy due to congestive heart failure and failure to thrive. Diagnosis of CAVC might be suspected from electrocardiographic and chest X-ray findings. Echocardiography confirms it and gives anatomical details. Over time, pulmonary hypertension becomes irreversible, thus precluding the surgical therapy. This is the reason why cardiac catheterisation is not mandatory in infants (less than 6 months but is indicated in older patients if irreversible pulmonary hypertension is suspected. Medical treatment (digitalis, diuretics, vasodilators plays a role only as a bridge toward surgery, usually performed between the 3rd and 6th month of life.
Shaping ability of 4 different single-file systems in simulated S-shaped canals.

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Saleh, Abdulrahman Mohammed; Vakili Gilani, Pouyan; Tavanafar, Saeid; Schäfer, Edgar

2015-04-01

The aim of this study was to compare the shaping ability of 4 different single-file systems in simulated S-shaped canals. Sixty-four S-shaped canals in resin blocks were prepared to an apical size of 25 using Reciproc (VDW, Munich, Germany), WaveOne (Dentsply Maillefer, Ballaigues, Switzerland), OneShape (Micro Méga, Besançon, France), and F360 (Komet Brasseler, Lemgo, Germany) (n = 16 canals/group) systems. Composite images were made from the superimposition of pre- and postinstrumentation images. The amount of resin removed by each system was measured by using a digital template and image analysis software. Canal aberrations and the preparation time were also recorded. The data were statistically analyzed by using analysis of variance, Tukey, and chi-square tests. Canals prepared with the F360 and OneShape systems were better centered compared with the Reciproc and WaveOne systems. Reciproc and WaveOne files removed significantly greater amounts of resin from the inner side of both curvatures (P files was significantly faster compared with WaveOne and F360 files (P file instruments were safe to use and were able to prepare the canals efficiently. However, single-file systems that are less tapered seem to be more favorable when preparing S-shaped canals. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Using residual tritiated water from Cernavoda NPP to study Danube - Black Sea Canal hydrodynamics

International Nuclear Information System (INIS)

Varlam, C.; Stefanescu, I.; Lazar, R.; Varlam, M.; Patrascu, V.; Bucur, C.; Bobric, E.

2003-01-01

By benefiting of Cernavoda NPP's location in the neighbourhood of Danube - Black Sea Canal one suggests extending the area of interest along this canal particularly to use the residual tritiated water from this CANDU type reactor as tracing means in the study of canal's hydrodynamics. This canal appears to be ideal for such a study because releases in normal operation of NPP are occasional. The tritiated water can be used for simulating the transport and dispersion of soluble pollutants because it has the same physical characteristics as the usual water. By measuring response curves produced at injecting a known amount of tracer one can developed an efficient method for estimating: the soluble pollutant velocity along the canal; attenuation rate of concentration peak as a function of time as well as the time required by the propagation front of the soluble pollutant to reach a given point along the canal. In this work the calculation of the mixture length as a function of the particular characteristics of the canal is presented as well as different experimental formulas. Also the reference level of tritium concentration in the investigated area is established for future experiments
Effect of canal length and curvature on working length alteration with WaveOne reciprocating files.

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Berutti, Elio; Chiandussi, Giorgio; Paolino, Davide Salvatore; Scotti, Nicola; Cantatore, Giuseppe; Castellucci, Arnaldo; Pasqualini, Damiano

2011-12-01

This study evaluated the working length (WL) modification after instrumentation with WaveOne Primary (Dentsply Maillefer, Ballaigues, Switzerland) reciprocating files and the incidence of overinstrumentation in relation to the initial WL. Thirty-two root canals of permanent teeth were used. The angles of curvature of the canals were calculated on digital radiographs. The initial WL with K-files was transferred to the matched WaveOne Primary reciprocating files. After glide paths were established with PathFile (Dentsply Maillefer, Ballaigues, Switzerland), canals were shaped with WaveOne Primary referring to the initial WL. The difference between the postinstrumentation canal length and the initial canal length was analyzed by using a fiberoptic inspection microscope. Data were analyzed with a balanced 2-way factorial analysis of variance (P < .05). Referring to the initial WL, 24 of 32 WaveOne Primary files projected beyond the experimental apical foramen (minimum-maximum, 0.14-0.76 mm). A significant decrease in the canal length after instrumentation (95% confidence interval ranging from -0.34 mm to -0.26 mm) was detected. The canal curvature significantly influenced the WL variation (F(1) = 30.65, P < .001). The interaction between the initial canal length and the canal curvature was statistically significant (F(2) = 4.38, P = .014). Checking the WL before preparation of the apical third of the root canal is recommended when using the new WaveOne NiTi single-file system. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Partial absence of the posterior semicircular canal in Alagille syndrome: CT findings

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Koch, Bernadette; Egelhoff, John; Benton, Corning [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati (United States); Goold, Amy [Tripler Army Medical Center, Family Practice, Honolulu, HI (United States)

2006-09-15

We report a case of bilateral partial absence of the posterior semicircular canals (with normal lateral semicircular canals) imaged with CT in a patient with Alagille syndrome. Similar histologic findings have been reported in the pathology literature. This association has been previously reported only for Waardenburg syndrome in the imaging literature. We review the imaging findings and embryology of the semicircular canals, and suggest that this abnormality is specific to patients with Alagille or Waardenburg syndrome. (orig.)
Partial absence of the posterior semicircular canal in Alagille syndrome: CT findings

International Nuclear Information System (INIS)

Koch, Bernadette; Egelhoff, John; Benton, Corning; Goold, Amy

2006-01-01

We report a case of bilateral partial absence of the posterior semicircular canals (with normal lateral semicircular canals) imaged with CT in a patient with Alagille syndrome. Similar histologic findings have been reported in the pathology literature. This association has been previously reported only for Waardenburg syndrome in the imaging literature. We review the imaging findings and embryology of the semicircular canals, and suggest that this abnormality is specific to patients with Alagille or Waardenburg syndrome. (orig.)
Shaping ability of NT Engine and McXim rotary nickel-titanium instruments in simulated root canals. Part 1.

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Thompson, S A; Dummer, P M

1997-07-01

The aim of this study was to determine the shaping ability of NT Engine and McXim nickel-titanium rotary instruments in simulated root canals. In all, 40 canals consisting of four different shapes in terms of angle and position of curvature were prepared by a combination of NT Engine and McXim instruments using the technique recommended by the manufacturer. Part 1 of this two-part report describes the efficacy of the instruments in terms of preparation time, instrument failure, canal blockages, loss of canal length and three-dimensional canal form. Overall, the mean preparation time for all canals was 6.01 min, with canal shape having a significant effect (P Engine and McXim instruments prepared canals rapidly, with few deformations, no canal blockages and with minimal change in working length. The three-dimensional form of the canals demonstrated good flow and taper characteristics.
Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals.

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Boutsioukis, C; Verhaagen, B; Walmsley, A D; Versluis, M; van der Sluis, L W M

2013-11-01

(i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall contact on file oscillation. File-to-wall contact was measured during ultrasonic activation of the irrigant performed by 15 trained and 15 untrained participants in two metal root canal models. Results were analyzed by two 5-way mixed-design anovas. The level of significance was set at P root canal (P root canal (P irrigant activation. Therefore, the term 'Passive Ultrasonic Irrigation' should be amended to 'Ultrasonically Activated Irrigation'. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.
Microbiological indicators of water quality in the Xochimilco canals, Mexico City.

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Juárez-Figueroa, Luis Alfredo; Silva-Sánchez, Jesús; Uribe-Salas, Felipe Javier; Cifuentes-García, Enrique

2003-01-01

To quantify microbiology indicators of fecal contamination in the effluents of two waste water treatment plants and in samples collected in several canals in Xochimilco. A cross sectional study was performed. Ten sites, 5 from plant effluents and 5 from canals, were selected for sampling during November and December 2001. Fecal coliforms and enterococci were quantified by membrane filtration, male specific (F+) and somatic coliphages by double agar layer technique, and Cryptosporidium oocysts and Giardia cysts by concentration with Envirocheck filter followed by immunofluorescence microscopy quantification. The average of organisms counts from effluents and canal water were compared with t Student test. Treated water discharge in canals showed a low count of Fecal Coliforms (average 40.4/100 ml), enterococci (average 58.8/100 ml) and Cryptosporidium oocysts (average 13.2/100 l), while coliphages and Giardia cyst rendered higher counts (average 1467.5/100 ml and 1199.8/100 l, respectively) suggesting the water treatment methods could fail to remove these agents. A significant lower count of Giardia cysts (average 45/100 l) and no Cryptosporidium oocysts were found in irrigation canals, which suggests a natural clearance of these pathogens. Strains of Escherichia coli isolated in one of the canals contaminated with sewage had antimicrobial multi-resistance that was transferred by conjugation suggesting that resistance is encoded in a plasmid potentially transferable to other pathogenic bacteria. Cost effective and culturally acceptable waste treatment methods will require careful planning and consultation if they are to be adopted and mantained by local populations.
Frequency of enterococcus faecalis in saliva and root canals with treatment failure

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Khan, I.; Shan, T.; Manzoor, M.A.

2015-01-01

To compare the frequency of E. faecalis in the saliva and root canals of teeth associated with apical periodontitis due to endodontic treatment failure in the same patient. Study Design: Cross-sectional comparative study. Place and Duration of Study: Samples were collected from Operative Dentistry Department, AFID, while laboratory processing was done at AFIP, Rawalpindi. Study duration was one year. Patients and Methods: Fifty patients, both males and females with failed endodontic treatment were selected. Saliva and root canal samples were collected from each patient, inoculated on MacKonkey agar plate and incubated at 35-37 degree C for 48 hrs. E. faecalis colonies were identified by colony morphology, gramstain, catalase, bile asculin test, arabinose fermentation and growth in 6% NaCl nutrient broth. Results: The frequency of E. faecalis in saliva was 34% and in root canal it was 58%. Frequency between the presence of E. faecalis in root canals and saliva was found to be statistically different (p = 0.001). Conclusion: The presence of E. faecalis in root canal was not associated with their presence in saliva. (author)
Frequency of enterococcus faecalis in saliva and root canals with treatment failure

International Nuclear Information System (INIS)

Shan, T.; Manzoor, M.A.; Hussain, W.

2014-01-01

To compare the frequency of E.faecalis in the saliva and root canals of teeth associated with apical periodontitis due to endodontic treatment failure Study. Design: Cross-sectional comparative. Place and Duration of Study: Samples were collected from Operative Dentistry department, AFID, while laboratory processing was done at AFIP, Rawalpindi. Duration of this study was one year. Patients and Method: Fifty patients, both males and females with failed endodontic treatment were selected. Saliva and root canal samples were collected from each patient, inoculated on MacKonkey agar plate and incubated at 35-370 C for 48 hours. E.faecalis colonies were identified by colony morphology, Gram stain, catalase, bile asculin test, arabinose fermentation and growth in 6% NaCl nutrient broth. Results: The frequency of E.faecalis in saliva was 34% and 58% in root canal samples. Frequency of the presence of E.faecalis in root canals and saliva was found to be statistically different (p=0.000). Conclusion: The presence of E.faecalis in root canal was not associated with their presence in saliva. (author)
Visibility of the mandibular canal and the mental foramen in panoramic radiography

International Nuclear Information System (INIS)

Jeong, Seon Jin; Choi, Eui Hwan; Kim, Jae Duk

2001-01-01

To determine the head position that the superior border of the mandibular canal as well as mental foramen can be more clearly visualized in panoramic radiography. Ten dry mandibles were radiography bilaterally using PM 2002 CC panoramic machine. A 20 mm thick aluminium filter was added to the slit collimator to obtain radiographs with acceptable density. The specimens were tilted by 2, 4, 6, 8 and 10 degrees downward with and without radiopaque markers. Radiopaque markers were inserted into the mandibular canals and the mental canals of each side of the specimens to serve as reference image when assessing the radiographs. The obtained results were analyzed statistically. Mandibular canals were significantly more clearly visible in the radiographs with 4 and 6 degree downward position on both sides (P<0.05). Mental foramen were significantly more clearly visible in the was not significant difference between right and left sides. Panoramic radiographs with 4 to 6 degree downward tilting could be valuable in locating the mandibular canal as well as the mental foramen
[Bond strengths of absorbable polylactic acid root canal post with three different adhesives].

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Pan, Hui; Cheng, Can; Hu, Jia; Liu, He; Sun, Zhi-hui

2015-12-18

To find absorbable adhesives with suitable bonding properties for the absorbable polylactic acid root canal post. To test and compare the bond strengths of absorbable polylactic acid root canal post with three different adhesives. The absorbable polylactic acid root canal posts were used to restore the extracted teeth, using 3 different adhesives: cyanoacrylates, fibrin sealant and glass ionomer cement. The teeth were prepared into slices for micro-push-out test. The bond strength was statistically analyzed using ANOVA. The specimens were examined using microscope and the failure mode was divided into four categories: cohesive failure between absorbable polylactic acid root canal posts and adhesives, cohesive failure between dentin and adhesives, failure within the adhesives and failure within the absorbable polylactic acid root canal posts. The bond strength of cyanoacrylates [(16.83 ± 6.97) MPa] and glass ionomer cement [(12.10 ± 5.09) MPa] were significantly higher than fibrin sealant [(1.17 ± 0.50) MPa], Padhesives was 25.0%, the cohesive failure between the dentin and the adhesives was 16.7%, the failure within the adhesives was 33.3%, and the failure within the absorbable polylactic acid root canal posts was 25.0%. In the group of fibrin sealant, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 66.7%, the cohesive failure between the dentin and the adhesives was 22.2%, the failure within the adhesives was 11.1%. In the group of glass ionomer cement, the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives was 87.5%, the failure within the adhesives was 12.5%. The major failure mode in fibrin sealant and glass ionomer cement was the cohesive failure between the absorbable polylactic acid root canal posts and the adhesives. No major failure modes were found in the group of cyanoacrylates. The bond strength of fibrin sealant is low, which cannot meet the requirement of
Quantitative three-dimensional analysis of root canal curvature in maxillary first molars using micro-computed tomography.

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Lee, Jong-Ki; Ha, Byung-Hyun; Choi, Jeong-Ho; Heo, Seok-Mo; Perinpanayagam, Hiran

2006-10-01

In endodontic therapy, access and instrumentation are strongly affected by root canal curvature. However, the few studies that have actually measured curvature are mostly from two-dimensional radiographs. The purpose of this study was to measure the three-dimensional (3D) canal curvature in maxillary first molars using micro-computed tomography (microCT) and mathematical modeling. Extracted maxillary first molars (46) were scanned by microCT (502 image slices/tooth, 1024 X 1024 pixels, voxel size of 19.5 x 19.5 x 39.0 microm) and their canals reconstructed by 3D modeling software. The intersection of major and minor axes in the canal space of each image slice were connected to create an imaginary central axis for each canal. The radius of curvature of the tangential circle was measured and inverted as a measure of curvature using custom-made mathematical modeling software. Root canal curvature was greatest in the apical third and least in the middle third for all canals. The greatest curvatures were in the mesiobuccal (MB) canal (0.76 +/- 0.48 mm(-1)) with abrupt curves, and the least curvatures were in the palatal (P) canal (0.38 +/- 0.34 mm(-1)) with a gradual curve. This study has measured the 3D curvature of root canals in maxillary first molars and reinforced the value of microCT with mathematical modeling.
Micro-computed Tomographic Analysis of Mandibular Second Molars with C-shaped Root Canals.

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Amoroso-Silva, Pablo Andrés; Ordinola-Zapata, Ronald; Duarte, Marco Antonio Hungaro; Gutmann, James L; del Carpio-Perochena, Aldo; Bramante, Clovis Monteiro; de Moraes, Ivaldo Gomes

2015-06-01

The goal of the present study was to evaluate the morphometric aspects of the internal anatomy of the root canal system of mandibular second molars with C-shaped canals. Fifty-two extracted second mandibular molars with C-shaped canals, fused roots, and radicular grooves were selected from a Brazilian population. The samples were scanned with a micro-computed tomographic scanner at a voxel size of 19.6 μm. The root canal cross sections were recorded as C1, C2, C3, and C4 root canal configurations according to the modified Melton classification. Morphometric parameters, including the major and minor diameters of the root canals, the aspect ratio, the roundness, and the tridimensional configuration (merging, symmetric, and asymmetric), were evaluated. The 3-dimensional reconstruction images of the teeth indicated an even distribution within the sample. The analysis of the prevalence of the different cross-sectional configurations of the C-shaped molars revealed that these were predominantly of the C4 and C3 configurations (1 mm from the apex) and the C1 and C2 configurations in the cervical third. According to the morphometric parameters, the C1 and the distal aspect of the C2 configurations exhibited the lowest roundness values and higher values for the area, major diameter, and aspect ratio in the apical third. Mandibular molars with C-shaped root canals exhibited similar distributions of symmetric, asymmetric, and merging type canals. The C1 configuration and the distal aspect of the C2 configuration exhibited the highest area values, low roundness values, and large apical diameters. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.
Role of the confinement of a root canal on jet impingement during endodontic irrigation

NARCIS (Netherlands)

Verhaagen, B.; Boutsioukis, C.; Heijnen, G. L.; van der Sluis, L. W. M.; Versluis, M.

2012-01-01

During a root canal treatment the root canal is irrigated with an antimicrobial fluid, commonly performed with a needle and a syringe. Irrigation of a root canal with two different types of needles can be modeled as an impinging axisymmetric or non-axisymmetric jet. These jets are investigated
Surveillance of microbial indicators and physicochemical parameters to investigate pollution status of Lahore canal

International Nuclear Information System (INIS)

Tahir, A.; Kanwal, F.; Mateen, B.

2011-01-01

The Lahore canal is an important watershed in Lahore. The present study was conducted to monitor pollution load of Lahore canal. Surface water was collected from the middle of the canal at four different sites, and analysed for physicochemical parameters (temperature, pH, EC, DO, BOD/sub 5/, turbidity, nitrates, phosphates) and microbial load (bacteria (TVC), total coliform and fungi). Water quality parameters were monitored from May to August at four sites along 17Km long patch. Surface water was collected in the middle of the canal. The results were compared with IWQ guidelines proposed by WWF, Pakistan. Pollution load of Lahore Canal revealed an alarming situation. Water can be used for the irrigation purpose, but only with advanced treatment. (author)

Cone Beam Computed Tomographic Evaluation and Diagnosis of Mandibular First Molar with 6 Canals

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Shiraz Pasha

2016-01-01

Full Text Available Root canal treatment of tooth with aberrant root canal morphology is very challenging. So thorough knowledge of both the external and internal anatomy of teeth is an important aspect of root canal treatment. With the advancement in technology it is imperative to use modern diagnostic tools such as magnification devices, CBCT, microscopes, and RVG to confirm the presence of these aberrant configurations. However, in everyday endodontic practice, clinicians have to treat teeth with atypical configurations for root canal treatment to be successful. This case report presents the management of a mandibular first molar with six root canals, four in mesial and two in distal root, and also emphasizes the use and importance of Cone Beam Computed Tomography (CBCT as a diagnostic tool in endodontics.
Knowledge of General Dentists of Kermanshah about Root Canal Therapy in 2012

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Roohollah Sharifi

2014-04-01

Full Text Available Introduction: The present study was conducted to analyze the knowledge of general dentists of Kermanshah about root canal therapy in 2012. Methods: In this descriptive cross-sectional study, a two-part questionnaire was designed and given to 93 general dentists in Kermanshah to complete. The first part of the questionnaire comprised of personal and professional information of the participant dentists and the second part of the questionnaire determined the awareness of the dentists about root canal therapy. Data were analyzed by SPSS software (version 20 using Pearson correlation coefficient, one-way analysis of variance (ANOVA and independent t-test. Results: A total of 84 dentists with the mean age of 39.3±7.1 completed the questionnaires. The mean for 12 correct responses was 63.3%. The highest number of correct responses (86.2% belonged to using proper intra-canal medication (calcium hydroxide and the lowest number of correct responses (41.4% was associated with the number of root canals in maxillary first molar (four canals. There was a reverse correlation between awareness and work experience (P=0.002, r=-0.337. Also, participation in retraining courses did not have significant impact on the knowledge of the dentists (P =0.82. Conclusion: General dentists have average knowledge about root canal therapy. Higher quality regular training is recommended to promote the knowledge of the dentists about endodontic therapies.
Radioactivity of the Bega sediment-case study of a contaminated canal

International Nuclear Information System (INIS)

Bikit, I.; Varga, E.; Conkic, Lj.; Slivka, J.; Mrda, D.; Curcic, S.; Zikic-Todorovic, N.; Veskovic, M.

2005-01-01

The Bega canal is one among many heavily polluted canals in Vojvodina (the northern province of Serbia and Montenegro). In the framework of the revitalization of this canal, the radionuclide content of the sediment was investigated in order to support the safe deposition after excavation. It was found that, in comparison with the Danube sediment and Vojvodina soil, the Bega sediment is contaminated with 238 U and 137 Cs. The origin of this contamination is discussed. No traces of contamination by nuclear power plants in the region were found, while the presence of technologically enhanced, natural occurring radioactive materials (TENORM) was proved
In Vitro Comparative Study of the Working Length Determination with Radiovisiography and Conventional Radiography in Dilacerated Canals

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Ali Bagherpour

2015-06-01

Full Text Available Introduction: The aim of this study was to compare digital and conventional radiography in determining the working length of dilacerated canals.Methods: Thirty nine human extracted single-rooted teeth with root curvature more than 35 degrees were included in this study. After access preparation, a file was inserted into the canal and advanced until the file tip was visualized at the foramen. With measurement of the file length using a millimeter ruler, true canal length was determined for each canal. Then, teeth were mounted in acrylic blocks and canal length was estimated by using on-screen digital radiography with both 3- and 6-clicks measurement and from conventional radiography by conforming a preserved file on the image of the root canal.Results: There were no significant differences in measurement accuracy between the true canal length and conventional radiographic length, but there were significant difference between both digital radiographic techniques with true canal length. There was no significant correlation between root curvature and canal length estimation error of studied methods.Conclusion: In dilacerated canals, the accuracy of determination of working length by using conventional radiography is higher than digital radiography
[Benign paroxysmal positional vertigo of the anterior semicircular canal: clinical aspects and treatment].

Science.gov (United States)

Lorin, P

2005-01-01

To describe the videonystagmographic characteristics and the treatment of the patients reached with a canalolithiasis or a cupulolithiasis of the anterior semicircular canal. Retrospective study concerning patients treated for a Benign Paroxysmal Positional Vertigo (BPPV) of the anterior semicircular canal. Each patient after analysis under videonystagmoscopy (VNS) and under videonystagmography (VNG) was treated by maneuvers. On 462 observations of typical BPPV 6 cases of VPPB of the anterior semicircular canal were treated concerning 5 patients (1.3%). The BPPV of the anterior semicircular canal are rare. We modified our method of diagnosis, and our therapeutic techniques could be validated with the help of the two-dimensional videonystagmography.
Evaluation of interference of calcium hydroxide-based intracanal medication in filling root canal systems.

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Vilela, Deyla Duarte; Neto, Manoel Matos; Villela, Alexandre Mascarenhas; Pithon, Matheus Melo

2011-09-01

To evaluate the interference of the intracanal medication Calen® (SSWhite, Sao Paulo, Brazil) on the filling of simulated lateral canals. Twenty human anterior teeth were used. Before the endodontic filling procedures the access of cavity was made, and after this root canals were made in all the teeth to simulate the presence of lateral canals. After preparation, the teeth were randomly divided into two groups (n=10). In group I, the root canal system was filled directly after chemicalmechanical preparation; in group II, endodontic treatment was performed in multiple sessions, and after preparation the calcium hydroxide-based intracanal medication Calen® was inserted. After the period of 7 days, the root canals were vigorously irrigated and then they were filled. Next, the teeth were radiographed to verify the quality of the filling. The results demonstrated that the teeth treated in a single session, without calcium hydroxide medication, presented 47 canals out of 60 with radiographic evidence of filling, whereas the teeth in which intracanal medication was used, only 07 presented a radiographic image compatible with filling (p < 0.05). The use of the calcium hydroxide-based medication Calen made it difficult to obtain a hermetic filling of the root canal system. The clinical significance of this work basing on the fact that once the dentist knowing that property obliteration of calcium hydroxide can be taken care when they are used in the presence of lateral canals.
Prevalence of two root canals in human mandibular anterior teeth in an Iranian population

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Saeed Rahimi

2013-01-01

Full Text Available Background: Complete debridement and obturation of the root canal system is a key factor in successful endodontic treatment and the operator should therefore have thorough knowledge of the root canal morphology of the teeth. Numerous studies have been carried out to investigate the canal configuration of different tooth types in various populations. Aims: The aim of the present study was to investigate the internal anatomy of mandibular incisors and canines in an Iranian population. Materials and Methods: A total of 463 mandibular anterior teeth, including 186 centrals, 128 laterals, and 149 canines, were examined. A standard clearing technique was used to make the teeth transparent. India ink was injected into the canals of the teeth and the samples were examined with a magnifying glass. The root canal configurations were categorized according to the Vertucci classification. Results: All the incisors in this study had one root, and 12.08% of the canines had two roots. We found a slightly higher prevalence of the second canal in incisors than in canines (36.62% vs. 20.48%. However, the probability of canines having two separate apical foramina was higher than that for incisors (12.08% vs. 0.64%. Conclusions: In view of the high prevalence of two-canaled mandibular anterior teeth found in this study, it would be prudent to assume that any mandibular anterior tooth being treated is two-canaled until a thorough search proves otherwise.
Root and Canal Morphology of Mandibular Third Molars in an Iranian Population

OpenAIRE

Maryam Kuzekanani; Jahangir Haghani; Hossein Nosrati

2012-01-01

Background and aims A through knowledge of the root canal morphology is required for successful endodontic ther-apy. The aim of this study was to investigate the root and canal morphology of mandibular third molars in Kerman, a prov-ince in southeast of Iran. Materials and methods One-hundred-fifty extracted mandibular third molars were collected randomly from different dental clinics in Kerman. The root canal anatomy and morphology of each tooth was carefully studied using a clearing tech-ni...
Revisión de la distribución de Hyalella Smith, 1874 (Crustacea, Amphipoda) en la Patagonia e islas adyacentes

OpenAIRE

De los Ríos-Escalante,Patricio; Mansilla,Andrés; Anderson,Christopher B

2012-01-01

Se realiza una revisión de las especies de anfípodos del género Hyalella en aguas continentales de la Patagonia, isla Tierra del Fuego, Reserva de la Biosfera de Cabo de Hornos e islas adyacentes (38-54°S). Esta zona austral presenta numerosos tipos de ambientes acuáticos continentales como lagos, humedales y arroyos, y las principales especies en ambientes bentónicos corresponden a anfípodos del género Hyalella. La bibliografía menciona la presencia de H. costera, H. chiloensis, H. falklande...
Effectiveness of different irrigation systems on filling of simulated lateral canals

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sehnaz Yilmaz

2016-09-01

Conclusions: Sonically or ultrasonically irrigation showed significant differences on the filling of the simulated lateral canals at the middle third of the root canals. Ultrasonic activation of the irrigants represented better results in radiographic and cleared specimen evaluation. [Cukurova Med J 2016; 41(3.000: 515-520
A study on FlexMaster : a Ni-Ti rotary engine driven system for root canal preparation.

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Alam, M S; Bashar, A K; Begumr, J A; Kinoshita, J I

2006-07-01

In the present study, the effectiveness of recently introduced rotary Nickel Titanium FlexMaster engine driven system was evaluated for cleaning and shaping of root canals in extracted human teeth and compared with that done by the Nickel Titanium Flexofile hand instruments. A total of 40 root canals from 36 extracted mandibular and maxillary teeth with curvature ranging between 20 and 30 degree were divided into two groups, consisting 20 canals in each. FlexMaster instrumentation was done in 20 canals, using crown-down technique and manual filing with Flexofile was done in other 20 canals, using conventional and step-back techniques. 5.25% sodium hypochlorite (NaOCl) solution and 17% ethelene di-amine tetra-acetic acid (EDTA) were used alternatively for irrigation after canal preparation by each instrument size. Time needed for canal preparation of individual canal was recorded. A procedural error such as instrument breakage was also noted. After preparation, all the roots were cut longitudinally by using diamond burs in turbine handpiece and examined under scanning electron microscope. Apical region was quantified for debris and smear layer based on a 5-score numerical evaluation scale. The data established for scoring the debris and smear layer and preparation time of individual canal were analyzed statistically using the Mann-Whitney U test. Completely cleaned root canals were not found with any of the two instruments and none of the instruments maintained the original canal uniformity and regular dentine surface. Because significantly less debris was found in the apical region using the manual filing technique (p< 0.05). Thus the flexmaster system was found to produce less cleaner root canal walls than manual technique. Only one FlexMaster finishing file sized 30 was separated in the apical region during preparation of 30 degree curved canal. The time taken by FlexMaster was significantly better (p< 0.01) than that of hand instruments.
The Suez Canal as a habitat and pathway for marine algae and seagrasses

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Aleem, A. A.

The Suez Canal supports a diversified benthic algal flora; 133 species of benthic algae are now known from the Canal, as compared with only 24 in 1924. The vertical and horizontal distribution of algae is considered in relation to hydrographic factors. The algae display zonation and 3-4 algal belts are distinguished on the Canal banks on buoys and pier supports. Associated fauna include Balanus amphitrite and Brachidontes variabilis, together with various hydroids, sponges, ascidians, asteroids, ophiuroids and crustaceans. Merceriella enigmatica thrives well in brackish water habitats. The algal flora in the Bitter Lakes resembles that in the Red Sea. The number of Red Sea species decreases from Suez to Port Said in the littoral zone. On the other hand, bottom algae predominantly belong to Red Sea flora. Thirty of the species of algae found belong to the Indo-Pacific flora; half of these are new records to the Canal. Several of these Indo-Pacific algae have recently become established in the Eastern Mediterranean, whereas only two of the Mediterranean macro-algal flora (viz. Caulerpa prolifera and Halopteris scoparia) have been found in the Gulf of Suez. Two seagrasses, Halopia ovalis and Thalassia hemprichii, are recorded for the first time in the Canal. Only Halophila stipulacea has found its way into the Mediterranean via the Suez Canal, but none of the Mediterranean seagrasses is found either in the Canal or in the Red Sea.
Is the prominent ericoid mycorrhizal fungus Rhizoscyphus ericae absent in the Southern Hemisphere’s Ericaceae? A case study on the diversity of root mycobionts in Gaultheria spp. from northwest Patagonia, Argentina

Czech Academy of Sciences Publication Activity Database

Brusone, M. C.; Fontenla, S. B.; Vohník, Martin

2015-01-01

Roč. 25, č. 1 (2015), s. 25-40 ISSN 0940-6360 R&D Projects: GA MŠk 7AMB12AR014 Institutional support: RVO:67985939 Keywords : ericoid mycorrhiza * Gaultheria * Patagonia Subject RIV: EF - Botanics Impact factor: 3.252, year: 2015
Trifid nasopalatine canal: case report of a rare anatomical variation and its surgical implications

International Nuclear Information System (INIS)

Guanaes Gomes Torres, Marianna; Crusoé-Rebello, Margarida Iêda; Faro Valverde, Ludmila de; Torres Andion Vidal, Manuela

2016-01-01

The nasopalatine canal is a long slender structure present in the midline of the anterior maxilla that connects the palate to the floor of the nasal cavity. The nasopalatine canal contains the nasopalatine nerve, the terminal branch of the nasopalatine artery, fibrous connective tissue, adipose tissue, and minor salivary glands. The purpose of this article was to report a case of a trifid nasopalatine canal detected by cone beam computed tomography prior to dental implant placement. A 47-year-old female patient was submitted to cone beam computed tomography. Axial and sagittal sections revealed a trifurcation of the nasopalatine canal. Each canal was separated from the other by bony septa and extended independently from the floor of the nasal cavity to the incisive foramen in the remnant of the alveolar process in the anterior region of the maxilla. Cone beam computed tomography has permitted better visualization of the details and anatomical variations of the nasopalatine canal. Detailed knowledge of variations in the shape, number and size of the nasopalatine canal is fundamental for surgical procedures, such as local anesthesia in the anterior maxillary region and placement of dental implants, in order to prevent damage to important arteries and nerves. (author)
[CT study on the development of facial nerve canal in children].

Science.gov (United States)

Li, J M; Xu, W B; Zhong, J W; Wu, H Y; Dai, W C

2016-10-07

Objective: To assess the characteristics of facial nerve canal between normal anatomy and dysplasia of children in different ages. Methods: A total of 492 health ears were divided into six groups, neonatal group (toddler group(1-3 y, n =102), preschool group (3-6 y, n =100), school group(6-10 y, n =60)and adolescent group (10-14 y, n =82). The length and diameter of facial nerve canal and that angles of first and second genu were measured with CT in each group. Results: ①The lengths of facial nerve canal in neonatal and infancy group were shorter than other four groups, especially in the mastoid segments of facial nerve canal. The lengths of mastoid segments in neonatal, infancy, toddler, preschool, school and adolescent groups were 5.03±0.84, 6.25±1.40, 8.34±1.38, 9.70±1.34, 10.84±1.41 and 12.17±1.83 mm, with P developed completely ( P >0.05). ② The diameter of labyrinth and tympanic segment in neonatal group were narrower than other five groups ( P 0.05). ③The dysplasia of facial nerve canal were occurred on 978 locations. Among them, the percentage of dehiscence, aberrance, partially expanding and bifurcation were 72.9%(713/978), 5.1%(50/978), 18.9%(185/978) and 3.1%(30/978) respectively. The percentage of dehiscence in geniculate fossa segment was decreased significantly with age (neonatal group 85.7%(36/42), infancy group 59.4%(63/106), toddler group 39.2%(40/102), preschool group 33%(33/100), school group 30%(18/60)and adolescent group 26.8%(22/82), with P O.05). Conclusions: The growth of length and dehiscence in labyrinth segment of facial nerve canal are significant in difference ages. The changes of diameter and angles of first and second genu in facial nerve canal, and the rate of other dysplasia are individual.
Detailed abundance analysis of globular clusters in the Local Group. NGC 147, NGC 6822, and Messier 33

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Larsen, S. S.; Brodie, J. P.; Wasserman, A.; Strader, J.

2018-06-01

Context. Globular clusters (GCs) are emerging as powerful tracers of the chemical composition of extragalactic stellar populations. Aims: We present new abundance measurements for 11 GCs in the Local Group galaxies NGC 147, NGC 6822, and Messier 33. These are combined with previously published observations of four GCs in the Fornax and Wolf-Lundmark-Melotte (WLM) galaxies. Methods: The abundances were determined from analyses of integrated-light spectra obtained with the HIRES spectrograph on the Keck I telescope and with UVES on the Very Large Telescope (VLT). We used our analysis technique that was developed for this purpose and tested on Milky Way GCs. Results: We find that the clusters with [Fe/H] -1.5, the GCs in M33 are also α-enhanced, while the GCs that belong to dwarfs (NGC 6822 SC7 and Fornax 4) have closer to solar-scaled α-element abundances. The abundance patterns in SC7 are remarkably similar to those in the Galactic GC Ruprecht 106, including significantly subsolar [Na/Fe] and [Ni/Fe] ratios. In NGC 147, the GCs with [Fe/H] account for about 6% of the total luminosity of stars in the same metallicity range, a lower fraction than those previously found in the Fornax and WLM galaxies, but substantially higher than in the Milky Way halo. Conclusions: At low metallicities, the abundance patterns suggest that GCs in the Milky Way, dwarf galaxies, and M33 experienced similar enrichment histories and/or processes. At higher metallicities, the lower levels of α-enhancement in the GCs found in dwarf galaxies resemble the abundance patterns observed in field stars in nearby dwarfs. Constraining the presence of multiple populations in these GCs is complicated by lack of information about detailed abundances in field stars of the corresponding metallicities. We suggest that correlations such as [Na/Fe] versus [Ni/Fe] may prove useful for this purpose if an accuracy of 0.1 dex or better can be reached for integrated-light measurements. Tables A.1-A.15
Identification of possible factors impacting dental students' ability to locate MB2 canals in maxillary molars.

Science.gov (United States)

Park, Ellen; Chehroudi, Babak; Coil, Jeffrey M

2014-05-01

This study examined the effect of the access size and straight-line path of access on third-year dental students' ability to locate a second mesiobuccal (MB2) canal in maxillary first and second molars. One hundred and six third-year dental students at one Faculty of Dentistry performed simulated root canal treatment with the aid of 2x magnification loupes on extracted teeth. A postgraduate endodontic student subsequently made a reasonable search for an untreated MB2 canal with the aid of a dental operating microscope. The mesiobuccal roots were then sectioned horizontally for determination of the canal configuration. The dental students were able to treat an MB2 canal in 15.8 percent of the teeth, but this was not associated with satisfactory access criteria. The postgraduate endodontic student identified an MB2 canal in 54.7 percent of the remaining tooth samples excluding those where the MB2 canal was found by the dental students; this represented 94.3 percent of those teeth confirmed by horizontal sectioning of the root to have an MB2 canal. The postgraduate student troughed, on average, 2.6 mm before negotiating the MB2 canal. As satisfactory access criteria and straight-line path of access did not correlate with the dental students' ability to find a second mesiobuccal canal, this result has important implications for educational goals with respect to endodontic treatment of maxillary molar teeth.
In-depth morphological study of mesiobuccal root canal systems in maxillary first molars: review

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Seok-Woo Chang

2013-02-01

Full Text Available A common failure in endodontic treatment of the permanent maxillary first molars is likely to be caused by an inability to locate, clean, and obturate the second mesiobuccal (MB canals. Because of the importance of knowledge on these additional canals, there have been numerous studies which investigated the maxillary first molar MB root canal morphology using in vivo and laboratory methods. In this article, the protocols, advantages and disadvantages of various methodologies for in-depth study of maxillary first molar MB root canal morphology were discussed. Furthermore, newly identified configuration types for the establishment of new classification system were suggested based on two image reformatting techniques of micro-computed tomography, which can be useful as a further 'Gold Standard' method for in-depth morphological study of complex root canal systems.
An in vitro evaluation of the degree of pulp tissue dissolution through different root canal irrigation protocols.

Science.gov (United States)

Amato, Massimo; Pantaleo, Giuseppe; Abtellatif, Dina; Blasi, Andrea; Gagliani, Massimo; Iandolo, Alfredo

2018-01-01

The aim of this study is to evaluate in vitro , using artificial lateral canals, the rate of dissolution of the pulp tissue through different protocols of canal irrigation. One hundred artificial canals provided with lateral canals have been used. Each lateral canal was filled with pulp tissue and calibrated to 0.002 mg. All canals were irrigated using five different protocols. Five groups have been used for the experiment: Group A, distilled water (control); Group B, preheated NaOCl; Group C, NaOCl heated inside the canal; Group D, NaOCl ultrasonically activated; and Group E, NaOCl heated inside the canal with ultrasonic activation. All samples were weighed through professional microbalance in three different phases: before insertion of the pulp tissue into the lateral canal, after insertion of the pulp tissue and, finally, after different protocols of irrigation. A statistical analysis with Kruskal-Wallis test and Mann-Whitney test was performed. The partial dissolution of the pulp tissue inside the artificial lateral canal occurs only using the protocol with NaOCl heated inside the canal with ultrasonic activation. Other irrigation protocols are not able to dissolve the pulp tissue. The main objective of endodontic therapy is the removal of damaged tissues and bacteria. Modern literature highlights that it is impossible to remove all the pulp tissues and bacteria from the whole endodontic space. Hence, to achieve excellence and get positive results in the short and long term, it is necessary to use techniques and technologies that may increase the degree of root canal detersion.
Condiciones productivas y exigencias de calidad en la fruticultura de la Patagonia argentina

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Belén Alvaro

2013-01-01

Full Text Available La producción alimentaria está regida, a partir de los años noventa, por requerimientos de calidad e inocuidad que modifican sustancialmente las condiciones productivas del eslabón primario, en el marco de una reestructuración del sistema agroalimentario mundial. El caso en estudio aborda la conformación social de la cadena frutícola localizada en el norte de la Patagonia argentina, donde estos requerimientos se formalizan, entre otros, en las buenas prácticas agrícolas, abordadas como dispositivos de control que interpelan y vuelven complejas las condiciones de reproducción social de los chacareros, como productores independientes en la cadena, con impactos en sus trayectorias vitales y productivas. Se consultaron fuentes secundarias, y se realizó el relevamiento primario de casos. Las conclusiones se inscriben en las tensiones entre configuraciones productivas locales y avances de los controles del capital concentrado.

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