WorldWideScience

Sample records for canals and waterways

  1. Microbial content of Yarmuk River and King Abdulla Canal waterways in Jordan.

    Science.gov (United States)

    Khalil, Mahmoud A; Soofi, Ahmed K; Al-Delaimy, Khalaf S

    2011-01-01

    The aim of this study was to monitor the microbiological contamination of the water of Yarmuk River (YR) and King Abdulla Canal (KAC) in Jordan for 6 months (June-November 2000) for their aerobic plate count, total coliforms, fecal coliforms, fecal Streptococci, Staphylococcus aureus, Salmonella, fungi, algae, and protozoa. Water samples were collected monthly for 6 months (June-November 2000) from three generally representable locations of each of YR and KAC. The procedures of Standard Methods for the Examination of Water and Waste Water were, in general, used. The average counts in log colony forming units/ml water were 5.4, 4.9 aerobic plate counts; 3.4, 3.5 total coliforms; 2.0, 1.9 fecal coliforms; 1.7, 1.6 S.aureus; and 1.7, 1.7 fungi (molds and yeasts), respectively. The presumptive tests for Salmonellae were positive in all samples of the two waterways. Average algae and protozoa counts during 4 months (July-October) in 5-l water samples as log/liter were 6.7, 6.9 in Yarmuk River and 3.2, 3.4 in King Abdulla Canal, respectively. The microbial contents of the sediments of the two waterways and temperature, pH, electric conductivity, turbidity, and dissolved oxygen were also recorded. From the public point of view, the microbial water quality of the two waterways is not suitable for drinking before treatment; it is, however, suitable for agricultural restricted irrigation.

  2. Living Waterways.

    Science.gov (United States)

    Hubbard, Guy

    2001-01-01

    Discusses the use of waterways as subjects in works of art. States that teachers can take their students to a river or canal to help them depict waterways. Explains that the four artworks reproduced in the article offer examples for students. Includes artwork by Franklin McMahon, Canaletto, Nancy Lagana, and Vincent van Gogh. (CMK)

  3. Computers and the Waterways' Project.

    Science.gov (United States)

    Spiegel, Richard A.

    Begun in 1979, the Waterways Project, which provides literary arts program experience for at risk students in New York City, is described in this paper. The Waterways Project was started as a service organization for small press publishers and writers. The paper recounts the project's involvement in book fairs, computer programming, a literary…

  4. Safety And Reduce In Pollution Issues For Inland Waterway Transportation

    Directory of Open Access Journals (Sweden)

    Van Huong Dong

    2017-04-01

    Full Text Available According to the Ministry of Transport inland water transport is one of the five modes of transport in our country play a very important role. Inland waterway transport not only plays a major role in transporting large volumes of goods and passengers but also creates millions of jobs contributing to ensuring social security and national defense and security. However there are still many inadequacies in waterway transportation such as unequal waterway traffic The phenomenon of exploitation of river resources as planned or Process technology is not as planned exploitation of sand gravel etc. are common in most rivers and canals in the country. The signaling system is not synchronized between the signal of the inland waterway management unit and the signal of the owner The handling of domestic goods transportation and inland port management is inadequate The force of the means of development is fast uneven but concentrated in some urban areas and industrial parks. Therefore the Ministry of Transport has proposed a scheme to facilitate the development of a synchronized inland waterway infrastructure linking with other modes of transport To improve the capacity of the crew and the inland waterway transport crews. To create favorable conditions for inland waterway transportation business with reasonable transportation costs Improve the quality of water transport services Ensure safety and environmental friendliness Make a distinct advantage over other modes of transport. Specifically will develop promulgate mechanisms The policy is to facilitate the development of inland waterway infrastructure Build and promulgate mechanism The policy of supporting the development of the fleet has a reasonable structure with a fleet of about 30 self-propelled ships accounting for about 70 of the total number of inland waterway vessels To prioritize the development of the container fleet Inland waterway transportation and training retraining of human resources for

  5. 75 FR 32275 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, Harvey...

    Science.gov (United States)

    2010-06-08

    ..., Inner Harbor Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA AGENCY: Coast Guard, DHS...), Harvey Canal, and Algiers Canal during severe hurricane conditions. Vessels will not be permitted to stay... communities within the IHNC, Harvey, and Algiers Canals from potential hazards associated with vessels being...

  6. 2012 NOAA Ortho-rectified Color Mosaic of Seattle, Duwamish Waterway, and Lake Washington Ship Canal, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains ortho-rectified mosaic tiles, created as a product from the NOAA Integrated Ocean and Coastal Mapping (IOCM) initiative. The source imagery...

  7. 75 FR 39632 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, Harvey...

    Science.gov (United States)

    2010-07-12

    ..., Inner Harbor Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA; Correction ACTION: Interim... Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA into the Code of Federal Regulations. That...

  8. Predictive statistical models linking antecedent meteorological conditions and waterway bacterial contamination in urban waterways.

    Science.gov (United States)

    Farnham, David J; Lall, Upmanu

    2015-06-01

    Although the relationships between meteorological conditions and waterway bacterial contamination are being better understood, statistical models capable of fully leveraging these links have not been developed for highly urbanized settings. We present a hierarchical Bayesian regression model for predicting transient fecal indicator bacteria contamination episodes in urban waterways. Canals, creeks, and rivers of the New York City harbor system are used to examine the model. The model configuration facilitates the hierarchical structure of the underlying system with weekly observations nested within sampling sites, which in turn were nested inside of the harbor network. Models are compared using cross-validation and a variety of Bayesian and classical model fit statistics. The uncertainty of predicted enterococci concentration values is reflected by sampling from the posterior predictive distribution. Issuing predictions with the uncertainty reasonably reflected allows a water manager or a monitoring agency to issue warnings that better reflect the underlying risk of exposure. A model using only antecedent meteorological conditions is shown to correctly classify safe and unsafe levels of enterococci with good accuracy. The hierarchical Bayesian regression approach is most valuable where transient fecal indicator bacteria contamination is problematic and drainage network data are scarce. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. 33 CFR 162.65 - All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary to the Gulf of Mexico east and south of... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.65...

  10. 33 CFR 117.451 - Gulf Intracoastal Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Gulf Intracoastal Waterway. 117... Waterway. (a) The draw of the Lapalco Boulevard Bridge, Harvey Canal Route, mile 2.8 at Harvey, shall open... 319 (Louisa) bridge across the Gulf Intracoastal Waterway, mile 134.0 west of Harvey Lock, near...

  11. Ten years of experience in combining ecology and navigation on Dutch waterways

    NARCIS (Netherlands)

    Boeters, R.E.A.M.; Havinga, H.; Litjens, G.; Verheij, H.J.

    1997-01-01

    In this paper we will discuss the experience gained in the Netherlands with the multifunctional management of waterways. We will especially go into how the functions of rivers and canals for navigation and nature are combined. For this we will briefly go back to the national paper for Seville 1994,

  12. A Regional Waterway Management System for Balancing Recreational Boating and Resource Protection

    Science.gov (United States)

    Swett, Robert A.; Listowski, Charles; Fry, Douglas; Boutelle, Stephen; Fann, David

    2009-06-01

    Florida’s coasts have been transformed over the past three decades as population growth and unprecedented demand for individual shore access to bays and estuaries led to the creation of residential canal developments. Thousands of miles of channels and basins were dredged as a by-product of this urbanization process. The navigable waterways that resulted are now being stressed by increasing boat traffic and canal-side activities. Recognizing their common goal to preserve the recreational and ecological value of southwest Florida waterways, the Florida Department of Environmental Protection, the four-county West Coast Inland Navigation District, and the University of Florida Sea Grant College Program signed a Memorandum of Agreement. The signatories agreed to develop a science-based Regional Waterway Management System (RWMS), which is a new approach to waterway planning and permitting based on carefully mapped channel depths, a census of actual boat populations, and the spatial extent of natural resources. The RWMS provides a comprehensive, regional overview of channel conditions and the geographic distribution and severity of existing impediments to safe navigation and resource protection. RWMS information and analyses result in regional-scale permitting to accommodate water-dependent uses while minimizing environmental impacts and reducing public expenditures. Compared with traditional approaches to waterway management, the science-based RWMS is relatively unbiased, objective, transparent, ecologically sound, and fiscally prudent.

  13. Model-Based Design and Formal Verification Processes for Automated Waterway System Operations

    Directory of Open Access Journals (Sweden)

    Leonard Petnga

    2016-06-01

    Full Text Available Waterway and canal systems are particularly cost effective in the transport of bulk and containerized goods to support global trade. Yet, despite these benefits, they are among the most under-appreciated forms of transportation engineering systems. Looking ahead, the long-term view is not rosy. Failures, delays, incidents and accidents in aging waterway systems are doing little to attract the technical and economic assistance required for modernization and sustainability. In a step toward overcoming these challenges, this paper argues that programs for waterway and canal modernization and sustainability can benefit significantly from system thinking, supported by systems engineering techniques. We propose a multi-level multi-stage methodology for the model-based design, simulation and formal verification of automated waterway system operations. At the front-end of development, semi-formal modeling techniques are employed for the representation of project goals and scenarios, requirements and high-level models of behavior and structure. To assure the accuracy of engineering predictions and the correctness of operations, formal modeling techniques are used for the performance assessment and the formal verification of the correctness of functionality. The essential features of this methodology are highlighted in a case study examination of ship and lock-system behaviors in a two-stage lock system.

  14. 33 CFR 162.90 - White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false White River, Arkansas Post Canal... White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River, Ark... apply to: (1) Waterways. White River between Mississippi River and Arkansas Post Canal, Ark.; Arkansas...

  15. Modelling sailing time and cost for inland waterway transport

    NARCIS (Netherlands)

    Hekkenberg, R.G.; van Dorsser, J.C.M.; Schweighofer, Juha

    2017-01-01

    Transport time and cost are decisive factors for shippers when they choose a mode for their transport. For inland waterway transport in particular, these aspects are more uncertain and less easy to generalize than for road and rail. This is due to the highly variable waterway conditions on

  16. Cyanobacteria of the 2016 Lake Okeechobee and Okeechobee Waterway harmful algal bloom

    Science.gov (United States)

    Rosen, Barry H.; Davis, Timothy W.; Gobler, Christopher J.; Kramer, Benjamin J.; Loftin, Keith A.

    2017-05-31

    The Lake Okeechobee and the Okeechobee Waterway (Lake Okeechobee, the St. Lucie Canal and River, and the Caloosahatchee River) experienced an extensive harmful algal bloom within Lake Okeechobee, the St. Lucie Canal and River and the Caloosahatchee River in 2016. In addition to the very visible bloom of the cyanobacterium Microcystis aeruginosa, several other cyanobacteria were present. These other species were less conspicuous; however, they have the potential to produce a variety of cyanotoxins, including anatoxins, cylindrospermopsins, and saxitoxins, in addition to the microcystins commonly associated with Microcystis. Some of these species were found before, during, and 2 weeks after the large Microcystis bloom and could provide a better understanding of bloom dynamics and succession. This report provides photographic documentation and taxonomic assessment of the cyanobacteria present from Lake Okeechobee and the Caloosahatchee River and St. Lucie Canal, with samples collected June 1st from the Caloosahatchee River and Lake Okeechobee and in July from the St. Lucie Canal. The majority of the images were of live organisms, allowing their natural complement of pigmentation to be captured. The report provides a digital image-based taxonomic record of the Lake Okeechobee and the Okeechobee Waterway microscopic flora. It is anticipated that these images will facilitate current and future studies on this system, such as understanding the timing of cyanobacteria blooms and their potential toxin production.

  17. Global Map: 1:1,000,000-Scale Canals and Aqueducts of the United States - Direct Download

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes Global Map data showing the canals, aqueducts, and the Intracoastal Waterway in the United States, Puerto Rico, and the U.S. Virgin Islands....

  18. Save Our Streams and Waterways.

    Science.gov (United States)

    Indiana State Dept. of Education, Indianapolis. Center for School Improvement and Performance.

    Protection of existing water supplies is critical to ensuring good health for people and animals alike. This program is aligned with the Izaak Walton League of American's Save Our Streams program which is based on the concept that students can greatly improve the quality of a nearby stream, pond, or river by regular visits and monitoring. The…

  19. Andean waterways

    DEFF Research Database (Denmark)

    Rasmussen, Mattias Borg

    Andean Waterways explores the politics of natural resource use in the Peruvian Andes in the context of climate change and neoliberal expansion. It does so through careful ethnographic analysis of the constitution of waterways, illustrating how water becomes entangled in a variety of political, so...

  20. Hydrology of and Current Monitoring Issues for the Chicago Area Waterway System, Northeastern Illinois

    Science.gov (United States)

    Duncker, James J.; Johnson, Kevin K.

    2015-10-28

    The Chicago Area Waterway System (CAWS) consists of a combination of natural and manmade channels that form an interconnected navigable waterway of approximately 90-plus miles in the metropolitan Chicago area of northeastern Illinois. The CAWS serves the area as the primary drainage feature, a waterway transportation corridor, and recreational waterbody. The CAWS was constructed by the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC). Completion of the Chicago Sanitary and Ship Canal (initial portion of the CAWS) in 1900 breached a low drainage divide and resulted in a diversion of water from the Lake Michigan Basin. A U.S. Supreme Court decree (Consent Decree 388 U.S. 426 [1967] Modified 449 U.S. 48 [1980]) limits the annual diversion from Lake Michigan. While the State of Illinois is responsible for the diversion, the MWRDGC regulates and maintains water level and water quality within the CAWS by using several waterway control structures. The operation and control of water levels in the CAWS results in a very complex hydraulic setting characterized by highly unsteady flows. The complexity leads to unique gaging requirements and monitoring issues. This report provides a general discussion of the complex hydraulic setting within the CAWS and quantifies this information with examples of data collected at a range of flow conditions from U.S. Geological Survey streamflow gaging stations and other locations within the CAWS. Monitoring to address longstanding issues of waterway operation, as well as current (2014) emerging issues such as wastewater disinfection and the threat from aquatic invasive species, is included in the discussion.

  1. 33 CFR 207.590 - Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Black Rock Canal and Lock at... Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation. (a) The term “canal” when used in this section will mean all of the Black Rock Waterway, including Black Rock Lock, and all...

  2. Andean waterways

    DEFF Research Database (Denmark)

    Rasmussen, Mattias Borg

    Andean Waterways explores the politics of natural resource use in the Peruvian Andes in the context of climate change and neoliberal expansion. It does so through careful ethnographic analysis of the constitution of waterways, illustrating how water becomes entangled in a variety of political......, social, and cultural concerns. Set in the highland town of Recuay in Ancash, the book traces the ways in which water affects political and ecological relations as glaciers recede. By looking at the shared waterways of four villages located in the foothills of Cordillera Blanca, it addresses pertinent...

  3. 33 CFR 117.799 - Long Island, New York Inland Waterway from East Rockaway Inlet to Shinnecock Canal.

    Science.gov (United States)

    2010-07-01

    ... need not be opened for sailing vessels, unless the vessels are under machinery power or under tow, if... bridge, mile 1.1 across Quoque Canal and the Smith Point bridge, mile 6.1 across Narrow Bay shall open on... vessel traffic, provided at least a two-hour advance notice is given by calling the number posted at the...

  4. USGS Small-scale Dataset - Global Map: 1:1,000,000-Scale Canals and Aqueducts of the United States 201406 FileGDB 10.1

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes Global Map data showing the canals, aqueducts, and the Intracoastal Waterway in the United States, Puerto Rico, and the U.S. Virgin Islands....

  5. USGS Small-scale Dataset - Global Map: 1:1,000,000-Scale Canals and Aqueducts of the United States 201406 Shapefile

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This map layer includes Global Map data showing the canals, aqueducts, and the Intracoastal Waterway in the United States, Puerto Rico, and the U.S. Virgin Islands....

  6. 33 CFR 109.07 - Anchorages under Ports and Waterways Safety Act.

    Science.gov (United States)

    2010-07-01

    ... Waterways Safety Act. 109.07 Section 109.07 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES GENERAL § 109.07 Anchorages under Ports and Waterways Safety Act. The provisions of section 4 (a) and (b) of the Ports and Waterways Safety Act as delegated to the Commandant of...

  7. 33 CFR 110.1a - Anchorages under Ports and Waterways Safety Act.

    Science.gov (United States)

    2010-07-01

    ... Waterways Safety Act. 110.1a Section 110.1a Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS § 110.1a Anchorages under Ports and Waterways Safety Act. (a) The anchorages listed in this section are regulated under the Ports and Waterways Safety Act (33...

  8. Do We Need to Rethink Our Waterways? Values of Ageing Waterways in Current and Future Society

    NARCIS (Netherlands)

    Hijdra, Arjan; Arts, Jos; Woltjer, Johan

    In the past canals were developed, and some rivers were heavily altered, driven by the need for good transportation infrastructure. Major investments were made in navigation locks, weirs and artificial embankments, and many of these assets are now reaching the end of their technical lifetime. Since

  9. 78 FR 34293 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, New Orleans...

    Science.gov (United States)

    2013-06-07

    ... be subject to differing interpretations over time, and expressing a desire for long-term consistency... ensure consistent enforcement and application over the long-term. During the period of enforcement... exist for departure from the area before the RNA goes into effect. If you think that your business...

  10. 33 CFR 117.795 - Jamaica Bay and Connecting Waterways.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Jamaica Bay and Connecting Waterways. 117.795 Section 117.795 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.795 Jamaica Bay and...

  11. 33 CFR 207.160 - All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary...

    Science.gov (United States)

    2010-07-01

    ...) Locks. All Government owned or operated locks and hurricane gate chambers and appurtenant structures in... District Engineers. The use, administration, and navigation of these waterways, Federal locks and hurricane... least six inches less than the depth on miter sills or breast walls, or which have projections or sharp...

  12. Andean waterways

    DEFF Research Database (Denmark)

    Rasmussen, Mattias Borg

    , social, and cultural concerns. Set in the highland town of Recuay in Ancash, the book traces the ways in which water affects political and ecological relations as glaciers recede. By looking at the shared waterways of four villages located in the foothills of Cordillera Blanca, it addresses pertinent...

  13. Water quality condition and trend in North Queensland waterways.

    Science.gov (United States)

    Cox, M E; Moss, A; Smyth, G K

    2005-01-01

    The Queensland Environmental Protection Agency monitored water quality at 133 sites in North Queensland waterways between Cooktown and Bundaburg from 1992 to 2001. Condition of the waterways was rated by comparing recent data with the Queensland Water Quality Guidelines. Long-term trends were analysed using a censored regression technique that incorporates the effects of flow, temperature, seasonality and allows for long-term non-linear trends. Many sites were in good condition; those in poor condition were usually impacted by point source discharges; those in moderate condition were usually impacted by agricultural land use. There were no consistent long-term trends across the whole region. Recommendations for future programs include incorporating pressure indicators, ensuring high standards of quality assurance, including covariates such as rainfall in trend assessment and continuing programs over more than 10 years to allow detection of trends due to changes in land-use.

  14. Port and Waterways Safety Assessment Workshop Report: San Francisco

    Science.gov (United States)

    2008-08-01

    North and South Bays • Delta – powerboat races at Rio Vista, Mandeville Island, Discovery Bay • Crab season – vessels take up the entire waterway...channels • Rio Vista Bridge – one-way traffic; 250 feet wide • Old Sacramento River – very narrow, but some tug and barge traffic to repair levees...are a few intermediate vessels in Vallejo and Alameda that can provide smaller-lift operations if needed) Trends: • None identified Existing

  15. Transitioning to a waterways city: municipal context, capacity and commitment.

    Science.gov (United States)

    Morison, P J; Brown, R R; Cocklin, C

    2010-01-01

    In Melbourne, Australia, the adoption of Water Sensitive Urban Design (WSUD) and the inclusion of best practice in new urban development has shifted the "drained city" of the 1960s toward an environmentally-oriented "waterways city" for the future. However, the "waterways city" is tenuous owing to the variable commitment of local municipalities to WSUD. This paper reports on the first phase of a social research project, which aims to secure a model of the waterways city by addressing the commitment and capacity deficits of local municipalities. Municipal commitment and capacity across three geographical areas in Melbourne are measured quantitatively using an innovative, comprehensive, and replicable assessment technique. The results show variability in municipal capacity and commitment across the areas, with a pronounced deficit in the rural-regional area. Consequently, intergovernmental attempts to normalise modes of integrated urban water management (such as WSUD) need to include innovative and flexible mechanisms that are responsive to the dynamics of municipal commitment and capacity. These principles have broader application to cities internationally where the management of urban stormwater is the shared responsibility of multiple governments.

  16. Nature and the river: a natural resources report of the Chicago and Calumet waterways.

    Science.gov (United States)

    Barbara J Moore; John D. Rogner; Drew Ullberg

    1998-01-01

    In 1992, the National Park Service initiated a project to galvanize local interest in the conservation and use of the Chicago Waterway System. The purpose of this project was to promote local stewardship of the waterway system through the integration of economic development, recreation, and environmental conservation. As a result, the ChicagoRivers Demonstration...

  17. Economising mooring and guiding constructions at lock approaches in inland waterways – the Dutch experience

    NARCIS (Netherlands)

    Koedijk, O.C.

    2015-01-01

    As a result of diminishing budgets for maintenance, the Dutch waterway authority Rijkswaterstaat is amongst others in search for economizing infrastructural facilities for commercial inland vessels along its waterways. One type of those facilities are the mooring constructions for line up- and

  18. State Lands by Administrator - Trails and Waterways

    Data.gov (United States)

    Minnesota Department of Natural Resources — DNR land ownership and administrative interest mapped to the PLS forty level. This layer merges the DNR Control Point Generated PLS layer with IBM mainframe-based...

  19. Feasability study for waterway infrastructure: International overview and methodological recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Santos Fontes Pereira, L. dos; Brandão, R.; Yamashita, Y.; Guilherme de Aragão, J.J.

    2016-07-01

    The context in which the waterway transportation is in Brazil makes clear the development need of specific methodologies for the sector planning. This paper aims to compare the methods of analysis of technical, economic and environmental viability, adopted in Europe, United States and Brazil, listing the best practices and possible improvements of the method adopted in Brazil. The analysis of the documents was based on comparative method, seeking the common elements from its attributes. Each document was analysed in terms of: its structure; type of impacts; required indicators on each impact analysis; reference values for classification of indicators; and the form of integrated analysis of different impacts. The study suggests the inclusion of certain changes in the methodology of calculation and in its combination of tools and parameters used in the measurement of fiscal impacts on the comparative analysis of standard models usually adopted in the United States, Europe and the World Bank. (Author)

  20. 78 FR 14185 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA

    Science.gov (United States)

    2013-03-05

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA AGENCY... drawbridge across the Harvey Canal Route, Gulf Intracoastal Waterway (GIWW), mile 2.8 at New Orleans... Waterway, mile 2.8 at New Orleans, Jefferson Parish, Louisiana. The bridge has a vertical clearance of 45...

  1. 76 FR 70345 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA

    Science.gov (United States)

    2011-11-14

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA AGENCY... Waterway (GIWW), mile 2.8 at Harvey, Jefferson Parish, Louisiana. The deviation is necessary to allow for... Span Bridge across the Harvey Canal Route, Intracoastal Waterway, mile 2.8 at Harvey, Jefferson Parish...

  2. Developmental spinal canal stenosis and somatotype.

    OpenAIRE

    Nightingale, S.

    1989-01-01

    The hypothesis that somatotype and cervical spine developmental canal stenosis may be associated has been investigated by anthropometry and measurement of lateral projection cervical spine radiographs. A significant association of canal size with somatotype has been found such that those with developmentally narrow canals are more likely to have relatively shorter long-bones, particularly in the upper arm, and longer trunks.

  3. Effect of climate change on crop production patterns with implications to transport flows and inland waterways.

    Science.gov (United States)

    2011-12-01

    This project analyzed the demand for transportation capacity and changes in transportation flows on : inland waterways due to shifts in crop production patterns induced by climate change. Shifts in the crop : production mix have been observed in rece...

  4. Health characteristics of inland waterway merchant marine captains and pilots.

    Science.gov (United States)

    Scovill, S M; Roberts, T K; McCarty, D J

    2012-12-01

    Most published studies on seafarer health have focused on patterns of mortality, injury and communicable diseases. Little information is available regarding lifestyle-related cardio-metabolic disease in maritime populations. To describe health characteristics of a population of US inland waterway merchant marine captains and pilots. A cross-sectional study of the health characteristics of mariners required to complete the United States Coast Guard physical assessment at a regional medical centre from 2003-10. Variables collected included self-reported smoking status, body mass index, fasting lipids, glucose and triglyceride levels, blood pressure and treadmill time and maximal oxygen uptake as measured using the Bruce Protocol. Major medical conditions related to lifestyle and risk for metabolic syndrome were also assessed. There were 388 participants. The study population had high prevalence of obesity (61%), smoking (41%), high triglycerides (42%), low HDL cholesterol (47%), high blood pressure (42%), high fasting glucose (22%) and three or more features of the metabolic syndrome (39%). This population exhibited a high prevalence of chronic disease risk factors and could potentially benefit from health promotion programmes aimed at improving health and fitness.

  5. Sediment contamination and associates laboratory-measured bioaccumulation in New York/New Jersey waterways

    Energy Technology Data Exchange (ETDEWEB)

    Rosman, L.B. [Army Corps of Engineers, New York, NY (United States); Barrows, E.S. [Battelle/Marine Sciences Lab., Sequim, WA (United States)

    1995-12-31

    Sediments from 10 New York/New Jersey waterways within the Hudson-Raritan Estuary and Long Island Sound were collected to depths representative of dredging activity. Composited core sediments representing each waterway were analyzed for metals, PAHs, PCBs, and pesticides. To assess bioaccumulation, sand worms (Nereis virens) and blunt-nose clams (Macoma nasuta) were exposed for 28 days to sediment composites and to New York Bight sediment. Tissues were analyzed for the same constituents as the sediment samples. The results highlight the range and magnitude of sediment contamination in NY/NJ waterways. Concentrations of some metals in sediments, compared with NY Bight sediment, were at least 10 times higher. Total PAHs reached 30,000 {micro}g/kg (dry weight). The sum of DDT, DDD, and DDE, the dominant pesticides, exceeded 3,000{micro}g/kg (dry weight). Total PCBs approached 3,000 {micro}g/kg (dry weight). Tissues exposed to sediments from several waterways bioaccumulated organic compounds at concentrations 10 times greater than those exposed to New York Bight sediments. Metals were bioaccumulated to a lesser degree. The presence and extent of bioaccumulated contaminants, along with sediment chemistry and benthic toxicity, create a profile characterizing each waterway.

  6. Relationships Between Perceived Coastal Waterway Condition and Social Aspects of Quality of Life

    Directory of Open Access Journals (Sweden)

    Melanie E. Cox

    2006-06-01

    Full Text Available Previous research has shown that the presence of natural areas is beneficial to human well-being. However, to date there have been few published studies of the effects that the condition of natural areas have on well-being. We hypothesize that coastal waterways that are perceived to be in better condition are visited more often by local residents, and as a result, residents will develop a stronger sense of place and stronger social relations with other residents, which will in turn lead to a higher quality of life. A survey was conducted to test this hypothesis in two coastal regions in Queensland, Australia. A weak relationship was found between perceived coastal quality and the number of recreational visits. In both study areas, frequency of visits to coastal waterways was significantly related to quality of life through an increased sense of place and social contacts. In the Douglas region, sense of place and social capital were closely related, and social capital was also related to quality of life. In both study areas, residents were most likely to visit waterways that were located in close proximity to their residence, suggesting that management of all waterways is essential for human well-being, and that benefits to humans will result from rehabilitating degraded waterways.

  7. Developmental spinal canal stenosis and somatotype.

    Science.gov (United States)

    Nightingale, S

    1989-01-01

    The hypothesis that somatotype and cervical spine developmental canal stenosis may be associated has been investigated by anthropometry and measurement of lateral projection cervical spine radiographs. A significant association of canal size with somatotype has been found such that those with developmentally narrow canals are more likely to have relatively shorter long-bones, particularly in the upper arm, and longer trunks. Images PMID:2769282

  8. Complete Lesson 6: Keeping All of Our Waterways Clean

    Science.gov (United States)

    Looking outside, this lesson explores waterways (streams, rainwater runoff, drainage pollution) with a focus on urban waterways. Students learn about the water cycle and how to keep pollution out of waterways. Mercury in fish is also addressed.

  9. Developing a public information and engagement portal of urban waterways with real-time monitoring and modeling.

    Science.gov (United States)

    Cochrane, T A; Wicke, D; O'Sullivan, A

    2011-01-01

    Waterways can contribute to the beauty and livelihood of urban areas, but maintaining their hydro-ecosystem health is challenging because they are often recipients of contaminated water from stormwater runoff and other discharges. Public awareness of local waterways' health and community impacts to these waterways is usually poor due to of lack of easily available information. To improve community awareness of water quality in urban waterways in New Zealand, a web portal was developed featuring a real-time waterways monitoring system, a public forum, historical data, interactive maps, contaminant modelling scenarios, mitigation recommendations, and a prototype contamination alert system. The monitoring system featured in the web portal is unique in the use of wireless mesh network technology, direct integration with online modelling, and a clear target of public engagement. The modelling aims to show the origin of contaminants within the local catchment and to help the community prioritize mitigation efforts to improve water quality in local waterways. The contamination alert system aims to keep managers and community members better informed and to provide a more timely response opportunity to avert any unplanned or accidental contamination of the waterways. Preliminary feedback has been positive and is being supported by local and regional authorities. The system was developed in a cost-effective manner providing a community focussed solution for quantifying and mitigating key contaminants in urban catchments and is applicable and transferable to other cities with similar stormwater challenges.

  10. Genetic and phenotypic diversity of Ralstonia solanacearum biovar 2 strains obtained from Dutch waterways

    NARCIS (Netherlands)

    Stevens, P.; van Elsas, J.D.

    A novel set of Ralstonia solanacearum biovar 2 isolates was obtained, at several sampling occasions, from Dutch waterways, sediment and bittersweet plants and their genetic and phenotypic diversity was investigated. As reference strains, two previously-described strains obtained from diseased potato

  11. 33 CFR 207.187 - Gulf Intracoastal Waterway, Tex.; special floodgate, lock and navigation regulations.

    Science.gov (United States)

    2010-07-01

    ... vessel to determine whether a safe passage can be effected, give due consideration to the vessel's power... Channels 12, 13, 14 and 16. Call letters for the floodgates are WUI 411 and for the locks are WUI 412. (ii... steel tower 85 feet high located on the northeast point of land at the Gulf Intracoastal Waterway...

  12. 78 FR 75359 - Waterway Suitability Assessment for Construction and Operation of Liquefied Gas Terminals; Orange...

    Science.gov (United States)

    2013-12-11

    ... Terminals; Orange, TX AGENCY: Coast Guard, DHS. ACTION: Notice and request for comments. SUMMARY: In... Hazardous Gas (LHG) at its Orange, Texas facility. The Coast Guard is notifying the public of this action to... increase in LNG or LHG marine traffic in the associated waterway. INVISTA, S.a.r.l. located in Orange...

  13. 75 FR 11870 - Inland Waterways Users Board

    Science.gov (United States)

    2010-03-12

    ... Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S.... Name of Committee: Inland Waterways Users Board (Board). Date: April 13, 2010. Location: The Waterford... navigation projects and studies and the status of the Inland Waterways Trust Fund. FOR FURTHER INFORMATION...

  14. 33 CFR 117.317 - Okeechobee Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Okeechobee Waterway. 117.317... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.317 Okeechobee Waterway. (a) Exempt... train approaches the bridge it will stop and a crewmember will observe the waterway for approaching...

  15. 78 FR 72070 - Inland Waterways Users Board

    Science.gov (United States)

    2013-12-02

    ... Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S.... Name of Committee: Inland Waterways Users Board (Board). Date: January 14, 2014. Location: Meeting at... inland navigation projects and studies, the status of the Inland Waterways Trust Fund, funding for Fiscal...

  16. 33 CFR 117.1041 - Duwamish Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Duwamish Waterway. 117.1041... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Washington § 117.1041 Duwamish Waterway. (a) The draws of each bridge across the Duwamish Waterway shall open on signal, except as follows: (1) From Monday...

  17. 75 FR 57264 - Inland Waterways Users Board

    Science.gov (United States)

    2010-09-20

    ... Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S.... Name of Committee: Inland Waterways Users Board (Board). Date: October 20, 2010. Location: The Isle... and the status of the Inland Waterways Trust Fund. FOR FURTHER INFORMATION CONTACT: Mr. Mark R...

  18. 76 FR 11216 - Inland Waterways Users Board

    Science.gov (United States)

    2011-03-01

    ... Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S.... Name of Committee: Inland Waterways Users Board (Board). Date: April 1, 2011. Location: The Westin New... studies and the status of the Inland Waterways Trust Fund, the funding status for Fiscal Year (FY) 2011...

  19. 77 FR 69447 - Inland Waterways Users Board

    Science.gov (United States)

    2012-11-19

    ... Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S.... Name of Committee: Inland Waterways Users Board (Board). Date: December 19, 2012. Location: The Julian... studies and the status of the Inland Waterways Trust Fund, the funding status for Fiscal Year (FY) 2013...

  20. 33 CFR 117.123 - Arkansas Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Arkansas Waterway. 117.123... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.123 Arkansas Waterway. (a) Across the Arkansas Waterway, the draw of the Rob Roy Drawbridge, mile 67.4 at Pine Bluff, Arkansas, is maintained in...

  1. Mandibular Canal Enlargement: Clinical and Radiological Characteristics

    Directory of Open Access Journals (Sweden)

    Chong Jun Ai

    2017-01-01

    Full Text Available Enlargement of the mandibular canal is a rare radiological finding. Clinically, it may or may not be associated with sensory deficits. We report four cases of widening of the mandibular canal observed with various methods of imaging with different clinical characteristics. We describe this unique radiological finding and elaborate the importance of quality assessment of the imaging that is vital for accurate diagnosis and treatment planning. Clinicians should be mindful when assessing the imaging whenever the size of the mandibular canal is implicated. The case ranged from a benign tumor to malignancy, radiological errors, and artifacts. A more superior imaging or treatment modality was necessary to ascertain the diagnosis.

  2. 33 CFR 162.115 - Keweenaw Waterway, Mich.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Keweenaw Waterway, Mich. 162.115 Section 162.115 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.115 Keweenaw Waterway, Mich. No...

  3. Analysis of Salinity Intrusion in the Waccamaw River and Atlantic Intracoastal Waterway near Myrtle Beach, South Carolina, 1995–2002

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This record is a USGS unpublished report about saltwater intrusion in the Waccamaw River and the Intracoastal Waterway. Six reservoirs in North Carolina discharge...

  4. Monitoring of metal pollution in waterways across Bangladesh and ecological and public health implications of pollution.

    Science.gov (United States)

    Kibria, Golam; Hossain, Md Maruf; Mallick, Debbrota; Lau, T C; Wu, Rudolf

    2016-12-01

    Using innovative artificial mussels technology for the first time, this study detected eight heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, U, Zn) on a regular basis in waterways across Bangladesh (Chittagong, Dhaka and Khulna). Three heavy metals, viz. Co, Cr and Hg were always below the instrumental detection levels in all the sites during the study period. Through this study, seven metal pollution "hot spots" have been identified, of which, five "hot spots" (Cu, Fe, Mn, Ni, Pb) were located in the Buriganga River, close to the capital Dhaka. Based on this study, the Buriganga River can be classified as the most polluted waterway in Bangladesh compared to waterways monitored in Khulna and Chittagong. Direct effluents discharged from tanneries, textiles are, most likely, reasons for elevated concentrations of heavy metals in the Buriganga River. In other areas (Khulna), agriculture and fish farming effluents may have caused higher Cu, U and Zn in the Bhairab and Rupsa Rivers, whereas untreated industrial discharge and ship breaking activities can be linked to elevated Cd in the coastal sites (Chittagong). Metal pollution may cause significant impacts on water quality (irrigation, drinking), aquatic biodiversity (lethal and sub-lethal effects), food contamination/food security (bioaccumulation of metals in crops and seafood), human health (diseases) and livelihoods of people associated with wetlands. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Canal and isthmus debridement efficacy using a sonic irrigation technique in a closed-canal system.

    Science.gov (United States)

    Johnson, Meenal; Sidow, Stephanie J; Looney, Stephen W; Lindsey, Kimberly; Niu, Li-na; Tay, Franklin R

    2012-09-01

    This in vitro study compared debridement efficacies of a sonic irrigation technique (Vibringe; Cavex Holland BV, Haarlem, The Netherlands) with side-vented needle irrigation (SNI) in the mesiobuccal root of maxillary first molars. Twenty roots with narrow isthmuses (≤ 1/4 canal diameter) were selected using micro-computed tomography scanning. Collagen solution was injected into canals/isthmuses and reconstituted with NH(4)OH to simulate canal debris. Each root was sealed apically and embedded in polyvinyl siloxane simulating a closed-canal system. Canals were instrumented to size 40/.04 taper 1 mm short of the anatomic apex. The final irrigation was performed with the Vibringe or SNI. Roots were demineralized, sectioned at 6 levels (1.2-3.2 mm) from the anatomic apex, and stained using Masson trichrome stain. The areas occupied by canals and isthmus and the debris-containing areas were statistically analyzed with repeated-measures analyses using "irrigation technique" as the between factor and "canal level" as the within factor (α = 0.05). Canals had significantly more debris at 1.2 and 1.6 mm (P .05). Considerably more debris remained at 1.2 and 2.0 mm for the Vibringe (P < .05). A significant difference was observed between the canal and the isthmus (P < .001). There is no difference between the Vibringe and SNI in their overall debridement efficacy in apical one third of the mesiobuccal root of maxillary first molars. Published by Elsevier Inc.

  6. Amazon dams and waterways: Brazil's Tapajós Basin plans.

    Science.gov (United States)

    Fearnside, Philip M

    2015-09-01

    Brazil plans to build 43 "large" dams (>30 MW) in the Tapajós Basin, ten of which are priorities for completion by 2022. Impacts include flooding indigenous lands and conservation units. The Tapajós River and two tributaries (the Juruena and Teles Pires Rivers) are also the focus of plans for waterways to transport soybeans from Mato Grosso to ports on the Amazon River. Dams would allow barges to pass rapids and waterfalls. The waterway plans require dams in a continuous chain, including the Chacorão Dam that would flood 18,700 ha of the Munduruku Indigenous Land. Protections in Brazil's constitution and legislation and in international conventions are easily neutralized through application of "security suspensions," as has already occurred during licensing of several dams currently under construction in the Tapajós Basin. Few are aware of "security suspensions," resulting in little impetus to change these laws.

  7. Some factors affecting SPME analysis and PAHs in Philadelphia's urban waterways.

    Science.gov (United States)

    Cheng, Xianhao; Forsythe, Jennifer; Peterkin, Earl

    2013-05-01

    Solid phase microextraction (SPME) opened up a new era in separation science and the technique has developed quickly over the past two decades. However, there are still aspects deserving more study. In this study, the effects of salt-addition, SPME fiber thickness and sample vial size on the analysis of PAHs in the aqueous phase were evaluated. An analytical method based on EPA Method 8272 was devised for the analysis of PAHs in environmental water. PAHs were analyzed in selected waterways of the greater Philadelphia area. The results show the feasible application of this method to determine the range, spatial variation of PAH concentration, composition profile and relationship with dissolved organic matter for the Philadelphia watershed. Based on above information, PAH pollution sources were evaluated along with their dynamic backgrounds. Comparison of PAH concentration in the studied area with those of other urban waterways worldwide shows that PAHs in the studied waterways were found, in this study, to be within the low range of reported concentrations and meet the criteria of the World Health Organization (WHO). The results also demonstrate that this method is suitable and reliable in monitoring PAH concentrations in environmental water. Published by Elsevier Ltd.

  8. Using chloride and other ions to trace sewage and road salt in the Illinois Waterway

    Science.gov (United States)

    Kelly, W.R.; Panno, S.V.; Hackley, Keith C.; Hwang, H.-H.; Martinsek, A.T.; Markus, M.

    2010-01-01

    Chloride concentrations in waterways of northern USA are increasing at alarming rates and road salt is commonly assumed to be the cause. However, there are additional sources of Cl- in metropolitan areas, such as treated wastewater (TWW) and water conditioning salts, which may be contributing to Cl- loads entering surface waters. In this study, the potential sources of Cl- and Cl- loads in the Illinois River Basin from the Chicago area to the Illinois River's confluence with the Mississippi River were investigated using halide data in stream samples and published Cl- and river discharge data. The investigation showed that road salt runoff and TWW from the Chicago region dominate Cl- loads in the Illinois Waterway, defined as the navigable sections of the Illinois River and two major tributaries in the Chicago region. Treated wastewater discharges at a relatively constant rate throughout the year and is the primary source of Cl- and other elements such as F- and B. Chloride loads are highest in the winter and early spring as a result of road salt runoff which can increase Cl- concentrations by up to several hundred mg/L. Chloride concentrations decrease downstream in the Illinois Waterway due to dilution, but are always elevated relative to tributaries downriver from Chicago. The TWW component is especially noticeable downstream under low discharge conditions during summer and early autumn when surface drainage is at a minimum and agricultural drain tiles are not flowing. Increases in population, urban and residential areas, and roadways in the Chicago area have caused an increase in the flux of Cl- from both road salt and TWW. Chloride concentrations have been increasing in the Illinois Waterway since around 1960 at a rate of about 1 mg/L/a. The increase is largest in the winter months due to road salt runoff. Shallow groundwater Cl- concentrations are also increasing, potentially producing higher base flow concentrations. Projected increases in population and

  9. The Panama Canal and Social Justice.

    Science.gov (United States)

    Wilde, Margaret D., Ed.

    The booklet, designed to explore the issues of international justice in the context of the Gospel, reviews relations between the United States and Panama. It includes background materials and a study guide for parish leaders and other educators. The central question pertaining to the Panama Canal concerns the rights of the United States according…

  10. Infrared typmanic tempature and ear canal morphology

    NARCIS (Netherlands)

    Daanen, H.A.M.

    2006-01-01

    Several publications indicate that the infrared tympanic temperature (IRTT) underestimates the core temperature of the body when the ear canal is long, curvy and narrow. In order to quantify these observations, a study was performed in 10 subjects. The IRTT was determined and compared to the

  11. Spatial distribution of PAHs and associated laboratory-measured bioaccumulation in New York/New Jersey waterways

    Energy Technology Data Exchange (ETDEWEB)

    Rosman, L.B. [Army Corps of Engineers, New York, NY (United States); Barrows, E.S. [Battelle/Marine Sciences Lab., Sequim, WA (United States)

    1995-12-31

    Sediment core samples from New York/New Jersey waterways within the Hudson-Raritan Estuary and Long Island Sound were collected to depths representative of dredging activity. Sediment was also collected from a reference site in the New York Bight as a comparison. Composited core sediments representing each waterway were analyzed for PAHs, sediment grain size, and total organic carbon. To assess bioaccumulation, sand worms (Nereis virens) and blunt-nose clams (Macoma nasuta) were exposed for 28 days to sediment composites and to New York Bight sediment. Tissues were analyzed for the same constituents as the sediment samples, as well as for lipid content. The results highlight the range and magnitude of PAH concentrations in sediments of NY/NJ waterways. Concentrations of total PAHs ranged from undetected to 30,000 {micro}g/kg (dry weight). Tissues exposed to sediments from several waterways bioaccumulated organic compounds at concentrations as much as 10 times greater than those exposed to New York Bight sediments. The presence and extent of bioaccumulated compounds, along with benthic toxicity data, create a profile characterizing each waterway.

  12. The influence of hydrology and waterway distance on population structure of Chinook salmon Oncorhynchus tshawytscha in a large river.

    Science.gov (United States)

    Olsen, J B; Beacham, T D; Wetklo, M; Seeb, L W; Smith, C T; Flannery, B G; Wenburg, J K

    2010-04-01

    Adult Chinook salmon Oncorhynchus tshawytscha navigate in river systems using olfactory cues that may be influenced by hydrologic factors such as flow and the number, size and spatial distribution of tributaries. Thus, river hydrology may influence both homing success and the level of straying (gene flow), which in turn influences population structure. In this study, two methods of multivariate analysis were used to examine the extent to which four indicators of hydrology and waterway distance explained population structure of O. tshawytscha in the Yukon River. A partial Mantel test showed that the indicators of hydrology were positively associated with broad-scale (Yukon basin) population structure, when controlling for the influence of waterway distance. Multivariate multiple regression showed that waterway distance, supplemented with the number and flow of major drainage basins, explained more variation in broad-scale population structure than any single indicator. At an intermediate spatial scale, indicators of hydrology did not appear to influence population structure after accounting for waterway distance. These results suggest that habitat changes in the Yukon River, which alter hydrology, may influence the basin-wide pattern of population structure in O. tshawytscha. Further research is warranted on the role of hydrology in concert with waterway distance in influencing population structure in Pacific salmon.

  13. Sewage Contamination under Different Storm and Hydrologic Conditions in Three Urban Waterways

    Science.gov (United States)

    Templar, H.; Corsi, S.; McLellan, S. L.

    2014-12-01

    Fecal contamination in urban waterways is a major public and environmental health threat. Sanitary sewer and combined sewer overflows are major point sources of fecal pollution. Additionally, stormwater runoff and failing sewer infrastructure contribute fecal contamination and pathogens to urban waterways. Traditionally, fecal indicator bacteria such as E. coli, enterococci, and fecal coliforms are used to gauge fecal contamination in water; however, these general indicators are unable to distinguish fecal sources in the environment. This study used two human-specific fecal indicator bacteria to identify human sewage contamination in Milwaukee, Wisconsin, where three rivers form an estuary that discharges to Lake Michigan. Two-hour composite samples were collected at four sites, one in each of the three rivers and one in the estuary, to represent the entire hydrograph before, during, and after a rain event. Samples were collected throughout a variety of conditions, including dry-weather baseline, light and heavy rain events, and combined sewage overflows (CSOs). These samples were analyzed using quantitative polymerase chain reaction (qPCR) assays to determine human sewage loads in each river during each type of event. Low levels of human indicators were found during dry-weather baseline conditions, and loads increased significantly (one to two orders of magnitude) during rain events. Sampling upstream of the estuary indicated sewage contamination was originating in the heavily urbanized part of the watersheds, likely a result of failing infrastructure. CSO events contributed the highest loads, which were on average ten-fold higher than rainfall events with no CSO. This information will be a useful for directing the efforts of local agencies and municipalities to investigate failing infrastructure, as well as agencies at the state and federal levels to create appropriate goals to address the human health concerns that are posed by sewage contamination in urban

  14. Water-quality sampling plan for evaluating the distribution of bigheaded carps in the Illinois Waterway

    Science.gov (United States)

    Duncker, James J.; Terrio, Paul J.

    2017-02-27

    The two nonnative invasive bigheaded carp species (bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix) that were accidentally released in the 1970s have spread widely into the rivers and waterways of the Mississippi River Basin. First detected in the lower reaches of the Illinois Waterway (IWW, the combined Illinois River-Des Plaines River-Chicago Area Waterway System) in the 1990s, bighead and silver carps moved quickly upstream, approaching the Chicago Area Waterway System. The potential of substantial negative ecological and economic impact to the Great Lakes from the presence of these species is a concern. However, since 2006, the population front of bigheaded carps has remained in the vicinity of Joliet, Illinois, near river mile 278. This reach of the IWW is characterized by stark changes in habitat, water quality, and food resources as the waterway transitions from a primarily agricultural landscape to a metropolitan and industrial canal system. This report describes a 2015 plan for sampling the IWW to establish water-quality conditions that might be contributing to the apparent stalling of the population front of bigheaded carps in this reach. A detailed description of the study plan, Lagrangian-style sampling approach, selected analytes, sampling methods and protocols are provided. Hydrographs from streamflow-gaging stations show IWW conditions during the 2015 sampling runs.

  15. Impact of grassed waterways and compost filter socks on the quality of surface runoff from corn fields.

    Science.gov (United States)

    Shipitalo, Martin J; Bonta, James V; Dayton, Elizabeth A; Owens, Lloyd B

    2010-01-01

    Surface runoff from cropland frequently has high concentrations of nutrients and herbicides, particularly in the first few events after application. Grassed waterways can control erosion while transmitting this runoff offsite, but are generally ineffective in removing dissolved agrochemicals. In this study, we routed runoff from one tilled (0.67 ha) and one no-till watershed (0.79 ha) planted to corn (Zea mays L.) into parallel, 30-m-long grassed waterways. Two 46-cm-diam. filter socks filled with composted bark and wood chips were placed 7.5 m apart in the upper half of one waterway and in the lower half of the other waterway to determine if they decreased concentrations of sediment and dissolved chemicals. Automated samplers were used to obtain samples above and below the treated segments of the waterways for two crop years. The filter socks had no significant effect (P waterways used with the tilled watershed. The filter socks significantly increased the concentrations of Cl, NO(3)-N, PO(4)-P, SO(4), Ca, K, Na, and Mg in runoff from at least one watershed, probably due to soluble forms of these ions in the compost. The estimated additional amounts of these ions contributed by the socks each year ranged from 0.04 to 1.2 kg, thus were likely to be inconsequential. The filter socks contributed to a significant (P and alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide] (18%) concentrations for the tilled watersheds, but this was insufficient to reduce alachlor concentrations to acceptable levels.

  16. A new system for classifying tooth, root and canal anomalies.

    Science.gov (United States)

    Ahmed, H M A; Dummer, P M H

    2017-10-12

    Understanding the normal anatomical features as well as the more unusual developmental anomalies of teeth, roots and root canals is essential for successful root canal treatment. In addition to various types of root canal configuration and accessory canal morphology, a wide range of developmental tooth, root and canal anomalies exists, including C-shaped canals, dens invaginatus, taurodontism, root fusion, dilacerations and palato-gingival grooves. There is a direct association between developmental anomalies and pulp and periradicular diseases that usually require a multidisciplinary treatment approach to achieve a successful outcome. A number of classifications have categorized tooth, root and canal anomalies; however, several important details are often missed making the classifications less than ideal and potentially confusing. Recently, a new coding system for classifying root, root canal and accessory canal morphology has been introduced. The purpose of this article is to introduce a new system for classifying tooth, root and canal anomalies for use in research, clinical practice and training, which can serve as complementary codes to the recently described system for classifying root, as well as main and accessory canal morphology. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  17. Viability of forest fuel transportation in the Finnish rail and waterway networks

    Energy Technology Data Exchange (ETDEWEB)

    Korpinen, O.-J.; Karttunen, K.; Ranta, T. (Lappeenranta Univ. of Technology, Mikkeli (Finland), Dept. of Energy and Environmental Technology), e-mail: olli-jussi.korpinen@lut.fi; Saranen, J. (Lappeenranta Univ. of Technology, Kouvola (Finland), Dept. of Industrial Management), e-mail: juha.saranen@lut.fi; Vaeaetaeinen, K. (Finnish Forest Research Inst., Joensuu (Finland)), e-mail: kari.vaatainen@metla.fi

    2010-07-01

    Energy use of biomass increases as EU's climate policy drives power plants to produce energy from renewable sources. In Finland, increasing the use of forest fuels is one of the key methods in reaching the national targets. Theoretically, the availability of forest fuels exceeds the capacity of power plants. However, the challenge is related to the cost of transporting the biomass to the point of use. The fuel needs to be gathered from hundreds of small roadside storages and comminuted to chips in various locations. When the hauling distance increases, supply via terminals and using rail or waterways instead of trucks in long-distance transportation becomes an option to consider. The purpose of the work was to evaluate alternative logistic solutions for forest fuel supply based on rail and waterway transports. The evaluation was performed using simulations of transport chains for deriving the forest fuel transportation cost. The results indicate that to be profitable systems, both supply methods need high volumes of biomass available for transport. (orig.)

  18. Efficiency of inland waterway container terminals : Stochastic frontier and data envelopment analysis to analyze the capacity design- and throughput efficiency

    NARCIS (Netherlands)

    Wiegmans, Bart; Witte, P.A.

    2017-01-01

    Although terminal efficiency has been thoroughly studied for deep-sea container ports and terminals, up till now, there has been little scientific literature on the efficiency of inland waterway container terminals (IWTs). This paper therefore focuses on determining and analyzing terminal

  19. Anterior canal lithiasis: diagnosis and treatment.

    Science.gov (United States)

    Casani, Augusto Pietro; Cerchiai, Niccolò; Dallan, Iacopo; Sellari-Franceschini, Stefano

    2011-03-01

    To describe the clinical and oculographic features in patients with anterior semicircular canal benign paroxysmal positional vertigo and to determine the efficacy of a canalith repositioning procedure for its management. Case series with chart review of patients presenting positional vertigo and positional downbeating nystagmus during a 2-year period. Outpatients' tertiary referral center for balance disorders. Eighteen patients suffering from positional vertigo and presenting positional downbeating nystagmus were treated with a maneuver based on a modification of the procedure proposed by Crevits. disappearance of positional downbeating nystagmus. Positional downbeating nystagmus was elicited unilaterally with the Dix-Hallpike maneuver in 6 cases. In 4 patients, it was triggered by both left and right Dix-Hallpike tests. In 8 patients, the positional nystagmus was elicited by a straight head-hanging maneuver. The positional nystagmus was purely downbeating in 12 patients. In the remaining, a torsional component was detected. After the treatment, only 1 patient showed positional nystagmus at 30 days. In anterior canal benign paroxysmal positional vertigo, the presence of a positional downbeating nystagmus in response to positional tests is key for diagnosis. In a significant number of patients, the affected side may not be detected because of the inconstant presence of a torsional component. Treatment with a simplified maneuver based on Crevits's technique can be considered an effective method for the treatment of anterior canal lithiasis, especially when the affected side cannot be detected clearly.

  20. Port and Waterways Safety Assessment Workshop Report, New York

    Science.gov (United States)

    2008-09-01

    River 3rd Avenue Bridge construction activities Trends: • None identified Existing Mitigations: • Local ship drivers know where the rocks are...impacts on vessel navigation are minimized • CG permitting process on bridge construction ensures mid-span lighting and signage is visible

  1. 77 FR 70174 - Waterway Suitability Assessment for Expansion of Liquefied Gas Terminals; Houston and Texas City, TX

    Science.gov (United States)

    2012-11-23

    ... 24, 2012 regarding the company's proposed expansion of its LHG facilities in Houston and Texas City... SECURITY Coast Guard Waterway Suitability Assessment for Expansion of Liquefied Gas Terminals; Houston and Texas City, TX AGENCY: Coast Guard, DHS. ACTION: Notice and request for comments. SUMMARY: In accordance...

  2. 33 CFR 117.635 - Keweenaw Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Keweenaw Waterway. 117.635 Section 117.635 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Michigan § 117.635 Keweenaw Waterway. The draw of the...

  3. 33 CFR 117.393 - Illinois Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Illinois Waterway. 117.393 Section 117.393 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Illinois § 117.393 Illinois Waterway. (a) The draw of...

  4. 77 FR 22769 - Amendment to the Inland Waterways Users Board

    Science.gov (United States)

    2012-04-17

    ... of the Secretary Amendment to the Inland Waterways Users Board AGENCY: DoD. ACTION: Charter Amendment... Waterways Users Board (hereafter referred to as ``the Board''). The Board is authorized by statute, and... of the U.S. inland waterways and inland harbors as defined in Public Law 95-502 and amended by Public...

  5. Panama Canal Watershed Experiment- Agua Salud Project

    Science.gov (United States)

    Stallard, Robert F.; Ogden, Fred L.; Elsenbeer, Helmut; Hall, Jefferson S.

    2010-01-01

    The Agua Salud Project utilizes the Panama Canal’s (Canal) central role in world commerce to focus global attention on the ecosystem services provided by tropical forests. The Canal was one of the great engineering projects in the world. Completed in 1914, after almost a decade of concerted effort, its 80 km length greatly shortened the voyage between the Atlantic and Pacific Oceans. An entire class of ships, the Panamax, has been constructed to maximize the amount of cargo that can be carried in a Canal passage. In today’s parlance, the Canal is a “green” operation, powered largely by water (Table 1). The locks, three pairs on each end with a net lift of 27 meters, are gravity fed. For each ton of cargo that is transferred from ocean to ocean, about 13 tons of water (m3) are used. Lake Gatún forms much of the waterway in the Canal transect. Hydroelectricity is generated at the Gatún dam, whenever there is surplus water, and at Madden Dam (completed in 1936) when water is transferred from Lake Alhajuela to Lake Gatún. The Canal watershed is the source of drinking water for Panama City and Colon City, at either end of the Canal, and numerous towns in between.

  6. 78 FR 4785 - Inland Waterways Navigation Regulation: Sacramento River, CA

    Science.gov (United States)

    2013-01-23

    ... SECURITY Coast Guard 33 CFR Part 162 RIN 1625-AB95 Inland Waterways Navigation Regulation: Sacramento River... be adversely affected by ] removal of the restriction. This rule will update the inland waterways... required for this rule. List of Subjects in 33 CFR Part 162 Navigation (water) and Waterways. For the...

  7. 48 CFR 252.236-7002 - Obstruction of navigable waterways.

    Science.gov (United States)

    2010-10-01

    ... waterways. 252.236-7002 Section 252.236-7002 Federal Acquisition Regulations System DEFENSE ACQUISITION... of Provisions And Clauses 252.236-7002 Obstruction of navigable waterways. As prescribed in 236.570(b)(1), use the following clause: Obstruction of Navigable Waterways (DEC 1991) (a) The Contractor shall...

  8. 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.

  9. TCDD residues in fish and shellfish from U.S. waterways.

    Science.gov (United States)

    Firestone, D; Fehringer, N V; Walters, S M; Kozara, R J; Ayres, R J; Ogger, J D; Schneider, L F; Glidden, R M; Ahlrep, J R; Brown, P J; Ford, S E; Davy, R A; Gulick, D J; McCullough, B H; Sittig, R A; Smith, P V; Syvertson, C N; Barber, M R

    1996-01-01

    TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) in the edible portion of fish and shellfish from various U.S. waterways has been monitored since 1979. Analytical results for the period 1979-1994 are reported. Extracts obtained after column chromatographic and liquid chromatographic cleanup were examined by electron capture detection-gas chromatography (GC), and final quantitation and confirmation were performed by GC/mass spectrometry with multiple ion detection. Analyses of 1623 test samples indicated that TCDD residues in fish and shellfish were not widespread but rather were localized in areas near waste sites, chlorophenol manufacturers, and pulp and paper mills. Analytical results indicated that levels in aquatic species from these sites have been declining steadily. No TCDD (limit of detection and confirmation, 1-2 ppt) has been found in recent years in aquatic species from most Atlantic, Pacific, and Gulf of Mexico sites and Great Lakes other than Lake Ontario and Saginaw Bay (Lake Huron).

  10. A Two-Ocean Bouillabaisse: Science, Politics, and the Central American Sea-Level Canal Controversy.

    Science.gov (United States)

    Keiner, Christine

    2017-11-01

    As the Panama Canal approached its fiftieth anniversary in the mid-1960s, U.S. officials concerned about the costs of modernization welcomed the technology of peaceful nuclear excavation to create a new waterway at sea level. Biologists seeking a share of the funds slated for radiological-safety studies called attention to another potential effect which they deemed of far greater ecological and evolutionary magnitude - marine species exchange, an obscure environmental issue that required the expertise of underresourced life scientists. An enterprising endeavor to support Smithsonian naturalists, especially marine biologists at the Smithsonian Tropical Research Institute in Panama, wound up sparking heated debates - between biologists and engineers about the oceans' biological integrity and among scientists about whether the megaproject represented a research opportunity or environmental threat. A National Academy of Sciences panel chaired by Ernst Mayr failed to attract congressional funding for its 10-year baseline research program, but did create a stir in the scientific and mainstream press about the ecological threats that the sea-level canal might unleash upon the Atlantic and Pacific. This paper examines how the proposed megaproject sparked a scientific and political conversation about the risks of mixing the oceans at a time when many members of the scientific and engineering communities still viewed the seas as impervious to human-facilitated change.

  11. [Canal infection. Ecological theory and repair with osteodentin].

    Science.gov (United States)

    Muñiz, M A; Zeberio, T

    1991-01-01

    The characteristics of the infection in the root canal are analyzed, specially its development before pulpal necrosis. It is inferred that it is an ecological infection with a function: to decompose the necrosis. Inactivating the infection in the canal by the formocresol technique, calcium hidroxide or with the conventional basic treatment in Endodontics, cleaning, washing, disinfecting and, in this case, with partial obturation of the canal, it is possible to induce a reparation with osteodentine that can cover all the free extension of the canal.

  12. H09169: NOS Hydrographic Survey , East Waterway and Portion of Duwamish Waterway, Washington, 1970-11-09

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe...

  13. 76 FR 45421 - Safety Zone; Houma Navigation Canal, From Waterway Mile Markers 19.0 to 20.0, Southwest of Bayou...

    Science.gov (United States)

    2011-07-29

    ... identified as Reach F and Segment 1 of Reach G of the Morganza to the Gulf hurricane protection system. The... the Instruction. This rule establishes a temporary safety zone to protect the public from the dangers...

  14. Bank erosion processes in waterways

    NARCIS (Netherlands)

    Duro, G.; Uijttewaal, W.S.J.; Kleinhans, M; Crosato, A.; Hoitink, A.J.F.; de Ruijsscher, T.V.; Geertsema, T.J.; Makaske, B.; Wallinga, J.; Candel, J.H.J.; Poelman, J.

    2017-01-01

    Waterways serve for several functions besides  transporting goods and people. The ecological  importance of navigable rivers has taken much  attention during recent decades bringing efforts  to improve these natural corridors for fauna and  flora (Boeters et al.,

  15. Geographic Information System (GIS) characterization of benthic and emergent areas in the Intracoastal Waterway, Sarasota County, Florida in 1987 (NODC Accession 0000607)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GIS layer graphically represents algae, seagrass, tidal marshes, mangroves, and oyster bed coverages found throughout the Intracoastal Waterway in Sarasota...

  16. Lateral line canal morphology and signal to noise ratio

    Science.gov (United States)

    Klein, Adrian; Herzog, Hendrik; Bleckmann, Horst

    2011-04-01

    The lateral line system of fish is important for many behaviors, including spatial orientation, prey detection, shoaling, intra specific communication and entraining. The smallest sensory unit of the lateral line is the neuromast that occurs free standing on the skin and in fluid filled canals. With aid of the lateral line fish perceive minute water motions. In their natural habitat fish are not only faced with biotic water motion but also with the abiotic fluctuations caused by various inanimate sources. The detection of meaningful signals is crucial for survival, and therefore animals should be able to separate meaningful signals from noise. Fishes live in various habitats (e.g. in still water or in running water). Therefore it is not surprising that the number and distribution of neuromasts as well as canal dimension, canal shape and canal branching patterns differ among fish species. We studied how lateral line canal parameters influence the filter properties of lateral line canals. To do so we exposed artificial lateral line canals, equipped with artificial neuromasts (sensors), to the vortex street shed by a submerged cylinder and to air bubble noise. We found that certain canal parameters significantly can enhance the signal to noise ratio.

  17. 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.

  18. Traditional and contemporary techniques for optimizing root canal irrigation.

    Science.gov (United States)

    Holliday, Richard; Alani, Aws

    2014-01-01

    Canal irrigation during root canal treatment is an important component of chemo-mechanical debridement of the root canal system. Traditional syringe irrigation can be enhanced by activating the irrigant to provide superior cleaning properties. This activation can be achieved by simple modifications in current technique or by contemporary automated devices. Novel techniques are also being developed, such as the Self-adjusting File (Re-Dent-Nova, Ra'anana, Israel), Ozone (Healozone, Dental Ozone, London, UK), Photoactivated Disinfection and Ultraviolet Light Disinfection. This paper reviews the techniques available to enhance traditional syringe irrigation, contemporary irrigation devices and novel techniques, citing their evidence base, advantages and disadvantages. Recent advances in irrigation techniques and canal disinfection and debridement are relevant to practitioners carrying out root canal treatment.

  19. 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

  20. Kiel Canal: Past and future threats for shipping resulting from precipitation, wind surge and sea level rise

    Science.gov (United States)

    Ganske, Anette; Hüttl-Kabus, Sabine; Möller, Jens; Schade, Nils; Heinrich, Hartmut; Tinz, Birger

    2017-04-01

    The Kiel Canal is the most frequented artificial waterway in the world. It connects the North Sea and the Hamburg Harbor with the Baltic Sea and has a length of about 100 km. The Canal receives its water from the upper catchment of the river Eider. Discharge from the Canal towards the North Sea is via the sluices at Brunsbüttel (90%) into river Elbe and into the Baltic Sea via the sluices at Kiel-Holtenau. A risk of closure of the Canal occurs when high precipitation in the catchment meets high water levels in the river Elbe and/or the Baltic preventing the discharge of excess Canal water. Future sea level rise jointly with other effects such as possibly increasing wind surge and precipitation will close the gap between the inner and outer water levels, so that someday the outside levels will surmount the inner one. The German Federal Ministry of Transport and Digital Infrastructure (BMVI) tasked its internal Network of Experts to run a case study on the evolution of critical water levels in order to estimate risks and vulnerabilities for adaptation measures. First step of the investigation is a search for factors or combination of factors responsible for closures in the past. Candidates are factors such as higher water levels at low tides, high precipitation events on land, soil moisture and human factors like preventive water management measures. Second step will be the search for the natural criteria in climate projections. Here we report on the results of the first step of the case study with a focus on the exit towards the North Sea. There, discharge is possible only during low tide. Presently still sufficient difference in height exists between the levels in the Canal and the river Elbe allowing for a free flow of excess Canal water. Shipping is ceased when levels in the Canal surpass safety limits due to high precipitation events in the catchment jointly with high outer water levels. We used atmospheric data from ERA-Interim reanalysis instead of gauge data

  1. Occurrence and distribution of sediment-associated insecticides in urban waterways in the Pearl River Delta, China.

    Science.gov (United States)

    Li, Huizhen; Tyler Mehler, W; Lydy, Michael J; You, Jing

    2011-03-01

    Sediment-associated pesticides, including organochlorine (OCP), organophosphate (OP), and pyrethroid insecticides, were analyzed in urban waterways in three cities (Guangzhou, Dongguan, and Shenzhen) in the Pearl River Delta (PRD), China. The OCPs represented 27.2% of the detectable insecticides in sediment, and chlordanes, DDTs, and endosulfans were the most frequently detected OCPs. The currently used insecticide chlorpyrifos was the only OP detected above the reporting limit (RL), with concentrations ranging from waterways in China, the current study found cypermethrin was the most abundant insecticide detected in the PRD at concentrations ranging from 1.44 to 219 ng g(-1) dw. Spatially, sediment from more populous and urbanized areas (Shenzhen and Tianhe district in Guangzhou) had higher insecticide residues than less populous agricultural areas. In the more modernized city of Shenzhen, the OCPs were seldom detected, whereas more diverse patterns of pyrethroids were observed. Potential sources of these insecticides, especially the frequently detected pyrethroids, were most likely from pest control during urban landscaping maintenance and from abatement programs targeting mosquitoes and ants. Results suggested that a shift in application pattern and elevated urbanization increased accumulation of currently used insecticides like pyrethroids in sediment, and made them the predominate insecticides in the PRD urban waterways. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Ecogenomics reveals metals and land-use pressures on microbial communities in the waterways of a megacity.

    Science.gov (United States)

    Saxena, Gourvendu; Marzinelli, Ezequiel M; Naing, Nyi N; He, Zhili; Liang, Yuting; Tom, Lauren; Mitra, Suparna; Ping, Han; Joshi, Umid M; Reuben, Sheela; Mynampati, Kalyan C; Mishra, Shailendra; Umashankar, Shivshankar; Zhou, Jizhong; Andersen, Gary L; Kjelleberg, Staffan; Swarup, Sanjay

    2015-02-03

    Networks of engineered waterways are critical in meeting the growing water demands in megacities. To capture and treat rainwater in an energy-efficient manner, approaches can be developed for such networks that use ecological services from microbial communities. Traditionally, engineered waterways were regarded as homogeneous systems with little responsiveness of ecological communities and ensuing processes. This study provides ecogenomics-derived key information to explain the complexity of urban aquatic ecosystems in well-managed watersheds with densely interspersed land-use patterns. Overall, sedimentary microbial communities had higher richness and evenness compared to the suspended communities in water phase. On the basis of PERMANOVA analysis, variation in structure and functions of microbial communities over space within same land-use type was not significant. In contrast, this difference was significant between different land-use types, which had similar chemical profiles. Of the 36 environmental parameters from spatial analysis, only three metals, namely potassium, copper and aluminum significantly explained between 7% and 11% of the variation in taxa and functions, based on distance-based linear models (DistLM). The ecogenomics approach adopted here allows the identification of key drivers of microbial communities and their functions at watershed-scale. These findings can be used to enhance microbial services, which are critical to develop ecologically friendly waterways in rapidly urbanizing environments.

  3. Research note: Mapping spatial patterns in sewer age, material, and proximity to surface waterways to infer sewer leakage hotspots

    Science.gov (United States)

    Hopkins, Kristina G.; Bain, Daniel J.

    2018-01-01

    Identifying areas where deteriorating sewer infrastructure is in close proximity to surface waterways is needed to map likely connections between sewers and streams. We present a method to estimate sewer installation year and deterioration status using historical maps of the sewer network, parcel-scale property assessment data, and pipe material. Areas where streams were likely buried into the sewer system were mapped by intersecting the historical stream network derived from a 10-m resolution digital elevation model with sewer pipe locations. Potential sewer leakage hotspots were mapped by identifying where aging sewer pipes are in close proximity (50-m) to surface waterways. Results from Pittsburgh, Pennsylvania (USA), indicated 41% of the historical stream length was lost or buried and the potential interface between sewers and streams is great. The co-location of aging sewer infrastructure (>75 years old) near stream channels suggests that 42% of existing streams are located in areas with a high potential for sewer leakage if sewer infrastructure fails. Mapping the sewer-stream interface provides an approach to better understand areas were failing sewers may contribute a disproportional amount of nutrients and other pathogens to surface waterways.

  4. Moving fluid mud sondes, optical and acoustic sensing methods in support of coastal waterway dredging

    Science.gov (United States)

    Bostater, Charles R.; Rotkiske, Tyler

    2015-10-01

    Airborne, Satellite and In-Situ optical and acoustical imaging provides a means to characterize surface and subsurface water conditions in shallow marine systems. An important research topic to be studied during dredging operations in harbors and navigable waterways is the movement of fluidized muds before, during and after dredging operations. The fluid movement of the surficial sediments in the form of flocs, muck and mud is important to estimate in order to model the transport of solids material during dredging operations. Movement of highly turbid bottom material creates a lutocline or near bottom nephelometric layers, reduces the penetration of light reaching the water bottom. Monitoring and measurement systems recently developed for use in shallow marine areas, such as the Indian River Lagoon are discussed. Newly developed passive sondes and subsurface imaging are described. Methods and techniques for quantifying the mass density flux of total particulate matter demonstrate the use of multiple sensor systems for environmental monitoring and provide directional fluxes and movement of the fluidized solids. Airborne imaging of dredge site provide wide area surveillance during these activities. Passive sondes, optical imaging and acoustical sensors are used to understand horizontal and vertical mass flux processes. The passive sondes can be directionally oriented and are deployed during optical particle velocimetry system (OPVS) imaging of the flocs, particles and colloidal material motion. Comparison of the image based particle velocities are compared to electromagnetic and acoustic velocity imaging results. The newly developed imaging system provides a pathway for integration of subsurface hyperspectral imaging for particle compositional analysis.

  5. Effects of hydrologic modifications on salinity and formation of hypoxia in the Mississippi River-Gulf Outlet and adjacent waterways, southeastern Louisiana, 2008 to 2012

    Science.gov (United States)

    Swarzenski, Christopher M.; Mize, Scott V.

    2014-01-01

    The Mississippi River-Gulf Outlet (MRGO) was constructed between 1958 and 1968 to provide a safer and shorter route between the Gulf of Mexico and the Port of New Orleans for ocean-going vessels. In 2006, the U.S. Congress directed the U.S. Army Corps of Engineers (USACE) to develop and implement a plan to deauthorize a portion of the MRGO ship channel from its confluence with the Gulf Intracoastal Waterway to the Gulf of Mexico. In 2009, in accordance with plans submitted to Congress, the USACE built a rock barrier across the MRGO near Hopedale, Louisiana. Following Hurricane Katrina, Congress also authorized the USACE to implement the Hurricane Storm Damage Risk Reduction System (HSDRRS) by building structures in the MRGO and adjacent surface waters, to reduce vulnerability of this area to storm surge. The HSDRRS includes the Gulf Intracoastal Waterway-Lake Borgne Surge Barrier and Gate Complex near mile 58 of the deauthorized portion of the MRGO and the Seabrook Gate Complex on the Inner Harbor Navigation Canal (IHNC). By blocking or limiting tidal exchange in the MRGO, these barriers could affect water quality in the MRGO and nearby waters including Lake Pontchartrain, the IHNC, and Lake Borgne. In 2008, the U.S. Geological Survey, in cooperation with the USACE, began a study to document the effects of the construction activities on salinity and dissolved oxygen in these surface waters. Data were collected from August 2008 through October 2012. Completion of the rock barrier in the vicinity of mile 35 in July 2009 reduced hydrologic circulation and separated the MRGO into two distinct salinity regimes, with substantially fresher conditions prevailing upstream from the rock barrier. The rock barrier also contributed to a zone of hypoxia (dissolved oxygen less than 2 milligrams per liter) that formed along the channel bottom during the warmer summer months in each year of this monitoring; the zone was much more developed downstream from the rock barrier. The most

  6. Genetic and phenotypic diversity of Ralstonia solanacearum biovar 2 strains obtained from Dutch waterways.

    Science.gov (United States)

    Stevens, Patricia; van Elsas, Jan Dirk

    2010-02-01

    A novel set of Ralstonia solanacearum biovar 2 isolates was obtained, at several sampling occasions, from Dutch waterways, sediment and bittersweet plants and their genetic and phenotypic diversity was investigated. As reference strains, two previously-described strains obtained from diseased potato plants, denoted 1609 (The Netherlands) and 715 (Bangladesh), were included in the analyses. All novel isolates showed BOX and GTG5 PCR based genomic profiles similar to those of the reference strains. Also, PCR-restriction fragment length polymorphism analysis of the phcA and hrp genomic regions, as well as sequence analysis of six selected genomic loci, revealed great homogeneity across the strains. In contrast, pulsed field gel electrophoresis of restricted genomic DNA revealed the distribution of all strains across four groups, denoted pulsotypes A through D (pulsotypes C and D had one representative each). Moreover, pulsotype B, consisting of five strains, could be separated from the other pulsotypes by a divergent genomic fingerprint when hybridized to a probe specific for insertion element ISRso3. Representatives of pulsotypes A, B and C were selected for growth and metabolic studies. They showed similar growth rates when grown aerobically in liquid media. Assessment of their metabolic capacity using BIOLOG GN-2 revealed a reduced utilization of compounds as compared to the reference strains, with some variation between strains.

  7. Modeling and measurement of root canal using stereo digital radiography

    Science.gov (United States)

    Analoui, Mostafa; Krisnamurthy, Satthya; Brown, Cecil

    2000-04-01

    Determining root canal length is a crucial step in success of root canal treatment. Root canal length is commonly estimated based on pre-operation intraoral radiography. 2D depiction of a 3D object is the primary source of error in this approach. Techniques based on impedance measurement are more accurate than radiographic approaches, but do not offer a method for depicting the shape of canal. In this study, we investigated a stererotactic approach for modeling and measurement of root canal of human dentition. A weakly perspective model approximated the projectional geometry. A series of computer-simulated objects was used to test accuracy of this model as the first step. The, to assess the clinical viability of such an approach, endodontic files inserted in the root canal phantoms were fixed on an adjustable platform between a radiographic cone and an image receptor. Parameters of projection matrix were computed based on the relative positions of image receptors, focal spot, and test objects. Rotating the specimen platform from 0 to 980 degrees at 5-degree intervals set relative angulations for stereo images. Root canal is defined as the intersection of two surfaces defined by each projection. Computation of error for length measurement indicates that for angulations greater than 40 degrees the error is within clinically acceptable ranges.

  8. A numerical study on ship-ship interaction in shallow and restricted waterway

    Directory of Open Access Journals (Sweden)

    Sungwook Lee

    2015-09-01

    Full Text Available In the present study, a numerical prediction method on the hydrodynamic interaction force and moment between two ships in shallow and restricted waterway is presented. Especially, the present study proposes a methodology to overcome the limitation of the two dimensional perturbation method which is related to the moored-passing ship interaction. The validation study was performed and compared with the experiment, firstly. Afterward, in order to propose a methodology in terms with the moored-passing ship interaction, further studies were performed for the moored-passing ship case with a Reynolds Averaged Navier-Stokes (RANS calculation which is using OpenFOAM with Arbitrary Coupled Mesh Interface (ACMI technique and compared with the experiment result. Finally, the present study proposes a guide to apply the two dimensional perturbation method to the moored-passing ship interaction. In addition, it presents a possibility that the RANS calculation with ACMI can applied to the ship-ship interaction without using a overset moving grid technique.

  9. The Nicaragua Canal:Security And Economic Boom Or Bust

    Science.gov (United States)

    2014-04-01

    but is the property of the United States government. Abstract Since the 1800s nations and entrepreneurs have sought a maritime route across...across Central America to compete with the Panama Canal and thus secure his future with Nicaragua. Since the 1800s nations and entrepreneurs have...for the environmental effects that construction and operation of a canal could have on the regional ecosystem . As a result, environmentalists have

  10. Unusal canal configuration in maxillary and mandibular second molars

    Directory of Open Access Journals (Sweden)

    Ramachandran Ragunathan

    2016-01-01

    Full Text Available This clinical article describes three different case reports of maxillary and mandibular second molars with the unusual anatomy of single root with a single canal and their endodontic management. An unusual case of bilateralism is observed in the first two cases in the form of single-rooted second mandibular molars in both the quadrant of the same patient. The presence of maxillary second molar with single root and single canal in the third case is unusual.

  11. Biomarker responses and PAH ratios in fish inhabiting an estuarine urban waterway.

    Science.gov (United States)

    Duarte, Rafael Mendonça; Sadauskas-Henrique, Helen; de Almeida-Val, Vera Maria Fonseca; Val, Adalberto Luis; Nice, Helen Elizabeth; Gagnon, Marthe Monique

    2017-10-01

    Many cities worldwide are established adjacent to estuaries and their catchments resulting in estuarine contamination due to intense anthropogenic activities. The aim of this study was to evaluate if fish living in an estuarine urban waterway were affected by contamination, via the measurement of a suite of biomarkers of fish health. Black bream (Acanthopagrus butcheri) were sampled in a small urban embayment and a suite of biomarkers of fish health measured. These were condition factor (CF), liver somatic index (LSI), gonadosomatic index (GSI), hepatic EROD activity, polycyclic aromatic hydrocarbon (PAH) biliary metabolites, serum sorbitol dehydrogenase (s-SDH) and branchial enzymes cytochrome C oxidase (CCO), and lactate dehydrogenase (LDH) activities. The biomarkers of exposure EROD activity, and pyrene- and B(a)P-type biliary metabolites confirmed current or recent exposure of the fish and that fish were metabolizing contaminants. Relative to a reference site, LSI was higher in fish collected in the urban inlet as was the metabolic enzyme LDH activity. CF, GSI, s-SDH, CCO, and naphthalene-type metabolites were at similar levels in the urban inlet relative to the reference site. PAH biliary metabolite ratios of high-molecular-weight to low-molecular-weight suggest that fish from the urban inlet were exposed to pyrogenic PAHs, likely from legacy contamination and road runoff entering the embayment. Similarly, the sediment PAH ratios and the freshness indices suggested legacy contamination of a pyrogenic source, likely originating from the adjacent historic gasworks site and a degree of contamination of petrogenic nature entering the inlet via storm water discharge. Biomarkers of exposure and effect confirmed that black bream collected in the Claisebrook Cove inlet, Western Australia, are currently exposed to contamination and are experiencing metabolic perturbations not observed in fish collected at a nearby reference site. © 2017 Wiley Periodicals, Inc.

  12. Navigable Waterway Network Node Locations

    Data.gov (United States)

    Department of Homeland Security — The National Waterway Network is a comprehensive network database of the nation's navigable waterways. The data set covers the 48 contiguous states plus the District...

  13. Heterochrony, modularity, and the functional evolution of the mechanosensory lateral line canal system of fishes.

    Science.gov (United States)

    Bird, Nathan C; Webb, Jacqueline F

    2014-01-01

    The canals of the mechanosensory lateral line system are components of the dermatocranium, and demonstrate phenotypic variation in bony fishes. Widened lateral line canals evolved convergently in a limited number of families of teleost fishes and it had been hypothesized that they evolved from narrow canals via heterochrony and explore modularity in the lateral line system. Two species of cichlids with different canal phenotypes were used to test a hypothesis of heterochrony. Histological material prepared from ontogenetic series of Aulonocara stuartgranti (widened canals) and Tramitichromis sp. (narrow canals) was analyzed using ANCOVA to determine rates of increase in canal diameter and neuromast size (length, width) and to compare the timing of onset of critical stages in canal morphogenesis (enclosure, ossification). A faster rate of increase in canal diameter and neuromast width (but not length), and a delay in onset of canal morphogenesis were found in Aulonocara relative to Tramitichromis. However, rates of increase in canal diameter and neuromast size among canals, among canal portions and among canals segments reveal similar trends within both species. The evolution of widened lateral line canals is the result of dissociated heterochrony - acceleration in the rate of increase of both canal diameter and neuromast size, and delay in the onset of canal morphogenesis, in Aulonocara (widened canals) relative to Tramitichromis (narrow canals). Common rates of increase in canal diameter and neuromast size among canal portions in different dermatocranial bones and among canal segments reflect the absence of local heterochronies, and suggest modular integration among canals in each species. Thus, canal and neuromast morphology are more strongly influenced by their identities as features of the lateral line system than by the attributes of the dermatocranial bones in which the canals are found. Rate heterochrony manifested during the larval stage ensures that the

  14. 33 CFR 162.75 - All waterways tributary to the Gulf of Mexico (except the Mississippi River, its tributaries...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false All waterways tributary to the... Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.75 All waterways tributary to the Gulf of Mexico (except the...

  15. National Status and Trends: Bioeffects Program - Sabine Lake, Texas Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The toxicity of sediments in Sabine Lake, Texas, and adjoining Intracoastal Waterway canals was determined as part of bioeffects assessment studies managed by NOAA's...

  16. 33 CFR 207.180 - All waterways tributary to the Gulf of Mexico (except the Mississippi River, its tributaries...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false All waterways tributary to the... DEFENSE NAVIGATION REGULATIONS § 207.180 All waterways tributary to the Gulf of Mexico (except the... apply to: (1) Waterways. All navigable waters of the U.S. tributary to or connected by other waterways...

  17. DETERMINATION OF THE DISTRIBUTION AND INVENTORY OF RADIONUCLIDES WITHIN A SAVANNAH RIVER SITE WATERWAY

    Energy Technology Data Exchange (ETDEWEB)

    Hiergesell, R.; Phifer, M.

    2012-11-09

    An investigation was conducted to evaluate the radionuclide inventory within the Lower Three Runs (LTR) Integrator Operable Unit (IOU) at the U.S. Department of Energy’s (DOE’s) Savannah River Site (SRS). The scope of this effort included the analysis of previously existing sampling and analysis data as well as additional streambed and floodplain sampling and analysis data acquired to delineate horizontal and vertical distributions of the radionuclide as part of the ongoing SRS environmental restoration program, and specifically for the LTR IOU program. While cesium-137 (Cs-137) is the most significant and abundant radionuclide associated with the LTR IOU it is not the only radionuclide, hence the scope included evaluating all radionuclides present and includes an evaluation of inventory uncertainty for use in sensitivity and uncertainty analyses. The scope involved evaluation of the radionuclide inventory in the P-Reactor and RReactor cooling water effluent canal systems, PAR Pond (including Pond C) and the floodplain and stream sediment sections of LTR between the PAR Pond Dam and the Savannah River. The approach taken was to examine all of the available Sediment and Sediment/Soil analysis data available along the P- and R-Reactor cooling water re-circulation canal system, the ponds situated along those canal reaches and along the length of LTR below Par Pond dam. By breaking the IOU into a series of sub-components and sub-sections, the mass of contaminated material was estimated and a representative central concentration of each radionuclide was computed for each compartment. The radionuclide inventory associated with each sub-compartment was then aggregated to determine the total radionuclide inventory that represented the full LTR IOU. Of special interest was the inventory of Cs-137 due to its role in contributing to the potential dose to an offsite member of the public. The overall LTR IOU inventory of Cs-137 was determined to be 75.5 Ci, which is similar

  18. The cooperation relationship study on the golden waterway of the Yangtze River and economic development along the Yangtze River

    Science.gov (United States)

    Du, Linan; Zhang, Jianbao

    2017-10-01

    The paper makes use of 2006-2015-time sequence as data to build up a two-evaluation index system of the construction of golden waterway of Yangtze River and economy development along the Yangtze River. Through building the cooperated development mode, there is quantitative evaluation of the cooperation development degree of shipping of Yangtze River and the economy along the river. The result shows that the cooperation relationship is in steady upward trend; the cooperation development degree of three regions shows certain feature of crust; the cooperation development degree of 9 provinces and 2 cities in Yangtze River Economic Belt has obvious space difference.

  19. The potential and limitations of linking biological monitoring data and restoration needs of urbanized waterways: a case study.

    Science.gov (United States)

    Kemp, Stanley

    2014-06-01

    The implementation of effective strategies to mitigate the impacts of urbanization on waterways represents a major global challenge. Monitoring data plays an important role in the formulation of these strategies. Using monitoring and historical data compiled from around an urban area (Baltimore, USA), this paper is an assessment of the potential and limitations of the use of fish assemblage monitoring data in watershed restoration. A discriminant analysis between assemblages from urban and reference sites was used to determine faunal components which have been reduced or eliminated from Baltimore area waterways. This analysis produced a strong discrimination between fish assemblages from urban and reference sites. Species primarily associated with reference sites varied taxonomically and ecologically, were generally classified as pollution intolerant, and were native. Species associated with urbanized sites were also native, varied taxonomically and ecologically, and were mixed in pollution tolerance. One factor linking most species associated with reference sites was spawning mode (lithophilic). Spawning habitat limitations may be the mechanism through which these species have been reduced in the urbanized faunas. While this presents a strong general hypothesis, information regarding the specific habitat requirements and responses to urbanization of these species is limited. This represents a limitation to producing effective restoration strategies based on exact goals and targets. Without these, determining the type and number of restoration activities required to restore ecological communities remains problematic.

  20. Significance of temporal bone CT scan for exposure of the facial canal and the lateral semicircular canal in cholesteatoma

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Ki Joon; Kim, Dong Jin; Kim, Myung Soon; Kim, Young Ju; Kweon, Joon [Wonju College of Medicine, Yonsei University, Wonju (Korea, Republic of)

    1991-09-15

    By reviewing retrospectively the HRCT findings in 130 surgically proven cases of chronic otitis media with cholesteatoma, we estimated the sensitivity, specificity, and positive predictability of the HRCT compared to surgical findings. For exposure of the facial canal, the sensitivity, specificity, and positive predictability was 59.7%, 84.9%, and 85.2% respectively. For exposure of the lateral semicircular canal, the sensitivity was 80.6%, the specificity 99.0%, and the positive predictability 96.2%. Conclusively, the diagnostic accuracy of preoperative temporal bone CT regarding the state of the lateral semicircular canal seems to be highly reliable. Gross invasion of the facial canal can be usually detected. However, relatively low sensitivity suggests that evaluation of the ultra-thin structures of the tympanic segment is often problematic.

  1. Cervical spinal canal narrowing and cervical neurologi-cal injuries

    Directory of Open Access Journals (Sweden)

    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

  2. The effect of working length and root canal preparation technique on crack development in the apical root canal wall.

    Science.gov (United States)

    Adorno, C G; Yoshioka, T; Suda, H

    2010-04-01

    To evaluate the effects of working length and root canal preparation technique on crack development in the apical root canal wall. Seventy extracted mandibular premolars were mounted in a resin block with simulated periodontal ligaments and divided into seven groups according to preparation technique and working length: group A, step-back preparation with stainless steel files with working length set at the apical foramen and defined as root canal length (CL); group B, same as for A, except that the working length was CL-1 mm; group C, crown-down preparation with Profile instruments followed by an apical enlargement sequence with CL as working length and group D, same as for C, except that the working length was CL-1 mm. Groups E, F and G served as controls. Groups E and F were prepared only with the crown-down sequence up to CL and CL-1 mm, respectively. Group G was left unprepared. Digital images of the apical root surface (AS) were recorded before preparation, immediately after instrumentation and after removing the apical 1 mm (AS-1 mm) and 2 mm (AS-2 mm) of the root end. Working length significantly affected crack development at AS (P crack development at AS-1 mm (P crack development on the canal wall. Root canal preparation alone, regardless of the technique used, can potentially generate cracks on the apical root canal wall as well as the apical surface. Working 1- mm short of the apical foramen might produce fewer cracks in the apical region.

  3. The role of classification and reference vessels in the design of inland fairways for commercial vessels – contribution to the Workshop of WG 141 Design Guidelines for Inland Waterways

    NARCIS (Netherlands)

    Koedijk, O.C.

    2015-01-01

    The Pianc WG 141 is proceeding in the conception of Design Guidelines for Inland Waterways. WG 141 aims to produce its first draft in the end of 2015. Part of the forseen content are classification of waterways and the object of reference vessels. The role of those subjects will be presented and

  4. CT and MR Imagings of Semicircular Canal Aplasia

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Necrotic pulp tissue dissolution by passive ultrasonic irrigation in simulated accessory canals: impact of canal location and angulation.

    Science.gov (United States)

    Al-Jadaa, A; Paqué, F; Attin, T; Zehnder, M

    2009-01-01

    To evaluate whether passive ultrasonic irrigation (PUI) of 2.5% NaOCl would dissolve necrotic pulp tissue from simulated accessory root canals (SACs) better than passive placement of the irrigant, when temperature was equilibrated between the two treatments. Transparent root canal models (n = 6) were made from epoxy resin. SACs of 0.2 mm diameter were placed at defined angles and positions in the mid-canal and apical area. SACs were filled with necrotic bovine pulp tissue. PUI was performed five times for 1 min each with irrigant replenishment after every minute. Main canal temperature was measured after each minute, and a digital photograph was taken. In control experiments, mock treatments were performed with the same set-up without activation of the file using heated NaOCl to mimic the temperature created by PUI. Experiments were repeated five times. Digital photographs were analysed for the distance of dissolved tissue into the SACs in mm. Overall comparison (sum of dissolved tissue from all five accessory canals) between treatments was performed using paired t-test. Differences between SAC angulation and position after PUI were investigated using anova/Bonferroni (alpha temperature in the main canal to 53.5 +/- 2.7 degrees C after the fifth minute. PUI dissolved a total of 6.4 +/- 2.1 mm, mock treatment controlled for heat: 1.4 +/- 0.6 mm (P temperature.

  6. Microstructure and wettability of root canal dentine and root canal filling materials after different chemical irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Antonijevic, Djordje; Milovanovic, Petar [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Brajkovic, Denis [Department of Dentistry, Faculty of Medical Sciences, University of Kragujevac, Kragujevac (Serbia); Ilic, Dragan [Department of Restorative Medicine, School of Dental Medicine, University of Belgrade, Belgrade (Serbia); Hahn, Michael; Amling, Michael [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany); Rakocevic, Zlatko [Laboratory for Atomic Physics, Institute for Nuclear Science “Vinca”, University of Belgrade, Belgrade (Serbia); Djuric, Marija [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Busse, Björn, E-mail: b.busse@uke.uni-hamburg.de [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany)

    2015-11-15

    Graphical abstract: - Highlights: • Different irrigation solutions and disinfectants were used for treatment of root canal dentine and gutta-percha points. • Materials surface characteristics were assessed using quantitative backscattered electron imaging, reference point indentation, and contact angle analyzer. • The most significant differences in mineralization, indentation, and adhesive outcomes were observed after ethylenediaminetetraacetic acid treatment. • Irrigation solutions confer to superior sealing ability of endodontic filling materials. • Micromechanical characteristics of dentine after irrigation are considerable reduced. - Abstract: The objective of this study was to determine the effects of various irrigation solutions on root canal dentine and gutta-percha surface properties. In addition, the effects of disinfectant chemicals on the wettability and surface morphological properties of the filling materials were evaluated. Ethylenediaminetetraacetic acid (EDTA), citric acid, and ozone were employed as irrigation solutions for dentine and gutta-percha treatment. Thereafter, the samples’ microstructure, degree of mineralization, and mechanical properties were assessed by means of quantitative backscattered electron imaging (qBEI) and reference point indentation (RPI). A contact angle analyzer was used to measure adhesion on the tested materials. Here, EDTA had the most significant affect on both the mechanical properties and the adhesive behavior of dentine. Citric acid did not affect dentine wettability, whereas the indentation properties and the mineralization were reduced. Similar effects were observed when ozone was used. The dentinal tubules were significantly widened in citric acid compared to the ozone group. EDTA causes considerable micromechanical surface alteration of dentine and gutta-percha, but represents the best option in clinical cases where a high adhesiveness of the filling materials is desired.

  7. Analysis of sediments and soils for chemical contamination for the design of US Navy homeport facility at East Waterway of Everett Harbor, Washington. Final report. [Macoma inquinata; Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J.W.; Crecelius, E.A.

    1985-03-01

    Contaminated sediments in the East Waterway of Everett Harbor, Washington, are extremely localized; they consist of a layer of organically-rich, fine sediments overlying a relatively cleaner, more sandy native material. The contaminated layer varies in thickness throughout the waterway from as much as 2 meters to only a few centimeters. Generally, the layer is thicker and more contaminated at the head of the waterway (northern end) and becomes thinner and less contaminated as one proceeds southerly out of the waterway and into Port Gardner. These sediments contain elevated levels of heavy metals and polynuclear aromatic hydrocarbons (PAH) and scattered concentrations of polychlorinated biphenyls (PCB). Approximately 500,000 cubic yards of material exhibit elevated chemical contamination compared to Puget Sound background levels. The contaminated sediments in this waterway require biological testing before decisions can be made regarding the acceptability of unconfined disposal.

  8. Partial ear canal ablation and lateral bulla osteotomy in rabbits.

    Science.gov (United States)

    Eatwell, K; Mancinelli, E; Hedley, J; Keeble, E; Kovalik, M; Yool, D A

    2013-06-01

    Six lop rabbits were presented with clinical signs of otitis media or externa. The presence of disease was confirmed by computerized tomography examination, with two rabbits suffering from bilateral disease. The rabbits were anaesthetized and underwent surgery of the affected bulla. Rabbits with bilateral disease had a minimum of 2 weeks between procedures. A single vertical incision was made over the base of the vertical canal, which was bluntly dissected free from surrounding tissue. The ventral portion of the vertical canal was removed and a lateral bulla osteotomy was performed. The mucosa at the base of the dorsal vertical canal was apposed and the aural cartilage sutured to form a blind-ending pouch open at the pretragic incisure. Histopathological samples taken from the dorsal margin of the vertical canal yielded subtle and non-specific changes in the six samples submitted. All rabbits were discharged within 48 hours of surgery. The cosmetic outcome was excellent with animals retaining visually normal aural anatomy. The partial ear canal ablation/lateral bulla osteotomy procedure is quick and has a good cosmetic result when performed in rabbits. © 2013 British Small Animal Veterinary Association.

  9. Assessing the risks of aquatic species invasions via European inland waterways: from concepts to environmental indicators.

    Science.gov (United States)

    Panov, Vadim E; Alexandrov, Boris; Arbaciauskas, Kestutis; Binimelis, Rosa; Copp, Gordon H; Grabowski, Michal; Lucy, Frances; Leuven, Rob S E W; Nehring, Stefan; Paunović, Momir; Semenchenko, Vitaliy; Son, Mikhail O

    2009-01-01

    Over the past century, the potential for aquatic species to expand their ranges in Europe has been enhanced both as a result of the construction of new canals and because of increased international trade. A complex network of inland waterways now connects some previously isolated catchments in southern (Caspian, Azov, Black, Mediterranean seas) and northern (Baltic, North, Wadden, White seas) Europe, and these waterways act as corridors for nonnative species invasions. We have developed a conceptual risk assessment model for invasive alien species introductions via European inland waterways, with specific protocols that focus on the development of environmental indicators within the socioeconomic context of the driving forces-pressures-state-impact-response framework. The risk assessment protocols and water quality indicators on alien species were tested for selected ecosystems within 3 main European invasion corridors, and these can be recommended for application as part of the Common Implementation Strategy of the European Commission Water Framework Directive, which aims to provide a holistic risk-based management of European river basins. The conceptual structure of the online Risk Assessment Toolkit for aquatic invasive alien species is provided and includes 3 main interlinked components: online risk assessment protocols, an early warning system, and an information transmitter for risk communication to end users.

  10. Macroanatomic and radiologic characteristics of the superior genial spinal foramen and its bony canal

    OpenAIRE

    Vandewalle, Giovani; Liang, Xin; JACOBS, Romain; Lambrichts, Ivo

    2006-01-01

    Purpose: To determine the incidence, size, location, course, and content of the superior genial spinal foramen and its bony canal. Materials and Methods: Three hundred eighty dry human cadaver mandibles were morphometrically analyzed by measuring the distance from the foramen to the mandibular base and the size of the foramen and bony canal. Radiologically, the course of the bony canal and its relation to the mandibular incisive canal were investigated after injecting contrast medium (Omnipaq...

  11. [Benign postural vertigo and nystagmus of the horizontal semicircular canal].

    Science.gov (United States)

    Waespe, W

    1997-02-22

    Benign paroxysmal vertigo and nystagmus are induced not only by the posterior but also by the horizontal semicircular canal. Benign positional nystagmus of the horizontal canal is more often observed than was previously thought. In 10 patients we analyzed the characteristics and the variability of nystagmus which accompanies positional vertigo of the horizontal canal. There are two forms of nystagmus: primary-geotropic, most often paroxysmal nystagmus (7 patients), and primary-apogeotropic, non-paroxysmal nystagmus (3 patients). Interestingly, in 2 patients with the primary-apogeotropic form the nystagmus converted during the examination into the primary-geotropic form. The reverse was not observed. We discuss the possible pathophysiological mechanisms which could be relevant for provoking manoeuvres.

  12. Morphological examination of the obturator notch and canal in Cervidae.

    Science.gov (United States)

    Tae, Hyun-Jin; Park, Byung-Yong; Kim, In-Shik; Ahn, Dongchoon

    2014-05-01

    The purpose of this study was to investigate gross findings of the obturator notch (ON) and obturator canal (OC) in Cervidae. A total of 183 pelvic girdles from 26 species of deer were examined, and the obturator canal (OC) was classified into 4 types based on the degree of separation from the obturator foramen (OF). The deep ON was observed primarily in the subfamily Capreolinae (telemetacarpal deer). The small bony OC was frequently observed in Hydropotes inermis, Mazama gouazoubira and Ozotoceros bezoarticus. A canal without a tubercle or bony bridge structure was mainly observed in the subfamily Cervinae (plesiometacarpal deer). These results suggest that the deep ONs or the OCs separated by bony structures are more common in telemetacarpal rather than plesiometacarpal deer.

  13. canal24

    Data.gov (United States)

    California Department of Resources — 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...

  14. Ligament structures in the tarsal sinus and canal.

    Science.gov (United States)

    Li, Shu-Yuan; Hou, Zhi-Dian; Zhang, Peng; Li, Hong-Liang; Ding, Zi-Hai; Liu, Yu-Jie

    2013-12-01

    The concrete anatomy and functional characteristics of the subtalar ligaments have been a matter of debate that some believe has hampered the progress of clinical ligament reconstruction. In 32 fresh-frozen cadaver feet, the course of the inferior extensor retinaculum (IER) and other subtalar ligaments was carefully measured and photographed both from the portal of the tarsal sinus and from a posterior view. The IER inserted inside the tarsal sinus and canal by means of 3 roots: a lateral, an intermediate, and a medial one. These roots, along with the tarsal canal, divided the subtalar space into 3 parts. In front of the IER and inside the tarsal sinus, the thick cervical ligament (CL) lay at a 45-degree angle to the calcaneus. Behind the IER and inside the posterior capsule, in most cases (25 of 32 specimens), the posterior capsular ligament (PCaL) lay directly in front of the posterior talocalcaneal facet. Inside the tarsal canal, the fan-shaped medial root of the IER spread from outside upper lateral to lower medial, and the interosseous talocalcaneal ligament (ITCL) ran from upper medial to lower lateral; fibers of these 2 ligaments blended tightly together to form a V-shaped ligament complex. Just anterior to this complex in some cases (20 of 32 specimens), a short narrow upright ligament, the tarsal canal ligament (TCL), was located behind the middle talocalcaneal joint. The results of this study show that the CL is the primary ligament in the tarsal sinus and that the ITCL is a thin single band rather than a strong bilaminar ligament located inside the tarsal canal. Instead, the medial root of the IER is the primary ligamentous structure in the tarsal canal. The anatomical description provided here may provide a more accurate theoretical foundation for clinical subtalar stability restoration.

  15. Shape and Deformation Analysis of the Human Ear Canal

    DEFF Research Database (Denmark)

    Darkner, Sune

    is on the extraction and analysis of the shape and deformation of the ear canal due to movements of the mandible, leaning over, and turning of the head. Methods for surface registration with focus on non-rigid registration are presented, as well as a wide range of statistical methods used for analyzing the shapes...... and deformation fields. The results show that the ear canal changes shape significantly in all subjects and that the deformation is more complicated than previously described in the literature. It is shown that the deformation at specific locations in the ear is significantly correlated to comfort issues reported...

  16. 78 FR 7670 - Safety Zone; Indian Street Bridge Construction, St. Lucie Canal, Palm City, FL

    Science.gov (United States)

    2013-02-04

    ...The Coast Guard is establishing a temporary safety zone on the St. Lucie Canal, Palm City, Florida to provide for the safety of life and vessels on a narrow waterway during bridge construction for the Indian Street Bridge. Persons and vessels are prohibited from entering, transiting through, anchoring in, or remaining within the safety zone unless authorized by the Captain of the Port Miami or a designated representative.

  17. 33 CFR 117.287 - Gulf Intracoastal Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Gulf Intracoastal Waterway. 117.287 Section 117.287 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Waterway. (a) Public vessels of the United States and tugs with tows must be passed through the drawspan of...

  18. 33 CFR 117.733 - New Jersey Intracoastal Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false New Jersey Intracoastal Waterway. 117.733 Section 117.733 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... Intracoastal Waterway. (a) The draw of the Route 35 Bridge, mile 1.1 across Manasquan River at Brielle, shall...

  19. 33 CFR 117.968 - Gulf Intracoastal Waterway.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Gulf Intracoastal Waterway. 117.968 Section 117.968 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.968 Gulf Intracoastal Waterway...

  20. Morphology of the mandibular canal and the angulation between the mandibular and mental canals in dry skulls

    DEFF Research Database (Denmark)

    Pálsson, S R; Kjaer, I

    2008-01-01

    The aim of this study was to analyse the correlation between external and internal mandibular morphology in adult or adolescent normal anthropological mandibles. Lateral radiographs of 31 symmetrical mandibles were analysed. The external morphology was defined by the gonial and beta-angles....... In order to analyse internal morphology, a metallic pin was placed in the mental canal on the left side before radiography. The angle between the mental and the mandibular canals was termed the 'mental angle' and that expressing the curvature of the mandibular canal, the 'mandibular angle'. Spearman...... correlation analysis was used to investigate the relationships between the angles. Internal morphology: a statistically significant correlation was found between the mental and mandibular angles (correlation coefficient: -0.60, P=0.0004). When the mental angle was narrow, the mandibular angle tended...

  1. Diel variation in detection and vocalization rates of king (Rallus elegans) and clapper (Rallus crepitans) rails in intracoastal waterways

    Science.gov (United States)

    Stiffler, Lydia L.; Anderson, James T.; Welsh, Amy B.; Harding, Sergio R.; Costanzo, Gary R.; Katzner, Todd

    2017-01-01

    Surveys for secretive marsh birds could be improved with refinements to address regional and species-specific variation in detection probabilities and optimal times of day to survey. Diel variation in relation to naïve occupancy, detection rates, and vocalization rates of King (Rallus elegans) and Clapper (R. crepitans) rails were studied in intracoastal waterways in Virginia, USA. Autonomous acoustic devices recorded vocalizations of King and Clapper rails at 75 locations for 48-hr periods within a marsh complex. Naïve King and Clapper rail occupancy did not vary hourly at either the marsh or the study area level. Combined King and Clapper rail detections and vocalizations varied across marshes, decreased as the sampling season progressed, and, for detections, was greatest during low rising tides (P < 0.01). Hourly variation in vocalization and detection rates did not show a pattern but occurred between 7.8% of pairwise comparisons for detections and 10.5% of pairwise comparisons for vocalizations (P < 0.01). Higher rates of detections and vocalizations occurred during the hours of 00:00–00:59, 05:00–05:59, 14:00–15:59, and lower rates during the hours of 07:00–09:59. Although statistically significant, because there were no patterns in these hourly differences, they may not be biologically relevant and are of little use to management. In fact, these findings demonstrate that surveys for King and Clapper rails in Virginia intracoastal waterways may be effectively conducted throughout the day.

  2. 33 CFR 329.7 - Intrastate or interstate nature of waterway.

    Science.gov (United States)

    2010-07-01

    ... of waterway. 329.7 Section 329.7 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF... or interstate nature of waterway. A waterbody may be entirely within a state, yet still be capable of... of bearing interstate commerce, are located in only one of the states, the entirety of the waterway...

  3. 75 FR 24740 - Recovery Policy RP9523.5, Debris Removal From Waterways

    Science.gov (United States)

    2010-05-05

    ... SECURITY Federal Emergency Management Agency Recovery Policy RP9523.5, Debris Removal From Waterways AGENCY... notice of the availability of the final Recovery Policy RP9523.5, Debris Removal from Waterways. DATES... guidance for determining the eligibility of debris removal from navigable waterways, the coastal and inland...

  4. Radiographic Localization of the Mental Foramen and Mandibular Canal

    Directory of Open Access Journals (Sweden)

    Farzaneh Afkhami

    2013-01-01

    Full Text Available Objective: Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography.Materials and Methods: Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured.Results: Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm.Conclusion: The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions.

  5. Radiographic Localization of the Mental Foramen and Mandibular Canal

    Science.gov (United States)

    Afkhami, Farzaneh; Haraji, Afshin; Boostani, Hamid Reza

    2013-01-01

    Objective: Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography. Materials and Methods: Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured. Results: Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm. Conclusion: The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions. PMID:24910651

  6. Microtensile bond strength between adhesive cements and root canal dentin

    OpenAIRE

    Bouillaguet, Serge; Troesch, Sabra; Wataha, John C.; Krejci, Ivo; Meyer, Jean Marc; Pashley, David H

    2003-01-01

    The hypotheses tested were that the bond strength of adhesive cements to root canal dentin (1) would be reduced as a function of configuration factor, polymerization process and type of luting material and (2) would be lowered near the apex of the tooth.

  7. Lightlike Hypersurfaces and Canal Hypersurfaces of Lorentzian Surfaces

    Directory of Open Access Journals (Sweden)

    Jianguo Sun

    2014-01-01

    Full Text Available The lightlike hypersurfaces in semi-Euclidean space are of special interest in Relativity Theory. In particular, the singularities of these lightlike hypersurfaces provide good models for the study of different horizon types. And we obtain some geometrical propositions of the canal hypersurfaces of Lorentzian surfaces. We introduce the notions of flatness for these hypersurfaces and study their singularities.

  8. Interactions between root canal irrigants, sealers and dentin

    NARCIS (Netherlands)

    Neelakantan, P.

    2016-01-01

    The objective of this thesis was to determine the interactions between root filling materials and root dentin and to investigate if root canal irrigating solutions had an impact on these interactions. The following outcomes were assessed in the studies encompassed in this thesis: (i) dislocation

  9. Independent and Confluent Middle Mesial Root Canals in Mandibular First Molars: A Report of Four Cases

    Directory of Open Access Journals (Sweden)

    Mohanavelu Deepalakshmi

    2012-01-01

    Full Text Available Mandibular molars demonstrate considerable variations with respect to number of roots and root canals. The possibility of additional root canals should be considered even in teeth with a low frequency of abnormal root canal anatomy. This paper discusses the endodontic management of the rare anatomical complexity middle mesial canals in mandibular first molar and also serves to remind the clinicians that such anatomical variations should be taken into account during the endodontic treatment of the mandibular molars.

  10. Closure of the vertebral canal in human embryos and fetuses

    NARCIS (Netherlands)

    Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S. Eleonore; Lamers, Wouter H.

    2017-01-01

    The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10weeks of

  11. 33 CFR 207.100 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware...

    Science.gov (United States)

    2010-07-01

    ... or pass through the waterway. Vessels carrying rods, poles, or other gear extending above the top of the vessel's mast will be required to lower such equipment to a level with the top of the mast before...

  12. Endodontic treatment of two-canalled maxillary central and lateral incisors: a case report

    OpenAIRE

    Shokouhinejad, Noushin; Sheykhrezaee, Mohammad Saeed; Assadian, Hadi

    2009-01-01

    Familiarity with the intricacies and variations of root canal morphology is essential for successful endodontic treatment. Maxillary central and lateral incisors are known to be single-rooted with one canal, however, this case report describes endodontic treatment of maxillary central and lateral incisors with two buccopalatal root canals.

  13. Endodontic treatment of two-canalled maxillary central and lateral incisors: a case report

    Science.gov (United States)

    Shokouhinejad, Noushin; Sheykhrezaee, Mohammad Saeed; Assadian, Hadi

    2009-01-01

    Familiarity with the intricacies and variations of root canal morphology is essential for successful endodontic treatment. Maxillary central and lateral incisors are known to be single-rooted with one canal, however, this case report describes endodontic treatment of maxillary central and lateral incisors with two buccopalatal root canals. PMID:23940491

  14. 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) All vessels intending to transit the Panama Canal, other than vessels of war, must be measured and...

  15. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals

    NARCIS (Netherlands)

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

    2013-01-01

    Aim (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

  16. Endodontic Treatment of a Mandibular Second Premolar with Three Roots and Three Canals

    Directory of Open Access Journals (Sweden)

    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.

  17. Chemical concentrations in water and suspended sediment, Green River to Lower Duwamish Waterway near Seattle, Washington, 2016–17

    Science.gov (United States)

    Conn, Kathleen E.; Black, Robert W.; Peterson, Norman T.; Senter, Craig A.; Chapman, Elena A.

    2018-01-05

    From August 2016 to March 2017, the U.S. Geological Survey (USGS) collected representative samples of filtered and unfiltered water and suspended sediment (including the colloidal fraction) at USGS streamgage 12113390 (Duwamish River at Golf Course, at Tukwila, Washington) during 13 periods of differing flow conditions. Samples were analyzed by Washington-State-accredited laboratories for a large suite of compounds, including metals, dioxins/furans, semivolatile compounds including polycyclic aromatic hydrocarbons, butyltins, the 209 polychlorinated biphenyl (PCB) congeners, and total and dissolved organic carbon. Concurrent with the chemistry sampling, water-quality field parameters were measured, and representative water samples were collected and analyzed for river suspended-sediment concentration and particle-size distribution. The results provide new data that can be used to estimate sediment and chemical loads transported by the Green River to the Lower Duwamish Waterway.

  18. Review of Reports on Lake Erie-Lake Ontario Waterway, New York. Appendix E. Impact Assessment and Environment Plan.

    Science.gov (United States)

    1973-10-01

    Crops The dominant land-use type along most of the prt)psed route ()t the canal is agricultural. A- food chains and nutrient t y les are de- pendent on...space or as a means of flood-plain protection. E-74 .. ... .... . . .. . . . . .. ... .. .I.1 YouNGS TOWN -iR* N LEGENTO BCAMBRIA Devoped Zone

  19. [Canal Finder System 89!!! Improvements and indications after 4 years of experimentation and use].

    Science.gov (United States)

    Lévy, G

    1990-01-01

    Actually, the CANAL FINDER SYSTEM is the only entirely automated endodontic device. After four years of existence, many evaluations were able to show the qualities of this system regarding root canal penetration, cleaning and shaping. The earlier concerns such as ergonomical problems were solved: automated extraction of the K-file, automated sodium hypochlorite irrigation. A new file was created, particularly well adapted to the root canal shaping of curved canals. This addition has improved the efficiency of the automated instrumentation. The CANAL FINDER SYSTEM has reached a maturity level permitting an excellent reliability and ease of use.

  20. Position and course of the mandibular canal in skulls.

    Science.gov (United States)

    Ozturk, Ayla; Potluri, Anitha; Vieira, Alexandre R

    2012-04-01

    The aim of this study was to examine and describe the topography of the mandibular canal (MC) in both vertical and occlusal dimensions. Fifty-two adult skulls deposited in the University of Pittsburgh School of Dental Medicine skull collection were evaluated in this study. Cone-beam computerized tomographic scans of each skull were obtained. The vertical course of MC was classified into 3 types: straight projection (12.2%), catenary-like configuration (51.1%), and progressive descent from posterior to anterior (36.7%). The evaluation of the buccolingual dimension showed that the mandibular canal was located either in contact with or close to the lingual cortical plate (≤ 2 mm) in the molar region of the majority of the cases. As it proceeds anteriorly it moves toward the buccal aspect of the mandible, where it finally emerges through the mental foramen. Three emerging patterns of mandibular canal were observed: sharp turn (53.2%), soft curved exit (28.8%), and straight path (17.4%). The examination of the vertical dimension showed that the canal was located almost 1 cm above the inferior border of the mandible and then ascended to reach the mental foramen, which is located ~16 mm (range 13.4-20.3 mm) above the inferior border of the mandible. We found a strong correlation between height of the mandible and location of the mental foramen (r = 0.64; P mandibular canal described in vertical and axial dimensions and variation in its path have been classified. In addition to variation in location of MC, it has different anatomic configurations which clinicians should be familiar with in any surgical procedures involving the posterior mandible. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Determinants of spatial and temporal coding by semicircular canal afferents.

    Science.gov (United States)

    Highstein, Stephen M; Rabbitt, Richard D; Holstein, Gay R; Boyle, Richard D

    2005-05-01

    The vestibular semicircular canals are internal sensors that signal the magnitude, direction, and temporal properties of angular head motion. Fluid mechanics within the 3-canal labyrinth code the direction of movement and integrate angular acceleration stimuli over time. Directional coding is accomplished by decomposition of complex angular accelerations into 3 biomechanical components-one component exciting each of the 3 ampullary organs and associated afferent nerve bundles separately. For low-frequency angular motion stimuli, fluid displacement within each canal is proportional to angular acceleration. At higher frequencies, above the lower corner frequency, real-time integration is accomplished by viscous forces arising from the movement of fluid within the slender lumen of each canal. This results in angular velocity sensitive fluid displacements. Reflecting this, a subset of afferent fibers indeed report angular acceleration to the brain for low frequencies of head movement and report angular velocity for higher frequencies. However, a substantial number of afferent fibers also report angular acceleration, or a signal between acceleration and velocity, even at frequencies where the endolymph displacement is known to follow angular head velocity. These non-velocity-sensitive afferent signals cannot be attributed to canal biomechanics alone. The responses of non-velocity-sensitive cells include a mathematical differentiation (first-order or fractional) imparted by hair-cell and/or afferent complexes. This mathematical differentiation from velocity to acceleration cannot be attributed to hair cell ionic currents, but occurs as a result of the dynamics of synaptic transmission between hair cells and their primary afferent fibers. The evidence for this conclusion is reviewed below.

  2. Spatial and seasonal variations of the contamination within water body of the Grand Canal, China

    NARCIS (Netherlands)

    Wang, X.L.; Han, Jingyi; Xu, L.G.; Zhang, Q.

    2010-01-01

    To delineate the character of contaminations in the Grand Canal, China, a three-year study (2004-2006) was conducted to investigate variations the water quality in the canal. Results showed that the variation of water quality within the Grand Canal was of there is remarkable spatial and seasonal

  3. IMPACT OF CANAL DESIGN LIMITATIONS ON WATER DELIVERY OPERATIONS AND AUTOMATION

    Science.gov (United States)

    Irrigation canals are often designed for water transmission. The design engineer simply ensures that the canal will pass the maximum design discharge. However, irrigation canals frequently operated far below design capacity. Because demands and the distribution of flow at bifurcations (branch points...

  4. Managing a mandibular second premolar with three-canal and taurodontism: a case report.

    Science.gov (United States)

    Mokhtari, Hadi; Niknami, Mahdi; Zand, Vahid

    2013-01-01

    Root canal anatomy diversity and aberrations are common especially in permanent dentition. A thorough understanding of the basic root canal anatomy and its diversities are necessary for successful endodontic treatment. Mandibular second premolars are usually single-rooted and have one root canal. Incidence of three separate root canals in this tooth is quite rare and taurodontism with three separate canals has never been reported in literature so far. The use of cone-beam computed tomography scan in this rare case greatly contributed to making a confirmatory diagnosis and successful nonsurgical endodontic management thereafter.

  5. Waterborne Commerce of the United States, Calendar Year 1986. Part 3. Waterways and Harbors, Great Lakes

    Science.gov (United States)

    1988-05-31

    Unclassified 22a NAME OF RESPONSIBLE INDVIDUAL 22b TELEPHONE (Include Area Code) 22c. OFFICE SYMBOL David L. Penick (504) 862-1404 CEWRC-NDC-CC DO Form...EA 0) THE LAKE GEORGE ARNCI TO 0.2 S PKEST NOIA nIPLIS 61LV. PROJECT DE’TH: 29 FEET II APPR1AC" C.HANNEL, 20 FElT IN PAROOR bASIN, 27 FEET IN CANAL

  6. 77 FR 27007 - Inland Waterways Navigation Regulations

    Science.gov (United States)

    2012-05-08

    ... waterways navigation regulations. Specifically, this rule proposes to redefine the geographical points which... navigation restrictions on the public and private industry. If you think that your business, organization, or... economic impact on it, please submit a comment (see ADDRESSES) explaining why you think it qualifies and...

  7. Bifid mandibular canal: confirmation of limited cone beam CT findings by gross anatomical and histological investigations

    Science.gov (United States)

    Fukami, K; Shiozaki, K; Mishima, A; Kuribayashi, A; Hamada, Y; Kobayashi, K

    2012-01-01

    Objectives The aims of this study were (1) to assess the validity of limited cone beam CT (CBCT) in detecting the distribution of bifid mandibular canals in the retromolar region by comparing its findings with those of panoramic radiography and spiral CT imaging, and (2) to confirm the contents of such canals depicted on limited CBCT images by using gross anatomical and histological methods. Methods Bilateral bifid mandibular canals of a Japanese cadaver were investigated. The canals depicted on panoramic radiography, spiral CT and limited CBCT images were compared. Cross-sectional limited CBCT images of these canals were compared with gross anatomical sections of the mandible and their contents were confirmed histologically. Results The spiral CT and limited CBCT images showed the bilateral bifid mandibular canals in the retromolar region whereas the panoramic radiographs indicated the presence of only the left bifid mandibular canal. The canal distribution was more distinct in the limited CBCT images than in the spiral CT images and the cross-sectional limited CBCT images were consistent with the gross anatomical sections. Histologically, the canals contained several nerve bundles and arteries among which the largest nerve and artery were of a similar size. Conclusion Limited CBCT is valuable for assessing the distribution of bifid mandibular canals. It is clinically significant to accurately localize a bifid mandibular canal of the retromolar region because it contains a nerve bundle and artery. PMID:22116121

  8. Determining sources of fecal bacteria in waterways.

    Science.gov (United States)

    Yan, Tao; Sadowsky, Michael J

    2007-06-01

    The microbiological contamination of waterways by pathogenic microbes has been, and is still, a persistent public safety concern in the United States and in most countries of the world. As most enteric pathogens are transmitted through the fecal-oral route, fecal pollution is generally regarded as the major contributor of pathogens to waterways. Fecal pollution of waterways can originate from wastewater treatment facilities, septic tanks, domestic- and wild-animal feces, and pets. Because enteric pathogens are derived from human or animal sources, techniques capable of identifying and apportioning fecal sources have been intensively investigated for use in remediation efforts and to satisfy regulatory concerns. Pollution of human origin is of the most concern, since human feces is more likely to contain human-specific enteric pathogens. Fecal indicator bacteria have been used successfully as the primary tool for microbiologically based risk assessment. However measurement of fecal indicator bacteria does not define what pathogens are present, or define the sources of these bacteria. Microbial source tracking (MST) methods that have the ability to differentiate among sources of fecal pollution are currently under development. These methods will ultimately be useful for risk assessment purposes and to aid regulatory agencies in developing strategies to remediate microbiologically impaired waterways.

  9. The width of the incisive canal and labial alveolar bone of the incisive canal: an assessment on CT images

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Yang Gyun; Jang, Hyun Seon; Kim, Byung Ock; Kim, Jin Soo [Chosun Univ. College of Dentistry, Gwangju (Korea, Republic of)

    2006-09-15

    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)

  10. First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

    Directory of Open Access Journals (Sweden)

    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.

  11. A cone-beam computed tomography study of the root canal morphology of mandibular first premolars and the location of root canal orifices and apical foramina in a Chinese subpopulation.

    Science.gov (United States)

    Yang, Haibing; Tian, Cheng; Li, Guoju; Yang, Lin; Han, Xuan; Wang, Yan

    2013-04-01

    Successful root canal treatment is dependent on detailed knowledge of the morphology of the root canal system. The aim of this study was to investigate the morphology of the root canal systems of mandibular first premolars and the location of root canal orifices and apical foramina in a Chinese subpopulation using cone-beam computed tomography scanning. A total of 440 cone-beam computed tomographic images of mandibular first premolars were obtained from 238 patients. Tooth position, root canal morphology, the distance between the apical foramen and the anatomic apex, and the distance between the 2 root canal orifices of mandibular first premolars with 2 root canals were investigated. The Fisher exact test was used to analyze the correlation between the number of root canals and tooth position. Overall, 1.14% (n = 5) of the teeth had a C-shaped root canal system, 77.14% (n = 335) had 1 root canal, and 22.05% (n = 97) had 2 root canals from type II to type V. The remaining 0.68% (n = 3) were classified as type VIII, which had 3 root canals. The most frequent distribution of the distance between the apical foramen and the anatomic apex in 335 mandibular first premolars with 1 root canal was 1-2 mm (n = 192). The distance between the apical foramen and the anatomic apex of mandibular first premolars with 2 root canals was in accord with that of mandibular first premolars with 1 root canal. The distance between the 2 root canal orifices of mandibular first premolars with 2 root canals was approximately 13 mm. Most mandibular first premolars had 1 root canal. More than 1 of 5 mandibular first premolars had complex root canal systems (with 2 or more root canals). This study provides supplemental information about the root canals of mandibular first premolars in a Chinese subpopulation. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. 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.

  13. Dimension, anatomy and morphology of the mesiobuccal root canal system in maxillary molars.

    Science.gov (United States)

    Degerness, Randy A; Bowles, Walter R

    2010-06-01

    To increase our understanding of the root canal system, we examined the mesiobuccal (MB) roots of maxillary first and second molars, which are considered to be one of the most complex root canal systems. Uninstrumented MB roots from 153 teeth were imbedded, sectioned, and observed at 8x using a stereomicroscope for main canal numbers, isthmus presence, and dimensional size of canals and dentin walls. The number of canals observed in maxillary first and second molars was 20% and 38.1% for one canal, 79.8% and 60.3% for two canals, and 1.1% and 1.6% for three canals, respectively. The buccal canal was larger than lingual or middle canals at all levels of the root. The average distance between the two main canals was 1.2 +/- 0.6 mm in first molars and 1.78 +/- 0.6 mm in second molars. Isthmus tissue increased greatly at 3.6 mm from the apex, suggesting optimal root resection at this level. Little differences in thickness between mesial and distal canal walls were seen until reaching the coronal sections of the root where the average canal wall thickness was found to be thinner (33%) on the distal, suggesting a "danger zone" for maxillary molars at a level where the root joins the crown of the tooth. The observations made here provide a more precise understanding of the maxillary MB root system. Orthograde and retrograde root canal therapy might be improved with a comprehensive understanding of pulpal morphology throughout the entire MB root. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Cord Cystic Cavities: Syringomyelia and Prominent Central Canal.

    Science.gov (United States)

    Jones, Blaise V

    2017-04-01

    Syringomyelia is the term given to cystic cavities in the spinal cord, most of which are associated with congenital malformations of the craniocervical junction and represent dilation of the central canal of the cord. As such, syrinxes can be considered analogous to hydrocephalus. The exact etiology of syrinx formation remains a subject of debate, but there is ample evidence that they are the result of obstruction of the normal flow of cerebrospinal fluid between the intracranial and spinal compartments. The chances that a syrinx will progress over time are much greater when they are associated with a causative lesion (Chiari malformation, tumor, infection, and trauma), but asymptomatic central canal dilation may be a stable incidental finding. Although spinal cord neoplasms are a recognized etiology for syrinx formation, especially in adults, it is not always necessary to administer contrast when evaluating a syrinx for the first time with magnetic resonance imaging. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Digging navigable waterways through lagoon tidal flats: which short and long-term impacts on groundwater dynamics and quality?

    Science.gov (United States)

    Teatini, Pietro; Isotton, Giovanni; Nardean, Stefano; Ferronato, Massimiliano; Tosi, Luigi; Da Lio, Cristina; Zaggia, Luca; Bellafiore, Debora; Zecchin, Massimo; Baradello, Luca; Corami, Fabiana; Libralato, Giovanni; Morabito, Elisa; Broglia, Riccardo; Zaghi, Stefano

    2017-04-01

    Coastal lagoons are highly valued ephemeral habitats that have experienced in many cases the pressure of human activities since the development of urbanisation and economic activities within or around their boundaries. One typical intervention is dredging of canals to increase the exchange of water with the sea or for navigation purposes. In order to divert the route of large cruise liners from the historic center of Venice, Italy, the Venice Port Authority has recently proposed a project for the dredging of a new 3-km long and 10-m deep navigation canal (called Marghera-Venice Canal, MVC, in the sequel) through the shallows of the Venice Lagoon. The MVC will connect the passenger terminal located in the southwestern part of the historic center to a main channel that reaches the industrial area on the western lagoon margin. Can the new MVC facilitate saltwater intrusion below the lagoon bottom? Can the release into the lagoon of the chemicals detected in the groundwater around the industrial site be favoured by the MVC excavation? Can the depression waves generated by the ship transit (known as ship-wakes) along the MVC affect the flow and contaminant exchange between the subsurface and surficial systems? A response to these questions has been provided by the use of uncoupled and coupled density-dependent groundwater flow and transport simulators. The hydrogeological modelling has been supported by an in-depth characterization of the Venice lagoon subsurface along the MVC. Geophysical surveys, laboratory analyses on groundwater and sediment samples, in-situ measurements through piezometers and pressure sensors, and the outcome of 3D hydrodynamic and computational fluid dynamic (CFD) models have been used to set-up and calibrate the subsurface multi-model approach. The modelling results can be summarized as follows: i) the MVC has a negligible effect in relation to the propagation of the tidal regime into the subsoil; ii) the depression caused by the ship transit

  16. OCC and state of New York settle Love Canal claims

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    Following a 14-year legal battle, the state of New York and Occidental Chemical Corporation (OCC) have entered into a consent judgement in the Love Canal litigation. The June 21, 1994 judgement, which was approved by the US District Court for the Western District of New York on July 1, 1994, requires that OCC pay the state $98 million in exchange for a release of all state claims remaining against the company.

  17. Usefulness and limitations of neuroradiological examinations in lumbar canal stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Nishi, Shogo; Hanakita, Junya; Suwa, Hideyuki; Ohta, Fumito; Sakaida, Hiroshi (Shizuoka General Hospital (Japan))

    1989-09-01

    Since 1983, we have performed 434 spinal surgery operations. Among them are included 51 cases of lumbar canal stenosis. For these 51 cases, we performed several neuroradiological examinations, such as lumbar plain X-ray, myelography, metrizamide-CT scan (Met-CT) and magnetic resonance imaging (MRI). On myelography, these 51 patients were divided into three types; a complete block type with 29 patients, soy-beans type with 7 patients and strangulation type with 15 patients. Met CT was performed in 37 cases. In both strangulation type and soy-beans type which had been showed through myelography, Met-CT could clearly demonstrate the subarachnoid space, and several structures around the lumbar spinal canal could be clearly identified. In cases which myelography revealed as complete-block type, we identified two subtypes. In the first type subarachnoid space was clearly demonstrated by Met-CT. The second type was comprised of those cases where Met-CT scan could not demonstrate subarachnoid space at all. MRI was performed on 21 patients. MRI clearly showed the anatomical relationship of disc, subarachnoid space, yellow ligament and hypertrophied bony structure. MRI was thus able to bring useful information about lumbar canal stenosis even in cases where Met-CT gave little information due to the lack of metrizamide penetration of the stenotic subarachnoid space. (J.P.N.).

  18. Comparing the Fracture Rate of Hero 642, FlexMaster and Mtwo in the Simulated Canals.

    Science.gov (United States)

    Labaf, Hosein; Haghgoo, Roza; Nazarimoghadam, Kiumars; Mohamadibasir, Mahshid

    2014-01-01

    File fracture is one of the main procedural mishaps in endodontic treatment. The aim of this in vitro study was to compare the fracture rate of three NiTi rotary systems; Hero 642, Mtwo and FlexMaster in artificial canals. In this study, bovine long bone was used. After primary preparation of bones, longitudinal sections with 4-cm diameter were cut and encoded. Subsequently, semicircular sections were prepared. A total number of 500 canals were created in the same way; the upper 3 mm of the canals were initially prepared with orifice shapers and then canals were filed with FlexMaster files sizes 25/0.02 and 25/0.04 to 13 mm of canal length. The prepared canals were assigned into 3 groups of the following systems: Hero 642, Mtwo and FlexMaster. Six selected instruments were used from each system; the files were applied 13 mm along the canals for 10 sec with manufacturer's suggested speed and torque. The number of the canals prepared by each file before its separation was recorded; finally the data was analyzed with ANOVA test. Mean number of prepared canals in Mtwo, FlexMaster and Hero groups before file separation was 15, 25 and 32, respectively. RESULTS of this study showed that the number of prepared canals by Hero 642 was more than FlexMaster and Mtwo systems.

  19. Genetic and life-history trait variation of the amphipod Melita plumulosa from polluted and unpolluted waterways in eastern Australia.

    Science.gov (United States)

    Chung, Pann Pann; Hyne, Ross V; Mann, Reinier M; Ballard, J William O

    2008-09-15

    To monitor genetic diversity and environmental contamination in eastern Australia, toxicity studies have employed the sensitive benthic amphipod Melita plumulosa. The goal of this study was to examine the genetic and life-history variability of natural populations of M. plumulosa from the Parramatta (polluted) and Hawkesbury (unpolluted) Rivers. The underlying genetics of the populations in these distinct waterways was examined at one mitochondrial (cytochrome c oxidase subunit I (COI)) and one nuclear (ribosomal internal transcribed spacer region 1 (ITS1)) locus. Seven unique haplotypes for COI were found amongst animals from the Parramatta River, while animals from the Hawkesbury River showed a complete absence of genetic variation at this locus. At ITS1 a total of two sequence variants were found amongst Parramatta River amphipods and three sequence variants among Hawkesbury River animals, with no common variants across the two river systems. To establish whether genetic differences were associated with organismal responses to toxicant exposure, two life-history trait variables (female head length as an estimator of amphipod size and female fecundity) were analyzed. Life-history trait analyses showed that females from the Hawkesbury River were significantly larger and more fecund. These data have critical implications for toxicity tests, the use of laboratory cultures for testing purposes, and environmental contamination in Sydney Harbor.

  20. Genetic and life-history trait variation of the amphipod Melita plumulosa from polluted and unpolluted waterways in eastern Australia

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Pann Pann [Evolution and Ecology Research Centre, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 2052 (Australia); Hyne, Ross V. [Ecotoxicology and Environmental Contaminants Section, NSW Department of Environment and Climate Change, PO Box 29, Lidcombe, NSW 1825 (Australia); Mann, Reinier M. [Centre for Ecotoxicology, Department of Environmental Sciences, University of Technology-Sydney, C/-PO Box 29, Lidcombe, NSW 1825 (Australia); Ballard, J. William O. [Evolution and Ecology Research Centre, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 2052 (Australia)], E-mail: w.ballard@unsw.edu.au

    2008-09-15

    To monitor genetic diversity and environmental contamination in eastern Australia, toxicity studies have employed the sensitive benthic amphipod Melita plumulosa. The goal of this study was to examine the genetic and life-history variability of natural populations of M. plumulosa from the Parramatta (polluted) and Hawkesbury (unpolluted) Rivers. The underlying genetics of the populations in these distinct waterways was examined at one mitochondrial (cytochrome c oxidase subunit I (COI)) and one nuclear (ribosomal internal transcribed spacer region 1 (ITS1)) locus. Seven unique haplotypes for COI were found amongst animals from the Parramatta River, while animals from the Hawkesbury River showed a complete absence of genetic variation at this locus. At ITS1 a total of two sequence variants were found amongst Parramatta River amphipods and three sequence variants among Hawkesbury River animals, with no common variants across the two river systems. To establish whether genetic differences were associated with organismal responses to toxicant exposure, two life-history trait variables (female head length as an estimator of amphipod size and female fecundity) were analyzed. Life-history trait analyses showed that females from the Hawkesbury River were significantly larger and more fecund. These data have critical implications for toxicity tests, the use of laboratory cultures for testing purposes, and environmental contamination in Sydney Harbor.

  1. Toxicity of harbour canal sediments before dredging and after off shore disposal

    NARCIS (Netherlands)

    Van den Hurk, P.; Eertman, R.H.M.; Stronkhorst, J.

    1997-01-01

    Dredge material from an entrance waterway to the port of Rotterdam and sediments from the North Sea off-shore disposal site were tested for toxicity using three different sediment bioassays, The goals of the study were to evaluate if bioassays generate useful additional information to chemical based

  2. A quantitative analysis of rotary, ultrasonic and manual techniques to treat proximally flattened root canals

    Directory of Open Access Journals (Sweden)

    Fabiana Soares Grecca

    2007-04-01

    Full Text Available OBJECTIVE: The efficiency of rotary, manual and ultrasonic root canal instrumentation techniques was investigated in proximally flattened root canals. MATERIAL AND METHODS: Forty human mandibular left and right central incisors, lateral incisors and premolars were used. The pulp tissue was removed and the root canals were filled with red die. Teeth were instrumented using three techniques: (i K3 and ProTaper rotary systems; (ii ultrasonic crown-down technique; and (iii progressive manual technique. Roots were bisected longitudinally in a buccolingual direction. The instrumented canal walls were digitally captured and the images obtained were analyzed using the Sigma Scan software. Canal walls were evaluated for total canal wall area versus non-instrumented area on which dye remained. RESULTS: No statistically significant difference was found between the instrumentation techniques studied (p<0.05. CONCLUSION: The findings of this study showed that no instrumentation technique was 100% efficient to remove the dye.

  3. Pesticide Reduction Campaign: Greener Pesticides for Cleaner Waterways

    Science.gov (United States)

    Information about the SFBWQP Greener Pesticides for Cleaner Waterways project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  4. Second mesiobuccal canal detection in maxillary first molars using microscopy and ultrasonics.

    Science.gov (United States)

    Alaçam, Tayfun; Tinaz, Ali Cemal; Genç, Ozgür; Kayaoglu, Guven

    2008-12-01

    The aim of this study was to investigate whether the use of operating microscope in combination with ultrasonics increased the rate of second mesiobuccal (MB2) canal detection in permanent maxillary first molar teeth. A hundred extracted human maxillary first molars were assessed. After location of the main canals, the MB2 canal was sought in all teeth first without microscopy, then with the aid of the operating microscope and finally with the combined use of the operating microscope and ultrasonics. With these techniques, the MB2 canal was detected in 62%, 67% and 74% of the teeth, respectively. The combination of the operating microscope and ultrasonics detected significantly more MB2 canals than when no microscopy was utilized (P ultrasonics increased the detection of MB2 canals in maxillary first permanent molars.

  5. A clinical and radiographic study of four different root canal fillings in primary molars

    OpenAIRE

    Alaa O Al-Ostwani; Bashier M Al-Monaqel; Mohamed K Al-Tinawi

    2016-01-01

    Background: Successful treatment of infected primary teeth aims to preserve the child′s health. However, the complex morphology of primary root canals and the desire for shorter therapy sessions put the necessity to search for the ideal root canal paste. Aims: To evaluate pulpectomy of nonvital primary molars using four different root canal filling pastes zinc oxide and propolis (ZOP) as a new paste, endoflas-chlorophenol-free as a new paste free of chlorophenol, metapex paste, and zinc oxide...

  6. A study of mandibular foramen and mandibular canal using orthopantomograms

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hee Sang; Kim, Jhai Dhuck [Department of Dentistry, Graduate School, Chosun University, Kwangju (Korea, Republic of)

    1983-11-15

    The mandibular canal must be considered carefully during surgical treatment, especially surgical extraction of the impacted tooth and intraosseous implant because it contains the important inferior alveolar nerve and vessel. Th e author investigated the curvature of the mandibular canal, the positional frequency of mandibular foramen to the occlusal plane and gonial angle and the positional frequency of the mental foramen to the tooth site using orthopantomorgrams. The materials considered of 295 orthopantomograms divided into seven groups ranging from the first decade to 6th decade. The results were as follows: 1. The position of mandibular foramen was most frequently below occlusal plane in Group I (78.6%) and Group II (71.2%) , above occlusal plane in Group III (63.0%), Group IV (71.1%), Group V (57.6%), Group VI (76.7%) and Group VII (70.0%). 2. The curvature of mandibular canal was 142.82 .deg. in Group I, 142.09 .deg. in Group II, 139.34 .deg. in Group III, 141.48 .deg. in Group IV, 138.45 .deg. in Group V, 140.77 .deg. in Group VI and 143.89 .deg. in Group VII. 3. The gonial angle was 125.82 .deg. in Group I, 123.18 .deg. in Group II, 124.06 .deg. in Group III, 120.45 .deg. in Group IV, 121.12 .deg. in Group V, 121.63 .deg. in Group VI and 121.24 .deg. in Group VII. 4. The position of the mental foramen was most frequently below the apex of mandibular first premolar in Group I (57.2%), between the apex of mandibular first and second premolar in Group II (59.6%) and Group III (48.9%), and below the apex of mandibular second premolar in Group IV (39.2%), Group V (48.5%) Group VI (46.7%) and Group VII (56.4%).

  7. Investigations into in situ Enterococcus faecalis biofilm removal by passive and active sodium hypochlorite irrigation delivered into the lateral canal of a simulated root canal model.

    Science.gov (United States)

    Mohmmed, S A; Vianna, M E; Penny, M R; Hilton, S T; Mordan, N J; Knowles, J C

    2017-11-27

    To investigate in situ Enterococcus faecalis biofilm removal from the lateral canal of a simulated root canal system using passive or active irrigation protocols. Root canal models (n = 43) were manufactured from transparent resin materials using 3D-printing. Each canal was created with an 18 mm length, apical size 30, a .06 taper, and a lateral canal of 3 mm length, 0.3 mm diameter. Biofilms were grown on the lateral canal and apical 3 mm of the main canal for 10 days. Biofilm of three models was examined using SEM. The other forty models were divided to four groups (n = 10). The models were observed under a fluorescence microscope. Following 60 s of 9 mL of 2.5% NaOCl irrigation using syringe and needle, the irrigant was either left stagnant in the canal or activated using gutta-percha, sonic or ultrasonic methods for 30 s. Images were then captured every second using an external camera. The residual biofilm percentages were measured using image analysis software. The data were analyzed using generalized linear mixed models. A significance level of 0.05 was used throughout. The greatest level of biofilm removal was with ultrasonic agitation (66.76%) followed by sonic (45.49%), manual agitation (43.97%), and passive irrigation groups (38.67%) respectively. The differences were significant between the residual biofilm in the passive irrigation and both sonic & ultrasonic groups (P = 0.001). Agitation resulted in better penetration of the 2.5% NaOCl into the lateral canal of an artificial root canal model. Ultrasonic agitation of NaOCl improved the removal of biofilm. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. Radiographic evaluation of the course and visibility of the mandibular canal

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yun Hoa; Cho, Bong Hae [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Pusan National University, Yangsan (Korea, Republic of)

    2014-12-15

    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.

  9. Management of the Nasopalatine Canal and Foramen Associated With Dental Implant Therapy.

    Science.gov (United States)

    Cavallaro, John; Tsuji, Shota; Chiu, Tzu-Shan; Greenstein, Gary

    2016-06-01

    In some patients, the contents of the nasopalatine canal must be removed to facilitate placement of a dental implant into the canal. Reasons to enucleate the canal in preparation for a bone graft or a dental implant include inadvertent perforation into the canal when creating an osteotomy for an implant, severe atrophy of the maxilla, and a large foramen that precludes placing an implant into the desired location along the bony ridge. The authors searched the dental literature for clinical reports in humans that addressed placement of dental implants into or adjacent to the nasopalatine canal. They found that the nasopalatine canal is usually around 10-mm long and 4-mm wide and slants from the horizontal plane at a 66-degree angle, and there is considerable variation regarding these measurements. Several clinical reports demonstrate that the canal can be enucleated and bone grafted before successful implant placement. It is also possible to place an implant into the canal at the time of surgery and this procedure may or may not be combined with an adjunctive bone graft. Numerous case reports indicate there is usually no permanent loss of sensation of the anterior palate when an implant is placed into the nasopalatine canal. The authors concluded that placing an implant into the nasopalatine canal is a viable procedure as part of a surgical and prosthetic treatment plan when there is a dearth of alternate sites for implant placement. In patients with severe atrophy of the maxilla, combination syndrome, or who have a large or malpositioned nasopalatine canal, the canal can be used as a site to place a dental implant to support a fixed or removable dental prosthesis.

  10. Charlemagne's summit canal: an early medieval hydro-engineering project for passing the Central European Watershed.

    Directory of Open Access Journals (Sweden)

    Christoph Zielhofer

    Full Text Available The Central European Watershed divides the Rhine-Main catchment and the Danube catchment. In the Early Medieval period, when ships were important means of transportation, Charlemagne decided to link both catchments by the construction of a canal connecting the Schwabian Rezat and the Altmühl rivers. The artificial waterway would provide a continuous inland navigation route from the North Sea to the Black Sea. The shortcut is known as Fossa Carolina and represents one of the most important Early Medieval engineering achievements in Europe. Despite the important geostrategic relevance of the construction it is not clarified whether the canal was actually used as a navigation waterway. We present new geophysical data and in situ findings from the trench fills that prove for the first time a total length of the constructed Carolingian canal of at least 2300 metres. We have evidence for a conceptual width of the artificial water course between 5 and 6 metres and a water depth of at least 60 to 80 cm. This allows a crossing way passage of Carolingian cargo scows with a payload of several tons. There is strong evidence for clayey to silty layers in the trench fills which reveal suspension load limited stillwater deposition and, therefore, the evidence of former Carolingian and post-Carolingian ponds. These findings are strongly supported by numerous sapropel layers within the trench fills. Our results presented in this study indicate an extraordinarily advanced construction level of the known course of the canal. Here, the excavated levels of Carolingian trench bottoms were generally sufficient for the efficient construction of stepped ponds and prove a final concept for a summit canal. We have evidence for the artificial Carolingian dislocation of the watershed and assume a sophisticated Early Medieval hydrological engineering concept for supplying the summit of the canal with adequate water.

  11. Effects of irrigation solutions and Calcium hydroxide dressing on root canal treatments of periapical lesions

    Directory of Open Access Journals (Sweden)

    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.

  12. Evaluation of Morphology and Anatomical Measurement of Nasopalatine Canal Using Cone Beam Computed Tomography

    Directory of Open Access Journals (Sweden)

    Mehrdad Panjnoush

    2016-11-01

    Full Text Available Objectives: Precise radiographic assessment of the nasopalatine canal is required to prevent implant failure. The purpose of the current study was to determine the three dimensional (3D morphology, as well as the dimensions of the nasopalatine canal using cone beam computed tomography (CBCT.Materials and Methods: In this descriptive cross-sectional study, maxillary CBCT images from 300 patients (150 men, 150 women were retrospectively evaluated. Sagittal and coronal views were reviewed to determine the nasopalatine canal morphology and dimensions. The difference in canal dimensions between men and women was evaluated using the Student’s t-test while the difference in canal morphology between the two sexes was assessed using Chi-square test.Results: A total of 199 (66.3% patients had type A canal (cylindrical without a branch, 69 (23% had type B canal (a canal with a branch in the upper part, and 32 (10.7 % had type C canal (a canal with a branch in the middle part. Incisive foramen diameter was 4.7±1.11mm on the sagittal section. Alveolar bone width in the anterior part of the canal was 12.3±1.7mm in the upper one third, 10.7±1.7mm in the middle one third, and 9.8±1.4mm in the lower one third. The angle of canal with palate was 109.5±5.7°. On the coronal sections, canal length was 14.1±3.0mm, incisive foramen diameter was 4.6±1.0mm, and canal diameter in the nasal floor was 5.1±1.0mm.                          Conclusions: Significant differences in canal morphology were observed among the patients and CBCT was useful in determining nasopalatine canal morphology and its dimensions before implant placement.Keywords: Anatomy; Cone-Beam Computed Tomography; Dental Implants; Maxilla

  13. Comparison of in situ and in vitro baiting assays for Phytophthora ramorum survey of waterways in the southeastern United States

    Science.gov (United States)

    Steven Oak; Jaesoon Hwang; Steven Jeffers

    2013-01-01

    In situ baiting with whole, intact leaves of Rhododendron spp. has been employed since 2006 by the National Phytophthora ramorum Early Detection survey of forests (national survey). Using this method, P. ramorum was detected for the first time in national survey waterways draining 12 infested ornamental...

  14. 75 FR 30753 - Regulated Navigation Area; Thea Foss and Wheeler-Osgood Waterways EPA Superfund Cleanup Site...

    Science.gov (United States)

    2010-06-02

    ... Waterways EPA Superfund Cleanup Site, Commencement Bay, Tacoma, WA AGENCY: Coast Guard, DHS. ACTION...) Commencement Bay Nearshore/Tideflats superfund cleanup remediation efforts. To more effectively protect those... ] Superfund Cleanup Site, Commencement Bay, Tacoma, WA'' in the Federal Register (73 FR 162, Aug. 20, 2008...

  15. Predicting the postmortem submersion interval for human remains recovered from U.K. waterways.

    Science.gov (United States)

    Heaton, Vivienne; Lagden, Abigail; Moffatt, Colin; Simmons, Tal

    2010-03-01

    This article aims to increase accuracy in estimating the postmortem submersion interval (PMSI) for bodies recovered from rivers in the United Kingdom. Data were collected from closed case files, crime scene reports, and autopsy files concerning bodies recovered over a 15-year period from the River Clyde, Scotland, and the River Mersey and canals in northwest England. One hundred and eighty-seven cases met the study criteria and were scored by quantifying the overall amount of decomposition observed in each case. Statistical analysis showed that the duration of a body's submergence in water and the temperatures to which it was exposed, as measured in accumulated degree days (ADD), had a significant effect on the decay process. Further analysis indicated that there were no significant differences in decomposition between the waterways. By combining the data from all study samples, it was possible to produce a single linear regression model for predicting ADD from observed decomposition.

  16. Configuration and corticalization of the mandibular bifid canal in a Taiwanese adult population: a computed tomography study.

    Science.gov (United States)

    Shen, E-Chin; Fu, Earl; Fu, Martin Ming-Jen; Peng, Michelle

    2014-01-01

    The configuration and degree of corticalization of bifid mandibular canals were examined using medical computed tomography (CT) images from 170 hemimandibles obtained from 308 Taiwanese adults. The configurations of the bifid canals were assessed according to their anatomical position in relation to the ramus, molars, premolars, and mental foramen; their course (anterior/posterior or superior/inferior); the presence or absence of confluence with the main mandibular canal; and the presence or absence of penetration through the mandible to form an accessory foramen. The percentage of the canal length that was corticalized was measured. Two different classifications of bifid canals were also briefly summarized and compared. When bifid canals are present (41.2% of patients; 27.6% of hemimandibles), the bifid canals were primarily located in the ramus and retromolar regions (67.7%) running anteriorly (95.9%) and superiorly (95.9%) without confluence with the main mandibular canal (91.1%). Up to 16.5% of bifid canals form accessory foramina on the cortical surface of the mandible. Approximately 78% of the bifid canals have varied degrees of corticalization around the bifid canals. The configuration and course of 170 mandibular bifid canals were evaluated with CT images. The bifid canals were primarily located in the ramus and retromolar regions; however, 32.4% of the bifid canals were located in potential positions for dental implant placement. Most of the bifid canals ran anteriorly superior to the main mandibular canal, did not rejoin with the main mandibular canal, and diminished within the mandibular body. Approximately half of the bifid canals (45%) were completely corticated.

  17. Comparative scanning electron microscopy evaluation of Canal Brushing technique, sonic activation, and master apical file for the removal of triple antibiotic paste from root canal (in vitro study

    Directory of Open Access Journals (Sweden)

    Deepa Ashoksingh Thakur

    2015-01-01

    Full Text Available Aims: To compare and evaluate the effectiveness of Canal Brushing technique, sonic activation, and master apical file (MAF for the removal of triple antibiotic paste (TAP from root canal using scanning electron microscopy (SEM. Materials and Methods: Twenty-two single rooted teeth were instrumented with ProTaper up to the size number F2 and dressed with TAP. TAP was removed with Canal Brush technique (Group I, n: 6, sonic (EndoActivator (Group II, n: 6, and MAF (Group III, n: 6. Four teeth served as positive (n: 2 and negative (n: 2 controls. The roots were split in the buccolingual direction and prepared for SEM examination (×1000 at coronal, middle, and apical third. Three examiners evaluated the wall cleanliness. Statistical Analysis: Statistical analysis was performed by Kruskal–Wallis test and Wilcoxon rank sum test. Results: Difference in cleanliness between three groups is statistically significant in cervical region only. Pairwise comparison in cervical region Canal Brush and sonic activation showed more removal of TAP than MAF. Conclusions: Canal Brush and sonic activation system showed better result than MAF in the cervical and middle third of canal. In the apical third, none of the techniques showed a better result. None of the techniques showed complete removal of TAP from the canal.

  18. Marginal effects of rural roads and irrigation canals on woody and ...

    African Journals Online (AJOL)

    Plant species richness at the edge of rural road with irrigation canal (37 species) was more than the edge of rural road without irrigation canal (17 species), but the cover value was similar to each other. Punica granatum L. was the most frequent species (more than 80%) on both side of rural road (transect 2 and 3) without ...

  19. Marginal effects of rural roads and irrigation canals on woody and ...

    African Journals Online (AJOL)

    In this study, the presence of different plant species was recorded in ninety 1´1 m plots on nine 100 m transects at the edge of terrene rural roads with irrigation canal and without irrigation canal. Thirty seven plant species were identified in the 9 transects surveyed. Twenty six (70.3%) of those species occurred near the ...

  20. The association between root canal filling and treatment outcome.

    Science.gov (United States)

    Almohareb, Rahaf; Ahlquist, Michael; Englund, Gunilla Sandborgh

    2016-01-01

    The aim of the study was to evaluate the technical quality of endodontic treatment per- formed by postgraduate students in Karolinska Institutet, Stockholm, Sweden during the years (2008-2011) and to evaluate the treatment outcome. In addition, possible influencing factors to treatment outcome were analyzed. All maxillary first molars that received endo- dontic treatment between 2008 and 2011 were included in the study. Pre, post and follow up radiographs were collected.The apical status (PAI-score),the quality of the root canal treat- ment (RCT) and the treatment outcome were assessed. Analysis of the treatment outcome in relation to the quality of root canal treatment and other possible influencing variables was performed by Chi2 or Fisher's Exact test, and the statistical significance was set at Plength. In total, the treatment outcome was successful in 59 (81 %) of the cases. The success rate was 88% in cases with high quality root fillings, compared to 71% in cases with less good quality.There was a non- significant trend (P =0.066) of an association between RCT quality and treatment outcome. In conclusion the association between the quality of the root filling and the treatment outcome was not verified with statistical significance, but the results indicate a trend that satisfactory root fillings are associated with a favorable outcome.This study was limited by its retrospective nature and a relatively small sample size.

  1. Cholera, canals, and contagion: Rediscovering Dr. Beck's report.

    Science.gov (United States)

    Tuite, Ashleigh R; Chan, Christina H; Fisman, David N

    2011-08-01

    Cholera first appeared in North America (in Montreal and Quebec) in 1832 and spread rapidly across the eastern half of the continent. The dispatch of American disease control experts to Lower Canada in anticipation of cholera's spread implies that medical professionals expected spread, possibly from contagion, even though the notion that cholera was contagious was disparaged in medical writings of the time, and would be until John Snow's landmark work in London in the 1850s. Snow's insights derived largely from his observations on spatial and temporal patterns of cholera cases. We discuss a document from the 1832 epidemic, the report of Dr. Lewis Beck to New York's Governor Throop, which anticipates Snow in presenting geospatial data that imply cholera's contagiousness. Beck shows that the movements of immigrants along the newly completed New York state canal system resulted in sequential cholera outbreaks along the canal's path. Although aware of the degree to which this suggested contagion, Beck argues strenuously against the contagiousness of cholera. We explore the social context of early nineteenth-century medicine that probably led Beck to disbelieve his own observations, and to favor a medical model inconsistent with his data. Themes that emerge from our inquiry include belief in disease as a physical manifestation of defective morality, stigmatization of the poor and immigrant groups, and reluctance to overturn prevailing medical models that themselves reflected the economic position of medical practitioners. We show that these themes continue to serve as obstacles to innovation in medical and public health practice today.

  2. Simulation of hypothetical Asian carp egg and larvae development and transport in the Lockport, Brandon Road, Dresden Island, and Marseilles Pools of the Illinois Waterway by use of the Fluvial Egg Drift Simulator (FluEgg) model

    Science.gov (United States)

    Murphy, Elizabeth A.; Garcia, Tatiana; Jackson, P. Ryan; Duncker, James J.

    2016-04-05

    As part of the Great Lakes and Mississippi River Interbasin Study, the U.S. Army Corps of Engineers (USACE) is conducting an assessment of the vulnerability of the Chicago Area Waterway System and Des Plaines River to Asian carp (specifically, Hypophthalmichthys nobilis (bighead carp) and Hypophthalmichthys molitrix (silver carp)) spawning and recruitment. As part of this assessment, the USACE requested the help of the U.S. Geological Survey in predicting the fate and transport of Asian carp eggs hypothetically spawned at the electric dispersal barrier on the Chicago Sanitary and Ship Canal and downstream of the Brandon Road Lock and Dam on the Des Plaines River under dry weather flow and high water temperature conditions. The Fluvial Egg Drift Simulator (FluEgg) model predicted that approximately 80 percent of silver carp eggs spawned near the electric dispersal barrier would hatch within the Lockport and Brandon Road pools (as close as 3.6 miles downstream of the barrier) and approximately 82 percent of the silver carp eggs spawned near the Brandon Road Dam would hatch in the Des Plaines River (as close as 1.6 miles downstream from the gates of Brandon Road Lock). Extension of the FluEgg model to include the fate and transport of larvae until gas bladder inflation—the point at which the larvae begin to leave the drift—suggests that eggs spawned at the electric dispersal barrier would reach the gas bladder inflation stage primarily within the Dresden Island Pool, and those spawned at the Brandon Road Dam would reach this stage primarily within the Marseilles and Starved Rock Pools.

  3. Morphology and ontogeny of multiple lateral-line canals in the rock prickleback, Xiphister mucosus (Cottiformes: Zoarcoidei: Stichaeidae).

    Science.gov (United States)

    Clardy, Todd R; Hilton, Eric J; Vogelbein, Wolfgang K

    2015-10-01

    The structure and ontogeny of lateral-line canals in the Rock Prickleback, Xiphister mucosus, were studied using cleared-and-stained specimens, and the distribution and morphology of neuromasts within lateral-line canals were examined using histology. X. mucosus has seven cephalic canals in a pattern that, aside from four branches of the infraorbital canals, is similar to that of most teleostean fishes. Unlike most other teleosts, however, X. mucosus features multiple trunk lateral-line canals. These include a short median posterior extension of the supratemporal canal and three paired, branching canals located on the dorsolateral, mediolateral, and ventrolateral surfaces. The ventrolateral canal (VLC) includes a loop across the ventral surface of the abdomen. All trunk canals, as well as the branches of the infraorbitals, are supported by small, dermal, ring-like ossifications that develop independently from scales. Trunk canals develop asynchronously with the mediodorsal and dorsolateral canals (DLC) developing earliest, followed by the VLC, and, finally, by the mediolateral canal (MLC). Only the mediodorsal and DLC connect to the cephalic sensory canals. Fractal analysis shows that the complexity of the trunk lateral-line canals stabilizes when all trunk canals develop and begin to branch. Histological sections show that neuromasts are present in all cephalic canals and in the DLC and MLC of the trunk. However, no neuromasts were identified in the VLC or its abdominal loop. The VLC cannot, therefore, directly function as a part of the mechanosensory system in X. mucosus. The evolution and functional role of multiple lateral-line canals are discussed. © 2015 Wiley Periodicals, Inc.

  4. Development of goose- and duck-specific DNA markers to determine sources of Escherichia coli in waterways.

    Science.gov (United States)

    Hamilton, Matthew J; Yan, Tao; Sadowsky, Michael J

    2006-06-01

    The contamination of waterways with fecal material is a persistent threat to public health. Identification of the sources of fecal contamination is a vital component for abatement strategies and for determination of total maximum daily loads. While phenotypic and genotypic techniques have been used to determine potential sources of fecal bacteria in surface waters, most methods require construction of large known-source libraries, and they often fail to adequately differentiate among environmental isolates originating from different animal sources. In this study, we used pooled genomic tester and driver DNAs in suppression subtractive hybridizations to enrich for host source-specific DNA markers for Escherichia coli originating from locally isolated geese. Seven markers were identified. When used as probes in colony hybridization studies, the combined marker DNAs identified 76% of the goose isolates tested and cross-hybridized, on average, with 5% of the human E. coli strains and with less than 10% of the strains obtained from other animal hosts. In addition, the combined probes identified 73% of the duck isolates examined, suggesting that they may be useful for determining the contribution of waterfowl to fecal contamination. However, the hybridization probes reacted mainly with E. coli isolates obtained from geese in the upper midwestern United States, indicating that there is regional specificity of the markers identified. Coupled with high-throughput, automated macro- and microarray screening, these markers may provide a quantitative, cost-effective, and accurate library-independent method for determining the sources of genetically diverse E. coli strains for use in source-tracking studies. However, future efforts to generate DNA markers specific for E. coli must include isolates obtained from geographically diverse animal hosts.

  5. Influence of root canal instrumentation and obturation techniques on intra-operative pain during endodontic therapy.

    Science.gov (United States)

    Martín-González, Jenifer; Echevarría-Pérez, Marta; Sánchez-Domínguez, Benito; Tarilonte-Delgado, Maria-Luisa; Castellanos-Cosano, Lizett; López-Frías, Francisco-Javier; Segura-Egea, Juan-Jose

    2012-09-01

    To analyse the influence of root canal instrumentation and obturation techniques on intra-operative pain experienced by patients during endodontic therapy. A descriptive cross-sectional study was carried out in Ponferrada and Sevilla, Spain, including 80 patients (46 men and 34 women), with ages ranged from 10 to 74 years, randomly recruited. Patient gender and age, affected tooth, pulpal diagnosis, periapical status, previous NSAID or antibiotic (AB) treatment, and root canal instrumentation and obturation techniques were recorded. After root canal treatment (RCT), patients completed a 10-cm visual analogue scale (VAS) that ranked the level of pain. Results were analysed statistically using the Chi-square and ANOVA tests and logistic regression analysis. The mean pain level during root canal treatment was 2.9±3.0 (median=2) in a VAS between 0 and 10. Forty percent of patients experienced no pain. Gender, age, arch, previous NSAIDs or AB treatment and anaesthetic type did not influence significantly the pain level (p>0.05). Pain during root canal treatment was significantly greater in molar teeth (OR=10.1; 95% C.I.=1.6-63.5; p=0.013). Root canal instrumentation and obturation techniques did not affect significantly patients' pain during root canal treatment (p>0.05). Patients feel more pain when RCT is carried out on molar teeth. The root canal instrumentation and obturation techniques do not affect significantly the patients' pain during RCT.

  6. Comparison of shaping ability of RaCe and Hero Shaper instruments in simulated curved canals.

    Science.gov (United States)

    Aydin, Cumhur; Inan, Ugur; Yasar, Senay; Bulucu, Bilinc; Tunca, Yasar M

    2008-03-01

    This study compared the shaping ability of Hero Shaper and RaCe instruments in simulated curved canals. Forty simulated canals in resin blocks were divided into 2 experimental groups, each comprising 20 resin blocks, and prepared with Hero Shaper and RaCe using the crown-down technique. Preoperative and postoperative photographs, recorded using a digital camera, were superimposed and aberrations were recorded. Material removal was measured at 10 points beginning 1 mm from the end point of the canal. Mean total widths, outer and inner width measurements, were determined on each central canal path and differences were statistically analyzed using Student t test. The Hero Shaper and RaCe instruments removed almost the same amount of material from the inner side of the simulated canals. On the outer canal wall, the RaCe instruments removed significantly more material from the first 3 mm (P Hero Shaper removed more material from the middle and coronal aspects of the canal and the differences were statistically significant (P Hero Shaper removed more material from the middle and coronal thirds on the outer canal wall. Hero Shaper instruments showed better centering ability and fewer aberrations. No instrument fractures but some deformations were observed for both systems.

  7. The impact of the New Panama Canal Locks on Texas ports and the Texas economy.

    Science.gov (United States)

    2017-10-01

    This report examines the first year transits through the new Panama Canal locks and its impact on Texas deep water ports. It finds that the canal is operating efficiently and can accommodate 14,000 TEU containerships and bulk vessels up to 125,000 to...

  8. Microorganism penetration in dentinal tubules of instrumented and retreated root canal walls. In vitro SEM study

    Directory of Open Access Journals (Sweden)

    Saad Al-Nazhan

    2014-11-01

    Full Text Available Objectives This in vitro study aimed to investigate the ability of Candida albicans (C. albicans and Enterococcus faecalis (E. faecalis to penetrate dentinal tubules of instrumented and retreated root canal surface of split human teeth. Materials and Methods Sixty intact extracted human single-rooted teeth were divided into 4 groups, negative control, positive control without canal instrumentation, instrumented, and retreated. Root canals in the instrumented group were enlarged with endodontic instruments, while root canals in the retreated group were enlarged, filled, and then removed the canal filling materials. The teeth were split longitudinally after canal preparation in 3 groups except the negative control group. The teeth were inoculated with both microorganisms separately and in combination. Teeth specimens were examined by scanning electron microscopy (SEM, and the depth of penetration into the dentinal tubules was assessed using the SMILE view software (JEOL Ltd. Results Penetration of C. albicans and E. faecalis into the dentinal tubules was observed in all 3 groups, although penetration was partially restricted by dentin debris of tubules in the instrumented group and remnants of canal filling materials in the retreated group. In all 3 groups, E. faecalis penetrated deeper into the dentinal tubules by way of cell division than C. albicans which built colonies and penetrated by means of hyphae. Conclusions Microorganisms can easily penetrate dentinal tubules of root canals with different appearance based on the microorganism size and status of dentinal tubules.

  9. 78 FR 24697 - Inland Waterways Navigation Regulations

    Science.gov (United States)

    2013-04-26

    ... SECURITY Coast Guard 33 CFR Part 162 RIN 1625-AB84 Inland Waterways Navigation Regulations AGENCY: Coast... Navigation (water), Waterways. For the reasons discussed in the preamble, the Coast Guard proposes to amend 33 CFR part 162 as follows: PART 162--INLAND WATERWAYS NAVIGATION REGULATIONS 0 1. The authority...

  10. Evaluation of location and dimensions of mandibular lingual canals: a cone beam computed tomography study.

    Science.gov (United States)

    Wang, Y-M; Ju, Y-R; Pan, W-L; Chan, C-P

    2015-09-01

    This retrospective study evaluated the presence, location, and diameter of the mandibular lingual canals in a Taiwanese population using cone beam computed tomography (CBCT), to help improve the safety of mandibular surgical procedures. A total of 101 patients (46 men and 55 women), with a mean age of 55 years, were enrolled. Cross-sectional CBCT images of the mandible were used to define the orifice and diameter of each lingual canal detected. The relevance of all data for both sexes was assessed and analyzed statistically using non-paired t-tests. The canals were categorized as median (MLC) and lateral lingual canals (LLC) based on the position of the mandible. The midline of the symphysis showed the highest frequency of lingual canals (97.0%), and all patients exhibited at least one lingual perforating bone canal in the mandible. The lingual canal diameter ranged from 0.25 to 1.90 mm (mean 0.61 mm) in the midline region and from 0.25 to 1.60mm (mean 0.58 mm) in the lateral region. Significant differences in diameter were observed between the sexes in the MLC and LLC groups (men>women). The results suggest that mandibular lingual vascular canals are common and detected regularly using CBCT. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  11. [Dentascan computed tomography of the mandibular incisive canal. Its radiologic anatomy and the therapeutic implications].

    Science.gov (United States)

    Calgaro, A; Bison, L; Bellis, G B; Pozzi Mucelli, R

    1999-11-01

    To stress the importance of CT depiction of the mandibular incisive canal. This anatomical structure contains a major neurovascular bundle and is thus very important in the planning of mandibular implants in the canine-incisive area. January through December 1998, sixty patients unselected by age and gender were submitted to mandibular CT. Axial slices were acquired with 1-1.5 mm thickness and 1 mm table feed, and the images were then reformatted with a dedicated dental software. Both the conventional and the Helical techniques were used. The incisive canal appears on Dentascan transverse reconstructions as a round low-density area within mandibular trabecular bone, which is surrounded by a higher-density rim representing the canal walls. This anatomical structure originates from the mental foramen and continues mesially to the mental symphysis. The mandibular canal was visualized in 95% of cases bilaterally (57/60); the incisive canal was depicted on the left side in 41.6% of cases (25/60) and on the right side in 51.6% (31/60). The importance of careful assessment of the mandibular canal course before implantology is now widely recognized. The same holds true for the canine-incisive region in the jaw, to detect the incisive canal if present and prevent any complications from its accidental damage. CT with a dedicated software showed the incisive canal in a large number of patients, which calls for precise reporting of its presence, course, and relationships with teeth.

  12. Effects of Self-Adjusting File, Mtwo, and ProTaper on the root canal wall

    NARCIS (Netherlands)

    Hin, E.S.; Wu, M.K.; Wesselink, P.R.; Shemesh, H.

    2013-01-01

    Introduction The purpose of this ex vivo study was to observe the incidence of cracks in root dentin after root canal preparation with hand files, self-adjusting file (SAF), ProTaper, and Mtwo. Methods One hundred extracted mandibular premolars with single canals were randomly selected. Two

  13. Challenges in fitting a hearing aid to a severely collapsed ear canal and mixed hearing loss.

    Science.gov (United States)

    Oeding, Kristi; Valente, Michael; Chole, Richard

    2012-04-01

    Collapsed ear canals typically occur when an outside force, such as a headset for audiometric testing, is present. However, when a collapsed ear canal occurs without external pressure, this creates a challenge not only for performing audiometric testing but also for coupling a hearing aid to the ear canal. This case report highlights the challenges associated with fitting a hearing aid on a patient with a severe anterior-posterior collapsed ear canal with a mixed hearing loss. A 67-yr-old female originally presented to Washington University in St. Louis School of Medicine in 1996 with a long-standing history of bilateral otosclerosis. She had chronic ear infections in the right ear and a severely collapsed ear canal in the left ear and was fit with a bone anchored hearing aid (BAHA®) on the right side in 2003. However, benefit from the BAHA started to decrease due to changes in hearing, and a different hearing solution was needed. It was proposed that a hearing aid be fit to her collapsed left ear canal; however, trying to couple a hearing aid to the collapsed ear canal required unique noncustom earmold solutions. This case study highlights some of the obstacles and potential solutions for coupling a hearing aid to a severely collapsed ear canal. American Academy of Audiology.

  14. Disinfection of the root canal by sonic, ultrasonic and laser-activated irrigation

    NARCIS (Netherlands)

    van der Sluis, L.W.M.; Verhaagen, B.; Macedo, R.; Versluis, Andreas Michel; Cohenca, N.

    2014-01-01

    Irrigants are chemically inactivated after their reaction with the biofilm and therefore need to be mixed with fresh irrigants. Insight in the flow of the irrigant during a root canal treatment is crucial to understand the importance of the disinfection of the root canal system. This chapter

  15. Microscope magnification and ultrasonic precision guidance for location and negotiation of second mesiobuccal canal: An in vivo study.

    Science.gov (United States)

    Sujith, Ramachandra; Dhananjaya, Kiranmurthy; Chaurasia, Vishwajit Rampratap; Kasigari, Deepa; Veerabhadrappa, Anusha Channabasappa; Naik, Sachin

    2014-12-01

    The aim of this study was to evaluate the influence of using the dental operating microscope (DOM) and ultrasonics for the detection of second mesiobuccal (MB2) canal orifice in maxillary first molars. Sixty subjects seeking root canal therapy for maxillary first molar were assessed for the presence of MB2 canal using endodontic explorer without magnification. Teeth in which the MB2 canal orifice could not be located were examined under magnification using DOM. If the MB2 canal orifice could not be found even after using DOM, ultrasonic tips were used to prepare 3-mm-long trough from the mesiobuccal canal orifice toward the palatal canal and examined under DOM for location of the canal. With naked eye, the MB2 canal was located in 12 teeth; with the use of the DOM, the MB2 canal was located in 21 additional teeth; and with the combined use of ultrasonic tip and DOM, the MB2 canal was located in 9 more teeth. Statistical comparisons between the tested techniques were done by analyzing the Receiver Operating Characteristic (ROC) curves; a statistically significant difference was found (P < 0.001). The results of this study indicate that the DOM and ultrasonics provide increased opportunity for the dentist to detect canal orifices.

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

    Science.gov (United States)

    Pasha, Shiraz; Chaitanya, Bathula Vimala; Somisetty, Kusum Valli

    2016-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Temporal and Spatial Variation of Chemical Water Quality in a Contour Canal.

    Science.gov (United States)

    Swanson, L. A.; Lunn, R. J.

    2004-12-01

    Chemical water quality is a highly variable aspect of any water body. Historically numerous researchers have investigated the chemical variability of rivers, streams and wetlands, artificial water bodies such as canals have been largely neglected. Canals are typically hydraulically characterised by low flows and a lack of mixing processes. This can potentially lead to significant spatial variability in water chemistry, and as a result many canals in the UK regularly fail water quality targets at specific locations. Recent changes to UK legislation, following the European Water Framework Directive (2000/60/EC), have resulted in canals being subject to achieving `good ecological status'. In the case of canals, what constitutes `good ecological status' is largely unknown and little expertise is available since historically canal management has not been driven by chemical and ecological quality targets. Consequently, there is an urgent need for new research to determine the main factors influencing canal water quality and their ecological status. This research presents results from a study based on a UK contour canal, the Union Canal in central Scotland. The Union Canal typically demonstrates spatially and temporally variable levels of dissolved oxygen (DO) and orthophosphate (PO4-P): simultaneously, seasonal and diel fluctuations of DO and PO4-P are pronounced at a small number of locations. During 1995, minimum levels of DO along the canal length ranged from 9mgl-1 in Edinburgh to as low as 2mgl-1 approximately 20kms away, this then rose again to 8mgl-1 after a further distance of 2km. These acutely low levels of DO are coupled with events of excessive PO4-P up to 0.235mgl-1:10 times greater than those normally found in rivers, causing localised eutrophication and extensive fish kills. To determine the cause of the `hot spots' of poor water quality found on the Union Canal, simultaneous investigations of the hydraulic regime, spatial and temporal water quality

  19. Semicircular canal dehiscence: comparison of T2-weighted turbo spin-echo MRI and CT

    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 Veterinary Medicine, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany)

    2004-04-01

    We assessed the value of MRI for delineation of dehiscence of the superior or posterior semicircular canal, as compared with CT, the current standard study for this entity. We reviewed heavily T2-weighted fast spin-echo images and high-resolution CT of the temporal bones of 185 patients independently semicircular canal dehiscence and its extent. In 30 patients (19 men, 11 women) we identified dehiscence of the bone over the superior and/or posterior semicircular canal on MRI. In 27 of these cases CT also showed circumscribed bone defects. In one patient dehiscence of the superior semicircular canal was initially overlooked on MRI, but seen on CT. MRI imaging thus had a sensitivity of 96% and specificity of 98%. Knowledge of the appearances of this entity on MRI may contribute to early diagnosis in patients with vertigo due to semicircular canal dehiscence. (orig.)

  20. Prevalence of Internal Auditory Canal Diverticulum and Its Association with Hearing Loss and Otosclerosis.

    Science.gov (United States)

    Pippin, K J; Muelleman, T J; Hill, J; Leever, J; Staecker, H; Ledbetter, L N

    2017-11-01

    Focal low-attenuation outpouching or diverticulum at the anterolateral internal auditory canal is an uncommon finding on CT of the temporal bone. This finding has been described as cavitary otosclerosis in small case reports and histology series. The purpose of this study was to establish the prevalence of internal auditory canal diverticulum and its association with classic imaging findings of otosclerosis and/or hearing loss. Temporal bone CT scans of 807 patients, obtained between January 2013 and January 2016, were retrospectively reviewed to identify internal auditory canal diverticula and/or classic imaging findings of otosclerosis. Clinical evaluations for hearing loss were reviewed for patients with internal auditory canal diverticula and/or otosclerosis. Internal auditory canal diverticula were found in 43 patients (5%); classic otosclerosis, in 39 patients (5%); and both findings, in 7 patients (1%). Most temporal bones with only findings of internal auditory canal diverticula (91%) demonstrated hearing loss, with 63% of this group demonstrating sensorineural hearing loss. The hearing loss classification distribution was significantly different (P < .01) from that in the classic otosclerosis group and in the group with both diverticula and otosclerosis. Internal auditory canal diverticula are not uncommon on CT examinations of the temporal bone and most commonly occur without classic imaging findings of otosclerosis. These lesions are associated with sensorineural hearing loss, and referral for hearing evaluation may be appropriate when present. © 2017 by American Journal of Neuroradiology.

  1. Between Nature and Artifice: Villoresi Canal as Urban Infrastructure

    Directory of Open Access Journals (Sweden)

    Caterina Gallizioli

    2014-12-01

    Full Text Available In the strongly anthropized area between Ticino and Adda flows the Villoresi Canal, an hydraulic infrastructure able to link different parts of the land, spanning from agricultural landscape to residential areas. The Est Ticino Villoresi Consortium manages this infrastructure, dealing with the reclamation and irrigation of the area and adding value to these resources in terms of energy, landscape, tourism and environmental achievements. Through didactic experimentation and research, the synergy between the Consortium and the School of Civil Architecture of Politecnico di Milano means to express how this hydraulic infrastructure can become promoter of environmental reclamation and creator of new public open spaces for the collectivity. It is a matter of regeneration of a system of open spaces and physical modification of places related to water.

  2. Effects of metal- and fiber-reinforced composite root canal posts on flexural properties.

    Science.gov (United States)

    Kim, Su-Hyeon; Oh, Tack-Oon; Kim, Ju-Young; Park, Chun-Woong; Baek, Seung-Ho; Park, Eun-Seok

    2016-01-01

    The aim of this study was to observe the effects of different test conditions on the flexural properties of root canal post. Metal- and fiber-reinforced composite root canal posts of various diameters were measured to determine flexural properties using a threepoint bending test at different conditions. In this study, the span length/post diameter ratio of root canal posts varied from 3.0 to 10.0. Multiple regression models for maximum load as a dependent variable were statistically significant. The models for flexural properties as dependent variables were statistically significant, but linear regression models could not be fitted to data sets. At a low span length/post diameter ratio, the flexural properties were distorted by occurrence of shear stress in short samples. It was impossible to obtain high span length/post diameter ratio with root canal posts. The addition of parameters or coefficients is necessary to appropriately represent the flexural properties of root canal posts.

  3. Ab interno Schlemm's canal surgery: trabectome and i-stent.

    Science.gov (United States)

    Francis, Brian A; Winarko, Jonathan

    2012-01-01

    In primary open-angle glaucoma, the site of greatest resistance to aqueous outflow is thought to be the trabecular meshwork. Augmentation of the conventional (trabecular) outflow pathway would facilitate physiologic outflow and subsequently lower intraocular pressure. Ab interno Schlemm's canal surgery including two novel surgical modalities, Trabectome (trabeculotomy internal approach) and Trabecular Micro-bypass Stent (iStent), is designed to reduce intraocular pressure by this approach. In contrast to external filtration surgeries such as trabeculectomy and aqueous tube shunt, these procedures are categorized as internal filtration surgeries and are both performed from an internal approach via gonioscopic guidance. Published results suggest that these surgical procedures are both safe and efficacious for the treatment of open-angle glaucoma. Copyright © 2012 S. Karger AG, Basel.

  4. Housewife data: Citizen science and the case of Love Canal

    Science.gov (United States)

    Nicaise, Nolan M.

    Citizen science is defined as members of the public acting to produce science outside of their normal working lives in order to enhance or preserve their health, environment, knowledge, or capital. It is a science by the people. Over the last several decades, it has emerged as a powerful force for the democratization of science. In response to this growing trend in citizen science, this thesis addresses the question: What is citizen science? Citizen science is discussed through the development of a definition, its historical and political context, the benefits of its use, and some frameworks for understanding. Later, the thesis explores a case study of citizen science, the Love Canal environmental crisis, and offers commentary on its methods and findings.

  5. The cochlear nerve canal and internal auditory canal in children with normal cochlea but cochlear nerve deficiency

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Fei; Li, Jianhong; Xian, Junfang; Wang, Zhenchang [Dept. of Radiology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)], e-mail: cjr.wzhch@vip.163.com; Mo, Lingyan [Dept. of Otorhinolaryngology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)

    2013-04-15

    Background: There is an increasing frequency of requests for cochlear implantation (CI) in deaf children and more detailed image information is necessary for selecting appropriate candidates. Cochlear nerve deficiency (CND) is a contraindication to CI. Magnetic resonance imaging (MRI) has been used to evaluate the integrity of the cochlear nerve. The abnormalities of the cochlear nerve canal (CNC) and internal auditory canal (IAC) have been reported to be associated with CND. Purpose: To correlate CNC manifestation, size, and IAC diameter on high-resolution CT (HRCT) with CND diagnosed by MRI in children. Material and Methods: HRCT images from 35 sensorineurally deaf children who had normal cochlea but bilateral or unilateral CND diagnosed by MRI were studied retrospectively. The CNC and IAC manifestation and size were assessed and correlated with CND. Results: CND was diagnosed by MRI in 54/70 ears (77.1%). Thirty-two ears had an absent cochlear nerve (59.3%), while 22 ears had a small cochlear nerve (40.7%). The CNC diameter was <1.5 mm in 36 ears (66.7%). The CNC diameter ranged between 1.5 and 2.0 mm in seven ears (13.0%) and was >2.0 mm in 11 ears (20.4%). The IAC diameter was <3.0 mm in 25 ears (46.3%) and >3.0 mm in 29 ears (53.7%). Conclusion: The hypoplastic CNC might be more highly indicative of CND than that of a narrow IAC.

  6. Effects of canal enlargement and irrigation needle depth on the cleaning of the root canal system at 3 mm from the apex

    Directory of Open Access Journals (Sweden)

    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.

  7. Mines and Underwater IEDs in U.S. Ports and Waterways: Context, Threats, Challenges, and Solutions

    National Research Council Canada - National Science Library

    Truver, Scott C

    2008-01-01

    .... The threats of the Cold War are gone, and the United States finds itself operating in an environment where piracy, illegal migration, drug smuggling, terrorism, arms proliferation, and environmental...

  8. Discharge, suspended sediment, and salinity in the Gulf Intracoastal Waterway and adjacent surface waters in South-Central Louisiana, 1997–2008

    Science.gov (United States)

    Swarzenski, Christopher M.; Perrien, Scott M.

    2015-10-19

    Discharge, suspended sediment, and salinity data collected between 1997 and 2008 indicate that the Gulf Intracoastal Waterway (GIWW) is an important distributary of river water and suspended sediments to coastal wetlands in south-central coastal Louisiana. Following natural hydraulic gradients, the GIWW passively distributes freshwater and suspended sediments from the Atchafalaya River to areas at least 30 to 50 miles west and east, respectively, of Morgan City. The magnitude and reach of the discharge in the GIWW increase as stage of the Wax Lake Outlet at Calumet and Lower Atchafalaya River (LAR) at Morgan City increase. The magnitude and duration of discharge vary from year to year depending on the flow regime of the Atchafalaya River. Annual discharge of water in the GIWW was greater during years when stage of the LAR remained anomalously high throughout the year, compared with average and peak flood years. During years when Atchafalaya River flow is low, Bayou Boeuf, a waterway draining the Verret subbasin, becomes a major source of water maintaining the eastward flow in the GIWW. The GIWW is the only means of getting river water to some parts of coastal Louisiana.

  9. Mines and Underwater IEDs in U.S. Ports and Waterways: Context, Threats, Challenges, and Solutions

    Science.gov (United States)

    2008-01-01

    Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the...NUMBER OF PAGES 28 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298...remarks at Mine Warfare Command change of command, 8 July 1989, mimeo), p. 8. 13. See generally Moser Melia, “Damn the Tor- pedoes ”; Hartmann and

  10. Cancer of the anal canal and local control.

    Science.gov (United States)

    Valentini, V; Mantello, G; Luzi, S; Macchia, G; Manfrida, S; Smaniotto, D

    1998-01-01

    Concomitant radiochemotherapy is the standard treatment of squamous cell carcinoma of the anal canal. It can afford a high local control rate though the same impact has not been observed on survival. A few reports have concerned the impact of local control on distant metastases and survival. From 1988 to 1998 at the "Divisione di Radioterapia" of the "Università Cattolica del S. Cuore" of Rome 30 patients with squamous cell carcinoma of the anal canal were treated for cure. Treatment consisted of two cycles of radiotherapy (23.4 Gy) with a 4-5 week split in each cycle. 5FU (100 mg/sqm/24 h) was administered in continuous infusion for the first 4 days of therapy; mitomycin C (10 mg/sqm bolus) was administered on day 1, 4-6 weeks after the end of cycle 2 of concomitant radiochemotherapy, patients received a boost of interstitial brachytherapy. Local control on T of all patients was 84% at 5 years. Six patients showed locoregional recurrence: 3 recurrences on T and 4 disease progressions in locoregional lymph nodes. 3 of 6 patients underwent salvage surgery. The initial extent of the disease, the patient's age and brachytherapy boost did not have a statistically significant influence on local control. Two of the 30 patients showed liver metastases, and at their appearance, one patient was free of local disease while the other showed locoregional progression after Miles' operation for salvage. The metastasis-free interval was not significantly influenced by local control, although at 5 years, 96% of patients with local control of T were free of metastases vs 75% of those with recurrence on T (p = 0.22). Overall actuarial survival at 5 years was 75%. The behavior of survival in our experience seemed to be significantly influenced by local control: in the group with local control, 5-year survival was 85% vs 40% of patients with local recurrence (p = 0.01).

  11. Association of endodontic signs and symptoms with root canal pathogens: A clinical comparative study

    Directory of Open Access Journals (Sweden)

    R V Vineet

    2016-01-01

    Full Text Available Objective: The purpose of this study was to evaluate the association of the common root canal pathogens namely; Streptococcus mitis and Enterococcus faecalis with specific endodontic signs and symptoms. Materials and Methods: Sixty subjects scheduled for endodontic treatment were divided into two groups comprising of 30 subjects with primary endodontic infections and 30 subjects with failed endodontic treatment. The endodontic signs and symptoms of the subjects were assessed using clinical and radiographic methods. Root canal samples were collected using sterile paper point. Advanced microbiological culture techniques were used to isolate S. mitis and E. faecalis from the root canal samples. The presence of root canal pathogens was then correlated with the corresponding endodontic signs and symptoms. Statistical analysis was done using Student′s t-test and Fisher′s exact test. Results: S. mitis was significantly associated with pain and periapical lesions in primary and retreatment cases (P = 0.04. E. faecalis had a strong correlation with tenderness on percussion in retreatment cases (P = 0.016. Conclusion: Association of S. mitis with pain and periapical lesion, as well as E. faecalis with tenderness on percussion, suggests a correlation between endodontic signs and symptoms with specific root canal bacterial species. Knowledge regarding the association of root canal pathogens and specific endodontic signs and symptoms could help in better understanding and a predictable therapeutic management of root canal infections.

  12. Radiographic evaluation of root canal cleaning, main and laterals, using different methods of final irrigation

    Directory of Open Access Journals (Sweden)

    Gisselle Moraima CHÁVEZ-ANDRADE

    Full Text Available OBJECTIVE: To evaluate the efficacy of passive ultrasonic irrigation (PUI using intermittent or continuous flushing and conventional manual irrigation (CMI on the cleaning of main and simulated lateral root canals.MATERIAL AND METHOD: The root canals of 24 artificial teeth were prepared and simulated lateral canals were made in the medium and apical thirds of the root. The specimens were divided into three groups: G1- CMI, G2- PUI 1 (intermittent flushing and G3- PUI 2 (continuous flushing. Root canals were filled with contrast solution and the roots were radiographed pre- and post-irrigation. The digital images were transferred to Image Tool 3.0 software and the areas of root canal completely filled with contrast, and after irrigation with contrast remnant, were measured to obtain percentage data. Statistical analysis between groups was performed by ANOVA and Tukey tests.RESULT: In the apical third, G2 and G3 (PUI groups showed higher percentage of cleaning than G1 (CMI (p<0.05.CONCLUSION: Passive ultrasonic irrigation using intermittent flushing promoted a higher cleaning of simulated lateral canals than conventional manual irrigation in the apical third. There were no differences between groups in the main root canal and the middle third.

  13. Distribution and toxicity of sediment-associated pesticides in urban and agricultural waterways from Illinois, USA.

    Science.gov (United States)

    Ding, Yuping; Harwood, Amanda D; Foslund, Heather M; Lydy, Michael J

    2010-01-01

    A statewide investigation of insecticide presence and sediment toxicity was conducted in Illinois, USA, from June to August 2008. Twenty sediment samples were collected from urban areas throughout Illinois, and 49 sediment samples were collected from 14 agriculture-dominated counties in central and southern Illinois. Ten-day sediment toxicity tests were conducted using the amphipod Hyalella azteca, and 59% of the urban sites and 2% of the agricultural locations sampled caused significant mortality in the amphipods. The field sediments were analyzed for 29 pesticides, including 19 organochlorines, one organophosphate, and nine pyrethroids. The detection frequencies of organochlorines, chlorpyrifos, and pyrethroids were 95, 65, and 95%, respectively, for urban sites, and 45, 6.1, and 47%, respectively, for agricultural sites. Based on toxic unit analysis, bifenthrin was the main contributor to the detected mortality in urban sediments. The present study provides the first broad assessment of pesticide prevalence in both urban and agriculture areas in Illinois.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. A study of angle of mandibular canal and mental foramen on the panoramic radiograph

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Moon [Department of Oral and Maxillofacial Radiology and Oral Science Institute, College of Dentistry, Kangnung-Wonju National University, Kangnung (Korea, Republic of)

    2009-06-15

    To assessment the angle between mandibular canal and occlusal plane at each posterior tooth region and location of mental foramen on the panoramic radiographs. This study analysed 46 half-mandibles of panoramic radiographs. Inferior border of mandibular canal was traced. Occlusal plane was drawn from lingual cusp tip of the first premolar to distolingual cusp tip of the second molar. Perpendicular line from occlusal plane was drawn at each tooth region and then tangential lines were drawn from the crossing points at canal. The angle between occlusal plane and tangential line was measured. The location of mental foramen was also studied. According to the location of mental foramen, radiographs were divided into M (mesial) group and D (distal) group on the basis of the second premolar. and then inter-group analysis about mandibular canal angle was done. The angles of mandibular canals were -17.7 .deg. C, -9.5 .deg. C, 8.2 .deg. C, 22.3 .deg. C, and 39.2 .deg. C at first premolar, second premolar, first molar, second molar, and third molar, respectively. The commonest position of the mental foramen was distal to the second premolar. Inter-group comparison showed statistically significant difference at the second premolar and the first molar (p<0.001). The acknowledgement of mandibular canal angulation and location of mental foramen can help understanding the course of mandibular canal.

  16. Seepage Reduction from Unlined Irrigation Canals: Water Quality and Seepage Reduction Effectiveness

    Science.gov (United States)

    Susfalk, R. B.; Epstein, B. J.; Schmidt, M.; Goreham, J.; Fitzgerald, B.; Young, M. H.; Martin, C.; Swihart, J.; Smith, D.

    2006-12-01

    Polyacrylamide is a class of long-chain synthetic polymers that is used extensively in food packaging, paper manufacturing, wastewater treatment, and as a soil amendment to reduce erosion. More recently, linear, anionic polyacrylamides (LA-PAM) have been used to reduce seepage from unlined irrigation canals in the western United States. A diverse set of experiments spanning multiple scales has been initiated to understand the efficacy of LA-PAM usage in canal environments. The physical application of granular LA-PAM to flowing canals is straightforward. However, granular PAM requires time to hydrate and react with sediment suspended in the water column, complicating the targeting of a specific canal reach for treatment. Factors that influence PAM's ability to reduce seepage will be discussed, and can include: water temperature, water velocity, and the cation balance and suspended sediment concentration in the canal water. The application method and mass of PAM that are applied are also important considerations. If the ability of PAM to form flocs with suspended sediment is overestimated, PAM will travel further downstream, potentially having an adverse impact on water quality and/or ecology. Negative impacts include livestock drinking out of the canal, the unintentional reduction of seepage water feeding adjacent wetlands or sensitive areas, and impacts on receiving waters. A combination of results from working canals and small scale, artificial Test Troughs will be used to address the impacts that different LA-PAM applications can have on water quality and seepage reduction effectiveness.

  17. Lingual Foramina and Canals of the Mandible: Anatomic Variations in a Lebanese Population

    Directory of Open Access Journals (Sweden)

    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.

  18. Lingual Foramina and Canals of the Mandible: Anatomic Variations in a Lebanese Population

    Science.gov (United States)

    Aoun, Georges; Nasseh, Ibrahim; Sokhn, Sayde; Rifai, Mohamad

    2017-01-01

    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. PMID:28589055

  19. Prevalence of Enterococcus faecalis in saliva and filled root canals of teeth associated with apical periodontitis.

    Science.gov (United States)

    Wang, Qian-Qian; Zhang, Cheng-Fei; Chu, Chun-Hung; Zhu, Xiao-Fei

    2012-03-01

    To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis. Patients with apical periodontitis who were referred for endodontic retreatment were examined. The type and quality of the restoration, symptoms, quality of obturation were recorded. During retreatment, an oral rinse sample and root canal sample were cultured using brain-heart infusion agar and bile esculinazide agar to select for E. faecalis. The 16S rRNA technique was used to identify E. faecalis. A total of 32 women and 22 men (mean age: 38 years; s.d.: 11 years) and 58 teeth were studied. The prevalence of E. faecalis was 19% in the saliva and 38% in the root canals. The odds that root canals harbored E. faecalis were increased if the saliva habored this bacterium (odds ratio=9.7; 95% confidence interval=1.8-51.6; PTeeth with unsatisfactory root obturation had more cultivable bacterial species in root canals than teeth with satisfactory root obturation (Pfaecalis is more common in root canals of teeth with apical periodontitis than in saliva. The prevalence of E. faecalis in root canals is associated with the presence of E. faecalis in saliva.

  20. Antimicrobial efficacy of chloroxylenol and chlorhexidine in the treatment of infected root canals.

    Science.gov (United States)

    Schäfer, E; Bossmann, K

    2001-08-01

    To investigate the antimicrobial efficacy of a chlorhexidine gluconate (2.0%) and of an ethanolic chloroxylenol solution (10%) as a temporary root canal dressing against selected test microorganisms (Staphylococcus aureus, Streptococcus faecium, Escherichia coli, Candida albicans). Extracted single-rooted human teeth were instrumented up to size 40. After removal of the smear layer suspensions of the test microorganisms were inserted into the root canals. After incubation for 48 hrs each suspension of the test organisms was removed and the root canals were filled with one of the two different disinfectants. The teeth were then incubated for 48 hrs. Twelve teeth and three controls were used for each of the four test organisms and each of the two regimens. After incubation, each root canal was instrumented and the removed canal wall dentin was examined microbiologically. With a contact time of 48 hrs between the two disinfectants and the four bacterial suspensions the medications led to a total killing of microorganisms in 82% of a total of 96 contaminated teeth. In the dentin layer situated 50 microm from the root canal, both medications achieved bacterial killing in a range from 99.9% to 99.99%, depending on the test organism. There were no significant differences (P> 0.1) between the relative antimicrobial activity of the two root canal dressings.

  1. Anatomy and morphology of the nasopalatine canal using cone-beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Microbiological assessment of root canals following use of rotary and manual instruments in primary molars.

    Science.gov (United States)

    Subramaniam, Priya; Tabrez, T A; Babu, K L Girish

    2013-01-01

    To assess the microflora of root canals in primary molars following use of rotary NiTi files and conventional hand NiTi and stainless steel files. This randomized clinical trial consisted of a total of 60 first and second primary molars requiring root canal treatment, who were selected from children aged 5-9 years. Based on type of root canal instrumentation, the teeth were randomly assigned to three groups of twenty teeth each; Group A: Rotary NiTi files, Group B: Hand NiTi files and Group C: Hand stainless steel files. Following administration of local anesthesia, isolation with rubber dam was carried out. For the purpose of instrumentation and sampling, the palatal canal of maxillary molars and the distal canal of mandibular molars were selected. Prior to sampling, the orifices of other canals in these teeth were sealed, so as to prevent any contamination. Instrumentation was carried out in each group using respective instruments along with intermittent saline irrigation. Root canal samples were obtained both before and after instrumentation, using sterile absorbent paper points and transferred to a sterile vial with transport fluid. Serial dilutions were prepared and cultured on suitable agar media. Both aerobic and anaerobic microbial counts were made. Data obtained was subjected to statistical analysis using Wilcoxon signed rank test and one-way Analysis of variance. In all three groups, there was a significant reduction in both aerobic and anaerobic mean microbial count following root canal instrumentation. (p < 0.001). Rotary NiTi files were as efficient as conventional hand instruments in significantly reducing the root canal microflora.

  3. U.S. Navigated Waterway Mile Marker Locations from USCOE source data, Geographic NAD83, LOSCO (2000) [river_mile_markers_USACE_1994

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a point dataset representing 10,044 sequential mile positions of navigable inland waterways and the Gulf Intracoastal Waterway. These data were developed as...

  4. Graduate Education. Experiences and Preferences of WES (Waterways Experiment Station) Engineers and Scientists.

    Science.gov (United States)

    1987-03-01

    that education could aid in employee retention and that those planning to earn a master’s degree are a major target group. Percent of Work Force Current... employee retention has been ood: (only 13 are no longer employed -It WFS -Ind of these 2 have died ard at least 4 retired. Of the remaining .7 thought t

  5. Reactive nitrogen inputs to US lands and waterways: how certain are we about sources and fluxes?

    Science.gov (United States)

    An overabundance of reactive nitrogen (N) as a result of anthropogenic activities has led to multiple human health and environmental concerns. Efforts to address these concerns require an accurate accounting of N inputs. Here, we present a novel synthesis of data describing N inp...

  6. In vitro comparison of passive and continuous ultrasonic irrigation in simulated lateral canals of extracted teeth.

    Science.gov (United States)

    Castelo-Baz, Pablo; Martín-Biedma, Benjamín; Cantatore, Giuseppe; Ruíz-Piñón, Manuel; Bahillo, José; Rivas-Mundiña, Berta; Varela-Patiño, Purificación

    2012-05-01

    Complete endodontic system disinfection requires the removal of vital and necrotic pulp tissue, microorganisms, and toxins. The purpose of this study was to compare the effects of 2 ultrasonic irrigation techniques on the penetration of sodium hypochlorite into the main canal and simulated lateral canals of extracted teeth. Two simulated lateral canals each were created 2, 4, and 6 mm from the working length in 60 single-rooted teeth (6 canals/tooth, n = 360). To resemble the clinical situation, a closed system was created in each tooth. The teeth were randomly assigned to 3 experimental irrigation groups: group 1 (n = 20), positive pressure irrigation (PPI); group 2 (n = 20), passive ultrasonic irrigation (PUI); and group 3 (n = 20), continuous ultrasonic irrigation (CUI). Samples were evaluated by direct observation of still images recorded under a dental operating microscope. To examine irrigating solution penetration, 20% Chinese ink (Sanford Rotring GmbH, Hamburg, Germany) was added to a 5% sodium hypochlorite solution and delivered into the root canals. The results showed a significantly higher (P < .05) penetration of irrigant into the lateral canals in the CUI group. PUI and CUI did not differ significantly in solution penetration into the apical thirds of the main canals. The PPI group showed a significantly lower penetration of sodium hypochlorite into the main and lateral canals compared with the CUI and PUI groups. CUI as a final rinse significantly increased the penetration of irrigating solution into simulated lateral canals. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. Physicochemical Properties, Contamination and Suitability of Canal Water for Irrigation, Lahore Branch Pakistan

    Directory of Open Access Journals (Sweden)

    Tayyaba Aftab

    2011-12-01

    Full Text Available The pollution status of Lahore branch canal was determined by physical, chemical and metal constituents because the water is used for irrigation of lands in and around the city. The average result of each physical, chemical and metal parameter at 12 different sites (Location-1 to Location-12 of Lahore branch canal was compared with Food and Agricultural organization (FAO. All physical and chemical parameters were within standards limit while metals concentrations were found in variable quantities in canal water samples. cadmium, copper and chromium concentration was found much higher than the permissible FAO standards.

  8. 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

    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.

  9. Maxillary lateral incisors with two canals and two separate curved roots

    Directory of Open Access Journals (Sweden)

    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.

  10. Water quality of the Delaware and Raritan Canal, New Jersey, 1998-99

    Science.gov (United States)

    Gibs, Jacob; Gray, Bonnie; Rice, Donald E.; Tessler, Steven; Barringer, Thomas H.

    2001-01-01

    Since 1934, the Delaware and Raritan Canal has been used to transfer water from the Delaware River Basin to the Raritan River Basin. The water transported by the Delaware and Raritan Canal in New Jersey is used primarily for public supply after it has been treated at drinking-water treatment plants located in the Raritan River Basin. Recently (1999), the raw water taken from the canal during storms has required increased amounts of chemical treatments for removal of suspended solids, and the costs of removing the additional sludge or residuals generated during water treatment have increased. At present, action to control algae is unnecessary.

  11. Between China and Taiwan: the case of Nicaragua and the Grand Interoceanic Canal

    OpenAIRE

    Carmen Grau Vila

    2016-01-01

    The award of the concession of Nicaragua’s Grand Interoceanic Canal by the Sandinista Government to the Chinese company HKND seems less a response to a change in foreign policy in favour of continental China (at the expense of Taiwan), and more a step towards the achievement of a national Nicaraguan dream in which the investment company is from China. Nicaraguan history (linked for centuries to numerous canal projects), the diplomatic influence of Taiwan based on development cooperation, and ...

  12. [Comparative study of root canal morphology of mandibular first premolar by micro-CT and radio visio graphy].

    Science.gov (United States)

    Li, Xiangjie; Liu, Na; Liu, Rui; Dong, Zhengmou; Liu, Luchuan; Deng, Manjing

    2012-02-01

    To compare the consistency of root canal configuration types of mandibular first premolar by using micro-CT and radio visio graphy (RVG). One hundred extracted mandibular first premolars with complete dental root and apex which received no endodontic treatment were randomly selected. Each tooth was radiographed with RVG through a buccolingual and mesiodistal direction, and then scanned with micro-CT and reconstructed. The classifications of the root canal types according to Vertucci's type with the two methods were compared. The canal patterns were classified as type I (67%), type III (3%), type V (18%), type VII (2%), additional type (10%) with micro-CT and canal patterns as type I (71%), type III (2%), type V (23%), type VII (1%), additional type (3%) with RVG. 63% of teeth showed one canal in both micro-CT and RVG. Only 25% of teeth were diagnosed as complex canal by the same canal type in both micro-CT and RVG. The Kappa value between micro-CT and RVG was 0.541 which suggested that the two kinds of methods had intermediate consistency. 82.8% of the premolars with root groove had two or more than two canals. Although RVG can basically reflect the root canal system type of the mandibular first premolars in vitro, it offers poor accuracy images to complex root canals. Micro-CT three-dimensional images could clearly and precisely display the root canal system morphology of the mandibular first pre-molars in vitro.

  13. A rare case of maxillary first molar with single root and single canal diagnosed using spiral computed tomographic scan

    Directory of Open Access Journals (Sweden)

    Ajay Saxena

    2014-01-01

    Full Text Available Variations in dental anatomy and canal morphology are found in all teeth. Knowledge of these variations, particularly the location and treatment of all canals, plays a key role in the success of endodontic therapy. The presence of extra canals, apical ramification, or lateral canals is commonly encountered, and their incidence and significance have been well-documented. However, the clinician should also be aware of the possibility of the existence of fewer root and/or canal numbers. Here is a case report of left maxillary first permanent molar with a single root and single canal. The goal of this clinical article is to report a maxillary molar with single root and single canal and to highlight the role of spiral computed tomography (SCT as a method to confirm the three-dimensional (3D anatomy of teeth.

  14. The cartilage bone junction and its implications for deep canal hearing instrument fittings

    DEFF Research Database (Denmark)

    Nielsen, Claus; Darkner, Sune

    2011-01-01

    , or like talking in a barrel. This problem is caused by the occlusion effect. The effect is primarily due to vibrations of the walls in the soft part of the ear canal, which generate a sound pressure that is trapped in the cavity between the tip of the occluding hearing aid and the tympanic membrane....... If the hearing aid is fitted with a seal in the bony portion of the ear canal, preventing vibration in the soft part of the ear canal from reaching the tympanic membrane, then occlusion problems can be solved or at least reduced in most cases....

  15. 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.

  16. Projecting the Demand for Ohio River Basin Waterway Traffic Using Correlation and Regression.

    Science.gov (United States)

    1979-01-01

    chemicals. 3511 Machinery, except electrical botanical products and pharmaceitical Group 36-Electrical Machinery, preparations Equipment and Supplies 2841...Soap, detergents, and cleaning preparations: per- fumes, cosmetics and other toilet preparations 3611 Electrical machinery, equipment and supplies 2851

  17. Variations in the Root Form and Root Canal Morphology of Permanent Mandibular First Molars in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Roshan Peiris

    2015-01-01

    Full Text Available The present study was conducted to determine the number of roots and morphology of the root canal system of permanent mandibular first molars (M1 in a Sri Lankan population. Sample of 529 M1 teeth was used. The number of roots was examined and the lengths of the mesial and distal roots were measured to the nearest 0.01 mm. Vacuum injection protocol was used to inject China ink into the root canal system, making it transparent. Root canal morphology was recorded using Vertucci’s classification. Presence of furcation canals, position of lateral canals, intercanal communications, level of bifurcation, and convergence of the root canal system were recorded. M1 showed three roots in 4.1% of the sample. Commonest root canal morphology of the mesial root was type IV and the distal root was type I. The level of bifurcation of the root canals was commonly observed in the cervical one-third of the root while convergence was observed in the apical one-third in both roots. Prevalence of three rooted mandibular first molars is less than 5%. Mesial root showed the most variable canal morphology. Prevalence of furcation canals was 1.5% while that of middle mesial canals was 0.2%.

  18. National Waterway Network (line), Geographic WGS84, BTS (2006) [usace_nav_waterway_lin_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The National Waterway Network is a comprehensive network database of the nation's navigable waterways. The data set covers the 48 contiguous states plus the District...

  19. National Waterway Network (node), Geographic WGS84, BTS (2006) [usace_nav_waterway_nod_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The National Waterway Network is a comprehensive network database of the nation's navigable waterways. The data set covers the 48 contiguous states plus the District...

  20. Waterborne Commerce of the United States, Calendar Year 1986. Part 5. Waterways and Harbors, National Summaries

    Science.gov (United States)

    1988-05-31

    FRUIT AND REC JUICE, NEC.................... .............................................. 2,343,369 2,138,376 405,38? 2041 4HEAT FLOUR AND SEMOLINA ...2039 POEP FRUIT AND VEG JUICE, NEC...................................1:13 0 .........71,7 ,6 76406 2041 O.EAT FLOUR AND SEMOLINA ...1,092............ 3040 AHE4Y FLOUR AND SEMOLINA ................................................... 63, 79 40,166............... 33,#391

  1. Waterborne Commerce of the United States Calendar Year 1987. Part 3. Waterways and Harbors Great Lakes

    Science.gov (United States)

    1989-05-31

    2081 WHEAT FLOUR AND SEMOLINA ................. ?To......................737...SHELLFISH, PREPARED.................................................... 11 112 .............. .......... .......... 2041 WHEAT FLOUR AND SEMOLINA ...2 I7.............. .......... .......... 2041 MMEAT FLOUR AND SEMOLINA ............................................ft ........... 16.06s

  2. Waterway wide area tactical coverage and homing (WaterWATCH) program overview

    Science.gov (United States)

    Driggers, Gerald; Cleveland, Tammy; Araujo, Lisa; Spohr, Robert; Umansky, Mark

    2008-04-01

    The Congressional and Army sponsored WaterWATCH TM Program has developed and demonstrated a fully integrated shallow water port and facility monitoring system. It provides fully automated monitoring of domains above and below the surface of the water using primarily off-the-shelf sensors and software. The system is modular, open architecture and IP based, and elements can be mixed and matched to adapt to specific applications. The sensors integrated into the WaterWATCH TM system include cameras, radar, passive and active sonar, and various motion detectors. The sensors were chosen based on extensive requirements analyses and tradeoffs. Descriptions of the system and individual sensors are provided, along with data from modular and system level testing. Camera test results address capabilities and limitations associated with using "smart" image analysis software with stressing environmental issues such as bugs, darkness, rain and snow. Radar issues addressed include achieving range and resolution requirements. The passive sonar capability to provide near 100% true positives with zero false positives is demonstrated. Testing results are also presented to show that inexpensive active sonar can be effective against divers with or without SCUBA gear and that false alarms due to fish can be minimized. A simple operator interface has also been demonstrated.

  3. Waterborne Commerce of the United States Calendar Year 1987. Part 1. Waterways and Harbors Atlantic Coast

    Science.gov (United States)

    1989-05-31

    2043 WHEAT FLOUR AND SEMOLINA . ........................ ...... 220 ......----- ?20 ....................... ........ I...PREP, NEC--------------- - A .......... ...... ,2039 PREP FRUIT AND VEG JUICE, NEC 1.. 674--------------... :2041 0"t46 FLUJR AND SEMOLINA ...VEG JUICE, NEC----- ------------- ---- -25,273 24,881 392-- ....... .-......... .................... 2041 M’EAT FLOUR AND SEMOLINA

  4. Waterborne Commerce of the United States, Calendar Year 1986. Part 1. Waterways and Harbors, Atlantic Coast

    Science.gov (United States)

    1988-05-31

    I 14R4.......... .......... .......... .......... ........... ?041 aHET ELOU AND SEMOLINA ---....------------.--------- 22 .......... 2...PREP FRUIT AND VEG JUICE, NEC ......................... .. 330,617 12,255 12,407 2,926 ,969-.................... 2041 NHEAT FLOUR AND SEMOLINA ...47.40 4S.545 1,655.......... .................... .......... .......... 2041 dHEAT FLOUR AND SEMOLINA ................. . 14 ........... . .3

  5. Waterborne Commerce of the United States, Calendar Year 1980. Part 3. Waterways and Harbors, Great Lakes.

    Science.gov (United States)

    1982-09-01

    19.910 ------------------- 2041 WMEAT FLOUR AND SEMOLINA ----------99.592 -------------------------- 263 3Q049 ------------- 20,320...1,1697------------1,167 ----- --- .;......;--- 3041 WHEAT PIOUS AND SEMOLINA --------------------- 1:433 ------------- 1.433...DRIED MILK AND CREAM ----------------------- I-------------------A, -------------- 8,29 w --- -- ---- 2041 WHEAT FLOUR AND SEMOLINA

  6. Evaluation of root canal morphology of human primary molars by using CBCT and comprehensive review of the literature.

    Science.gov (United States)

    Ozcan, Gozde; Sekerci, Ahmet Ercan; Cantekin, Kenan; Aydinbelge, Mustafa; Dogan, Salih

    2016-01-01

    Knowledge of primary tooth morphology is essential for clinical dentistry, especially for root canal treatment and dental traumatology. However, this has not been well documented to date with a large sample. This study was carried out to investigate the variation in number and morphology of the root canals of the primary molars, to study the applicability of cone beam computerized tomography (CBCT) in assessing the same and to provide a comprehensive review of the literature. A total of 343 primary molars, without any root resorption, were divided into four main groups including the maxillary first molars, maxillary second molars, mandibular first molars and mandibular second molars. All of them were analysed in CBCT images in the axial, sagittal and coronal planes. Various parameters such as the number of roots, number of canals, the root canal type, diameter of root and root canal and root canal curvature were studied. Primary molars in all four groups showed variability in the number of roots and root canals. As far as length of the roots was concerned, the palatal root of the maxillary molar was found to be longest, while the distobuccal root was shortest. In mandibular molars, the mesial root was longer than the distal root. The length of distobuccal root canal of the maxillary molars and the distolingual canal of the mandibular molars was found to be shortest. The number of roots and root canals varied from two to four and three to four, respectively. The maxillary molars exhibited more one-canal than two-canal roots. The present study provides comprehensive information to the existing literature concerning the variation in root canal morphology of the maxillary and mandibular primary molar teeth. These data may help clinicians in the root canal treatment of these teeth.

  7. Evaluation of the relationship between crown size and root canal morphology of mandibular incisors by cone beam computed tomography (CBCT).

    Science.gov (United States)

    Ghamari, Maryam; Mollashahi, Narges Farhad; Salarpour, Mohammad; Mousavi, Elnaz; Kazemian, Kaveh; Moudi, Ehsan; Arab, Sepideh

    2017-08-01

    The main reason for the failure of endodontic therapy is the incomplete knowledge about the anatomical variation of root canals. One of the most important factors that leads to the failure of root canal treatment, is missed and untreated major root canals. with respect to the complexity of mandibular incisors treatment and high prevalence of the second canal, and the possibility of the relationship between the crown size and the extra canal in these teeth, the aim of this study was to determine the relationship between crown size and root canal morphology in mandibular incisors with CBCT. In this cross-sectional study, mandibular permanent incisors were randomly collected in Qazvin City, Iran, and were mounted in eight ternary groups on a plastic slot, using putty molding material. After preparation of Scot view, the samples were scanned by CBCT NewTom 5G. Afterward, the mesiodistal and buccolingual dimensions were measured by the software's measurement tool with a precision within tenths of a millimeter. In the next stage, a multi-planar option and 400% magnification tool of the software were utilized to study axial and cross sectional views of each tooth to determine canal type. Data were analyzed employing one-sample Kolmogorov-Smirnov, Levene, independent- samples t-test and Roc curve by SPSS version 20. The majority of mandibular incisors have a single canal (63.9% of them had type I canal system). In addition, 36.1% of the roots had two canals, among which, type III was the most common. The mean of maximum mesiodistal and buccolingual diameters in type III was significantly bigger than that in type I (p<0.05), but the means of crown size in the two canal types were not significantly different. Despite increase in mesiodistal and buccolingual dimension in two canal mandibular incisors with type III canal system, their crown sizes (M-D/F-L index) were not significantly different, in comparison to single canal incisors.

  8. 33 CFR 127.007 - Letter of intent and waterway suitability assessment.

    Science.gov (United States)

    2010-07-01

    ... management strategies; and (v) Resource needs for maritime safety, security, and response. (g) The Follow-on... is any change in the information submitted under paragraphs (c)(1) through (c)(7) of this section; or... must: (1) Annually review their WSAs and submit a report to the COTP as to whether changes are required...

  9. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength

    OpenAIRE

    Rippe, Marília Pivetta [UNESP; Manuela Favarin SANTINI; Bier, Carlos Alexandre Souza; BALDISSARA, Paolo; VALANDRO, Luiz Felipe

    2014-01-01

    Objective: To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. Material and Methods: eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments), the type of intraradicular post (fiber posts- FRC and cast post and core- CPC) and the use of mechanical cycling (MC) as follows: Manual and FRC; Manual, FRC and MC; Man...

  10. Sabine-Neches Waterway, Sabine Pass Jetty System: Past and Future Performance

    Science.gov (United States)

    2010-04-01

    direction) and the jetty composition (stone size/weight, number of armor layers, permeability and depth at the toe of the structure). To a certain extent...Nm = stability number Nz = t/Tm = number of waves at mean period during an event of duration t Tm = mean wave period P = structure permeability ...Chapter. 3. In Estuary and Coastline Dynamics, ed. A. T. Ippen. McGraw-Hill, Inc. Brown, G. L., M. S. Sarruff, R. Vemulakonda, G. H. Nail , J

  11. Ports and Waterways Safety Assessment Workshop Report for Passamaquoddy Bay, ME

    Science.gov (United States)

    2006-10-04

    discussed. The transit route from sea to Eastport consists of passage through the Bay of Fundy to Head Harbor Passage and Friar Roads. Vessels calling...Winds Today: • Most high winds occur in the winter. • Sustained winds oppose tides from Bay of Fundy and cause high, rough seas – problem for the...Ecotourism is increasing. • Extensive fisheries throughout of the Bay : − Commercial shell fishing, lobster , quahog, scallops; and fin fish…a year- round

  12. Prescribed burning plan : Stillwater NWR : Roadside ditches, canals, and brush piles

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This 1997 Annual Prescribed Burning Plan for Stillwater NWR calls for all units, roads, and delivery canals to be burned. The objective of this burn is to return...

  13. Real-Time Event Detection for Monitoring Natural and Source Waterways - Sacramento, CA

    Science.gov (United States)

    The use of event detection systems in finished drinking water systems is increasing in order to monitor water quality in both operational and security contexts. Recent incidents involving harmful algal blooms and chemical spills into watersheds have increased interest in monitori...

  14. Shipping, Ships and Waterways: A Marine Education Infusion Unit. Northern New England Marine Education Project.

    Science.gov (United States)

    Maine Univ., Orono. Coll. of Education.

    This multidisciplinary unit is designed to increase familiarity with various types of ships and purposes for different varieties of marine vessels. It seeks to increase familiarity with routes of ocean shipping and the effect of ocean conditions such as currents upon shipping route patterns. A discussion treats the uses of various navigation…

  15. Quantifying the effect of waterways and green areas on the surface temperature

    Directory of Open Access Journals (Sweden)

    Elis Dener Lima Alves

    2017-02-01

    Full Text Available The cooling effects of urban parks and green areas, which form the “Park Cool Island” (PCI can help decrease the surface temperature and mitigate the effects of urban heat islands (UHI. Therefore, the objective of this research was to know the temporal variability of PCI intensity, as well as analyze the factors that determines it and propose an equation to predict the PCI intensity in Iporá, Goiás State, Brazil. To this purpose, the PCI intensity values were obtained using the Landsat-8 satellite (band 10, and then correlated with the NDVI and the LAI, in which proposes equations through multiple linear regression to estimate the PCI intensity. The results indicated that: 1 the greater the distance of the natural area, greater the surface temperature; 2 there is a great seasonality in PCI, in which the intensity of PCI is much higher in the spring (or close to it; 3 the relationship between NDVI and LAI variables, showed good coefficients of determination; 4 the equations for the buffer of 200 and 500 m, had low RMSE with high coefficients of determination (r2 = 0.924 and r2 = 0.957 respectively.

  16. Environmental and Water Quality Operational Studies. Bibliography of Effects of Commercial Navigation Traffic in Large Waterways

    Science.gov (United States)

    1987-04-01

    aossage Physical force 12. launders Z1975) predicted ehio-Senerated bow-wave height (H) in deip vater vith the following equatiov: -kv (I/I) 0 ( V2 /2g...Ventilatory and Cough Frequencies in the Bluegill Lepomi8 maehrochirus and Brook Trout Salvelinus fonti- naZis ," Environmental Pollution Agency, Vol 34, pp

  17. Waterborne Commerce of the United States, Calendar Year 1982. Part 3. Waterways and Harbors, Great Lakes.

    Science.gov (United States)

    1984-07-01

    Wheat flour and semolina classified 2042 Animal feeds 0191 Miscellaneous farm products 2049 Grain mill products, not elsewhere classified 2061 Sugar... SEMOLINA ....-.....3,0......-......3,760,..-............--..... ......US AND• 810 LIM ....... * 2042 AIMAL FEEDS...............3...S4,536 4,3 9 50 17 20 2 DRIE MILK AND CREAM..... . . P.... .02 ..-...... ....02.1..02" 2040 WHEAT FLOUR ND SEMOLINA

  18. Bayou Segnette Waterway Dredged Material Placement Study Preliminary Assessment: Summary of Findings and Recommendations

    Science.gov (United States)

    2013-03-01

    Geological Survey Scientific Investigations Map 3080, scale 1:250,000, 6 p. pamphlet. Baustian, J.J., R.E. Turner, N.F. Walters, and D.P. Muth . 2009...Western Dredging Association – Thirty-Third Texas A & M Dredging Seminar. Mitsch, W. J., and J. G. Gosselink. 2000. Wetlands. 3d ed. New York: John

  19. Potential utilisation of sewage sludge and paper mill waste for biosorption of metals from polluted waterways.

    Science.gov (United States)

    Lister, S K; Line, M A

    2001-08-01

    The adsorption of cadmium, copper(II), lead and zinc ions from aqueous solution by sewage sludge, paper mill waste (PMW) and composted PMW was investigated along with the influence of pre-treatment on composted PMW. Langmuir adsorption isotherms were fitted where appropriate. Sewage sludge was the most effective biosorbent of the waste products for all metal ions examined, adsorbing, for example, up to 39.3 mg/g of Pb at an initial concentration of 77.8 mg/l. PMW was a less effective biosorbent than sewage sludge. However, it was found that composting the PMW resulted in an increase in metal uptake capacity and both sewage sludge and composted PMW have potential for low-cost remediation of high leachate wastewaters. The desorption of metal ions from PMW compost was most effective using 0.1 N H2SO4 and 1 mM nitrilotriacetic acid (NTA).

  20. Reductions in hepatic vitellogenin and estrogen receptor alpha expression by sediments from an agriculturally impacted waterway.

    Science.gov (United States)

    Sellin, Marlo K; Snow, Daniel D; Kolok, Alan S

    2010-01-31

    Previous studies have reported alterations in the endocrine function of fathead minnows (Pimephales promelas) collected and deployed in the Elkhorn River. The goal of the current study was to determine whether sediment from the Elkhorn River watershed could act as a source of endocrine-active compounds. To accomplish this, four aquaria containing sexually mature fathead minnows and polar organic chemical integrative samplers (POCIS) were established. The aquaria contained either: (1) laboratory water only, (2) Elkhorn River water only, (3) laboratory water and Elkhorn River sediment or (4) Elkhorn River water and Elkhorn River sediment. Steroid hormones were not detected in the extracts of POCIS or sediment. Pesticides were detected in POCIS extracts from tanks containing Elkhorn River water, but were not detected in the extracts of sediment or POCIS suspended in the tank containing laboratory water and Elkhorn River sediment suggesting that sediments do not act as a significant source of the 14 steroid hormones or 24 pesticides that were analyzed for in the current study. The hepatic mRNA expression of vitellogenin (vtg) and estrogen receptor alpha (ERalpha) in fathead minnows from each group was assessed. Female minnows exposed simultaneously to sediment and water collected from the Elkhorn River experienced defeminization as indicated by significant reductions in both vtg and ERalpha expression. Significant reductions in vtg mRNA expression were also observed in females exposed to laboratory water and Elkhorn River sediment, but not in females exposed to Elkhorn River water only. This finding suggests that exposures to sediments, rather than water, collected from the Elkhorn River lead to the defeminization of females. However, the compound(s) responsible for this effect have yet to be determined. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  1. The road less taken: modularization and waterways as a domestic disaster response mechanism.

    Science.gov (United States)

    Donahue, Donald A; Cunnion, Stephen O; Godwin, Evelyn A

    2013-01-01

    Preparedness scenarios project the need for significant healthcare surge capacity. Current planning draws heavily from the military model, leveraging deployable infrastructure to augment or replace extant capabilities. This approach would likely prove inadequate in a catastrophic disaster, as the military model relies on forewarning and an extended deployment cycle. Local equipping for surge capacity is prohibitively costly while movement of equipment can be subject to a single point of failure. Translational application of maritime logistical techniques and an ancient mode of transportation can provide a robust and customizable approach to disaster relief for greater than 90 percent of the American population.

  2. Estimated waterborne commerce statistics for calendar year 1998 : national totals and selected inland waterways

    Science.gov (United States)

    1999-07-30

    In order to provide waterborne commerce information as soon as possible, the Waterborne Commerce Statistics Center(WCSC) has prepared this summary document of estimated waterborne commerce statistics for calendar year 1998. The foreign import and exp...

  3. Estimated waterborne commerce statistics for calendar year 1996 : national totals and selected inland waterways

    Science.gov (United States)

    1997-10-01

    In order to provide waterborne commerce information as soon as possible, the Waterborne Commerce Statistics Center (WCSC) has prepared this summary document of estimated waterborne commerce statistics for calendar year 1996. The foreign import and ex...

  4. Waterborne Commerce of the United States, Calendar Year 1982. Part 1. Waterways and Harbors, Atlantic Coast.

    Science.gov (United States)

    1984-07-01

    43,18 S󈨏............................... ................. 3317 1RO AND STEL PIE AND TUBE..................9,564 49.666 175...TO UPPER END Of BERTH I, ARCO BALLAST WHARF, AUGUST 1982, 17.6 FEET TO PASTUNK AVENUE BRIDGE, (MINIMUM DEPTH IN RIGHT OUTSIDE QUARTER 24.0 FEET), 4...OELAPARF RIRE PROM ANT INCLOTINC, KIOFON’ POINT, DEL ., TO ,ANT INCLUrTOC.FOGERTOM,UL. 14 IES AN C.RITINA RIVE PR’ LAPAR VER T NEOPRT GEL,, 9 ILFS. CNT

  5. The Coast Guard Proceedings of the Marine Safety and Security Council. Waterways. Summer 2016

    Science.gov (United States)

    2016-01-01

    Photo courtesy of the Port of New Orleans. 47Summer 2016 Proceedingswww.uscg.mil/proceedings reducing the overall carbon footprint . The 12-acre ter...in the river system, potentially requiring more anchorage space as well as vessel services such as bunkering and stores, which also have a footprint ...from raw vegetable oil or animal fats and produced through a chemical process called transesterification. In the most common type of

  6. Assessment of Environmental Considerations in the Design and Construction of Waterway Projects.

    Science.gov (United States)

    1982-09-01

    W W W W W W W WW -𔃺 a reduction in available wildlife habitats, populations of birds, mam- mals, and reptiles will decrease accordingly. Species... Willamette , and Lower Mississippi Rivers. 156 W W W W W W W W S 1 Vegetation 327. Allen (1978) discusses the use of wetland plants to control erosion...environmental impact of grade-control structures is found in Part III of this report. Willamette River 0 demonstration project 348. Extensive bank

  7. Red River Waterway, Louisiana, Texas, Arkansas, and Oklahoma, Mississippi River to Shreveport, Louisiana. General Reevaluation Report.

    Science.gov (United States)

    1982-12-01

    project. The primary grass found in pastures is bermuda, although bahia , carpet, rye, dallis, bent, and Johnson grass are also present. Clovers...units. The population increased in direct response to a land grant offer which attracted American, French Canadian and Acadian immigrants . River...from Loggy Bayou north to the Hurricane Bluffs. The impediment of the Raft was not great enough to influence the rising number of immigrants intent on

  8. Development and Application of a Streamflow Disaggregation Tool in Natural Waterways

    Science.gov (United States)

    Acharya, A.; Ryu, J.

    2013-12-01

    A simple streamflow disaggregation method/tool has been developed to disaggregate streamflow from monthly to daily time steps. This disaggregation method is simple, site specific, data driven, flexible and adaptive at any regions and by any organizations that are looking for less intensive and less time consuming method of streamflow disaggregation from monthly to daily scale. The application of this methodology has been demonstrated through its application at both regulated and unregulated rivers located in Idaho. The flow indexes, which are developed with respect to historical data at the Source Station (SS), are applied to monthly streamflow at target station (TSS) while performing disaggregation. The selection of SS is based on minimum error criteria which is calculated for each 3-month seasonal flow volume for each year. An additional cubic spline interpolation is applied for unregulated cases to smoothen sudden high/low flows during month to month transition. The performance of this method to synthesize daily streamflow while preserving historical daily streamflow at both regulated and unregulated cases is evaluated based on different metrics such as statistical parameters, total runoff volume, peak runoff e.t.c.. The availability of finer scale (daily or shorter) hydrologic data can be utilized by water engineers in water resources management including reservoir operation, water quality and ecological modeling. This tool has been incorporated into the "PISCES" software program developed by the Bureau of Reclamation Pacific NorthWest Region (at http://www.usbr.gov/pn/hydromet/pisces) and this tool can also be directly assessed through http://water.cals.uidaho.edu/products/UIDisagg/ .

  9. Modelling cholera epidemics: the role of waterways, human mobility and sanitation.

    Science.gov (United States)

    Mari, L; Bertuzzo, E; Righetto, L; Casagrandi, R; Gatto, M; Rodriguez-Iturbe, I; Rinaldo, A

    2012-02-07

    We investigate the role of human mobility as a driver for long-range spreading of cholera infections, which primarily propagate through hydrologically controlled ecological corridors. Our aim is to build a spatially explicit model of a disease epidemic, which is relevant to both social and scientific issues. We present a two-layer network model that accounts for the interplay between epidemiological dynamics, hydrological transport and long-distance dissemination of the pathogen Vibrio cholerae owing to host movement, described here by means of a gravity-model approach. We test our model against epidemiological data recorded during the extensive cholera outbreak occurred in the KwaZulu-Natal province of South Africa during 2000-2001. We show that long-range human movement is fundamental in quantifying otherwise unexplained inter-catchment transport of V. cholerae, thus playing a key role in the formation of regional patterns of cholera epidemics. We also show quantitatively how heterogeneously distributed drinking water supplies and sanitation conditions may affect large-scale cholera transmission, and analyse the effects of different sanitation policies.

  10. Red River Waterway Sedimentation Study Downstream from Lock and Dam Number 1. Numerical Model Investigation

    Science.gov (United States)

    1988-06-01

    variations in the bed surface grada - tions, which appear to have little or no correlation to discharge. 14. The gradation of the bed material reservoir is...Orleans, 1980a). After a new bed material grada - tion was determined in this study, the water-surface profile adjustment was repeated and the final

  11. Medium and long term perspectives of Inland Waterway Transport in the European Union. Executive Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-01-15

    If inland shipping is to remain the greenest mode of transport, it will need to improve its environmental act in the coming years. If it fails to do so, it will be overtaken by road transport. That is one of the conclusions of the title study. In this study CE Delft performed the analyses of emissions and offers recommendations for reducing them. The key issue in this regard is to create financial incentives for ship owners to invest in modern, clean engines and retrofit technologies, complementing standards for new engines. The study will be used as a basis for drawing up policy on inland shipping towards 2020, in line with the EU White Paper on transport policy.

  12. Historic Resources Assessment, Tennessee-Tombigbee Waterway Wildlife Mitigation Project, Mobile and Tensaw River Deltas, Alabama

    Science.gov (United States)

    1993-03-01

    I Osborne, A.J. 1977 Strandloopers, Mermaids, and Other Fairy Tales : Ecologi- cal Determinants of Marine Resource Utilization. In For Theory Building...96.1 87.1: 90.0: TOTAL 46 14 77 85 40 262 17.6 5.3 29.4 32.4 15.3 100.0 CHI SQUARE = 4.25 with DF= 4 p value = 0.374 *l=Historic; 2=Protohistoric; 3

  13. Waterborne Commerce of the United States, Calendar Year 1980. Part 1. Waterways and Harbors, Atlantic Coast.

    Science.gov (United States)

    1982-09-01

    PIE ?, PRESIOENT ROADS ANCHORAGE, 3S FEET. PROJECT DEPYHI A CHANNEL 40 FEE? DEEP IN GRERAL.. BUT 49 FEE? THROUGH RICK 900 E HI , WIOENING AT THE OUTER...AVENUE ~IGE, PHILADELPH4IA, 1.1 "ILES. CONVROILLINO VI." I" MIDDLE HALF OF CHANNELI DECEMBER 1960. 31.4 FEET TO UPPER ENO Of BERTMI 01, ARCO BAL4AST WHIR...a 64 CRI DEL S A AND ALLICY E C GU--------------- --- --- 64 2- 6

  14. Otolith and Vertical Canal Contributions to Dynamic Postural Control

    Science.gov (United States)

    Black, F. Owen

    1999-01-01

    The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

  15. Waterborne Commerce of the United States, Calendar Year 1985. Part 3. Waterways and Harbors. Great Lakes.

    Science.gov (United States)

    1987-05-01

    IF AIVTA. CO9TROLLI9O 890 PROJECT 0EPTI4S£ 25 FEET 19 ESTRASCE C.SA9SEL5 21.23 PEEl £5 ToE TJASTID 901195 01 FEET 19 TOE 0I£E4 C9A9SEL TO RA8YLA9O...2478 115 1ER TI TNE JPvE0 0414102 L14173, 21 FEET: tjvsJ,; dASIN, 29 PEEl . V,46APAT11E STATEMENTIF 0 14 1 YEAR TONS 3954 TONS .......... 2902...60. HI Stoeport, With. ----------------- 50. 77 ontanagon Harbor, ich.-------- ---------- 49, 76 Sturgeon Hay and Lube Michigan Ship Mango Harbar

  16. Transportation Lines on the Mississippi River System and the Gulf Intracoastal Waterway; Transportation Series 4; 1980.

    Science.gov (United States)

    1982-05-01

    FUELING SERVICE C, 0. L0 A?1 4 VICKSBURG, MISS. 3918: 20 CHAPLIN TOWING, INC. 8?, 1 580IS, CHIO 43946 35 CHARITON COUNTv CONTRACTORS. WSY5 24 AND 65...KIRMIE C D0 47 12 6501 19,6 200 1 80 1000 - 69. NAST DO 00 1959 CHARLIE G TUG, S T EEL 58C :15 5D 225 220 6: 55, 1000 32.5, MAST 1 00 977 KENNY G D0...8217’- -AN:,N NAME A VEST’- ’’f AN -’ .7 %A j AN..A I[A (18 0-10 RIVER CO., 7sE (CO%TIN.,E01 CHARLIE C TOwBOAT, T.IN 10 809 640 240 20 ’- 7 6 113n 30, RADAR

  17. Cholesteatoma associated with squamous cell carcinoma of the external auditory canal: Case report and literature review

    Directory of Open Access Journals (Sweden)

    Olfa Ben Gamra

    2015-11-01

    Conclusion: SCC of the external auditory canal can mimic cholesteatoma. A precise diagnosis of the disease is important to predict the treatment outcome. Optimal management relies on early surgery and postoperative radiotherapy, thus offering the greatest chance of cure.

  18. Prevalence of Enterococcus faecalis in saliva and filled root canals of teeth associated with apical periodontitis

    OpenAIRE

    Wang, Qian-Qian; Zhang, Cheng-Fei; Chu, Chun-Hung; Zhu, Xiao-Fei

    2012-01-01

    To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis. Patients with apical periodontitis who were referred for endodontic retreatment were examined. The type and quality of the restoration, symptoms, quality of obturation were recorded. During retreatment, an oral rinse sample and root canal sample were cultured using brain-heart infusion agar and bile esculinazide agar to select for E. fa...

  19. Cone Beam Computed Tomographic Analysis of the Course and Position of Mandibular Canal.

    Science.gov (United States)

    Khorshidi, Hooman; Raoofi, Saeed; Ghapanchi, Janan; Shahidi, Shoaleh; Paknahad, Maryam

    2017-09-01

    Estimation of the relative position of infra alveolar nerve (IAN) canal and its relation to the mandibular anatomical landmarks can be clinically useful in minimizing the risk of surgery complications such as neurosensory disturbances that may occur after invasive mandibular surgical procedures. The purpose of the present study was to investigate the anatomic location and radiographic course of the mandibular canal compared to anatomic landmarks on CBCT and to discuss its clinical significance and also to determine the possible correlations between the mandibular position and the age of the patients. This cross sectional study was conducted on 242 CBCT of patients (99 males and 143 females). The location of canal was evaluated in 4 different regions. The first section in trans-axial view after mental foramen, in which the loop of mandibular canal is formed, was selected as point 1 for measurement and intervals of 10 mm, respectively, points 2, 3, 4 were selected for measurement. On these sections, the shortest linear distances (mm) from the most buccal and lingual aspects of the canal to the corresponding cortical plates of the mandible and also the minimum linear distance between the inferior aspect of canal and inferior border of mandible in these regions were calculated. There was statistically significant correlation between the anatomic course of the canal and the patients' gender. The mean vertical position of the canal, as measured from the lower border of the IAN canal to the inferior border of the mandible, was 8.50 mm, ranging from 4.80 to 14.50 mm. On average, the mandibular canal was situated more lingually at all sites to the point it reached the mental foramen. However, at the mental foramen region (Point 1), it was located closer to the buccal cortical plate. Assessment of the exact course of the IAN preoperatively along the body of the mandible by using CBCT might contribute to efficient and accurate surgical planning and therefore positively

  20. Endodontic management of mandibular second premolar with three roots and three root canals: A case report

    Directory of Open Access Journals (Sweden)

    Nidhi Shrivastava

    2014-01-01

    Full Text Available High level of success in endodontic treatment requires an understanding of root canal anatomy and morphology. The clinician must be prepared to identify those teeth that tend to vary generally from norm. Thorough debridement and obturation of such teeth can be challenging and failing to do so can lead to treatment failure. Mandibular premolars have earned the reputation for having aberrant anatomy. However, the occurrence of three separate canals with three separate foramina in mandibular premolars is very rare. The incidence of three canals is as high as 23% in mandibular first premolars, whereas in second premolars incidence is as low as 0.4%. Three rooted mandibular second premolar is reported to be 0.2%. This case report describes endodontic management of one such tooth with unusual morphological variations in canal anatomy of mandibular second premolar.

  1. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    Energy Technology Data Exchange (ETDEWEB)

    Pagliosa, Andre; Raucci-Neto, Walter; Silva-Souza, Yara Teresinha Correa; Alfredo, Edson, E-mail: ysousa@unaerp.br [Universidade de Ribeirao Preto (UNAERP), SP (Brazil). Fac. de Odontologia; Sousa-Neto, Manoel Damiao; Versiani, Marco Aurelio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Fac. de Odoentologia

    2015-03-01

    The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi) rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10), according to the biomechanical preparative system used: Hero 642 (HR), Liberator (LB), ProTaper (PT), and Twisted File (TF). The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05). The results demonstrated no significant difference (p > 0.05) in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR); -0.004 ± 0.044 mm (LB); -0.003 ± 0.064 mm (PT); -0.021 ± 0.064 mm (TF). The mean canal centering ability was: -0.093 ± 0.147 mm (HR); -0.001 ± 0.100 mm (LB); -0.002 ± 0.134 mm (PT); -0.033 ± 0.133 mm (TF). Also, there was no significant difference among the root segments (p > 0.05). It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape. (author)

  2. Relationship Among Anal Sphincter Injury, Patulous Anal Canal, and Anal Pressures in Patients with Anorectal Disorders

    Science.gov (United States)

    Prichard, David; Harvey, Doris M.; Fletcher, Joel G.; Zinsmeister, Alan R.; Bharucha, Adil E.

    2015-01-01

    Background & Aims The anal sphincters and puborectalis are routinely imaged with an endoanal magnetic resonance imaging (MRI) coil, which does not assess co-aptation of the anal canal at rest. Using a MRI torso coil, we identified a patulous anal canal in some patients with anorectal disorders. We aimed to evaluate the relationship between anal sphincter and puborectalis injury, a patulous anal canal, and anal pressures. Methods We performed a retrospective analysis of data from 119 patients who underwent MRI and manometry analysis of anal anatomy and pressures, respectively, from February 2011 through March 2013 at the Mayo Clinic. Anal pressures were determined by high-resolution manometry, anal sphincter and puborectalis injury was determined by endoanal MRI, and anal canal integrity was determined by torso MRI. Associations between manometric and anatomical parameters were evaluated with univariate and multivariate analyses. Results Fecal incontinence (55 patients, 46%) and constipation (36 patients. 30%) were the main indications for testing; 49 patients (41%) had a patulous anal canal, which was associated with injury to more than 1 muscle (all P≤.001) and internal sphincter (Panal resting pressure. A patulous anal canal was the only significant predictor (Panal squeeze pressure increment. Conclusions Patients with anorectal disorders commonly have a patulous anal canal, associated with more severe anal injury, anal resting pressure, and squeeze pressure increment. It is therefore important to identify patulous anal canal because it appears to be a marker of not only anal sphincter injury but disturbances beyond sphincter injury, such as damage to the anal cushions or anal denervation. PMID:25869638

  3. Scanning Electron Microscopic Evaluation of Root Canal Irrigation with Saline, Sodium Hypochlorite, and Citric Acid,

    Science.gov (United States)

    1983-12-01

    endodontic techniques; citric acid for root canal irrigation 4410,ABSTACgmf --,-,m- ,-rms n roc"---’This Study used a scanning electron microscope and a...wall is instrumented during canal preparation and that the smeared layer seems to be found only where endodontic instruments have scraped the surface...between the extremes. It was also decided to use a magnification of 75X to evaluate the superficial debris and 800X to evaluate the smeared layer

  4. Navigation Effects on Asian Carp Movement Past Electric Barrier, Chicago Sanitary and Ship Canal

    Science.gov (United States)

    2016-02-01

    were constructed of acrylic to allow observa- tion and video recording of model fish movement mechanisms beneath the barges. Because of their large...ER D C/ CH L TR -1 6- 2 Navigation Effects on Asian Carp Movement Past Electric Barrier, Chicago Sanitary and Ship Canal Co as ta l a...default. ERDC/CHL TR-16-2 February 2016 Navigation Effects on Asian Carp Movement Past Electric Barrier, Chicago Sanitary and Ship Canal

  5. Comparison of the accuracy of digital and conventional radiography in evaluation of curved canals lengths.

    Directory of Open Access Journals (Sweden)

    Ezoddini Ardakani F.

    2005-07-01

    Full Text Available Background and Aim: Proper shaping and cleaning of the root canal system is one of the most important aspects of endodontic treatment. To estimate the canal length before instrumentation in endodontic treatment, traditionally, conventional radiographic techniques and recently Direct Digital Radiography (DDR are applied. The application of computer technology to radiography has allowed less exposure time, image acquisition, manipulation, storage, retrieval, and transmission to remote sites in a digital format, elimination of wet processing and considerable reduction in the time lapse between image acquisition and display. The purpose of this study was to compare the accuracy of DDR versus conventional radiography in estimating endodontic file lengths of curved canals in first mandibular molars. Materials and Methods: In this test evaluation study, fourty extracted human first mandibular molars with root curvature were selected. Samples were divided into two groups: With root curvature less than 25 and more than 25. Samples were mounted in plaster blocks and canal lengths were estimated by using DDR and conventional radiographs. Regression analysis and correlation coefficient were used to calculate statistical differences between the groups with P<0.05 as the limit of significance. Results: Conventional radiography was more precise in canals with less than 25 degrees curvature (P=0.160. While, DDR was more precise for canals with curvature more than 25 degrees (P=0.605. However, these differences were not statistically significant. Conclusion: The image quality of DDR system has improved to the point that it can now be used for estimating canal lengths, even for curved canals, with accuracy comparable to that of conventional radiography.

  6. Interrelationships of petiolar air canal architecture, water depth, and convective air flow in Nymphaea odorata (Nymphaeaceae).

    Science.gov (United States)

    Richards, Jennifer H; Kuhn, David N; Bishop, Kristin

    2012-12-01

    Nymphaea odorata grows in water up to 2 m deep, producing fewer larger leaves in deeper water. This species has a convective flow system that moves gases from younger leaves through submerged parts to older leaves, aerating submerged parts. Petiolar air canals are the convective flow pathways. This study describes the structure of these canals, how this structure varies with water depth, and models how convective flow varies with depth. • Nymphaea odorata plants were grown at water depths from 30 to 90 cm. Lamina area, petiolar cross-sectional area, and number and area of air canals were measured. Field-collected leaves and leaves from juvenile plants were analyzed similarly. Using these data and data from the literature, we modeled how convective flow changes with water depth. • Petioles of N. odorata produce two central pairs of air canals; additional pairs are added peripherally, and succeeding pairs are smaller. The first three pairs account for 96% of air canal area. Air canals form 24% of petiolar cross-sectional area. Petiolar and air canal cross-sectional areas increase with water depth. Petiolar area scales with lamina area, but the slope of this relationship is lower in 90 cm water than at shallower depths. In our model, the rate of convective flow varied with depth and with the balance of influx to efflux leaves. • Air canals in N. odorata petioles increase in size and number in deeper water but at a decreasing amount in relation to lamina area. Convective flow also depends on the number of influx to efflux laminae.

  7. CBCT analysis of root canal morphology in geminated primary incisor: a proposed classification and case report.

    Science.gov (United States)

    Gandiban, Kanimozhi; Ramakrishnan, Mahesh

    2014-01-01

    Endodontic management of the geminated tooth requires a proper understanding of root canal morphology. The use of cone beam computed tomography (CBCT) in the diagnosis of complex endodontic morphology, and in revealing morphological variations, has been well documented in the literature. A case involving endodontic management of a geminated primary central incisor with CBCT is presented here. A CBCT analysis was vital in the diagnosis of this unusual root canal system and its successful endodontic treatment.

  8. Spiral computed tomographic evaluation and endodontic management of a mandibular first molar with three distal canals

    Science.gov (United States)

    Mushtaq, Mubashir; Farooq, Riyaz; Rashid, Aamir; Robbani, Irfan

    2011-01-01

    The use of spiral computed tomography serves as a boon in endodontic diagnosis of complex anatomic variations. The present case demonstrates the spiral tomographic evaluation and endodontic management of a mandibular first molar with 5 canals (2 mesial and 3 distal canals), which is a very rare anatomic variant. Such anatomic variations should be taken into account in day to day endodontic practice to ensure a high degree of clinical success. PMID:21814366

  9. Role of sediment in the design and management of irrigation canals : Sunsari Morang Irrigation Scheme, Nepal

    OpenAIRE

    Paudel, K.

    2010-01-01

    Sediment transport in irrigation canals The sediment transport aspect is a major factor in irrigation development as it determines to a large extent the sustainability of an irrigation scheme, particularly in case of unlined canals in alluvial soils. Investigations in this respect started since Kennedy published his channel-forming discharge theory in 1895. Subsequently different theories have been developed and are used around the world. All of them assume uniform and steady flow conditions ...

  10. A Fisheries Evaluation of the Richland and Wapato Canal Fish Screening Facilities, Spring 1987 : Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A.; Abernethy, C.Scott; Lusty, E.William; Wampler, Sally J.

    1988-02-01

    We evaluated the effectiveness of new fish screening facilities at the Richland and Wapato canals in south-central Washington State. The screen integrity tests at the Richland Screens indicated that 100% of fall chinook salmon fry (Oncorhynchus tshawytscha) released in front of the screens were prevented from entering the canal behind the screens. Our estimate is based on a 61% catch efficiency for control fish planted behind the screens. At the Wapato Canal, we estimated that between 3% and 4% of the test fish were either impinged on the screen surface and passed over the screens or passed through faulty screen seals. Our estimate is based over the screens or passed through faulty screen seals. Our estimate is based on a greater than 90% capture of control fish released in front of the screens. At the Wapato Screens, we estimated that 0.8% of steelhead smolts (Salmo gairdneri) and 1.4% of spring chinook salmon smolts released during low canal flow tests wee descaled. During full canal flow tests, 1.6% of the steelhead and 3.1% of the spring chinook salmon released were descaled. The fish return pipe at the Wapato Canal was tested: the estimate of descaled test fish wa not different from the estimate of descaled control fish. The time required for fish to exit from the Wapato Screen forebay varied with species and with canal flow. During low canal flows, 43.2% of steelhead and 61.6% of spring chinook salmon smolts released at the trash racks were captured in the fish return within 96 hr. 11 refs., 11 figs., 10 tabs.

  11. LPS levels in root canals after the use of ozone gas and high frequency electrical pulses

    Directory of Open Access Journals (Sweden)

    Tiago André Fontoura de MELO

    2016-01-01

    Full Text Available Abstract The present study aims to verify the effect of ozone gas (OZY® System and high frequency electric pulse (Endox® System systems on human root canals previously contaminated with Escherichia colilipopolysaccharide (LPS. Fifty single-rooted teeth had their dental crowns removed and root lengths standardized to 16 mm. The root canals were prepared up to #60 hand K-files and sterilized using gamma radiation with cobalt 60. The specimens were divided into the following five groups (n = 10 based on the disinfection protocol used: OZY® System, one 120-second-pulse (OZY 1p; OZY® System, four 24-second-pulses (OZY 4p; and Endox® System (ENDOX. Contaminated and non-contaminated canals were exposed only to apyrogenic water and used as positive (C+ and negative (C- controls, respectively. LPS (O55:B55 was administered in all root canals except those belonging to group C-. After performing disinfection, LPS samples were collected from the canals using apyrogenic paper tips. Limulus Amoebocyte Lysate (LAL was used to quantify the LPS levels, and the data obtained was analyzed using one-way ANOVA. The disinfection protocols used were unable to reduce the LPS levels significantly (p = 0.019. The use of ozone gas and high frequency electric pulses was not effective in eliminating LPS from the root canals.

  12. Effects of self-adjusting file, Mtwo, and ProTaper on the root canal wall.

    Science.gov (United States)

    Hin, Ellemieke S; Wu, Min-Kai; Wesselink, Paul R; Shemesh, Hagay

    2013-02-01

    The purpose of this ex vivo study was to observe the incidence of cracks in root dentin after root canal preparation with hand files, self-adjusting file (SAF), ProTaper, and Mtwo. One hundred extracted mandibular premolars with single canals were randomly selected. Two angulated radiographs were taken for each tooth, and the width of the canal was measured at 9 mm from the apex. Five groups of 20 teeth each were comparable in canal width. The control group was left unprepared. Four experimental groups were instrumented with hand files, ProTaper, Mtwo, and SAF. Roots were then sectioned horizontally and observed under a microscope. The presence of dentinal cracks and their location were noted. The difference between the experimental groups was analyzed with a χ(2) test. No cracks were observed in the control group. In the experimental groups, ProTaper, Mtwo, and SAF caused cracks in 35%, 25%, and 10% of teeth, respectively. The hand-file group did not show any dentinal cracks (P cracks than hand files (P .05). Instrumentation of root canals with SAF, Mtwo, and ProTaper could cause damage to root canal dentin. SAF has a tendency to cause less dentinal cracks as compared with ProTaper or Mtwo. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. The Syndrome of Enlarged Vestibule and Dysplasia of the Lateral Semicircular Canal in Congenital Deafness.

    Science.gov (United States)

    Lagundoye, S B; Martinson, F D; Fajemisin, A A

    1975-05-01

    A 5-year-old deaf-mute girl was shown on petrous bone tomography to have bilateral enlarged vestibules with assimilation of the lateral semicircular cannals, bilateral absence of the cochlea, aplasia of the left internal auditory canal with only the facial nerve compartment being present, and hypoplasia of the right internal auditory canal. The embryological basis of these inner ear abnormalities is discussed.

  14. Computed tomography evaluation of the morphometry and variations of the infraorbital canal relating to endoscopic surgery.

    Science.gov (United States)

    Açar, Gülay; Özen, Kemal Emre; Güler, İbrahim; Büyükmumcu, Mustafa

    2017-09-08

    The course of the infraorbital canal may leave the infraorbital nerve susceptible to injury during reconstructive and endoscopic surgery, particularly when surgically manipulating the roof of the maxillary sinus. We investigated both the morphometry and variations of the infraorbital canal with the aim to show the relationship between them relative to endoscopic approaches. This retrospective study was performed on paranasal multidetector computed tomography images of 200 patients. The infraorbital canal corpus types were categorized as Type 1: within the maxillary bony roof (55.3%), Type 2: partially protruding into maxillary sinus (26.7%), Type 3: within the maxillary sinus (9.5%), Type 4: located anatomically at the outer limit of the zygomatic recess of the maxillary bone (8.5%). The internal angulation and the length of the infraorbital canal, the infraorbital foramen entry angles and the distances related to the infraorbital foramen localization were measured and their relationships with the infraorbital canal variations were analyzed. We reported that the internal angulations in both sagittal and axial sections were mostly found in infraorbital canal Type 1 and 4 (69.2%, 64.7%) but, there were commonly no angulation in Type 3 (68.4%) (pCirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  15. Length and Geometric Patterns of the Greater Palatine Canal Observed in Cone Beam Computed Tomography

    Science.gov (United States)

    Howard-Swirzinski, Karen; Edwards, Paul C.; Saini, Tarnjit S.; Norton, Neil S.

    2010-01-01

    The greater palatine canal is an important anatomical structure that is often utilized as a pathway for infiltration of local anesthesia to affect sensation and hemostasis. Increased awareness of the length and anatomic variation in the anatomy of this structure is important when performing surgical procedures in this area (e.g., placement of osseointegrated dental implants). We examined the anatomy of the greater palatine canal using data obtained from CBCT scans of 500 subjects. Both right and left canals were viewed (N = 1000) in coronal and sagittal planes, and their paths and lengths determined. The average length of the greater palatine canal was 29 mm (±3 mm), with a range from 22 to 40 mm. Coronally, the most common anatomic pattern consisted of the canal traveling inferior-laterally for a distance then directly inferior for the remainder (43.3%). In the sagittal view, the canal traveled most frequently at an anterior-inferior angle (92.9%). PMID:20871845

  16. Nonsurgical root canal therapy of large cyst-like inflammatory periapical lesions and inflammatory apical cysts.

    Science.gov (United States)

    Lin, Louis M; Ricucci, Domenico; Lin, Jarshen; Rosenberg, Paul A

    2009-05-01

    It is a general belief that large cyst-like periapical lesions and apical true cysts caused by root canal infection are less likely to heal after nonsurgical root canal therapy. Nevertheless, there is no direct evidence to support this assumption. A large cyst-like periapical lesion or an apical true cyst is formed within an area of apical periodontitis and cannot form by itself. Therefore, both large cyst-like periapical lesions and apical true cysts are of inflammatory and not of neoplastic origin. Apical periodontitis lesions, regardless of whether they are granulomas, abscesses, or cysts, fail to heal after nonsurgical root canal therapy for the same reason, intraradicular and/or extraradicular infection. If the microbial etiology of large cyst-like periapical lesions and inflammatory apical true cysts in the root canal is removed by nonsurgical root canal therapy, the lesions might regress by the mechanism of apoptosis in a manner similar to the resolution of inflammatory apical pocket cysts. To achieve satisfactory periapical wound healing, surgical removal of an apical true cyst must include elimination of root canal infection.

  17. 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

  18. Distinct functions for netrin 1 in chicken and murine semicircular canal morphogenesis.

    Science.gov (United States)

    Nishitani, Allison M; Ohta, Sho; Yung, Andrea R; Del Rio, Tony; Gordon, Michael I; Abraira, Victoria E; Avilés, Evelyn C; Schoenwolf, Gary C; Fekete, Donna M; Goodrich, Lisa V

    2017-09-15

    The vestibular system of the inner ear detects head position using three orthogonally oriented semicircular canals; even slight changes in their shape and orientation can cause debilitating behavioral defects. During development, the canals are sculpted from pouches that protrude from the otic vesicle, the embryonic anlage of the inner ear. In the center of each pouch, a fusion plate forms where cells lose their epithelial morphology and the basement membrane breaks down. Cells in the fusing epithelia intercalate and are removed, creating a canal. In mice, fusion depends on the secreted protein netrin 1 (Ntn1), which is necessary for basement membrane breakdown, although the underlying molecular mechanism is unknown. Using gain-of-function approaches, we found that overexpression of Ntn1 in the chick otic vesicle prevented canal fusion by inhibiting apoptosis. In contrast, ectopic expression of the same chicken Ntn1 in the mouse otic vesicle, where apoptosis is less prominent, resulted in canal truncation. These findings highlight the importance of apoptosis for tissue morphogenesis and suggest that Ntn1 may play divergent cellular roles despite its conserved expression during canal morphogenesis in chicken and mouse. © 2017. Published by The Company of Biologists Ltd.

  19. Comparison of preparation of curved root canals with Hyflex CM and Revo-S rotary nickel-titanium instruments.

    Science.gov (United States)

    Bürklein, S; Börjes, L; Schäfer, E

    2014-05-01

    To compare the shaping ability of three different nickel-titanium rotary instruments during the preparation of curved root canals in extracted teeth. A total of 60 root canals with curvatures ranging between 25° and 35° were divided into three groups of 20 canals. Based on radiographs taken prior to instrumentation, the groups were balanced with respect to the angle and the radius of canal curvature. Canals were prepared to a final apical size of 35 using Mtwo, Hyflex CM, and Revo-S. Using pre- and post-instrumentation radiographs, straightening of the canal curvatures was determined with a computer image analysis program. Preparation time, changes of working length and instrument failures were also recorded. These data were analysed statistically using anova and Student-Newman-Keuls test. During preparation, no file fractured. Mtwo and Hyflex CM maintained the original canal curvature significantly better than Revo-S (P Hyflex CM was significantly faster than with Revo-S and resulted in less loss of working length (P Hyflex CM (P > 0.05). Under the conditions of this study, Mtwo and Hyflex CM respected the original canal curvature well and were safe to use. The use of Revo-S instruments required more time to prepare the curved canals and resulted in more pronounced canal straightening compared with Mtwo and Hyflex CM. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. In Vitro Comparative Study of the Working Length Determination with Radiovisiography and Conventional Radiography in Dilacerated Canals

    Directory of Open Access Journals (Sweden)

    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

  1. Retreatability of three calcium silicate-containing sealers and one epoxy resin-based root canal sealer with four different root canal instruments.

    Science.gov (United States)

    Donnermeyer, David; Bunne, Clarissa; Schäfer, Edgar; Dammaschke, Till

    2017-06-22

    The objective of the study was to compare the retreatability of three calcium silicate-containing sealers (BioRoot RCS, MTA Fillapex, Endo C.P.M.) and an epoxy resin-based sealer (AH Plus) with different root canal instruments (Hedström files, Reciproc R40, Mtwo retreatment file R 25/.05 + Mtwo 40/.06, and F6 SkyTaper) concerning sealer remnants and retreatment time. Root canals of 192 teeth were instrumented with Reciproc R40. All root canals were obturated using the single-cone technique with Reciproc R40 gutta-percha and one of the sealers (n = 48 per sealer). Two months later, retreatment was performed using one of the mentioned instruments (n = 12 per instrument and sealer). The roots were split longitudinally, and both halves were investigated using light microscopy. The percentage of sealer remnants covering the root canal wall was evaluated using the software ImageJ. The time required for retreatment was recorded. Statistical analysis was performed using two-way ANOVA and Student-Newman-Keuls post hoc test. Regarding the percentage of root canal filling remnants as well as retreatment time, two-way ANOVA indicated that the results were significantly affected by the sealer (p instrument used (p instruments allowed significantly faster retreatment than the other instruments (p instruments was superior compared to hand instrumentation. Engine-driven NiTi instruments are better suited to remove root canal fillings than stainless steel Hedström files.

  2. Post-embryonic development of canal and superficial neuromasts and the generation of two cranial lateral line phenotypes.

    Science.gov (United States)

    Becker, Emily A; Bird, Nathan C; Webb, Jacqueline F

    2016-10-01

    The relatively simple structural organization of the cranial lateral line system of bony fishes provides a valuable context in which to explore the ways in which variation in post-embryonic development results in functionally distinct phenotypes, thus providing a link between development, evolution, and behavior. Vital fluorescent staining, histology, and scanning electron microscopy were used to describe the distribution, morphology, and ontogeny of the canal and superficial neuromasts on the head of two Lake Malawi cichlids with contrasting lateral line canal phenotypes (Tramitichromis sp. [narrow-simple, well-ossified canals with small pores] and Aulonocara stuartgranti [widened, more weakly ossified canals with large pores]). This work showed that: 1) the patterning (number, distribution) of canal neuromasts, and the process of canal morphogenesis typical of bony fishes was the same in the two species, 2) two sub-populations of neuromasts (presumptive canal neuromasts and superficial neuromasts) are already distinguishable in small larvae and demonstrate distinctive ontogenetic trajectories in both species, 3) canal neuromasts differ with respect to ontogenetic trends in size and proportions between canals and between species, 4) the size, shape, configuration, physiological orientation, and overall rate of proliferation varies among the nine series of superficial neuromasts, which are found in both species, and 5) in Aulonocara, in particular, a consistent number of canal neuromasts accompanied by variability in the formation of canal pores during canal morphogenesis demonstrates independence of early and late phases of lateral line development. This work provides a new perspective on the contributions of post-embryonic phases of lateral line development and to the generation of distinct phenotypes in the lateral line system of bony fishes. J. Morphol. 277:1273-1291, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. 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

  4. The anatomical perspective of human occipital condyle in relation to the hypoglossal canal, condylar canal, and jugular foramen and its surgical significance

    Directory of Open Access Journals (Sweden)

    Ranjana Verma

    2016-01-01

    Conclusion: The OC and related structures such as HC, CC, and JF are likely to have variations in respect to morphometry and morphology. This study may prove helpful to neurosurgeons operating in this field, especially during TCA where neurovascular structures emerging from these canals and foramen are more vulnerable to injury.

  5. Neurovascular Content of the Mandibular Canal and Its Clinical Relevance: A Literature Review of the Related Anatomical and Radiological Studies

    OpenAIRE

    Eliades Apostolos N.; Manta Kalliopi H.; Tsirlis Anastasios T.

    2014-01-01

    In literature, anatomical variations of the inferior alveolar nerve branches (infratemporal, extraosseous and intraosseous) are reported and their importance in clinical practice is discussed too. The spatial vessels’ position in relationship with the nerve in the mandibular canal was explored, which is of clinical significance in impacted third molar and implant surgery. It is believed that the neurovascular content of the main mandibular canal follows any variations of the mandibular canal ...

  6. Compositional Approach to Distributed System Behavior Modeling and Formal Validation of Infrastructure Operations with Finite State Automata: Application to Viewpoint-Driven Verification of Functionality in Waterways

    Directory of Open Access Journals (Sweden)

    Mark A. Austin

    2018-01-01

    Full Text Available Now that modern infrastructure systems are moving toward an increased use of automation in their day-to-day operations, there is an emerging need for new approaches to the formal analysis and validation of system functionality with respect to correctness of operations. This paper describes a compositional approach to the multi-level behavior modeling and formal validation of large-scale distributed system operations with hierarchies and networks of finite state automata. To avoid the well-known state explosion problem, we develop a new procedure for viewpoint-action-process traceability, thereby allowing parts of a behavior model not relevant to a specific decision to be removed from consideration. Key features of the methodology are illustrated through the development of behavior models and validation procedures for polite conversation between two individuals, and lockset- and system-level concerns for ships traversing a large-scale waterway system.

  7. Position of mandibular canal and ramus morphology before and after sagittal split ramus osteotomy.

    Science.gov (United States)

    Ueki, Koichiro; Okabe, Katsuhiko; Miyazaki, Mao; Mukozawa, Aya; Marukawa, Kohei; Nakagawa, Kiyomasa; Yamamoto, Etsuhide

    2010-08-01

    The purpose of this study was to evaluate changes in the mandibular canal and ramus morphology before and after a sagittal split ramus osteotomy. The subjects were 30 patients (60 sides) with mandibular prognathism who had undergone bilateral sagittal split ramus osteotomy setback surgery. The mandibular canal position and ramus morphology were measured at the 3 horizontal planes under the mandibular foramen level (level A), 1 cm lower than level A (level B), and 2 cm lower than level A (level C) preoperatively and 1 year postoperatively by computed tomography. Postoperative ramus width, lateral distance, lateral marrow distance, and canal length were significantly larger than the preoperative values at the foramen, 1 cm lower, and 2 cm lower. The mandibular canal completely contacted the lateral cortex without lateral bone marrow in 6 sides (10%) in levels A and B and 4 sides (6.7%) in level C preoperatively and 6 sides (10%) in level C postoperatively. This study suggested that postoperative mandibular canal position was located more posteriorly and the postoperative lateral bone marrow became thicker compared with the preoperative state. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Hearing loss and enlarged internal auditory canal in children.

    Science.gov (United States)

    Santos, Saturnino; Domínguez, M Jesús; Cervera, Javier; Suárez, Alicia; Bueno, Antonio; Bartolomé, Margarita; López, Rafael

    2014-01-01

    Among the temporal bone abnormalities that can be found in the etiological study of paediatric sensorineural hearing loss (SNHL) by imaging techniques, those related to the internal auditory canal (IAC) are the least frequent. The most prevalent of these abnormalities that is associated with SNHL is stenotic IAC due to its association with cochlear nerve deficiencies. Less frequent and less concomitant with SNHL is the finding of an enlarged IAC (>8mm). Retrospective and descriptive review of clinical associations, imaging, audiological patterns and treatment of 9 children with hearing loss and enlarged IAC in the period 1999 to 2012. Two groups of patients are described. The first, without association with vestibulocochlear dysplasias, consisted of: 2 patients with SNHL without other temporal bone or systemic abnormalities, one with bilateral mixed HL from chromosome 18q deletion, one with a genetic X-linked DFN3 hearing loss, one with unilateral hearing loss in neurofibromatosis type 2 with bilateral acoustic neuroma, and one with unilateral hearing loss with cochlear nerve deficiency. The second group, with association with vestibulocochlear dysplasias, was comprised of: one patient with moderate bilateral mixed hearing loss in branchio-oto-renal syndrome, one with profound unilateral SNHL with recurrent meningitis, and another with profound bilateral SNHL with congenital hypothyroidism. The presence of an enlarged IAC in children can be found in different clinical and audiological settings with relevancies that can range from life-threatening situations, such as recurrent meningitis, to isolated hearing loss with no other associations. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  9. Anatomic variations and lesions of the mandibular canal detected by cone beam computed tomography.

    Science.gov (United States)

    Leite, Guilherme Mariano Fiuza; Lana, Juliana Pelinsari; de Carvalho Machado, Vinícius; Manzi, Flávio Ricardo; Souza, Paulo Eduardo Alencar; Horta, Martinho Campolina Rebello

    2014-10-01

    The mandibular canal is a significant anatomical structure in implant dentistry, and cone beam computed tomography (CBCT) is an important diagnostic image modality in this field of dentistry. The aim of this study was to evaluate the frequencies of anatomic variations and lesions affecting the mandibular canal in CBCT images of the mandible produced for dental implant planning. This cross-sectional study evaluated a sample of 250 CBCT examinations (500 mandibular canals). The inclusion criterion was CBCT examinations of the mandible requested for dental implant planning. The presence of anatomic variations and lesions affecting the mandibular canal was evaluated in the CBCT examinations. Moreover, the buccolingual position of the mandibular canal was evaluated in the molar region and in the ramus region. The CBCT exams were evaluated by one observer. The data were analyzed using descriptive and analytical statistics. The one-way ANOVA test was employed to compare the age between the anatomic variations. A paired t test was used to compare the buccolingual position between the molar region and the ramus region. Differences were considered significant when p values were lower than 0.05. The anatomic variations detected were large-diameter mandibular incisive canal (51.6 %), ramification (12 %), and accessory mental foramen (3.2 %). No difference was observed in the age of the patients between the anatomic variations (p > 0.05). The identified lesions included hypomineralization of the canal walls (20.8 %), idiopathic osteosclerosis (8.8 %), osteolytic lesions (3.2 %), iatrogenic perforation of the mandibular canal (2.8 %), and fibro-osseous lesions (1.6 %). The distance between the mandibular canal and the vestibular cortical bone was higher in the molar region than in the ramus region (p mandibular canal were common findings in the CBCT images of the mandible produced for dental implant planning. An awareness of these alterations is important for

  10. Entrainment, retention, and transport of freely swimming fish in junction gaps between commercial barges operating on the Illinois Waterway

    Science.gov (United States)

    Davis, Jeremiah J.; Jackson, P. Ryan; Engel, Frank; LeRoy, Jessica Z.; Neeley, Rebecca N.; Finney, Samuel T.; Murphy, Elizabeth A.

    2016-01-01

    Large Electric Dispersal Barriers were constructed in the Chicago Sanitary and Ship Canal (CSSC) to prevent the transfer of invasive fish species between the Mississippi River Basin and the Great Lakes Basin while simultaneously allowing the passage of commercial barge traffic. We investigated the potential for entrainment, retention, and transport of freely swimming fish within large gaps (> 50 m3) created at junction points between barges. Modified mark and capture trials were employed to assess fish entrainment, retention, and transport by barge tows. A multi-beam sonar system enabled estimation of fish abundance within barge junction gaps. Barges were also instrumented with acoustic Doppler velocity meters to map the velocity distribution in the water surrounding the barge and in the gap formed at the junction of two barges. Results indicate that the water inside the gap can move upstream with a barge tow at speeds near the barge tow travel speed. Water within 1 m to the side of the barge junction gaps was observed to move upstream with the barge tow. Observed transverse and vertical water velocities suggest pathways by which fish may potentially be entrained into barge junction gaps. Results of mark and capture trials provide direct evidence that small fish can become entrained by barges, retained within junction gaps, and transported over distances of at least 15.5 km. Fish entrained within the barge junction gap were retained in that space as the barge tow transited through locks and the Electric Dispersal Barriers, which would be expected to impede fish movement upstream.

  11. Formation of trihalomethanes of dissolved organic matter fractions in reservoir and canal waters.

    Science.gov (United States)

    Musikavong, Charongpun; Srimuang, Kanjanee; Tachapattaworakul Suksaroj, Thunwadee; Suksaroj, Chaisri

    2016-07-28

    The formation of trihalomethanes (THMs) of hydrophobic organic fraction (HPO), transphilic organic fraction (TPI), and hydrophilic organic fraction (HPI) of reservoir and canal waters from the U-Tapao River Basin, Songkhla, Thailand was investigated. Water samples were collected three times from two reservoirs, upstream, midstream, and downstream of the U-Tapao canal. The HPO was the major dissolved organic matter (DOM) fraction in reservoir and canal waters. On average, the HPO accounted for 53 and 45% of the DOM in reservoir and canal waters, respectively. The TPI of 19 and 23% in reservoir and canal waters were determined, respectively. The HPI of 29% of the reservoir water and HPI of 32% of the canal water were detected. For the reservoir water, the highest trihalomethane formation potential (THMFP)/dissolved organic carbon (DOC) was determined for the HPI, followed by the TPI and HPO, respectively. The average values of the THMFP/DOC of the HPI, TPI, and HPO of the reservoir water were 78, 52, and 49 µg THMs/mg C, respectively. The highest THMFP/DOC of the canal water was detected for the HPI, followed by HPO and TPI, respectively. Average values of the THMFP/DOC of HPI of water at upstream and midstream locations of 58 µg THMs/mg C and downstream location of 113 µg THMs/mg C were determined. Average values of THMFP/DOC of HPO of water at upstream and midstream and downstream locations were 48 and 93 µg THMs/mg C, respectively. For the lowest THMFP/DOC fraction, the average values of THMFP/DOC of TPI of water at upstream and midstream and downstream locations were 35 and 73 µg THMs/mg C, respectively.

  12. Premalignant Lesions of the Anal Canal and Squamous Cell Carcinoma of the Anal Canal

    Science.gov (United States)

    Poggio, Juan Lucas

    2011-01-01

    Squamous cell carcinoma of the anus (SCCA) is a rare tumor. However, its incidence has been increasing in men and women over the past 25 years worldwide. Risk factors associated with this cancer are those behaviors that predispose individuals to human papillomavirus (HPV) infection and immunosuppression. Anal cancer is generally preceded by high-grade anal intraepithelial neoplasia (HGAIN), which is most prevalent in human immunodeficiency virus-positive men who have sex with men. High-risk patients may benefit from screening. The most common presentation is rectal bleeding, which is present in nearly 50% of patients. Twenty percent of patients have no symptoms at the time of presentation. Clinical staging of anal cancer requires a digital rectal exam and a positron emission tomography/computed tomography scan of the chest, abdomen, and pelvis. Endorectal/endoanal ultrasound appears to add more-specific staging information when compared with digital rectal examination alone. Treatment of anal cancer prior to the 1970s involved an abdominoperineal resection. However, the current standard of care for localized anal cancer is concurrent chemoradiation therapy, primarily because of its sphincter-saving and colostomy-sparing potential. Studies have addressed alternative chemoradiation regimens to improve the standard protocol of fluorouracil, misogynic, and radiation, but no alternative regimen has proven superior. Surgery is reserved for those patients with residual disease or recurrence. PMID:22942800

  13. A novel generic optimization method for irrigation scheduling under multiple objectives and multiple hierarchical layers in a canal network

    Science.gov (United States)

    Delgoda, Dilini; Malano, Hector; Saleem, Syed K.; Halgamuge, Malka N.

    2017-07-01

    This research proposes a novel generic method for irrigation scheduling in a canal network to optimize multiple objectives related to canal scheduling (e.g. maximizing water supply and minimizing imbalance of water distribution) within multiple hierarchical layers (e.g. the layers consisting of the main canal, distributaries) while utilizing traditional canal scheduling methods. It is based on modularizing the optimization process. The method is theoretically capable of optimizing an unlimited number of user-defined objectives within an unlimited number of hierarchical layers and only limited by resource availability (e.g. maximum canal capacity and water limitations) in the network. It allows flexible decision-making through quantification of the mutual effects of optimizing conflicting objectives and is adaptable to available multi-objective evolutionary algorithms. The method's application is demonstrated using a hypothetical canal network example with six objectives and three hierarchical layers, and a real scenario with four objectives and two layers.

  14. EPA Proposes Rules to Improve Hazardous Waste Management and Better Protect our Waterways / New Rules Also Reduce Regulatory Burden on Businesses

    Science.gov (United States)

    WASHINGTON -- The U.S. Environmental Protection Agency (EPA) is proposing two new hazardous waste rules to strengthen environmental protection while reducing regulatory burden on businesses. One of the proposed rules will protect waterways, includin

  15. Radiography of the mandible prior to endosseous implant treatment. Localization of the mandibular canal and assessment of trabecular bone

    Energy Technology Data Exchange (ETDEWEB)

    Lindh, C.

    1996-03-01

    Mandibular autopsy specimens were examined with different radiographic techniques in order to evaluate the visibility of the mandibular canal and the measurement accuracy of distances related to the mandibular canal. Hypocycloidal, spiral and computed tomography (CT) were superior to periapical and panoramic radiography in visualizing the mandibular canal. The tomographic techniques were more accurate when measurements of distances related to the mandibular canal were performed. No difference in measurement accuracy was found between the tomographic techniques. Concerning visibility of the mandibular canal, interobserver agreement was lowest for periapical radiography and highest for CT. Intraobserver agreement was moderate or good for all techniques. A high interobserver variation was found for measurability of distances related to the mandibular canal. The trabecular bone tissue in mandibular autopsy specimens was studied concerning different characteristics. A classification system to be used prior to implant treatment, based on the trabecular pattern in periapical radiographs, was proposed. 74 refs.

  16. Cytotoxicity of 5% Tamarindus indica extract and 3% hydrogen peroxide as root canal irrigation

    Directory of Open Access Journals (Sweden)

    Erawati Wulandari

    2008-09-01

    Full Text Available Background: Preparation of root canal is an important stage in endodontic treatment. During conducting preparation, it is always be followed with root canal irrigation that has aim to clean root canal from necrotic tissue remains, grind down dentin powder, micro organism, wet the root canal to make preparation process of root canal easier, and solute root canal content at area that can not be reached by equipment. Flesh of Tamarindus indica (pulpa tamarindorum is used as traditional medicine and it contains vitamin C (antioxidant, protein, fat, glucose, etc. Previous research shows that 5% tamarindus indica extract can clean smear layer but it is more cytotoxicity to cell line BHK–21 than sterilized aquabides. Purpose: This research is to compare cytotoxicity between 5% Tamarindus indica extract with 3% H2O2 as root canal irrigation material. Method: Four teen culture cell line BHK 21 divides into 2 groups. Group 1 is treated with 3% H2O2 and Group 2 is treated with 5% Tamarindus indica extract, for about 2.5 minutes in every group. Then, living and death cell percentage is measured. Data is analyzed with independent t test with significant level of 0.05%. Result: The research showed that death cell in group 1 was 29.3% and in group 2 was 21.1%. There was a significant different (p < 0.05 between group 1 and group 2. Conclusion: Cytotoxicity of 5% Tamarindus indica extract to the cell line BHK–21 is lower than 3% H2O2.

  17. 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.

  18. In vivo antimicrobial efficacy of 6% Morinda citrifolia, Azadirachta indica, and 3% sodium hypochlorite as root canal irrigants

    OpenAIRE

    Podar, Rajesh; Kulkarni, Gaurav P.; Dadu, Shifali S.; Singh, Shraddha; Singh, Shishir H.

    2015-01-01

    Objective: To evaluate and compare the antimicrobial efficacy of 6% Morinda citrifolia, Azadirachta indica, and 3% sodium hypochlorite (NaOCl) as root canal irrigants. Materials and Methods: Thirty nonvital maxillary anteriors were randomly assigned to one of the three groups corresponding to the irrigant to be tested; 6% Morinda citrifolia juice (MCJ) (n = 10), A. indica (n = 10) and 3% NaOCl (n = 10). After the root canal access opening a root canal culture sample was taken with two paper p...

  19. EPA to approve Californias newest list of impaired waterways

    Science.gov (United States)

    SAN FRANCISCO - More than 40,000 miles of California's rivers and streams are currently threatened by pollution, according to a list of impaired waterways submitted by the state to the U.S. Environmental Protection Agency. Monitoring of rivers, lakes and

  20. Method for Constructing Standardized Simulated Root Canals.

    Science.gov (United States)

    Schulz-Bongert, Udo; Weine, Franklin S.

    1990-01-01

    The construction of visual and manipulative aids, clear resin blocks with root-canal-like spaces, for simulation of root canals is explained. Time, materials, and techniques are discussed. The method allows for comparison of canals, creation of any configuration of canals, and easy presentation during instruction. (MSE)

  1. Evaluate root and canal morphology of primary mandibular second molars in Chinese individuals by using cone-beam computed tomography

    Directory of Open Access Journals (Sweden)

    Ran Yang

    2013-07-01

    Conclusion: This study indicated that three-rooted PMSMs occur frequently in the Chinese population. There was no difference between the two genders on incidence and symmetry. The majority of PMSMs have three to four canals and the diversity of the root canal variants should be considered when performing clinical procedures. CBCT is a good option for studying the root and canal morphology of primary teeth.

  2. External auditory canal and middle ear cholesteatoma and osteonecrosis in bisphosphonate-treated osteoporosis patients

    DEFF Research Database (Denmark)

    Thorsteinsson, A-L; Vestergaard, P; Eiken, P

    2014-01-01

    UNLABELLED: Long-term treatment with bisphosphonates against osteoporosis may cause atypical femur fractures and osteonecrosis of the jaw. Eight cases of bisphosphonate-associated osteonecrosis of the external auditory canal area are published. Based on Danish national registers, we report a time......- and dose-dependent increased risk of cholesteatoma in osteoporosis patients treated with bisphosphonates. INTRODUCTION: In the recent years, there has been a focus on possible rare side effects of bisphosphonates (BPs). Eight cases of BP-associated osteonecrosis of the external auditory canal have been...... reported in the world literature. Our aim was to describe the incidence of external auditory canal and middle ear diseases in Danish patients exposed to BPs in the treatment of osteoporosis. METHODS: This register-based nationwide cohort study was conducted on the Danish population of approximately 5...

  3. ANALGESIC EFFICACY OF EPIDURAL MORPHINE AND CLONIDINEIN PATIENTS UNDERGOING DECOMPRESSION OF THE LUMBAR CANAL: A PROSPECTIVE RANDOMIZED TRIAL

    OpenAIRE

    RONCAGLIO, BRUNO; CALHAU, RAPHAEL FERNANDES; JACOB JÚNIOR, CHARBEL; CARDOSO, IGOR MACHADO; BATISTA JÚNIOR, JOSÉ LUCAS; ALMEIDA, JOELMAR CESAR

    2017-01-01

    ABSTRACT Objective: To evaluate the postoperative analgesic efficacy in patients undergoing lumbar canal decompression using epidural morphine and clonidine at the Hospital Santa Casa de Vitória - ES, Brazil. Methods: Prospective, randomized study of 60 patients with stenosis of the lumbar canal up to two levels with surgical indication, in which decompression of the canal was performed in association with lumbar arthrodesis. In group 1 we performed conventional postoperative analgesia and ...

  4. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength

    Directory of Open Access Journals (Sweden)

    Marília Pivetta RIPPE

    2014-06-01

    Full Text Available Objective: To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. Material and Methods: eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments, the type of intraradicular post (fiber posts- FRC and cast post and core- CPC and the use of mechanical cycling (MC as follows: Manual and FRC; Manual, FRC and MC; Manual and CPC; Manual, CPC and MC; Rotary and FRC; Rotary, FRC and MC; Rotary and CPC; Rotary, CPC and MC. The filling was performed by lateral compactation. All root canals were prepared for a post with a 10 mm length, using the custom #2 bur of the glass fiber post system. For mechanical cycling, the protocol was applied as follows: an angle of incidence of 45°, 37°C, 88 N, 4 Hz, 2 million pulses. All groups were submitted to fracture strength test in a 45° device with 1 mm/ min cross-head speed until failure occurred. Results: The 3-way ANOVA showed that the root canal preparation strategy (p<0.03 and post type (p<0.0001 affected the fracture strength results, while mechanical cycling (p=0.29 did not. Conclusion: The root canal preparation strategy only influenced the root fracture strength when restoring with a fiber post and mechanical cycling, so it does not seem to be an important factor in this scenario.

  5. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength

    Science.gov (United States)

    RIPPE, Marília Pivetta; SANTINI, Manuela Favarin; BIER, Carlos Alexandre Souza; BALDISSARA, Paolo; VALANDRO, Luiz Felipe

    2014-01-01

    Objective To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. Material and Methods eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments), the type of intraradicular post (fiber posts- FRC and cast post and core- CPC) and the use of mechanical cycling (MC) as follows: Manual and FRC; Manual, FRC and MC; Manual and CPC; Manual, CPC and MC; Rotary and FRC; Rotary, FRC and MC; Rotary and CPC; Rotary, CPC and MC. The filling was performed by lateral compactation. All root canals were prepared for a post with a 10 mm length, using the custom #2 bur of the glass fiber post system. For mechanical cycling, the protocol was applied as follows: an angle of incidence of 45°, 37°C, 88 N, 4 Hz, 2 million pulses. All groups were submitted to fracture strength test in a 45° device with 1 mm/ min cross-head speed until failure occurred. Results The 3-way ANOVA showed that the root canal preparation strategy (p<0.03) and post type (p<0.0001) affected the fracture strength results, while mechanical cycling (p=0.29) did not. Conclusion The root canal preparation strategy only influenced the root fracture strength when restoring with a fiber post and mechanical cycling, so it does not seem to be an important factor in this scenario. PMID:25025556

  6. Hydrographic and Ecological Effects of Enlargement of the Chesapeake and Delaware Canal. Appendix IV. Benthos of Delaware Waters in and Near C and D Canal.

    Science.gov (United States)

    1973-09-01

    grab and dredge samples, - as well as in fish stomachs , was Gammarus daiberi, Garveia frau— - ciscana, Linanodrilus op., Neomysis americana, Crangon ...of the Delaware portion of the Canal system. Addition of the two, shrimp—like crustaceans, Crangon and Neomysis, from the - - dredge rankings and...more frequently found in fish stomachs than abundant infauna]. organisms such as Limnodrilus. * Neomysis americana, a mysid shrimp , and Crangon

  7. Cross-sectional morphology and minimum canal wall widths in C-shaped roots of mandibular molars

    OpenAIRE

    Chai, W. L.; Thong, Y. L.

    2017-01-01

    The cross-sectional canal morphology and minimum widths of buccal and lingual canal walls were studied in 20 mandibular molars with C-shaped roots and canal orifices. The roots were mounted in clear resin blocks and sectioned transversely at 1-mm intervals. A total of 154 cross-sections were evaluated with an image analyzer. Twelve different longitudinal canal configurations were identified. The most prevalent were types 1-2 and 1-2-1 with each type occurring in four roots. Evaluation of the ...

  8. Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal

    Energy Technology Data Exchange (ETDEWEB)

    De Brito, Ana Caroline Ramos; Nejaim, Yuri; De Freitas, Deborah Queiroz [Dept. of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Sao Paulo (Brazil); De Oliveira Santos, Christiano [Dept. of Stomatology, Public Oral Health and Forensic Dentistry, School of Dentistry of Ribeirao Preto, University of Sao Paulo, Sao Paulo (Brazil)

    2016-09-15

    The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region.

  9. The cemento-dentino-canal junction, the apical foramen, and the apical constriction: evaluation by optical microscopy.

    Science.gov (United States)

    Ponce, Elías Harrán; Vilar Fernández, José Antonio

    2003-03-01

    The cemento-dentino-canal junction, the apical constriction, and the apical foramen are the principal reference points used to determine the apical limit for instrumentation and root canal filling. For a better understanding of these structures, the objective of this study was to evaluate histologically the localization of the cemento-dentino-canal junction and the diameters of the apical foramen and root canal at the cemento-dentino-canal junction. Eighteen anterior maxillary teeth (canines, central, and lateral incisors) were used, from which 269 histological sections were obtained and evaluated by optical microscopy. The results indicated that the longest extension of the cementum into the root canal was observed in the canines, this value decreasing in the lateral incisors, and even more so in the central incisors. The widest diameter of the apical foramen corresponded to the lateral incisors, followed by the canines and the central incisors. The diameter of the root canal at the cemento-dentino-canal junction was greatest in the canines and lowest in the central and lateral incisors. Great variability was observed in the measurements of the extension of the cementum into the root canal. AQ: 1.

  10. Nd:YAG Lasers Treating of Carious Lesion and Root Canal In Vitro

    Directory of Open Access Journals (Sweden)

    Danqing Xia

    2012-01-01

    Full Text Available Dental caries is a transmissible bacterial disease process, with cavities at the end, and caused by acids from bacterial metabolism. The essence of dental treatment is to clean and disinfect bacterial contamination from the tooth. In this work, we tried to demonstrate the cleaning and disinfecting effects of Nd:YAG laser irradiation on dental carious lesion and root canal in vitro. Acousto-optic Q-switched quasicontinuous and Cr3+:YAG crystal Q-switched pulse Nd:YAG lasers were employed to treat caries lesion and the root canal, respectively. Results showed that acousto-optic Q-switched quasicontinuous Nd:YAG laser irradiation and Cr3+:YAG crystal Q-switched pulse Nd:YAG laser irradiation could rapidly clean decayed material and bacterial contamination from dental carious lesion and the narrow tail end of root canal with minimally invasive in vitro, respectively. It was concluded that acousto-optic Q-switched quasicontinuous laser irradiation may be a rapid and effective alternative caries treatment, and Cr3+:YAG crystal Q-switched pulse Nd:YAG laser irradiation may be an effective method for canal cleaning and disinfecting during root canal therapy.

  11. Cyclic Fatigue Resistance of Reciproc Blue and Reciproc Files in an S-shaped Canal.

    Science.gov (United States)

    Topçuoğlu, Hüseyin Sinan; Topçuoğlu, Gamze

    2017-10-01

    This study evaluated the cyclic fatigue resistance (CFR) of Reciproc (R25 and R40; VDW, Munich, Germany) and Reciproc Blue (R25 and R40, VDW) instruments used in an artificial S-shaped canal. A total of 80 files were tested in an S-shaped canal (n = 20 for each file, Reciproc R25 and R40 and Reciproc Blue R25 and R40). This study compared Reciproc R25 with Reciproc Blue R25 files and Reciproc R40 with Reciproc Blue R40 files. All files were rotated in an S-shaped artificial canal until fracture. CFR was determined by recording the time to fracture in the artificial canal. The length of each fractured fragment was measured in millimeters. An independent sample t test was used to analyze the data. Between the R25 files, Reciproc Blue instruments showed significantly greater CFR than the Reciproc files in the apical and coronal curves (P Reciproc Blue instruments exhibited greater CFR in the apical and coronal curves (P Reciproc Blue files compared with the Reciproc files (P > .05). The Reciproc Blue R25 and R40 files showed greater CFR than the Reciproc R25 and R40 files in an S-shaped canal. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Comparison of Different Irrigants in the Removal of Endotoxins and Cultivable Microorganisms from Infected Root Canals.

    Science.gov (United States)

    Valera, Marcia Carneiro; Cardoso, Flávia Goulart da Rosa; Chung, Adriana; Xavier, Ana Cláudia Carvalho; Figueiredo, Mariana Diehl; Martinho, Frederico Canato; Palo, Renato Miotto

    2015-01-01

    This study was conducted to compare the effectiveness of different irrigants used to remove endotoxins and cultivable microorganisms during endodontic therapy. Forty root canals were contaminated and divided into groups according to the irrigant: 2% NaOCl + surfactant, 2% CHX, 2.5% NaOCl, and pyrogen-free saline solution (control). Samples were collected after root canal contamination (S1), after instrumentation (S2), and 7 days after instrumentation (S3). Microorganisms and endotoxins were recovered from 100% of the contaminated root canals (S1). At S2, 2% NaOCl + surfactant, 2% CHX, and 2.5% NaOCl were able to completely eliminate cultivable microorganisms. At S3, both 2% CHX and 2.5% NaOCl were effective in preventing C. albicans and E. coli regrowth, but E. faecalis was still detected. No microorganism species was recovered from root canals instrumented with 2% NaOCl + surfactant. At S2, a higher percentage value of endotoxin reduction was found for 2% NaOCl + surfactant (99.3%) compared to 2% CHX (98.9%) and 2.5% NaOCl (97.18%) (p endotoxins. All irrigants tested were effective in reducing microorganisms and endotoxins from root canals. Moreover, 2% NaOCl + surfactant was the most effective irrigant against endotoxins and regrowth of microorganisms.

  13. ALIMENTARY CANAL ANATOMY AND HISTOLOGY OF THE WORKER TERMITE NEOTERMES BOSEI

    Directory of Open Access Journals (Sweden)

    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.

  14. Root Canal Irrigation: Chemical Agents and Plant Extracts Against Enterococcus faecalis

    Science.gov (United States)

    Borzini, Letizia; Condò, Roberta; De Dominicis, Paolo; Casaglia, Adriano; Cerroni, Loredana

    2016-01-01

    Background: There are various microorganisms related to intra and extra-radicular infections and many of these are involved in persistent infections. Bacterial elimination from the root canal is achieved by means of the mechanical action of instruments and irrigation as well as the antibacterial effects of the irrigating solutions. Enterococcus faecalis can frequently be isolated from root canals in cases of failed root canal treatments. Antimicrobial agents have often been developed and optimized for their activity against endodontic bacteria. An ideal root canal irrigant should be biocompatible, because of its close contact with the periodontal tissues during endodontic treatment. Sodium hypoclorite (NaOCl) is one of the most widely recommended and used endodontic irrigants but it is highly toxic to periapical tissues. Objectives: To analyze the literature on the chemotherapeutic agent and plant extracts studied as root canal irrigants. In particularly, the study is focused on their effect on Enterococcus faecalis. Method: Literature search was performed electronically in PubMed (PubMed Central, MEDLINE) for articles published in English from 1982 to April 2015. The searched keywords were “endodontic irrigants” and “Enterococcus faecalis” and “essential oil” and “plant extracts”. Results: Many of the studied chemotherapeutic agents and plant extracts have shown promising results in vitro. Conclusion: Some of the considered phytotherapic substances, could be a potential alternative to NaOCl for the biomechanical treatment of the endodontic space. PMID:28217184

  15. The surgical challenge of carotid artery and Fallopian canal dehiscence in chronic ear disease: a pitfall for endoscopic approach.

    Science.gov (United States)

    Pauna, H F; Monsanto, R C; Schachern, P A; Costa, S S; Kwon, G; Paparella, M M; Cureoglu, S

    2017-04-01

    Endoscopic procedures are becoming common in middle ear surgery. Inflammation due to chronic ear disease can cause bony erosion of the carotid artery and Fallopian canals, making them more vulnerable during surgery. The objective of this study was to determine whether or not chronic ear disease increases dehiscence of the carotid artery and Fallopian canals. Comparative human temporal bone study. Otopathology laboratory. We selected 78 temporal bones from 55 deceased donors with chronic otitis media or cholesteatoma and then compared those two groups with a control group of 27 temporal bones from 19 deceased donors with no middle ear disease. We analysed the middle ear, carotid artery canal and Fallopian canal, looking for signs of dehiscence of its bony coverage, using light microscopy. We found an increased incidence in dehiscence of the carotid artery and Fallopian canals in temporal bones with chronic middle ear disease. The size of the carotid artery canal dehiscence was larger in the middle ear-diseased groups, and its bony coverage, when present, was also thinner compared to the control group. Dehiscence of the carotid artery canal was more frequently located closer to the promontory. The incidence of Fallopian canal dehiscence was significantly higher in temporal bones from donors older than 18 years with chronic middle ear disease. The increased incidence of the carotid artery and Fallopian canal dehiscence in temporal bones with chronic middle ear disease elevates the risk of adverse events during middle ear surgery. © 2016 John Wiley & Sons Ltd.

  16. Comparative analysis of root canal anatomy after mechanical preparation with hyflex CM TM and hyflex EDM TM

    OpenAIRE

    Amorim, Luana Silva

    2016-01-01

    Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2016 INTRODUCTION: One of the primary goals of root canal preparation is following the original anatomy of the canal, maintaining the root canal curvature and the spatial relationship of the apical foramen to periapical tissues and root surface. The aims of this study are to evaluate maintenance of the original canal anatomy when comparing two different rotary systems, HyFlex CM™ and HyFlex EDM™, a...

  17. [Materials and technics in root canal treatments in Switzerland--a determination of their status].

    Science.gov (United States)

    Barbakow, F; Lutz, F; Toth, L

    1995-01-01

    No data is available on either the materials nor techniques used by Swiss clinicians when doing root canal therapy (RCT). Consequently, in January 1993 questionnaires were posted to all dentists registered with the Swiss Dental Association, excluding those known not to practice RCT. Sixteen questions were answered detailing the disinfecting and obturating materials used, which types of files, preparation and obturation techniques were used and which radiographs were taken during RCT. Demographic details were also answered. Of the 3353 questionnaires posted, 2091 (62.4%) were completed and returned. Major results showed that 50.6% of the responding clinicians used AH26 to obturate canals, 45% Endomethasone and 36.6% N2. Canals were disinfected using Ledermix (81.2%), Asphaline (67.6%), Ca(OH)2 (60.2%). Clinicians used H2O2 and NaOCl equally frequently (75%). Hedstroem files, reamers and flexofiles were used by 52%, 29% and 26% of the clinicians, respectively. Canals were obturated by single-cone technique (68%), lateral condensation (34%), or by using only a paste or sealer (23%). 86.4% take a diagnostic radiograph, 69.2% determine working length from radiographs, and 91.5% take a final radiograph as well. Too many Swiss clinicians still use formaldehyde-containing products in root canal therapy coupled with a "single cone" or a "no cone" obturation technique.

  18. Effectiveness of castor oil extract on Escherichia coli and its endotoxins in root canals.

    Science.gov (United States)

    Valera, Marcia Carneiro; Maekawa, Lilian Eiko; Chung, Adriana; de Oliveira, Luciane Dias; Carvalho, Claudio Antonio Talge; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2012-01-01

    This in vitro study sought to evaluate the effectiveness of castor oil extract used as an irrigating solution on Escherichia coli and its endotoxins in root canals. Sixty single-rooted teeth were prepared (using castor oil extract as irrigating solution) and divided into five groups (n = 12): Group 1 samples were treated with calcium hydroxide (Ca(OH)2), Group 2 samples were treated with polymyxin B, Group 3 samples were treated with Ca(OH)2 and 2% chlorhexidine gel (CHX), and Group 4 samples were treated with castor oil extract. A control group used physiological saline solution as an irrigant. Canal content samples were collected at four different times: immediately after instrumentation, seven days after instrumentation, after 14 days of intracanal medication, and seven days after removal of intracanal medication. A plating method was used to assess antimicrobial activity and the quantification of endotoxins was evaluated by the chromogenic Limulus lysate assay. Data were submitted to ANOVA and a Dunn test (a = 5%). Irrigation with castor oil extract decreased E. coli counts but had no effect on the level of endotoxins. Samples taken seven days after removal of medication revealed a significant reduction in endotoxin levels in Groups 3 and 4. Compared to the saline solution irrigation, castor oil extract decreased microorganism counts in root canals immediately after canal preparation. None of the medications used completely eliminated endotoxins in the root canal.

  19. Finite element modelling of the canine and feline outer ear canal: benefits for local drug delivery?

    Science.gov (United States)

    Wefstaedt, Patrick; Behrens, Bernd-Arno; Nolte, Ingo; Bouguecha, Anas

    2011-01-01

    Current therapeutic regimes of outer ear infections in dogs and cats aim at the application of efficient local therapeutics after cleaning of the acoustic meatus. One so far insufficiently answered question is if the local application of these substances results in an individually suitable drug concentration in the external ear canal. Thus, the purpose of the present study was to develop a finite element model to calculate the values of the different areas of the external acoustic meatus in dogs and cats in order to provide a tool for the benefit of an appropriate local drug dosage determination. A 3D finite element model (FEM), based on computer tomographic (CT) data sets of four dogs and two cats, was generated to determine areas and volumes of the outer ear canal. Furthermore, various ear therapeutics and cleansers were tested concerning their optimal distribution on 5 cm2 dog and cat skin. The data shows major variations of the area values of the external auditory canal in case of the different dogs but not in the examined cats. These results suggest that manufacturer's recommendations of the pharmaceuticals might be insufficient in terms of achieving an optimal drug concentration in the outer ear canal especially in larger dogs. In conclusion, the developed finite element model has shown to be suitable to calculate areas of the outer ear canal in cats and dogs and could be of help in context with the definition of optimal drug concentrations for a local drug delivery.

  20. Efficacy of bacterial removal from instrumented root canals in vitro related to instrumentation technique and size.

    Science.gov (United States)

    Rollison, Scott; Barnett, Frederic; Stevens, Roy H

    2002-09-01

    This in vitro investigation assessed the efficacy of removing radioactively labeled bacteria from infected canals with 2 engine-driven rotary nickel titanium instrumentation techniques differing in sequence and apical enlargement size. A standard quantity of (3)H-thymidine-labeled Enterococcus faecalis (3.70 x 10(4) cpm, 2.0 x 10(7) colony-forming units) was used to inoculate the mesiobuccal canals of 50 extracted mandibular molars. The teeth were incubated for 5 days to allow infection of the surrounding dentin from the canals. Five of the teeth were used as controls to determine the number of cycles of irrigation and drying necessary to reduce the (3)H counts recovered from the canals to baseline levels. After this process, the unbound bacteria in the root canals of the remaining 45 teeth then were washed out with buffer until baseline levels of radioactivity were obtained. The mesiobuccal root of 1 of these 45 teeth was removed, decalcified, and digested, and the total radioactivity released from the root dentin was measured. Of the remaining 44 teeth, 22 then were instrumented with GT and Profile (Dentsply/Tulsa Dental Co, Tulsa, Okla) instruments to apical size #35 (group 1) and 22 teeth with Pow-R instruments (Moyco/Union Broach, York, Pa) to apical size #50 (group 2), in the presence of a standard quantity of phosphate-buffered saline solution placed in the canal. After instrumentation, the medium from each canal was collected with paper points and its radioactivity was counted with liquid scintillation spectrometry. The mean (3)H level recovered with instrumentation of canals in group 1 was 75 cpm (+/- 29, standard deviation) and in group 2 was 123 cpm (+/- 50, standard deviation). A 2-tailed Mann-Whitney test indicated that the radioactivity of samples from group 2 was significantly higher than that of samples from group 1. The results suggested that instrumentation to an apical size of #50, as performed with the Pow-R instruments, was more effective in

  1. Dimensions of the lumbar spinal canal: variations and correlations with somatometric parameters using CT

    Energy Technology Data Exchange (ETDEWEB)

    Karantanas, A.H. [Department of CT-MRI, Larissa General Hospital (Greece); Zibis, A.H.; Papaliaga, M.; Georgiou, E.; Rousogiannis, S. [Larissa Medical School, University of Thessaly, Larissa (Greece)

    1998-12-01

    The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient. (orig.) With 1 fig., 6 tabs., 24 refs.

  2. Antibacterial Activity of Diode Laser and Sodium Hypochlorite in Enterococcus Faecalis-Contaminated Root Canals.

    Science.gov (United States)

    Sohrabi, Khosrow; Sooratgar, Aidin; Zolfagharnasab, Kaveh; Kharazifard, Mohammad Javad; Afkhami, Farzaneh

    2016-01-01

    The aim of the present in vitro study was to evaluate the disinfection ability of 980-nm diode laser in comparison with sodium hypochlorite (NaOCl) as a common root canal irrigant in canals infected with Enterococcus faecalis (E. faecalis). The root canals of 18 extracted single-rooted premolars were prepared by rotary system. After decoronation, the roots were autoclaved. One specimen was chosen for the negative control, and the remaining teeth were incubated with E. faecalis suspension for two weeks. Subsequently, one specimen was selected as the positive control and the remaining samples were divided into two groups (n=8). The samples of the first group were irrigated with 5.25% NaOCl and the second group were treated with a 980-nm diode laser. Microbial samples were taken from the root canals and bacterial cultivation was carried out. The average value and the standard deviation of colony-forming units (CFU) of each specimen were measured using descriptive statistics. The student's t-test was used to compare the reduction in CFU in each group. The equality of variance of CFU was measured by the Levene's test. NaOCl resulted in 99.87% removal of the bacteria and showed significantly more antibacterial effect compared to the 980-nm diode laser which led to 96.56% bacterial reduction (Pdiode laser also reduced the bacterial count. Therefore a 980-nm diode laser could be considered as a complementary disinfection method in root canal treatment.

  3. Effect of ear canal pressure and age on wideband absorbance in young infants.

    Science.gov (United States)

    Aithal, Sreedevi; Aithal, Venkatesh; Kei, Joseph

    2017-05-01

    The study investigated the effect of ear canal pressure and age on wideband absorbance (WBA) in healthy young infants. Using a cross-sectional design, WBA at 0.25 to 8 kHz was obtained from infants as the ear canal pressure was swept from +200 to -300 daPa. The participants included 29 newborns, 9 infants each at 1 and 4 months and 11 infants at 6 months of age who passed distortion product otoacoustic emissions test. In general, negative-ear canal pressures reduced WBA across the frequency range, while positive-ear canal pressures resulted in reduced WBA from 0.25 to 2 kHz and above 4 kHz with an increase in absorbance between 2 and 3 kHz compared to WBA at ambient pressure. The variation in WBA below 0.5 kHz, as the pressure was varied, was the greatest in newborns. But, the variation was progressively reduced in older infants up to the age of 6 months, suggesting stiffening of the ear canal with age. Significant changes in WBA were observed as a function of pressure and age. In particular, developmental effects on WBA were evident during the first six months of life.

  4. Relation between proposed developments of water resources and seepage from the All-American Canal, eastern Imperial Valley, California

    Science.gov (United States)

    Loeltz, Omar J.; Leake, S.A.

    1979-01-01

    A two-layer digital model designed for this study indicated that sealing of the Coachella branch of the All-American Canal would cause an eventual increase in seepage from the All-American Canal of about 15,000 acre-feet annually. Sealing of both the Coachella Canal and the segment of the All-American Canal between Pilot Knob and Drop 1 would result in a lessening of seepage rates from the All-American Canal of 57,000 acre-feet in 1985, but of only 39,000 acre-feet in 2030. Sealing both the Coachella and the All-American Canals would reduce the outflow to Mexicali Valley from 120,000 acre-feet in 1980 to less than 9 ,000 acre-feet in 2030. The model also indicated that if only the Coachella Canal was sealed, a little less than 40% of water pumped from proposed well fields near the All-American Canal ultimately would be derived from increased seepage from the All-American Canal; between 50 and 60% of the water pumped would be water that otherwise would flow to Mexicali Valley. (USGS)

  5. Rivers: Nature's Wondrous Waterways.

    Science.gov (United States)

    Harrison, David L.

    Rivers play a vital role in the life of the planet. They provide water for wildlife, plant life, and people, and they help to fertilize fields where corn and other crops grow. But how were these rivers made? This children's book takes readers/students on a journey down a river from its source at the top of a mountain to its mouth where it meets…

  6. Visibility of the mandibular canal and the mental foramen in panoramic radiography

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Seon Jin; Choi, Eui Hwan; Kim, Jae Duk [Chosun Univ. School of Dentistry, Gwangju (Korea, Republic of)

    2001-09-15

    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.

  7. Root Canal Anatomy Visualization using Three-Dimensional Computed- Tomography and Transparent Preparation

    Directory of Open Access Journals (Sweden)

    Alexey V. Silin

    2013-09-01

    Full Text Available Three-dimensional Computed Tomography (CT is used to analyze the topography of the root canal anatomy in order to make a decision in choosing root canal preparation method. There is a method that make extracted teeth transparent maintaining its anatomical shape and size. It is important to compare the accuracy of the two visualization methods. Objective: To compare the transmission accuracy of root canals anatomy by two visualization methods, three-dimensional CT and transparent tooth preparation. Methods: Mandibular third molar was used as sample. The three-dimensional CT scan was performed before extracting the teeth. Then teeth were extracted and placed in solutions that made them transparent. Results: Despite the fact that the character of dental origin in terms of the angle of the crown, the curvature of the crown, the deviation of the root showed in three-dimensional CT, other tooth anatomical parameters were equally well detected using a transparent tooth preparation. Overall, the curvature of the root canals is more clearly shown by transparent tooth preparation. Conclusion: Transparent tooth preparation provides superior visualization of real root canal anatomy compared to three-dimensional CT, however the later could give us more information about the relation of the tooth within the jaw.DOI: 10.14693/jdi.v20i2.152

  8. Differences in cytotoxicity between 5% tetracycline hydrochloride and 15% EDTA as root canal irrigant

    Directory of Open Access Journals (Sweden)

    Devi Eka Juniarti

    2008-06-01

    Full Text Available 5% tetracycline hydrochloride and 15% EDTA as a root canal irrigant have been proven to be able to remove smear layer, open dentinal tubules and have antimicrobial activity. An effective root canal irrigation solution must be able to dissolve organic and anorganic debris, lubricate endodontic instruments, disinfect microorganism and non toxic. The purpose of this laboratory experimental study was to determine cytotoxicity differences between 5% tetracycline hydrochloride and 15% EDTA. 21 samples were used and classified into 3 groups: control, 5% tetracycline hydrochloride and 15% EDTA groups. Cytotoxicity test was done using BHK21 cells. The data was analyzed using Bird and Forrester formula. It concluded that 5% tetracycline hydrochloride more toxic than 15% EDTA as a root canal irrigant.

  9. Assessment of Root Canal Enlargement Using Mtwo and BioRace Rotary Files

    Directory of Open Access Journals (Sweden)

    Enzo Cumbo

    2015-01-01

    Full Text Available Objective. To evaluate root canal enlargement following mechanical shaping using 2 nickel titanium rotary systems. Material and Methods. Forty single-rooted teeth were immersed in resin and sectioned perpendicular to the long axis at 4, 8, and 12 mm from the apex. Digital capture of sections was performed before and after canal instrumentation using Mtwo and BioRace instruments. The area increase of endodontic space was calculated by subtraction. Results. The use of both instruments has allowed the removal of great amounts of dentin from the canal walls, even when the endodontic morphology is characterized by awkwardness to reach recesses. Conclusions. Both procedures seem to be valid and no differences were found between Mtwo and BioRaCe considering the amount of dentin removed at different distances from the apex.

  10. Meatoplasty in Canal wall down Surgery: Our Experience and Literature Review

    Directory of Open Access Journals (Sweden)

    Faramarz Memari

    2017-01-01

    Full Text Available Introduction: Meatoplasty is the final and essential step in performing effective canal wall down surgery for chronic otitis media. In this article we review some previous techniques and discuss our preferred method. Materials and Methods: In this observational case series study, we used this technique in 53 patients (28 male and 25 female between January 2005 and January 2008. Our survey was completed in 31 patients. Results: Twenty-six patients (83.9% said their ear appeared normal after the procedure, but five patients (16.1% complained of some minor change in the shape of their ear. Twenty-nine patients (93.5% had a completely wide ear canal. The ear canal had some degree of stenosis in two patients (6.5% post-operatively. Conclusion: This technique offers good functional and cosmetic results with minimal manipulation and minimal anatomic disruption.

  11. Mandibular second molar with 3 mesial canals and a radix paramolaris

    Directory of Open Access Journals (Sweden)

    N Ragavendran

    2014-01-01

    Full Text Available Mandibular first molar commonly has two roots, the mesial and the distal root. Surprisingly in some mandibular first molar has an unusual extra third root in between mesial and distal root. This extra root is the most commonly seen in lingual side and is called as radix entomolaris. If this extra root is seen on the buccal side, it is termed as radix paramolaris (RP, which is a very rare phenomenon. Recently, various case report studies has shown the presence of third canal in the mesial and distal roots of mandibular molars. They are named as middle mesial and middle distal canal, respectively. Here, we present a case report of mandibular second molar showing three canals in the mesial root and a RP.

  12. Meatoplasty in Canal wall down Surgery: Our Experience and Literature Review.

    Science.gov (United States)

    Memari, Faramarz; Maleki Delarestaghi, Mojtaba; Mir, Parisa; GolMohammadi, Mohammad; Shams Koushki, Ehsan

    2017-01-01

    Meatoplasty is the final and essential step in performing effective canal wall down surgery for chronic otitis media. In this article we review some previous techniques and discuss our preferred method. In this observational case series study, we used this technique in 53 patients (28 male and 25 female) between January 2005 and January 2008. Our survey was completed in 31 patients. Twenty-six patients (83.9%) said their ear appeared normal after the procedure, but five patients (16.1%) complained of some minor change in the shape of their ear. Twenty-nine patients (93.5%) had a completely wide ear canal. The ear canal had some degree of stenosis in two patients (6.5%) post-operatively. This technique offers good functional and cosmetic results with minimal manipulation and minimal anatomic disruption.

  13. Waterways of Hope | IDRC - International Development Research ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-12-15

    Dec 15, 2010 ... A number of community members and four young hired workers from the oasis used self-made tools of welded iron scraps for levelling. Once completed, a construction company from Farafra was hired to pour the canal's concrete foundation. The brick work was subsequently completed by a local contractor.

  14. Diagnostic value of saccoradiculography and of cat scan to detect stenosis of the lumbar canal

    Energy Technology Data Exchange (ETDEWEB)

    Arrault, I.; Benoist, M.; Rocolle, J.; Busson, J.; Lassale, B.; Deburge, A.

    1987-10-01

    Radiculographic X-rays and CAT scans of 60 patients operated on for stenosis of the lumbar canal were analysed separately and retrospectively by rheumatologists, a radiologist and surgeons working jointly, without knowledge of findings revealed by surgery. Comparison of findings with a detailed surgical report reveals that in the case of central lumbar canal stenosis, CAT scan provides a higher degree of reliability (72%) in diagnosis than does radiculography (56%). With lateral stenosis of the lateral cleft, reliability of both tests is identical (62%). The diagnostic deficiencies of these two examinations are discussed as well as diagnostic criteria employed and possible avenues of research. Currently, in the case of stenosis of the lumbar canal, it is still necessary to perform both of these examinations in combination and to accept the fact that, in certain cases, only one of the two tests reveals the stenosis, to be able to attain a preoperative rate of correct diagnosis greater than 80%.

  15. Computed tomography in lumbar canal stenosis. Relationship between its findings and clinical symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Shu; Baba, Itsushi; Ishida, Akihisa; Sumida, Tadayuki; Sasaki, Seishu (Hiroshima Shiritsu Asa Shimin Hospital (Japan))

    1984-09-01

    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.

  16. Magmatic evolution of Panama Canal volcanic rocks: A record of arc processes and tectonic change.

    Science.gov (United States)

    Farris, David W; Cardona, Agustin; Montes, Camilo; Foster, David; Jaramillo, Carlos

    2017-01-01

    Volcanic rocks along the Panama Canal present a world-class opportunity to examine the relationship between arc magmatism, tectonic forcing, wet and dry magmas, and volcanic structures. Major and trace element geochemistry of Canal volcanic rocks indicate a significant petrologic transition at 21-25 Ma. Oligocene Bas Obispo Fm. rocks have large negative Nb-Ta anomalies, low HREE, fluid mobile element enrichments, a THI of 0.88, and a H2Ocalc of >3 wt. %. In contrast, the Miocene Pedro Miguel and Late Basalt Fm. exhibit reduced Nb-Ta anomalies, flattened REE curves, depleted fluid mobile elements, a THI of 1.45, a H2Ocalc of rocks indicates 0.5-0.1 kbar crystallization depths of hot (1100-1190°C) magmas in which most compositional diversity can be explained by fractional crystallization (F = 0.5). However, the most silicic lavas (Las Cascadas Fm.) require an additional mechanism, and assimilation-fractional-crystallization can reproduce observed compositions at reasonable melt fractions. The Canal volcanic rocks, therefore, change from hydrous basaltic pyroclastic deposits typical of mantle-wedge-derived magmas, to hot, dry bi-modal magmatism at the Oligocene-Miocene boundary. We suggest the primary reason for the change is onset of arc perpendicular extension localized to central Panama. High-resolution mapping along the Panama Canal has revealed a sequence of inward dipping maar-diatreme pyroclastic pipes, large basaltic sills, and bedded silicic ignimbrites and tuff deposits. These volcanic bodies intrude into the sedimentary Canal Basin and are cut by normal and subsequently strike-slip faults. Such pyroclastic pipes and basaltic sills are most common in extensional arc and large igneous province environments. Overall, the change in volcanic edifice form and geochemistry are related to onset of arc perpendicular extension, and are consistent with the idea that Panama arc crust fractured during collision with South America forming the observed Canal extensional

  17. Root and canal symmetry in the mandibular anterior teeth of patients attending a dental clinic: CBCT study.

    Science.gov (United States)

    Kayaoglu, Guven; Peker, Ilkay; Gumusok, Mustafa; Sarikir, Cigdem; Kayadugun, Aylin; Ucok, Ozlem

    2015-01-01

    The aims of this study were to evaluate the number of roots/root canals in the mandibular anterior teeth of a Turkish population, to assess the relationship between gender or age and the frequency of two canals in a single root, and to determine the symmetry in root/root canal numbers between contralateral sides among patients. Cone-beam computed tomography images (n = 1128; 6253 teeth) taken at the Department of Dentomaxillofacial Radiology of the Faculty of Dentistry of Gazi University were examined by three observers and a supervisor, all of whom were blinded to patient gender and age. Axial, sagittal, and cross-sectional slices with a thickness of 1 mm were used. Numbers of roots and canals for each type of tooth were recorded. Most teeth had a single root and single root canal. Roots with two canals were more frequent in the incisors (14.9%, 17.2%, and 6.1% of the central incisors, lateral incisors, and canines, respectively). Teeth with two roots were more frequent in the canines (3.1% vs. 0% or 0.1%). Females more often had canines with double root canals (p symmetry between contralateral teeth was found in 45.0%, 29.0%, and 28.0% of cases for central incisors, lateral incisors, and canines, respectively. Patients older than 56 years had fewer teeth with double root canals (p ≤ 0.001). A small proportion of the mandibular anterior teeth had two roots or root canals. Double root canals were mostly unilateral. Age and gender were associated with the number of root canals.

  18. Concurrent Effects of Bleaching Materials and the Size of Root Canal Preparation on Cervical Dentin Microhardness.

    Science.gov (United States)

    Kazemipoor, Maryam; Azad, Shaghayegh; Farahat, Farnaz

    2017-01-01

    The aim of the present study was to evaluate the concurrent effect of root canal preparation size and intra coronal bleaching on dentin microhardness. Seventy-two intact anterior teeth were root canal treated and randomly divided into two groups (n=36) according to the size of coronal root canal preparation. The coronal portions of the canals were then enlarged with #2 and 4 Peeso reamers, respectively. Following root canal obturation, teeth were assigned into three groups (n=12) to be treated with bleaching agents containing 35% hydrogen peroxide (HP), sodium perborate (SP) and distilled water as control group. The teeth were stored at 37(º)C and 100% humidity for 7 days. Dentinal blocks with 3 mm thickness were obtained from the cervical region and Vickers microhardness number (VHN) were measured for outer and inner dentin in each tooth sample. Data were analyzed using two-way ANOVA and Tukey's HSD tests. In the outer dentin, the mean VHN in the HP and control groups showed statistically significant differences (P=0.047). The mean VHN of inner dentin for the large preparation size was statistically higher in comparison to the small preparation size (P=0.042). There was a statistically significant difference in the mean VHN of inner dentin with small preparation size between HP and SP groups (P=0.029) and HP and control groups (P=0.021). Intra coronal bleaching with 35% hydrogen peroxide, affects the inner and outer dentin significantly. Excessive removal of cervical dentin, following root canal preparation, alongside the adverse effect of bleaching materials on dentin could result in the tooth fracture.

  19. Using QUAL2K Model and river pollution index for water quality management in Mahmoudia Canal, Egypt

    Directory of Open Access Journals (Sweden)

    Ehab A. Elsayed

    2014-08-01

    Full Text Available The Mahmoudia Canal is the main source of municipal and industrial water supply for Alexandria (the second largest city in Egypt and many other towns and villages. In recent years, considerable water quality degradation has been observed in the Mahmoudia Canal. This problem has attracted increasing attention from both the public and the Egyptian government. As a result, this study aims at assessing the current seasonal variations in water quality in the Mahmoudia Canal and simulating various water quality management scenarios for the canal. The present research involves the application of the water quality model, QUAL2K, to predict water quality along the Mahmoudia Canal on a seasonal basis for the considered scenarios. Based on the QUAL2K simulations, the River Pollution Index (RPI was used to appraise the conditions of water pollution at the intakes of the twelve water treatment plants (WTPs located along Mahmoudia Canal. The results showed that the QUAL2K model is successfully applied to simulate the water quantity and quality parameters of the Mahmoudia Canal in different seasons. For the current status of the canal, it was found that the highest pollution level occurred in autumn in which effluent water quality at all WTPs along the Mahmoudia Canal was classified as moderately polluted. In the other seasons, effluent water quality was categorized as moderately polluted at most WTPs in the Beheira governorate and negligibly polluted at all WTPs in the Alexandria governorate. Moreover, it was concluded that controlling the Rahawy drain discharge or treating its pollution loads before mixing with the Rosetta Branch may solve water quality problems of the Mahmoudia Canal and allow re-running of the Edko re-use pump station in summer, winter, and spring. However in autumn, additional measures will be required to mitigate pollution levels in the canal.

  20. Evaluation of the apical infiltration after root canal disruption and obturation

    Directory of Open Access Journals (Sweden)

    João Eduardo Gomes-Filho

    2008-10-01

    Full Text Available The aim of this study was to evaluate two root canal filling techniques used in teeth that had their apical foramen disrupted and compare the apical infiltration with an ideal clinical situation. Twenty-seven freshly extracted single-rooted teeth were selected and radiographed to confirm the existence of a single and straight root canal. The crowns were removed at a mean distance of 11 mm from the apex. The teeth had the root canals instrumented and were randomly assigned to 3 groups (n=9: ND group - root canals were filled using the lateral compaction technique and no disruption was performed; DRF group - the apical constriction was disrupted by advancing a #40 K-file 1 mm beyond the original working length, the canals were reinstrumented to create an apical ledge at 1 mm from the apical foramen and were obturated with a master gutta-percha cone with same size as the last file used for reinstrumentation; DF group - the teeth had the apical constriction disrupted and the canals were obturated with a master gutta-percha cone that fit at 1 mm from the apex. The teeth were submitted to dye leakage test with Rhodamine B for 7 days, using vaccum on the initial 5 min. The teeth were sectioned longitudinally and the leakage was measured in a linear fashion from apex to crown. There was no statistically significant difference (p>0.05 between the groups that had the apical foramen disrupted (DF, DRF, but significant difference was found between the disrupted groups and the non-disrupted one (p<0.01. In conclusion, none of the evaluated techniques was able to prevent apical infiltration, so working length so the working length determination has to be established and maintained carefully.

  1. The position of the mandibular canal and histologic feature of the inferior alveolar nerve.

    Science.gov (United States)

    Kilic, C; Kamburoğlu, K; Ozen, T; Balcioglu, H A; Kurt, B; Kutoglu, T; Ozan, H

    2010-01-01

    The inferior alveolar nerve is the one of the large branches of the mandibular division of the trigeminal nerve. It is vulnerable during surgical procedures of the mandible. Despite its importance, no anatomical and histological examination has been conducted to provide a detailed cross-sectional morphology of the mandibular canal according to dental status. Therefore, the present study aimed to identify the position of the mandibular canal through direct measurement and to determine the branches of the inferior alveolar nerve through histologic examination. The area between the anterior margin of the third molar and the anterior margin of the second premolar of dentulous, partially dentulous, and edentulous hemimandible specimens (n = 49) from 26 human cadavers was serially sectioned into seven segments, and specific distances were measured using digital calipers. Following this, 5-microm cross-sections were prepared along the mandibular canal and mental foramen, and examined by fluorescence microscopy. The mandibular canal was located at a mean distance of 10.52 mm above the inferior margin of the mandible. The mean maximum diameters of the mandibular canal, inferior alveolar nerve, inferior alveolar artery, and inferior alveolar vein were 2.52, 1.84, 0.42, and 0.58 mm, respectively. This study found that the inferior alveolar nerve often gives rise to several branches at each level (range 0-3). To minimize the risk of injury, knowledge of the small branches of the nerve and of the detailed findings regarding the position of the mandibular canal reported here should be considered when planning mandibular surgery, especially during implant placement.

  2. Chlorhexidine as a root canal irrigant: Antimicrobial and scanning electron microscopic evaluation

    Directory of Open Access Journals (Sweden)

    Živković Slavoljub

    2010-01-01

    Full Text Available Introduction. Selection of irrigant is very important for longterm success of root canal therapy. Objective. This study was undertaken to evaluate the antimicrobial effects of 2% chlorhexidine digluconate solution (CHX against five selected microorganisms and to evaluate its efficacy in root canal cleaning. Methods. In this study, by agar diffusion test, were evaluated antimicrobial effects of three root canal irrigants: 5.25% NaOCl, 2.5% NaOCl and 2% CHX. The microorganisms tested in this study were Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis, Escherichia coli and Candida albicans. A scanning electron microscope was used to evaluate root canal cleaning ability of 5.25% NaOCl, 2.5% NaOCl, 2% CHX and 15% EDTA. Twelve extracted single-root human teeth were divided into four groups depending on the irrigant used during instrumentation. Mechanical preparation was performed with Step back technique and K files. Data were analyzed statistically by Student’s t-test. Results 5.25% NaOCl was the most effective against all tested microorganisms. 2.5% NaOCl and 2% CHX showed antimicrobial effects against all tested microorganisms but zones of inhibition were smaller. The best results in root canal walls cleaning were obtained in the group where the irrigant was 15% EDTA (score 2.33. In 5.25% NaOCl, 2.5% NaOCl and 2% CHX groups, there was more smear layer (score 4 and 5. Conclusion. 2% chlorhexidine digluconate showed strong antimicrobial effect on the tested microorganisms, but was not effective in cleaning root canal walls.

  3. Relationship of the Gonial Angle and Inferior Alveolar Canal Course Using Cone Beam Computed Tomography

    Directory of Open Access Journals (Sweden)

    Najmeh Anbiaee

    2016-03-01

    Full Text Available Objectives: Accurate localization of the inferior alveolar canal (IAC is extremely important in some dental treatments. Anatomical variation of the canal means that it can be difficult to locate. The purpose of this study was to assess the relationship of the gonial angle (GA size and IAC position using cone beam computed tomography (CBCT.Materials and Methods: In this in vitro study, 61 dry adult human hemi-mandibles were used. The CBCT scans were taken of all samples and GA was measured on all CBCT scans. The samples were divided into two groups of low angle (≤125° and high angle (>125°. The canal dimensions, length and course were evaluated. On the sagittal view, the IAC path was classified as type A, B or C. On the axial view, canal course was defined as A1 or A2 according to the mental foramen angle.Results: The average GA size was 121.8±7.05° at the right side and 123.8±6.32° at the left side. On the sagittal view, there was a significant correlation between the GA size and the canal course (P=0.04. In the high-angle group, type A was dominant; whereas in the low-angle group, type B was more common. On the axial view of IAC course, type A1 was more common (73.43%.Conclusion: The results showed that GA size was associated with IAC course. In cases with a larger GA, the canal runs in a more straightforward path, and at the same level as the mental foramen.Keywords: Cone Beam Computed Tomography; Mandibular Nerve; Mandible

  4. The dimensions of the tarsal sinus and canal in different foot positions and its clinical implications

    NARCIS (Netherlands)

    Kleipool, R. P.; Blankevoort, L.; Ruijter, J. M.; Kerkhoffs, G. M. M. J.; Oostra, R. J.

    2017-01-01

    This study presents a reference for the dimensions of the tarsal sinus and canal in healthy adults in different foot positions to facilitate understanding of the kinematics of the subtalar joint, the effect of an implant, and other clinical issues. In a 3D CT stress test on 20 subjects, the right

  5. Identification of dental root canals and their medial line from micro-CT and cone-beam CT records.

    Science.gov (United States)

    Benyó, Balázs

    2012-10-29

    Shape of the dental root canal is highly patient specific. Automated identification methods of the medial line of dental root canals and the reproduction of their 3D shape can be beneficial for planning endodontic interventions as severely curved root canals or multi-rooted teeth may pose treatment challenges. Accurate shape information of the root canals may also be used by manufacturers of endodontic instruments in order to make more efficient clinical tools. Novel image processing procedures dedicated to the automated detection of the medial axis of the root canal from dental micro-CT and cone-beam CT records are developed. For micro-CT, the 3D model of the root canal is built up from several hundred parallel cross sections, using image enhancement, histogram based fuzzy c-means clustering, center point detection in the segmented slice, three dimensional inner surface reconstruction, and potential field driven curve skeleton extraction in three dimensions. Cone-beam CT records are processed with image enhancement filters and fuzzy chain based regional segmentation, followed by the reconstruction of the root canal surface and detecting its skeleton via a mesh contraction algorithm. The proposed medial line identification and root canal detection algorithms are validated on clinical data sets. 25 micro-CT and 36 cone-beam-CT records are used in the validation procedure. The overall success rate of the automatic dental root canal identification was about 92% in both procedures. The algorithms proved to be accurate enough for endodontic therapy planning. Accurate medial line identification and shape detection algorithms of dental root canal have been developed. Different procedures are defined for micro-CT and cone-beam CT records. The automated execution of the subsequent processing steps allows easy application of the algorithms in the dental care. The output data of the image processing procedures is suitable for mathematical modeling of the central line. The

  6. Ectopic external auditory canal and ossicular formation in the oculo-auriculo-vertebral spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Supakul, Nucharin [Indiana University School of Medicine, Department of Radiology, Indianapolis, IN (United States); Ramathibodi Hospital, Mahidol University, Department of Diagnostic and Therapeutic Radiology, Bangkok (Thailand); Kralik, Stephen F. [Indiana University School of Medicine, Department of Radiology, Indianapolis, IN (United States); Ho, Chang Y. [Indiana University School of Medicine, Department of Radiology, Indianapolis, IN (United States); Riley Children' s Hospital, MRI Department, Indianapolis, IN (United States)

    2015-07-15

    Ear abnormalities in oculo-auricular-vertebral spectrum commonly present with varying degrees of external and middle ear atresias, usually in the expected locations of the temporal bone and associated soft tissues, without ectopia of the external auditory canal. We present the unique imaging of a 4-year-old girl with right hemifacial microsomia and ectopic location of an atretic external auditory canal, terminating in a hypoplastic temporomandibular joint containing bony structures with the appearance of auditory ossicles. This finding suggests an early embryological dysfunction involving Meckel's cartilage of the first branchial arch. (orig.)

  7. Building and Testing a Statistical Shape Model of the Human Ear Canal

    DEFF Research Database (Denmark)

    Paulsen, Rasmus Reinhold; Larsen, Rasmus; Laugesen, Søren

    2002-01-01

    on a training set of laser scanned ear impressions and a sparse set of anatomical landmarks placed by an expert. The landmarks are used to warp a template mesh onto all shapes in the training set. Using the vertices from the warped meshes, a 3D point distribution model is made. The model is used for testing......Today the design of custom in-the-ear hearing aids is based on personal experience and skills and not on a systematic description of the variation of the shape of the ear canal. In this paper it is described how a dense surface point distribution model of the human ear canal is built based...

  8. Cutaneous Neuroendocrine Carcinoma of the External Auditory Canal: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Yi-Ke Li

    2012-01-01

    Full Text Available Cutaneous neuroendocrine carcinoma (cNEC is rarely seen in the external ear. In this paper, we newly describe a patient with cNEC in his right external auditory canal, followed by a further discussion on the clinical features, diagnosis, and treatments of cNEC of the external ear. A review of the literature showed that cNEC of the external auditory canal generally presents as asymptomatic and that pathology yields the most confirmative diagnosis. A wide resection with adjuvant radiotherapy and chemotherapy is recommended. The overall prognosis of this condition is poor.

  9. Comparative analysis of root canal instrumentation using protaper gold, waveone gold and k-files

    OpenAIRE

    Basso, Ivana Gradicek Fraústo

    2016-01-01

    Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2016 INTRODUCTION: The major goals of endodontic treatment is to preserve the functinal teeth, by removing from the root canal system; obturate the cleaned and shaped system; and prevent future recontamination of sealed root canals. AIMS: The purpose of this study is to compare 3D measures between three different systems; manual instrumentation with K-Filesand two rotary files: ProTaper GoldTM and ...

  10. Clinical Anatomy and Significance of the Retromolar Foramina and Their Canals: A Literature Review.

    Science.gov (United States)

    Truong, Mindy K; He, Puhan; Adeeb, Nimer; Oskouian, Rod J; Tubbs, R Shane; Iwanaga, Joe

    2017-10-17

    The retromolar foramina (RMF) and the retromolar canal (RMC) are anatomic variants in the mandible located distally to the last molar. The retromolar nerve, which runs through the RMC, is a type 1 bifidity of the mandibular canal. The investigations of the RMF and RMC have been performed by dry mandible studies, the panoramic radiograph (PAN), computed tomography (CT), and the cone beam computed tomography (CBCT) studies. The CBCT has been shown to be the superior method for visualizing the RMF and RMC. There is wide variation in the frequency, location, diameter, and distance of the canal in different individuals. Overall, there is no significant difference in the frequency of the canal in the mandible between sexes or sides of the mandible. The peak incidence of the RMF may occur in adolescence. The RMC is significant due to the neurovascular bundle which runs through it. Injury to this neurovascular bundle during surgical procedures, such as third molar extraction, implant placement, or split sagittal osteotomy, may lead to paresthesia, excessive bleeding, or traumatic neuroma. The presence of RMC may also lead to insufficient anesthesia in the mandible which may be overcome with alternative anesthetic techniques.

  11. Comparative evaluation of myeloscintigraphy and radiological contrast examinations of the vertebral canal

    Energy Technology Data Exchange (ETDEWEB)

    Popiolek, A.; Wasylewski, A. (Slaska Akademia Medyczna, Katowice (Poland))

    In a group of 21 cases the authors compared these two methods for assessing their usefulness for the diagnosis of spinal diseases located in the vertebral canal. The analysed material included 22 myeloscintigraphic examinations and 18 radiological myelographies. In 4 cases of obliterative arachnoiditis myeloscintigraphy demonstrated presence of pathological process, while Myodil myelography gave in these cases false negative results. Myeloscintigraphy is a valuable auxiliary investigation causing little discomfort to the patient and is helpful in the diagnosis of different pathological processes in the vertebral canal. The method was found to be particularly superior to myelography done with heavy contrast media in the diagnosis of obliterative aeachnoiditis.

  12. Root Canal Morphology of Permanent Maxillary and Mandibular Canines in Indian Population Using Cone Beam Computed Tomography

    Directory of Open Access Journals (Sweden)

    Nikhita Somalinga Amardeep

    2014-01-01

    Full Text Available Aim. To investigate the root canal anatomy of single-rooted permanent maxillary and mandibular canines in an Indian population using cone beam computed tomography (CBCT. Methodology. A total of 250 permanent maxillary canines and 250 permanent mandibular canines were selected and scanned using CBCT. The root anatomy of each tooth was evaluated for the following parameters: the pattern of the root canals, anatomic length of the crown and the root, the presence of accessory canals, the shape of the access cavity, the position of the apical foramina, root diameter, and dentin thickness of the root. Results. Majority of the teeth had a Type I canal configuration in both maxillary canines (81.6% and mandibular canines (79.6%. In maxillary canine the other canal patterns found were Type III (11.6%, Type II (2.8%, Type V (2%, Type XIX (1.2%, and Type IV (0.8%. In mandibular canines the various other canal patterns found were Type III (13.6%, Type II (3.2%, Type V (2%, and Type XIX (1.6%. Apical foramina were laterally positioned in the majority of the teeth, 70.4% and 65.6% in maxillary and mandibular canines, respectively. 12% of the maxillary canines and 12.8% of the mandibular canines had accessory canals. Conclusion. The root canal anatomy of permanent maxillary and mandibular canines varied widely in an Indian population.

  13. Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

    Science.gov (United States)

    Boyer, Doug M; Kirk, E Christopher; Silcox, Mary T; Gunnell, Gregg F; Gilbert, Christopher C; Yapuncich, Gabriel S; Allen, Kari L; Welch, Emma; Bloch, Jonathan I; Gonzales, Lauren A; Kay, Richard F; Seiffert, Erik R

    2016-08-01

    Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic

  14. Laser Induced Explosive Vapor and Cavitation Resulting in Effective Irrigation of the Root Canal. Part 2 : Evaluation of the Efficacy

    NARCIS (Netherlands)

    De Moor, Roeland Jozef Gentil; Blanken, Jan; Meire, Maarten; Verdaasdonk, Rudolf

    Background and Objectives: Limited information exists regarding the efficacy of laser activated irrigation (LAI) on removal of root canal debris. This study compares the efficacy of LAI for removal of debris in root canals as compared to conventional irrigation (CI) and passive ultrasonic irrigation

  15. [Comparison of antimicrobial activity of Er,Cr: YSGG laser and ultrasonic irrigation in root canal disinfection].

    Science.gov (United States)

    Lu, Chun-Hui; Zhong, Qun

    2017-06-01

    The aim of this study was to compare the antimicrobial activity of Er,Cr:YSGG laser and ultrasonic irrigation in root canal disinfection. Sixty decayed teeth requiring root canal therapy were divided into 3 groups randomly: Er,Cr:YSGG laser group, ultrasonic irrigation group and control group, 20 in each group. The bacteria in each group were incubated and counted before and after root canal treatment. Statistical analysis was performed using SPSS 19.0 software package. In the 3 groups, the number of bacteria in root canals was reduced significantly after root canal treatment (PCr:YSGG laser group and ultrasonic irrigation group decreased significantly greater than the control group (PCr:YSGG laser group and ultrasonic irrigation group had no significant difference(P>0.05). After root canal treatment, the number of bacteria in the root canal is obviously reduced. The antimicrobial activity of three intercanal methods on bacteria in root canals is profound. The reduction of bacteria is more obvious after treatment of Er,Cr:YSGG laser and ultrasonic irrigation than the control.

  16. Ultrastructure, functional morphology and evolution of recto-canal epidermal glands in Myriapoda.

    Science.gov (United States)

    Müller, Carsten H G; Rosenberg, Jörg; Hilken, Gero

    2014-01-01

    In Chilopoda, solitary epidermal glands are composed of a couple of cells only. These glands are highly abundant on the entire body surface and are distributed throughout the single-layered epidermis. Some authors provided more or less comprehensive observations on the structure of epidermal glands of specific chilopod taxa. However, no information is hitherto available on the ultrastructural diversity of these glands. Furthermore, potential homologies of these chilopod epidermal glands and of their characteristic cellular components remain unknown. Based on our results, we are now able to distinguish two types of epidermal glands in Chilopoda that can be clearly distinguished by their structure and the course of their conducting canal: recto-canal epidermal glands (rceg) and flexo-canal epidermal glands (fceg). In the present paper, we focus on the rceg. We examined the ultrastructural organization of these glands in the head region and on the anterior trunk segments of various representatives of the five extant chilopod orders by light- and electron-microscopy. According to our terminology, rceg consist of up to five different cell types including: a) distal canal cells, b) proximal canal cells, c) intermediary cells, and d) two different types of secretory cells. Intermediary and canal cells form a common conducting canal. The rceg may taxon-specifically differ in relative size and subcellular architecture, but all have the following features in common: 1) a wide distribution on various body regions among all five chilopod subtaxa, 2) the straight, broad and locally dilated conducting canal surrounded by closely packed microvilli or microvilliform infoldings around the apex of the canal cell(s), and 3) the tendency to aggregate to form compound glandular organs of massive size and complexity. Tricellular glandular units established by three different cell types are observed in Scutigeromorpha and Geophilomorpha, whereas four cell types constitute rceg in

  17. Definition and endodontic treatment of dilacerated canals: a survey of Diplomates of the American Board of Endodontics.

    Science.gov (United States)

    Dastmalchi, Nafiseh; Kazemi, Zeinab; Hashemi, Siroos; Peters, Ove A; Jafarzadeh, Hamid

    2011-01-01

    To gather data from Diplomates of the American Board of Endodontics regarding treatment of dilacerated canals. A questionnaire addressing definition, endodontic treatment procedures and prognosis was constructed and distributed via e-mail to 708 Diplomates of the American Board of Endodontics. Data from 150 respondents, a 21% response rate, were collected by using a Web-based interface. For statistical analysis, Chi-square tests were used. More than 25% of respondents believed that a dilacerated root should have a curvature > 40°. One-visit treatment is the best therapeutic approach and transportation is the most likely complication in preparation of these canals. A crown-down technique, watch-winding motion and a master apical file # 25 are the best choices for preparation of these canals. Any warm obturation technique is preferred over lateral compaction by most respondents. A crown-down technique for root canal preparation and a thermoplastic obturation technique are recommended for canals whose curvature is more than 40°. The prognosis of the treatment of these canals is judged not lower than normal canals. Crown-down technique and thermoplastic obturation are recommended for dilacerated canals.

  18. The root canal shaping ability of WaveOne and Reciproc versus ProTaper Universal and Mtwo rotary NiTi systems

    Directory of Open Access Journals (Sweden)

    Ahmed S Abu Haimed

    2017-01-01

    Conclusions: Continuous rotation and reciprocating files were safe and maintained the original canal anatomy. However, continuous rotation instruments have a higher tendency for canals transportation and aberrations, especially with larger curvatures. Reciprocating files were faster than continuous rotation files in shaping simulated root canals in resin blocks.

  19. Waterways – ways of value : Planning for redevelopment of an ageing system in modern society

    NARCIS (Netherlands)

    Hijdra, Arjan

    2017-01-01

    Historically, many western countries developed networks of navigable waterways to serve their transportation needs. Today these networks face a threefold challenge: assets like navigation locks, weirs and bridges are ageing, climate change influences operational circumstances, and society calls for

  20. Children's Health Curriculum Lesson 6: Keeping All of Our Waterways Clean

    Science.gov (United States)

    This lesson helps kids understand the importance of water in our lives and describes the life cycle of freshwater. It also discusses how to keep trash from getting in storm drains and polluting our waterways.

  1. Correlation of panoramic radiographs and cone beam computed tomography in the assessment of a superimposed relationship between the mandibular canal and impacted third molars

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yun Hoa; Nah, Kyung Soo; Cho, Bong Hae [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Pusan National University, Yangsan (Korea, Republic of)

    2012-09-15

    This study evaluated the association between cone beam computed tomography (CBCT) and panoramic radiographs in the assessment of a superimposed relationship between the mandibular canal and impacted third molars. The study samples consisted of 175 impacted third molars from 131 patients who showed a superimposed relationship between the mandibular canal and third molars on panoramic radiographs and were referred for the examination of the mandibular canal with CBCT. Panoramic images were evaluated for the darkening of the root and the interruption of the mandibular canal wall. CBCT images were used to assess the buccolingual position of the mandibular canal relative to the third molar, the proximity of the roots to the canal, and lingual cortical bone loss. The association of the panoramic and CBCT findings was examined using a Chi-square test and Fisher's exact test. Panoramic radiographic signs were statistically associated with CBCT findings (P<0.01). In cases of darkening roots, lingual cortical bone loss or buccally positioned canals were more frequent. In cases in which the mandibular canal wall was interrupted on panoramic radiographs, contact or lingually positioned canals were more frequent. The results of this study suggest that contact between the mandibular third molar and canal and a lingually positioned canal could be more frequently observed in cases of the interruption of the white line of the mandibular canal and that there could be more lingual cortical loss in cases of darkening roots.

  2. Endodontic Treatment of the Mandibular First Molar with Six Roots Canals – Two Case Reports and Literature Review

    Science.gov (United States)

    Anderson, Craig

    2015-01-01

    The most common configuration of the mandibular first molar is the presence of two roots and three root canals. The objective of this work is to present two rare anatomic configurations with six root canals on two mandibular left first molars diagnosed during endodontic therapy. Root canal therapy was performed using a dental operating microscope. Ultrasonic troughing in the grooves in between the mesial root canals and in between the distal root canals was able to show the middle root canals. Large samples population characterization researches and systematic reviews were unable to detect a single case of six root canals configuration in a mandibular first molar in their investigations. Although it is a rare configuration, a six root canal configuration is possible to be found in the mandibular first molar. Three different pulp chamber configurations are possible to be found. Two or three roots may be present and the root configuration more common in the mesial root is the Type 8 and Type 12 for the distal root. Some concepts about the required technique to approach these cases are also debated. PMID:26023651

  3. [Endodontics in motion: new concepts, materials and techniques 3. The role of irrigants during root canal treatment].

    Science.gov (United States)

    van der Sluis, L W M

    2015-10-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm) and their products from the root canal wall, their removal out of the root canal system and their chemical dissolution or disruption. Each of the endodontic irrigation systems has its own irrigant flow characteristics, which should fulfill these aims. Without flow (convection), the irrigant would have to be distributed through diffusion. This process is slow and depends on temperature and concentration gradients. On the other hand, convection is a faster and more efficient transport mechanism. During irrigant flow, frictional forces will occur, for example between the irrigant and the root canal wall (wall shear stress). These frictional forces have a mechanical cleaning effect on the root canal wall. These frictional forces are the result of the flow characteristics related to the different irrigation systems.

  4. The ability of cone-beam computed tomography to detect simulated buccal and lingual recesses in root canals

    NARCIS (Netherlands)

    Liang, Y.H.; Yuan, M.; Li, G.; Shemesh, H.; Wesselink, P.R.; Wu, M.K.

    2012-01-01

    Aim  To compare the ability of cone-beam computed tomography (CBCT) and digital periapical radiographs (PR) to detect simulated tissue-occupied recesses in root canals. Methodology  A standard canal was created in 30 extracted mandibular premolar roots. Each root was longitudinally split into buccal

  5. Use of ImageJ software for histomorphometric evaluation of normal and severely affected canine ear canals.

    Science.gov (United States)

    Zur, Gila; Klement, Eyal

    2015-10-01

    Morphological studies comparing normal and diseased ear canals use primarily subjective scoring. The aim of this study was to compare normal and severely affected ears in dogs with objective measurements using ImageJ software. Ear canals were harvested from cadavers with normal ears and from dogs that underwent total ear canal ablation for unresolved otitis. Histopathology samples from ear canals were evaluated by semi-quantitative scoring and also by using ImageJ-software for histomorphometric measurements. The normal ears were compared to the severely affected ears using the 2 methods. The 2 methods were significantly (P otitis externa and that ImageJ software can be efficiently used to measure and evaluate ear canal histomorphometry.

  6. Rehabilitation options for inland waterways impacted by sulfidic sediments--a synthesis.

    Science.gov (United States)

    Baldwin, Darren S; Fraser, Mark

    2009-01-01

    The build up of reduced inorganic sulfur in the sediments of inland wetlands and creeks is an emerging risk for the management of inland waterways and is a direct result of secondary salinisation. Inappropriate management of these sediments can lead to a number of adverse environmental outcomes, the most dramatic of which is the extreme acidification of inland waterways, but can also include deoxygenation and the release of heavy metals. This paper explores possible management options for reducing the impact of sulfidic sediments on inland waterways based on previous research into ameliorating the impact of acid mine and acid rock drainage and coastal acid sulfate soils. The main strategies explored include minimising the formation of sulfidic sediments in the first instance, rehabilitation of impacted waterways, or isolation of the water body from the surrounding environment.

  7. Canal plane dynamic visual acuity in superior canal dehiscence.

    Science.gov (United States)

    Janky, Kristen L; Zuniga, M Geraldine; Ward, Bryan; Carey, John P; Schubert, Michael C

    2014-06-01

    1) To characterize normal, horizontal active dynamic visual acuity (DVA) and passive canal plane head thrust DVA (htDVA) across ages to establish appropriate control data and 2) to determine whether horizontal active DVA and passive canal plane htDVA are significantly different in individuals with superior canal dehiscence syndrome (SCDS) before and after surgical repair in the acute (within 10 d) and nonacute stage (>6 wk). Prospective study. Tertiary referral center Patients diagnosed with SCDS (n = 32) and healthy control subjects (n = 51). Surgical canal plugging on a subset of patients. Static visual acuity (SVA), active horizontal DVA, and canal plane htDVA. Visual acuity (SVA, active DVA, and htDVA) declines with age. In SCDS, SVA and active DVA are not significantly affected in individuals after surgical canal plugging; however, htDVA in the plane of the affected canal is significantly worse after canal plugging. Age-based normative data are necessary for DVA testing. In SCDS, htDVA in the plane of the affected canal is normal before surgery but permanently reduced afterward.

  8. Antibacterial activity of 2% chlorhexidine gluconate and 5.25% sodium hypochlorite in infected root canal: in vivo study.

    Science.gov (United States)

    Ercan, Ertuğrul; Ozekinci, Tuncer; Atakul, Fatma; Gül, Kadri

    2004-02-01

    In this study, the antibacterial activity of the different antibacterial solutions using as root canal irrigant was compared in the teeth with pulpal necrosis and with periapical pathosis. Thirty root canals of incisors and premolars of 20 patients were used. Before and after the root canal preparation, two canal samples were obtained by a harvesting method using a sterile paper point in the first appointment. During the biomechanical preparation, both irrigant solutions were used for each tooth which were randomly divided into two groups. Last samples were also obtained before the root filling procedure. Samples obtained from the root canals were subjected to microbiologic processing, including anaerobic incubation on trypticase soy agar for 5 to 7 days. After counting of CFU on the plates, we concluded that both chlorhexidine gluconate and sodium hypochlorite were significantly effective to reduce the microorganisms in the teeth with necrotic pulp, periapical pathologies, or both, and could be used successfully as an irrigant solution.

  9. Specific immunoglobulin measurements related to exposure and resistance to Schistosoma mansoni infection in Sudanese canal cleaners

    DEFF Research Database (Denmark)

    Satti, M.Z.; Lind, Peter; Vennervald, B.J.

    1996-01-01

    was used to detect specific IgE and IgG subclasses in response to whole worm antigen (WWH) and soluble egg antigen (SEA) before and 3 months after praziquantel treatment in the groups of canal cleaners and before and 1 year after treatment in normally exposed adults. When intensity of infection...

  10. Supporting inland waterway transport on German waterways by operational forecasting services - water-levels, discharges, river ice

    Science.gov (United States)

    Meißner, Dennis; Klein, Bastian; Ionita, Monica; Hemri, Stephan; Rademacher, Silke

    2017-04-01

    Inland waterway transport (IWT) is an important commercial sector significantly vulnerable to hydrological impacts. River ice and floods limit the availability of the waterway network and may cause considerable damages to waterway infrastructure. Low flows significantly affect IWT's operation efficiency usually several months a year due to the close correlation of (low) water levels / water depths and (high) transport costs. Therefore "navigation-related" hydrological forecasts focussing on the specific requirements of water-bound transport (relevant forecast locations, target parameters, skill characteristics etc.) play a major role in order to mitigate IWT's vulnerability to hydro-meteorological impacts. In light of continuing transport growth within the European Union, hydrological forecasts for the waterways are essential to stimulate the use of the free capacity IWT still offers more consequently. An overview of the current operational and pre-operational forecasting systems for the German waterways predicting water levels, discharges and river ice thickness on various time-scales will be presented. While short-term (deterministic) forecasts have a long tradition in navigation-related forecasting, (probabilistic) forecasting services offering extended lead-times are not yet well-established and are still subject to current research and development activities (e.g. within the EU-projects EUPORIAS and IMPREX). The focus is on improving technical aspects as well as on exploring adequate ways of disseminating and communicating probabilistic forecast information. For the German stretch of the River Rhine, one of the most frequented inland waterways worldwide, the existing deterministic forecast scheme has been extended by ensemble forecasts combined with statistical post-processing modules applying EMOS (Ensemble Model Output Statistics) and ECC (Ensemble Copula Coupling) in order to generate water level predictions up to 10 days and to estimate its predictive

  11. RETRATAMENTO ENDODÔNTICO: ESTUDO COMPARATIVO ENTRE TÉCNICA MANUAL, ULTRA-SOM E CANAL FINDER ENDODONTIC RETREATMENT: COMPARATIVE STUDY BETWEEN MANUAL TECHNIQUE, ULTRASONIC SCALER, AND CANAL FINDER

    Directory of Open Access Journals (Sweden)

    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.

  12. Evaluate root and canal morphology of primary mandibular second molars in Chinese individuals by using cone-beam computed tomography.

    Science.gov (United States)

    Yang, Ran; Yang, Chan; Liu, Yuan; Hu, Yong; Zou, Jing

    2013-07-01

    More detailed knowledge of root and canal morphology is important in order to improve the success in the endodontics of primary teeth. The purpose of this study was to evaluate the root and canal morphology of primary mandibular second molars (PMSMs) in a Chinese population using cone-beam computed tomography (CBCT). CBCT images, which had been obtained previously in the West China Hospital of Stomatology at Sichuan University, Chengdu, China between May 2009 and December 2011, were screened retrospectively. Finally, 283 individuals-207 male and 76 female with a mean age of 7.2 years (range 3-10 years)-and 487 PMSMs with clear images of root and canal morphology were enrolled. The number of roots and morphology of canals were recorded. The patient's gender, and the symmetry and frequency of three roots in PMSMs were analyzed. The majority of PMSMs had two (72.28%) or three roots (27.52%). The symmetrical incidence of three-root PMSMs in this Chinese population was 50.65%. There is no difference between genders in the prevalence of an extra root and the incidence of symmetry (p > 0.05). Of the individuals enrolled, 25.26% of PMSMs had three canals and 73.31% had four canals. The root canal systems of the PMSMs in the present study were categorized into seven variants. This study indicated that three-rooted PMSMs occur frequently in the Chinese population. There was no difference between the two genders on incidence and symmetry. The majority of PMSMs have three to four canals and the diversity of the root canal variants should be considered when performing clinical procedures. CBCT is a good option for studying the root and canal morphology of primary teeth. Copyright © 2012. Published by Elsevier B.V.

  13. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength.

    Science.gov (United States)

    Rippe, Marília Pivetta; Santini, Manuela Favarin; Bier, Carlos Alexandre Souza; Baldissara, Paolo; Valandro, Luiz Felipe

    2014-06-01

    To evaluate the impact of the type of root canal preparation, intraradicular post and mechanical cycling on the fracture strength of roots. eighty human single rooted teeth were divided into 8 groups according to the instruments used for root canal preparation (manual or rotary instruments), the type of intraradicular post (fiber posts- FRC and cast post and core- CPC) and the use of mechanical cycling (MC) as follows: Manual and FRC; Manual, FRC and MC; Manual and CPC; Manual, CPC and MC; Rotary and FRC; Rotary, FRC and MC; Rotary and CPC; Rotary, CPC and MC. The filling was performed by lateral compactation. All root canals were prepared for a post with a 10 mm length, using the custom #2 bur of the glass fiber post system. For mechanical cycling, the protocol was applied as follows: an angle of incidence of 45°, 37°C, 88 N, 4 Hz, 2 million pulses. All groups were submitted to fracture strength test in a 45° device with 1 mm/ min cross-head speed until failure occurred. The 3-way ANOVA showed that the root canal preparation strategy (ppost type (ppost and mechanical cycling, so it does not seem to be an important factor in this scenario.

  14. Mental foramen and lingual vascular canals of mandible on MDCT images: anatomical study and review of the literature.

    Science.gov (United States)

    Direk, Filiz; Uysal, Ismihan Ilknur; Kivrak, Ali Sami; Fazliogullari, Zeliha; Unver Dogan, Nadire; Karabulut, Ahmet Kagan

    2017-04-13

    The mental foramen and lingual vascular canals are related to vessels and nerves in the mandibular body. The aim of the present study was to determine the number and location of these structures and to make measurements of them. The archived Multidetector Computed Tomography images of 100 adult (15- to 70-year-old) patients were evaluated retrospectively. The diameters of the mental foramens and their distances from the front, back, upper and lower reference points were measured. The distribution of mental foramens with respect to the teeth was also researched. The presence of lingual vascular canals, and the number of median and lateral canals was determined, and the length of the median lingual vascular canals measured. All measurement parameters were analyzed by gender, side and age group. Eleven patients demonstrated a total of 15 accessory mental foramen. Median lingual vascular canals were observed in 100% of cases, with lateral lingual vascular canals determined in 32%. Significant differences were observed in the results of different gender groups (P foramen was determined mostly in males, and unilaterally on the right side; also, the distances of mental foramen, except the distance from the back border of the mandible (P foramen, as well as the presence, position and size of lingual vascular canals can be clearly investigated by multidetector computed tomography. A preoperative knowledge of the positions of neurovascular and bone structures is very important for preventing complications that may occur during or after operations.

  15. "The Panama Canal Episode: An Encounter with a Question and Answers." Occasional Paper 3.

    Science.gov (United States)

    Seifman, Eli

    This is an account of the experience of a college instructor and a group of prospective social studies teachers as they answer a simple question concerned with direction of travel through the Panama Canal and explore the reactions of students. The situation originates in a class discussion focusing on ways of asking and responding to classroom…

  16. Micro-CT analyses of apical enlargement and molar root canal complexity

    DEFF Research Database (Denmark)

    Markvart, Merete; Darvann, Tron Andre; Larsen, Per

    2012-01-01

    AIM: To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical enlargement in molar teeth and to quantify and visualize spatial details of instrumentation efficacy in root canals of different complexity. METHODOLOGY: Maxillary and mandibular molar teeth wer...

  17. Effect of Lengthy Root Canal Therapy Sessions on Temporomandibular Joint and Masticatory Muscles

    Directory of Open Access Journals (Sweden)

    Safoora Sahebi

    2010-09-01

    Full Text Available Background and aims. Trauma is one of the major factors associated with temporomandibular joint disorders (TMD. These disorders result from macro-trauma or micro-trauma. Macro-trauma might be iatrogenic; for example, from intubation procedures, third molar extraction procedures, and lengthy dental appointments. The aim of this study was to evaluate the effect of lengthy root canal therapy (more than 2 hours on TMJ and its supporting structures. Materials and methods. Eighty patients whose root canal therapy session lasted more than 2 hours were examined for the status of TMJ and masticatory muscles. After one week the second part of the examination was carried out for TMJ problems and pain and tenderness levels of masticatory muscles. Data was analyzed using Wilcoxon statistical test. Results. Women showed more pain compared to men. There was a significant increase in pain in the external acoustic meatus examination one week after root canal therapy. Patients who were treated for their posterior teeth suffered more pain than those who were treated for the anteriors and premolars. Other aspects of the examination were not affected significantly by lengthy root canal therapy. Conclusion. Lengthy dental treatments can harm TMJ and masticatory muscles and wide opening of the mouth during such appointments can worsen the situation. Therefore, it is wise to break the appointment into shorter intervals and let the patients rest during treatment to close their mouth to prevent iatrogenic damage to TMJ.

  18. [CT morphology of mandibular bone and mandibular nerve canal in hemimandibular elongation].

    Science.gov (United States)

    Zhang, Gui-Mei; Wang, Tao; Mao, Xiaobin; Yang, Dongkun

    2012-04-01

    To study morphology feature of mandibular anatomical characteristics and mandibular nerve canal of hemimandibular elongation (HE) using CT, and provide reference for the clinical treatment. 19 patients with HE were scanned using multidetector CT. Mimics 10.0 software was used for three-dimensional reconstruction, and CT images were reconstructed on different sections. The position of mandibular nerve canal, mandibular foramen and thickness of mandibular cortical bone were measured, and compared with control group (without mandibular lesion). Compared with the control group, the distance between mandibular nerve canal and mandibular surface were statistically different at the section of long axis of mandibular first molar centre (LAMFM)-lingual, long axis of mandibular second molar centre (LAMSM)-buccal, LAMSM-superior, retromolar area centre to the mandibular angle (RAC-MA)-buccal, RAC-MA-superior, RAC-MA-inferior and horizontal level of mandibular foramen under 5 mm (HLMFU5)-lingual, HLMFU5-anterior, HLMFU5-posterior (Pmandibular cortical bone were statistically different at the LAMFM-buccal, LAMFM-inferior (Pmandibular foramen (LPMF)-superior border of mandibular ramus (SBMR) and LPMF-inferior border of mandibular ramus (IBMR) were statistically different (Pmandibular cortical bone gradually decreases in all directions from the mandibular first molar to the mandibular ramus. Compared with the control group, mandibular nerve canal located buccally and superiorly at mandibular second molar and retromolar area, mandibular foramen located more anterior and lower inside mandibular ramus.

  19. Distributed control at Love canal

    Energy Technology Data Exchange (ETDEWEB)

    McPherson, G.; Rider, G.J.; Sadowski, B.; Moore, M.

    1994-09-01

    Love Canal is known worldwide as the site of one of the worst non-nuclear environmental disasters in modern history. For 12 years, a Niagara Falls, New York chemical company used the canal bed as a chemical dump. This article discusses the computerized control of equipment used to remove the toxic materials from the ground under Love Canal, and how the minimization of maintenance is reducing maintenance costs and increasing operator safety.

  20. Impact of lining material on chemical and microbial irrigation water quality of Nubaria canal, Egypt

    Directory of Open Access Journals (Sweden)

    Ahmed Mohamed Azzam

    2016-02-01

    Full Text Available Objective: To assess the effect of lining material (cement of Nubaria canal (Beheira Governorate, Egypt on its water quality. Methods: Trace metal ions (Fe, Zn, Cu, Pb, and Cd and bacterial indictors for water samples collected from two types of stations (lined and unlined during successive four seasons were analyzed. The effect of lining on bacterial indicators; total viable bacterial count at 22 and 37 °C, total coliform, fecal coliform and fecal streptococci and presence of some bacterial species were studied. Results: Bacterial indicators and trace metals showed seasonal variations, where the highest values were recorded during summer. A significant reduction for Cu (P < 0.05, Zn (P < 0.01 and Cd (P < 0.001 was recorded in lined stations compared to those of unlined ones. Bacterial indicators recorded the lowest counts in lined stations during all seasons, while there was a significant reduction (P < 0.05 between total coliform values (1.70 ± 0.50 in lined stations and unlined ones (3.57 ± 1.01 during summer. Escherichia coli bacteria were predominant in water samples of Nubaria canal, where it recorded 34.4% of bacterial isolates. Conclusions: Lined material plays a role for reducing the bacterial growth and metals concentration, therefore the lining of canal helps in preventing the discharge of sewage pollution into canal.

  1. Analysis of sedimentation of canals

    Directory of Open Access Journals (Sweden)

    Agunwamba, J.C.,

    2013-03-01

    Full Text Available The dredged canals in the Niger Delta coastal flood plain are being threatened by siltation. This study is limited to those canals in Rivers State of Nigeria, which are under the influence of tidal waves. A total of eight canals were considered with four each from Ekulama and Cawthorne Channel. Different approaches were used to carry out this study, which includes field reconnaissance survey, hydrographic survey, soil sample analysis and collection of all available data and information. The typical bed materials size (D50 is approximately 0.01mm; which gives a settling velocity of 0.09mm/sec using stroke’s law. Hydrographic survey of the canals from 1992 to 1996 revealed an average siltation rate of 2.35m/yr. A regression equation was also derived which relates the cost of dredging to canal area, rate of siltation and average aggregation. A plot of canal centre profile; entrance, middle and end cross sections showing sediment distribution along the canal profile, shows that majority of the particles that form the sediment enter the canal from the rivers. The sedimentation is caused by the reduction in water current, which has average value of 0.0145m/sec. The bathyorographical check on the canals revealed that the sum of the two exterior angles of the canal with the river at the point of connection has to lie within 1800 + 50 for an effective flow that will minimize settlement of particles. In addition, the canals should be constructed to start and terminate on a moving water body, to avoid dead ends. A regression equation was determined which relates the cost of dredging to canal area, rate of siltation and average aggradations.

  2. A clinical and radiographic study of four different root canal fillings in primary molars

    Directory of Open Access Journals (Sweden)

    Alaa O Al-Ostwani

    2016-01-01

    Full Text Available Background: Successful treatment of infected primary teeth aims to preserve the child′s health. However, the complex morphology of primary root canals and the desire for shorter therapy sessions put the necessity to search for the ideal root canal paste. Aims: To evaluate pulpectomy of nonvital primary molars using four different root canal filling pastes zinc oxide and propolis (ZOP as a new paste, endoflas-chlorophenol-free as a new paste free of chlorophenol, metapex paste, and zinc oxide and eugenol (ZOE paste as a control paste. Materials and Methods: Pulpectomy of 64 nonvital primary molars were accomplished in 39 children aged 3-9 years. Teeth were randomly divided into four equal groups of 16 molars according to the type of root canal filling. Pulpectomy was performed in one stage using 5.25% sodium hypochlorite irrigation and stainless-steel crown for final restoration. Clinical and radiographic results were evaluated double-blindly for two periods of 6, 12 months. Data were analyzed using Chi-square/Fisher′s exact test, and P-value was set as 0.05. Results: The four pastes achieved convergent clinical and radiographic success within the two observation periods (P > 0.05. ZOE paste was the slowest in its resorption. Conclusions: ZOP is a promising paste with its natural antibacterial component (propolis. ZOE paste had convergent efficacy to the other pastes.

  3. The Effects of Silicone and Acrylic Ear Mold Materials on Outer Ear Canal Resonance Characteristics.

    Science.gov (United States)

    Alnıaçık Erdoğan, Asuman; Arslan, Şeyda Nur

    2016-08-01

    The aim of this study is to investigate the effects of earmolds made of silicone and acrylic on outer ear canal resonance characteristics in terms of resonance frequency and amplitude measured in a hearing aid fitting. Outer ear canal resonance frequencies and amplitudes in open ears and those measured with silicone and acrylic ear molds were obtained from 30 participants between the ages of 20 and 25 years (average age, 22.0 years; 18 females and 12 males) with a real ear gain measurement. To observe the changes depending on probe tube placement, test-retest variation was investigated in 10 participants before the study. There was no statistically significant difference between open ear canal resonance frequencies and those measured with silicone and acrylic earmolds (p>0.05). the silicone earmold resonance amplitude values were statistically significantly lower than the open ear canal resonance amplitudes when compared to those of the acrylic earmolds (p<0.05). Depending on the changes occurring in outer ear resonance features as a result of earmold materials used in hearing aid fittings, the application of earmolds should be done by experienced specialists.

  4. Audiologic, cVEMP, and Radiologic Progression in Superior Canal Dehiscence Syndrome

    NARCIS (Netherlands)

    Lookabaugh, Sarah; Niesten, Marlien E F; Owoc, Maryanna; Kozin, Elliott D.; Grolman, Wilko; Lee, Daniel J.

    2016-01-01

    OBJECTIVE:: To assess the change in hearing, vestibular function, and size of superior canal dehiscence (SCD) in patients with SCD syndrome over time. PATIENTS:: Adult patients with SCD in one or both ears with documented sign and symptom progression, as shown by the medical record, audiometry,

  5. Child Development in the Context of Adversity: Experiential Canalization of Brain and Behavior

    Science.gov (United States)

    Blair, Clancy; Raver, C. Cybele

    2012-01-01

    The authors examine the effects of poverty-related adversity on child development, drawing upon psychobiological principles of experiential canalization and the biological embedding of experience. They integrate findings from research on stress physiology, neurocognitive function, and self-regulation to consider adaptive processes in response to…

  6. Aspects of the anatomy and histology of the alimentary canal of the ...

    African Journals Online (AJOL)

    Aspects of the anatomy and histology of the alimentary canal of Thryonomys swinderianus were studied to gain a better understanding of this animal's ability to digest large quantities of fibre. Morphometric measurements of the gut regions were taken with the aid of light, transmission and scanning electron microscopy.

  7. CT study of the performance of reciprocating and oscillatory motions in flattened root canal areas

    Energy Technology Data Exchange (ETDEWEB)

    Moura-Netto, Cacio, E-mail: caciomn@usp.br [Universidade Cruzeiro do Sul (UNICSUL), Sao Paulo, SP (Brazil). Fac. de Odontologia; Palo, Renato Miotto [Universidade Estadual Paulista Julio de Mesquita Filho (ICT/UNESP), Sao Jose dos Campos, SP (Brazil). Instituto de Ciencia e Tecnologia; Pinto, Larissa Fernanda; Daltoe, Gisele; Mello-Moura, Anna Carolina Volpi [Universidade Ibirapuera (UNIB), Sao Paulo, SP (Brazil). Fac. de Odontologia

    2015-03-01

    Abstract: Root canal preparation is an important step in endodontic treatment. The anatomical complexity of the middle third of the root compromises the effective cleaning of this area. Thus, advances have been made in instrumentation techniques and instruments for this purpose. The aim of this study was to evaluate the effects of three different instrumentation systems on the enlargement of the middle thirds of root canals in mandibular incisors. The preparation methods used were the reciprocating systems Reciproc (Group I) and WaveOne (Group II) and the oscillatory system Tilos (Group III). Comparisons were made by three-dimensional image reconstruction with cone-beam computed tomography before and after instrumentation. Changes in area, perimeter, centering ability, and pattern of preparation were analyzed. The results were subjected to ANOVA complemented by the Tukey’s test. Changes in area, perimeter, and tendency of transportation showed similar results among groups. The transportation index of the Tilos system was significantly lower than that of the other groups. Qualitative analysis of the preparation pattern showed that the Tilos system had a more uniform preparation, although Reciproc and WaveOne preparations appeared more rounded, incompatible with the original canal anatomy. There was similarity in the systems’ performance on flattened areas, although the Tilos system presented a better pattern of root canal preparation and a lower index of transportation. (author)

  8. A clinical and radiographic study of four different root canal fillings in primary molars.

    Science.gov (United States)

    Al-Ostwani, Alaa O; Al-Monaqel, Bashier M; Al-Tinawi, Mohamed K

    2016-01-01

    Successful treatment of infected primary teeth aims to preserve the child's health. However, the complex morphology of primary root canals and the desire for shorter therapy sessions put the necessity to search for the ideal root canal paste. To evaluate pulpectomy of nonvital primary molars using four different root canal filling pastes zinc oxide and propolis (ZOP) as a new paste, endoflas-chlorophenol-free as a new paste free of chlorophenol, metapex paste, and zinc oxide and eugenol (ZOE) paste as a control paste. Pulpectomy of 64 nonvital primary molars were accomplished in 39 children aged 3-9 years. Teeth were randomly divided into four equal groups of 16 molars according to the type of root canal filling. Pulpectomy was performed in one stage using 5.25% sodium hypochlorite irrigation and stainless-steel crown for final restoration. Clinical and radiographic results were evaluated double-blindly for two periods of 6, 12 months. Data were analyzed using Chi-square/Fisher's exact test, and P-value was set as 0.05. The four pastes achieved convergent clinical and radiographic success within the two observation periods (P > 0.05). ZOE paste was the slowest in its resorption. ZOP is a promising paste with its natural antibacterial component (propolis). ZOE paste had convergent efficacy to the other pastes.

  9. Development of the myocardium of the atrioventricular canal and the vestibular spine in the human heart

    NARCIS (Netherlands)

    Kim, J. S.; Virágh, S.; Moorman, A. F.; Anderson, R. H.; Lamers, W. H.

    2001-01-01

    To establish the morphogenetic mechanisms underlying formation and separation of the atrioventricular connections, we studied the remodeling of the myocardium of the atrioventricular canal and the extracardiac mesenchymal tissue of the vestibular spine in human embryonic hearts from 4.5 to 10 weeks

  10. Canal Transportation, Unprepared Areas, and Dentin Removal after Preparation with BT-RaCe and ProTaper Next Systems.

    Science.gov (United States)

    Brasil, Sabrina C; Marceliano-Alves, Marília F; Marques, Márcia L; Grillo, João P; Lacerda, Mariane F L S; Alves, Flávio R F; Siqueira, José F; Provenzano, José C

    2017-10-01

    This study compared the shaping ability of ProTaper Next (Dentsply Sirona, Tulsa, OK) and BT-RaCe (FKG Dentaire, La Chaux-de-Fonds, Switzerland) instrument systems in the mesial canals of mandibular molars using micro-computed tomographic (micro-CT) imaging. A total of 17 type IV mesial roots of extracted first mandibular molars were scanned using micro-CT imaging before and after root canal preparation with the 2 instrument systems. Both systems were used in the same root but alternating the mesial canals from root to root. The following parameters were analyzed: root canal volume, surface area, unprepared surface areas, transportation, canal/root width ratio, and preparation time. There were no statistically significant differences between the 2 systems for all evaluated parameters (P > .05). The unprepared surface areas for the full canal length and the apical 5-mm segment were 33% and 14% for BT-RaCe and 31% and 14% for ProTaper Next, respectively. After preparation, all root canals had a diameter that was not larger than 35% of the root diameter at the coronal and middle segments. The 2 systems showed no differences in any of the evaluated shaping parameters. None of the tested systems put the roots at risk of fracture because of excessive dentin removal. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. Antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in infected human root canals.

    Science.gov (United States)

    Estrela, C; Estrela, C R A; Decurcio, D A; Hollanda, A C B; Silva, J A

    2007-02-01

    To determine the antimicrobial efficacy of ozonated water, gaseous ozone, sodium hypochlorite and chlorhexidine in human root canals infected by Enterococcus faecalis. Thirty human maxillary anterior teeth were prepared and inoculated with E. faecalis for 60 days. Eppendorf tubes were connected to the coronal portion of the teeth. Urethane hoses were attached to the tubes and to the entrance of a peristaltic pump. The exit of the apparatus corresponded to the apical portion of the root canals. The test irrigating solutions were ozonated water, gaseous ozone, 2.5% sodium hypochlorite (NaOCl), 2% chlorhexidine that circulated at a constant flow of 50 mL min(-1) for 20 min. Samples from the root canals were collected and immersed in 7 mL Letheen Broth (LB), followed by incubation at 37 degrees C for 48 h. Bacterial growth was analysed by turbidity of the culture medium and subculture on a specific nutrient broth. A 0.1 mL inoculum obtained from LB was transferred to 7 mL of brain heart infusion and incubated at 37 degrees C for 48 h. Bacterial growth was checked by turbidity of the culture medium carried out in triplicate. No solution used as an irrigant over a 20-min contact time demonstrated an antimicrobial effect against E. faecalis. The irrigation of infected human root canals with ozonated water, 2.5% NaOCl, 2% chlorhexidine and the application of gaseous ozone for 20 min was not sufficient to inactivate E. faecalis.

  12. Rare Case of Anal Canal Signet Ring Cell Carcinoma Associated with Perianal and Vulvar Pagetoid Spread

    Directory of Open Access Journals (Sweden)

    Na Rae Kim

    2016-05-01

    Full Text Available A 61-year-old woman was referred to surgery for incidentally found colonic polyps during a health examination. Physical examination revealed widespread eczematous skin lesion without pruritus in the perianal and vulvar area. Abdominopelvic computed tomography showed an approximately 4-cm-sized, soft tissue lesion in the right perianal area. Inguinal lymph node dissection and Mils’ operation extended to perianal and perivulvar skin was performed. Histologically, the anal canal lesion was composed of mucin-containing signet ring cells, which were similar to those found in Pagetoid skin lesions. It was diagnosed as an anal canal signet ring cell carcinoma (SRCC with perianal and vulvar Pagetoid spread and bilateral inguinal lymph node metastasis. Anal canal SRCC is rare, and the current case is the third reported case in the English literature. Seven additional cases were retrieved from the world literature. Here, we describe this rare case of anal canal SRCC with perianal Pagetoid spread and provide a literature review.

  13. Numerical modeling of the 1964 Alaska tsunami in western Passage Canal and Whittier, Alaska

    Directory of Open Access Journals (Sweden)

    D. J. Nicolsky

    2010-12-01

    Full Text Available A numerical model of the wave dynamics in Passage Canal, Alaska during the Mw 9.2 megathrust earthquake is presented. During the earthquake, several types of waves were identified at the city of Whittier, located at the head of Passage Canal. The first wave is thought to have been a seiche, while the other two waves were probably triggered by submarine landslides. We model the seiche wave, landslide-generated tsunami, and tectonic tsunami in Passage Canal and compute inundation by each type of wave during the 1964 event. Modeled results are compared with eyewitness reports and an observed inundation line. Results of the numerical experiments let us identify where the submarine landslides might have occurred during the 1964 event. We identify regions at the head and along the northern shore of Passage Canal, where landslides triggered a wave that caused most of the damage in Whittier. An explanation of the fact that the 1964 tectonic tsunami in Whittier was unnoticed is presented as well. The simulated inundation by the seiche, landslide-generated tsunami, and tectonic tsunami can help to mitigate tsunami hazards and prepare Whittier for a potential tsunami.

  14. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    Science.gov (United States)

    Georgi, Justin A; Sipla, Justin S; Forster, Catherine A

    2013-01-01

    Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function.

  15. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    Directory of Open Access Journals (Sweden)

    Justin A Georgi

    Full Text Available Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function.

  16. Influence of the Houma Navigation Canal on Salinity Patterns and Landscape Configuration in Coastal Louisiana

    Science.gov (United States)

    Steyer, Gregory D.; Sasser, Charles; Evers, Elaine; Swenson, Erick; Suir, Glenn; Sapkota, Sijan

    2008-01-01

    Coastal Louisiana is a dynamic and ever changing landscape. From 1956 to 2004, over 297,000 ha of Louisiana's coastal wetlands were lost because of the effects of natural and human-induced activities. Studies show that, in 2005, Hurricanes Katrina and Rita transformed over 56,200 ha of wetlands to open water in various parts of coastal Louisiana. Besides the catastrophic hurricanes, factors such as subsidence, sea-level rise, freshwater and sediment deprivation, saltwater intrusion, the dredging of oil and gas canals, navigation canals, shoreline erosion, and herbivory are all contributors to wetland loss in Louisiana. Various scientific literatures have well described the direct impacts associated with an immediate physical conversion of habitat in coastal Louisiana; however, the indirect impacts that are subtle and operate over longer time horizons (such as salinity intrusion) have been difficult to discern. In this report, long-term influences on salinity patterns and landscape configuration are evaluated for pre- and postconstruction periods of the Houma Navigation Canal (HNC), which is located in the coastal region of southeastern Louisiana. Analysis of daily and hourly salinity data from long-term data collection stations within the areas surrounding the HNC indicated that there were no obvious patterns in increasing salinity levels following the completion of the canal, except for the immediate increase in salinity spikes that occurred toward the completion of its construction in 1961. Increases in salinity spikes were also observed during a severe drought in 1999-2000. Data from Bayou Grand Caillou at Dulac, however, show a longer term trend of increasing salinity levels, which is similar to the pattern observed at the Houma Water Treatment Plant. A potential explanation for these patterns is based on the dredging history of the HNC, where dates of maintenance dredging correspond fairly closely to the salinity peaks in Bayou Grand Caillou and the canal. It

  17. Comparison of Endoflas and Zinc oxide Eugenol as root canal filling materials in primary dentition

    Directory of Open Access Journals (Sweden)

    Nivedita Rewal

    2014-01-01

    Full Text Available Background: Zinc oxide eugenol has long been the material of choice of pediatric dentists worldwide, although it fails to meet the ideal requirements of root canal filling material for primary teeth. Endoflas, a mixture of zinc oxide eugenol, calcium hydroxide, and iodoform, can be considered to be an effective root canal filling material in primary teeth as compared with zinc oxide eugenol. This study was carried out to compare zinc oxide eugenol with endoflas for pulpectomy in primary dentition. Aim: The objective of the study was to compare clinically and radiographically success rates of zinc oxide eugenol with endoflas for the root canal filling of primary teeth at 3, 6, and 9 months. Design: Fifty primary molars were included in the study with 26 teeth in Group I (Endoflas and 24 in Group II (zinc oxide eugenol. A single visit pulpectomy was carried out. Results: The overall success rate of zinc oxide eugenol was 83% whereas 100% success was found in the case of endoflas. The obtained results were compiled and subjected to statistical analysis using the chi-square test. The difference in the success rate between the two was statistically significant (P < 0.05. Conclusion: Endoflas has shown to have better results than zinc oxide eugenol. It should therefore be the material of choice for root canal treatment in deciduous dentition.

  18. Neurovascular Content of the Mandibular Canal and Its Clinical Relevance: A Literature Review of the Related Anatomical and Radiological Studies

    Directory of Open Access Journals (Sweden)

    Eliades Apostolos N.

    2014-11-01

    Full Text Available In literature, anatomical variations of the inferior alveolar nerve branches (infratemporal, extraosseous and intraosseous are reported and their importance in clinical practice is discussed too. The spatial vessels’ position in relationship with the nerve in the mandibular canal was explored, which is of clinical significance in impacted third molar and implant surgery. It is believed that the neurovascular content of the main mandibular canal follows any variations of the mandibular canal i.e. bifid mandibular, retromolar and accessory mental canals. Retrospective studies and case reports reported the presence of multiple foramina on the medial surface of the ramus, near the main mandibular foramen. In some cases, one supplementary mandibular foramen was found to be connected with the lower third molar, which is called “temporal crest canal”. Others found an accessory mandibular foramen that led into a second mandibular canal which joined the main mandibular canal (double anteriorly. The bony canals contained a terminal branch of the anterior trunk of the mandibular nerve or a branch of inferior alveolar nerve before it entered the mandibular foramen.

  19. Cleaning lateral morphological features of the root canal: the role of streaming and cavitation.

    Science.gov (United States)

    Robinson, J P; Macedo, R G; Verhaagen, B; Versluis, M; Cooper, P R; van der Sluis, L W M; Walmsley, A D

    2018-01-01

    To investigate the effects of ultrasonic activation file type, lateral canal location and irrigant on the removal of a biofilm-mimicking hydrogel from a fabricated lateral canal. Additionally, the amount of cavitation and streaming was quantified for these parameters. An intracanal sonochemical dosimetry method was used to quantify the cavitation generated by an IrriSafe 25 mm length, size 25 file inside a root canal model filled with filtered degassed/saturated water or three different concentrations of NaOCl. Removal of a hydrogel, demonstrated previously to be an appropriate biofilm mimic, was recorded to measure the lateral canal cleaning rate from two different instruments (IrriSafe 25 mm length, size 25 and K 21 mm length, size 15) activated with a P5 Suprasson (Satelec) at power P8.5 in degassed/saturated water or NaOCl. Removal rates were compared for significant differences using nonparametric Kruskal-Wallis and/or Mann-Whitney U-tests. Streaming was measured using high-speed particle imaging velocimetry at 250 kfps, analysing both the oscillatory and steady flow inside the lateral canals. There was no significant difference in amount of cavitation between tap water and oversaturated water (P = 0.538), although more cavitation was observed than in degassed water. The highest cavitation signal was generated with NaOCl solutions (1.0%, 4.5%, 9.0%) (P cavitation and acoustic streaming have provided insight into their contribution to cleaning. Significant differences in cleaning, cavitation and streaming were found depending on the file type and size, lateral canal location and irrigant used. In general, the IrriSafe file outperformed the K-file, and NaOCl performed better than the other irrigants tested. The cavitation and streaming measurements revealed that both contributed to hydrogel removal and both play a significant role in root canal cleaning. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. 75 FR 17158 - Chesapeake and Ohio Canal National Historical Park Advisory Commission; Notice of Public Meeting

    Science.gov (United States)

    2010-04-05

    ... Advisory Commission (the Commission) will be held at 9 a.m., on Friday, May 14, 2010, at the House of Sweden, 2900 K Street, NW., Washington, DC 20007. DATES: Friday, May 14, 2010. ADDRESSES: House of Sweden... and Ohio Canal National Historical Park Headquarters, 1850 Dual Highway, Suite 100, Hagerstown...

  1. Comparison of different retreatment techniques and root canal sealers: a scanning electron microscopic study

    Directory of Open Access Journals (Sweden)

    Neslihan Simsek

    2014-05-01

    Full Text Available The aim of this study was to evaluate the effectiveness of two retreatment techniques, in terms of the operating time and scanning electron microscopy (SEM results, in removing three different root canal sealers from root canals that were previously filled with gutta-percha. Sixty extracted single-rooted human premolars were divided into three groups and filled with iRoot SP, MM Seal, and AH Plus sealers, along with gutta-percha, through a lateral compaction technique. Root canal fillings of the samples were removed by ESI ultrasonic tips or R-Endo files. The time to reach the working length was recorded. Longitudinally sectioned samples were examined under SEM magnification. Each picture was evaluated in terms of the residual debris. Data were statistically analyzed with the Kruskall-Wallis test. No statistically significant differences were found in terms of operating time (p>0.05. Significant differences in the number of debris-free dentinal tubules were found among the root canal thirds, but this finding was not influenced by the experimental group (p < 0.05. Resin sealer tags were observed inside the dentinal tubules in the MM Seal group. Under the conditions of this study, it may be established that there was no difference among the sealers and retreatment techniques.

  2. Predictive control of irrigation canals – robust design and real-time implementation

    NARCIS (Netherlands)

    Aguilar, José V.; Langarita, Pedro; Rodellar, José; Linares, Lorenzo; Horváth, K.

    2016-01-01

    Predictive control is one of the most commonly used control methods in a variety of application areas, including hydraulic processes such as water distribution canals for irrigation. This article presents the design and application of predictive control for the water discharge entering into an

  3. Opinion Polls and the Panama Canal Treaties of 1977: A Critical Analysis.

    Science.gov (United States)

    Smith, Ted J., III; Hogan, J. Michael

    Noting that 1977 public opinion polls concerning the new Panama Canal treaties were interpreted as showing increased support for the treaties, this paper contends that this interpretation was erroneous and that the major outcome of the extensive polling was misleading data. The paper is divided into three major analytical sections. The first…

  4. Seepage study of the South Bend, Richfield, and Vermillion Canals, Sevier County, Utah

    Science.gov (United States)

    Herbert, L.R.; Smith, G.J.

    1989-01-01

    A seepage investigation was made in 1987 on selected reaches of the South Bend, Richfield, and Vermillion Canals in Sevier County, Utah, to determine gains or losses in discharge.  Fluctuations in discharge were adjusted using information from stage recorders operated at selected locations during each set of discharge measurements. The investigation showed a net gain of 0.2 cubic foot per second in the South Bend canal: the upper reach gained 1.5 cubic feet per second, the two middle reaches together lost 2.5 cubic feet per second, and the lower reach gained 1.2 cubic feet per second.  The Richfield Canal showed a net loss of 2.4 cubic feet per second: the two upper reaches together lost 4.4 cubic feet per second and the two lower reaches together gained 2.0 cubic feet per second.  The Vermillion canal showed a net loss of 0.2 cubic foot per second: the upper reach gained 2.3 cubic feet per second and the lower reach lost 2.5 cubic feet per second.

  5. Micro‐CT analyses of apical enlargement and molar root canal complexity

    DEFF Research Database (Denmark)

    Markvart, M.; Darvann, Tron Andre; Larsen, P.

    2012-01-01

    Markvart M, Darvann TA, Larsen P, Dalstra M, Kreiborg S, Bjørndal L. Micro‐CT analyses of apical enlargement and molar root canal complexity. International Endodontic Journal, 45, 273–281, 2012. Aim To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical...

  6. On the waterfront : water distribution, technology and agrarian change in a South Indian canal irrigation system

    NARCIS (Netherlands)

    Mollinga, P.P.

    1998-01-01

    This book discusses water distribution in the Tungabhadra Left Bank Canal irrigation system in Raichur district, Karnataka, India. The system is located in interior South India, where rainfall is limited (approximately 600 mm annually) and extremely variable. The region suffered from failed

  7. Aetiology, incidence and morphology of the C-shaped root canal system and its impact on clinical endodontics

    Science.gov (United States)

    Kato, A; Ziegler, A; Higuchi, N; Nakata, K; Nakamura, H; Ohno, N

    2014-01-01

    The C-shaped root canal constitutes an unusual root morphology that can be found primarily in mandibular second permanent molars. Due to the complexity of their structure, C-shaped root canal systems may complicate endodontic interventions. A thorough understanding of root canal morphology is therefore imperative for proper diagnosis and successful treatment. This review aims to summarize current knowledge regarding C-shaped roots and root canals, from basic morphology to advanced endodontic procedures. To this end, a systematic search was conducted using the MEDLINE, BIOSIS, Cochrane Library, EMBASE, Google Scholar, Web of Science, PLoS and BioMed Central databases, and many rarely cited articles were included. Furthermore, four interactive 3D models of extracted teeth are introduced that will allow for a better understanding of the complex C-shaped root canal morphology. In addition, the present publication includes an embedded best-practice video showing an exemplary root canal procedure on a tooth with a pronounced C-shaped root canal. The survey of this unusual structure concludes with a number of suggestions concerning future research efforts. PMID:24483229

  8. Innovative 'Artificial Mussels' technology for assessing spatial and temporal distribution of metals in Goulburn-Murray catchments waterways, Victoria, Australia: effects of climate variability (dry vs. wet years).

    Science.gov (United States)

    Kibria, Golam; Lau, T C; Wu, Rudolf

    2012-12-01

    The "Artificial mussel" (AM), a novel passive sampling technology, was used for the first time in Australia in freshwater to monitor and assess the risk of trace metals (Cd, Cu, Hg, Pb, and Zn). AMs were deployed at 10 sites within the Goulburn-Murray Water catchments, Victoria, Australia during a dry year (2009-2010) and a wet year (2010-2011). Our results showed that the AMs accumulated all the five metals. Cd, Pb, Hg were detected during the wet year but below detection limits during the dry year. At some sites close to orchards, vine yards and farming areas, elevated levels of Cu were clearly evident during the dry year, while elevated levels of Zn were found during the wet year; the Cu indicates localized inputs from the agricultural application of copper fungicide. The impacts from old mines were significantly less compared 'hot spots'. Our study demonstrated that climate variability (dry, wet years) can influence the metal inputs to waterways via different transport pathways. Using the AMs, we were able to identify various 'hot spots' of heavy metals, which may pose a potential risk to aquatic ecosystems (sub-lethal effects to fish) and public (via food chain metal bioaccumulation and biomagnification) in the Goulburn-Murray Water catchments. The State Protection Policy exempted artificial channels and drains from protection of beneficial use (including protection of aquatic ecosystems) and majority of sites ('hot spots') were located within artificial irrigation channels. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Fish and Aquatic Invertebrate Communities in Waterways, and Contaminants in Fish, at the Barataria Preserve of Jean Lafitte National Historical Park and Preserve, Louisiana, 1999-2000

    Science.gov (United States)

    Swarzenski, Christopher M.; Mize, Scott V.; Thompson, Bruce A.; Peterson, Gary W.

    2004-01-01

    Fish and aquatic invertebrate communities in waterways of the Barataria Preserve of Jean Lafitte National Historical Park and Preserve, Louisiana, were surveyed from 1999 to 2000. An inventory of fish in the Barataria Preserve was established, and concentrations of selected organochlorine pesticides, polychlorinated biphenyls, and trace elements; iron; and manganese in fish tissue for selected species were determined. The fish and aquatic invertebrate sampling completed for this study indicated that abundant and diverse communities are present in the Barataria Preserve. Thirty-two species of fish were identified in the Barataria Preserve during this survey. The total number of species identified in a single sampling ranged from 20 to 26. Most of the fish sampled are designated as intermediate in their tolerance to poor water quality. Three species of fish designated as tolerant (common carp, Cyprinus carpio; golden shiner, Notemigonus crysoleucas; and yellow bullhead, Ameiurus natalis), and one as intolerant (lake chubsucker, Erymizon sucetta), were identified. In November 1999, the average total weight of all fish collected by boat-mounted electroshocker from a single site was about 35,000 grams; in May and July 1999, the average total weight was between 9,000 and 10,000 grams. The contribution of spotted gar (Lepisosteus oculatus) to the total weight of the fish averaged between 38 and 41 percent among the three sample periods. Members of the sunfish family (Centrarchidae) contributed between 18 and 28 percent of the total weight. For each sampling period, 60 to 83 percent of the total weight from the sunfish family was contributed by bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides). Aquatic invertebrates were sampled at three sites. Most aquatic invertebrates identified were freshwater species, but some were brackish-water and marine species. About 234,000 organisms were identified and enumerated from the richest-targeted habitat (RTH

  10. Visual and quantitative assessment of lateral lumbar spinal canal stenosis with magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sipola, Petri; Vanninen, Ritva; Manninen, Hannu (Univ. of Eastern Finland, Faculty of Health Sciences, School of Medicine, Inst. of Clinical Medicine, Dept. of Clinical Radiology, Kuopio (Finland); Kuopio Univ. Hospital, Clinical Imaging Centre, Dept. of Clinical Radiology, Kuopio (Finland)), email: petri.sipola@kuh.fi; Leinonen, Ville (Kuopio Univ. Hospital, Dept. of Neurosurgery, Kuopio (Finland)); Niemelaeinen, Riikka (Kuopio Univ. Hospital, Clinical Imaging Centre, Dept. of Clinical Radiology, Kuopio (Finland); Faculty of Rehabilitation Medicine, Univ. of Alberta, Edmonton, Alberta (Canada)); Aalto, Timo (Kyyhkylae Rehabilitation Center and Hospital, Mikkeli (Finland)); Airaksinen, Olavi (Kuopio Univ. Hospital, Dept. of Physical and Rehabilitation Medicine and Univ. of Eastern Finland, Faculty of Health Sciences, School of Medicine, Inst. of Clinical Medicine, Kuopio (Finland)); Battie, Michele C. (Faculty of Rehabilitation Medicine, Univ. of Alberta, Edmonton, Alberta (Canada))

    2011-11-15

    Background. Lateral lumbar spinal canal stenosis is a common etiology of lumbar radicular symptoms. Quantitative measurements have commonly demonstrated better repeatability than visual assessments. We are not aware of any studies examining the repeatability of quantitative assessment of the lateral canal. Purpose. To evaluate the repeatability of visual assessments and newly developed quantitative measurements of lateral lumbar spinal canal stenosis using magnetic resonance imaging (MRI). Material and Methods. Twenty-eight patients with lateral lumbar spinal canal stenosis or prior spinal surgery with recurrent symptoms were imaged with MRI. A radiologist, a neurosurgeon and a spine research trainee graded visually and quantitatively subarticular (n = 188) and foraminal zones (n = 260) of the lateral spinal canal. Quantitative measurements included the minimal subarticular width and the cross-sectional area of the foramen. Results. The repeatability of visual assessment at the subarticular zone and foraminal zones between raters varied from 0.45-0.59 and 0.42-0.53, respectively. Similarly, the intraclass correlation coefficients for the quantitative measurements varied from 0.67-0.71 and 0.66-0.76, respectively. The intra-rater repeatability for the visual assessments of the subarticular and foraminal zones was 0.70 and 0.62, respectively, while the corresponding intraclass correlation coefficients for quantitative measurements were 0.83 and 0.81, respectively. Conclusion. Inter-rater repeatability of visual assessments of lateral stenosis is moderate, whereas quantitative measurements of both subarticular width and the cross-sectional area of the foramen have substantial reproducibility and may be particularly useful for longitudinal studies and research purposes. The clinical value of these parameters requires further study

  11. A new grading system of lumbar central canal stenosis on MRI: an easy and reliable method

    Energy Technology Data Exchange (ETDEWEB)

    Guen, Young Lee; Joon, Woo Lee; Hee, Seok Choi; Kyoung-Jin, Oh; Heung, Sik Kang [Seoul National University Bundang Hospital, Department of Radiology, Seongnam-si, Gyeonggi-do (Korea, Republic of)

    2011-08-15

    To introduce a new grading system of lumbar central canal stenosis, evaluate its reliabilities, and compare it to the cross-sectional area and anterior-posterior diameter of the dural sac. Lumbar central canal stenosis is defined as obliteration of the anterior CSF space in front of the cauda equina. Four musculoskeletal radiologists independently graded lumbar central canal stenosis by this new grading system based on separation degree of the cauda equina on T2-weighted axial images (grade 0 = no lumbar stenosis without obliteration of anterior CSF space; grade 1 = mild stenosis with separation of all cauda equina; grade 2 = moderate stenosis with some cauda equina aggregated; and grade 3 = severe stenosis with none of the cauda equina separated) in 81 patients to determine inter- and intra-reader reliability. One radiologist measured cross-sectional areas and anterior-posterior diameters and compared these to lumbar central canal stenosis grades. Inter-reader reliabilities were substantial to almost perfect (ICC reliability = 0.730-0.953). Intra-reader reliability was almost perfect (kappa value = 0.863-0.900). Cross-sectional areas and anterior-posterior diameters were different according to grades at all levels (p = 0.000-0.049), except between grades 2 and 3 of L2-3. At L5-S1, only anterior-posterior diameter was different between grades 0 and 1 (p = 0.005) and between grades 0 and 2 (p = 0.022). This new grading system may be helpful to clinicians for simple and practical evaluation of lumbar central canal stenosis and for communicating with each other. (orig.)

  12. Lateral Semicircular Canal Asymmetry in Idiopathic Scoliosis: An Early Link between Biomechanical, Hormonal and Neurosensory Theories?

    Science.gov (United States)

    Hitier, Martin; Hamon, Michèle; Denise, Pierre; Lacoudre, Julien; Thenint, Marie-Aude; Mallet, Jean-François; Moreau, Sylvain; Quarck, Gaëlle

    2015-01-01

    Introduction Despite its high incidence and severe morbidity, the physiopathogenesis of adolescent idiopathic scoliosis (AIS) is still unknown. Here, we looked for early anomalies in AIS which are likely to be the cause of spinal deformity and could also be targeted by early treatments. We focused on the vestibular system, which is suspected of acting in AIS pathogenesis and which exhibits an end organ with size and shape fixed before birth. We hypothesize that, in adolescents with idiopathic scoliosis, vestibular morphological anomalies were already present at birth and could possibly have caused other abnormalities. Materials and Methods The vestibular organ of 18 adolescents with AIS and 9 controls were evaluated with MRI in a prospective case controlled study. We studied lateral semicircular canal orientation and the three semicircular canal positions relative to the midline. Lateral semicircular canal function was also evaluated by vestibulonystagmography after bithermal caloric stimulation. Results The left lateral semicircular canal was more vertical and further from the midline in AIS (p = 0.01) and these two parameters were highly correlated (r = -0.6; p = 0.02). These morphological anomalies were associated with functional anomalies in AIS (lower excitability, higher canal paresis), but were not significantly different from controls (p>0.05). Conclusion Adolescents with idiopathic scoliosis exhibit morphological vestibular asymmetry, probably determined well before birth. Since the vestibular system influences the vestibulospinal pathway, the hypothalamus, and the cerebellum, this indicates that the vestibular system is a possible cause of later morphological, hormonal and neurosensory anomalies observed in AIS. Moreover, the simple lateral SCC MRI measurement demonstrated here could be used for early detection of AIS, selection of children for close follow-up, and initiation of preventive treatment before spinal deformity occurs. PMID:26186348

  13. [Measurements of mechanical properties and morphology of root canal in maxillary primary anterior teeth].

    Science.gov (United States)

    Jia, Hu; He, Liu; Qing, Cai; Xuliang, Deng

    2017-08-01

    Objective This study aimed to measure the taper and diameter of root canal, as well as the elastic modulus and hardness in the root dentin of maxillary primary anterior teeth. Methods Patients under general anesthesia who needed root canal therapy in the maxillary primary anterior teeth were selected. Silicone impression material was used to take impressions. The impressions were scanned, and the taper and diameter of root canal were measured. Maxillary primary anterior teeth were collected in vitro. The elastic modulus and hardness of root dentin was tested. Results A total of 74 silicone impressions were obtained. The mean tapers of primary incisor teeth, primary lateral incisor teeth, and primary canine teeth were 0.106, 0.185, and 0.098, respectively. The mean diameters of the root canal 5 mm below the cementum-enamel junction (CEJ) were 1.267, 0.860, and 1.429 mm, respectively. The elastic modulus and hardness of root dentin were measured in 10 primary anterior teeth in vitro. The range of elastic modulus was 19.919-25.017 GPa. The range of hardness was 0.867-1.082 GPa. Conclusion The root canal post used in primary anterior teeth can be produced by the following data: taper of primary incisor teeth and primary canine teeth, 0.1; diameters of their tips, 1.2 mm and 1.4 mm, respectively; taper of primary lateral incisor teeth, 0.2; diameter of their tips, 0.8 mm; range of elastic modulus, 20-25 GPa; and range of hardness, 0.87-1.08 GPa.

  14. Hand and ultrasonic instrumentation for orthograde root canal treatment of permanent teeth

    Directory of Open Access Journals (Sweden)

    Vinícius Pedrazzi

    2010-06-01

    Full Text Available Root canal treatment is a frequently performed dental procedure and is carried out on teeth in which irreversible pulpitis has led to necrosis of the dental pulp. Removal of the necrotic tissue remnants and cleaning and shaping of the root canal are important phases of root canal treatment. Treatment options include the use of hand and rotary instruments and methods using ultrasonic or sonic equipment. OBJECTIVES: The objectives of this systematic review of randomized controlled trials were to determine the relative clinical effectiveness of hand instrumentation versus ultrasonic instrumentation alone or in conjunction with hand instrumentation for orthograde root canal treatment of permanent teeth. MATERIAL AND METHODS: The search strategy retrieved 226 references from the Cochrane Oral Health Group Trials Register (7, the Cochrane Central Register of Controlled Trials (CENTRAL (12, MEDLINE (192, EMBASE (8 and LILACS (7. No language restriction was applied. The last electronic search was conducted on December 13th, 2007. Screening of eligible studies was conducted in duplicate and independently. RESULTS: Results were to be expressed as fixed-effect or random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confdence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. No eligible randomized controlled trials were identifed. CONCLUSIONS: This review illustrates the current lack of published or ongoing randomized controlled trials and the unavailability of high-level evidence based on clinically relevant outcomes referring to the effectiveness of ultrasonic instrumentation used alone or as an adjunct to hand instrumentation for orthograde root canal treatment. In the absence of reliable research-based evidence, clinicians should base their decisions on clinical experience, individual circumstances and in conjunction with patients

  15. Positional relationship between mandibular third molar and mandibular canal in cone beam computed tomographs

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Su Kyung; Lee, Ji Un; Kim, Kyoung A; Koh, Kwang Joon [Chonbuk National Univ. Hospital, Chonju (Korea, Republic of)

    2007-12-15

    To provide diagnostic information by evaluation of the positional relationship between the mandibular third molar and the mandibular canal. Eighty-nine mandibular third molars were classified as mesioangular, horizontal, vertical, distoangular groups. The distances between the mandibular third molar and the mandibular canal were measured in cone-beam computed tomographs. The height and width ratios of distances from the mandibular third molar and the mandibular canal to the mandibular inferior border and to the lingual cortical plate were calculated. The vertical and buccolingual distances between the mandibular third molar and the mandibular canal were 0.03 mm, 2.96 mm in the mesioangular, 0.37 mm, 3.38 ,, in the horizontal, -1.50 mm, 1.38 mm in the vertical, -1.10 mm, 4.20 mm in the distoangular group. There were significant differences in vertical (P<0.05), but not in buccolingual (P>0.05). The height and width ratios of distances on the mandibular third molar were 47.1%, 36.1% in the mesioangular, 47.4%, 34.4% in the horizontal, 37.0%, 46.7% in the vertical, 40.9%, 37.4% in the distoangular group. There were significant differences between the mesioangular and the vertical group, and the horizontal and the vertical group in height ratio (P>0.05). The mesioangular group showed the nearest distance between the mandibular third molar and the mandibular canal vertically. The root apex of the mandibular third molar was positioned more buccally in the vertical group than in the mesioangular group.

  16. Stretching morphogenesis of the roof plate and formation of the central canal.

    Directory of Open Access Journals (Sweden)

    Igor Kondrychyn

    Full Text Available BACKGROUND: Neurulation is driven by apical constriction of actomyosin cytoskeleton resulting in conversion of the primitive lumen into the central canal in a mechanism driven by F-actin constriction, cell overcrowding and buildup of axonal tracts. The roof plate of the neural tube acts as the dorsal morphogenetic center and boundary preventing midline crossing by neural cells and axons. METHODOLOGY/PRINCIPAL FINDINGS: The roof plate zebrafish transgenics expressing cytosolic GFP were used to study and describe development of this structure in vivo for a first time ever. The conversion of the primitive lumen into the central canal causes significant morphogenetic changes of neuroepithelial cells in the dorsal neural tube. We demonstrated that the roof plate cells stretch along the D-V axis in parallel with conversion of the primitive lumen into central canal and its ventral displacement. Importantly, the stretching of the roof plate is well-coordinated along the whole spinal cord and the roof plate cells extend 3× in length to cover 2/3 of the neural tube diameter. This process involves the visco-elastic extension of the roof place cytoskeleton and depends on activity of Zic6 and the Rho-associated kinase (Rock. In contrast, stretching of the floor plate is much less extensive. CONCLUSIONS/SIGNIFICANCE: The extension of the roof plate requires its attachment to the apical complex of proteins at the surface of the central canal, which depends on activity of Zic6 and Rock. The D-V extension of the roof plate may change a range and distribution of morphogens it produces. The resistance of the roof plate cytoskeleton attenuates ventral displacement of the central canal in illustration of the novel mechanical role of the roof plate during development of the body axis.

  17. Efficacy of manual and mechanical instrumentation techniques for removal of overextended root canal filling material.

    Science.gov (United States)

    Kesim, B; Üstün, Y; Aslan, T; Topçuoğlu, H S; Şahin, S; Ulusan, Ö

    2017-06-01

    To compare the efficacy of manual and mechanical instrumentation techniques, including ProTaper Universal retreatment system, Mtwo retreatment system, Reciproc system, and Hedström files, regarding removal of overextended root canal filling material. Eighty extracted human mandibular premolar teeth were prepared at the apical foramen level using Revo-S rotary files and subsequently obturated. The root canal filling material was deliberately extruded from the apex. Samples were transferred to glass vials that simulated the periapical area. Eighty samples of overfilled teeth were randomly assigned to four equal groups (n = 20) for removal of the root filling material with ProTaper Universal retreatment files (Group 1), Mtwo retreatment files (Group 2), Reciproc system (Group 3), and hand files (Group 4). Removal of the root canal filling material and additional preparation were performed by individual instruments from each different system up to a #40 size. The external apical surface of the teeth and the surrounding glass vials were checked using a dental operation microscope with ×12.5 magnification. Samples were divided into two groups based on whether removal of the overextended root canal filling material was successful or not. The Fisher's exact test was used to detect any significant difference between the groups (α = 0.05). The success rate for removal of overextended gutta-percha was greater for the Mtwo (30%) and hand files (30%) compared with the ProTaper (20%) and Reciproc (10%). However, no significant statistical differences existed among the experimental groups (P > 0.05). This study demonstrated that all tested systems had similar efficacy in removing overextended root canal filling material.

  18. Analysis of water resources engineering and economics of diversion canal No.1 (DR.1

    Directory of Open Access Journals (Sweden)

    Pornpinatepong, K.

    2005-07-01

    Full Text Available To prevent flooding of Hat Yai city, diversion of excess water from the U-taphao river which flows to the town is contemplated. Diversion canal No.1 (DR.1, located at the west of the U-taphao river, is designed based on a 25-year-flood period. For a proper economic analysis, two scenarios have been introduced and compared: (A drain directly towards the Songkhla lake by means of a full- ength new canal (21.34 km, and (B use the Klong Bang Klam as a bypass, reducing the length of the canal to 13.8 km. The collected data and the model results indicate that the two cases practically provide the same hydraulic efficiency. Cost-benefit analysis has been performed on the two alternative scenarios (A and B. With the discount rate of 12 percent, the results indicated that the case A would be beneficial if the flood occurs in the first year of the project and the net present value (NPV of the case B will be positive from year 1 to 4 (2006-2009. For the lower discount rate of 6 percent, the benefit of the case B prolongs an additional 3 years (2010-2012. For later years (the remaining 17 years of the case B, negative results are predicted. This implies that diversion canal No.1 (DR.1 may not be worth the money for the flood protection. For a proper decision by the authorities, the socio- economics and environmental impact aspects should be brought into account and the diversion canal No.1 (DR.1 needs to be reviewed.

  19. Fracture strength of endodontically treated teeth with flared root canals and restored with different post systems.

    Science.gov (United States)

    Maccari, Paulo César; Cosme, Dúcia Caldas; Oshima, Hugo Mitsuo; Burnett, Luiz Henrique; Shinkai, Rosemary Sadami

    2007-01-01

    Many post systems are available to clinicians, yet no consensus exists about which one is better in restoring endodontically treated teeth. This study evaluated the fracture strength of teeth with flared canals and restored with two fiber-reinforced resin systems (glass fiber: FRC Postec [Ivoclar Vivadent, Schaan, Liechtenstein]; quartz fiber: D.T. Light-Post [Bisco Dental Products, Schaumburg, IL, USA]), and one custom cast base metal (Ni-Cr) post and core system. Thirty anterior teeth had their crowns removed below the cemento-enamel junction and were endodontically treated. The canals were prepared for post fixation, and the canal walls were flared using a taper diamond bur. The prepared roots were randomly divided into three groups according to the post system. All posts were cemented with an adhesive resin cement. For the fiber-reinforced resin posts, cores were built up using microhybrid composite. Metallic crowns were luted using zinc phosphate cement. Specimens were loaded at 45 degrees in a universal testing machine at a crosshead speed of 0.5 mm/min until failure. The mode of failure was classified as repairable or nonrepairable. Teeth restored with cast posts had fracture strength twice that of teeth restored with resin posts. Fiber-reinforced resin posts failed at a compressive force comparable to clinical conditions, but all failures were repairable. Fracture strength and mode of failure in anterior teeth with flared canals varied according to the type of post used to support a crown. Under the conditions of this study, cast posts are preferable to restore endodontically treated teeth with flared canals and no ferrule.

  20. 75 FR 4693 - Drawbridge Operation Regulation; Inner Harbor Navigational Canal, New Orleans, LA

    Science.gov (United States)

    2010-01-29

    ... Canal, mile 4.6, at New Orleans, LA. The deviation is necessary to ensure the safety of pedestrians as they bike across the bridge for the Ochsner Ironman 70.3 New Orleans event. This deviation allows the... the bridge as part of the 56 mile bike course. Navigation on the waterway consists mainly of tugs with...

  1. Ancient Irrigation Canals Mapped from Corona Imageries and Their Implications in Juyan Oasis along the Silk Road

    Directory of Open Access Journals (Sweden)

    Ningke Hu

    2017-07-01

    Full Text Available Historical records and archaeological discoveries have shown that prosperous agricultural activities developed in the ancient Juyan Oasis of northwestern China, an important oasis that once flourished on the ancient Silk Road. However, how the irrigation canals were distributed in historical time was unknown. Here, we identified and mapped the spatial distribution of ancient abandoned irrigation canals that were built using CORONA photographs and field inspections. This work found that ancient irrigation canals are large-scale and distributed throughout the desertified environment, with three hierarchical organization of first-, second-, and third-order irrigation canals (the total length of the first- and second-order-irrigation canals is dramatically more than 392 km. This study further indicates that ancient irrigation methods and modern irrigation systems in arid regions of China share the same basic irrigation design. New visual and fine-scale evidence and spatial distribution of irrigation canals are provided to illustrate the development of the ancient irrigated agriculture that occurred in the Juyan Oasis. This work is useful for readers who are interested in the construction and organization approaches of irrigation canals used in ancient irrigated agriculture in arid regions. It also has implications for how ancient people balance the relationships between human needs and the eco-environment using reasonable water management methods, especially for decision-making in the efficient usage of limited water resources in the arid inland river basin.

  2. Comparative study of the macroscopic finding, conventional tomographic imaging, and computed tomographic imaging in locating the mandibular canal

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hang Moon; You, Dong Soo [Dept. of Oral and Maxillofacial Radiology, Graduate School, Seoul National University, Seoul (Korea, Republic of)

    1995-08-15

    The purpose of this study was comparison of conventional tomography with reformatted computed tomography for dental implant in locating the mandibular canal. Five dogs were used and after conventional tomographs and fitted computed tomographs were taken, four dentist traced all films. Mandibles were sectioned with 2 mm slice thickness and the sections were then radiographed (contact radiography). Each radiograpic image was traced and linear measurements were made from mandibular canal to alveolar crest, buccal cortex, lingual cortex, and inferior border. The following results were obtained; 1. Reformatted computed tomographs were exacter than conventional tomography by alveolar crest to canal length of -0.6 mm difference between real values and radiographs 2. The average measurements of buccal cortex to mandibular canal width and lingual cortex to mandibular canal width of conventional tomographs were exacter than reformatted computed tomographs, but standard deviations were higher than reformatted computed tomographs. 3. Standard deviations of reformatted computed tomographs were lower than conventional tomographs at all comparing sites 4. At reformatted computed tomography 62.5% of the measurements performed were within {+-}1 mm of the true value, and at conventional tomography 24.1% were. 5. Mandibular canal invisibility was 0.8% at reformatted computed tomography and 9.2% at conventional tomography. Reformatted computed tomography has been shown to be more useful radiographic technique for assessment of the mandibular canal than conventional tomography.

  3. Endodontic Treatment of Maxillary Premolar with Three Root Canals Using Optical Microscope and NiTi Rotatory Files System.

    Science.gov (United States)

    Relvas, João Bosco Formiga; de Carvalho, Fredsom Marcio Acris; Marques, André Augusto Franco; Sponchiado, Emílio Carlos; Garcia, Lucas da Fonseca Roberti

    2013-01-01

    The aim of the study was to report a clinical case of endodontic treatment of a maxillary first premolar with three root canals using an optical microscope and rotary instrumentation technique. The main complaint of the patient, a 16-year-old girl, was pain in tooth 14. After clinical and radiographic examination, irreversible pulpitis was diagnosed. An alteration in the middle third of the pulp chamber radiographically observed suggested the presence of three root canals. Pulp chamber access and initial catheterization using size number 10 K-files were performed. The optical microscope and radiographic examination were used to confirm the presence of three root canals. PathFiles #13, #16, and #19 were used to perform catheterization and ProTaper files S1 and S2 for cervical preparation. Apical preparation was performed using F1 file in the buccal canals and F2 in the palatal canal up to the working length. The root canals were filled with Endofill sealer by thermal compaction technique using McSpadden #50. The case has been receiving follow-up for 12 months and no painful symptomatology or periapical lesions have been found. The use of technological tools was able to assist the endodontic treatment of teeth with complex internal anatomy, such as three-canal premolars.

  4. A Compositional Study Of The Phytoplankton Of Lake Drummond And The Rivers And Canals That Drain The Dismal Swamp

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A six-week study of the phytoplankton in Lake Drummond and the canals and river which drain the Dismal Swamp resulted in the identification of 110 species. These...

  5. Morphological analysis of the cervical spinal canal, dural tube and spinal cord in normal individuals using CT myelography

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, H. [Department of Orthopaedic and Spinal Surgery, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466 (Japan); Ohmori, K. [Department of Orthopaedic and Spinal Surgery, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466 (Japan); Takatsu, T. [Department of Orthopaedic and Spinal Surgery, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466 (Japan); Teramoto, T. [Department of Orthopaedic and Spinal Surgery, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466 (Japan); Ishida, Y. [Department of Orthopaedic and Spinal Surgery, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466 (Japan); Suzuki, K. [Department of Orthopaedic and Spinal Surgery, Nagoya Daini Red Cross Hospital, 2-9 Myoken-cho, Showa-ku, Nagoya 466 (Japan)

    1996-02-01

    To verify the conventional concept of ``developmental stenosis of the cervical spinal canal``, we performed a morphological analysis of the relations of the cervical spinal canal, dural tube and spinal cord in normal individuals. The sagittal diameter, area and circularity of the three structures, and the dispersion of each parameter, were examined on axial sections of CT myelograms of 36 normal subjects. The spinal canal was narrowest at C4, followed by C5, while the spinal cord was largest at C4/5. The area and circularity of the cervical spinal cord were not significantly correlated with any parameter of the spinal canal nor with the sagittal diameter and area of the dural tube at any level examined, and the spinal cord showed less individual variation than the bony canal. Compression of the spinal cord might be expected whenever the sagittal diameter of the spinal canal is below the lower limit of normal, that is about 12 mm on plain radiographs. Thus, we concluded that the concept of ``developmental stenosis of the cervical spinal canal`` was reasonable and acceptable. (orig.). With 2 figs., 3 tabs.

  6. Clinical and Radiographic Evaluation of Procedural Accidents and Errors during Root Canal Therapy

    OpenAIRE

    Mozayeni, Mohammad Ali; Asnaashari, Mohammad; Modaresi, Seyed Jalil

    2006-01-01

    INTRODUCTION: Root canal therapy (RCT)_like other dental practices_ can be accompanied with some accidents or unpredictable conditions that are called "procedural accidents". Having the knowledge about these accidents and their etiology is essential to have RCT completion and to prevent the repeat of these accidents. This study was designed to evaluate accidents occurring during RCT in patients referred to endodontic department of Shaheed Beheshti dental school during 2002. MATERIALS AND METH...

  7. Effect of Zingiber officinale and propolis on microorganisms and endotoxins in root canals

    Directory of Open Access Journals (Sweden)

    Lilian Eiko MAEKAWA

    2013-03-01

    Full Text Available The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO and ginger (GIN extracts, calcium hydroxide (CH, chlorhexidine (CLX gel and their combinations as ICMs (ICMs against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals. Material and Methods After 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal. Results and Conclusion After analysis of results and application of the Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success.

  8. Phenotype and Genotype of Enterococcus faecalis Isolated form Root Canal and Saliva of Primary Endodontic Patients

    Directory of Open Access Journals (Sweden)

    Zaki Mubarak

    2016-04-01

    Full Text Available This study was carried out to investigate the phenotype and genotype of E. faecalis isolated from the root canal and saliva of primary endodontic patients with periapical lesions. Eighteen adult male and female individuals suffering from primary endodontic infection, either had or had not periapical lesions, were involved in this study. Root canal scraping and saliva were collected from each subject and used for bacterial quantitation using a real-time polymerase chain reaction (RT-PCR. Enterococci were isolated using ChromAgar medium and then identified using both biochemical (Gram staining and catalase tests and molecular biology (conventional PCR methods. Gelatinase activity, polysaccharide capsul profile and mRNA ace expression level were determined using microbiological, biochemical and molecular biology approach, respectively.  Genotype of E. faecalis was determined based on nucleotide sequence of ace and gelE genes analyzed using web-based 3730xl DNA Analyze software. The results showed that high proportion of E. faecalis found in both root canal and saliva of is related to the incidence of periapical lessions in the primary endodontic patients. This is contrast to the insignificant relationship found between Cps polymorphism, gelatinase activity, and mRNA ace expression with periapical lesions in the patients, respectively.DOI: 10.14693/jdi.v23i1.960

  9. Investigating driver willingness to drive through flooded waterways.

    Science.gov (United States)

    Pearson, Marti; Hamilton, Kyra

    2014-11-01

    Approximately 40% of all drowning deaths involve a motor vehicle. Regardless of its significance as a cause of flood-related mortality, there is continued prevalence of driving through flooded waterways in Australia and worldwide. We aimed to understand the motivational determinates of driving through flooded waterways in low and high-risk scenarios by utilizing an augmented theory of planned behaviour (TPB) with behavioural willingness as the outcome variable as well as the influence of additional predictors; namely perceived risk and past behaviour. Participants (n=174; Mage=27.43, SD=10.76) answered standard TPB-based questions in regards to attitudes, subjective norm, and perceived behavioural control (PBC), as well as additional variables of perceived risk (i.e., perceived susceptibility and perceived severity) and past behaviour. Support was found for the augmented TPB as attitude, subjective norm, and PBC predicted behavioural willingness. Support was also found for perceived severity in the high-risk but not the low-risk scenario. No support was found for perceived susceptibility. Past behaviour emerged as a significant predictor of willingness in the low and high-risk scenario. The findings provide support for an augmented TPB in understanding individuals' willingness to drive through flooded waterways, suggesting that a multi-strategy approach may be critical in attempts to reduce the incidence of such risky driving behaviour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. A cellular automaton model for ship traffic flow in waterways

    Science.gov (United States)

    Qi, Le; Zheng, Zhongyi; Gang, Longhui

    2017-04-01

    With the development of marine traffic, waterways become congested and more complicated traffic phenomena in ship traffic flow are observed. It is important and necessary to build a ship traffic flow model based on cellular automata (CAs) to study the phenomena and improve marine transportation efficiency and safety. Spatial discretization rules for waterways and update rules for ship movement are two important issues that are very different from vehicle traffic. To solve these issues, a CA model for ship traffic flow, called a spatial-logical mapping (SLM) model, is presented. In this model, the spatial discretization rules are improved by adding a mapping rule. And the dynamic ship domain model is considered in the update rules to describe ships' interaction more exactly. Take the ship traffic flow in the Singapore Strait for example, some simulations were carried out and compared. The simulations show that the SLM model could avoid ship pseudo lane-change efficiently, which is caused by traditional spatial discretization rules. The ship velocity change in the SLM model is consistent with the measured data. At finally, from the fundamental diagram, the relationship between traffic ability and the lengths of ships is explored. The number of ships in the waterway declines when the proportion of large ships increases.

  11. [Investigation of root and canal morphology of human primary mandibular second molar by cone-beam CT].

    Science.gov (United States)

    Yang, Chan; Yang, Ran; Zou, Jing

    2013-06-01

    To investigate the root and canal morphology of primary mandibular second molars in a Chinese population by cone-beam CT(CBCT). A total of 305 CBCT images of 305 children aged 4-8 years were collected, who came to West China Dental Hospital from October, 2011 to March, 2012 due to supernumerary teeth, dental trauma, orthodontic treatment or oral maxillofacial tumor. Primary mandibular second molars which roots were full developed, without periapical infection or apical root resorption were enrolled. All the images were analyzed by two researchers. The data were statistically analyzed by software SPSS 19.0. Four hundred and thirty-seven primary mandibular second molars(PMSM) showed single mesial root except one which had two. Three hundred and twenty-five (74.4%) teeth had one distal root, 111(25.4%) teeth had two and one had three. There were 424(97.0%) teeth which had two mesial canals and 13(3.0%) had one.One hundred and three(23.6%) teeth had one distal root with one canal, 222(50.8%) had one distal root with two canals, 106(24.3%) had two distal roots with two canals, 5(1.1%) had two roots with three canals and 1(0.2%) had three roots with three canals. The root canal system of PMSM had ten variants in this study. The prevalence of three-rooted PMSM had significant differences from different genders (P = 0.000) and different sides (P = 0.028). Majority of primary mandibular second molars had two roots, and the minority had three roots. The prevalence of three-rooted molars in males were higher than that in females. Mesial and distal roots of primary mandibular second molars often had two canals.

  12. In vitro evaluation of root canal preparation with two rotary instrument systems - Pro Taper and Hero Shaper.

    Science.gov (United States)

    Pentelescu, Carola; Colceriu, Loredana; Pastrav, Ovidiu; Culic, Carina; Chisnoiu, Radu

    2015-01-01

    The purpose of this study was to compare several parameters of root canal preparation using two different rotary Nickel-Titanium instruments: Pro-Taper (Dentsply Maillefer, Ballagigues, Switzerland) and Hero-Shaper (Micro Mega, Besancon, France). Twelve extracted maxillary premolars were randomly divided into two groups and embedded into a muffle system. All root canals were prepared to size 25 using Pro-Taper or Hero-Shaper rotary instruments. The following parameters were evaluated: root canal form, centering capacity of the instrument, the presence of residual dentinal debris and smear layer on the root canal walls, working time and the occurrence of intraoperative accidents. Statistical analysis was performed using the chi(2) test (p=0.05). The majority of the root canals prepared with Hero Shaper (88.89%) and ProTaper (77.78%) showed a round or oval cross-section postoperatively. Superposition of pre- and postoperative photographs of the cross-sections showed that for the coronal third of the root canals the Hero Shaper performed in a superior manner, while for the apical third better results were obtained with the Pro Taper system. Cleanliness of the root canal walls was investigated under the SEM, in the middle third of the canal, using a five-score system for debris and smear layer. For debris Hero Shaper and Pro Taper rotary systems achieved 66.67% and 50% scores of 1 or 2, respectively. The results for the smear layer were similar: cleaner root canal walls were found after preparation with Hero Shaper (66.67% scores 1, 2), followed by Pro Taper (50%). Mean working time was shorter for Hero Shaper (124s) than for Pro Taper (184s); the difference was not significant. Within the limits of this study, both systems had almost the same cleaning ability and excellent centering capacity.

  13. Micro-CT assessment of changes in the morphology and position of the immature mandibular canal during early growth.

    Science.gov (United States)

    Hutchinson, E F; Florentino, G; Hoffman, J; Kramer, B

    2017-02-01

    The mandibular canal contributes to the development and growth of the mandible, as it acts as a conduit for the growing inferior alveolar neurovascular structures. A clear understanding of the canal's pathway is, therefore, important in interpreting the growth pattern of the inferior alveolar neurovascular bundle. This study investigated the position of the mandibular canal within the body of the mandible and its general dimensions within a pediatric collection of mandibles. The sample included 45 mandibles and was subdivided into three: group 1 (30 gestational weeks to birth), group 2 (birth to 12 months), and group 3 (1 to 4 years). Mandibles were scanned using a Nikon XTH 225L micro-CT unit. Scanning conditions ranged between 85 kV/83 µA and 100 kV/100 µA. Measurements included: the maximum width and height of the mandibular canal and distances between the mandibular canal and the relevant surfaces of the mandible. Data analysis included an ANOVA, MANOVA, and principal component analysis. The mandibular canal increased significantly in size from 30 gestational weeks to 12 months relative to the deciduous molar crypts. Postnatally, the mandibular canal increased significantly in height at the level of the second deciduous molar crypt. The canal lies closer to the buccal surface in the region of the first and second deciduous molar teeth. The consistency in the positioning of the mandibular canal within the body of the mandible may assist in predicting the occurrence of aberrant growth patterns, particularly during the initial stages of growth.

  14. Effect of Zingiber officinale and propolis on microorganisms and endotoxins in root canals.

    Science.gov (United States)

    Maekawa, Lilian Eiko; Valera, Marcia Carneiro; Oliveira, Luciane Dias de; Carvalho, Cláudio Antonio Talge; Camargo, Carlos Henrique Ribeiro; Jorge, Antonio Olavo Cardoso

    2013-01-01

    The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO) and ginger (GIN) extracts, calcium hydroxide (CH), chlorhexidine (CLX) gel and their combinations as ICMs (ICMs) against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals. After 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal. After analysis of results and application of the Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success.

  15. Analysis of kinematic, kinetic and electromyographic patterns during root canal preparation with rotary and manual instruments

    Directory of Open Access Journals (Sweden)

    Braulio Pasternak-Júnior

    2012-02-01

    Full Text Available OBJECTIVE: This study assessed the muscular activity during root canal preparation through kinematics, kinetics, and electromyography (EMG. MATERIAL AND METHODS: The operators prepared one canal with RaCe rotary instruments and another with Flexo-files. The kinematics of the major joints was reconstructed using an optoelectronic system and electromyographic responses of the flexor carpi radialis, extensor carpi radialis, brachioradialis, biceps brachii, triceps brachii, middle deltoid, and upper trapezius were recorded. The joint torques of the shoulder, elbow and wrist were calculated using inverse dynamics. In the kinematic analysis, angular movements of the wrist and elbow were classified as low risk factors for work-related musculoskeletal disorders. With respect to the shoulder, the classification was medium-risk. RESULTS: There was no significant difference revealed by the kinetic reports. The EMG results showed that for the middle deltoid and upper trapezius the rotary instrumentation elicited higher values. The flexor carpi radialis and extensor carpi radialis, as well as the brachioradialis showed a higher value with the manual method. CONCLUSION: The muscular recruitment for accomplishment of articular movements for root canal preparation with either the rotary or manual techniques is distinct. Nevertheless, the rotary instrument presented less difficulty in the generation of the joint torque in each articulation, thus, presenting a greater uniformity of joint torques.

  16. Prevalence and nature of fungi in root canal infections: a systematic review and meta-analysis.

    Science.gov (United States)

    Persoon, I F; Crielaard, W; Özok, A R

    2017-11-01

    The role of bacteria in causing apical periodontitis has been widely established, whilst the role of other microorganisms is studied less thoroughly. This systematic review and meta-analysis reviewed the literature for the prevalence and diversity of fungi in root canal infections. An extensive literature search was carried out in the Cochrane databases, EMBASE, MEDLINE, LILACS, SciELO and Web of Science. Additional studies were identified from six endodontic journals, four main endodontic textbooks and references of relevant papers. Selected clinical studies included sampling of necrotic pulps in permanent teeth and microbial analysis of these samples. Studies were critically appraised using the Joanna Briggs Institute Prevalence Critical Appraisal Checklist. Meta-analysis was performed using MetaXL. The screening of 1041 titles and abstracts and full-text reading yielded 54 studies. The overall prevalence of fungi in root canal infections was 7.5% (CI 95%: 3.6-11.8%) in the inverse variance fixed effect heterogeneity model. Candida albicans was the most frequently isolated species. Significant heterogeneity was observed (P nature of fungi in root canal infections. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  17. Action of propolis and medications against Escherichia coli and endotoxin in root canals.

    Science.gov (United States)

    Valera, Marcia Carneiro; da Rosa, Jucely Aparecida; Maekawa, Lilian Eiko; de Oliveira, Luciane Dias; Carvalho, Cláudio Antonio Talge; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2010-10-01

    This study evaluated the action of propolis and intracanal medications against Escherichia coli and endotoxin. Forty-eight dental roots were contaminated with E. coli. The root canals were instrumented with propolis and divided into groups according to the type of intracanal medication: Ca(OH)(2), polymyxin B, or Ca(OH)(2) + 2% chlorhexidine gel. In the control group, saline solution was used without application of intracanal medication. Counts of colony-forming units were carried out and the endotoxin was quantified by the chromogenic Limulus amobocyte lysate assay. The results were evaluated by analysis of variance and the Dunn test (5%). Root canal irrigation with propolis was effective to completely eliminate E. coli and reduce the amount of endotoxins. All intracanal medications contributed to the significant decrease in endotoxins. Only intracanal medications may reduce the amount of endotoxins in the root canals. The greatest efficacy was observed for medications containing Ca(OH)(2). Copyright © 2010. Published by Mosby, Inc.

  18. Magmatic evolution of Panama Canal volcanic rocks: A record of arc processes and tectonic change.

    Directory of Open Access Journals (Sweden)

    David W Farris

    Full Text Available Volcanic rocks along the Panama Canal present a world-class opportunity to examine the relationship between arc magmatism, tectonic forcing, wet and dry magmas, and volcanic structures. Major and trace element geochemistry of Canal volcanic rocks indicate a significant petrologic transition at 21-25 Ma. Oligocene Bas Obispo Fm. rocks have large negative Nb-Ta anomalies, low HREE, fluid mobile element enrichments, a THI of 0.88, and a H2Ocalc of >3 wt. %. In contrast, the Miocene Pedro Miguel and Late Basalt Fm. exhibit reduced Nb-Ta anomalies, flattened REE curves, depleted fluid mobile elements, a THI of 1.45, a H2Ocalc of <1 wt. %, and plot in mid-ocean ridge/back-arc basin fields. Geochemical modeling of Miocene rocks indicates 0.5-0.1 kbar crystallization depths of hot (1100-1190°C magmas in which most compositional diversity can be explained by fractional crystallization (F = 0.5. However, the most silicic lavas (Las Cascadas Fm. require an additional mechanism, and assimilation-fractional-crystallization can reproduce observed compositions at reasonable melt fractions. The Canal volcanic rocks, therefore, change from hydrous basaltic pyroclastic deposits typical of mantle-wedge-derived magmas, to hot, dry bi-modal magmatism at the Oligocene-Miocene boundary. We suggest the primary reason for the change is onset of arc perpendicular extension localized to central Panama. High-resolution mapping along the Panama Canal has revealed a sequence of inward dipping maar-diatreme pyroclastic pipes, large basaltic sills, and bedded silicic ignimbrites and tuff deposits. These volcanic bodies intrude into the sedimentary Canal Basin and are cut by normal and subsequently strike-slip faults. Such pyroclastic pipes and basaltic sills are most common in extensional arc and large igneous province environments. Overall, the change in volcanic edifice form and geochemistry are related to onset of arc perpendicular extension, and are consistent with the

  19. Human tooth and root canal morphology reconstruction using magnetic resonance imaging

    Science.gov (United States)

    DRĂGAN, OANA CARMEN; FĂRCĂŞANU, ALEXANDRU ŞTEFAN; CÂMPIAN, RADU SEPTIMIU; TURCU, ROMULUS VALERIU FLAVIU

    2016-01-01

    Background and aims Visualization of the internal and external root canal morphology is very important for a successful endodontic treatment; however, it seems to be difficult considering the small size of the tooth and the complexity of the root canal system. Film-based or digital conventional radiographic techniques as well as cone beam computed tomography provide limited information on the dental pulp anatomy or have harmful effects. A new non-invasive diagnosis tool is magnetic resonance imaging, due to its ability of imaging both hard and soft tissues. The aim of this study was to demonstrate magnetic resonance imaging to be a useful tool for imaging the anatomic conditions of the external and internal root canal morphology for endodontic purposes. Methods The endodontic system of one freshly extracted wisdom tooth, chosen for its well-known anatomical variations, was mechanically shaped using a hybrid technique. After its preparation, the tooth was immersed into a recipient with saline solution and magnetic resonance imaged immediately. A Bruker Biospec magnetic resonance imaging scanner operated at 7.04 Tesla and based on Avance III radio frequency technology was used. InVesalius software was employed for the 3D reconstruction of the tooth scanned volume. Results The current ex-vivo experiment shows the accurate 3D volume rendered reconstruction of the internal and external morphology of a human extracted and endodontically treated tooth using a dataset of images acquired by magnetic resonance imaging. The external lingual and vestibular views of the tooth as well as the occlusal view of the pulp chamber, the access cavity, the distal canal opening on the pulp chamber floor, the coronal third of the root canals, the degree of root separation and the apical fusion of the two mesial roots, details of the apical region, root canal curvatures, furcal region and interradicular root grooves could be clearly bordered. Conclusions Magnetic resonance imaging offers 3

  20. [The position and course of mandibular canal through mandibular ramus in patients with prognathism].

    Science.gov (United States)

    Ma, Jia; Lu, Li; Song, Cong-Xiao

    2008-04-01

    PUEPOSE: To investigate the position and course of mandibular canal through mandibular ramus in patients with prognathism using computed tomography, and to relate the findings to sagittal split ramus osteotomy, and also to describe the anatomical variability of mandibular canal in order to reduce injuries to the inferior alveolar nerve. The mandibles of 45 patients with skeletal Class III prognathism undergoing sagittal split ramus osteotomy were examined by spiral computed tomography. The region from a plane containing the lowest point of mandibular foramen(base plane 0) to 25 mm below it was measured with 5 mm distance every plane. The following parameters were measured: total thickness of mandible through the center of mandibular canal, thickness of buccal and lingular cortical plate, and narrowest portion of bone marrow space between the outer mandibular canal and both the buccal and lingular cortex. All measurements were analyzed with SPSS 13.0 software package. The thickness of mandible increased from the mandibular formen to mandibular body, there was no statistical difference among the sites with regards to the inner diameter of mandibular canal (F=1.044,P=0.391). The width of bone marrow space at the buccal side was significantly different between 3,4 plane and 0 plane,and the measured widths on the lingual side were significantly increased. The width of the buccal side bone marrow space at each site could be classified into three types, the separate type was most prevalent in this study(n=391 of 456,85.5%), contact and fusion type were 12.71% and 1.54% respectively. There was no significant difference between the left and right side. On average, the mandibular canal is situated more lingually at all sites, and the width of bone marrow space at the buccal side is more narrow at 15-20mm below the mandibular foramen. When the width of marrow space at buccal side is absent, especially the fusion type, it is suggested to select an other procedure rather than

  1. Human tooth and root canal morphology reconstruction using magnetic resonance imaging.

    Science.gov (United States)

    Drăgan, Oana Carmen; Fărcăşanu, Alexandru Ştefan; Câmpian, Radu Septimiu; Turcu, Romulus Valeriu Flaviu

    2016-01-01

    Visualization of the internal and external root canal morphology is very important for a successful endodontic treatment; however, it seems to be difficult considering the small size of the tooth and the complexity of the root canal system. Film-based or digital conventional radiographic techniques as well as cone beam computed tomography provide limited information on the dental pulp anatomy or have harmful effects. A new non-invasive diagnosis tool is magnetic resonance imaging, due to its ability of imaging both hard and soft tissues. The aim of this study was to demonstrate magnetic resonance imaging to be a useful tool for imaging the anatomic conditions of the external and internal root canal morphology for endodontic purposes. The endodontic system of one freshly extracted wisdom tooth, chosen for its well-known anatomical variations, was mechanically shaped using a hybrid technique. After its preparation, the tooth was immersed into a recipient with saline solution and magnetic resonance imaged immediately. A Bruker Biospec magnetic resonance imaging scanner operated at 7.04 Tesla and based on Avance III radio frequency technology was used. InVesalius software was employed for the 3D reconstruction of the tooth scanned volume. The current ex-vivo experiment shows the accurate 3D volume rendered reconstruction of the internal and external morphology of a human extracted and endodontically treated tooth using a dataset of images acquired by magnetic resonance imaging. The external lingual and vestibular views of the tooth as well as the occlusal view of the pulp chamber, the access cavity, the distal canal opening on the pulp chamber floor, the coronal third of the root canals, the degree of root separation and the apical fusion of the two mesial roots, details of the apical region, root canal curvatures, furcal region and interradicular root grooves could be clearly bordered. Magnetic resonance imaging offers 3D image datasets with more information than the

  2. Sound lateralization ability of patients with bilateral microtia and atresia after bilateral reconstruction of auricles and external auditory canals and fitting of new canal-type hearing aids to replace a bone conduction hearing aid.

    Science.gov (United States)

    Kaga, Kimitaka; Asato, Hirotaka

    2017-04-01

    Each of eight patients with bilateral microtia and atresia underwent bilateral reconstruction of the auricles and external auditory canals and were fitted bilateral canal-type hearing aids in the operated ears to replace a bone conduction hearing aid. The ability to discriminate inter-aural intensity difference (IID) and even inter-aural time difference (ITD) was retained in all these patients. This study studied the post-operative sound lateralization ability of patients with bilateral microtia and atresia after total reconstruction of both auricles and external auditory canals, followed by fitting of bilateral canal-type hearing aids. Eight patients with bilateral microtia and atresia ranging in age from 13-43 years were recruited in this study. Each of them underwent bilateral reconstruction of the auricles and external auditory canals and were fitted canal-type hearing aids in both the operated ears to replace a bone conduction hearing aid. A sound lateralization test was conducted to determine IID and ITD discrimination ability thresholds. In all the patients, the IID discrimination ability thresholds of the patients were more than 3-fold those of the controls, the ITD discrimination ability threshold was more than 5-fold those of controls, and binaural hearing was retained.

  3. Evaluation of Control and Adjustment Structures of the Shibab Main Canal Using HEC-RAS

    Directory of Open Access Journals (Sweden)

    maryam mohammadi

    2017-02-01

    Full Text Available Introduction: Poor performance of irrigation and drainage networks causes to reduce the transfer and distribution throughputs and in result comes useless water and makes too much consumption in forming. A significant portion of water losses in irrigation and drainage networksis related to transmission and distribution. Therefor more consideration in thrirrigation network management, improve irrigation efficiency and also the exploitation of water resources, especially in the agricultural sector is necessary. Controlling and adjusting structures of water level in the direction of drainage and irrigation canals can influence on increasing of throughput and decrease the use of water. So, right choosing and recognition of the deficiencies of these structures helps carry up the throughput of the networks and prevents to waste water. It is hard to solve equations of water flow in canals and related institutions by using analytic methods. For this reason, this research was done with HEC-RAS hydraulical model in the main channelof irrigation and drainage network of Sistan plain. Materials and Methods: Sistan plain is located in southeastern of Iran with good potential for agricultural production because of the alluvial sediments from Hirmand River. 23820 ha of the Sistan plain is covered by 5 blocksof the Shibab irrigation and drainage network. While Sistan’sShibab irrigation network efficiency is low, HEC-RAS Hydraulics model in unsteady condition was performed to control and adjust this network’s main canal in approximately 19 Km length. In this research, the evaluation model in the canal was performed for more suitable intakingwater in the quadruple order 2 canals . So, the existing structure’s operation was analyzed on controlling structures in management and lack of management situations.This research was assessed during a 15-day impounding period using hydraulic model of HEC-RAS with the aim of performance and operation evaluation of

  4. Dynamics of fecal indicator bacteria, bacterial pathogen genes, and organic wastewater contaminants in the Little Calumet River: Portage Burns Waterway, Indiana

    Science.gov (United States)

    Haack, Sheridan K.; Duris, Joseph W.

    2013-01-01

    Little information exists on the co-occurrence of fecal indicator bacteria (FIB), bacterial pathogens, and organic wastewater-associated chemicals (OWCs) within Great Lakes tributaries. Fifteen watershed sites and one beach site adjacent to the Little Calumet River–Portage Burns Waterway (LCRPBW) on Lake Michigan were tested on four dates for pH, dissolved oxygen, specific conductance, chloride, color, ammonia- and nitrate-nitrogen, soluble phosphorus, sulfate, turbidity, and atrazine; for concentrations of FIB; and for genes indicating the presence of human-pathogenic enterococci (ENT) and of Shiga-toxin producing Escherichia coli (EC) from various animal sources. Nineteen samples were also tested for 60 OWCs. Half of the watershed samples met EC recreational water quality standards; none met ENT standards. Human-wastewater-associated OWC detections were correlated with human-influence indicators such as population/km2, chloride concentrations, and the presence of WWTP effluents, but EC and ENT concentrations were not. Bacterial pathogen genes indicated rural human and several potential animal sources. OWCs of human or ecosystem health concern (musk fragrances AHTN and HHCB, alkylphenols, carbamazepine) and 3 bacterial pathogen genes were detected at the mouth of the LCRPBW, but no such OWCs and only 1 pathogen gene were detected at the beach. The LCRPBW has significant potential to deliver FIB, potential bacterial pathogens, and OWCs of human or ecosystem health concern to the nearshore of Lake Michigan, under conditions enhancing nearshore transport of the river plume. Nearshore mixing of lake and river water, and the lack of relationship between OWCs and FIB or pathogen genes, pose numerous challenges for watershed and nearshore assessment and remediation.

  5. 75 FR 5769 - Inland Waterways Users Board; Request for Nominations

    Science.gov (United States)

    2010-02-04

    ... Department of the Army Inland Waterways Users Board; Request for Nominations AGENCY: Department of the Army, DOD. ACTION: Notice. SUMMARY: Section 302 of Public Law 99-662 established the Inland Waterways Users... Directorate, Attention: Inland Waterways Users Board Nominations Committee, Mr. Mark Pointon, 441 G Street, NW...

  6. 77 FR 1405 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA

    Science.gov (United States)

    2012-01-10

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA AGENCY... the SR 384 (Grand Lake) pontoon bridge across the Gulf Intracoastal Waterway, mile 231.4 West of... Lake Pontoon Bridge across the Gulf Intracoastal Waterway, mile 231.5 west of Harvey Lock (WHL), at...

  7. 77 FR 32393 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA

    Science.gov (United States)

    2012-06-01

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Gulf Intracoastal Waterway, LA AGENCY... Waterway (GIWW), mile 2.8 at New Orleans, Jefferson Parish, Louisiana. The deviation is necessary to allow... Waterway, mile 2.8 at New Orleans, Jefferson Parish, Louisiana. The bridge has a vertical clearance of 45...

  8. 77 FR 47826 - Inland Waterways Users Board; Request for Nominations

    Science.gov (United States)

    2012-08-10

    ... Department of the Army Inland Waterways Users Board; Request for Nominations AGENCY: Department of the Army, DOD. ACTION: Notice. SUMMARY: Section 302 of Public Law 99-662 established the Inland Waterways Users... Corps of Engineers, Attention: Inland Waterways Users Board Nominations Committee, Mr. Mark R. Pointon...

  9. 78 FR 23849 - Inland Waterways Navigation Regulation: Sacramento River, CA

    Science.gov (United States)

    2013-04-23

    ... SECURITY Coast Guard 33 CFR Part 162 RIN 1625-AB95 Inland Waterways Navigation Regulation: Sacramento River... entitled, ``Inland Waterways Navigation Regulation: Sacramento River, CA'' in the Federal Register (78 FR 4785). That rule announced our intent to update the inland waterways navigation regulations by removing...

  10. Comparison of the efficacy of Smear Clear with and without a canal brush in smear layer and debris removal from instrumented root canal using WaveOne versus ProTaper: a scanning electron microscopic study.

    Science.gov (United States)

    Kamel, Wael H; Kataia, Engy M

    2014-03-01

    The aim of this study was to compare by scanning electron microscopy the presence of smear layer and debris on root canal walls after preparation with the single-file system WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) versus the rotary ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) under 2 final irrigant regimens. Forty freshly extracted single-rooted human teeth were randomly divided into 4 groups (n = 10). The ProTaper and ProTaper and rotary CanalBrush (Coltène Whaledent GmbH+ Co KG, Langenau, Germany) groups were instrumented with the ProTaper system. Groups WaveOne and WaveOne and rotary CanalBrush were instrumented with the WaveOne system. The irrigant in all groups was 2 mL 5.25% sodium hypochlorite (NaOCl) solution, whereas the final irrigation after preparation in the ProTaper and WaveOne groups was 1 mL Smear Clear solution (Sybron Endo, Orange, CA) and then 5.25% NaOCl applied with a plastic syringe, and in the ProTaper and rotary CanalBrush and WaveOne and rotary CanalBrush groups, it was 1 mL Smear Clear solution and then 5.25% NaOCl (rotary CanalBrush agitation). Roots were processed for scanning electron microscopic examination for debris and smear layer scoring. Data were statistically analyzed. All groups showed more efficient smear layer and debris removal coronally than in the middle and apical regions, whereas the mean total debris score and the mean smear layer score in all groups were less in the WaveOne and rotary CanalBrush groups than the ProTaper and rotary CanalBrush and the WaveOne and ProTaper groups. Using the rotary CanalBrush in canals prepared with WaveOne produced the cleanest canal walls, and the WaveOne system gave superior results compared with the ProTaper system. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. Endodontic treatment of a C-shaped mandibular second premolar with four root canals and three apical foramina: a case report

    Directory of Open Access Journals (Sweden)

    Thikamphaa Bertrand

    2016-02-01

    Full Text Available This case report describes a unique C-shaped mandibular second premolar with four canals and three apical foramina and its endodontic management with the aid of cone-beam computer tomography (CBCT. C-shaped root canal morphology with four canals was identified under a dental operating microscope. A CBCT scan was taken to evaluate the aberrant root canal anatomy and devise a better instrumentation strategy based on the anatomy. All canals were instrumented to have a 0.05 taper using 1.0 mm step-back filing with appropriate apical sizes determined from the CBCT scan images and filled using a warm vertical compaction technique. A C-shaped mandibular second premolar with multiple canals is an anatomically rare case for clinicians, yet its endodontic treatment may require a careful instrumentation strategy due to the difficulty in disinfecting the canals in the thin root area without compromising the root structure.

  12. Prioritisation of farm scale remediation efforts for reducing losses of nutrients and faecal indicator organisms to waterways: a case study of New Zealand dairy farming.

    Science.gov (United States)

    Monaghan, R M; de Klein, C A M; Muirhead, R W

    2008-06-01

    The international competitiveness of the New Zealand (NZ) dairy industry is built on low cost clover-based systems and a favourable temperate climate that enables cows to graze pastures mostly all year round. Whilst this grazed pasture farming system is very efficient at producing milk, it has also been identified as a significant source of nutrients (N and P) and faecal bacteria which have contributed to water quality degradation in some rivers and lakes. In response to these concerns, a tool-box of mitigation measures that farmers can apply on farm to reduce environmental emissions has been developed. Here we report the potential reduction in nutrient losses and costs to farm businesses arising from the implementation of individual best management practices (BMPs) within this tool-box. Modelling analysis was carried out for a range of BMPs targeting pollutant source reduction on case-study dairy farms, located in four contrasting catchments. Due to the contrasting physical resources and management systems present in the four dairy catchments evaluated, the effectiveness and costs of BMPs varied. Farm managements that optimised soil Olsen P levels or used nitrification inhibitors were observed to result in win-win outcomes whereby nutrient losses were consistently reduced and farm profitability was increased in three of the four case study farming systems. Other BMPs generally reduced nutrient and faecal bacteria losses but at a small cost to the farm business. Our analysis indicates that there are a range of technological measures that can deliver substantial reductions in nutrient losses to waterways from dairy farms, whilst not increasing or even reducing other environmental impacts (e.g. greenhouse gas emissions and energy use). Their implementation will first require clearly defined environmental goals for the catchment/water body that is to be protected. Secondly, given that the major sources of water pollutants often differed between catchments, it is

  13. Influence of root canal instrumentation and obturation techniques on intra-operative pain during endodontic therapy

    OpenAIRE

    Martín González, Jenifer; Echevarría Pérez, Marta; Sánchez Domínguez, Benito; Tarilonte Delgado, María Luisa; Castellanos Cosano, Lizett; López Frias, Javier; Segura-Egea, Juan J.

    2012-01-01

    Objective: To analyse the influence of root canal instrumentation and obturation techniques on intra-operative pain experienced by patients during endodontic therapy. Method and Materials: A descriptive cross-sectional study was carried out in Ponferrada and Sevilla, Spain, including 80 patients (46 men and 34 women), with ages ranged from 10 to 74 years, randomly recruited. Patient gender and age, affected tooth, pulpal diagnosis, periapical status, previous NSAID or antibiotic (AB) treatmen...

  14. Association of endodontic signs and symptoms with root canal pathogens: A clinical comparative study

    OpenAIRE

    R V Vineet; Moksha Nayak; Subbannayya Kotigadde

    2016-01-01

    Objective: The purpose of this study was to evaluate the association of the common root canal pathogens namely; Streptococcus mitis and Enterococcus faecalis with specific endodontic signs and symptoms. Materials and Methods: Sixty subjects scheduled for endodontic treatment were divided into two groups comprising of 30 subjects with primary endodontic infections and 30 subjects with failed endodontic treatment. The endodontic signs and symptoms of the subjects were assessed using clinical an...

  15. Internal auditory canal meningocele-perilabyrinthine/translabyrinthine fistula: Case report and imaging.

    Science.gov (United States)

    Truesdale, Carl M; Peterson, Ryan B; Hudgins, Patricia A; Vivas, Esther X

    2016-08-01

    The case of a 17-year-old patient with progressive unilateral sensorineural hearing loss and temporal bone malformations concerning for internal auditory canal meningocele with translabyrinthine/perilabyrinthine cerebrospinal fluid fistula is presented with associated computed tomography and magnetic resonance imaging. As the second reported case of an unruptured internal auditory canal meningocele with translabyrinthine/perilabyrinthine fistula, the case presents several clinically relevant points for otologists, neurotologists, and neuroradiologists. Although rare, it is an additional entity to consider as a cause of unilateral sensorineural hearing loss and may pose a risk for developing meningitis and possible "gushing" of cerebrospinal fluid should surgical intervention be attempted. Laryngoscope, 126:1931-1934, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Surgical Procedures for External Auditory Canal Carcinoma and the Preservation of Postoperative Hearing

    Directory of Open Access Journals (Sweden)

    Hiroshi Hoshikawa

    2012-01-01

    Full Text Available Carcinoma of the external auditory canal (EAC is an unusual head and neck malignancy. The pathophysiology of these tumors is different from other skin lesions because of their anatomical and functional characteristics. Early-stage carcinoma of the EAC can be generally cured by surgical treatment, and reconstruction of the EAC with a tympanoplasty can help to retain hearing, thus improving the patients’ quality of life. In this study, we present two cases of early-stage carcinoma of the EAC treated by canal reconstruction using skin grafts after lateral temporal bone resection. A rolled-up skin graft with a temporal muscle flap was useful for keeping the form and maintaining the postoperative hearing. An adequate size of the skin graft and blood supply to the graft bed are important for achieving a successful operation.

  17. Evaluation of Chlorine Dioxide Irrigation Solution on the Microhardness and Surface Roughness of Root Canal Dentin.

    Science.gov (United States)

    Ballal, Nidambur Vasudev; Khandewal, Deepika; Karthikeyan, Saravana; Somayaji, Krishnaraj; Foschi, Federico

    2015-12-01

    The aim of this study was to evaluate the effect of chlorine dioxide and various other more common irrigation solutions on the microhardness and surface roughness of root canal dentin. Fifty human maxillary central incisors were sectioned longitudinally and treated for 1 minute with 5 ml of the following aqueous solutions (v/v%): Group 1: 13.8% chlorine dioxide, Group 2: 17% ethylene diamine tetraacetic acid (EDTA). Group 3: 7% maleic acid, Group 4: 2.5% sodium hypochlorite (5 ml/min), Group 5: Saline (control). Specimens were subjected to microhardness and surface roughness testing. Chlorine dioxide and sodium hypochlorite reduced the microhardness more than other test agents. The highest surface roughness was produced with maleic acid. Chlorine dioxide should be used cautiously during chemomechanical preparation of the root canal system in order to prevent untoward damage to the teeth.

  18. Detection of Enterococcus faecalis in Necrotic Teeth Root Canals by Culture and Polymerase Chain Reaction Methods

    OpenAIRE

    Cogulu, Dilsah; Uzel, Atac; Oncag, Ozant; Aksoy, Semiha C.; Eronat, Cemal

    2007-01-01

    Objectives The aim of this study was to investigate the presence of Enterococcus faecalis in endodontic infections in both deciduous and permanent teeth by culture and polymerase chain reaction (PCR) methods. Methods A total of 145 children aged 5?13 years old were involved in this study. The presence of E. faecalis in necrotic deciduous and permanent teeth root canals was studied using culture and polymerase chain reaction methods. Results Among 145 molar teeth, 57% (n=83) presented necrotic...

  19. Canal preparation and filling techniques do not influence the fracture resistance of extensively damaged teeth

    OpenAIRE

    Santini,Manuela Favarin; RIPPE,Marília Pivetta; Franciscatto,Gisele Jung; Rosa,Ricardo Abreu da; Valandro, Luiz Felipe; SÓ, Marcus Vinícius Reis; BIER,Carlos Alexandre Souza

    2014-01-01

    The purpose of this study was to assess the fracture resistance of extensively damaged teeth after two root canal preparation techniques (hand and rotary files) and after two filling techniques (active and passive compaction). Sixty-eight maxillary canines roots with an apical diameter equal to that of a #25 K-file were embedded in acrylic resin and the periodontal ligament was simulated by using a polyether impression material. The roots were randomly distributed into four groups (n=17): han...

  20. Does the Reciproc file remove root canal bacteria and endotoxins as effectively as multifile rotary systems?

    Science.gov (United States)

    Marinho, A C S; Martinho, F C; Gonçalves, L M; Rabang, H R C; Gomes, B P F A

    2015-06-01

    To evaluate the effectiveness of Reciproc for the removal of cultivable bacteria and endotoxins from root canals in comparison with multifile rotary systems. The root canals of forty human single-rooted mandibular pre-molars were contaminated with an Escherichia coli suspension for 21 days and randomly assigned to four groups according to the instrumentation system: GI - Reciproc (VDW); GII - Mtwo (VDW); GIII - ProTaper Universal (Dentsply Maillefer); and GIV -FKG Race(™) (FKG Dentaire) (n = 10 per group). Bacterial and endotoxin samples were taken with a sterile/apyrogenic paper point before (s1) and after instrumentation (s2). Culture techniques determined the colony-forming units (CFU) and the Limulus Amebocyte Lysate assay was used for endotoxin quantification. Results were submitted to paired t-test and anova. At s1, bacteria and endotoxins were recovered in 100% of the root canals investigated (40/40). After instrumentation, all systems were associated with a highly significant reduction of the bacterial load and endotoxin levels, respectively: GI - Reciproc (99.34% and 91.69%); GII - Mtwo (99.86% and 83.11%); GIII - ProTaper (99.93% and 78.56%) and GIV - FKG Race(™) (99.99% and 82.52%) (P endotoxin removal (P > 0.01). The reciprocating single file, Reciproc, was as effective as the multifile rotary systems for the removal of bacteria and endotoxins from root canals. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.